Cheung, Winston K; Myburgh, John; Seppelt, Ian M; Parr, Michael J; Blackwell, Nikki; Demonte, Shannon; Gandhi, Kalpesh; Hoyling, Larissa; Nair, Priya; Passer, Melissa; Reynolds, Claire; Saunders, Nicholas M; Saxena, Manoj K; Thanakrishnan, Govindasamy
2012-08-06
To determine the increase in intensive care unit (ICU) bed availability that would result from the use of the New South Wales and Ontario Health Plan for an Influenza Pandemic (OHPIP) triage protocols. Prospective evaluation study conducted in eight Australian, adult, general ICUs, between September 2009 and May 2010. All patients who were admitted to the ICU, excluding those who had elective surgery, were prospectively evaluated using the two triage protocols, simulating a pandemic situation. Both protocols were originally developed to determine which patients should be excluded from accessing ICU resources during an influenza pandemic. Increase in ICU bed availability. At admission, the increases in ICU bed availability using Tiers 1, 2 and 3 of the NSW triage protocol were 3.5%, 14.7% and 22.7%, respectively, and 52.8% using the OHPIP triage protocol (P < 0.001). Re-evaluation of patients at 12 hours after admission using Tiers 1, 2 and 3 of the NSW triage protocol incrementally increased ICU bed availability by 19.2%, 16.1% and 14.1%, respectively (P < 0.001). The maximal cumulative increases in ICU bed availability using Tiers 1, 2 and 3 of the NSW triage protocol were 23.7%, 31.6% and 37.5%, respectively, at 72 hours (P < 0.001), and 65.0% using the OHPIP triage protocol, at 120 hours (P < 0.001). Both triage protocols resulted in increases in ICU bed availability, but the OHPIP protocol provided the greatest increase overall. With the NSW triage protocol, ICU bed availability increased as the protocol was escalated.
van Rein, Eveline A J; Houwert, R Marijn; Gunning, Amy C; Lichtveld, Rob A; Leenen, Luke P H; van Heijl, Mark
2017-08-01
Prehospital trauma triage ensures proper transport of patients at risk of severe injury to hospitals with an appropriate corresponding level of trauma care. Incorrect triage results in undertriage and overtriage. The American College of Surgeons Committee on Trauma recommends an undertriage rate below 5% and an overtriage rate below 50% for prehospital trauma triage protocols. To find the most accurate prehospital trauma triage protocol, a clear overview of all currently available protocols and corresponding outcomes is necessary. The aim of this systematic review was to evaluate the current literature on all available prehospital trauma triage protocols and determine accuracy of protocol-based triage quality in terms of sensitivity and specificity. A search of Pubmed, Embase, and Cochrane Library databases was performed to identify all studies describing prehospital trauma triage protocols before November 2016. The search terms included "trauma," "trauma center," or "trauma system" combined with "triage," "undertriage," or "overtriage." All studies describing protocol-based triage quality were reviewed. To assess the quality of these type of studies, a new critical appraisal tool was developed. In this review, 21 articles were included with numbers of patients ranging from 130 to over 1 million. Significant predictors for severe injury were: vital signs, suspicion of certain anatomic injuries, mechanism of injury, and age. Sensitivity ranged from 10% to 100%; specificity from 9% to 100%. Nearly all protocols had a low sensitivity, thereby failing to identify severely injured patients. Additionally, the critical appraisal showed poor quality of the majority of included studies. This systematic review shows that nearly all protocols are incapable of identifying severely injured patients. Future studies of high methodological quality should be performed to improve prehospital trauma triage protocols. Systematic review, level III.
Staub, Gabrielle Marmier; von Overbeck, Jan; Blozik, Eva
2013-09-30
Quality assessment and continuous quality feedback to the staff is crucial for safety and efficiency of teleconsultation and triage. This study evaluates whether it is feasible to use an already existing telephone triage protocol to assess the appropriateness of point-of-care and time-to-treat recommendations after teleconsultations. Based on electronic patient records, we retrospectively compared the point-of-care and time-to-treat recommendations of the paediatric telephone triage protocol with the actual recommendations of trained physicians for children with abdominal pain, following a teleconsultation. In 59 of 96 cases (61%) these recommendations were congruent with the paediatric telephone protocol. Discrepancies were either of organizational nature, due to factors such as local referral policies or gatekeeping insurance models, or of medical origin, such as milder than usual symptoms or clear diagnosis of a minor ailment. A paediatric telephone triage protocol may be applicable in healthcare systems other than the one in which it has been developed, if triage rules are adapted to match the organisational aspects of the local healthcare system.
Benedict, Leo Andrew; Paulus, Jessica K; Rideout, Leslie; Chwals, Walter J
2014-01-01
To assess whether pediatric trauma patients initially evaluated at referring institutions met Massachusetts statewide trauma field triage criteria for stabilization and immediate transfer to a Pediatric Trauma Center (PTC) without pre-transfer CT imaging. A 3-year retrospective cohort study was completed at our level 1 PTC. Patients with CT imaging at referring institutions were classified according to a triage scheme based on Massachusetts statewide trauma field triage criteria. Demographic data and injury profile characteristics were abstracted from patient medical records and our pediatric trauma registry. A total of 262 patients with 413 CT scans were reviewed from 2008 to 2011. 172 patients scanned (66%, 95% CI: 60%, 71%) met criteria for immediate transfer to a pediatric trauma center. Notably, 110 scans (27% of the total performed at referring institutions) were duplicated within four hours upon arrival to our PTC. GCS score <14 (45%) was the most common requirement for transfer, and CT scan of the head was the most frequent scan obtained (53%). The majority of pediatric trauma patients were subjected to CT scans at referring institutions despite meeting Massachusetts trauma triage guidelines that call for stabilization and immediate transfer to a pediatric trauma center without any CT imaging. © 2014.
Emergency department imaging: are weather and calendar factors associated with imaging volume?
Burns, K; Chernyak, V; Scheinfeld, M H
2016-12-01
To identify weather and calendar factors that would enable prediction of daily emergency department (ED) imaging volume to aid appropriate scheduling of imaging resources for efficient ED function. Daily ED triage and imaging volumes for radiography, computed tomography (CT), and ultrasound were obtained from hospital databases for the period between January 2011 and December 2013 at a large tertiary urban hospital with a Level II trauma centre. These data were tabulated alongside daily weather conditions (temperature, wind and precipitation), day of week, season, and holidays. Multivariate analysis was performed. Pearson correlations were used to measure the association between number of imaging studies performed and ED triage volume. For every additional 50 triaged patients, the odds of having high (imaging volume ≥90th percentile) radiography, CT, and ultrasound volume increased by 4.3 times (p<0.001), 1.5 times (p=0.02), and 1.4 times (p=0.02), respectively. Tuesday was an independent predictor of high radiography volume (odds ratio=2.8) and Monday was an independent predictor of high CT volume (odds ratio=3.0). Weekday status was an independent factor increasing the odds of a high US volume compared to Saturday (odds ratios ranging from 5.6-9.8). Weather factors and other calendar variables were not independent predictors of high imaging volume. Using Pearson correlations, ED triage volume correlated with number of radiographs, CT, and ultrasound examinations with r=0.73, 0.37, and 0.41, respectively (p<0.0001). As ED triage volume was found to be the only factor associated with imaging volume for all techniques, analysis of predictors of ED triage volumes at a particular healthcare facility would be useful to determine imaging needs. Although calendar and weather factors were found to be minor or non-significant independent predictors of ED imaging utilisation, these may be important in influencing the actual number of ED triages. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Partiality, impartiality and the ethics of triage.
Okorie, Ndukaku
2018-06-22
In this paper, I discuss the question of partiality and impartiality in the application of triage. Triage is a process in medical research which recommends that patients should be sorted for treatment according to the degree or severity of their injury. In employing the triage protocol, however, the question of partiality arises because socially vulnerable groups will be neglected since there is the likelihood that the social determinants of a patient's health may diminish her chance of survival. As a process that is based on the severity of a patient's injury, triage will be unfair, and hence negatively partial, to socially vulnerable people. Thus, I aim in this paper to show that the triage protocol fails as an impartial evaluative process because its only aim is to maximize survivability. I contend that: (i) triage would lead to the neglect of the social condition of patients or victims, and (ii) it will only serve the utilitarian purpose of maximization of outcomes which may not be justified in some cases. © 2018 John Wiley & Sons Ltd.
Sacino, Amanda N; Shuster, Jonathan J; Nowicki, Kamil; Carek, Peter J; Wegman, Martin P; Listhaus, Alyson; Gibney, Joseph M; Chang, Ku-Lang
2016-02-01
As the number of patients with access to care increases, outpatient clinics will need to implement innovative strategies to maintain or enhance clinic efficiency. One viable alternative involves reverse triage. A reverse triage protocol was implemented during a student-run free clinic. Each patient's chief complaint(s) were obtained at the beginning of the clinic session and ranked by increasing complexity. "Complexity" was defined as the subjective amount of time required to provide a full, thorough evaluation of a patient. Less complex cases were prioritized first since they could be expedited through clinic processing and allow for more time and resources to be dedicated to complex cases. Descriptive statistics were used to characterize and summarize the data obtained. Categorical variables were analyzed using chi-square. A time series analysis of the outcome versus centered time in weeks was also conducted. The average number of patients seen per clinic session increased by 35% (9.5 versus 12.8) from pre-implementation of the reverse triage protocol to 6 months after the implementation of the protocol. The implementation of a reverse triage in an outpatient setting significantly increased clinic efficiency as noted by a significant increase in the number of patients seen during a clinic session.
Beck-Razi, Nira; Fischer, Doron; Michaelson, Moshe; Engel, Ahuva; Gaitini, Diana
2007-09-01
The purpose of this study was to evaluate the role of focused assessment with sonography for trauma (FAST) as a triage tool in multiple-casualty incidents (MCIs) for a single international conflict. The charts of 849 casualties that arrived at our level 1 trauma referral center were reviewed. Casualties were initially triaged according to the Injury Severity Score at the emergency department gate. Two-hundred eighty-one physically injured patients, 215 soldiers (76.5%) and 66 civilians (23.5%), were admitted. Focused assessment with sonography for trauma was performed in 102 casualties suspected to have an abdominal injury. Sixty-eight underwent computed tomography (CT); 12 underwent laparotomy; and 28 were kept under clinical observation alone. We compared FAST results against CT, laparotomy, and clinical observation records. Focused assessment with sonography for trauma results were positive in 17 casualties and negative in 85. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FAST were 75%, 97.6%, 88.2%, 94.1%, and 93.1%, respectively. A strong correlation between FAST and CT results, laparotomy, and clinical observation was obtained (P < .05). In a setting of a war conflict-related MCI, FAST enabled immediate triage of casualties to laparotomy, CT, or clinical observation. Because of its moderate sensitivity, a negative FAST result with strong clinical suspicion demands further evaluation, especially in an MCI.
Factors that affect the flow of patients through triage.
Lyons, Melinda; Brown, Ruth; Wears, Robert
2007-02-01
To use observational methods to objectively evaluate the organisation of triage and what issues may affect the effectiveness of the process. A two-phase study comprising observation of 16 h of triage in a London hospital emergency department and interviews with the triage staff to build a qualitative task analysis and study protocol for phase 2; observation and timing in triage for 1870 min including 257 patients and for 16 different members of the triage staff. No significant difference was found between grades of staff for the average triage time or the fraction of time absent from triage. In all, 67% of the time spent absent from triage was due to escorting patients into the department. The average time a patient waited in the reception before triage was 13 min 34 s; the average length of time to triage for a patient was 4 min 17 s. A significant increase in triage time was found when patients were triaged to a specialty, expected by a specialty, or were actively "seen and treated" in triage. Protocols to prioritise patients with potentially serious conditions to the front of the queue had a significantly positive effect on their waiting time. Supplementary tasks and distractions had varying effects on the timely assessment and triage of patients. The human factors method is applicable to the triage process and can identify key factors that affect the throughput at triage. Referring a patient to a specialty at triage affects significantly the triage workload; hence, alternative methods or management should be suggested. The decision to offer active treatment at triage increases the time taken, and should be based on clinical criteria and the workload determined by staffing levels. The proportion of time absent from triage could be markedly improved by support from porters or other non-qualified staff, as well as by proceduralised handovers from triage to the main clinical area. Triage productivity could be improved by all staff by becoming aware of the effect of the number of interruptions on the throughput of patients.
Srinivasan, Abhay; Servaes, Sabah; Peña, Andrès; Darge, Kassa
2015-02-01
To improve diagnosis of pediatric appendicitis, many institutions have implemented a staged imaging protocol utilizing ultrasonography (US) first and then computed tomography (CT). A substantial number of children with suspected appendicitis undergo CT after US, and the efficient and accurate diagnosis of pediatric appendicitis continues to be challenging. The objective of the study is to characterize the utility of CT following US for diagnosis of pediatric appendicitis, in conjunction with a clinical appendicitis score (AS). Imaging studies of children with suspected appendicitis who underwent CT after US in an imaging protocol were retrospectively reviewed by three radiologists in consensus. Chart review derived the AS (range 0-10) and obtained the patient diagnosis and disposition, and an AS was applied to each patient. Clinical and radiologic data were analyzed to assess the yield of CT after US. Studies of 211 children (mean age 11.3 years) were included. The positive threshold for AS was determined to be 6 out of 10. When AS and US were concordant (N = 140), the sensitivity and specificity of US were similar to CT. When AS and US were discordant (N = 71) and also when AS ≥ 6 (N = 84), subsequent CT showed superior sensitivity and specificity to US alone. In the subset where US showed neither the appendix nor inflammatory change in the right lower quadrant (126/211, 60 % of scans), when AS < 6 (N = 83), the negative predictive value (NPV) of US was 0.98. However, when AS ≥ 6 (N = 43), NPV of US was 0.58, and the positive predictive value of subsequent CT was 1. There was a significant decrease in depiction of the appendix on US with patient weight-to-age ratio of >6 (kg/year, P < 0.001) and after-hours (1700 -0730 hours) performance of US (P < 0.001). Results suggest that the appendicitis score has utility in guiding an imaging protocol and support the contention that non-visualization of the appendix on US is not intrinsically non-diagnostic. There was little benefit to additional CT when AS < 6 and US did not show the appendix or evidence of inflammation; this would have avoided CT in 140/211 (66 %) patients. CT demonstrated benefit when AS ≥ 6, suggesting that cases with AS ≥ 6 and features that limit depiction of the appendix on US may be triaged to CT.
Janjua, M Burhan; Hoffman, Caitlin E; Souweidane, Mark M
2017-11-01
The management of hydrocephalus can be challenging even in expert hands. Due to acute presentation, recurrence, accompanying complications, the need for urgent diagnosis; a robust management plan is an absolute necessity. We devised a novel time efficient surveillance strategy during emergency, and clinic follow up settings which has never been described in the literature. We searched all articles embracing management/surveillance protocol on pediatric hydrocephalus utilizing the terms "hydrocephalus follow up" or "surveillance protocol after hydrocephalus treatment". The authors present their own strategy based on vast experience in the hydrocephalus management at a single institution. The need for the diagnostic laboratory testing, age and presentation based radiological imaging, significance of neuro-opthalmological exam, and when to consider the emergent exploration have been discussed in detail. Moreover, a definitive triaging strategy has been described with the help of flow chart diagrams for clinicians, and the neurosurgeons in practice. The triage starts from detail history, physical exam, necessary labs, radiological imaging depending on the presentation, and the age of the child. A quick head CT scan helps after shunt surgery while, a FAST sequence MRI scan (fsMRI) is important in post ETV patients. The need for neuro-opthalmological exam, and the shunt series stays vital in asymptomatic patients during regular follow up. Copyright © 2017 Elsevier Ltd. All rights reserved.
Development and evaluation of an influenza pandemic intensive care unit triage protocol.
Cheung, Winston; Myburgh, John; Seppelt, Ian M; Parr, Michael J; Blackwell, Nikki; Demonte, Shannon; Gandhi, Kalpesh; Hoyling, Larissa; Nair, Priya; Passer, Melissa; Reynolds, Claire; Saunders, Nicholas M; Saxena, Manoj K; Thanakrishnan, Govindasamy
2012-09-01
To develop an influenza pandemic ICU triage (iPIT) protocol that excludes patients with the highest and lowest predicted mortality rates, and to determine the increase in ICU bed availability that would result. Post-hoc analysis of a study evaluating two triage protocols, designed to determine which patients should be excluded from access to ICU resources during an influenza pandemic. ICU mortality rates were determined for the individual triage criteria in the protocols and included criteria based on the Sequential Organ Failure Assessment (SOFA) score. Criteria resulting in mortality rates outside the 25th and 75th percentiles were used as exclusion criteria in a new iPIT-1 protocol. The SOFA threshold component was modified further and reported as iPIT-2 and iPIT-3. Increase in ICU bed availability. The 25th and 75th percentiles for ICU mortality were 8.3% and 35.2%, respectively. Applying the iPIT-1 protocol resulted in an increase in ICU bed availability at admission of 71.7% ± 0.6%. Decreasing the lower SOFA score exclusion criteria to ≤6 (iPIT-2) and ≤4 (iPIT-3) resulted in an increase in ICU bed availability at admission of 66.9% ± 0.6% and 59.4 ± 0.7%, respectively (P < 0.001). The iPIT protocol excludes patients with the lowest and highest ICU mortality, and provides increases in ICU bed availability. Adjusting the lower SOFA score exclusion limit provides a method of escalation or de- escalation to cope with demand.
Welling, Lieke; Perez, Roberto S G M; van Harten, Sabine M; Patka, Peter; Mackie, Dave P; Kreis, Robert W; Bierens, Joost J L M
2005-12-01
At this moment, in the Netherlands, rescue workers are not given any specific standardized training in disaster response or disaster management. After the café fire in Volendam, the Netherlands, on New Year's Eve 2000, around 200 rescue workers were deployed on-site. The aim of this study is to investigate the rescue workers' experiences with regard to their level of preparation for the emergency response. In 2002, 30 members of the medical and paramedical personnel were requested to participate in a structured interview, focused on education, task perception, triage and registration. Twenty-seven participated. Twenty-two rescue workers received previous training in emergency medicine. During the alarm phase, 11 rescue workers had a clear perception of their tasks. Twenty-four were involved in triage and injury assessment. Three rescue workers used a protocol for triage and 15 for injury assessment. Twenty-five rescue workers gave on-scene treatment and 15 used a protocol. Eight registered their findings. Preparation for the emergency response lacked standardized procedures. The use of triage protocols was extremely poor, as was documentation of actions. Slightly more than half of the personnel followed treatment protocols. It is advisable that all rescue workers become familiar with the basic uniform principles and protocols regarding disaster management. A dedicated and standardized national disaster management course is needed for all rescue workers.
Trauma Quality Improvement: Reducing Triage Errors by Automating the Level Assignment Process.
Stonko, David P; O Neill, Dillon C; Dennis, Bradley M; Smith, Melissa; Gray, Jeffrey; Guillamondegui, Oscar D
2018-04-12
Trauma patients are triaged by the severity of their injury or need for intervention while en route to the trauma center according to trauma activation protocols that are institution specific. Significant research has been aimed at improving these protocols in order to optimize patient outcomes while striving for efficiency in care. However, it is known that patients are often undertriaged or overtriaged because protocol adherence remains imperfect. The goal of this quality improvement (QI) project was to improve this adherence, and thereby reduce the triage error. It was conducted as part of the formal undergraduate medical education curriculum at this institution. A QI team was assembled and baseline data were collected, then 2 Plan-Do-Study-Act (PDSA) cycles were implemented sequentially. During the first cycle, a novel web tool was developed and implemented in order to automate the level assignment process (it takes EMS-provided data and automatically determines the level); the tool was based on the existing trauma activation protocol. The second PDSA cycle focused on improving triage accuracy in isolated, less than 10% total body surface area burns, which we identified to be a point of common error. Traumas were reviewed and tabulated at the end of each PDSA cycle, and triage accuracy was followed with a run chart. This study was performed at Vanderbilt University Medical Center and Medical School, which has a large level 1 trauma center covering over 75,000 square miles, and which sees urban, suburban, and rural trauma. The baseline assessment period and each PDSA cycle lasted 2 weeks. During this time, all activated, adult, direct traumas were reviewed. There were 180 patients during the baseline period, 189 after the first test of change, and 150 after the second test of change. All were included in analysis. Of 180 patients, 30 were inappropriately triaged during baseline analysis (3 undertriaged and 27 overtriaged) versus 16 of 189 (3 undertriaged and 13 overtriaged) following implementation of the web tool (p = 0.017 for combined errors). Overtriage dropped further from baseline to 10/150 after the second test of change (p = 0.005). The total number of triaged patients dropped from 92.3/week to 75.5/week after the second test of change. There was no statistically significant change in the undertriage rate. The combination of web tool implementation and protocol refinement decreased the combined triage error rate by over 50% (from 16.7%-7.9%). We developed and tested a web tool that improved triage accuracy, and provided a sustainable method to enact future quality improvement. This web tool and QI framework would be easily expandable to other hospitals. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Mass-casualty triage: time for an evidence-based approach.
Jenkins, Jennifer Lee; McCarthy, Melissa L; Sauer, Lauren M; Green, Gary B; Stuart, Stephanie; Thomas, Tamara L; Hsu, Edbert B
2008-01-01
Mass-casualty triage has developed from a wartime necessity to a civilian tool to ensure that constrained medical resources are directed at achieving the greatest good for the most number of people. Several primary and secondary triage tools have been developed, including Simple Treatment and Rapid Transport (START), JumpSTART, Care Flight Triage, Triage Sieve, Sacco Triage Method, Secondary Assessment of Victim Endpoint (SAVE), and Pediatric Triage Tape. Evidence to support the use of one triage algorithm over another is limited, and the development of effective triage protocols is an important research priority. The most widely recognized mass-casualty triage algorithms in use today are not evidence-based, and no studies directly address these issues in the mass-casualty setting. Furthermore, no studies have evaluated existing mass-casualty triage algorithms regarding ease of use, reliability, and validity when biological, chemical, or radiological agents are introduced. Currently, the lack of a standardized mass-casualty triage system that is well validated, reliable, and uniformly accepted, remains an important gap. Future research directed at triage is recognized as a necessity, and the development of a practical, universal, triage algorithm that incorporates requirements for decontamination or special precautions for infectious agents would facilitate a more organized mass-casualty medical response.
Christian, Michael D; Joynt, Gavin M; Hick, John L; Colvin, John; Danis, Marion; Sprung, Charles L
2010-04-01
To provide recommendations and standard operating procedures for intensive care unit (ICU) and hospital preparations for an influenza pandemic or mass disaster with a specific focus on critical care triage. Based on a literature review and expert opinion, a Delphi process was used to define the essential topics including critical care triage. Key recommendations include: (1) establish an Incident Management System with Emergency Executive Control Groups at facility, local, regional/state or national levels to exercise authority and direction over resources; (2) developing fair and equitable policies may require restricting ICU services to patients most likely to benefit; (3) usual treatments and standards of practice may be impossible to deliver; (4) ICU care and treatments may have to be withheld from patients likely to die even with ICU care and withdrawn after a trial in patients who do not improve or deteriorate; (5) triage criteria should be objective, ethical, transparent, applied equitably and be publically disclosed; (6) trigger triage protocols for pandemic influenza only when critical care resources across a broad geographic area are or will be overwhelmed despite all reasonable efforts to extend resources or obtain additional resources; (7) triage of patients for ICU should be based on those who are likely to benefit most or a 'first come, first served' basis; (8) a triage officer should apply inclusion and exclusion criteria to determine patient qualification for ICU admission. Judicious planning and adoption of protocols for critical care triage are necessary to optimize outcomes during a pandemic.
Philips, H; Van Bergen, J; Huibers, L; Colliers, A; Bartholomeeusen, S; Coenen, S; Remmen, R
2015-10-01
In some European countries telephone triage (TT) during out-of-hours primary care showed to be safe and effective. Other countries, such as Belgium, may not have trained auxiliary personnel while their national health services want to establish TT. To compare urgency levels assessed by secretaries and general practitioners in one general practice cooperative in Belgium. Percentage of correct-, under-, and over-triage were calculated in total and per reason for encounter. Inter-rater agreement was investigated. The secretaries correctly triaged (same urgency level) 77% of the telephone calls, under-triaged 10% and over-triaged 13%.'Shortness of breath', 'skin cuts', 'chest pain', 'feeling unwell' and 'syncope' were often under-triaged. Before introducing TT, auxiliary staff should be trained and protocols should be used.
Accuracy of Pediatric Trauma Field Triage: A Systematic Review.
van der Sluijs, Rogier; van Rein, Eveline A J; Wijnand, Joep G J; Leenen, Luke P H; van Heijl, Mark
2018-05-16
Field triage of pediatric patients with trauma is critical for transporting the right patient to the right hospital. Mortality and lifelong disabilities are potentially attributable to erroneously transporting a patient in need of specialized care to a lower-level trauma center. To quantify the accuracy of field triage and associated diagnostic protocols used to identify children in need of specialized trauma care. MEDLINE, Embase, PsycINFO, and Cochrane Register of Controlled Trials were searched from database inception to November 6, 2017, for studies describing the accuracy of diagnostic tests to identify children in need of specialized trauma care in a prehospital setting. Identified articles with a study population including patients not transported by emergency medical services were excluded. Quality assessment was performed using a modified version of the Quality Assessment of Diagnostic Accuracy Studies-2. After deduplication, 1430 relevant articles were assessed, a full-text review of 38 articles was conducted, and 5 of those articles were included. All studies were observational, published between 1996 and 2017, and conducted in the United States, and data collection was prospective in 1 study. Three different protocols were studied that analyzed a combined total of 1222 children in need of specialized trauma care. One protocol was specifically developed for a pediatric out-of-hospital cohort. The percentage of pediatric patients requiring specialized trauma care in each study varied between 2.6% (110 of 4197) and 54.7% (58 of 106). The sensitivity of the prehospital triage tools ranged from 49.1% to 87.3%, and the specificity ranged from 41.7% to 84.8%. No prehospital triage protocol alone complied with the international standard of 95% or greater sensitivity. Undertriage and overtriage rates, representative of the quality of the full diagnostic strategy to transport a patient to the right hospital, were not reported for inclusive trauma systems or emergency medical services regions. It is crucial to transport the right patient to the right hospital. Yet the quality of the full diagnostic strategy to determine the optimal receiving hospital is unknown. None of the investigated field triage protocols complied with current sensitivity targets. Improved efforts are needed to develop accurate child-specific tools to prevent undertriage and its potential life-threatening consequences.
1997-06-01
situations. The USAMH population includes 32,793 family members, many who are young spouses with small children . A recent study of USAMH emergency room...software is based on the work of Shiela Q. Wheeler, considered a pioneer in triage nursing and author of Telephone Triage: Theory . Practice and Protocol...personnel at USAMH established personnel levels at the Table of Distribution and Allowances ( TDA ) level with no overhires authorized. The working group
Developing research criteria to define medical necessity in emergency medical services.
Cone, David C; Schmidt, Terri A; Mann, N Clay; Brown, Lawrence
2004-01-01
"The Neely Conference: Developing Research Criteria to Define Medical Necessity in EMS" convened emergency medical services (EMS) physicians, researchers, administrators, providers, and federal agency representatives to begin the development of a set of uniform triage criteria and outcome measures that could be used to study and evaluate medical necessity among EMS patients. These standardized criteria might be used in research studies examining EMS dispatch and response (e.g., dispatch triage protocols, alternative response configurations), and EMS treatment and transport (e.g., field triage protocols, alternative care destinations). The conference process included review and analysis of the literature, expert judgment, and consensus building. There was general agreement on the following: 1. Any dispatch triage or field triage system that is developed must be designed to offer patients alternatives to EMS, not to refuse care to patients. 2. It is theoretically possible to develop a set of clinical criteria for need. Some groups of patients will clearly need a traditional EMS response and other groups will not, but this has yet to be defined. 3. In addition to clinical criteria, certain social and other nonclinical criteria such as pain or potential abuse may be used to justify a response. 4. Communication barriers, patient age, special needs, and other conditions complicate patient assessment but should not exclude patients from consideration for alternate triage or transport. 5. These research questions are important, and standard sets of outcome measures are needed so that different studies and innovative programs can be compared.
Hanley, Daniel; Prichep, Leslie S; Bazarian, Jeffrey; Huff, J Stephen; Naunheim, Rosanne; Garrett, John; Jones, Elizabeth B; Wright, David W; O'Neill, John; Badjatia, Neeraj; Gandhi, Dheeraj; Curley, Kenneth C; Chiacchierini, Richard; O'Neil, Brian; Hack, Dallas C
2017-05-01
A brain electrical activity biomarker for identifying traumatic brain injury (TBI) in emergency department (ED) patients presenting with high Glasgow Coma Scale (GCS) after sustaining a head injury has shown promise for objective, rapid triage. The main objective of this study was to prospectively evaluate the efficacy of an automated classification algorithm to determine the likelihood of being computed tomography (CT) positive, in high-functioning TBI patients in the acute state. Adult patients admitted to the ED for evaluation within 72 hours of sustaining a closed head injury with GCS 12 to 15 were candidates for study. A total of 720 patients (18-85 years) meeting inclusion/exclusion criteria were enrolled in this observational, prospective validation trial, at 11 U.S. EDs. GCS was 15 in 97%, with the first and third quartiles being 15 (interquartile range = 0) in the study population at the time of the evaluation. Standard clinical evaluations were conducted and 5 to 10 minutes of electroencephalogram (EEG) was acquired from frontal and frontal-temporal scalp locations. Using an a priori derived EEG-based classification algorithm developed on an independent population and applied to this validation population prospectively, the likelihood of each subject being CT+ was determined, and performance metrics were computed relative to adjudicated CT findings. Sensitivity of the binary classifier (likely CT+ or CT-) was 92.3% (95% confidence interval [CI] = 87.8%-95.5%) for detection of any intracranial injury visible on CT (CT+), with specificity of 51.6% (95% CI = 48.1%-55.1%) and negative predictive value (NPV) of 96.0% (95% CI = 93.2%-97.9%). Using ternary classification (likely CT+, equivocal, likely CT-) demonstrated enhanced sensitivity to traumatic hematomas (≥1 mL of blood), 98.6% (95% CI = 92.6%-100.0%), and NPV of 98.2% (95% CI = 95.5%-99.5%). Using an EEG-based biomarker high accuracy of predicting the likelihood of being CT+ was obtained, with high NPV and sensitivity to any traumatic bleeding and to hematomas. Specificity was significantly higher than standard CT decision rules. The short time to acquire results and the ease of use in the ED environment suggests that EEG-based classifier algorithms have potential to impact triage and clinical management of head-injured patients. © 2017 by the Society for Academic Emergency Medicine.
Fessler, Stephanie J; Simon, Harold K; Yancey, Arthur H; Colman, Michael; Hirsh, Daniel A
2014-03-01
The use of Emergency Medical Services (EMS) for low-acuity pediatric problems is well documented. Attempts have been made to curb potentially unnecessary transports, including using EMS dispatch protocols, shown to predict acuity and needs of adults. However, there are limited data about this in children. The primary objective of this study is to determine the pediatric emergency department (PED) resource utilization (surrogate of acuity level) for pediatric patients categorized as "low-acuity" by initial EMS protocols. Records of all pediatric patients classified as "low acuity" and transported to a PED in winter and summer of 2010 were reviewed. Details of the PED visit were recorded. Patients were categorized and compared based on chief complaint group. Resource utilization was defined as requiring any prescription medications, labs, procedures, consults, admission or transfer. "Under-triage" was defined as a "low-acuity" EMS transport subsequently requiring emergent interventions. Of the 876 eligible cases, 801 were included; 392/801 had no resource utilization while 409 of 801 had resource utilization. Most (737/801) were discharged to home; however, 64/801 were admitted, including 1 of 801 requiring emergent intervention (under-triage rate 0.12%). Gastroenterology and trauma groups had a significant increase in resource utilization, while infectious disease and ear-nose-throat groups had decreased resource utilization. While this EMS system did not well predict overall resource utilization, it safely identified most low-acuity patients, with a low under-triage rate. This study identifies subgroups of patients that could be managed without emergent transport and can be used to further refine current protocols or establish secondary triage systems. © 2013.
World's First 24/7 Mobile Stroke Unit: Initial 6-Month Experience at Mercy Health in Toledo, Ohio.
Lin, Eugene; Calderon, Victoria; Goins-Whitmore, Julie; Bansal, Vibhav; Zaidat, Osama
2018-01-01
As the fourth mobile stroke unit (MSU) in the nation, and the first 24/7 unit worldwide, we review our initial experience with the Mercy Health MSU and institutional protocols implemented to facilitate rapid treatment of acute stroke patients and field triage for patients suffering other time-sensitive, acute neurologic emergencies in Lucas County, Ohio, and the greater Toledo metropolitan area. Data was prospectively collected for all patients transported and treated by the MSU during the first 6 months of service. Data was abstracted from documentation of on-scene emergency medical services (EMS) personnel, critical care nurses, and onboard physicians, who participated through telemedicine. The MSU was dispatched 248 times and transported 105 patients after on-scene examination with imaging. Intravenous (IV) tissue plasminogen activator (tPA) was administered to 10 patients; 8 patients underwent successful endovascular therapy after a large vessel occlusion was identified using CT performed within the MSU without post treatment symptomatic hemorrhage. Moreover, 14 patients were treated with IV anti-epileptics for status epilepticus, and 19 patients received IV anti-hypertensive agents for malignant hypertension. MSU alarm to on-scene times and treatment times were 34.7 min (25-49) and 50.6 min (44.4-56.8), respectively. The world's first 24/7 MSU has been successfully implemented with IV-tPA administration rates and times comparable to other MSUs nation-wide, while demonstrating rapid triage and treatment in the field for neurologic emergencies, including status epilepticus. With the rising number of MSUs worldwide, further data will drive standardized protocols that can be adopted nationwide by EMS.
Point-of-Care Ultrasound for Pulmonary Concerns in Remote Spaceflight Triage Environments.
Johansen, Benjamin D; Blue, Rebecca S; Castleberry, Tarah L; Antonsen, Erik L; Vanderploeg, James M
2018-02-01
With the development of the commercial space industry, growing numbers of spaceflight participants will engage in activities with a risk for pulmonary injuries, including pneumothorax, ebullism, and decompression sickness, as well as other concomitant trauma. Medical triage capabilities for mishaps involving pulmonary conditions have not been systematically reviewed. Recent studies have advocated the use of point-of-care ultrasound to screen for lung injury or illness. The operational utility of portable ultrasound systems in disaster relief and other austere settings may be relevant to commercial spaceflight. A systematic review of published literature was conducted concerning the use of point-of-care pulmonary ultrasound techniques in austere environments, including suggested examination protocols for triage and diagnosis. Recent studies support the utility of pulmonary ultrasound examinations when performed by skilled operators, and comparability of the results to computed tomography and chest radiography for certain conditions, with important implications for trauma management in austere environments. Pulmonary injury and illness are among the potential health risks facing spaceflight participants. Implementation of point-of-care ultrasound protocols could aid in the rapid diagnosis, triage, and treatment of such conditions. Though operator-dependent, ultrasound, with proper training, experience, and equipment, could be a valuable tool in the hands of a first responder supporting remote spaceflight operations.Johansen BD, Blue RS, Castleberry TL, Antonsen EL, Vanderploeg JM. Point-of-care ultrasound for pulmonary concerns in remote spaceflight triage environments. Aerosp Med Hum Perform. 2018; 89(2):122-129.
Triage and optimization: A new paradigm in the treatment of massive pulmonary embolism.
Pasrija, Chetan; Shah, Aakash; George, Praveen; Kronfli, Anthony; Raithel, Maxwell; Boulos, Francesca; Ghoreishi, Mehrdad; Bittle, Gregory J; Mazzeffi, Michael A; Rubinson, Lewis; Gammie, James S; Griffith, Bartley P; Kon, Zachary N
2018-04-07
Massive pulmonary embolism (PE) remains a highly fatal condition. Although venoarterial extracorporeal membrane oxygenation (VA-ECMO) and surgical pulmonary embolectomy in the management of massive PE have been reported previously, the outcomes remain less than ideal. We hypothesized that the institution of a protocolized approach of triage and optimization using VA-ECMO would result in improved outcomes compared with historical surgical management. All patients with a massive PE referred to the cardiac surgery service between 2010 and 2017 were retrospectively reviewed. Patients were stratified by treatment strategy: historical control versus the protocolized approach. In the historical control group, the primary intervention was surgical pulmonary embolectomy. In the protocol approach group, patients were treated based on an algorithmic approach using VA-ECMO. The primary outcome was 1-year survival. A total of 56 patients (control, n = 27; protocol, n = 29) were identified. All 27 patients in the historical control group underwent surgical pulmonary embolectomy, whereas 2 of 29 patients in the protocol approach group were deemed appropriate for direct surgical pulmonary embolectomy. The remaining 27 patients were placed on VA-ECMO. In the protocol approach group, 15 of 29 patients were treated with anticoagulation alone and 14 patients ultimately required surgical pulmonary embolectomy. One-year survival was significantly lower in the historical control group compared with the protocol approach group (73% vs 96%; P = .02), with no deaths occurring after surgical pulmonary embolectomy in the protocol approach group. A protocolized strategy involving the aggressive institution of VA-ECMO appears to be an effective method to triage and optimize patients with massive PE to recovery or intervention. Implementation of this strategy rather than an aggressive surgical approach may reduce the mortality associated with massive PE. Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
Van Calster, B; Bobdiwala, S; Guha, S; Van Hoorde, K; Al-Memar, M; Harvey, R; Farren, J; Kirk, E; Condous, G; Sur, S; Stalder, C; Timmerman, D; Bourne, T
2016-11-01
A uniform rationalized management protocol for pregnancies of unknown location (PUL) is lacking. We developed a two-step triage protocol to select PUL at high risk of ectopic pregnancy (EP), based on serum progesterone level at presentation (step 1) and the serum human chorionic gonadotropin (hCG) ratio, defined as the ratio of hCG at 48 h to hCG at presentation (step 2). This was a cohort study of 2753 PUL (301 EP), involving a secondary analysis of prospectively and consecutively collected PUL data from two London-based university teaching hospitals. Using a chronological split we used 1449 PUL for development and 1304 for validation. We aimed to assign PUL as low risk with high confidence (high negative predictive value (NPV)) while classifying most EP as high risk (high sensitivity). The first triage step assigned PUL as low risk using a threshold of serum progesterone at presentation. The remaining PUL were triaged using a novel logistic regression risk model based on hCG ratio and initial serum progesterone (second step), defining low risk as an estimated EP risk of < 5%. On validation, initial serum progesterone ≤ 2 nmol/L (step 1) classified 16.1% PUL as low risk. Second-step classification with the risk model selected an additional 46.0% of all PUL as low risk. Overall, the two-step protocol classified 62.1% of PUL as low risk, with an NPV of 98.6% and a sensitivity of 92.0%. When the risk model was used in isolation (i.e. without the first step), 60.5% of PUL were classified as low risk with 99.1% NPV and 94.9% sensitivity. PUL can be classified efficiently into being either high or low risk for complications using a two-step protocol involving initial progesterone and hCG levels and the hCG ratio. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.
An introduction to the Emergency Department Adult Clinical Escalation protocol: ED-ACE.
Coughlan, Eoin; Geary, Una; Wakai, Abel; O'Sullivan, Ronan; Browne, John; McAuliffe, Eilish; Ward, Marie; McDaid, Fiona; Deasy, Conor
2017-09-01
This study demonstrates how a participatory action research approach was used to address the challenge of the early and effective detection of the deteriorating patient in the ED setting. The approach enabled a systematic approach to patient monitoring and escalation of care to be developed to address the wide-ranging spectrum of undifferentiated presentations and the phases of ED care from triage to patient admission. This paper presents a longitudinal patient monitoring system, which aims to provide monitoring and escalation of care, where necessary, of adult patients from triage to admission to hospital in a manner that is feasible in the unique ED environment. An action research approach was taken to designing a longitudinal patient monitoring system appropriate for the ED. While the first draft protocol for post-triage monitoring and escalation was designed by a core research group, six clinical sites were included in iterative cycles of planning, action, reviewing and further planning. Reasons for refining the system at each site were collated and the protocol was adjusted accordingly before commencing the process at the next site. The ED Adult Clinical Escalation longitudinal patient monitoring system (ED-ACE) evolved through iterative cycles of design and testing to include: (1) a monitoring chart for adult patients; (2) a standardised approach to the monitoring and reassessment of patients after triage until they are assessed by a clinician; (3) the ISBAR (I=Identify, S=Situation, B=Background, A=Assessment, R=Recommendation) tool for interprofessional communication relating to clinical escalation; (4) a template for prescribing a patient-specific monitoring plan to be used by treating clinicians to guide patient monitoring from the time the patient is assessed until when they leave the ED and (5) a protocol for clinical escalation prompted by single physiological triggers and clinical concern. This tool offers a link in the 'Chain of Prevention' between the Manchester Triage System and ward-based early warning scores taking account of the importance of standardisation, while being sufficiently adaptable for the unique working environment and patient population in the ED. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Floyd, Liz; Bryce, Fiona; Ramaswamy, Rohit; Olufolabi, Adeyemi; Srofenyoh, Emmanuel; Goodman, David; Pearson, Nancy; Morgan, Kerry; Tetteh, Cecilia; Ahwireng, Victoria; Owen, Medge
2018-06-01
to introduce and embed a midwife-led obstetric triage system in a busy labour ward in Accra, Ghana to improve the quality of care and to reduce delay. the study utilized a participatory action research design. Local staff participated in baseline data collection, the triage training course design and delivery, and post-training monitoring and evaluation. a regional referral hospital in Accra, Ghana undertaking 11,032 deliveries in 2012. all midwives and medical staff. measurements included maternal health outcomes, observations of labour ward activity, structured assessments of midwife actions during admission, waiting times, focus group discussions, and learning needs assessments which informed the course content. During training, two quality improvement tools were developed; coloured risk acuity wristbands and a one page triage assessment form. Participants measured compliance and accuracy in the use of these tools following course completion. initially, no formal triage system was in place. The environment was chaotic with poor compliance to existing protocols. Sixty-two midwives received triage training between 2013 and 2014. Two Triage Champions became responsible for triage implementation, monitoring and further training. Following training, the 'in-charge' midwives recorded a cumulative average of 83.4% of women wearing coloured wristbands. A separate audit by the Triage Champions found that 495/535 (93%) of the wristbands were correctly applied based on the diagnosis. Quarterly monitoring of the triage assessment forms by Kybele trainers, showed that 92% recorded the risk acuity colour, 85% a 'working diagnosis' and 82% a 'plan.' Median (interquartile range) waiting times were reduced from 40 (15-100) to 29 (11-60) minutes (p = 007). Twenty of 25 of the staff reported that the wristbands were helpful. an interactive triage training course led to the development of a triage assessment form and the use of coloured patient wristbands which resulted in delay reduction and improved quality of maternity care. Copyright © 2018 Elsevier Ltd. All rights reserved.
Virtual reality triage training provides a viable solution for disaster-preparedness.
Andreatta, Pamela B; Maslowski, Eric; Petty, Sean; Shim, Woojin; Marsh, Michael; Hall, Theodore; Stern, Susan; Frankel, Jen
2010-08-01
The objective of this study was to compare the relative impact of two simulation-based methods for training emergency medicine (EM) residents in disaster triage using the Simple Triage and Rapid Treatment (START) algorithm, full-immersion virtual reality (VR), and standardized patient (SP) drill. Specifically, are there differences between the triage performances and posttest results of the two groups, and do both methods differentiate between learners of variable experience levels? Fifteen Postgraduate Year 1 (PGY1) to PGY4 EM residents were randomly assigned to two groups: VR or SP. In the VR group, the learners were effectively surrounded by a virtual mass disaster environment projected on four walls, ceiling, and floor and performed triage by interacting with virtual patients in avatar form. The second group performed likewise in a live disaster drill using SP victims. Setting and patient presentations were identical between the two modalities. Resident performance of triage during the drills and knowledge of the START triage algorithm pre/post drill completion were assessed. Analyses included descriptive statistics and measures of association (effect size). The mean pretest scores were similar between the SP and VR groups. There were no significant differences between the triage performances of the VR and SP groups, but the data showed an effect in favor of the SP group performance on the posttest. Virtual reality can provide a feasible alternative for training EM personnel in mass disaster triage, comparing favorably to SP drills. Virtual reality provides flexible, consistent, on-demand training options, using a stable, repeatable platform essential for the development of assessment protocols and performance standards.
Schoolman-Anderson, Kristin; Lane, Roni D; Schunk, Jeff E; Mecham, Nancy; Thomas, Richard; Adelgais, Kathleen
2018-01-16
Pain management guidelines in the emergency department (ED) may reduce time to analgesia administration (TTA). Intranasal fentanyl (INF) is a safe and effective alternative to intravenous opiates. The effect of an ED pain management guideline providing standing orders for nurse-initiated administration of intranasal fentanyl (INF) is not known. The objective of this study was to determine the impact of a pediatric ED triage-based pain protocol utilizing intranasal fentanyl (INF) on time to analgesia administration (TTA) and patient and parent satisfaction. This was a prospective study of patients 3-17 years with an isolated orthopedic injury presenting to a pediatric ED before and after instituting a triage-based pain guideline allowing for administration of INF by triage nurses. Our primary outcome was median TTA and secondary outcomes included the proportion of patients who received INF for pain, had unnecessary IV placement, and patient and parent satisfaction. We enrolled 132 patients; 72 pre-guideline, 60 post-guideline. Demographics were similar between groups. Median TTA was not different between groups (34.5 min vs. 33 min, p = .7). Utilization of INF increased from 41% pre-guideline to 60% post-guideline (p = .01) and unnecessary IV placement decreased from 24% to 0% (p = .002). Patients and parents preferred the IN route for analgesia administration. A triage-based pain protocol utilizing INF did not reduce TTA, but did result in increased INF use, decreased unnecessary IV placement, and was preferred by patients and parents to IV medication. INF is a viable analgesia alternative for children with isolated extremity injuries. Copyright © 2018. Published by Elsevier Inc.
Portable ultrasonography in mass casualty incidents: The CAVEAT examination.
Stawicki, Stanislaw Peter; Howard, James M; Pryor, John P; Bahner, David P; Whitmill, Melissa L; Dean, Anthony J
2010-11-18
Ultrasonography used by practicing clinicians has been shown to be of utility in the evaluation of time-sensitive and critical illnesses in a range of environments, including pre-hospital triage, emergency department, and critical care settings. The increasing availability of light-weight, robust, user-friendly, and low-cost portable ultrasound equipment is particularly suited for use in the physically and temporally challenging environment of a multiple casualty incident (MCI). Currently established ultrasound applications used to identify potentially lethal thoracic or abdominal conditions offer a base upon which rapid, focused protocols using hand-carried emergency ultrasonography could be developed. Following a detailed review of the current use of portable ultrasonography in military and civilian MCI settings, we propose a protocol for sonographic evaluation of the chest, abdomen, vena cava, and extremities for acute triage. The protocol is two-tiered, based on the urgency and technical difficulty of the sonographic examination. In addition to utilization of well-established bedside abdominal and thoracic sonography applications, this protocol incorporates extremity assessment for long-bone fractures. Studies of the proposed protocol will need to be conducted to determine its utility in simulated and actual MCI settings.
TH-C-18A-08: A Management Tool for CT Dose Monitoring, Analysis, and Protocol Review
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, J; Chan, F; Newman, B
2014-06-15
Purpose: To develop a customizable tool for enterprise-wide managing of CT protocols and analyzing radiation dose information of CT exams for a variety of quality control applications Methods: All clinical CT protocols implemented on the 11 CT scanners at our institution were extracted in digital format. The original protocols had been preset by our CT management team. A commercial CT dose tracking software (DoseWatch,GE healthcare,WI) was used to collect exam information (exam date, patient age etc.), scanning parameters, and radiation doses for all CT exams. We developed a Matlab-based program (MathWorks,MA) with graphic user interface which allows to analyze themore » scanning protocols with the actual dose estimates, and compare the data to national (ACR,AAPM) and internal reference values for CT quality control. Results: The CT protocol review portion of our tool allows the user to look up the scanning and image reconstruction parameters of any protocol on any of the installed CT systems among about 120 protocols per scanner. In the dose analysis tool, dose information of all CT exams (from 05/2013 to 02/2014) was stratified on a protocol level, and within a protocol down to series level, i.e. each individual exposure event. This allows numerical and graphical review of dose information of any combination of scanner models, protocols and series. The key functions of the tool include: statistics of CTDI, DLP and SSDE, dose monitoring using user-set CTDI/DLP/SSDE thresholds, look-up of any CT exam dose data, and CT protocol review. Conclusion: our inhouse CT management tool provides radiologists, technologists and administration a first-hand near real-time enterprise-wide knowledge on CT dose levels of different exam types. Medical physicists use this tool to manage CT protocols, compare and optimize dose levels across different scanner models. It provides technologists feedback on CT scanning operation, and knowledge on important dose baselines and thresholds.« less
1984-02-06
MASS CASUALTY SITUATIONS FINAL REPORT for 0O FEDERAL EMERGENCY MANAGEMENT AGENCY WASHINGTON, D.C. 20472 FEMA CONTRACT NUMBER EMW-C-1202 e FEMA WORK UNIT...20006 FINAL REPORT for FEDERAL EMERGENCY MANAGEMENT AGENCY WASHINGTON, D.C. 20472 FEMA CONTRACT NUMBER EMW-C-1202 FEMA WORK UNIT NUMBER 2412G...February 1984 This repnrt has been reviewed in the Federal Emergency Management Agency and approved for publication. Approval does not signify that the
Christian, Michael D; Sprung, Charles L; King, Mary A; Dichter, Jeffrey R; Kissoon, Niranjan; Devereaux, Asha V; Gomersall, Charles D
2014-10-01
Pandemics and disasters can result in large numbers of critically ill or injured patients who may overwhelm available resources despite implementing surge-response strategies. If this occurs, critical care triage, which includes both prioritizing patients for care and rationing scarce resources, will be required. The suggestions in this chapter are important for all who are involved in large-scale pandemics or disasters with multiple critically ill or injured patients, including front-line clinicians, hospital administrators, and public health or government officials. The Triage topic panel reviewed previous task force suggestions and the literature to identify 17 key questions for which specific literature searches were then conducted to identify studies upon which evidence-based recommendations could be made. No studies of sufficient quality were identified. Therefore, the panel developed expert opinion-based suggestions using a modified Delphi process. Suggestions from the previous task force that were not being updated were also included for validation by the expert panel. The suggestions from the task force outline the key principles upon which critical care triage should be based as well as a path for the development of the plans, processes, and infrastructure required. This article provides 11 suggestions regarding the principles upon which critical care triage should be based and policies to guide critical care triage. Ethical and efficient critical care triage is a complex process that requires significant planning and preparation. At present, the prognostic tools required to produce an effective decision support system (triage protocol) as well as the infrastructure, processes, legal protections, and training are largely lacking in most jurisdictions. Therefore, critical care triage should be a last resort after mass critical care surge strategies.
van Rein, Eveline A J; van der Sluijs, Rogier; Houwert, R Marijn; Gunning, Amy C; Lichtveld, Rob A; Leenen, Luke P H; van Heijl, Mark
2018-01-27
In an optimal trauma system, prehospital trauma triage ensures transport of the right patient to the right hospital. Incorrect triage results in undertriage and overtriage. The aim of this systematic review is to evaluate and compare prehospital trauma triage system quality worldwide and determine effectiveness in terms of undertriage and overtriage for trauma patients. A systematic search of Pubmed/MEDLINE, Embase, and Cochrane Library databases was performed, using "trauma", "trauma center," or "trauma system", combined with "triage", "undertriage," or "overtriage", as search terms. All studies describing ground transport and actual destination hospital of patients with and without severe injuries, using prehospital triage, published before November 2017, were eligible for inclusion. To assess the quality of these studies, a critical appraisal tool was developed. A total of 33 articles were included. The percentage of undertriage ranged from 1% to 68%; overtriage from 5% to 99%. Older age and increased geographical distance were associated with undertriage. Mortality was lower for severely injured patients transferred to a higher-level trauma center. The majority of the included studies were of poor methodological quality. The studies of good quality showed poor performance of the triage protocol, but additional value of EMS provider judgment in the identification of severely injured patients. In most of the evaluated trauma systems, a substantial part of the severely injured patients is not transported to the appropriate level trauma center. Future research should come up with new innovative ways to improve the quality of prehospital triage in trauma patients. Copyright © 2018. Published by Elsevier Inc.
Initial resuscitation for Australasian Triage Scale 2 patients in a Nepalese emergency department.
Basnet, Bibhusan; Bhandari, Rabin; Moore, Malcolm
2012-08-01
Triage is recognized as important in providing timely care to emergency patients. However, systematic triage is only practised in two EDs in Nepal. The first objective of this study was to assess the performance of one of these departments in seeing triaged patients in a timely fashion. Second, an epidemiological survey of patients presenting to the ED was performed to describe the conditions seen and initial resuscitation undertaken. We performed a descriptive cross-sectional study in the ED of B.P. Koirala Institute of Health Sciences, eastern Nepal where the Australasian Triage Scale (ATS) is used. One hundred and sixty patients triaged as ATS 2 were recruited. The time taken for the duty doctor to see the patient was noted. The presenting problems, vital signs and level of consciousness were measured at presentation. The resuscitation measures were recorded. The mean waiting time was 2.1 ± 1.7 min with a range of 1-10 min, which meets the benchmark for ATS 2. At triage, the most common presenting problems were circulatory shock (23.1%), altered consciousness (21%), respiratory difficulty (16.9%) and poisoning (15%). Oxygen, i.v. fluids and antibiotics were the most common therapies used in the initial resuscitation of patients. Patients triaged as ATS 2 were seen in a timely fashion. Seriously ill patients requiring resuscitation present commonly to this ED. This is a big challenge for junior doctors. Improved training, treatment protocols and equipment are needed to help manage this burden. © 2012 The Authors. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.
ED Triage Process Improvement: Timely Vital Signs for Less Acute Patients.
Falconer, Stella S; Karuppan, Corinne M; Kiehne, Emily; Rama, Shravan
2018-06-13
Vital signs can result in an upgrade of patients' Emergency Severity Index (ESI) levels. It is therefore preferable to obtain vital signs early in the triage process, particularly for ESI level 3 patients. Emergency departments have an opportunity to redesign triage processes to meet required protocols while enhancing the quality and experience of care. We performed process analyses to redesign the door-to-vital signs process. We also developed spaghetti diagrams to reconfigure the patient arrival area. The door-to-vital signs time was reduced from 43.1 minutes to 6.44 minutes. Both patients and triage staff seemed more satisfied with the new process. The patient arrival area was less congested and more welcoming. Performing activities in parallel reduces flow time with no additional resources. Staff involvement in process planning, redesign, and control ensures engagement and early buy-in. One should anticipate how changes to one process might affect other processes. Copyright © 2018. Published by Elsevier Inc.
Serious gaming technology in major incident triage training: a pragmatic controlled trial.
Knight, James F; Carley, Simon; Tregunna, Bryan; Jarvis, Steve; Smithies, Richard; de Freitas, Sara; Dunwell, Ian; Mackway-Jones, Kevin
2010-09-01
By exploiting video games technology, serious games strive to deliver affordable, accessible and usable interactive virtual worlds, supporting applications in training, education, marketing and design. The aim of the present study was to evaluate the effectiveness of such a serious game in the teaching of major incident triage by comparing it with traditional training methods. Pragmatic controlled trial. During Major Incident Medical Management and Support Courses, 91 learners were randomly distributed into one of two training groups: 44 participants practiced triage sieve protocol using a card-sort exercise, whilst the remaining 47 participants used a serious game. Following the training sessions, each participant undertook an evaluation exercise, whereby they were required to triage eight casualties in a simulated live exercise. Performance was assessed in terms of tagging accuracy (assigning the correct triage tag to the casualty), step accuracy (following correct procedure) and time taken to triage all casualties. Additionally, the usability of both the card-sort exercise and video game were measured using a questionnaire. Tagging accuracy by participants who underwent the serious game training was significantly higher than those who undertook the card-sort exercise [Chi2=13.126, p=0.02]. Step accuracy was also higher in the serious game group but only for the numbers of participants that followed correct procedure when triaging all eight casualties [Chi2=5.45, p=0.0196]. There was no significant difference in time to triage all casualties (card-sort=435+/-74 s vs video game=456+/-62 s, p=0.155). Serious game technologies offer the potential to enhance learning and improve subsequent performance when compared to traditional educational methods. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.
HPV testing with cytology triage for cervical cancer screening in routine practice.
Louvanto, Karolina; Chevarie-Davis, Myriam; Ramanakumar, Agnihotram Venkata; Franco, Eduardo Luis; Ferenczy, Alex
2014-05-01
The purpose of this study was to evaluate the feasibility and effectiveness of Viral Testing Alone with Pap (Papanicolaou) Triage for Screening Cervical Cancer in Routine Practice (VASCAR) in a publicly funded university-affiliated hospital in Montreal, Canada. Women who are 30-65 years old are screened with the Hybrid Capture-2 assay. Women with negative results are retested at 3-year intervals; women with positive results are triaged with conventional cytologic methods. Women with Papanicolaou positive test results (≥atypical squamous cells of undetermined significance) are referred to colposcopy; women with Papanicolaou negative test results are retested with Hybrid Capture-2 assay and a Papanicolaou test in 1 year. Results were compared with a historic era (annual cytology with ≥atypical squamous cells of undetermined significance threshold for colposcopy referral) in the 3 years before VASCAR. VASCAR included 23,739 eligible women, among whom 1646 women (6.9%) tested positive for the human papillomavirus (HPV). Because of the need for subsequent sampling for cytologic testing, follow-up evaluation for cytologic triage was relatively poor; only 46% and 24% of HPV-positive women were Papanicolaou-triaged and underwent biopsy, respectively. Protocol violations occurred mainly in the early phases of implementation (12%). Detection of high-grade cervical intraepithelial neoplasia increased nearly 3-fold (rate ratio, 2.78; 95% confidence interval [CI], 2.1-3.7) during VASCAR, mostly because of a doubling in the rate of high-grade cervical intraepithelial neoplasia (34.0%; 95% CI, 21.2-48.8) compared with the historic cytology-only era (16.3%; 95% CI, 13.2-19.8). VASCAR reduced the median time to colposcopy from a positive screen from 11 months (95% CI, 10.48-11.50) to 3 months (95% CI, 2.64-3.80). VASCAR is feasible; however, it requires cosampling for HPV and cytology and for continuous education of healthcare providers of the HPV-Papanicolaou triage protocol. Efficacy in disease detection and reduction in time to colposcopy referrals compared with the historic cytology era is encouraging but should be considered preliminary because of the small number of patients who were tested. Copyright © 2014 Mosby, Inc. All rights reserved.
Sarmiento, Kelly; Eckstein, Daniel; Zambon, Allison
2013-03-01
In an effort to encourage appropriate field triage procedures, the Centers for Disease Control and Prevention (CDC), in collaboration with the National Highway Traffic Safety Administration and the American College of Surgeons-Committee on Trauma, convened the National Expert Panel on Field Triage to update the Field Triage Decision Scheme: The National Trauma Triage Protocol (Decision Scheme). In support of the Decision Scheme, CDC developed educational resources for emergency medical service (EMS) professionals, one of CDC's first efforts to develop and broadly disseminate educational information for the EMS community. CDC wanted to systematically collect information from the EMS community on what worked and what did not with respect to these educational materials and which materials were of most use. An evaluation was conducted to obtain feedback from EMS professionals about the Decision Scheme and use of Decision Scheme educational materials. The evaluation included a survey and a series of focus groups. Findings indicate that a segment of the Decision Scheme's intended audience is using the materials and learning from them, and they have had a positive influence on their triage practices. However, many of the individuals who participated in this research are not using the Decision Scheme and indicated that the materials have not affected their triage practices. Findings presented in this article can be used to inform development and distribution of additional Decision Scheme educational resources to ensure they reach a greater proportion of EMS professionals and to inform other education and dissemination efforts with the EMS community.
Gómez-Jiménez, Josep; Becerra, Oscar; Boneu, Francisco; Burgués, Lluís; Pàmies, Salvador
2006-01-01
Structured emergency department (ED) triage scales can be used to develop patient referral strategies from the ED to primary care. The objectives of the present study were to evaluate the percentage of patients who could potentially be referred from triage to primary care and to describe their clinical characteristics. We analyzed all patients with low acuity (triage levels IV and V) and low complexity (patients discharged from the ED) triaged during 2003 with the Andorran Triage Model in the ED and estimated the percentage of patients who could potentially be referred on the basis of three primary care models: A, centers unable to deal with emergencies or perform complementary investigations; B, centers able to deal with emergencies and perform complementary investigations, and C, centers able to deal with emergencies but unable to perform complementary investigations. Of the 25,319 patients included in the study, 5.63% could be referred to model A, 75.22% to model B and 33.36% to model C. A total of 81.04% of these model C patients were classified in seven symptomatic categories: wounds and traumatisms, inflammation or fever, pediatric problems, rhinolaryngological infection or alterations, ocular symptoms, pain and cutaneous allergy or reactions. Casemix analysis, based on the level of acuity and discharge criteria, can be used to establish the percentage of patients that could potentially be referred to primary care. Analysis of their clinical profile is useful to design referral protocols.
Olszewski, R; Frison, L; Wisniewski, M; Denis, J M; Vynckier, S; Cosnard, G; Zech, F; Reychler, H
2013-01-01
The purpose of this study is to compare the reproducibility of three-dimensional cephalometric landmarks on three-dimensional computed tomography (3D-CT) surface rendering using clinical protocols based on low-dose (35-mAs) spiral CT and cone-beam CT (I-CAT). The absorbed dose levels for radiosensitive organs in the maxillofacial region during exposure in both 3D-CT protocols were also assessed. The study population consisted of ten human dry skulls examined with low-dose CT and cone-beam CT. Two independent observers identified 24 cephalometric anatomic landmarks at 13 sites on the 3D-CT surface renderings using both protocols, with each observer repeating the identification 1 month later. A total of 1,920 imaging measurements were performed. Thermoluminescent dosimeters were placed at six sites around the thyroid gland, the submandibular glands, and the eyes in an Alderson phantom to measure the absorbed dose levels. When comparing low-dose CT and cone-beam CT protocols, the cone-beam CT protocol proved to be significantly more reproducible for four of the 13 anatomical sites. There was no significant difference between the protocols for the other nine anatomical sites. Both low-dose and cone-beam CT protocols were equivalent in dose absorption to the eyes and submandibular glands. However, thyroid glands were more irradiated with low-dose CT. Cone-beam CT was more reproducible and procured less irradiation to the thyroid gland than low-dose CT. Cone-beam CT should be preferred over low-dose CT for developing three-dimensional bony cephalometric analyses.
Predicting Ebola infection: A malaria-sensitive triage score for Ebola virus disease
Okoni-Williams, Harry Henry; Suma, Mohamed; Mancuso, Brooke; Al-Dikhari, Ahmed; Faouzi, Mohamed
2017-01-01
Background The non-specific symptoms of Ebola Virus Disease (EVD) pose a major problem to triage and isolation efforts at Ebola Treatment Centres (ETCs). Under the current triage protocol, half the patients allocated to high-risk “probable” wards were EVD(-): a misclassification speculated to predispose nosocomial EVD infection. A better understanding of the statistical relevance of individual triage symptoms is essential in resource-poor settings where rapid, laboratory-confirmed diagnostics are often unavailable. Methods/Principal findings This retrospective cohort study analyses the clinical characteristics of 566 patients admitted to the GOAL-Mathaska ETC in Sierra Leone. The diagnostic potential of each characteristic was assessed by multivariate analysis and incorporated into a statistically weighted predictive score, designed to detect EVD as well as discriminate malaria. Of the 566 patients, 28% were EVD(+) and 35% were malaria(+). Malaria was 2-fold more common in EVD(-) patients (p<0.05), and thus an important differential diagnosis. Univariate analyses comparing EVD(+) vs. EVD(-) and EVD(+)/malaria(-) vs. EVD(-)/malaria(+) cohorts revealed 7 characteristics with the highest odds for EVD infection, namely: reported sick-contact, conjunctivitis, diarrhoea, referral-time of 4–9 days, pyrexia, dysphagia and haemorrhage. Oppositely, myalgia was more predictive of EVD(-) or EVD(-)/malaria(+). Including these 8 characteristics in a triage score, we obtained an 89% ability to discriminate EVD(+) from either EVD(-) or EVD(-)/malaria(+). Conclusions/Significance This study proposes a highly predictive and easy-to-use triage tool, which stratifies the risk of EVD infection with 89% discriminative power for both EVD(-) and EVD(-)/malaria(+) differential diagnoses. Improved triage could preserve resources by identifying those in need of more specific differential diagnostics as well as bolster infection prevention/control measures by better compartmentalizing the risk of nosocomial infection. PMID:28231242
Predicting Ebola infection: A malaria-sensitive triage score for Ebola virus disease.
Hartley, Mary-Anne; Young, Alyssa; Tran, Anh-Minh; Okoni-Williams, Harry Henry; Suma, Mohamed; Mancuso, Brooke; Al-Dikhari, Ahmed; Faouzi, Mohamed
2017-02-01
The non-specific symptoms of Ebola Virus Disease (EVD) pose a major problem to triage and isolation efforts at Ebola Treatment Centres (ETCs). Under the current triage protocol, half the patients allocated to high-risk "probable" wards were EVD(-): a misclassification speculated to predispose nosocomial EVD infection. A better understanding of the statistical relevance of individual triage symptoms is essential in resource-poor settings where rapid, laboratory-confirmed diagnostics are often unavailable. This retrospective cohort study analyses the clinical characteristics of 566 patients admitted to the GOAL-Mathaska ETC in Sierra Leone. The diagnostic potential of each characteristic was assessed by multivariate analysis and incorporated into a statistically weighted predictive score, designed to detect EVD as well as discriminate malaria. Of the 566 patients, 28% were EVD(+) and 35% were malaria(+). Malaria was 2-fold more common in EVD(-) patients (p<0.05), and thus an important differential diagnosis. Univariate analyses comparing EVD(+) vs. EVD(-) and EVD(+)/malaria(-) vs. EVD(-)/malaria(+) cohorts revealed 7 characteristics with the highest odds for EVD infection, namely: reported sick-contact, conjunctivitis, diarrhoea, referral-time of 4-9 days, pyrexia, dysphagia and haemorrhage. Oppositely, myalgia was more predictive of EVD(-) or EVD(-)/malaria(+). Including these 8 characteristics in a triage score, we obtained an 89% ability to discriminate EVD(+) from either EVD(-) or EVD(-)/malaria(+). This study proposes a highly predictive and easy-to-use triage tool, which stratifies the risk of EVD infection with 89% discriminative power for both EVD(-) and EVD(-)/malaria(+) differential diagnoses. Improved triage could preserve resources by identifying those in need of more specific differential diagnostics as well as bolster infection prevention/control measures by better compartmentalizing the risk of nosocomial infection.
Mohan, Deepika; Rosengart, Matthew R; Fischhoff, Baruch; Angus, Derek C; Farris, Coreen; Yealy, Donald M; Wallace, David J; Barnato, Amber E
2016-11-11
Between 30 and 40 % of patients with severe injuries receive treatment at non-trauma centers (under-triage), largely because of physician decision making. Existing interventions to improve triage by physicians ignore the role that intuition (heuristics) plays in these decisions. One such heuristic is to form an initial impression based on representativeness (how typical does a patient appear of one with severe injuries). We created a video game (Night Shift) to recalibrate physician's representativeness heuristic in trauma triage. We developed Night Shift in collaboration with emergency medicine physicians, trauma surgeons, behavioral scientists, and game designers. Players take on the persona of Andy Jordan, an emergency medicine physician, who accepts a new job in a small town. Through a series of cases that go awry, they gain experience with the contextual cues that distinguish patients with minor and severe injuries (based on the theory of analogical encoding) and receive emotionally-laden feedback on their performance (based on the theory of narrative engagement). The planned study will compare the effect of Night Shift with that of an educational program on physician triage decisions and on physician heuristics. Psychological theory predicts that cognitive load increases reliance on heuristics, thereby increasing the under-triage rate when heuristics are poorly calibrated. We will randomize physicians (n = 366) either to play the game or to review an educational program, and will assess performance using a validated virtual simulation. The validated simulation includes both control and cognitive load conditions. We will compare rates of under-triage after exposure to the two interventions (primary outcome) and will compare the effect of cognitive load on physicians' under-triage rates (secondary outcome). We hypothesize that: a) physicians exposed to Night Shift will have lower rates of under-triage compared to those exposed to the educational program, and b) cognitive load will not degrade triage performance among physicians exposed to Night Shift as much as it will among those exposed to the educational program. Serious games offer a new approach to the problem of poorly-calibrated heuristics in trauma triage. The results of this trial will contribute to the understanding of physician quality improvement and the efficacy of video games as behavioral interventions. clinicaltrials.gov; NCT02857348 ; August 2, 2016.
O'Donnell, C; Iino, M; Mansharan, K; Leditscke, J; Woodford, N
2011-02-25
CT scanning of the deceased is an established technique performed on all individuals admitted to VIFM over the last 5 years. It is used primarily to assist pathologists in determining cause and manner of death but is also invaluable for identification of unknown deceased individuals where traditional methods are not possible. Based on this experience, CT scanning was incorporated into phase 2 of the Institute's DVI process for the 2009 Victorian bushfires. All deceased individuals and fragmented remains admitted to the mortuary were CT scanned in their body bags using established protocols. Images were reviewed by 2 teams of 2 radiologists experienced in forensic imaging and the findings transcribed onto a data sheet constructed specifically for the DVI exercise. The contents of 255 body bags were examined in the 28 days following the fires. 164 missing persons were included in the DVI process with 163 deceased individuals eventually identified. CT contributed to this identification in 161 persons. In 2 cases, radiologists were unable to recognize commingled remains. CT was utilized in the initial triage of each bag's contents. If radiological evaluation determined that bodies were incomplete then this information was provided to search teams who revisited the scenes of death. CT was helpful in differentiation of human from non-human remains in 8 bags, recognition of human/animal commingling in 10 bags and human commingling in 6 bags. In 61% of cases gender was able to be determined on CT using a novel technique of genitalia detection and in all but 2 cases this was correct. Age range was able to be determined on CT in 94% with an accuracy of 76%. Specific identification features detected on CT included the presence of disease (14 disease entities in 13 cases), medical devices (26 devices in 19 cases) and 274 everyday metallic items associated with the remains of 135 individuals. CT scanning provided useful information prior to autopsy by flagging likely findings including the presence of non-human remains, at the time of autopsy by assisting in the localization of identifying features in heavily disfigured bodies, and after autopsy by retrospective review of images for clarification of issues that arose at the time of pathologist case review. In view of the success of CT scanning in this mass disaster, DVI administrators should explore the incorporation of CT services into their disaster plans. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
TIA triage in emergency department using acute MRI (TIA-TEAM): a feasibility and safety study.
Vora, Nirali; Tung, Christie E; Mlynash, Michael; Garcia, Madelleine; Kemp, Stephanie; Kleinman, Jonathan; Zaharchuk, Greg; Albers, Gregory; Olivot, Jean-Marc
2015-04-01
Positive diffusion weighted imaging (DWI) on MRI is associated with increased recurrent stroke risk in TIA patients. Acute MRI aids in TIA risk stratification and diagnosis. To evaluate the feasibility and safety of TIA triage directly from the emergency department (ED) with acute MRI and neurological consultation. Consecutive ED TIA patients assessed by a neurologist underwent acute MRI/MRA of head/neck per protocol and were hospitalized if positive DWI, symptomatic vessel stenosis, or per clinical judgment. Stroke neurologist adjudicated the final TIA diagnosis as definite, possible, or not a cerebrovascular event. Stroke recurrence rates were calculated at 7, 90, 365 days and compared with predicted stroke rates derived from historical DWI and ABCD(2) score data. One hundred twenty-nine enrolled patients had a mean age of 69 years (± 17) and median ABCD(2) score of 3 (interquartile range [IQR] 3-4). During triage, 112 (87%) patients underwent acute MRI after a median of 16 h (IQR 10-23) from symptom onset. No patients experienced a recurrent event before imaging. Twenty-four (21%) had positive DWI and 8 (7%) had symptomatic vessel stenosis. Of the total cohort, 83 (64%) were discharged and 46 (36%) were hospitalized. By one-year follow-up, one patient in each group had experienced a stroke. Of 92 patients with MRI and index cerebrovascular event, recurrent stroke rates were 1.1% at 7 and 90 days. These were similar to predicted recurrence rates. TIA triage in the ED using a protocol with neurological consultation and acute MRI is feasible and safe. The majority of patients were discharged without hospitalization and rates of recurrent stroke were not higher than predicted. © 2014 World Stroke Organization.
2013-01-01
Background Pain experienced by children in emergency departments (EDs) is often poorly assessed and treated. Although local protocols and strategies are important to ensure appropriate staff behaviours, few studies have focussed on pain management policies at hospital or department level. This study aimed at describing the policies and reported practices of pain assessment and treatment in a national sample of Italian pediatric EDs, and identifying the assocoated structural and organisational factors. Methods A structured questionnaire was mailed to all the 14 Italian pediatric and maternal and child hospitals and to 5 general hospitals with separate pediatric emergency room. There were no refusals. Information collected included the frequency and mode of pain assessment, presence of written pain management protocols, use of local anaesthetic (EMLA cream) before venipuncture, and role of parents. General data on the hospital and ED were also recorded. Multiple Correspondence Analysis was used to explore the multivariable associations between the characteristics of hospitals and EDs and their pain management policies and practices. Results Routine pain assessment both at triage and in the emergency room was carried out only by 26% of surveyed EDs. About one third did not use algometric scales, and almost half (47.4%) did not have local protocols for pain treatment. Only 3 routinely reassessed pain after treatment, and only 2 used EMLA. All EDs allowed parents’ presence and most (17, 89.9%) allowed them to stay when painful procedures were carried out. Eleven hospitals (57.9%) allowed parents to hold their child during blood sampling. Pediatric and maternal and child hospitals, those located in the North of Italy, equipped with medico-surgical-traumatological ED and short stay observation, and providing full assessment triage over 24 hours were more likely to report appropriate policies for pain management both at triage and in ER. A nurses to admissions ratio ≥ median was associated with better pain management at triage. Conclusions Despite availability of national and international guidelines, pediatric pain management is still sub-optimal in Italian emergency departments. Multifaceted strategies including development of local policies, staff educational programs, and parental involvement in pain assessment should be carried out and periodically reinforced. PMID:24020369
Triage sepsis alert and sepsis protocol lower times to fluids and antibiotics in the ED.
Hayden, Geoffrey E; Tuuri, Rachel E; Scott, Rachel; Losek, Joseph D; Blackshaw, Aaron M; Schoenling, Andrew J; Nietert, Paul J; Hall, Greg A
2016-01-01
Early identification of sepsis in the emergency department (ED), followed by adequate fluid hydration and appropriate antibiotics, improves patient outcomes. We sought to measure the impact of a sepsis workup and treatment protocol (SWAT) that included an electronic health record (EHR)-based triage sepsis alert, direct communication, mobilization of resources, and standardized order sets. We conducted a retrospective, quasiexperimental study of adult ED patients admitted with suspected sepsis, severe sepsis, or septic shock. We defined a preimplementation (pre-SWAT) group and a postimplementation (post-SWAT) group and further broke these down into SWAT A (septic shock) and SWAT B (sepsis with normal systolic blood pressure). We performed extensive data comparisons in the pre-SWAT and post-SWAT groups, including demographics, systemic inflammatory response syndrome criteria, time to intravenous fluids bolus, time to antibiotics, length-of-stay times, and mortality rates. There were 108 patients in the pre-SWAT group and 130 patients in the post-SWAT group. The mean time to bolus was 31 minutes less in the postimplementation group, 51 vs 82 minutes (95% confidence interval, 15-46; P value < .01). The mean time to antibiotics was 59 minutes less in the postimplementation group, 81 vs 139 minutes (95% confidence interval, 44-74; P value < .01). Segmented regression modeling did not identify secular trends in these outcomes. There was no significant difference in mortality rates. An EHR-based triage sepsis alert and SWAT protocol led to a significant reduction in the time to intravenous fluids and time to antibiotics in ED patients admitted with suspected sepsis, severe sepsis, and septic shock. Copyright © 2015 Elsevier Inc. All rights reserved.
Optimization of the scan protocols for CT-based material extraction in small animal PET/CT studies
NASA Astrophysics Data System (ADS)
Yang, Ching-Ching; Yu, Jhih-An; Yang, Bang-Hung; Wu, Tung-Hsin
2013-12-01
We investigated the effects of scan protocols on CT-based material extraction to minimize radiation dose while maintaining sufficient image information in small animal studies. The phantom simulation experiments were performed with the high dose (HD), medium dose (MD) and low dose (LD) protocols at 50, 70 and 80 kVp with varying mA s. The reconstructed CT images were segmented based on Hounsfield unit (HU)-physical density (ρ) calibration curves and the dual-energy CT-based (DECT) method. Compared to the (HU;ρ) method performed on CT images acquired with the 80 kVp HD protocol, a 2-fold improvement in segmentation accuracy and a 7.5-fold reduction in radiation dose were observed when the DECT method was performed on CT images acquired with the 50/80 kVp LD protocol, showing the possibility to reduce radiation dose while achieving high segmentation accuracy.
The need for pediatric-specific triage criteria: results from the Florida Trauma Triage Study.
Phillips, S; Rond, P C; Kelly, S M; Swartz, P D
1996-12-01
The objective of the Florida Trauma Triage Study was to assess the performance of state-adopted field triage criteria. The study addressed three specific age groups: pediatric (age < 15 years), adult (age 15-54 years), and geriatric (age 55+ years). Since 1990, Florida has used a uniform set of eight triage criteria, known as the trauma scorecard, for triaging adult trauma patients to state-approved trauma centers. However, only five of the criteria are recommended for use with pediatric patients. This article presents the findings regarding the performance of the scorecard when applied to a pediatric population. We used state trauma registry data linked to state hospital discharge data in a retrospective analysis of trauma patients transported by prehospital providers to any acute care hospital within nine selected Florida counties between July 1, 1991, and December 31, 1991. We used cross-table and logistic regression analysis to determine the ability of triage criteria to correctly identify patients who were retrospectively defined as major trauma. We applied the field criteria to physiologic and anatomy/mechanism of injury data contained in the trauma registry to "score" the patient as major or minor trauma. To make our retrospective determination of major or minor trauma we used the protocols developed by an expert medical panel as described by E. J. MacKenzie et al. (1990). We calculated sensitivity, specificity, and the corresponding over- and undertriage rates by comparing patient classifications (major or minor trauma) produced by the triage criteria and the retrospective algorithm. We used logistic regression to identify which triage criteria were statistically significant in predicting major trauma. Pediatric cases accounted for 9.2% of the total study population, 6.0% of all hospitalized cases, and 6.8% of all trauma deaths. Of the 1505 pediatric cases available for analysis, the triage criteria classified 269 cases as expected major trauma and 1236 cases as expected minor trauma. The retrospective algorithm classified 78 cases as expected major trauma and 1427 cases as expected minor trauma. The resulting specificity is 84.8% (15.2% overtriage), and the sensitivity is 66.7% (33.3% undertriage). Logistic regression indicated that, of the eight state-adopted field triage criteria, only the Glasgow coma score, ejection from vehicle, and penetrating injuries have a statistically significant impact on predicting major trauma in pediatric patients. Although the state-adopted trauma scorecard, applied to a pediatric population, produced acceptable overtriage, it did not produce acceptable undertriage. However, our undertriage rate is comparable to the results of other published studies on pediatric trauma. As a result of the Florida Trauma Triage Study, a new pediatric triage instrument was developed. It is currently being field-tested.
Koo, M; Sabaté, A; Magalló, P; García, M A; Domínguez, J; de Lama, M E; López, S
2011-11-01
To assess conservative treatment of splenic injury due to trauma, following a protocol for computed tomography (CT) and angiographic embolization. To quantify the predictive value of CT for detecting bleeding and need for embolization. The care protocol developed by the multidisciplinary team consisted of angiography with embolization of lesions revealed by contrast extravasation under CT as well as embolization of grade III-V injuries observed, or grade I-II injuries causing hemodynamic instability and/or need for blood transfusion. We collected data on demographic variables, injury severity score (ISS), angiographic findings, and injuries revealed by CT. Pre-protocol and post-protocol outcomes were compared. The sensitivity and specificity of CT findings were calculated for all patients who required angiographic embolization. Forty-four and 30 angiographies were performed in the pre- and post-protocol periods, respectively. The mean (SD) ISSs in the two periods were 25 (11) and 26 (12), respectively. A total of 24 (54%) embolizations were performed in the pre-protocol period and 28 (98%) after implementation of the protocol. Two and 7 embolizations involved the spleen in the 2 periods, respectively; abdominal laparotomies numbered 32 and 25, respectively, and 10 (31%) vs 4 (16%) splenectomies were performed. The specificity and sensitivity values for contrast extravasation found on CT and followed by embolization were 77.7% and 79.5%. The implementation of this multidisciplinary protocol using CT imaging and angiographic embolization led to a decrease in the number of splenectomies. The protocol allows us to take a more conservative treatment approach.
Ibáñez, Raquel; Moreno-Crespi, Judit; Sardà, Montserrat; Autonell, Josefina; Fibla, Montserrat; Gutiérrez, Cristina; Lloveras, Belen; Alejo, María; Català, Isabel; Alameda, Francesc; Casas, Miquel; Bosch, F Xavier; de Sanjosé, Silvia
2012-01-26
A protocol for cervical cancer screening among sexually active women 25 to 65 years of age was introduced in 2006 in Catalonia, Spain to increase coverage and to recommend a 3-year-interval between screening cytology. In addition, Human Papillomavirus (HPV) was offered as a triage test for women with a diagnosis of atypical squamous cells of undetermined significance (ASC-US). HPV testing was recommended within 3 months of ASC-US diagnosis. According to protocol, HPV negative women were referred to regular screening including a cytological exam every 3 years while HPV positive women were referred to colposcopy and closer follow-up. We evaluated the implementation of the protocol and the prediction of HPV testing as a triage tool for cervical intraepithelial lesions grade two or worse (CIN2+) in women with a cytological diagnosis of ASC-US. During 2007-08 a total of 611 women from five reference laboratories in Catalonia with a novel diagnosis of ASC-US were referred for high risk HPV (hrHPV) triage using high risk Hybrid Capture version 2. Using routine record linkage data, women were followed for 3 years to evaluate hrHPV testing efficacy for predicting CIN2+ cases. Logistic regression analysis was used to estimate the odds ratio for CIN2 +. Among the 611 women diagnosed with ASC-US, 493 (80.7%) had at least one follow-up visit during the study period. hrHPV was detected in 48.3% of the women at study entry (mean age 35.2 years). hrHPV positivity decreased with increasing age from 72.6% among women younger than 25 years to 31.6% in women older than 54 years (p < 0.01). At the end of the 3 years follow-up period, 37 women with a diagnosis of CIN2+ (18 CIN2, 16 CIN3, 2 cancers, and 1 with high squamous intraepithelial lesions--HSIL) were identified and all but one had a hrHPV positive test at study entry. Sensitivity to detect CIN2+ of hrHPV was 97.2% (95%confidence interval (CI) = 85.5-99.9) and specificity was 68.3% (95%CI = 63.1-73.2). The odds ratio for CIN2+ was 45.3 (95% CI: 6.2-333.0), when among ASC-US hrHPV positive women were compared to ASC-US hrHPV negative women. Triage of ASC-US with hrHPV testing showed a high sensitivity for the detection of CIN2+ and a high negative predictive value after 3 years of follow-up. The results of this study are in line with the current guidelines for triage of women with ASC-US in the target age range of 25-65. Non adherence to guidelines will lead to unnecessary medical interventions. Further investigation is needed to improve specificity of ASC-US triage.
Brown, Joshua B; Gestring, Mark L; Forsythe, Raquel M; Stassen, Nicole A; Billiar, Timothy R; Peitzman, Andrew B; Sperry, Jason L
2015-02-01
Undertriage is a concern in geriatric patients. The National Trauma Triage Protocol (NTTP) recognized that systolic blood pressure (SBP) less than 110 mm Hg may represent shock in those older than 65 years. The objective was to evaluate the impact of substituting an SBP of less than 110 mm Hg for the current SBP of less than 90 mm Hg criterion within the NTTP on triage performance and mortality. Subjects undergoing scene transport in the National Trauma Data Bank (2010-2012) were included. The outcome of trauma center need was defined as Injury Severity Score (ISS) greater than 15, intensive care unit admission, urgent operation, or emergency department death. Geriatric (age > 65 years) and adult (age, 16-65 years) cohorts were compared. Triage characteristics and area under the curve (AUC) were compared between SBP of less than 110 mm Hg and SBP of less than 90 mm Hg. Hierarchical logistic regression was used to determine whether geriatric patients newly triaged positive under this change (SBP, 90-109 mm Hg) have a risk of mortality similar to those triaged positive with SBP of less than 90 mm Hg. There were 1,555,944 subjects included. SBP of less than 110 mm Hg had higher sensitivity but lower specificity in geriatric (13% vs. 5%, 93% vs. 99%) and adult (23% vs. 10%, 90% vs. 98%) cohorts. AUC was higher for SBP of less than 110 mm Hg individually in both geriatric and adult (p < 0.01) cohorts. Within the NTTP, the AUC was similar for SBP of less than 110 mm Hg and SBP of less than 90 mm Hg in geriatric subjects but was higher for SBP of less than 90 mm Hg in adult subjects (p < 0.01). Substituting SBP of less than 110 mm Hg resulted in an undertriage reduction of 4.4% with overtriage increase of 4.3% in the geriatric cohort. Geriatric subjects with SBP of 90 mm Hg to 109 mm Hg had an odds of mortality similar to those of geriatric patients with SBP of less than 90 mm Hg (adjusted odds ratio, 1.03; 95% confidence interval, 0.88-1.20; p = 0.71). SBP of less than 110 mm Hg increases sensitivity. SBP of less than 110 mm Hg has discrimination as good as that of SBP of less than 90 mm Hg, with superior improvements in undertriage relative to overtriage in geriatric patients. Geriatric patients newly triaged to be positive under this change have a risk of mortality similar to those under the current SBP criterion. This change in SBP criteria may be merited in geriatric patients, warranting further study to consider elevation to a Step 1 criterion in the NTTP. Diagnostic study, level IV.
Bour, Robert K.; Pozniak, Myron; Ranallo, Frank N.
2015-01-01
The purpose of this paper is to describe our experience with the AAPM Medical Physics Practice Guideline 1.a: “CT Protocol Management and Review Practice Guideline”. Specifically, we will share how our institution's quality management system addresses the suggestions within the AAPM practice report. We feel this paper is needed as it was beyond the scope of the AAPM practice guideline to provide specific details on fulfilling individual guidelines. Our hope is that other institutions will be able to emulate some of our practices and that this article would encourage other types of centers (e.g., community hospitals) to share their methodology for approaching CT protocol optimization and quality control. Our institution had a functioning CT protocol optimization process, albeit informal, since we began using CT. Recently, we made our protocol development and validation process compliant with a number of the ISO 9001:2008 clauses and this required us to formalize the roles of the members of our CT protocol optimization team. We rely heavily on PACS‐based IT solutions for acquiring radiologist feedback on the performance of our CT protocols and the performance of our CT scanners in terms of dose (scanner output) and the function of the automatic tube current modulation. Specific details on our quality management system covering both quality control and ongoing optimization have been provided. The roles of each CT protocol team member have been defined, and the critical role that IT solutions provides for the management of files and the monitoring of CT protocols has been reviewed. In addition, the invaluable role management provides by being a champion for the project has been explained; lack of a project champion will mitigate the efforts of a CT protocol optimization team. Meeting the guidelines set forth in the AAPM practice guideline was not inherently difficult, but did, in our case, require the cooperation of radiologists, technologists, physicists, IT, administrative staff, and hospital management. Some of the IT solutions presented in this paper are novel and currently unique to our institution. PACS number: 87.57.Q PMID:26103176
Gupta, Sandeep Kumar; Trethewey, Scott; Brooker, Bree; Rutherford, Natalie; Diffey, Jenny; Viswanathan, Suresh; Attia, John
2017-01-01
The CT component of SPECT-CT is required for attenuation correction and anatomical localization of the uptake on SPECT but there is no guideline about the optimal CT acquisition parameters. In our department, a standard CT acquisition protocol was changed in 2013 to give lower radiation dose to the patient. In this study, we retrospectively compared the effects on patient dose as well as the CT image quality with current versus older CT protocols. Ninety nine consecutive patients [n=51 Standard dose ‘old’ protocol (SDP); n=48 lower dose ‘new’ protocol (LDP)] with lumbar spine SPECT-CT for bone scan were examined. The main differences between the two protocols were that SDP used 130 kVp tube voltage and reference current-time product of 70 mAs whereas the LDP used 110 kVp and 40 mAs respectively. Various quantitative parameters from the CT images were obtained and the images were also rated blindly by two experienced nuclear medicine physicians for bony definition and noise. The mean calculated dose length product of the LDP group (121.5±39.6 mGy.cm) was significantly lower compared to the SDP group patients (266.9±96.9 mGy.cm; P<0.0001). This translated into a significant reduction in the mean effective dose to 1.8 mSv from 4.0 mSv. The physicians reported better CT image quality for the bony structures in LDP group although for soft tissue structures, the SDP group had better image quality. The optimized new CT acquisition protocol significantly reduced the radiation dose to the patient and in-fact improved CT image quality for the assessment of bony structures. PMID:28533938
Dynamic CT for Parathyroid Adenoma Detection: How Does Radiation Dose Compare With Nuclear Medicine?
Czarnecki, Caroline A; Einsiedel, Paul F; Phal, Pramit M; Miller, Julie A; Lichtenstein, Meir; Stella, Damien L
2018-05-01
Dynamic CT is increasingly used for preoperative localization of parathyroid adenomas, but concerns remain about the radiation effective dose of CT compared with that of 99m Tc-sestamibi scintigraphy. The purpose of this study was to compare the radiation dose delivered by three-phase dynamic CT with that delivered by 99m Tc-sestamibi SPECT/CT performed in accordance with our current protocols and to assess the possible reduction in effective dose achieved by decreasing the scan length (i.e., z-axis) of two phases of the dynamic CT protocol. The effective dose of a 99m Tc-sestamibi nuclear medicine parathyroid study performed with and without coregistration CT was calculated and compared with the effective dose of our current three-phase dynamic CT protocol as well as a proposed protocol involving CT with reduced scan length. The median effective dose for a 99m Tc-sestamibi nuclear medicine study was 5.6 mSv. This increased to 12.4 mSv with the addition of coregistration CT, which is higher than the median effective dose of 9.3 mSv associated with the dynamic CT protocol. Reducing the scan length of two phases in the dynamic CT protocol could reduce the median effective dose to 6.1 mSv, which would be similar to that of the dose from the 99m Tc-sestamibi study alone. Dynamic CT used for the detection of parathyroid adenoma can deliver a lower radiation dose than 99m Tc-sestamibi SPECT/CT. It may be possible to reduce the dose further by decreasing the scan length of two of the phases, although whether this has an impact on accuracy of the localization needs further investigation.
Prosch, Helmut; Schaefer-Prokop, Cornelia M; Eisenhuber, Edith; Kienzl, Daniela; Herold, Christian J
2013-06-01
The aim of this study was to survey the current CT protocols used by members of the European Society of Thoracic Imaging (ESTI) to evaluate patients with interstitial lung diseases (ILD). A questionnaire was e-mailed to 173 ESTI members. The survey focussed on CT acquisition and reconstruction techniques. In particular, questions referred to the use of discontinuous HRCT or volume CT protocols, the acquisition of additional acquisitions in expiration or in the prone position, and methods of radiation dose reduction and on reconstruction algorithms. The overall response rate was 37 %. Eighty-five percent of the respondents used either volume CT alone or in combination with discontinuous HRCT. Forty-five percent of the respondents adapt their CT protocols to the patient's weight and/or age. Expiratory CT or CT in the prone position was performed by 58 % and 59 % of the respondents, respectively. The number of reconstructed series ranged from two to eight. Our survey showed that radiologists with a special interest and experience in chest radiology use a variety of CT protocols for the evaluation of ILD. There is a clear preference for volumetric scans and a strong tendency to use the 3D information. • Experienced thoracic radiologists use various CT protocols for evaluating interstitial lung diseases. • Most workers prefer volumetric CT acquisitions, making use of the 3D information • More attention to reducing the radiation dose appears to be needed.
Albahri, O S; Albahri, A S; Mohammed, K I; Zaidan, A A; Zaidan, B B; Hashim, M; Salman, Omar H
2018-03-22
The new and ground-breaking real-time remote monitoring in triage and priority-based sensor technology used in telemedicine have significantly bounded and dispersed communication components. To examine these technologies and provide researchers with a clear vision of this area, we must first be aware of the utilised approaches and existing limitations in this line of research. To this end, an extensive search was conducted to find articles dealing with (a) telemedicine, (b) triage, (c) priority and (d) sensor; (e) comprehensively review related applications and establish the coherent taxonomy of these articles. ScienceDirect, IEEE Xplore and Web of Science databases were checked for articles on triage and priority-based sensor technology in telemedicine. The retrieved articles were filtered according to the type of telemedicine technology explored. A total of 150 articles were selected and classified into two categories. The first category includes reviews and surveys of triage and priority-based sensor technology in telemedicine. The second category includes articles on the three-tiered architecture of telemedicine. Tier 1 represents the users. Sensors acquire the vital signs of the users and send them to Tier 2, which is the personal gateway that uses local area network protocols or wireless body area network. Medical data are sent from Tier 2 to Tier 3, which is the healthcare provider in medical institutes. Then, the motivation for using triage and priority-based sensor technology in telemedicine, the issues related to the obstruction of its application and the development and utilisation of telemedicine are examined on the basis of the findings presented in the literature.
Suspected leaking abdominal aortic aneurysm: use of sonography in the emergency room.
Shuman, W P; Hastrup, W; Kohler, T R; Nyberg, D A; Wang, K Y; Vincent, L M; Mack, L A
1988-07-01
To determine the value of sonography in the emergent evaluation of suspected leaking abdominal aortic aneurysms, the authors examined 60 patients in the emergency department using sonography and a protocol involving advance radio notification from the ambulance; arrival of sonographic personnel and equipment in the triage room before patient arrival; and, during other triage activities, rapid sonographic evaluation of the aorta for aneurysm and of the paraaortic region for extraluminal blood. Sonographic findings were correlated with surgical results and clinical outcome. When performed under these circumstances, sonography was accurate in demonstrating presence or absence of aneurysm (98%), but its sensitivity for extraluminal blood was poor (4%). A combination of sonographic confirmation of aneurysm, abdominal pain, and unstable hemodynamic condition resulted in the correct decision to perform emergent surgery in 21 of 22 patients (95%). An abbreviated sonographic examination done in the emergency room can provide accurate, useful information about the presence of aneurysm; this procedure does not significantly delay triage of these patients.
Kasparek, Maximilian F; Töpker, Michael; Lazar, Mathias; Weber, Michael; Kasparek, Michael; Mang, Thomas; Apfaltrer, Paul; Kubista, Bernd; Windhager, Reinhard; Ringl, Helmut
2018-06-07
To evaluate the influence of different scan parameters for single-energy CT and dual-energy CT, as well as the impact of different material used in a TKA prosthesis on image quality and the extent of metal artifacts. Eight pairs of TKA prostheses from different vendors were examined in a phantom set-up. Each pair consisted of a conventional CoCr prosthesis and the corresponding anti-allergic prosthesis (full titanium, ceramic, or ceramic-coated) from the same vendor. Nine different (seven dual-energy CT and two single-energy CT) scan protocols with different characteristics were used to determine the most suitable CT protocol for TKA imaging. Quantitative image analysis included assessment of blooming artifacts (metal implants appear thicker on CT than they are, given as virtual growth in mm in this paper) and streak artifacts (thick dark lines around metal). Qualitative image analysis was used to investigate the bone-prosthesis interface. The full titanium prosthesis and full ceramic knee showed significantly fewer blooming artifacts compared to the standard CoCr prosthesis (mean virtual growth 0.6-2.2 mm compared to 2.9-4.6 mm, p < 0.001). Dual-energy CT protocols showed less blooming (range 3.3-3.8 mm) compared to single-energy protocols (4.6-5.5 mm). The full titanium and full ceramic prostheses showed significantly fewer streak artifacts (mean standard deviation 77-86 Hounsfield unit (HU)) compared to the standard CoCr prosthesis (277-334 HU, p < 0.001). All dual-energy CT protocols had fewer metal streak artifacts (215-296 HU compared to single-energy CT protocols (392-497 HU)). Full titanium and ceramic prostheses were ranked superior with regard to the image quality at the bone/prosthesis interface compared to a standard CoCr prosthesis, and all dual-energy CT protocols were ranked better than single-energy protocols. Dual-energy CT and ceramic or titanium prostheses reduce CT artifacts and provide superior image quality of total knee arthroplasty at the bone/prosthesis interface. These findings support the use of dual-energy CT as a solid imaging base for clinical decision-making and the use of full-titanium or ceramic prostheses to allow for better CT visualization of the bone-prosthesis interface.
Wallace, Adam N; Vyhmeister, Ross; Bagade, Swapnil; Chatterjee, Arindam; Hicks, Brandon; Ramirez-Giraldo, Juan Carlos; McKinstry, Robert C
2015-06-01
Cerebrospinal fluid shunts are primarily used for the treatment of hydrocephalus. Shunt complications may necessitate multiple non-contrast head CT scans resulting in potentially high levels of radiation dose starting at an early age. A new head CT protocol using automatic exposure control and automated tube potential selection has been implemented at our institution to reduce radiation exposure. The purpose of this study was to evaluate the reduction in radiation dose achieved by this protocol compared with a protocol with fixed parameters. A retrospective sample of 60 non-contrast head CT scans assessing for cerebrospinal fluid shunt malfunction was identified, 30 of which were performed with each protocol. The radiation doses of the two protocols were compared using the volume CT dose index and dose length product. The diagnostic acceptability and quality of each scan were evaluated by three independent readers. The new protocol lowered the average volume CT dose index from 15.2 to 9.2 mGy representing a 39 % reduction (P < 0.01; 95 % CI 35-44 %) and lowered the dose length product from 259.5 to 151.2 mGy/cm representing a 42 % reduction (P < 0.01; 95 % CI 34-50 %). The new protocol produced diagnostically acceptable scans with comparable image quality to the fixed parameter protocol. A pediatric shunt non-contrast head CT protocol using automatic exposure control and automated tube potential selection reduced patient radiation dose compared with a fixed parameter protocol while producing diagnostic images of comparable quality.
CT protocol management: simplifying the process by using a master protocol concept.
Szczykutowicz, Timothy P; Bour, Robert K; Rubert, Nicholas; Wendt, Gary; Pozniak, Myron; Ranallo, Frank N
2015-07-08
This article explains a method for creating CT protocols for a wide range of patient body sizes and clinical indications, using detailed tube current information from a small set of commonly used protocols. Analytical expressions were created relating CT technical acquisition parameters which can be used to create new CT protocols on a given scanner or customize protocols from one scanner to another. Plots of mA as a function of patient size for specific anatomical regions were generated and used to identify the tube output needs for patients as a function of size for a single master protocol. Tube output data were obtained from the DICOM header of clinical images from our PACS and patient size was measured from CT localizer radiographs under IRB approval. This master protocol was then used to create 11 additional master protocols. The 12 master protocols were further combined to create 39 single and multiphase clinical protocols. Radiologist acceptance rate of exams scanned using the clinical protocols was monitored for 12,857 patients to analyze the effectiveness of the presented protocol management methods using a two-tailed Fisher's exact test. A single routine adult abdominal protocol was used as the master protocol to create 11 additional master abdominal protocols of varying dose and beam energy. Situations in which the maximum tube current would have been exceeded are presented, and the trade-offs between increasing the effective tube output via 1) decreasing pitch, 2) increasing the scan time, or 3) increasing the kV are discussed. Out of 12 master protocols customized across three different scanners, only one had a statistically significant acceptance rate that differed from the scanner it was customized from. The difference, however, was only 1% and was judged to be negligible. All other master protocols differed in acceptance rate insignificantly between scanners. The methodology described in this paper allows a small set of master protocols to be adapted among different clinical indications on a single scanner and among different CT scanners.
2004-10-01
and necrosis using CT, magnetic resonance, thermal imaging, and near-infrared spectroscopy. These have led to numerous publications, patents, products...Willerson, Buja, Litovsky) 13. Project II.D ....................................... 99 Thermal Detection and Treatment of Inflammation and Necrosis ...2002). ,’Endotoxin stress- response in cardiomyocytes: NF-kappaB• activation and tumor necrosis factor-alpha expression," Am J Physiol Heart Circ Physiol
Colins, Olivier F.
2016-01-01
It is unknown if the DSM-oriented (DSM) scales of the Youth Self-Report (YSR) are useful to determine what kind of narrowly-focused psychiatric assessment is needed, and how well these scales serve as a triage tool in real-world forensic settings. To address this knowledge gap, the YSR and diagnostic interviews were administered to 405 detained boys as part of a clinical protocol. Continuous DSM scale scores (e.g., Conduct Problems) were moderately to highly accurate in predicting their corresponding disorder (e.g., conduct disorder), whereas dichotomized DSM scale scores were not. To test the DSM scales’ usefulness for triage purposes, the sensitivity and specificity of being in the borderline range of one or more DSM scales were calculated. Almost all boys who did not have a disorder were in the normal range of at least one DSM scale (high specificity). However, many boys with a disorder would have been missed if such a decision rule was used for triage purposes (low sensitivity). In conclusion, their relations with the corresponding disorders support the construct validity of the DSM scales in an applied forensic setting. Nevertheless, the findings also warrant against the use of these scales for planning further narrowly-focused assessment or for triage purposes. PMID:27657102
Patient doses from CT examinations in Turkey.
Ataç, Gökçe Kaan; Parmaksız, Aydın; İnal, Tolga; Bulur, Emine; Bulgurlu, Figen; Öncü, Tolga; Gündoğdu, Sadi
2015-01-01
We aimed to establish the first diagnostic reference levels (DRLs) for computed tomography (CT) examinations in adult and pediatric patients in Turkey and compare these with international DRLs. CT performance information and examination parameters (for head, chest, high-resolution CT of the chest [HRCT-chest], abdominal, and pelvic protocols) from 1607 hospitals were collected via a survey. Dose length products and effective doses for standard patient sizes were calculated from the reported volume CT dose index (CTDIvol). The median number of protocols reported from the 167 responding hospitals (10% response rate) was 102 across five different age groups. Third quartile CTDIvol values for adult pelvic and all pediatric body protocols were higher than the European Commission standards but were comparable to studies conducted in other countries. The radiation dose indicators for adult patients were similar to those reported in the literature, except for those associated with head protocols. CT protocol optimization is necessary for adult head and pediatric chest, HRCT-chest, abdominal, and pelvic protocols. The findings from this study are recommended for use as national DRLs in Turkey.
Methods for CT automatic exposure control protocol translation between scanner platforms.
McKenney, Sarah E; Seibert, J Anthony; Lamba, Ramit; Boone, John M
2014-03-01
An imaging facility with a diverse fleet of CT scanners faces considerable challenges when propagating CT protocols with consistent image quality and patient dose across scanner makes and models. Although some protocol parameters can comfortably remain constant among scanners (eg, tube voltage, gantry rotation time), the automatic exposure control (AEC) parameter, which selects the overall mA level during tube current modulation, is difficult to match among scanners, especially from different CT manufacturers. Objective methods for converting tube current modulation protocols among CT scanners were developed. Three CT scanners were investigated, a GE LightSpeed 16 scanner, a GE VCT scanner, and a Siemens Definition AS+ scanner. Translation of the AEC parameters such as noise index and quality reference mAs across CT scanners was specifically investigated. A variable-diameter poly(methyl methacrylate) phantom was imaged on the 3 scanners using a range of AEC parameters for each scanner. The phantom consisted of 5 cylindrical sections with diameters of 13, 16, 20, 25, and 32 cm. The protocol translation scheme was based on matching either the volumetric CT dose index or image noise (in Hounsfield units) between two different CT scanners. A series of analytic fit functions, corresponding to different patient sizes (phantom diameters), were developed from the measured CT data. These functions relate the AEC metric of the reference scanner, the GE LightSpeed 16 in this case, to the AEC metric of a secondary scanner. When translating protocols between different models of CT scanners (from the GE LightSpeed 16 reference scanner to the GE VCT system), the translation functions were linear. However, a power-law function was necessary to convert the AEC functions of the GE LightSpeed 16 reference scanner to the Siemens Definition AS+ secondary scanner, because of differences in the AEC functionality designed by these two companies. Protocol translation on the basis of quantitative metrics (volumetric CT dose index or measured image noise) is feasible. Protocol translation has a dependency on patient size, especially between the GE and Siemens systems. Translation schemes that preserve dose levels may not produce identical image quality. Copyright © 2014 American College of Radiology. Published by Elsevier Inc. All rights reserved.
Multilocation teleradiology system for emergency triage consultation
NASA Astrophysics Data System (ADS)
Herron, John M.; Yonas, Howard
1996-05-01
A remote consultation system is available at the University of Pittsburgh Medical Center (UPMC) which links four outlying hospitals in Western Pennsylvania and Eastern Ohio. This system has the potential to improve short and long term clinical outcomes and to reduce overall medical care cost by establishing improved emergency triage capability. An EMED, Inc. teleradiology system permits rapid, high-quality transfer of digitized film and CT images from the remote sites to the tertiary care center (UPMC). The images are sent over dial-on- demand ISDN and SW56 lines from the remote hospitals to a central server where they are transmitted to a dual 2K monitor workstation in the Emergency Department, thirteen Eastman Kodak PDS workstations within UPMC, and to three physician homes. Transmission to a workstation at each of the physician homes over ISDN lines enables `after hours' consultation. The radiographic images along with voice and fax communications provide a technique where physicians in outlying hospitals will be able to consult with specialists at any time. A study is in progress to evaluate the effectiveness of this system in terms of perception of utility and its potential to improve emergency triage capability, as well as selection of the appropriate transportation mode (helicopter versus ambulance).
NASA Astrophysics Data System (ADS)
McDougald, Wendy A.; Collins, Richard; Green, Mark; Tavares, Adriana A. S.
2017-10-01
Obtaining accurate quantitative measurements in preclinical Positron Emission Tomography/Computed Tomography (PET/CT) imaging is of paramount importance in biomedical research and helps supporting efficient translation of preclinical results to the clinic. The purpose of this study was two-fold: (1) to investigate the effects of different CT acquisition protocols on PET/CT image quality and data quantification; and (2) to evaluate the absorbed dose associated with varying CT parameters. Methods: An air/water quality control CT phantom, tissue equivalent material phantom, an in-house 3D printed phantom and an image quality PET/CT phantom were imaged using a Mediso nanoPET/CT scanner. Collected data was analyzed using PMOD software, VivoQuant software and National Electric Manufactures Association (NEMA) software implemented by Mediso. Measured Hounsfield Unit (HU) in collected CT images were compared to the known HU values and image noise was quantified. PET recovery coefficients (RC), uniformity and quantitative bias were also measured. Results: Only less than 2% and 1% of CT acquisition protocols yielded water HU values < -80 and air HU values < -840, respectively. Four out of eleven CT protocols resulted in more than 100 mGy absorbed dose. Different CT protocols did not impact PET uniformity and RC, and resulted in <4% overall bias relative to expected radioactive concentration. Conclusion: Preclinical CT protocols with increased exposure times can result in high absorbed doses to the small animals. These should be avoided, as they do not contributed towards improved microPET/CT image quantitative accuracy and could limit longitudinal scanning of small animals.
Yang, Ching-Ching; Yang, Bang-Hung; Tu, Chun-Yuan; Wu, Tung-Hsin; Liu, Shu-Hsin
2017-06-01
This study aimed to evaluate the efficacy of automatic exposure control (AEC) in order to optimize low-dose computed tomography (CT) protocols for patients of different ages undergoing cardiac PET/CT and single-photon emission computed tomography/computed tomography (SPECT/CT). One PET/CT and one SPECT/CT were used to acquire CT images for four anthropomorphic phantoms representative of 1-year-old, 5-year-old and 10-year-old children and an adult. For the hybrid systems investigated in this study, the radiation dose and image quality of cardiac CT scans performed with AEC activated depend mainly on the selection of a predefined image quality index. Multiple linear regression methods were used to analyse image data from anthropomorphic phantom studies to investigate the effects of body size and predefined image quality index on CT radiation dose in cardiac PET/CT and SPECT/CT scans. The regression relationships have a coefficient of determination larger than 0.9, indicating a good fit to the data. According to the regression models, low-dose protocols using the AEC technique were optimized for patients of different ages. In comparison with the standard protocol with AEC activated for adult cardiac examinations used in our clinical routine practice, the optimized paediatric protocols in PET/CT allow 32.2, 63.7 and 79.2% CT dose reductions for anthropomorphic phantoms simulating 10-year-old, 5-year-old and 1-year-old children, respectively. The corresponding results for cardiac SPECT/CT are 8.4, 51.5 and 72.7%. AEC is a practical way to reduce CT radiation dose in cardiac PET/CT and SPECT/CT, but the AEC settings should be determined properly for optimal effect. Our results show that AEC does not eliminate the need for paediatric protocols and CT examinations using the AEC technique should be optimized for paediatric patients to reduce the radiation dose as low as reasonably achievable.
Automatic CT simulation optimization for radiation therapy: A general strategy.
Li, Hua; Yu, Lifeng; Anastasio, Mark A; Chen, Hsin-Chen; Tan, Jun; Gay, Hiram; Michalski, Jeff M; Low, Daniel A; Mutic, Sasa
2014-03-01
In radiation therapy, x-ray computed tomography (CT) simulation protocol specifications should be driven by the treatment planning requirements in lieu of duplicating diagnostic CT screening protocols. The purpose of this study was to develop a general strategy that allows for automatically, prospectively, and objectively determining the optimal patient-specific CT simulation protocols based on radiation-therapy goals, namely, maintenance of contouring quality and integrity while minimizing patient CT simulation dose. The authors proposed a general prediction strategy that provides automatic optimal CT simulation protocol selection as a function of patient size and treatment planning task. The optimal protocol is the one that delivers the minimum dose required to provide a CT simulation scan that yields accurate contours. Accurate treatment plans depend on accurate contours in order to conform the dose to actual tumor and normal organ positions. An image quality index, defined to characterize how simulation scan quality affects contour delineation, was developed and used to benchmark the contouring accuracy and treatment plan quality within the predication strategy. A clinical workflow was developed to select the optimal CT simulation protocols incorporating patient size, target delineation, and radiation dose efficiency. An experimental study using an anthropomorphic pelvis phantom with added-bolus layers was used to demonstrate how the proposed prediction strategy could be implemented and how the optimal CT simulation protocols could be selected for prostate cancer patients based on patient size and treatment planning task. Clinical IMRT prostate treatment plans for seven CT scans with varied image quality indices were separately optimized and compared to verify the trace of target and organ dosimetry coverage. Based on the phantom study, the optimal image quality index for accurate manual prostate contouring was 4.4. The optimal tube potentials for patient sizes of 38, 43, 48, 53, and 58 cm were 120, 140, 140, 140, and 140 kVp, respectively, and the corresponding minimum CTDIvol for achieving the optimal image quality index 4.4 were 9.8, 32.2, 100.9, 241.4, and 274.1 mGy, respectively. For patients with lateral sizes of 43-58 cm, 120-kVp scan protocols yielded up to 165% greater radiation dose relative to 140-kVp protocols, and 140-kVp protocols always yielded a greater image quality index compared to the same dose-level 120-kVp protocols. The trace of target and organ dosimetry coverage and the γ passing rates of seven IMRT dose distribution pairs indicated the feasibility of the proposed image quality index for the predication strategy. A general strategy to predict the optimal CT simulation protocols in a flexible and quantitative way was developed that takes into account patient size, treatment planning task, and radiation dose. The experimental study indicated that the optimal CT simulation protocol and the corresponding radiation dose varied significantly for different patient sizes, contouring accuracy, and radiation treatment planning tasks.
Outpatient desensitization in selected patients with platinum hypersensitivity reactions.
O'Malley, David M; Vetter, Monica Hagan; Cohn, David E; Khan, Ambar; Hays, John L
2017-06-01
Platinum-based chemotherapies are a standard treatment for both initial and recurrent gynecologic cancers. Given this widespread use, it is important to be aware of the features of platinum hypersensitivity reactions and the subsequent treatment of these reactions. There is also increasing interest in the development of desensitization protocols to allow patients with a history of platinum hypersensitivity to receive further platinum based therapy. In this review, we describe the management of platinum hypersensitivity reactions and the desensitization protocols utilized at our institution. We also describe the clinical categorizations utilized to triage patients to appropriate desensitization protocols. Copyright © 2017 Elsevier Inc. All rights reserved.
Cleary, N; McNulty, J P; Foley, S J; Kelly, E
2017-11-01
Iodinated contrast extravasation is a serious complication associated with intravenous administration in radiology. Departmental protocols and the radiographer's approach on both prevention techniques and treatment will affect the prevalence of extravasation, and the eventual outcome for the patient when it does occur. To examine contrast extravasation protocols in place in Irish CT departments for alignment with European Society of Urogenital Radiology (ESUR) Guidelines (2014); to establish radiographer's opinions on contrast extravasation; and to examine radiographer adherence to protocols. Contrast extravasation protocols from a purposively selected sample of CT departments across Ireland (n = 6) were compared to ESUR guidelines, followed by an online survey of CT radiographers practicing in the participating centres. All participating CT departments (n = 5) had written protocols in place. High risk patients, such as elderly or unconscious, were identified in most protocols, however, children were mentioned in just one protocol and obese patients were not specified in any. The response rate of CT radiographers was 23% (n = 24). 58% (n = 14) of respondents indicated that contrast extravasation was more likely during CTA examinations. While high levels of confidence in managing extravasation were reported, suggested treatment approaches, and confidence in same, was more variable. Clinical workload in CT departments was also identified as a factor impacting on patient care and management. While contrast extravasation protocols were generally in line with ESUR Guidelines, high risk patients may not be getting sufficient attention. More radiographer awareness of patient monitoring needs, particularly in busy departments with a heavy workload may also reduce extravasation risk, and improve management of same. Copyright © 2017 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.
CT protocol management: simplifying the process by using a master protocol concept
Bour, Robert K.; Rubert, Nicholas; Wendt, Gary; Pozniak, Myron; Ranallo, Frank N.
2015-01-01
This article explains a method for creating CT protocols for a wide range of patient body sizes and clinical indications, using detailed tube current information from a small set of commonly used protocols. Analytical expressions were created relating CT technical acquisition parameters which can be used to create new CT protocols on a given scanner or customize protocols from one scanner to another. Plots of mA as a function of patient size for specific anatomical regions were generated and used to identify the tube output needs for patients as a function of size for a single master protocol. Tube output data were obtained from the DICOM header of clinical images from our PACS and patient size was measured from CT localizer radiographs under IRB approval. This master protocol was then used to create 11 additional master protocols. The 12 master protocols were further combined to create 39 single and multiphase clinical protocols. Radiologist acceptance rate of exams scanned using the clinical protocols was monitored for 12,857 patients to analyze the effectiveness of the presented protocol management methods using a two‐tailed Fisher's exact test. A single routine adult abdominal protocol was used as the master protocol to create 11 additional master abdominal protocols of varying dose and beam energy. Situations in which the maximum tube current would have been exceeded are presented, and the trade‐offs between increasing the effective tube output via 1) decreasing pitch, 2) increasing the scan time, or 3) increasing the kV are discussed. Out of 12 master protocols customized across three different scanners, only one had a statistically significant acceptance rate that differed from the scanner it was customized from. The difference, however, was only 1% and was judged to be negligible. All other master protocols differed in acceptance rate insignificantly between scanners. The methodology described in this paper allows a small set of master protocols to be adapted among different clinical indications on a single scanner and among different CT scanners. PACS number: 87.57.Q PMID:26219005
Kusk, Martin Weber; Karstoft, Jens; Mussmann, Bo Redder
2015-11-01
Generation of multiplanar reformation (MPR) images has become automatic on most modern computed tomography (CT) scanners, potentially increasing the workload of the reporting radiologists. It is not always clear if this increases diagnostic performance in all clinical tasks. To assess detection performance using only coronal multiplanar reformations (MPR) when triaging patients for lung malignancies with CT compared to images in three orthogonal planes, and to evaluate performance comparison of novice and experienced readers. Retrospective study of 63 patients with suspicion of lung cancer, scanned on 64-slice multidetector computed tomography (MDCT) with images reconstructed in three planes. Coronal images were presented to four readers, two novice and two experienced. Readers decided whether the patients were suspicious for malignant disease, and indicated their confidence on a five-point scale. Sensitivity and specificity on per-patient basis was calculated with regards to a reference standard of histological diagnosis, and compared with the original report using McNemar's test. Receiver operating characteristic (ROC) curves were plotted to compare the performance of the four readers, using the area under the curve (AUC) as figure of merit. No statistically significant difference of sensitivity and specificity was found for any of the readers when compared to the original reports. ROC analysis yielded AUCs in the range of 0.92-0.93 for all readers with no significant difference. Inter-rater agreement was substantial (kappa = 0.72). Sensitivity and specificity were comparable to diagnosis using images in three planes. No significant difference was found between experienced and novice readers. © The Foundation Acta Radiologica 2014.
Advances in cardiac CT contrast injection and acquisition protocols.
Scholtz, Jan-Erik; Ghoshhajra, Brian
2017-10-01
Cardiac computed tomography (CT) imaging has become an important part of modern cardiovascular care. Coronary CT angiography (CTA) is the first choice imaging modality for non-invasive visualization of coronary artery stenosis. In addition, cardiac CT does not only provide anatomical evaluation, but also functional and valvular assessment, and myocardial perfusion evaluation. In this article we outline the factors which influence contrast enhancement, give an overview of current contrast injection and acquisition protocols, with focus on current emerging topics such as pre-transcatheter aortic valve replacement (TAVR) planning, cardiac CT for congenital heart disease (CHD) patients, and myocardial CT perfusion (CTP). Further, we point out areas where we see potential for future improvements in cardiac CT imaging based on a closer interaction between CT scanner settings and contrast injection protocols to tailor injections to patient- and exam-specific factors.
Advances in cardiac CT contrast injection and acquisition protocols
Scholtz, Jan-Erik
2017-01-01
Cardiac computed tomography (CT) imaging has become an important part of modern cardiovascular care. Coronary CT angiography (CTA) is the first choice imaging modality for non-invasive visualization of coronary artery stenosis. In addition, cardiac CT does not only provide anatomical evaluation, but also functional and valvular assessment, and myocardial perfusion evaluation. In this article we outline the factors which influence contrast enhancement, give an overview of current contrast injection and acquisition protocols, with focus on current emerging topics such as pre-transcatheter aortic valve replacement (TAVR) planning, cardiac CT for congenital heart disease (CHD) patients, and myocardial CT perfusion (CTP). Further, we point out areas where we see potential for future improvements in cardiac CT imaging based on a closer interaction between CT scanner settings and contrast injection protocols to tailor injections to patient- and exam-specific factors. PMID:29255688
Scott, Greg; Clawson, Jeff; Fivaz, Mark C; McQueen, Jennie; Gardett, Marie I; Schultz, Bryon; Youngquist, Scott; Olola, Christopher H O
2016-02-01
Using the Medical Priority Dispatch System (MPDS) - a systematic 911 triage process - to identify a large subset of low-acuity patients for secondary nurse triage in the 911 center is a largely unstudied practice in North America. This study examines the ALPHA-level subset of low-acuity patients in the MPDS to determine the suitability of these patients for secondary triage by evaluating vital signs and necessity of lights-and-siren transport, as determined by attending Emergency Medical Services (EMS) ambulance crews. The primary objective of this study was to determine the clinical status of MPDS ALPHA-level (low-acuity) patients, as determined by on-scene EMS crews' patient care records, in two US agencies. A secondary objective was to determine which ALPHA-level codes are suitable candidates for secondary triage by a trained Emergency Communication Nurse (ECN). In this retrospective study, one full year (2013) of both dispatch data and EMS patient records data, associated with all calls coded at the ALPHA-level (low-acuity) in the dispatch protocol, were collected. The primary outcome measure was the number and percentage of ALPHA-level codes categorized as low-acuity, moderate-acuity, high-acuity, and critical using four common vital signs to assign these categories: systolic blood pressure (SBP), pulse rate (PR), oxygen saturation (SpO2), and Glasgow Coma Score (GCS). Vital sign data were obtained from ambulance crew electronic patient care records (ePCRs). The secondary endpoint was the number and percentage of ALPHA-level codes that received a "hot" (lights-and-siren) transport. Out of 19,300 cases, 16,763 (86.9%) were included in the final analysis, after excluding cases from health care providers and those with missing data. Of those, 89% of all cases did not have even one vital sign indicator of unstable patient status (high or critical vital sign). Of all cases, only 1.1% were transported lights-and-siren. With the exception of the low-acuity, ALPHA-level seizure cases, the ALPHA-level patients are suitable to transfer for secondary triage in a best-practices, accredited, emergency medical dispatch center that utilizes the MPDS at very high compliance rates. The secondary nurse triage process should identify the few at-risk patients that exist in the low-acuity calls.
Thomas, C; Patschan, O; Ketelsen, D; Tsiflikas, I; Reimann, A; Brodoefel, H; Buchgeister, M; Nagele, U; Stenzl, A; Claussen, C; Kopp, A; Heuschmid, M; Schlemmer, H-P
2009-06-01
The efficiency and radiation dose of a low-dose dual-energy (DE) CT protocol for the evaluation of urinary calculus disease were evaluated. A low-dose dual-source DE-CT renal calculi protocol (140 kV, 46 mAs; 80 kV, 210 mAs) was derived from the single-energy (SE) CT protocol used in our institution for the detection of renal calculi (120 kV, 75 mAs). An Alderson-Rando phantom was equipped with thermoluminescence dosimeters and examined by CT with both protocols. The effective doses were calculated. Fifty-one patients with suspected or known urinary calculus disease underwent DE-CT. DE analysis was performed if calculi were detected using a dedicated software tool. Results were compared to chemical analysis after invasive calculus extraction. An effective dose of 3.43 mSv (male) and 5.30 mSv (female) was measured in the phantom for the DE protocol (vs. 3.17/4.57 mSv for the SE protocol). Urinary calculi were found in 34 patients; in 28 patients, calculi were removed and analyzed (23 patients with calcified calculi, three with uric acid calculi, one with 2,8-dihyxdroxyadenine-calculi, one patient with a mixed struvite calculus). DE analysis was able to distinguish between calcified and non-calcified calculi in all cases. In conclusion, dual-energy urinary calculus analysis is effective also with a low-dose protocol. The protocol tested in this study reliably identified calcified urinary calculi in vivo.
Sun, Z; Al Ghamdi, KS; Baroum, IH
2012-01-01
Purpose: To investigate whether the multislice CT scanning protocols of head, chest and abdomen are adjusted according to patient’s age in paediatric patients. Materials and Methods: Multislice CT examination records of paediatric patients undergoing head, chest and abdomen scans from three public hospitals during a one-year period were retrospectively reviewed. Patients were categorised into the following age groups: under 4 years, 5–8 years, 9–12 years and 13–16 years, while the tube current was classified into the following ranges: < 49 mA, 50–99 mA, 100–149 mA, 150–199 mA, > 200 mA and unknown. Results: A total of 4998 patient records, comprising a combination of head, chest and abdomen CT scans, were assessed, with head CT scans representing nearly half of the total scans. Age-based adjusted CT protocols were observed in most of the scans with higher tube current setting being used with increasing age. However, a high tube current (150–199 mA) was still used in younger patients (0–8 years) undergoing head CT scans. In one hospital, CT protocols remained constant across all age groups, indicating potential overexposure to the patients. Conclusion: This analysis shows that paediatric CT scans are adjusted according to the patient’s age in most of the routine CT examinations. This indicates increased awareness regarding radiation risks associated with CT. However, high tube current settings are still used in younger patient groups, thus, optimisation of paediatric CT protocols and implementation of current guidelines, such as age-and weight-based scanning, should be recommended in daily practice. PMID:22970059
Research on a Queue Scheduling Algorithm in Wireless Communications Network
NASA Astrophysics Data System (ADS)
Yang, Wenchuan; Hu, Yuanmei; Zhou, Qiancai
This paper proposes a protocol QS-CT, Queue Scheduling Mechanism based on Multiple Access in Ad hoc net work, which adds queue scheduling mechanism to RTS-CTS-DATA using multiple access protocol. By endowing different queues different scheduling mechanisms, it makes networks access to the channel much more fairly and effectively, and greatly enhances the performance. In order to observe the final performance of the network with QS-CT protocol, we simulate it and compare it with MACA/C-T without QS-CT protocol. Contrast to MACA/C-T, the simulation result shows that QS-CT has greatly improved the throughput, delay, rate of packets' loss and other key indicators.
Dantas, Roberto Nery; Assuncao, Antonildes Nascimento; Marques, Ismar Aguiar; Fahel, Mateus Guimaraes; Nomura, Cesar Higa; Avila, Luiz Francisco Rodrigues; Giorgi, Maria Clementina Pinto; Soares, Jose; Meneghetti, Jose Claudio; Parga, Jose Rodrigues
2018-06-01
Despite advances in non-invasive myocardial perfusion imaging (MPI) evaluation, computed tomography (CT) multiphase MPI protocols have not yet been compared with the highly accurate rubidium-82 positron emission tomography ( 82 RbPET) MPI. Thus, this study aimed to evaluate agreement between 82 RbPET and 320-detector row CT (320-CT) MPI using a multiphase protocol in suspected CAD patients. Forty-four patients referred for MPI evaluation were prospectively enrolled and underwent dipyridamole stress 82 RbPET and multiphase 320-CT MPI (five consecutive volumetric acquisitions during stress). Statistical analyses were performed using the R software. There was high agreement for recognizing summed stress scores ≥ 4 (kappa 0.77, 95% CI 0.55-0.98, p < 0.001) and moderate for detecting SDS ≥ 2 (kappa 0.51, 95% CI 0.23-0.80, p < 0.001). In a per segment analysis, agreement was high for the presence of perfusion defects during stress and rest (kappa 0.75 and 0.82, respectively) and was moderate for impairment severity (kappa 0.58 and 0.65, respectively). The 320-CT protocol was safe, with low radiation burden (9.3 ± 2.4 mSv). There was a significant agreement between dipyridamole stress 320-CT MPI and 82 RbPET MPI in the evaluation of suspected CAD patients of intermediate risk. The multiphase 320-CT MPI protocol was feasible, diagnostic and with relatively low radiation exposure. • Rubidium-82 PET and 320-MDCT can perform MPI studies for CAD investigation. • There is high agreement between rubidium-82 PET and 320-MDCT for MPI assessment. • Multiphase CT perfusion protocols are feasible and with low radiation. • Multiphase CT perfusion protocols can identify image artefacts.
Gaudio, Carlo; Petriello, Gennaro; Pelliccia, Francesco; Tanzilli, Alessandra; Bandiera, Alberto; Tanzilli, Gaetano; Barillà, Francesco; Paravati, Vincenzo; Pellegrini, Massimo; Mangieri, Enrico; Barillari, Paolo
2018-05-08
Cardiac computed tomography (CT) is often performed in patients who are at high risk for lung cancer in whom screening is currently recommended. We tested diagnostic ability and radiation exposure of a novel ultra-low-dose CT protocol that allows concomitant coronary artery evaluation and lung screening. We studied 30 current or former heavy smoker subjects with suspected or known coronary artery disease who underwent CT assessment of both coronary arteries and thoracic area (Revolution CT, General Electric). A new ultrafast-low-dose single protocol was used for ECG-gated helical acquisition of the heart and the whole chest. A single IV iodine bolus (70-90 ml) was used. All patients with CT evidence of coronary stenosis underwent also invasive coronary angiography. All the coronary segments were assessable in 28/30 (93%) patients. Only 8 coronary segments were not assessable in 2 patients due to motion artefacts (assessability: 98%; 477/485 segments). In the assessable segments, 20/21 significant stenoses (> 70% reduction of vessel diameter) were correctly diagnosed. Pulmonary nodules were detected in 5 patients, thus requiring to schedule follow-up surveillance CT thorax. Effective dose was 1.3 ± 0.9 mSv (range: 0.8-3.2 mSv). Noteworthy, no contrast or radiation dose increment was required with the new protocol as compared to conventional coronary CT protocol. The novel ultrafast-low-dose CT protocol allows lung cancer screening at time of coronary artery evaluation. The new approach might enhance the cost-effectiveness of coronary CT in heavy smokers with suspected or known coronary artery disease.
Yoshida, Morikatsu; Utsunomiya, Daisuke; Kidoh, Masafumi; Yuki, Hideaki; Oda, Seitaro; Shiraishi, Shinya; Yamamoto, Hidekazu; Inomata, Yukihiro; Yamashita, Yasuyuki
2017-06-01
We evaluated whether donor computed tomography (CT) with a combined technique of lower tube voltage and iterative reconstruction (IR) can provide sufficient preoperative information for liver transplantation.We retrospectively reviewed CT of 113 liver donor candidates. Dynamic contrast-enhanced CT of the liver was performed on the following protocol: protocol A (n = 70), 120-kVp with filtered back projection (FBP); protocol B (n = 43), 100-kVp with IR. To equalize the background covariates, one-to-one propensity-matched analysis was used. We visually compared the score of the hepatic artery (A-score), portal vein (P-score), and hepatic vein (V-score) of the 2 protocols and quantitatively correlated the graft volume obtained by CT volumetry (graft-CTv) under the 2 protocols with the actual graft weight.In total, 39 protocol-A and protocol-B candidates showed comparable preoperative clinical characteristics with propensity matching. For protocols A and B, the A-score was 3.87 ± 0.73 and 4.51 ± 0.56 (P < .01), the P-score was 4.92 ± 0.27 and 5.0 ± 0.0 (P = .07), and the V-score was 4.23 ± 0.78 and 4.82 ± 0.39 (P < .01), respectively. Correlations between the actual graft weight and graft-CTv of protocols A and B were 0.97 and 0.96, respectively.Liver-donor CT imaging under 100-kVp plus IR protocol provides better visualization for vascular structures than that under 120-kVp plus FBP protocol with comparable accuracy for graft-CTv, while lowering radiation exposure by more than 40% and reducing contrast-medium dose by 20%.
Lee, Kyung Hee; Lee, Kyung Won; Park, Ji Hoon; Han, Kyunghwa; Kim, Jihang; Lee, Sang Min; Park, Chang Min
2018-01-01
To measure inter-protocol agreement and analyze interchangeability on nodule classification between low-dose unenhanced CT and standard-dose enhanced CT. From nodule libraries containing both low-dose unenhanced and standard-dose enhanced CT, 80 solid and 80 subsolid (40 part-solid, 40 non-solid) nodules of 135 patients were selected. Five thoracic radiologists categorized each nodule into solid, part-solid or non-solid. Inter-protocol agreement between low-dose unenhanced and standard-dose enhanced images was measured by pooling κ values for classification into two (solid, subsolid) and three (solid, part-solid, non-solid) categories. Interchangeability between low-dose unenhanced and standard-dose enhanced CT for the classification into two categories was assessed using a pre-defined equivalence limit of 8 percent. Inter-protocol agreement for the classification into two categories {κ, 0.96 (95% confidence interval [CI], 0.94-0.98)} and that into three categories (κ, 0.88 [95% CI, 0.85-0.92]) was considerably high. The probability of agreement between readers with standard-dose enhanced CT was 95.6% (95% CI, 94.5-96.6%), and that between low-dose unenhanced and standard-dose enhanced CT was 95.4% (95% CI, 94.7-96.0%). The difference between the two proportions was 0.25% (95% CI, -0.85-1.5%), wherein the upper bound CI was markedly below 8 percent. Inter-protocol agreement for nodule classification was considerably high. Low-dose unenhanced CT can be used interchangeably with standard-dose enhanced CT for nodule classification.
NASA Astrophysics Data System (ADS)
Strocchi, Sabina; Colli, Vittoria; Novario, Raffaele; Carrafiello, Gianpaolo; Giorgianni, Andrea; Macchi, Aldo; Fugazzola, Carlo; Conte, Leopoldo
2007-03-01
Aim of this work is to compare the performances of a Xoran Technologies i-CAT Cone Beam CT for dental applications with those of a standard total body multislice CT (Toshiba Aquilion 64 multislice) used for dental examinations. Image quality and doses to patients have been compared for the three main i-CAT protocols, the Toshiba standard protocol and a Toshiba modified protocol. Images of two phantoms have been acquired: a standard CT quality control phantom and an Alderson Rando ® anthropomorphic phantom. Image noise, Signal to Noise Ratio (SNR), Contrast to Noise Ratio (CNR) and geometric accuracy have been considered. Clinical image quality was assessed. Effective dose and doses to main head and neck organs were evaluated by means of thermo-luminescent dosimeters (TLD-100) placed in the anthropomorphic phantom. A Quality Index (QI), defined as the ratio of squared CNR to effective dose, has been evaluated. The evaluated effective doses range from 0.06 mSv (i-CAT 10 s protocol) to 2.37 mSv (Toshiba standard protocol). The Toshiba modified protocol (halved tube current, higher pitch value) imparts lower effective dose (0.99 mSv). The conventional CT device provides lower image noise and better SNR, but clinical effectiveness similar to that of dedicated dental CT (comparable CNR and clinical judgment). Consequently, QI values are much higher for this second CT scanner. No geometric distortion has been observed with both devices. As a conclusion, dental volumetric CT supplies adequate image quality to clinical purposes, at doses that are really lower than those imparted by a conventional CT device.
Comprehensive CT Evaluation in Acute Ischemic Stroke: Impact on Diagnosis and Treatment Decisions
Löve, Askell; Siemund, Roger; Andsberg, Gunnar; Cronqvist, Mats; Holtås, Stig; Björkman-Burtscher, Isabella
2011-01-01
Background. With modern CT imaging a comprehensive overview of cerebral macro- and microcirculation can be obtained within minutes in acute ischemic stroke. This opens for patient stratification and individualized treatment. Methods. Four patients with acute ischemic stroke of different aetiologies and/or treatments were chosen for illustration of the comprehensive CT protocol and its value in subsequent treatment decisions. The patients were clinically evaluated according to the NIHSS-scale, examined with the comprehensive CT protocol including both CT angiography and CT perfusion, and followed up by MRI. Results. The comprehensive CT examination protocol increased the examination time but did not delay treatment initiation. In some cases CT angiography revealed the cause of stroke while CT perfusion located and graded the perfusion defect with reasonable accuracy, confirmed by follow-up MR-diffusion. In the presented cases findings of the comprehensive CT examination influenced the treatment strategy. Conclusions. The comprehensive CT examination is a fast and safe method allowing accurate diagnosis and making way for individualized treatment in acute ischemic stroke. PMID:21603175
Chowdhury, Sharfuddin; Nicol, Andrew John; Moydien, Mahammed Riyaad; Navsaria, Pradeep Harkison; Montoya-Pelaez, Luis Felipe
2018-01-01
The optimal timing for emergency surgical interventions and implementation of protocols for trauma surgery is insufficient in the literature. The Groote Schuur emergency surgery triage (GSEST) system, based on Cape Triaging Score (CTS), is followed at Groote Schuur Hospital (GSH) for triaging emergency surgical cases including trauma cases. The study aimed to look at the effect of delay in surgery after scheduling based on the GSEST system has an impact on outcome in terms of postoperative complications and death. Prospective audit of patients presenting to GSH trauma center following penetrating or blunt chest, abdominal, neck and peripheral vascular trauma who underwent surgery over a 4-month period was performed. Post-operative complications were graded according to Clavien-Dindo classification of surgical complications. One-hundred six patients underwent surgery during the study period. One-hundred two (96.2%) cases were related to penetrating trauma. Stab wounds comprised 71 (67%) and gunshot wounds (GSW) 31 (29.2%) cases. Of the 106 cases, 6, 47, 40, and 13 patients were booked as red, orange, yellow, and green, respectively. The median delay for green, yellow, and orange cases was within the expected time. The red patients took unexpectedly longer (median delay 48 min, IQR 35-60 min). Thirty-one (29.3%) patients developed postoperative complications. Among the booked red, orange, yellow, and green cases, postoperative complications developed in 3, 18, 9, and 1 cases, respectively. Only two (1.9%) postoperative deaths were documented during the study period. There was no statistically significant association between operative triage and post-operative complications ( p = 0.074). Surgical case categorization has been shown to be useful in prioritizing emergency trauma surgical cases in a resource constraint high-volume trauma center.
Herts, Brian R; Baker, Mark E; Obuchowski, Nancy; Primak, Andrew; Schneider, Erika; Rhana, Harpreet; Dong, Frank
2013-06-01
The purpose of this article is to determine the decrease in volume CT dose index (CTDI(vol)) and dose-length product (DLP) achieved by switching from fixed quality reference tube current protocols with automatic tube current modulation to protocols adjusting the quality reference tube current, slice collimation, and peak kilovoltage according to patient weight. All adult patients who underwent CT examinations of the abdomen or abdomen and pelvis during 2010 using weight-based protocols who also underwent a CT examination in 2008 or 2009 using fixed quality reference tube current protocols were identified from the radiology information system. Protocol pages were electronically retrieved, and the CT model, examination date, scan protocol, CTDI(vol), and DLP were extracted from the DICOM header or by optical character recognition. There were 15,779 scans with dose records for 2700 patients. Changes in CTDI(vol) and DLP were compared only between examinations of the same patient and same CT system model for examinations performed in 2008 or 2009 and those performed in 2010. The final analysis consisted of 1117 comparisons in 1057 patients, and 1209 comparisons in 988 patients for CTDI(vol) and DLP, respectively. The change to a weight-based protocol resulted in a statistically significant reduction in CTDI(vol) and DLP on three MDCT system models (p < 0.001). The largest average CTDI(vol) decrease was 13.9%, and the largest average DLP decrease was 16.1% on a 64-MDCT system. Both the CTDI(vol) and DLP decreased the most for patients who weighed less than 250 lb (112.5 kg). Adjusting the CT protocol by selecting parameters according to patient weight is a viable method for reducing CT radiation dose. The largest reductions occurred in the patients weighing less than 250 lb.
Tan, J S P; Tan, K-L; Lee, J C L; Wan, C-M; Leong, J-L; Chan, L-L
2009-02-01
To our knowledge, there has been no study that compares the radiation dose delivered to the eye lens by 16- and 64-section multidetector CT (MDCT) for standard clinical neuroimaging protocols. Our aim was to assess radiation-dose differences between 16- and 64-section MDCT from the same manufacturer, by using near-identical neuroimaging protocols. Three cadaveric heads were scanned on 16- and 64-section MDCT by using standard neuroimaging CT protocols. Eye lens dose was measured by using thermoluminescent dosimeters (TLD), and each scanning was repeated to reduce random error. The dose-length product, volume CT dose index (CTDI(vol)), and TLD readings for each imaging protocol were averaged and compared between scanners and protocols, by using the paired Student t test. Statistical significance was defined at P < .05. The radiation dose delivered and eye lens doses were lower by 28.1%-45.7% (P < .000) on the 64-section MDCT for near-identical imaging protocols. On the 16-section MDCT, lens dose reduction was greatest (81.1%) on a tilted axial mode, compared with a nontilted helical mode for CT brain scans. Among the protocols studied, CT of the temporal bone delivered the greatest radiation dose to the eye lens. Eye lens radiation doses delivered by the 64-section MDCT are significantly lower, partly due to improvements in automatic tube current modulation technology. However, where applicable, protection of the eyes from the radiation beam by either repositioning the head or tilting the gantry remains the best way to reduce eye lens dose.
Kuttner, Samuel; Bujila, Robert; Kortesniemi, Mika; Andersson, Henrik; Kull, Love; Østerås, Bjørn Helge; Thygesen, Jesper; Tarp, Ivanka Sojat
2013-03-01
Quality assurance (QA) of computed tomography (CT) systems is one of the routine tasks for medical physicists in the Nordic countries. However, standardized QA protocols do not yet exist and the QA methods, as well as the applied tolerance levels, vary in scope and extent at different hospitals. To propose a standardized protocol for acceptance and constancy testing of CT scanners in the Nordic Region. Following a Nordic Association for Clinical Physics (NACP) initiative, a group of medical physicists, with representatives from four Nordic countries, was formed. Based on international literature and practical experience within the group, a comprehensive standardized test protocol was developed. The proposed protocol includes tests related to the mechanical functionality, X-ray tube, detector, and image quality for CT scanners. For each test, recommendations regarding the purpose, equipment needed, an outline of the test method, the measured parameter, tolerance levels, and the testing frequency are stated. In addition, a number of optional tests are briefly discussed that may provide further information about the CT system. Based on international references and medical physicists' practical experiences, a comprehensive QA protocol for CT systems is proposed, including both acceptance and constancy tests. The protocol may serve as a reference for medical physicists in the Nordic countries.
Boutin, A
2017-01-01
Abstract BACKGROUND: Febrile neonates are at high risk of morbidity and mortality from infectious causes. This risk further increases if antibiotics are not received in a timely manner. Current guidelines recommend early initiation (less than 1 hour) of antibiotics for patients with severe sepsis. Time-to-antibiotic administration (TAA) should also be targeted as a quality-of-care (QOC) measure for febrile neonates. A previous evaluation showed that most of these patients were not receiving antibiotics in the first hour at our emergency department (ED). OBJECTIVES: We evaluated whether a simple quality improvement protocol would improve the proportion of febrile neonates receiving antibiotics within 60 minutes of arrival to the ED. DESIGN/METHODS: This was a pre-post intervention study conducted in the ED of an academic pediatric tertiary care hospital with an annual volume of approximately 83,000 patients in 2014-2016. Participants were a random sample of all children younger than 28 days old visiting the ED for a febrile illness. The new protocol, which consisted for the nurses, after triage, to place the patients directly in the resuscitation room for immediate assessment by a physician, was implemented in February 2016. Previously, these children were triaged level 2 on the Canadian Triage and Acuity Scale (CTAS), flagged and placed in a regular examination room waiting for the physician assessment. With the new protocol, IV access, blood culture, urine analysis and culture were immediately obtained by the nurse in charge with the concomitant assessment by the attending physician. Forty charts prior to and 50 charts after protocol initiation were reviewed by an archivist using a standardized form between 2014-2015 and 2016, respectively. The primary outcome was TAA. This was defined as the time from initial ED registration to the beginning of antibiotics infusion. As a secondary outcome, all cases were reviewed individually to determine barriers to rapid antibiotic administration (day, evening, or night shifts, other treatments or investigations, number of attempts for intravenous access) and to elicit new quality improvement strategies. RESULTS: During the study periods a total of 178 (pre) and 135 (post) patients fulfilled the inclusion criteria. Among the random samples, 6/50 (12%) of patients received their antibiotics within 60 minutes in the post-intervention period compared to 0/40 (0%) in the pre-implementation period (difference 12%; 95 CI: 1-24%). Within 90 minutes, the proportion improved from 1/40 (2.5%) to 29/50 (58%) (difference 56%; 95 CI: 38-68%). Median TAA in febrile neonates decreased from 182 minutes (interquartile range, 147-219 minutes) in the pre-implementation period to 85 minutes (interquartile range, 73-115 minutes) in the post-implementation period. The main obstacle to the goal of 60 minutes for TAA was the difficulty to get IV access as well as antibiotic availability. CONCLUSION: In this study, a new protocol mandating the immediate transfer of febrile neonate from triage to the resuscitation room improved proportion of febrile neonates receiving antibiotics in less than 60 minutes in our ED. Our results suggest that simple interventions can reduce TAA in a selected group of patients presenting to the ED.
De Bondt, Timo; Mulkens, Tom; Zanca, Federica; Pyfferoen, Lotte; Casselman, Jan W; Parizel, Paul M
2017-02-01
To benchmark regional standard practice for paediatric cranial CT-procedures in terms of radiation dose and acquisition parameters. Paediatric cranial CT-data were retrospectively collected during a 1-year period, in 3 different hospitals of the same country. A dose tracking system was used to automatically gather information. Dose (CTDI and DLP), scan length, amount of retakes and demographic data were stratified by age and clinical indication; appropriate use of child-specific protocols was assessed. In total, 296 paediatric cranial CT-procedures were collected. Although the median dose of each hospital was below national and international diagnostic reference level (DRL) for all age categories, statistically significant (p-value < 0.001) dose differences among hospitals were observed. The hospital with lowest dose levels showed smallest dose variability and used age-stratified protocols for standardizing paediatric head exams. Erroneous selection of adult protocols for children still occurred, mostly in the oldest age-group. Even though all hospitals complied with national and international DRLs, dose tracking and benchmarking showed that further dose optimization and standardization is possible by using age-stratified protocols for paediatric cranial CT. Moreover, having a dose tracking system revealed that adult protocols are still applied for paediatric CT, a practice that must be avoided. • Significant differences were observed in the delivered dose between age-groups and hospitals. • Using age-adapted scanning protocols gives a nearly linear dose increase. • Sharing dose-data can be a trigger for hospitals to reduce dose levels.
Avanesov, Maxim; Weinrich, Julius M; Kraus, Thomas; Derlin, Thorsten; Adam, Gerhard; Yamamura, Jin; Karul, Murat
2016-11-01
The purpose of the retrospective study was to evaluate the additional value of dual-phase multidetector computed tomography (MDCT) protocols over a single-phase protocol on initial MDCT in patients with acute pancreatitis using three CT-based pancreatitis severity scores with regard to radiation dose. In this retrospective, IRB approved study MDCT was performed in 102 consecutive patients (73 males; 55years, IQR48-64) with acute pancreatitis. Inclusion criteria were CT findings of interstitial edematous pancreatitis (IP) or necrotizing pancreatitis (NP) and a contrast-enhanced dual-phase (arterial phase and portal-venous phase) abdominal CT performed at ≥72h after onset of symptoms. The severity of pancreatic and extrapancreatic changes was independently assessed by 2 observers using 3 validated CT-based scoring systems (CTSI, mCTSI, EPIC). All scores were applied to arterial phase and portal venous phase scans and compared to score results of portal venous phase scans, assessed ≥14days after initial evaluation. For effective dose estimation, volume CT dose index (CTDIvol) and dose length product (DLP) were recorded in all examinations. In neither of the CT severity scores a significant difference was observed after application of a dual-phase protocol compared with a single-phase protocol (IP: CTSI: 2.7 vs. 2.5, p=0.25; mCTSI: 4.0 vs. 4.0, p=0.10; EPIC: 2.0 vs. 2.0, p=0.41; NP: CTSI: 8.0 vs. 7.0, p=0.64; mCTSI: 8.0 vs. 8.0, p=0.10; EPIC: 3.0 vs. 3.0, p=0.06). The application of a single-phase CT protocol was associated with a median effective dose reduction of 36% (mean dose reduction 31%) compared to a dual-phase CT scan. An initial dual-phase abdominal CT after ≥72h after onset of symptoms of acute pancreatitis was not superior to a single-phase protocol for evaluation of the severity of pancreatic and extrapancreatic changes. However, the effective radiation dose may be reduced by 36% using a single-phase protocol. Copyright © 2016. Published by Elsevier Ireland Ltd.
Hammond, Emily; Sloan, Chelsea; Newell, John D; Sieren, Jered P; Saylor, Melissa; Vidal, Craig; Hogue, Shayna; De Stefano, Frank; Sieren, Alexa; Hoffman, Eric A; Sieren, Jessica C
2017-09-01
Quantitative computed tomography (CT) measures are increasingly being developed and used to characterize lung disease. With recent advances in CT technologies, we sought to evaluate the quantitative accuracy of lung imaging at low- and ultralow-radiation doses with the use of iterative reconstruction (IR), tube current modulation (TCM), and spectral shaping. We investigated the effect of five independent CT protocols reconstructed with IR on quantitative airway measures and global lung measures using an in vivo large animal model as a human subject surrogate. A control protocol was chosen (NIH-SPIROMICS + TCM) and five independent protocols investigating TCM, low- and ultralow-radiation dose, and spectral shaping. For all scans, quantitative global parenchymal measurements (mean, median and standard deviation of the parenchymal HU, along with measures of emphysema) and global airway measurements (number of segmented airways and pi10) were generated. In addition, selected individual airway measurements (minor and major inner diameter, wall thickness, inner and outer area, inner and outer perimeter, wall area fraction, and inner equivalent circle diameter) were evaluated. Comparisons were made between control and target protocols using difference and repeatability measures. Estimated CT volume dose index (CTDIvol) across all protocols ranged from 7.32 mGy to 0.32 mGy. Low- and ultralow-dose protocols required more manual editing and resolved fewer airway branches; yet, comparable pi10 whole lung measures were observed across all protocols. Similar trends in acquired parenchymal and airway measurements were observed across all protocols, with increased measurement differences using the ultralow-dose protocols. However, for small airways (1.9 ± 0.2 mm) and medium airways (5.7 ± 0.4 mm), the measurement differences across all protocols were comparable to the control protocol repeatability across breath holds. Diameters, wall thickness, wall area fraction, and equivalent diameter had smaller measurement differences than area and perimeter measurements. In conclusion, the use of IR with low- and ultralow-dose CT protocols with CT volume dose indices down to 0.32 mGy maintains selected quantitative parenchymal and airway measurements relevant to pulmonary disease characterization. © 2017 American Association of Physicists in Medicine.
Rethinking transitions of care: An interprofessional transfer triage protocol in post-acute care.
Patel, Radha V; Wright, Lauri; Hay, Brittany
2017-09-01
Readmissions to hospitals from post-acute care (PAC) units within long-term care settings have been rapidly increasing over the past decade, and are drivers of increased healthcare costs. With an average of $11,000 per admission, there is a need for strategies to reduce 30-day preventable hospital readmission rates. In 2018, incentives and penalties will be instituted for long-term care facilities failing to meet all-cause, all-condition hospital readmission rate performance measures. An interprofessional team (IPT) developed and implemented a Transfer Triage Protocol used in conjunction with the INTERACT programme to enhance clinical decision-making and assess the potential to reduce the facility's 30-day preventable hospital readmission rates by 10% within 6 weeks of implementation. Results from quantitative analysis demonstrated an overall 35.2% reduction in the 30-day preventable hospital readmission rate. Qualitative analysis revealed the need for additional staff education, improved screening and communication upon admission and prior to hospital transfer, and the need for more IPT on-site availability. This pilot study demonstrates the benefits and implications for practice of an IPT to improve the quality of care within PAC and decrease 30-day preventable hospital readmissions.
Trends of CT utilisation in an emergency department in Taiwan: a 5-year retrospective study
Hu, Sung-Yuan; Hsieh, Ming-Shun; Lin, Meng-Yu; Hsu, Chiann-Yi; Lin, Tzu-Chieh; How, Chorng-Kuang; Wang, Chen-Yu; Tsai, Jeffrey Che-Hung; Wu, Yu-Hui; Chang, Yan-Zin
2016-01-01
Objectives To investigate the association between the trends of CT utilisation in an emergency department (ED) and changes in clinical imaging practice and patients' disposition. Setting A hospital-based retrospective observational study of a public 1520-bed referral medical centre in Taiwan. Participants Adult ED visits (aged ≥18 years) during 2009–2013, with or without receiving CT, were enrolled as the study participants. Main outcome measures For all enrolled ED visits, we retrospectively analysed: (1) demographic characteristics, (2) triage categories, (3) whether CT was performed and the type of CT scan, (4) further ED disposition, (5) ED cost and (6) ED length of stay. Results In all, 269 239 adult ED visits (148 613 male patients and 120 626 female patients) were collected during the 5-year study period, comprising 38 609 CT scans. CT utilisation increased from 11.10% in 2009 to 17.70% in 2013 (trend test, p<0.001). Four in 5 types of CT scan (head, chest, abdomen and miscellaneous) were increasingly utilised during the study period. Also, CT was increasingly ordered annually in all age groups. Although ED CT utilisation rates increased markedly, the annual ED visits did not actually increase. Moreover, the subsequent admission rate, after receiving ED CT, declined (59.9% in 2009 to 48.2% in 2013). Conclusions ED CT utilisation rates increased significantly during 2009–2013. Emergency physicians may be using CT for non-emergent studies in the ED. Further investigation is needed to determine whether increasing CT utilisation is efficient and cost-effective. PMID:27279477
Dose uniformity analysis among ten 16-slice same-model CT scanners.
Erdi, Yusuf Emre
2012-01-01
With the introduction of multislice scanners, computed tomographic (CT) dose optimization has become important. The patient-absorbed dose may differ among the scanners although they are the same type and model. To investigate the dose output variation of the CT scanners, we designed the study to analyze dose outputs of 10 same-model CT scanners using 3 clinical protocols. Ten GE Lightspeed (GE Healthcare, Waukesha, Wis) 16-slice scanners located at main campus and various satellite locations of our institution have been included in this study. All dose measurements were performed using poly (methyl methacrylate) (PMMA) head (diameter, 16 cm) and body (diameter, 32 cm) phantoms manufactured by Radcal (RadCal Corp, Monrovia, Calif) using a 9095 multipurpose analyzer with 10 × 9-3CT ion chamber both from the same manufacturer. Ion chamber is inserted into the peripheral and central axis locations and volume CT dose index (CTDIvol) is calculated as weighted average of doses at those locations. Three clinical protocol settings for adult head, high-resolution chest, and adult abdomen are used for dose measurements. We have observed up to 9.4% CTDIvol variation for the adult head protocol in which the largest variation occurred among the protocols. However, head protocol uses higher milliampere second values than the other 2 protocols. Most of the measured values were less than the system-stored CTDIvol values. It is important to note that reduction in dose output from tubes as they age is expected in addition to the intrinsic radiation output fluctuations of the same scanner. Although the same model CT scanners were used in this study, it is possible to see CTDIvol variation in standard patient scanning protocols of head, chest, and abdomen. The compound effect of the dose variation may be larger with higher milliampere and multiphase and multilocation CT scans.
Vassalou, Evangelia E; Raissaki, Maria; Magkanas, Eleftherios; Antoniou, Katerina M; Karantanas, Apostolos H
2018-03-01
To compare a simplified ultrasonographic (US) protocol in 2 patient positions with the same-positioned comprehensive US assessments and high-resolution computed tomographic (CT) findings in patients with idiopathic pulmonary fibrosis. Twenty-five consecutive patients with idiopathic pulmonary fibrosis were prospectively enrolled and examined in 2 sessions. During session 1, patients were examined with a US protocol including 56 lung intercostal spaces in supine/sitting (supine/sitting comprehensive protocol) and lateral decubitus (decubitus comprehensive protocol) positions. During session 2, patients were evaluated with a 16-intercostal space US protocol in sitting (sitting simplified protocol) and left/right decubitus (decubitus simplified protocol) positions. The 16 intercostal spaces were chosen according to the prevalence of idiopathic pulmonary fibrosis-related changes on high-resolution CT. The sum of B-lines counted in each intercostal space formed the US scores for all 4 US protocols: supine/sitting and decubitus comprehensive US scores and sitting and decubitus simplified US scores. High-resolution CT-related Warrick scores (J Rheumatol 1991; 18:1520-1528) were compared to US scores. The duration of each protocol was recorded. A significant correlation was found between all US scores and Warrick scores and between simplified and corresponding comprehensive scores (P < .0001). Decubitus simplified US scores showed a slightly higher correlation with Warrick scores compared to sitting simplified US scores. Mean durations of decubitus and sitting simplified protocols were 4.76 and 6.20 minutes, respectively (P < .005). Simplified 16-intercostal space protocols correlated with comprehensive protocols and high-resolution CT findings in patients with idiopathic pulmonary fibrosis. The 16-intercostal space simplified protocol in the lateral decubitus position correlated better with high-resolution CT findings and was less time-consuming compared to the sitting position. © 2017 by the American Institute of Ultrasound in Medicine.
Hartmann, Elizabeth H; Creel, Nathan; Lepard, Jacob; Maxwell, Robert A
2012-07-01
On April 27, 2011, an EF4 (enhanced Fujita scale) tornado struck a 48-mile path across northwest Georgia and southeast Tennessee. Traumatic injuries sustained during this tornado and others in one of the largest tornado outbreaks in history presented to the regional Level I trauma center, Erlanger Health System, in Chattanooga, TN. Patients were triaged per mass casualty protocols through an incident command center and triage officer. Medical staffing was increased to anticipate a large patient load. Records of patients admitted as a result of tornado-related injury were retrospectively reviewed and characterized by the injury patterns, demographics, procedures performed, length of stay, and complications. One hundred four adult patients were treated in the emergency department; of these, 28 (27%) patients required admission to the trauma service. Of those admitted, 16 (57%) were male with an age range of 21 to 87 years old and an average length of stay of 10.9 ± 11.8 days. Eleven (39%) patients required intensive care unit admissions. The most common injuries seen were those of soft tissue, bony fractures, and the chest. Interventions included tube thoracostomies, exploratory laparotomies, orthopedic fixations, soft tissue reconstructions, and craniotomy. All 28 patients admitted survived to discharge. Nineteen (68%) patients were discharged home, six (21%) went to a rehabilitation hospital, and three (11%) were transferred to skilled nursing facilities. Emergency preparedness and organization are key elements in effectively treating victims of natural disasters. Those victims who survive the initial tornadic event and present to a Level I trauma center have low mortality. Like in our experience, triage protocols need to be implemented to quickly and effectively manage mass injuries.
SU-C-9A-06: The Impact of CT Image Used for Attenuation Correction in 4D-PET
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cui, Y; Bowsher, J; Yan, S
2014-06-01
Purpose: To evaluate the appropriateness of using 3D non-gated CT image for attenuation correction (AC) in a 4D-PET (gated PET) imaging protocol used in radiotherapy treatment planning simulation. Methods: The 4D-PET imaging protocol in a Siemens PET/CT simulator (Biograph mCT, Siemens Medical Solutions, Hoffman Estates, IL) was evaluated. CIRS Dynamic Thorax Phantom (CIRS Inc., Norfolk, VA) with a moving glass sphere (8 mL) in the middle of its thorax portion was used in the experiments. The glass was filled with {sup 18}F-FDG and was in a longitudinal motion derived from a real patient breathing pattern. Varian RPM system (Varian Medicalmore » Systems, Palo Alto, CA) was used for respiratory gating. Both phase-gating and amplitude-gating methods were tested. The clinical imaging protocol was modified to use three different CT images for AC in 4D-PET reconstruction: first is to use a single-phase CT image to mimic actual clinical protocol (single-CT-PET); second is to use the average intensity projection CT (AveIP-CT) derived from 4D-CT scanning (AveIP-CT-PET); third is to use 4D-CT image to do the phase-matched AC (phase-matching- PET). Maximum SUV (SUVmax) and volume of the moving target (glass sphere) with threshold of 40% SUVmax were calculated for comparison between 4D-PET images derived with different AC methods. Results: The SUVmax varied 7.3%±6.9% over the breathing cycle in single-CT-PET, compared to 2.5%±2.8% in AveIP-CT-PET and 1.3%±1.2% in phasematching PET. The SUVmax in single-CT-PET differed by up to 15% from those in phase-matching-PET. The target volumes measured from single- CT-PET images also presented variations up to 10% among different phases of 4D PET in both phase-gating and amplitude-gating experiments. Conclusion: Attenuation correction using non-gated CT in 4D-PET imaging is not optimal process for quantitative analysis. Clinical 4D-PET imaging protocols should consider phase-matched 4D-CT image if available to achieve better accuracy.« less
Newgard, Craig D.; Mann, N. Clay; Hsia, Renee Y.; Bulger, Eileen M.; Ma, O. John; Staudenmayer, Kristan; Haukoos, Jason S.; Sahni, Ritu; Kuppermann, Nathan
2013-01-01
Objectives Reasons for under-triage (transporting seriously injured patients to non-trauma centers) and the apparent lack of benefit of trauma centers among older adults remain unclear; understanding emergency medical services (EMS) provider reasons for selecting certain hospitals in trauma systems may provide insight to these issues. In this study, the authors evaluated reasons cited by EMS providers for selecting specific hospital destinations for injured patients, stratified by age, injury severity, field triage status, and prognosis. Methods This was a retrospective cohort study of injured children and adults transported by 61 EMS agencies to 93 hospitals (trauma and non-trauma centers) in five regions of the western United States from 2006 through 2008. Hospital records were probabilistically linked to EMS records using trauma registries, state discharge data, and emergency department (ED) data. The seven standardized reasons cited by EMS providers for selecting hospital destinations included: closest facility, ambulance diversion, physician choice, law enforcement choice, patient or family choice, specialty resource center, and other. “Serious injury” was defined as an Injury Severity Score (ISS) ≥ 16, and unadjusted in-hospital mortality was considered as a marker of prognosis. All analyses were stratified by age in 10-year increments, and descriptive statistics were used to characterize the findings. Results A total of 176,981 injured patients were evaluated and transported by EMS over the three-year period, of whom 5,752 (3.3%) had ISS ≥ 16, and 2,773 (1.6%) died. Patient or family choice (50.6%), closest facility (20.7%), and specialty resource center (15.2%) were the most common reasons indicated by EMS providers for selecting destination hospitals; these frequencies varied substantially by patient age. The frequency of patient or family choice increased with increasing age, from 36.4% among 21 to 30 year olds to 75.8% among those older than 90 years. This trend paralleled under-triage rates, and persisted when restricted to patients with serious injuries. Older patients with the worst prognoses were preferentially transported to major trauma centers, a finding that was not explained by field triage protocols. Conclusions Emergency medical services transport patterns among injured patients are not random, even after accounting for field triage protocols. The selection of hospitals appears to be heavily influenced by patient or family choice, which increases with patient age, and involves inherent differences in patient prognosis. PMID:24050797
Russell, Robert T; Griffin, Russell L; Weinstein, Elizabeth; Billmire, Deborah F
2014-09-01
The incidence of button battery ingestions is increasing and injury due to esophageal impaction begins within minutes of exposure. We changed our management algorithm for suspected button battery ingestions with intent to reduce time to evaluation and operative removal. A retrospective study was performed to identify and evaluate time to treatment and outcome for all esophageal button battery ingestions presenting to a major children's hospital emergency room from February 1, 2010 through February 1, 2012. During the first year, standard emergency room triage (ST) was used. During the second year, the triage protocol was changed and Trauma I triage (TT) was used. 24 children had suspected button battery ingestions with 11 having esophageal impaction. One esophageal impaction was due to 2 stacked coins. Time from arrival in emergency room to battery removal was 183minutes in ST group (n=4) and 33minutes in TT group (n=7) (p=0.04). One patient in ST developed a tracheoesophageal fistula. There were no complications in the TT group. The use of Trauma 1 activations for suspected button battery ingestions has led to more expedient evaluation and shortened time to removal of impacted esophageal batteries. Copyright © 2014 Elsevier Inc. All rights reserved.
Low-voltage chest CT: another way to reduce the radiation dose in asbestos-exposed patients.
Macía-Suárez, D; Sánchez-Rodríguez, E; Lopez-Calviño, B; Diego, C; Pombar, M
2017-09-01
To assess whether low voltage chest computed tomography (CT) can be used to successfully diagnose disease in patients with asbestos exposure. Fifty-six former employees of the shipbuilding industry, who were candidates to receive a standard-dose chest CT due to their occupational exposure to asbestos, underwent a routine CT. Immediately after this initial CT, they underwent a second acquisition using low-dose chest CT parameters, based on a low potential (80 kV) and limited tube current. The findings of the two CT protocols were compared based on typical diseases associated with asbestos exposure. The kappa coefficient for each parameter and for an overall rating (grouping them based on mediastinal, pleural, and pulmonary findings) were calculated in order to test for correlations between the two protocols. A good correlation between routine and low-dose CT was demonstrated for most parameters with a mean radiation dose reduction of up to 83% of the effective dose based on the dose-length product between protocols. Low-dose chest CT, based on a limited tube potential, is useful for patients with an asbestos exposure background. Low-dose chest CT can be successfully used to minimise the radiation dose received by patients, as this protocol produced an estimated mean effective dose similar to that of an abdominal or pelvis plain film. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Chest CT in children: anesthesia and atelectasis.
Newman, Beverley; Krane, Elliot J; Gawande, Rakhee; Holmes, Tyson H; Robinson, Terry E
2014-02-01
There has been an increasing tendency for anesthesiologists to be responsible for providing sedation or anesthesia during chest CT imaging in young children. Anesthesia-related atelectasis noted on chest CT imaging has proven to be a common and troublesome problem, affecting image quality and diagnostic sensitivity. To evaluate the safety and effectiveness of a standardized anesthesia, lung recruitment, controlled-ventilation technique developed at our institution to prevent atelectasis for chest CT imaging in young children. Fifty-six chest CT scans were obtained in 42 children using a research-based intubation, lung recruitment and controlled-ventilation CT scanning protocol. These studies were compared with 70 non-protocolized chest CT scans under anesthesia taken from 18 of the same children, who were tested at different times, without the specific lung recruitment and controlled-ventilation technique. Two radiology readers scored all inspiratory chest CT scans for overall CT quality and atelectasis. Detailed cardiorespiratory parameters were evaluated at baseline, and during recruitment and inspiratory imaging on 21 controlled-ventilation cases and 8 control cases. Significant differences were noted between groups for both quality and atelectasis scores with optimal scoring demonstrated in the controlled-ventilation cases where 70% were rated very good to excellent quality scans compared with only 24% of non-protocol cases. There was no or minimal atelectasis in 48% of the controlled ventilation cases compared to 51% of non-protocol cases with segmental, multisegmental or lobar atelectasis present. No significant difference in cardiorespiratory parameters was found between controlled ventilation and other chest CT cases and no procedure-related adverse events occurred. Controlled-ventilation infant CT scanning under general anesthesia, utilizing intubation and recruitment maneuvers followed by chest CT scans, appears to be a safe and effective method to obtain reliable and reproducible high-quality, motion-free chest CT images in children.
Comparison of the 1999 and 2006 Trauma Triage Guidelines: Where do Patients Go?
Lerner, E. Brooke; Shah, Manish N.; Swor, Robert; Cushman, Jeremy T.; Guse, Clare E.; Brasel, Karen; Blatt, Alan; Jurkovich, Gregory J.
2010-01-01
In 2006, the CDC released a revised Field Triage Decision Scheme. It is unknown how this modified scheme will affect the number of patients identified by EMS for transport to a trauma center. Objective To determine the change in the number of patients transported by EMS who meet the 2006 scheme, compared to the 1999 scheme, and to determine how the scheme change would affect under- and over-triage rates. Methods EMS providers in charge of care for injured adult patients transported to a regional trauma center in three mid-sized cities were interviewed immediately after completing transport. All injured patients were included, regardless of severity. The interview included patient demographics, vital signs, apparent anatomic injury, and the mechanism of injury. Included patients were then followed through hospital discharge. The 1999 and 2006 scheme criteria were each retrospectively applied to the collected data. The number of patients identified by the two schemes was determined. Patients were considered to have needed a trauma center if they had non-orthopedic surgery within 24 hours, ICU admission, or died. Data were analyzed using descriptive statistics including 95% confidence intervals. Results EMS interviews were conducted for 11,892 patients and outcome data was unavailable for one patient. Average patient age was 48 years; 51% were men. Providers reported bringing 54% of the enrolled patients to the trauma center based on their local trauma protocol. 12% of enrolled patients were identified as needing a trauma center based on medical record review. Use of the 2006 scheme would have resulted in 1,423 fewer patients (12%; 95% CI:11-13%) being identified as needing a trauma center by EMS providers (40%; 95%CI:39-41% versus 28%; 95%CI:27-29%). 1,344 of those patients did not actually need the resources of a trauma center (94%). 78 (6%) of those patients actually needed the resources of a trauma center and would have been under-triaged. Conclusion Use of the 2006 Field Triage Decision Scheme would have resulted in a significant decrease in the number of patients identified as needing the resources of a trauma center. These changes reduced over-triage while causing a small increase in the number of patients who would have been under-triaged. PMID:21054176
2018-01-01
Objective To compare radiation doses between conventional and chest pain protocols using dual-source retrospectively electrocardiography (ECG)-gated cardiothoracic computed tomography (CT) in children and adults and assess the effect of tube current saturation on radiation dose reduction. Materials and Methods This study included 104 patients (16.6 ± 7.7 years, range 5–48 years) that were divided into two groups: those with and those without tube current saturation. The estimated radiation doses of retrospectively ECG-gated spiral cardiothoracic CT were compared between conventional, uniphasic, and biphasic chest pain protocols acquired with the same imaging parameters in the same patients by using paired t tests. Dose reduction percentages, patient ages, volume CT dose index values, and tube current time products per rotation were compared between the two groups by using unpaired t tests. A p value < 0.05 was considered significant. Results The volume CT dose index values of the biphasic chest pain protocol (10.8 ± 3.9 mGy) were significantly lower than those of the conventional protocol (12.2 ± 4.7 mGy, p < 0.001) and those of the uniphasic chest pain protocol (12.9 ± 4.9 mGy, p < 0.001). The dose-saving effect of biphasic chest pain protocol was significantly less with a saturated tube current (4.5 ± 10.2%) than with unsaturated tube current method (14.8 ± 11.5%, p < 0.001). In 76 patients using 100 kVp, patient age showed no significant differences between the groups with and without tube current saturation in all protocols (p > 0.05); the groups with tube current saturation showed significantly higher volume CT dose index values (p < 0.01) and tube current time product per rotation (p < 0.001) than the groups without tube current saturation in all protocols. Conclusion The radiation dose of dual-source retrospectively ECG-gated spiral cardiothoracic CT can be reduced by approximately 15% by using the biphasic chest pain protocol instead of the conventional protocol in children and adults if radiation dose parameters are further optimized to avoid tube current saturation. PMID:29353996
Resurfacing the care in nursing by telephone: lessons from ambulatory oncology.
Wilson, Rosemary; Hubert, John
2002-01-01
The practice of providing telephone mediated advice and assistance is often described as "telephone triage" in relevant literature. The decision-making processes required for priority-setting and the provision of advice have been found to be complex and multifaceted. Conceptualization of this valuable patient care activity as a linear "triage" function serves to make invisible the nursing care provided. This article explores the current practice of providing telephone mediated advice and assistance in the following 2 distinct nursing care settings: emergency departments and ambulatory oncology centers. Examination of this activity in these 2 settings provides a forum to discuss and critique legally and fiscally driven prescriptive protocol use to inform decision-making. The effectiveness of experiential knowledge coupled with the strengths of nurse-patient relationships suggests that a need exists to highlight the caring aspects of telephone mediated assistance.
Homedes, Núria; Ugalde, Antonio
2015-06-01
To assess the potential role of clinical trial (CT) registries and other resources available to research ethics committees (RECs) in the evaluation of complex CT protocols in low-income and middle-income countries. Using a case study approach, the authors examined the decision-making process of a REC in Argentina and its efforts to use available resources to decide on a complex protocol. We also analysed the information in the USA and other CT registries and consulted 24 CT experts in seven countries. Information requested by the Argentinean REC from other national RECs and ethics' experts was not useful to verify the adequacy of the REC's decision whether or not to approve the CT. The responses from the national regulatory agency and the sponsor were not helpful either. The identification of international resources that could assist was beyond the REC's capability. The information in the USA and other CT registries is limited, and at times misleading; and its accuracy is not verified by register keepers. RECs have limited access to experts and institutions that could assist them in their deliberations. Sponsors do not always answer RECs' request for information to properly conduct the ethical and methodological assessment of CT protocols. The usefulness of the CT registries is curtailed by the lack of appropriate codes and by data errors. Information about reasons for rejection, withdrawal or suspension of the trial should be included in the registries. Establishing formal channels of communication among national and foreign RECs and with independent international reference centres could strengthen the ethical review of CT protocols. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Rehak, Z; Vasina, J; Ptacek, J; Kazda, T; Fojtik, Z; Nemec, P
18 F-FDG PET/CT imaging is useful in patients with fever of unknown origin and can detect giant cell arteritis in extracranial large arteries. However, it is usually assumed that temporal arteries cannot be visualized with a PET/CT scanner due to their small diameter. Three patients with clinical symptoms of temporal arteritis were examined using a standard whole body PET/CT protocol (skull base - mid thighs) followed by a head PET/CT scan using the brain protocol. High 18 F-FDG uptake in the aorta and some arterial branches were detected in all 3 patients with the whole body protocol. Using the brain protocol, head imaging led to detection of high 18 F-FDG uptake in temporal arteries as well as in their branches (3 patients), in occipital arteries (2 patients) and also in vertebral arteries (3 patients). Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.
Nishijima, Daniel Kiden; Gaona, Samuel D; Waechter, Trent; Maloney, Ric; Blitz, Adam; Elms, Andrew R; Farrales, Roel D; Montoya, James; Bair, Troy; Howard, Calvin; Gilbert, Megan; Trajano, Renee; Hatchel, Kaela; Faul, Mark; Bell, Jeneita M; Coronado, Victor; Vinson, David R; Ballard, Dustin W; Tancredi, Daniel J; Garzon, Hernando; Mackey, Kevin E; Shahlaie, Kiarash; Holmes, James F
2017-11-06
Field triage guidelines recommend transport of head-injured patients on anticoagulants or antiplatelets to a higher-level trauma center based on studies suggesting a high incidence of traumatic intracranial hemorrhage (tICH). We compared the incidence of tICH in older adults transported by EMS with and without anticoagulation or antiplatelet use and evaluated the accuracies of different sets of field triage criteria to identify tICH. This was a prospective, observational study at 5 EMS agencies and 11 hospitals. Older adults (≥55 years) with head trauma and transported by EMS from Aug 2015 to Sept 2016 were eligible. EMS providers completed standardized data forms and patients were followed through ED or hospital discharge. We enrolled 1,304 patients; 1147 (88%) received a cranial CT scan and were eligible for analysis. 434 (33%) patients had anticoagulant or antiplatelet use and 112 (10%) had tICH. The incidence of tICH in patients with (11%, 95%CI 8-14%) and without (9%, 95%CI 7-11%) anticoagulant or antiplatelet use was similar. Anticoagulant or antiplatelet use was not predictive of tICH on adjusted analysis. Steps 1-3 criteria alone were not sensitive in identifying tICH (27%) while the addition of anticoagulant or antiplatelet criterion improved sensitivity (63%). Other derived sets of triage criteria were highly sensitive (>98%) but poorly specific (<11%). The incidence of tICH was similar between patients with and without anticoagulant or antiplatelet use. Use of anticoagulant or antiplatelet medications was not a risk factor for tICH. We were unable to identify a set of triage criteria that was accurate for trauma center need.
NASA Astrophysics Data System (ADS)
Balcerzyk, Marcin; Fernández-López, Rosa; Parrado-Gallego, Ángel; Pachón-Garrudo, Víctor Manuel; Chavero-Royan, José; Hevilla, Juan; Jiménez-Ortega, Elisa; Leal, Antonio
2017-11-01
Tumour uptake value is a critical result in [18F]FDG-PET/CT ([18F]fluorodeoxyglucose) quantitative scans such as the dose prescription for radiotherapy and oncology. The quantification is highly dependent on the protocol of acquisition and reconstruction of the image, especially in low activity tumours. During adjusting acquisition and reconstruction protocols available in our Siemens Biograph mCT scanner for EARL (ResEARch 4 Life®) [18F]FDG-PET/CT accreditation requirements, we developed reconstruction protocols which will be used in PET based radiotherapy planning able to reduce inter-/intra-institute variability in Standard Uptake Value (SUV) results, and to bring Recovery Coefficient to 1 as close as possible for Image Quality NEMA 2007 phantom. Primary and secondary tumours from two patients were assessed by four independent evaluators. The influence of reconstruction protocols on tumour clinical assessment was presented. We proposed the improvement route for EARL accredited protocols so that they may be developed in classes to take advantage of scanner possibilities. The application of optimized reconstruction protocol eliminates the need of partial volume corrections.
Tailoring protocols for chest CT applications: when and how?
Iezzi, Roberto; Larici, Anna Rita; Franchi, Paola; Marano, Riccardo; Magarelli, Nicola; Posa, Alessandro; Merlino, Biagio; Manfredi, Riccardo; Colosimo, Cesare
2017-01-01
In the medical era of early detection of diseases and tailored therapies, an accurate characterization and staging of the disease is pivotal for treatment planning. The widespread use of computed tomography (CT)—often with the use of contrast material (CM)—probably represents the most important advance in diagnostic radiology. The result is a marked increase in radiation exposure of the population for medical purposes, with its intrinsic carcinogenic potential, and CM affecting kidney function. The radiologists should aim to minimize patient’s risk by reducing radiation exposure and CM amount, while maintaining the highest image quality. To achieve this goal, it is necessary to perform “patient-centric imaging”. The purpose of this review is to provide radiologists with “tips and tricks” to control radiation dose at CT, summarizing technical artifices in order to reduce image noise and increase image contrast. Also chest CT tailored protocols are supplied, with particular attention to three most common thoracic CT protocols: aortic/cardiac CT angiography (CTA), pulmonary CTA, and routine chest CT. PMID:29097345
Sachs, Peter B; Hunt, Kelly; Mansoubi, Fabien; Borgstede, James
2017-02-01
Building and maintaining a comprehensive yet simple set of standardized protocols for a cross-sectional image can be a daunting task. A single department may have difficulty preventing "protocol creep," which almost inevitably occurs when an organized "playbook" of protocols does not exist and individual radiologists and technologists alter protocols at will and on a case-by-case basis. When multiple departments or groups function in a large health system, the lack of uniformity of protocols can increase exponentially. In 2012, the University of Colorado Hospital formed a large health system (UCHealth) and became a 5-hospital provider network. CT and MR imaging studies are conducted at multiple locations by different radiology groups. To facilitate consistency in ordering, acquisition, and appearance of a given study, regardless of location, we minimized the number of protocols across all scanners and sites of practice with a clinical indication-driven protocol selection and standardization process. Here we review the steps utilized to perform this process improvement task and insure its stability over time. Actions included creation of a standardized protocol template, which allowed for changes in electronic storage and management of protocols, designing a change request form, and formation of a governance structure. We utilized rapid improvement events (1 day for CT, 2 days for MR) and reduced 248 CT protocols into 97 standardized protocols and 168 MR protocols to 66. Additional steps are underway to further standardize output and reporting of imaging interpretation. This will result in an improved, consistent radiologist, patient, and provider experience across the system.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lipnharski, I; Quails, N; Carranza, C
Purpose: The imaging of pregnant patients is medically necessary in certain clinical situations. The purpose of this work was to directly measure uterine doses in a cadaver scanned with CT protocols commonly performed on pregnant patients in order to estimate fetal dose and assess potential risk. Method: One postmortem subject was scanned on a 320-slice CT scanner with standard pulmonary embolism, trauma, and appendicitis protocols. All protocols were performed with the scan parameters and ranges currently used in clinical practice. Exams were performed both with and without iterative reconstruction to highlight the dose savings potential. Optically stimulated luminescent dosimeters (OSLDs)more » were inserted into the uterus in order to approximate fetal doses. Results: In the pulmonary embolism CT protocol, the uterus is outside of the primary beam, and the dose to the uterus was under 1 mGy. In the trauma and appendicitis protocols, the uterus is in the primary beam, the fetal dose estimates were 30.5 mGy for the trauma protocol, and 20.6 mGy for the appendicitis protocol. Iterative reconstruction reduced fetal doses by 30%, with uterine doses at 21.3 for the trauma and 14.3 mGy for the appendicitis protocol. Conclusion: Fetal doses were under 1 mGy when exposed to scatter radiation, and under 50 mGy when exposed to primary radiation with the trauma and appendicitis protocols. Consistent with the National Council on Radiation Protection & Measurements (NCRP) and the International Commission on Radiological Protection (ICRP), these doses exhibit a negligible risk to the fetus, with only a small increased risk of cancer. Still, CT scans are not recommended during pregnancy unless the benefits of the exam clearly outweigh the potential risk. Furthermore, when possible, pregnant patients should be examined on CT scanners equipped with iterative reconstruction in order to keep patient doses as low as reasonable achievable.« less
Simulation Learning PC Screen-Based vs. High Fidelity
2011-08-01
D., Burgess, L., Berg, B . and Connolly, K . (2009). Teaching mass casualty triage skills using iterative multimanikin simulations. Prehospital...SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON USAMRMC a. REPORT U b . ABSTRACT U...learning PC screen-based vs. high fidelity – progress chart Attachment B . Approved Protocol - Simulation Learning: PC-Screen Based (PCSB) versus High
Kwon, Sung Woo; Kim, Young Jin; Shim, Jaemin; Sung, Ji Min; Han, Mi Eun; Kang, Dong Won; Kim, Ji-Ye; Choi, Byoung Wook; Chang, Hyuk-Jae
2011-04-01
To evaluate the prognostic outcome of cardiac computed tomography (CT) for prediction of major adverse cardiac events (MACEs) in low-risk patients suspected of having coronary artery disease (CAD) and to explore the differential prognostic values of coronary artery calcium (CAC) scoring and coronary CT angiography. Institutional review committee approval and informed consent were obtained. In 4338 patients who underwent 64-section CT for evaluation of suspected CAD, both CAC scoring and CT angiography were concurrently performed by using standard scanning protocols. Follow-up clinical outcome data regarding composite MACEs were procured. Multivariable Cox proportional hazards models were developed to predict MACEs. Risk-adjusted models incorporated traditional risk factors for CAC scoring and coronary CT angiography. During the mean follow-up of 828 days ± 380, there were 105 MACEs, for an event rate of 3%. The presence of obstructive CAD at coronary CT angiography had independent prognostic value, which escalated according to the number of stenosed vessels (P < .001). In the receiver operating characteristic curve (ROC) analysis, the superiority of coronary CT angiography to CAC scoring was demonstrated by a significantly greater area under the ROC curve (AUC) (0.892 vs 0.810, P < .001), whereas no significant incremental value for the addition of CAC scoring to coronary CT angiography was established (AUC = 0.892 for coronary CT angiography alone vs 0.902 with addition of CAC scoring, P = .198). Coronary CT angiography is better than CAC scoring in predicting MACEs in low-risk patients suspected of having CAD. Furthermore, the current standard multisection CT protocol (coronary CT angiography combined with CAC scoring) has no incremental prognostic value compared with coronary CT angiography alone. Therefore, in terms of determining prognosis, CAC scoring may no longer need to be incorporated in the cardiac CT protocol in this population. © RSNA, 2011.
Optimization of the protocols for the use of contrast agents in PET/CT studies.
Pelegrí Martínez, L; Kohan, A A; Vercher Conejero, J L
The introduction of PET/CT scanners in clinical practice in 1998 has improved care for oncologic patients throughout the clinical pathway, from the initial diagnosis of disease through the evaluation of the response to treatment to screening for possible recurrence. The CT component of a PET/CT study is used to correct the attenuation of PET studies; CT also provides anatomic information about the distribution of the radiotracer. CT is especially useful in situations where PET alone can lead to false positives and false negatives, and CT thereby improves the diagnostic performance of PET. The use of intravenous or oral contrast agents and optimal CT protocols have improved the detection and characterization of lesions. However, there are circumstances in which the systematic use of contrast agents is not justified. The standard acquisition in PET/CT scanners is the whole body protocol, but this can lead to artifacts due to the position of patients and respiratory movements between the CT and PET acquisitions. This article discusses these aspects from a constructive perspective with the aim of maximizing the diagnostic potential of PET/CT and providing better care for patients. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.
Implementation of lung cancer CT screening in the Nordic countries.
Pedersen, Jesper Holst; Sørensen, Jens Benn; Saghir, Zaigham; Fløtten, Øystein; Brustugun, Odd Terje; Ashraf, Haseem; Strand, Trond-Eirik; Friesland, Signe; Koyi, Hirsh; Ek, Lars; Nyrén, Sven; Bergman, Per; Jekunen, Antti; Nieminen, Eeva-Maija; Gudbjartsson, Tomas
2017-10-01
We review the current knowledge of CT screening for lung cancer and present an expert-based, joint protocol for the proper implementation of screening in the Nordic countries. Experts representing all the Nordic countries performed literature review and concensus for a joint protocol for lung cancer screening. Areas of concern and caution are presented and discussed. We suggest to perform CT screening pilot studies in the Nordic countries in order to gain experience and develop specific and safe protocols for the implementation of such a program.
Scanning and War: Utility of FAST and CT in the Assessment of Battlefield Abdominal Trauma.
Smith, Iain M; Naumann, David N; Marsden, Max E R; Ballard, Mark; Bowley, Douglas M
2015-08-01
To determine utilization and accuracy of focused assessment with sonography for trauma (FAST) and computed tomography (CT) in a mature military trauma system to inform service provision for future conflicts. FAST and CT scans undertaken by attending radiologists contribute to surgical decision making for battlefield casualties at the Joint Force, Role 3 Medical Treatment Facility at Camp Bastion (R3), Afghanistan. Registry data for abdominally injured casualties treated at R3 from July to November 2012 were matched to radiological and surgical records to determine diagnostic accuracy for FAST and CT and their influence on casualty management. A total of 468 casualties met inclusion criteria, of whom 85.0% underwent FAST and 86.1% abdominal CT; 159 (34.0%) had abdominal injuries. For detection of intra-abdominal injury, FAST sensitivity (Sn) was 0.56, specificity (Sp) 0.98, positive predictive value (PPV) 0.87, negative predictive value (NPV) 0.90, and accuracy (Acc) 0.89. For CT, Sn was 0.99, Sp 0.99, PPV 0.96, NPV 1.00, and Acc 0.99. Forty-six solid organ injuries were identified in 38 patients by CT; 17 were managed nonoperatively. A further 61 patients avoided laparotomy after CT confirmed extra-abdominal wounds only. The negative laparotomy rate was 3.9%. FAST and CT contribute to triage, guide surgical management, and reduce nontherapeutic laparotomy. When imaging is available, these data challenge current doctrine about inadvisability of nonoperative management of abdominal injury after combat trauma.
Guberina, Nika; Forsting, Michael; Ringelstein, Adrian
2017-06-15
To evaluate the dose-reduction potential with different lens protectors for patients undergoing cranial computed tomography (CT) scans. Eye lens dose was assessed in vitro (α-Al2O3:C thermoluminescence dosemeters) using an Alderson-Rando phantom® in cranial CT protocols at different CT scanners (SOMATOM-Definition-AS+®(CT1) and SOMATOM-Definition-Flash® (CT2)) using two different lens-protection systems (Somatex® (SOM) and Medical Imaging Systems® (MIS)). Summarised percentage of the transmitted photons: (1) CT1 (a) unenhanced CT (nCT) with gantry angulation: SOM = 103%, MIS = 111%; (2) CT2 (a) nCT without gantry angulation: SOM = 81%, MIS = 91%; (b) CT angiography (CTA) with automatic dose-modulation technique: SOM = 39%, MIS = 74%; (c) CTA without dose-modulation technique: SOM = 22%, MIS = 48%; (d) CT perfusion: SOM = 44%, MIS = 69%. SOM showed a higher dose-reduction potential than MIS maintaining equal image quality. Lens-protection systems are most effective in CTA protocols without dose-reduction techniques. Lens-protection systems lower the average eye lens dose during CT scans up to 1/3 (MIS) and 2/3 (SOM), respectively, if the eye lens is exposed to the direct beam of radiation. Considering both the CT protocol and the material of lens protectors, they seem to be mandatory for reducing the radiation exposure of the eye lens. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Trends of CT utilisation in an emergency department in Taiwan: a 5-year retrospective study.
Hu, Sung-Yuan; Hsieh, Ming-Shun; Lin, Meng-Yu; Hsu, Chiann-Yi; Lin, Tzu-Chieh; How, Chorng-Kuang; Wang, Chen-Yu; Tsai, Jeffrey Che-Hung; Wu, Yu-Hui; Chang, Yan-Zin
2016-06-08
To investigate the association between the trends of CT utilisation in an emergency department (ED) and changes in clinical imaging practice and patients' disposition. A hospital-based retrospective observational study of a public 1520-bed referral medical centre in Taiwan. Adult ED visits (aged ≥18 years) during 2009-2013, with or without receiving CT, were enrolled as the study participants. For all enrolled ED visits, we retrospectively analysed: (1) demographic characteristics, (2) triage categories, (3) whether CT was performed and the type of CT scan, (4) further ED disposition, (5) ED cost and (6) ED length of stay. In all, 269 239 adult ED visits (148 613 male patients and 120 626 female patients) were collected during the 5-year study period, comprising 38 609 CT scans. CT utilisation increased from 11.10% in 2009 to 17.70% in 2013 (trend test, p<0.001). Four in 5 types of CT scan (head, chest, abdomen and miscellaneous) were increasingly utilised during the study period. Also, CT was increasingly ordered annually in all age groups. Although ED CT utilisation rates increased markedly, the annual ED visits did not actually increase. Moreover, the subsequent admission rate, after receiving ED CT, declined (59.9% in 2009 to 48.2% in 2013). ED CT utilisation rates increased significantly during 2009-2013. Emergency physicians may be using CT for non-emergent studies in the ED. Further investigation is needed to determine whether increasing CT utilisation is efficient and cost-effective. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gill, K; Aldoohan, S; Collier, J
Purpose: Study image optimization and radiation dose reduction in pediatric shunt CT scanning protocol through the use of different beam-hardening filters Methods: A 64-slice CT scanner at OU Childrens Hospital has been used to evaluate CT image contrast-to-noise ratio (CNR) and measure effective-doses based on the concept of CT dose index (CTDIvol) using the pediatric head shunt scanning protocol. The routine axial pediatric head shunt scanning protocol that has been optimized for the intrinsic x-ray tube filter has been used to evaluate CNR by acquiring images using the ACR approved CT-phantom and radiation dose CTphantom, which was used to measuremore » CTDIvol. These results were set as reference points to study and evaluate the effects of adding different filtering materials (i.e. Tungsten, Tantalum, Titanium, Nickel and Copper filters) to the existing filter on image quality and radiation dose. To ensure optimal image quality, the scanner routine air calibration was run for each added filter. The image CNR was evaluated for different kVps and wide range of mAs values using above mentioned beam-hardening filters. These scanning protocols were run under axial as well as under helical techniques. The CTDIvol and the effective-dose were measured and calculated for all scanning protocols and added filtration, including the intrinsic x-ray tube filter. Results: Beam-hardening filter shapes energy spectrum, which reduces the dose by 27%. No noticeable changes in image low contrast detectability Conclusion: Effective-dose is very much dependent on the CTDIVol, which is further very much dependent on beam-hardening filters. Substantial reduction in effective-dose is realized using beam-hardening filters as compare to the intrinsic filter. This phantom study showed that significant radiation dose reduction could be achieved in CT pediatric shunt scanning protocols without compromising in diagnostic value of image quality.« less
SU-E-I-68: Practical Considerations On Implementation of the Image Gently Pediatric CT Protocols
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, J; Adams, C; Lumby, C
Purpose: One limitation associated with the Image Gently pediatric CT protocols is practical implementation of the recommended manual techniques. Inconsistency as a result of different practice is a possibility among technologist. An additional concern is the added risk of data error that would result in over or underexposure. The Automatic Exposure Control (AEC) features automatically reduce radiation for children. However, they do not work efficiently for the patients of very small size and relative large size. This study aims to implement the Image Gently pediatric CT protocols in the practical setting while maintaining the use of AEC features for pediatricmore » patients of varying size. Methods: Anthropomorphological abdomen phantoms were scanned in a CT scanner using the Image Gently pediatric protocols, the AEC technique with a fixed adult baseline, and automatic protocols with various baselines. The baselines were adjusted corresponding to patient age, weight and posterioranterior thickness to match the Image Gently pediatric CT manual techniques. CTDIvol was recorded for each examination. Image noise was measured and recorded for image quality comparison. Clinical images were evaluated by pediatric radiologists. Results: By adjusting vendor default baselines used in the automatic techniques, radiation dose and image quality can match those of the Image Gently manual techniques. In practice, this can be achieved by dividing pediatric patients into three major groups for technologist reference: infant, small child, and large child. Further division can be done but will increase the number of CT protocols. For each group, AEC can efficiently adjust acquisition techniques for children. This implementation significantly overcomes the limitation of the Image Gently manual techniques. Conclusion: Considering the effectiveness in clinical practice, Image Gently Pediatric CT protocols can be implemented in accordance with AEC techniques, with adjusted baselines, to achieve the goal of providing the most appropriate radiation dose for pediatric patients of varying sizes.« less
Zarb, Francis; McEntee, Mark F; Rainford, Louise
2015-06-01
To evaluate visual grading characteristics (VGC) and ordinal regression analysis during head CT optimisation as a potential alternative to visual grading assessment (VGA), traditionally employed to score anatomical visualisation. Patient images (n = 66) were obtained using current and optimised imaging protocols from two CT suites: a 16-slice scanner at the national Maltese centre for trauma and a 64-slice scanner in a private centre. Local resident radiologists (n = 6) performed VGA followed by VGC and ordinal regression analysis. VGC alone indicated that optimised protocols had similar image quality as current protocols. Ordinal logistic regression analysis provided an in-depth evaluation, criterion by criterion allowing the selective implementation of the protocols. The local radiology review panel supported the implementation of optimised protocols for brain CT examinations (including trauma) in one centre, achieving radiation dose reductions ranging from 24 % to 36 %. In the second centre a 29 % reduction in radiation dose was achieved for follow-up cases. The combined use of VGC and ordinal logistic regression analysis led to clinical decisions being taken on the implementation of the optimised protocols. This improved method of image quality analysis provided the evidence to support imaging protocol optimisation, resulting in significant radiation dose savings. • There is need for scientifically based image quality evaluation during CT optimisation. • VGC and ordinal regression analysis in combination led to better informed clinical decisions. • VGC and ordinal regression analysis led to dose reductions without compromising diagnostic efficacy.
The feasibility of universal DLP-to-risk conversion coefficients for body CT protocols
NASA Astrophysics Data System (ADS)
Li, Xiang; Samei, Ehsan; Segars, W. Paul; Paulson, Erik K.; Frush, Donald P.
2011-03-01
The effective dose associated with computed tomography (CT) examinations is often estimated from dose-length product (DLP) using scanner-independent conversion coefficients. Such conversion coefficients are available for a small number of examinations, each covering an entire region of the body (e.g., head, neck, chest, abdomen and/or pelvis). Similar conversion coefficients, however, do not exist for examinations that cover a single organ or a sub-region of the body, as in the case of a multi-phase liver examination. In this study, we extended the DLP-to-effective dose conversion coefficient (k factor) to a wide range of body CT protocols and derived the corresponding DLP-to-cancer risk conversion coefficient (q factor). An extended cardiactorso (XCAT) computational model was used, which represented a reference adult male patient. A range of body CT protocols used in clinical practice were categorized based on anatomical regions examined into 10 protocol classes. A validated Monte Carlo program was used to estimate the organ dose associated with each protocol class. Assuming the reference model to be 20 years old, effective dose and risk index (an index of the total risk for cancer incidence) were then calculated and normalized by DLP to obtain the k and q factors. The k and q factors varied across protocol classes; the coefficients of variation were 28% and 9%, respectively. The small variation exhibited by the q factor suggested the feasibility of universal q factors for a wide range of body CT protocols.
Crosbie, Robin A; Nairn, Jonathan; Kubba, Haytham
2016-08-01
Paediatric periorbital cellulitis is a common condition. Accurate assessment can be challenging and appropriate use of CT imaging is essential. We audited admissions to our unit over a four year period, with reference to CT scanning and adherence to our protocol. Retrospective audit of paediatric patients admitted with periorbital cellulitis, 2012-2015. Total of 243 patients included, mean age 4.7 years with slight male predominance, the median length of admission was 2 days. 48/243 (20%) underwent CT during admission, 25 (52%) of these underwent surgical drainage. As per protocol, CT brain performed with all orbital scans; no positive intracranial findings on any initial scan. Three children developed intracranial complications subsequently; all treated with antibiotics. Our re-admission rate within 30 days was 2.5%. Our audit demonstrates benefit of standardising practice and the low CT rate, with high percentage taken to theatre and no missed abscesses, supports the protocol. There may be an argument to avoid CT brain routinely in all initial imaging sequences in those children without neurological signs or symptoms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Iyama, Yuji; Nakaura, Takeshi; Yokoyama, Koichi; Kidoh, Masafumi; Harada, Kazunori; Oda, Seitaro; Tokuyasu, Shinichi; Yamashita, Yasuyuki
This study aimed to evaluate the feasibility of a low contrast, low-radiation dose protocol of 80-peak kilovoltage (kVp) with prospective electrocardiography-gated cardiac computed tomography (CT) using knowledge-based iterative model reconstruction (IMR). Thirty patients underwent an 80-kVp prospective electrocardiography-gated cardiac CT with low-contrast agent (222-mg iodine per kilogram of body weight) dose. We also enrolled 30 consecutive patients who were scanned with a 120-kVp cardiac CT with filtered back projection using the standard contrast agent dose (370-mg iodine per kilogram of body weight) as a historical control group. We evaluated the radiation dose for the 2 groups. The 80-kVp images were reconstructed with filtered back projection (protocol A), hybrid iterative reconstruction (HIR, protocol B), and IMR (protocol C). We compared CT numbers, image noise, and contrast-to-noise ratio among 120-kVp protocol, protocol A, protocol B, and protocol C. In addition, we compared the noise reduction rate between HIR and IMR. Two independent readers compared image contrast, image noise, image sharpness, unfamiliar image texture, and overall image quality among the 4 protocols. The estimated effective dose (ED) of the 80-kVp protocol was 74% lower than that of the 120-kVp protocol (1.4 vs 5.4 mSv). The contrast-to-noise ratio of protocol C was significantly higher than that of protocol A. The noise reduction rate of IMR was significantly higher than that of HIR (P < 0.01). There was no significant difference in almost all qualitative image quality between 120-kVp protocol and protocol C except for image contrast. A 80-kVp protocol with IMR yields higher image quality with 74% decreased radiation dose and 40% decreased contrast agent dose as compared with a 120-kVp protocol, while decreasing more image noise compared with the 80-kVp protocol with HIR.
Optimization of a secondary VOI protocol for lung imaging in a clinical CT scanner.
Larsen, Thomas C; Gopalakrishnan, Vissagan; Yao, Jianhua; Nguyen, Catherine P; Chen, Marcus Y; Moss, Joel; Wen, Han
2018-05-21
We present a solution to meet an unmet clinical need of an in-situ "close look" at a pulmonary nodule or at the margins of a pulmonary cyst revealed by a primary (screening) chest CT while the patient is still in the scanner. We first evaluated options available on current whole-body CT scanners for high resolution screening scans, including ROI reconstruction of the primary scan data and HRCT, but found them to have insufficient SNR in lung tissue or discontinuous slice coverage. Within the capabilities of current clinical CT systems, we opted for the solution of a secondary, volume-of-interest (VOI) protocol where the radiation dose is focused into a short-beam axial scan at the z position of interest, combined with a small-FOV reconstruction at the xy position of interest. The objective of this work was to design a VOI protocol that is optimized for targeted lung imaging in a clinical whole-body CT system. Using a chest phantom containing a lung-mimicking foam insert with a simulated cyst, we identified the appropriate scan mode and optimized both the scan and recon parameters. The VOI protocol yielded 3.2 times the texture amplitude-to-noise ratio in the lung-mimicking foam when compared to the standard chest CT, and 8.4 times the texture difference between the lung mimicking and reference foams. It improved details of the wall of the simulated cyst and better resolution in a line-pair insert. The Effective Dose of the secondary VOI protocol was 42% on average and up to 100% in the worst-case scenario of VOI positioning relative to the standard chest CT. The optimized protocol will be used to obtain detailed CT textures of pulmonary lesions, which are biomarkers for the type and stage of lung diseases. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.
Strumwasser, Aaron; Chong, Vincent; Chu, Eveline; Victorino, Gregory P
2016-09-01
The precise role of thoracic CT in penetrating chest trauma remains to be defined. We hypothesized that thoracic CT effectively screens hemodynamically normal patients with penetrating thoracic trauma to surgery vs. expectant management (NOM). A ten-year review of all penetrating torso cases was retrospectively analyzed from our urban University-based trauma center. We included hemodynamically normal patients (systolic blood pressure ≥90) with penetrating chest injuries that underwent screening thoracic CT. Hemodynamically unstable patients and diaphragmatic injuries were excluded. The sensitivity, specificity, positive predictive value and negative predictive value were calculated. A total of 212 patients (mean injury severity score=24, Abbreviated Injury Score for Chest=3.9) met inclusion criteria. Of these, 84.3% underwent NOM, 9.1% necessitated abdominal exploration, 6.6% underwent exploration for retained hemothorax/empyema, 6.6% underwent immediate thoracic exploration for significant injuries on chest CT, and 1.0% underwent delayed thoracic exploration for missed injuries. Thoracic CT had a sensitivity of 82%, specificity of 99%, positive predictive value of 90%, a negative predictive value of 99%, and an accuracy of 99% in predicting surgery vs. NOM. Thoracic CT has a negative predictive value of 99% in triaging hemodynamically normal patients with penetrating chest trauma. Screening thoracic CT successfully excludes surgery in patients with non-significant radiologic findings. Copyright © 2016. Published by Elsevier Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fujii, K; UCLA School of Medicine, Los Angeles, CA; Bostani, M
Purpose: The aim of this study was to collect CT dose index data from adult head exams to establish benchmarks based on either: (a) values pooled from all head exams or (b) values for specific protocols. One part of this was to investigate differences in scan frequency and CT dose index data for inpatients versus outpatients. Methods: We collected CT dose index data (CTDIvol) from adult head CT examinations performed at our medical facilities from Jan 1st to Dec 31th, 2014. Four of these scanners were used for inpatients, the other five were used for outpatients. All scanners used Tubemore » Current Modulation. We used X-ray dose management software to mine dose index data and evaluate CTDIvol for 15807 inpatients and 4263 outpatients undergoing Routine Brain, Sinus, Facial/Mandible, Temporal Bone, CTA Brain and CTA Brain-Neck protocols, and combined across all protocols. Results: For inpatients, Routine Brain series represented 84% of total scans performed. For outpatients, Sinus scans represented the largest fraction (36%). The CTDIvol (mean ± SD) across all head protocols was 39 ± 30 mGy (min-max: 3.3–540 mGy). The CTDIvol for Routine Brain was 51 ± 6.2 mGy (min-max: 36–84 mGy). The values for Sinus were 24 ± 3.2 mGy (min-max: 13–44 mGy) and for Facial/Mandible were 22 ± 4.3 mGy (min-max: 14–46 mGy). The mean CTDIvol for inpatients and outpatients was similar across protocols with one exception (CTA Brain-Neck). Conclusion: There is substantial dose variation when results from all protocols are pooled together; this is primarily a function of the differences in technical factors of the protocols themselves. When protocols are analyzed separately, there is much less variability. While analyzing pooled data affords some utility, reviewing protocols segregated by clinical indication provides greater opportunity for optimization and establishing useful benchmarks.« less
McColl, Tamara; Gatien, Mathieu; Calder, Lisa; Yadav, Krishan; Tam, Ryan; Ong, Melody; Taljaard, Monica; Stiell, Ian
2017-03-01
In 2008-2009, the Canadian Institute for Health Information reported over 30,000 cases of sepsis hospitalizations in Canada, an increase of almost 4,000 from 2005. Mortality rates from severe sepsis and septic shock continue to remain greater than 30% in Canada and are significantly higher than other critical conditions treated in the emergency department (ED). Our group formed a multidisciplinary sepsis committee, conducted an ED process of care analysis, and developed a quality improvement protocol. The objective of this study was to evaluate the effects of this sepsis management bundle on patient mortality. This before and after study was conducted in two large Canadian tertiary care EDs and included adult patients with suspected severe infection that met at least two systemic inflammatory response syndrome (SIRS) criteria. We studied the implementation of a sepsis bundle including triage flagging, RN medical directive, education campaign, and a modified sepsis protocol. The primary outcomes were 30-day all-cause mortality and sepsis protocol use. We included a total of 167 and 185 patients in the pre- and post-intervention analysis, respectively. Compared to the pre-intervention group, mortality was significantly lower in the post-intervention group (30.7% versus 17.3%; absolute difference, 13.4%; 95% CI 9.8-17.0; p=0.006). There was also a higher rate of sepsis protocol use in the post-intervention group (20.3% versus 80.5%, absolute difference 60.2%; 95% CI 55.1-65.3; p<0.001). Additionally, we found shorter time-intervals from triage to MD assessment, fluid resuscitation, and antibiotic administration as well as lower rates of vasopressor requirements and ICU admission. Interpretation The implementation of our multidisciplinary ED sepsis bundle, including improved early identification and protocolized medical care, was associated with improved time to achieve key therapeutic interventions and a reduction in 30-day mortality. Similar low-cost initiatives could be implemented in other EDs to potentially improve outcomes for this high-risk group of patients.
Satterthwaite, Peter S; Atkinson, Carol J
2012-02-01
This report analyses the impact of reverse triage, as described by Kelen, to rapidly assess the need for continuing inpatient care and to expedite patient discharge to create surge capacity for disaster victims. The Royal Darwin Hospital was asked to take up to 30 casualties suffering from blast injuries from a boat carrying asylum seekers that had exploded 840 km west of Darwin. The hospital was full, with a backlog of cases awaiting admission in the emergency department. The Disaster Response Team convened at 10:00 to develop the surge capacity to admit up to 30 casualties. By 14:00, 56 beds (16% of capacity) were predicted to be available by 18:00. The special circumstances of a disaster enabled staff to suspend their usual activities and place a priority on triaging inpatients' suitability for discharge. The External Disaster Plan was activated and response protocols were followed. Normal elective activity was suspended. Multidisciplinary teams immediately assessed patients and completed the necessary clinical and administrative requirements to discharge them quickly. As per the Plan there was increased use of community care options: respite nursing home beds and community nursing services. Through a combination of cancellation of all planned admissions, discharging 19 patients at least 1 day earlier than planned and discharging all patients earlier in the day surge capacity was made available in Royal Darwin Hospital to accommodate blast victims. Notably, reverse triage resulted in no increase in clinical risk with only one patient who was discharged early returning for further treatment.
NASA Astrophysics Data System (ADS)
Gordon, Peter R.; Sephton, Mark A.
2016-11-01
Returning samples from Mars will require an effective method to assess and select the highest-priority geological materials. The ideal instrument for sample triage would be simple in operation, limited in its demand for resources, and rich in produced diagnostic information. Pyrolysis-Fourier infrared spectroscopy (pyrolysis-FTIR) is a potentially attractive triage instrument that considers both the past habitability of the sample depositional environment and the presence of organic matter that may reflect actual habitation. An important consideration for triage protocols is the sensitivity of the instrumental method. Experimental data indicate pyrolysis-FTIR sensitivities for organic matter at the tens of parts per million level. The mineral matrix in which the organic matter is hosted also has an influence on organic detection. To provide an insight into matrix effects, we mixed well-characterized organic matter with a variety of dry minerals, to represent the various inorganic matrices of Mars samples, prior to analysis. During pyrolysis-FTIR, serpentinites analogous to those on Mars indicative of the Phyllocian Era led to no negative effects on organic matter detection; sulfates analogous to those of the Theiikian Era led, in some instances, to the combustion of organic matter; and palagonites, which may represent samples from the Siderikian Era, led, in some instances, to the chlorination of organic matter. Any negative consequences brought about by these mineral effects can be mitigated by the correct choice of thermal extraction temperature. Our results offer an improved understanding of how pyrolysis-FTIR can perform during sample triage on Mars.
Lewis, Thomas L; Fothergill, Rachael T; Karthikesalingam, Alan
2016-10-24
Rupture of an abdominal aortic aneurysm (rAAA) carries a considerable mortality rate and is often fatal. rAAA can be treated through open or endovascular surgical intervention and it is possible that more rapid access to definitive intervention might be a key aspect of improving mortality for rAAA. Diagnosis is not always straightforward with up to 42% of rAAA initially misdiagnosed, introducing potentially harmful delay. There is a need for an effective clinical decision support tool for accurate prehospital diagnosis and triage to enable transfer to an appropriate centre. Prospective multicentre observational study assessing the diagnostic accuracy of a prehospital smartphone triage tool for detection of rAAA. The study will be conducted across London in conjunction with London Ambulance Service (LAS). A logistic score predicting the risk of rAAA by assessing ten key parameters was developed and retrospectively validated through logistic regression analysis of ambulance records and Hospital Episode Statistics data for 2200 patients from 2005 to 2010. The triage tool is integrated into a secure mobile app for major smartphone platforms. Key parameters collected from the app will be retrospectively matched with final hospital discharge diagnosis for each patient encounter. The primary outcome is to assess the sensitivity, specificity and positive predictive value of the rAAA triage tool logistic score in prospective use as a mob app for prehospital ambulance clinicians. Data collection started in November 2014 and the study will recruit a minimum of 1150 non-consecutive patients over a time period of 2 years. Full ethical approval has been gained for this study. The results of this study will be disseminated in peer-reviewed publications, and international/national presentations. CPMS 16459; pre-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Ben-Shlomo, A; Cohen, D; Bruckheimer, E; Bachar, G N; Konstantinovsky, R; Birk, E; Atar, E
2016-05-01
To compare the effective doses of needle biopsies based on dose measurements and simulations using adult and pediatric phantoms, between cone beam c-arm CT (CBCT) and CT. Effective doses were calculated and compared based on measurements and Monte Carlo simulations of CT- and CBCT-guided biopsy procedures of the lungs, liver, and kidney using pediatric and adult phantoms. The effective doses for pediatric and adult phantoms, using our standard protocols for upper, middle and lower lungs, liver, and kidney biopsies, were significantly lower under CBCT guidance than CT. The average effective dose for a 5-year old for these five biopsies was 0.36 ± 0.05 mSv with the standard CBCT exposure protocols and 2.13 ± 0.26 mSv with CT. The adult average effective dose for the five biopsies was 1.63 ± 0.22 mSv with the standard CBCT protocols and 8.22 ± 1.02 mSv using CT. The CT effective dose was higher than CBCT protocols for child and adult phantoms by 803 and 590% for upper lung, 639 and 525% for mid-lung, and 461 and 251% for lower lung, respectively. Similarly, the effective dose was higher by 691 and 762% for liver and 513 and 608% for kidney biopsies. Based on measurements and simulations with pediatric and adult phantoms, radiation effective doses during image-guided needle biopsies of the lung, liver, and kidney are significantly lower with CBCT than with CT.
The early detection of antral malignancy in the postmaxillectomy patient
DOE Office of Scientific and Technical Information (OSTI.GOV)
Som, P.M.; Shugar, J.M.; Biller, H.F.
1982-05-01
A protocol was developed for the radiographic evaluation of the postmaxillectomy patient that called for a six- to eight-week postoperative, baseline computed tomography (CT) scan, followed by CT scans at four- to six-month intervals for at least three years. This protocol allowed for an early, more complete assessment of clinically discovered recurrences and the detection of clinically occult recurrences in three out of 18 patients who followed the protocol. The CT appearance of the normal partial and total maxillectomy is discussed, as well as the focal nodular soft-tissue findings suggestive of recurrent disease.
NASA Astrophysics Data System (ADS)
Mahmud, M. H.; Nordin, A. J.; Saad, F. F. Ahmad; Fattah Azman, A. Z.
2014-11-01
This study aims to estimate the radiation effective dose resulting from whole body fluorine-18 flourodeoxyglucose Positron Emission Tomography (18F-FDG PET) scanning as compared to conservative Computed Tomography (CT) techniques in evaluating oncology patients. We reviewed 19 oncology patients who underwent 18F-FDG PET/CT at our centre for cancer staging. Internal and external doses were estimated using radioactivity of injected FDG and volume CT Dose Index (CTDIvol), respectively with employment of the published and modified dose coefficients. The median differences of dose among the conservative CT and PET protocols were determined using Kruskal Wallis test with p < 0.05 considered as significant. The median (interquartile range, IQR) effective doses of non-contrasted CT, contrasted CT and PET scanning protocols were 7.50 (9.35) mSv, 9.76 (3.67) mSv and 6.30 (1.20) mSv, respectively, resulting in the total dose of 21.46 (8.58) mSv. Statistically significant difference was observed in the median effective dose between the three protocols (p < 0.01). The effective doses of whole body 18F-FDG PET technique may be effective the lowest amongst the conventional CT imaging techniques.
Nagayama, Y; Nakaura, T; Oda, S; Tsuji, A; Urata, J; Furusawa, M; Tanoue, S; Utsunomiya, D; Yamashita, Y
2018-02-01
To perform an intra-individual investigation of the usefulness of a contrast medium (CM) and radiation dose-reduction protocol using single-source computed tomography (CT) combined with 100 kVp and sinogram-affirmed iterative reconstruction (SAFIRE) for whole-body CT (WBCT; chest-abdomen-pelvis CT) in oncology patients. Forty-three oncology patients who had undergone WBCT under both 120 and 100 kVp protocols at different time points (mean interscan intervals: 98 days) were included retrospectively. The CM doses for the 120 and 100 kVp protocols were 600 and 480 mg iodine/kg, respectively; 120 kVp images were reconstructed with filtered back-projection (FBP), whereas 100 kVp images were reconstructed with FBP (100 kVp-F) and the SAFIRE (100 kVp-S). The size-specific dose estimate (SSDE), iodine load and image quality of each protocol were compared. The SSDE and iodine load of 100 kVp protocol were 34% and 21%, respectively, lower than of 120 kVp protocol (SSDE: 10.6±1.1 versus 16.1±1.8 mGy; iodine load: 24.8±4versus 31.5±5.5 g iodine, p<0.01). Contrast enhancement, objective image noise, contrast-to-noise-ratio, and visual score of 100 kVp-S were similar to or better than of 120 kVp protocol. Compared with the 120 kVp protocol, the combined use of 100 kVp and SAFIRE in WBCT for oncology assessment with an SSCT facilitated substantial reduction in the CM and radiation dose while maintaining image quality. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Radiation Dose Index of Renal Colic Protocol CT Studies in the United States
Lukasiewicz, Adam; Bhargavan-Chatfield, Mythreyi; Coombs, Laura; Ghita, Monica; Weinreb, Jeffrey; Gunabushanam, Gowthaman; Moore, Christopher L.
2016-01-01
Purpose To determine radiation dose indexes for computed tomography (CT) performed with renal colic protocols in the United States, including frequency of reduced-dose technique usage and any institutional-level factors associated with high or low dose indexes. Materials and Methods The Dose Imaging Registry (DIR) collects deidentified CT data, including examination type and dose indexes, for CT performed at participating institutions; thus, the DIR portion of the study was exempt from institutional review board approval and was HIPAA compliant. CT dose indexes were examined at the institutional level for CT performed with a renal colic protocol at institutions that contributed at least 10 studies to the registry as of January 2013. Additionally, patients undergoing CT for renal colic at a single institution (with institutional review board approval and informed consent from prospective subjects and waiver of consent from retrospective subjects) were studied to examine individual renal colic CT dose index patterns and explore relationships between patient habitus, demographics, and dose indexes. Descriptive statistics were used to analyze dose indexes, and linear regression and Spearman correlations were used to examine relationships between dose indexes and institutional factors. Results There were 49 903 renal colic protocol CT examinations conducted at 93 institutions between May 2011 and January 2013. Mean age ± standard deviation was 49 years ± 18, and 53.9% of patients were female. Institutions contributed a median of 268 (interquartile range, 77–699) CT studies. Overall mean institutional dose-length product (DLP) was 746 mGy · cm (effective dose, 11.2 mSv), with a range of 307–1497 mGy · cm (effective dose, 4.6–22.5 mSv) for mean DLPs. Only 2% of studies were conducted with a DLP of 200 mGy · cm or lower (a “reduced dose”) (effective dose, 3 mSv), and only 10% of institutions kept DLP at 400 mGy · cm (effective dose, 6 mSv) or less in at least 50% of patients. Conclusion Reduced-dose renal protocol CT is used infrequently in the United States. Mean dose index is higher than reported previously, and institutional variation is substantial. PMID:24484064
SU-G-IeP2-10: Lens Dose Reduction by Patient Position Modification During Neck CT Exams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mosher, E; Lee, C; Butman, J
Purpose: Irradiation of the lens during a neck CT may increase a patient’s risk of developing cataracts later in life. Radiologists and technologists at the National Institutes of Health Clinical Center (NIHCC) have developed new CT imaging protocols that include a reduction in scan range and modifying neck positioning using a head tilt. This study will evaluate the efficacy of this protocol in the reduction of lens dose. Methods: We retrieved CT images of five male patients who had two sets of CT images: before and after the implementation of the new protocol. The lens doses before the new protocolmore » were calculated using an in-house CT dose calculator, National Cancer Institute dosimetry system for CT (NCICT), where computational human phantoms with no head tilt are included. We also calculated the lens dose for the patient CT conducted after the new protocol by using an adult male computational phantom with the neck position deformed to match the angle of the head tilt. We also calculated the doses to other radiosensitive organs including the globes of the eye, brain, pituitary gland and salivary glands before and after head tilt. Results: Our dose calculations demonstrated that modifying neck position reduced dose to the lens by 89% on average (range: 86–96%). Globe, brain, pituitary and salivary gland doses also decreased by an average of 65% (51–95%), 38% (−8–66%), 34% (−43–84%) and 14% (13–14%), respectively. The new protocol resulted in a nearly ten-fold decrease in lens dose. Conclusion: The use of a head tilt and scan range reduction is an easy and effective method to reduce radiation exposure to the lens and other radiosensitive organs, while still allowing for the inclusion of critical neck structures in the CT image. We are expanding our study to a total of 10 males and 10 females.« less
Wang, Xiao-ting; Liu, Da-wei; Zhang, Hong-min; He, Huai-wu; Liu, Ye; Chai, Wen-zhao; Du, Wei
2012-12-01
To investigate the effect of the bedside lung ultrasound in emergency(BLUE)-plus lung ultrasound protocol on lung consolidation and atelectasis of critical patients. All patients who need to receive mechanical ventilation for more than 48 hours in ICU from June 2010 to December 2011 in Peking Union Medical College Hospital were included in the study. BLUE-plus and BLUE lung ultrasound, bedside X-ray, lung CT examination were performed on all patients at the same time. The condition of lung consolidation and atelectasis discovered by BLUE-plus lung ultrasound protocol was recorded and compared with bedside X-ray or lung CT. The difference in assessment of lung consolidation and atelectasis between BLUE-plus lung ultrasound protocol and BLUE protocol was compared. A total of 78 patients were finally enrolled in the study. The lung CT found 70 cases (89.74%) had different degrees of lung consolidation and atelectasis. The sensitivity, specificity and diagnostic accuracy of lung consolidation and atelectasis by the bedside chest X-ray were 31.29%, 75.00% and 38.46%, respectively. BLUE-plus lung ultrasound protocol found 68 cases with lung consolidation and atelectasis, and its sensitivity, specificity, and diagnostic accuracy were 95.71%, 87.50% and 94.87%, respectively, which were significantly higher than those of lung CT. BLUE protocol found 48 cases of lung consolidation and atelectasis, and its sensitivity, specificity, and diagnostic accuracy were 65.71%, 75.00% and 66.67%, respectively. The position of lung consolidation and atelectasis which hadn't been found by BLUE protocol was mainly proved to be located in the basement of lung by lung CT. The incidence of lung consolidation and atelectasis in critical patients who received mechanical ventilation is high. The BLUE-plus lung ultrasound protocol has a relatively higher sensitivity, specificity and diagnostic accuracy for consolidation and atelectasis, which can find majority of consolidation and atelectasis. As BLUE-plus lung ultrasound is a bedside noninvasive method allowing immediate assessment of most lung consolidation and atelectasis, it will be likely the alternative of the CT and play a key role in assessment of lung consolidation and atelectasis.
Data-driven CT protocol review and management—experience from a large academic hospital.
Zhang, Da; Savage, Cristy A; Li, Xinhua; Liu, Bob
2015-03-01
Protocol review plays a critical role in CT quality assurance, but large numbers of protocols and inconsistent protocol names on scanners and in exam records make thorough protocol review formidable. In this investigation, we report on a data-driven cataloging process that can be used to assist in the reviewing and management of CT protocols. We collected lists of scanner protocols, as well as 18 months of recent exam records, for 10 clinical scanners. We developed computer algorithms to automatically deconstruct the protocol names on the scanner and in the exam records into core names and descriptive components. Based on the core names, we were able to group the scanner protocols into a much smaller set of "core protocols," and to easily link exam records with the scanner protocols. We calculated the percentage of usage for each core protocol, from which the most heavily used protocols were identified. From the percentage-of-usage data, we found that, on average, 18, 33, and 49 core protocols per scanner covered 80%, 90%, and 95%, respectively, of all exams. These numbers are one order of magnitude smaller than the typical numbers of protocols that are loaded on a scanner (200-300, as reported in the literature). Duplicated, outdated, and rarely used protocols on the scanners were easily pinpointed in the cataloging process. The data-driven cataloging process can facilitate the task of protocol review. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmid, Gebhard; Schmitz, Alexander; Borchardt, Dieter
The objective of this study was to compare the effective radiation dose of perineural and epidural injections of the lumbar spine under computed tomography (CT) or fluoroscopic guidance with respect to dose-reduced protocols. We assessed the radiation dose with an Alderson Rando phantom at the lumbar segment L4/5 using 29 thermoluminescence dosimeters. Based on our clinical experience, 4-10 CT scans and 1-min fluoroscopy are appropriate. Effective doses were calculated for CT for a routine lumbar spine protocol and for maximum dose reduction; as well as for fluoroscopy in a continuous and a pulsed mode (3-15 pulses/s). Effective doses under CTmore » guidance were 1.51 mSv for 4 scans and 3.53 mSv for 10 scans using a standard protocol and 0.22 mSv and 0.43 mSv for the low-dose protocol. In continuous mode, the effective doses ranged from 0.43 to 1.25 mSv for 1-3 min of fluoroscopy. Using 1 min of pulsed fluoroscopy, the effective dose was less than 0.1 mSv for 3 pulses/s. A consequent low-dose CT protocol reduces the effective dose compared to a standard lumbar spine protocol by more than 85%. The latter dose might be expected when applying about 1 min of continuous fluoroscopy for guidance. A pulsed mode further reduces the effective dose of fluoroscopy by 80-90%.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suckling, Tara; Smith, Tony; Reed, Warren
2013-06-15
Optimal arterial opacification is crucial in imaging the pulmonary arteries using computed tomography (CT). This poses the challenge of precisely timing data acquisition to coincide with the transit of the contrast bolus through the pulmonary vasculature. The aim of this quality assurance exercise was to investigate if a change in CT pulmonary angiography (CTPA) scanning protocol resulted in improved opacification of the pulmonary arteries. Comparison was made between the smart prep protocol (SPP) and the test bolus protocol (TBP) for opacification in the pulmonary trunk. A total of 160 CTPA examinations (80 using each protocol) performed between January 2010 andmore » February 2011 were assessed retrospectively. CT attenuation coefficients were measured in Hounsfield Units (HU) using regions of interest at the level of the pulmonary trunk. The average pixel value, standard deviation (SD), maximum, and minimum were recorded. For each of these variables a mean value was then calculated and compared for these two CTPA protocols. Minimum opacification of 200 HU was achieved in 98% of the TBP sample but only 90% of the SPP sample. The average CT attenuation over the pulmonary trunk for the SPP was 329 (SD = ±21) HU, whereas for the TBP it was 396 (SD = ±22) HU (P = 0.0017). The TBP also recorded higher maximum (P = 0.0024) and minimum (P = 0.0039) levels of opacification. This study has found that a TBP resulted in significantly better opacification of the pulmonary trunk than the SPP.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Driscoll, B.; Keller, H.; Jaffray, D.
2013-08-15
Purpose: Credentialing can have an impact on whether or not a clinical trial produces useful quality data that is comparable between various institutions and scanners. With the recent increase of dynamic contrast enhanced-computed tomography (DCE-CT) usage as a companion biomarker in clinical trials, effective quality assurance, and control methods are required to ensure there is minimal deviation in the results between different scanners and protocols at various institutions. This paper attempts to address this problem by utilizing a dynamic flow imaging phantom to develop and evaluate a DCE-CT quality assurance (QA) protocol.Methods: A previously designed flow phantom, capable of producingmore » predictable and reproducible time concentration curves from contrast injection was fully validated and then utilized to design a DCE-CT QA protocol. The QA protocol involved a set of quantitative metrics including injected and total mass error, as well as goodness of fit comparison to the known truth concentration curves. An additional region of interest (ROI) sensitivity analysis was also developed to provide additional details on intrascanner variability and determine appropriate ROI sizes for quantitative analysis. Both the QA protocol and ROI sensitivity analysis were utilized to test variations in DCE-CT results using different imaging parameters (tube voltage and current) as well as alternate reconstruction methods and imaging techniques. The developed QA protocol and ROI sensitivity analysis was then applied at three institutions that were part of clinical trial involving DCE-CT and results were compared.Results: The inherent specificity of robustness of the phantom was determined through calculation of the total intraday variability and determined to be less than 2.2 ± 1.1% (total calculated output contrast mass error) with a goodness of fit (R{sup 2}) of greater than 0.99 ± 0.0035 (n= 10). The DCE-CT QA protocol was capable of detecting significant deviations from the expected phantom result when scanning at low mAs and low kVp in terms of quantitative metrics (Injected Mass Error 15.4%), goodness of fit (R{sup 2}) of 0.91, and ROI sensitivity (increase in minimum input function ROI radius by 146 ± 86%). These tests also confirmed that the ASIR reconstruction process was beneficial in reducing noise without substantially increasing partial volume effects and that vendor specific modes (e.g., axial shuttle) did not significantly affect the phantom results. The phantom and QA protocol were finally able to quickly (<90 min) and successfully validate the DCE-CT imaging protocol utilized at the three separate institutions of a multicenter clinical trial; thereby enhancing the confidence in the patient data collected.Conclusions: A DCE QA protocol was developed that, in combination with a dynamic multimodality flow phantom, allows the intrascanner variability to be separated from other sources of variability such as the impact of injection protocol and ROI selection. This provides a valuable resource that can be utilized at various clinical trial institutions to test conformance with imaging protocols and accuracy requirements as well as ensure that the scanners are performing as expected for dynamic scans.« less
Efficacy of a two-tiered trauma team activation protocol in a Norwegian trauma centre.
Rehn, M; Lossius, H M; Tjosevik, K E; Vetrhus, M; Østebø, O; Eken, T
2012-02-01
A registry-based analysis revealed imprecise informal one-tiered trauma team activation (TTA) in a primary trauma centre. A two-tiered TTA protocol was introduced and analysed to examine its impact on triage precision and resource utilization. Interhospital transfers and patients admitted by non-healthcare personnel were excluded. Undertriage was defined as the fraction of major trauma victims (New Injury Severity Score over 15) admitted without TTA. Overtriage was the fraction of TTA without major trauma. Of 1812 patients, 768 had major trauma. Overall undertriage was reduced from 28·4 to 19·1 per cent (P < 0·001) after system revision. Overall overtriage increased from 61·5 to 71·6 per cent, whereas the mean number of skilled hours spent per overtriaged patient was reduced from 6·5 to 3·5 (P < 0·001) and the number of skilled hours spent per major trauma victim was reduced from 7·4 to 7·1 (P < 0·001). Increasing age increased risk for undertriage and decreased risk for overtriage. Falls increased risk for undertriage and decreased risk for overtriage, whereas motor vehicle-related accidents showed the opposite effects. Patients triaged to a prehospital response involving an anaesthetist had less chance of both undertriage and overtriage. A two-tiered TTA protocol was associated with reduced undertriage and increased overtriage, while trauma team resource consumption was reduced. NCT00876564 (http://www.clinicaltrials.gov). Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.
Woods, Brenda; Lennard, Chris; Kirkbride, K Paul; Robertson, James
2016-05-01
In the past, forensic soil examination was a routine aspect of forensic trace evidence examinations. The apparent need for soil examinations then went through a period of decline and with it the capability of many forensic laboratories to carry out soil examinations. In more recent years, interest in soil examinations has been renewed due-at least in part-to soil examinations contributing to some high profile investigations. However, much of this renewed interest has been in organisations with a primary interest in soil and geology rather than forensic science. We argue the need to reinstate soil examinations as a trace evidence sub-discipline within forensic science laboratories and present a pathway to support this aim. An examination procedure is proposed that includes: (i) appropriate sample collection and storage by qualified crime scene examiners; (ii) exclusionary soil examinations by trace evidence scientists within a forensic science laboratory; (iii) inclusionary soil examinations by trace evidence scientists within a forensic science laboratory; and (iv) higher-level examination of soils by specialist soil scientists and palynologists. Soil examinations conducted by trace evidence scientists will be facilitated if the examinations are conducted using the instrumentation routinely used by these examiners. Hence, the proposed examination protocol incorporates instrumentation in routine use in a forensic trace evidence laboratory. Finally, we report on an Australian soil scene variability study and a blind trial that demonstrate the utility of the proposed protocol for the effective triage and management of soil samples by forensic laboratories. Crown Copyright © 2016. Published by Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Noid, G; Tai, A; Liu, Y
Purpose: It is desirable to increase CT soft-tissue contrast to improve delineation of tumor target and/or surrounding organs at risk (OAR) in RT planning and delivery guidance. The purpose of this work is to investigate the use of monoenergetic decompositions obtained from dual energy (DE) CT to improve soft-tissue contrast. Methods: CT data were acquired for 5 prostate and 5 pancreas patients and a phantom with a CT Scanner (Definition AS Open, Siemens) using both sequential DE protocols and standard protocols. For the DE protocols, the scanner rapidly performs two acquisitions at 80 kVp and 140 kVp. The CT numbersmore » of soft tissue inserts in the phantom (CTED/Gammex) were measured across the spectrum of available monoenergetic decompositions (40 to 140 keV) and compared to the standard protocol (120 kVp, 0.6 pitch, 18 mGy CTDIvol). Contrast, defined as the difference in the average CT number between target and OAR, was measured for all subjects and compared between the DE and standard protocols. Results: Mono-energetic decompositions of the phantom demonstrate an enhancement of soft-tissue contrast as the energy is decreased. For instance, relative to the 120 kVp scans the Liver ED insert increased in CT number by 25 HU while the adipose ED insert decreased by 50 HU. The lowest energy decompositions featured the highest contrast between target and OAR. For every patient, the contrast increased by decomposing at 40 keV. The average increase in contrast relative to a 120 kVp scan for prostate patients at 40 keV was 25.05±17.28 HU while for pancreas patients it was 19.21±17.39 HU. Conclusion: Low energy monoenergetic decompositions from dual-energy CT substantially increase soft-tissue contrast. At the lowest achievable monoenergetic decompositions the maximum soft-tissue contrast is achieved and the delineation of target and OAR is improved. Thus it is beneficial to use DECT in radiation oncology. Supported by Siemens.« less
Advances in Imaging and Management Trends of Traumatic Aortic Injuries.
Nagpal, Prashant; Mullan, Brian F; Sen, Indrani; Saboo, Sachin S; Khandelwal, Ashish
2017-05-01
Acute traumatic aortic injury (ATAI) is a life-threatening injury. CT is the imaging tool of choice, and the knowledge of direct and indirect signs of injury, grading system, and current management protocol helps the emergency radiologist to better identify and classify the injury and provide additional details that can impact management options. Newer dual-source CT technology with ultrafast acquisition speed has also influenced the appropriate protocol for imaging in patients with suspected ATAI. This review highlights the imaging protocol in patients with blunt trauma, CT appearance and grading systems of ATAI, management options, and the role of the multidisciplinary team in the management of these patients. We also briefly review the current literature on the definition, treatment, and follow-up protocol in patients with minimal aortic injury.
Fox, Anne-Marie V; Kedgley, Angela E; Lalone, Emily A; Johnson, James A; Athwal, George S; Jenkyn, Thomas R
2011-11-10
Standard, beaded radiostereometric analysis (RSA) and markerless RSA often use computed tomography (CT) scans to create three-dimensional (3D) bone models. However, ethical concerns exist due to risks associated with CT radiation exposure. Therefore, the aim of this study was to investigate the effect of decreasing CT dosage on RSA accuracy. Four cadaveric shoulder specimens were scanned using a normal-dose CT protocol and two low-dose protocols, where the dosage was decreased by 89% and 98%. 3D computer models of the humerus and scapula were created using each CT protocol. Bi-planar fluoroscopy was used to image five different static glenohumeral positions and two dynamic glenohumeral movements, of which a total of five static and four dynamic poses were selected for analysis. For standard RSA, negligible differences were found in bead (0.21±0.31mm) and bony landmark (2.31±1.90mm) locations when the CT dosage was decreased by 98% (p-values>0.167). For markerless RSA kinematic results, excellent agreement was found between the normal-dose and lowest-dose protocol, with all Spearman rank correlation coefficients greater than 0.95. Average root mean squared errors of 1.04±0.68mm and 2.42±0.81° were also found at this reduced dosage for static positions. In summary, CT dosage can be markedly reduced when performing shoulder RSA to minimize the risks of radiation exposure. Standard RSA accuracy was negligibly affected by the 98% CT dose reduction and for markerless RSA, the benefits of decreasing CT dosage to the subject outweigh the introduced errors. Copyright © 2011 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ben-Shlomo, A.; Cohen, D.; Bruckheimer, E.
PurposeTo compare the effective doses of needle biopsies based on dose measurements and simulations using adult and pediatric phantoms, between cone beam c-arm CT (CBCT) and CT.MethodEffective doses were calculated and compared based on measurements and Monte Carlo simulations of CT- and CBCT-guided biopsy procedures of the lungs, liver, and kidney using pediatric and adult phantoms.ResultsThe effective doses for pediatric and adult phantoms, using our standard protocols for upper, middle and lower lungs, liver, and kidney biopsies, were significantly lower under CBCT guidance than CT. The average effective dose for a 5-year old for these five biopsies was 0.36 ± 0.05 mSv withmore » the standard CBCT exposure protocols and 2.13 ± 0.26 mSv with CT. The adult average effective dose for the five biopsies was 1.63 ± 0.22 mSv with the standard CBCT protocols and 8.22 ± 1.02 mSv using CT. The CT effective dose was higher than CBCT protocols for child and adult phantoms by 803 and 590 % for upper lung, 639 and 525 % for mid-lung, and 461 and 251 % for lower lung, respectively. Similarly, the effective dose was higher by 691 and 762 % for liver and 513 and 608 % for kidney biopsies.ConclusionsBased on measurements and simulations with pediatric and adult phantoms, radiation effective doses during image-guided needle biopsies of the lung, liver, and kidney are significantly lower with CBCT than with CT.« less
An Innovative Model to Predict Pediatric Emergency Department Return Visits.
Bergese, Ilaria; Frigerio, Simona; Clari, Marco; Castagno, Emanuele; De Clemente, Antonietta; Ponticelli, Elena; Scavino, Enrica; Berchialla, Paola
2016-10-06
Return visit (RV) to the emergency department (ED) is considered a benchmarking clinical indicator for health care quality. The purpose of this study was to develop a predictive model for early readmission risk in pediatric EDs comparing the performances of 2 learning machine algorithms. A retrospective study based on all children younger than 15 years spontaneously returning within 120 hours after discharge was conducted in an Italian university children's hospital between October 2012 and April 2013. Two predictive models, artificial neural network (ANN) and classification tree (CT), were used. Accuracy, specificity, and sensitivity were assessed. A total of 28,341 patient records were evaluated. Among them, 626 patients returned to the ED within 120 hours after their initial visit. Comparing ANN and CT, our analysis has shown that CT is the best model to predict RVs. The CT model showed an overall accuracy of 81%, slightly lower than the one achieved by the ANN (91.3%), but CT outperformed ANN with regard to sensitivity (79.8% vs 6.9%, respectively). The specificity was similar for the 2 models (CT, 97% vs ANN, 98.3%). In addition, the time of arrival and discharge along with the priority code assigned in triage, age, and diagnosis play a pivotal role to identify patients at high risk of RVs. These models provide a promising predictive tool for supporting the ED staff in preventing unnecessary RVs.
Lv, Peijie; Liu, Jie; Chai, Yaru; Yan, Xiaopeng; Gao, Jianbo; Dong, Junqiang
2017-01-01
To evaluate the feasibility, image quality, and radiation dose of automatic spectral imaging protocol selection (ASIS) and adaptive statistical iterative reconstruction (ASIR) with reduced contrast agent dose in abdominal multiphase CT. One hundred and sixty patients were randomly divided into two scan protocols (n = 80 each; protocol A, 120 kVp/450 mgI/kg, filtered back projection algorithm (FBP); protocol B, spectral CT imaging with ASIS and 40 to 70 keV monochromatic images generated per 300 mgI/kg, ASIR algorithm. Quantitative parameters (image noise and contrast-to-noise ratios [CNRs]) and qualitative visual parameters (image noise, small structures, organ enhancement, and overall image quality) were compared. Monochromatic images at 50 keV and 60 keV provided similar or lower image noise, but higher contrast and overall image quality as compared with 120-kVp images. Despite the higher image noise, 40-keV images showed similar overall image quality compared to 120-kVp images. Radiation dose did not differ between the two protocols, while contrast agent dose in protocol B was reduced by 33 %. Application of ASIR and ASIS to monochromatic imaging from 40 to 60 keV allowed contrast agent dose reduction with adequate image quality and without increasing radiation dose compared to 120 kVp with FBP. • Automatic spectral imaging protocol selection provides appropriate scan protocols. • Abdominal CT is feasible using spectral imaging and 300 mgI/kg contrast agent. • 50-keV monochromatic images with 50 % ASIR provide optimal image quality.
Dos Santos, Denise Takehana; Costa e Silva, Adriana Paula Andrade; Vannier, Michael Walter; Cavalcanti, Marcelo Gusmão Paraiso
2004-12-01
The purpose of this study was to demonstrate the sensitivity and specificity of multislice computerized tomography (CT) for diagnosis of maxillofacial fractures following specific protocols using an independent workstation. The study population consisted of 56 patients with maxillofacial fractures who were submitted to a multislice CT. The original data were transferred to an independent workstation using volumetric imaging software to generate axial images and simultaneous multiplanar (MPR) and 3-dimensional (3D-CT) volume rendering reconstructed images. The images were then processed and interpreted by 2 examiners using the following protocols independently of each other: axial, MPR/axial, 3D-CT images, and the association of axial/MPR/3D images. The clinical/surgical findings were considered the gold standard corroborating the diagnosis of the fractures and their anatomic localization. The statistical analysis was carried out using validity and chi-squared tests. The association of axial/MPR/3D images indicated a higher sensitivity (range 95.8%) and specificity (range 99%) than the other methods regarding the analysis of all regions. CT imaging demonstrated high specificity and sensitivity for maxillofacial fractures. The association of axial/MPR/3D-CT images added important information in relationship to other CT protocols.
Bischel, Alexander; Stratis, Andreas; Kakar, Apoorv; Bosmans, Hilde; Jacobs, Reinhilde; Gassner, Eva-Maria; Puelacher, Wolfgang; Pauwels, Ruben
2016-01-01
Objective: The aim of this study was to evaluate whether application of ultralow dose protocols and iterative reconstruction technology (IRT) influence quantitative Hounsfield units (HUs) and contrast-to-noise ratio (CNR) in dentomaxillofacial CT imaging. Methods: A phantom with inserts of five types of materials was scanned using protocols for (a) a clinical reference for navigated surgery (CT dose index volume 36.58 mGy), (b) low-dose sinus imaging (18.28 mGy) and (c) four ultralow dose imaging (4.14, 2.63, 0.99 and 0.53 mGy). All images were reconstructed using: (i) filtered back projection (FBP); (ii) IRT: adaptive statistical iterative reconstruction-50 (ASIR-50), ASIR-100 and model-based iterative reconstruction (MBIR); and (iii) standard (std) and bone kernel. Mean HU, CNR and average HU error after recalibration were determined. Each combination of protocols was compared using Friedman analysis of variance, followed by Dunn's multiple comparison test. Results: Pearson's sample correlation coefficients were all >0.99. Ultralow dose protocols using FBP showed errors of up to 273 HU. Std kernels had less HU variability than bone kernels. MBIR reduced the error value for the lowest dose protocol to 138 HU and retained the highest relative CNR. ASIR could not demonstrate significant advantages over FBP. Conclusions: Considering a potential dose reduction as low as 1.5% of a std protocol, ultralow dose protocols and IRT should be further tested for clinical dentomaxillofacial CT imaging. Advances in knowledge: HU as a surrogate for bone density may vary significantly in CT ultralow dose imaging. However, use of std kernels and MBIR technology reduce HU error values and may retain the highest CNR. PMID:26859336
Physics of cardiac imaging with multiple-row detector CT.
Mahesh, Mahadevappa; Cody, Dianna D
2007-01-01
Cardiac imaging with multiple-row detector computed tomography (CT) has become possible due to rapid advances in CT technologies. Images with high temporal and spatial resolution can be obtained with multiple-row detector CT scanners; however, the radiation dose associated with cardiac imaging is high. Understanding the physics of cardiac imaging with multiple-row detector CT scanners allows optimization of cardiac CT protocols in terms of image quality and radiation dose. Knowledge of the trade-offs between various scan parameters that affect image quality--such as temporal resolution, spatial resolution, and pitch--is the key to optimized cardiac CT protocols, which can minimize the radiation risks associated with these studies. Factors affecting temporal resolution include gantry rotation time, acquisition mode, and reconstruction method; factors affecting spatial resolution include detector size and reconstruction interval. Cardiac CT has the potential to become a reliable tool for noninvasive diagnosis and prevention of cardiac and coronary artery disease. (c) RSNA, 2007.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christianson, O; Winslow, J; Samei, E
2014-06-15
Purpose: One of the principal challenges of clinical imaging is to achieve an ideal balance between image quality and radiation dose across multiple CT models. The number of scanners and protocols at large medical centers necessitates an automated quality assurance program to facilitate this objective. Therefore, the goal of this work was to implement an automated CT image quality and radiation dose monitoring program based on actual patient data and to use this program to assess consistency of protocols across CT scanner models. Methods: Patient CT scans are routed to a HIPPA compliant quality assurance server. CTDI, extracted using opticalmore » character recognition, and patient size, measured from the localizers, are used to calculate SSDE. A previously validated noise measurement algorithm determines the noise in uniform areas of the image across the scanned anatomy to generate a global noise level (GNL). Using this program, 2358 abdominopelvic scans acquired on three commercial CT scanners were analyzed. Median SSDE and GNL were compared across scanner models and trends in SSDE and GNL with patient size were used to determine the impact of differing automatic exposure control (AEC) algorithms. Results: There was a significant difference in both SSDE and GNL across scanner models (9–33% and 15–35% for SSDE and GNL, respectively). Adjusting all protocols to achieve the same image noise would reduce patient dose by 27–45% depending on scanner model. Additionally, differences in AEC methodologies across vendors resulted in disparate relationships of SSDE and GNL with patient size. Conclusion: The difference in noise across scanner models indicates that protocols are not optimally matched to achieve consistent image quality. Our results indicated substantial possibility for dose reduction while achieving more consistent image appearance. Finally, the difference in AEC methodologies suggests the need for size-specific CT protocols to minimize variability in image quality across CT vendors.« less
Ekins, Kylie; Morphet, Julia
2015-11-01
The Australasian Triage Scale aims to ensure that the triage category allocated, reflects the urgency with which the patient needs medical assistance. This is dependent on triage nurse accuracy in decision making. The Australasian Triage Scale also aims to facilitate triage decision consistency between individuals and organisations. Various studies have explored the accuracy and consistency of triage decisions throughout Australia, yet no studies have specifically focussed on triage decision making in rural health services. Further, no standard has been identified by which accuracy or consistency should be measured. Australian emergency departments are measured against a set of standard performance indicators, including time from triage to patient review, and patient length of stay. There are currently no performance indicators for triage consistency. An online questionnaire was developed to collect demographic data and measure triage accuracy and consistency. The questionnaire utilised previously validated triage scenarios.(1) Triage decision accuracy was measured, and consistency was compared by health site type using Fleiss' kappa. Forty-six triage nurses participated in this study. The accuracy of participants' triage decision-making decreased with each less urgent triage category. Post-graduate qualifications had no bearing on triage accuracy. There was no significant difference in the consistency of decision-making between paediatric and adult scenarios. Overall inter-rater agreement using Fleiss' kappa coefficient, was 0.4. This represents a fair-to-good level of inter-rater agreement. A standard definition of accuracy and consistency in triage nurse decision making is required. Inaccurate triage decisions can result in increased morbidity and mortality. It is recommended that emergency department performance indicator thresholds be utilised as a benchmark for national triage consistency. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.
Gordon, Peter R; Sephton, Mark A
2016-11-01
Returning samples from Mars will require an effective method to assess and select the highest-priority geological materials. The ideal instrument for sample triage would be simple in operation, limited in its demand for resources, and rich in produced diagnostic information. Pyrolysis-Fourier infrared spectroscopy (pyrolysis-FTIR) is a potentially attractive triage instrument that considers both the past habitability of the sample depositional environment and the presence of organic matter that may reflect actual habitation. An important consideration for triage protocols is the sensitivity of the instrumental method. Experimental data indicate pyrolysis-FTIR sensitivities for organic matter at the tens of parts per million level. The mineral matrix in which the organic matter is hosted also has an influence on organic detection. To provide an insight into matrix effects, we mixed well-characterized organic matter with a variety of dry minerals, to represent the various inorganic matrices of Mars samples, prior to analysis. During pyrolysis-FTIR, serpentinites analogous to those on Mars indicative of the Phyllocian Era led to no negative effects on organic matter detection; sulfates analogous to those of the Theiikian Era led, in some instances, to the combustion of organic matter; and palagonites, which may represent samples from the Siderikian Era, led, in some instances, to the chlorination of organic matter. Any negative consequences brought about by these mineral effects can be mitigated by the correct choice of thermal extraction temperature. Our results offer an improved understanding of how pyrolysis-FTIR can perform during sample triage on Mars. Key Words: Mars-Life-detection instruments-Search for Mars' organics-Biosignatures. Astrobiology 16, 831-845.
Gordon, Peter R.
2016-01-01
Abstract Returning samples from Mars will require an effective method to assess and select the highest-priority geological materials. The ideal instrument for sample triage would be simple in operation, limited in its demand for resources, and rich in produced diagnostic information. Pyrolysis–Fourier infrared spectroscopy (pyrolysis-FTIR) is a potentially attractive triage instrument that considers both the past habitability of the sample depositional environment and the presence of organic matter that may reflect actual habitation. An important consideration for triage protocols is the sensitivity of the instrumental method. Experimental data indicate pyrolysis-FTIR sensitivities for organic matter at the tens of parts per million level. The mineral matrix in which the organic matter is hosted also has an influence on organic detection. To provide an insight into matrix effects, we mixed well-characterized organic matter with a variety of dry minerals, to represent the various inorganic matrices of Mars samples, prior to analysis. During pyrolysis-FTIR, serpentinites analogous to those on Mars indicative of the Phyllocian Era led to no negative effects on organic matter detection; sulfates analogous to those of the Theiikian Era led, in some instances, to the combustion of organic matter; and palagonites, which may represent samples from the Siderikian Era, led, in some instances, to the chlorination of organic matter. Any negative consequences brought about by these mineral effects can be mitigated by the correct choice of thermal extraction temperature. Our results offer an improved understanding of how pyrolysis-FTIR can perform during sample triage on Mars. Key Words: Mars—Life-detection instruments—Search for Mars’ organics—Biosignatures. Astrobiology 16, 831–845. PMID:27870586
2014-01-01
Background and purpose It is difficult to evaluate glenoid component periprosthetic radiolucencies in total shoulder arthroplasties (TSAs) using plain radiographs. This study was performed to evaluate whether computed tomography (CT) using a specific patient position in the CT scanner provides a better method for assessing radiolucencies in TSA. Methods Following TSA, 11 patients were CT scanned in a lateral decubitus position with maximum forward flexion, which aligns the glenoid orientation with the axis of the CT scanner. Follow-up CT scanning is part of our routine patient care. Glenoid component periprosthetic lucency was assessed according to the Molé score and it was compared to routine plain radiographs by 5 observers. Results The protocol almost completely eliminated metal artifacts in the CT images and allowed accurate assessment of periprosthetic lucency of the glenoid fixation. Positioning of the patient within the CT scanner as described was possible for all 11 patients. A radiolucent line was identified in 54 of the 55 observed CT scans and osteolysis was identified in 25 observations. The average radiolucent line Molé score was 3.4 (SD 2.7) points with plain radiographs and 9.5 (SD 0.8) points with CT scans (p = 0.001). The mean intra-observer variance was lower in the CT scan group than in the plain radiograph group (p = 0.001). Interpretation The CT scan protocol we used is of clinical value in routine assessment of glenoid periprosthetic lucency after TSA. The technique improves the ability to detect and monitor radiolucent lines and, therefore, possibly implant loosening also. PMID:24286563
Kahn, Johannes; Kaul, David; Böning, Georg; Rotzinger, Roman; Freyhardt, Patrick; Schwabe, Philipp; Maurer, Martin H; Renz, Diane Miriam; Streitparth, Florian
2017-09-01
Purpose As a supra-regional level-I trauma center, we evaluated computed tomography (CT) acquisitions of polytraumatized patients for quality and dose optimization purposes. Adapted statistical iterative reconstruction [(AS)IR] levels, tube voltage reduction as well as a split-bolus contrast agent (CA) protocol were applied. Materials and Methods 61 patients were split into 3 different groups that differed with respect to tube voltage (120 - 140 kVp) and level of applied ASIR reconstruction (ASIR 20 - 50 %). The CT protocol included a native acquisition of the head followed by a single contrast-enhanced acquisition of the whole body (64-MSCT). CA (350 mg/ml iodine) was administered as a split bolus injection of 100 ml (2 ml/s), 20 ml NaCl (1 ml/s), 60 ml (4 ml/s), 40 ml NaCl (4 ml/s) with a scan delay of 85 s to detect injuries of both the arterial system and parenchymal organs in a single acquisition. Both the quantitative (SNR/CNR) and qualitative (5-point Likert scale) image quality was evaluated in parenchymal organs that are often injured in trauma patients. Radiation exposure was assessed. Results The use of IR combined with a reduction of tube voltage resulted in good qualitative and quantitative image quality and a significant reduction in radiation exposure of more than 40 % (DLP 1087 vs. 647 mGyxcm). Image quality could be improved due to a dedicated protocol that included different levels of IR adapted to different slice thicknesses, kernels and the examined area for the evaluation of head, lung, body and bone injury patterns. In synopsis of our results, we recommend the implementation of a polytrauma protocol with a tube voltage of 120 kVp and the following IR levels: cCT 5mm: ASIR 20; cCT 0.625 mm: ASIR 40; lung 2.5 mm: ASIR 30, body 5 mm: ASIR 40; body 1.25 mm: ASIR 50; body 0.625 mm: ASIR 0. Conclusion A dedicated adaptation of the CT trauma protocol (level of reduction of tube voltage and of IR) according to the examined body region (head, lung, body, bone) combined with a split bolus CA injection protocol allows for a high-quality CT examination and a relevant reduction of radiation exposure in the examination of polytraumatized patients Key Points · Dedicated adaption of the CT trauma protocol allows for an optimized examination.. · Different levels of iterative reconstruction, tube voltage and the CA injection protocol are crucial.. · A reduction of radiation exposure of more than 40 % with good image quality is possible.. Citation Format · Kahn J, Kaul D, Böning G et al. Quality and Dose Optimized CT Trauma Protocol - Recommendation from a University Level-I Trauma Center. Fortschr Röntgenstr 2017; 189: 844 - 854. © Georg Thieme Verlag KG Stuttgart · New York.
Kaasalainen, Touko; Palmu, Kirsi; Lampinen, Anniina; Reijonen, Vappu; Leikola, Junnu; Kivisaari, Riku; Kortesniemi, Mika
2015-09-01
Medical professionals need to exercise particular caution when developing CT scanning protocols for children who require multiple CT studies, such as those with craniosynostosis. To evaluate the utility of ultra-low-dose CT protocols with model-based iterative reconstruction techniques for craniosynostosis imaging. We scanned two pediatric anthropomorphic phantoms with a 64-slice CT scanner using different low-dose protocols for craniosynostosis. We measured organ doses in the head region with metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. Numerical simulations served to estimate organ and effective doses. We objectively and subjectively evaluated the quality of images produced by adaptive statistical iterative reconstruction (ASiR) 30%, ASiR 50% and Veo (all by GE Healthcare, Waukesha, WI). Image noise and contrast were determined for different tissues. Mean organ dose with the newborn phantom was decreased up to 83% compared to the routine protocol when using ultra-low-dose scanning settings. Similarly, for the 5-year phantom the greatest radiation dose reduction was 88%. The numerical simulations supported the findings with MOSFET measurements. The image quality remained adequate with Veo reconstruction, even at the lowest dose level. Craniosynostosis CT with model-based iterative reconstruction could be performed with a 20-μSv effective dose, corresponding to the radiation exposure of plain skull radiography, without compromising required image quality.
A concept for major incident triage: full-scaled simulation feasibility study.
Rehn, Marius; Andersen, Jan E; Vigerust, Trond; Krüger, Andreas J; Lossius, Hans M
2010-08-11
Efficient management of major incidents involves triage, treatment and transport. In the absence of a standardised interdisciplinary major incident management approach, the Norwegian Air Ambulance Foundation developed Interdisciplinary Emergency Service Cooperation Course (TAS). The TAS-program was established in 1998 and by 2009, approximately 15 500 emergency service professionals have participated in one of more than 500 no-cost courses. The TAS-triage concept is based on the established triage Sieve and Paediatric Triage Tape models but modified with slap-wrap reflective triage tags and paediatric triage stretchers. We evaluated the feasibility and accuracy of the TAS-triage concept in full-scale simulated major incidents. The learners participated in two standardised bus crash simulations: without and with competence of TAS-triage and access to TAS-triage equipment. The instructors calculated triage accuracy and measured time consumption while the learners participated in a self-reported before-after study. Each question was scored on a 7-point Likert scale with points labelled "Did not work" (1) through "Worked excellent" (7). Among the 93 (85%) participating emergency service professionals, 48% confirmed the existence of a major incident triage system in their service, whereas 27% had access to triage tags. The simulations without TAS-triage resulted in a mean over- and undertriage of 12%. When TAS-Triage was used, no mistriage was found. The average time from "scene secured to all patients triaged" was 22 minutes (range 15-32) without TAS-triage vs. 10 minutes (range 5-21) with TAS-triage. The participants replied to "How did interdisciplinary cooperation of triage work?" with mean 4,9 (95% CI 4,7-5,2) before the course vs. mean 5,8 (95% CI 5,6-6,0) after the course, p < 0,001. Our modified triage Sieve tool is feasible, time-efficient and accurate in allocating priority during simulated bus accidents and may serve as a candidate for a future national standard for major incident triage.
Advances in Imaging and Management Trends of Traumatic Aortic Injuries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nagpal, Prashant, E-mail: drprashantnagpal@gmail.com, E-mail: Prashant-nagpal@uiowa.edu; Mullan, Brian F.; Sen, Indrani
Acute traumatic aortic injury (ATAI) is a life-threatening injury. CT is the imaging tool of choice, and the knowledge of direct and indirect signs of injury, grading system, and current management protocol helps the emergency radiologist to better identify and classify the injury and provide additional details that can impact management options. Newer dual-source CT technology with ultrafast acquisition speed has also influenced the appropriate protocol for imaging in patients with suspected ATAI. This review highlights the imaging protocol in patients with blunt trauma, CT appearance and grading systems of ATAI, management options, and the role of the multidisciplinary teammore » in the management of these patients. We also briefly review the current literature on the definition, treatment, and follow-up protocol in patients with minimal aortic injury.« less
SU-F-207-16: CT Protocols Optimization Using Model Observer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tseng, H; Fan, J; Kupinski, M
2015-06-15
Purpose: To quantitatively evaluate the performance of different CT protocols using task-based measures of image quality. This work studies the task of size and the contrast estimation of different iodine concentration rods inserted in head- and body-sized phantoms using different imaging protocols. These protocols are designed to have the same dose level (CTDIvol) but using different X-ray tube voltage settings (kVp). Methods: Different concentrations of iodine objects inserted in a head size phantom and a body size phantom are imaged on a 64-slice commercial CT scanner. Scanning protocols with various tube voltages (80, 100, and 120 kVp) and current settingsmore » are selected, which output the same absorbed dose level (CTDIvol). Because the phantom design (size of the iodine objects, the air gap between the inserted objects and the phantom) is not ideal for a model observer study, the acquired CT images are used to generate simulation images with four different sizes and five different contracts iodine objects. For each type of the objects, 500 images (100 x 100 pixels) are generated for the observer study. The observer selected in this study is the channelized scanning linear observer which could be applied to estimate the size and the contrast. The figure of merit used is the correct estimation ratio. The mean and the variance are estimated by the shuffle method. Results: The results indicate that the protocols with 100 kVp tube voltage setting provides the best performance for iodine insert size and contrast estimation for both head and body phantom cases. Conclusion: This work presents a practical and robust quantitative approach using channelized scanning linear observer to study contrast and size estimation performance from different CT protocols. Different protocols at same CTDIvol setting could Result in different image quality performance. The relationship between the absorbed dose and the diagnostic image quality is not linear.« less
Hwang, Inpyeong; Cho, Jeong Yeon; Kim, Sang Youn; Oh, Seung-June; Ku, Ja Hyeon; Lee, Joongyup; Kim, Seung Hyup
2015-12-01
The aim of the present study was to investigate the feasibility and image quality of excretory CT urography performed using low iodine-concentration contrast media and low tube voltage. This prospective study enrolled 63 patients who undergoing CT urography. The subjects were randomized into two groups of an excretory phase CT urography protocol and received either 240 mg I/mL of contrast media and 80 kVp of tube voltage (low-concentration protocol, n=32) or 350 mg I/mL and 120 kVp (conventional protocol, n=31). Two readers qualitatively evaluated images for sharpness of the urinary tract, image noise, streak artifact and overall diagnostic acceptability. The mean attenuation, signal-to-noise ratio, contrast-to-noise ratio and figure of merit were measured in the urinary tract. The non-inferiority test assessed the diagnostic acceptability between the two protocol groups. The low-concentration protocol showed a significantly lower effective radiation dose (3.44 vs. 5.70 mSv, P<.001). The diagnostic acceptability was significantly lower in the low-concentration protocol with iterative reconstruction algorithm than in the conventional protocol (4.06±0.45 vs. 4.50±0.37, P<.001), however, all subjects showed at least more than standard diagnostic acceptability and the difference resided in the predefined non-inferiority margin. The signal-to-noise ratio, contrast-to-noise ratio and figure of merit were significantly higher in the low-concentration protocol along the entire urinary tract (P<.001). CT urography using 240 mg I/mL iodine contrast media, 80 kVp tube voltage and an iterative reconstruction algorithm is beneficial to reduce radiation dose and iodine load, and its objective image quality and subjective diagnostic acceptability is not inferior to that of conventional CT urography. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sahbaee, Pooyan, E-mail: psahbae@ncsu.edu; Segars, W. Paul; Samei, Ehsan
2014-07-15
Purpose: This study aimed to provide a comprehensive patient-specific organ dose estimation across a multiplicity of computed tomography (CT) examination protocols. Methods: A validated Monte Carlo program was employed to model a common CT system (LightSpeed VCT, GE Healthcare). The organ and effective doses were estimated from 13 commonly used body and neurological CT examination. The dose estimation was performed on 58 adult computational extended cardiac-torso phantoms (35 male, 23 female, mean age 51.5 years, mean weight 80.2 kg). The organ dose normalized by CTDI{sub vol} (h factor) and effective dose normalized by the dose length product (DLP) (k factor)more » were calculated from the results. A mathematical model was derived for the correlation between the h and k factors with the patient size across the protocols. Based on this mathematical model, a dose estimation iPhone operating system application was designed and developed to be used as a tool to estimate dose to the patients for a variety of routinely used CT examinations. Results: The organ dose results across all the protocols showed an exponential decrease with patient body size. The correlation was generally strong for the organs which were fully or partially located inside the scan coverage (Pearson sample correlation coefficient (r) of 0.49). The correlation was weaker for organs outside the scan coverage for which distance between the organ and the irradiation area was a stronger predictor of dose to the organ. For body protocols, the effective dose before and after normalization by DLP decreased exponentially with increasing patient's body diameter (r > 0.85). The exponential relationship between effective dose and patient's body diameter was significantly weaker for neurological protocols (r < 0.41), where the trunk length was a slightly stronger predictor of effective dose (0.15 < r < 0.46). Conclusions: While the most accurate estimation of a patient dose requires specific modeling of the patient anatomy, a first order approximation of organ and effective doses from routine CT scan protocols can be reasonably estimated using size specific factors. Estimation accuracy is generally poor for organ outside the scan range and for neurological protocols. The dose calculator designed in this study can be used to conveniently estimate and report the dose values for a patient across a multiplicity of CT scan protocols.« less
Lee, Eunsol; Goo, Hyun Woo; Lee, Jae-Yeong
2015-08-01
It is necessary to develop a mechanism to estimate and analyze cumulative radiation risks from multiple CT exams in various clinical scenarios in children. To identify major contributors to high cumulative CT dose estimates using actual dose-length product values collected for 5 years in children. Between August 2006 and July 2011 we reviewed 26,937 CT exams in 13,803 children. Among them, we included 931 children (median age 3.5 years, age range 0 days-15 years; M:F = 533:398) who had 5,339 CT exams. Each child underwent at least three CT scans and had accessible radiation dose reports. Dose-length product values were automatically extracted from DICOM files and we used recently updated conversion factors for age, gender, anatomical region and tube voltage to estimate CT radiation dose. We tracked the calculated CT dose estimates to obtain a 5-year cumulative value for each child. The study population was divided into three groups according to the cumulative CT dose estimates: high, ≥30 mSv; moderate, 10-30 mSv; and low, <10 mSv. We reviewed clinical data and CT protocols to identify major contributors to high and moderate cumulative CT dose estimates. Median cumulative CT dose estimate was 5.4 mSv (range 0.5-71.1 mSv), and median number of CT scans was 4 (range 3-36). High cumulative CT dose estimates were most common in children with malignant tumors (57.9%, 11/19). High frequency of CT scans was attributed to high cumulative CT dose estimates in children with ventriculoperitoneal shunt (35 in 1 child) and malignant tumors (range 18-49). Moreover, high-dose CT protocols, such as multiphase abdomen CT (median 4.7 mSv) contributed to high cumulative CT dose estimates even in children with a low number of CT scans. Disease group, number of CT scans, and high-dose CT protocols are major contributors to higher cumulative CT dose estimates in children.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hoven, Andor F. van den, E-mail: a.f.vandenhoven@umcutrecht.nl; Prince, Jip F.; Keizer, Bart de
PurposeTo optimize a C-arm computed tomography (CT) protocol for radioembolization (RE), specifically for extrahepatic shunting and parenchymal enhancement.Materials and MethodsA prospective development study was performed per IDEAL recommendations. A literature-based protocol was applied in patients with unresectable and chemorefractory liver malignancies undergoing an angiography before radioembolization. Contrast and scan settings were adjusted stepwise and repeatedly reviewed in a consensus meeting. Afterwards, two independent raters analyzed all scans. A third rater evaluated the SPECT/CT scans as a reference standard for extrahepatic shunting and lack of target segment perfusion.ResultsFifty scans were obtained in 29 procedures. The first protocol, using a 6 s delaymore » and 10 s scan, showed insufficient parenchymal enhancement. In the second protocol, the delay was determined by timing parenchymal enhancement on DSA power injection (median 8 s, range 4–10 s): enhancement improved, but breathing artifacts increased (from 0 to 27 %). Since the third protocol with a 5 s scan decremented subjective image quality, the second protocol was deemed optimal. Median CNR (range) was 1.7 (0.6–3.2), 2.2 (−1.4–4.0), and 2.1 (−0.3–3.0) for protocol 1, 2, and 3 (p = 0.80). Delineation of perfused segments was possible in 57, 73, and 44 % of scans (p = 0.13). In all C-arm CTs combined, the negative predictive value was 95 % for extrahepatic shunting and 83 % for lack of target segment perfusion.ConclusionAn optimized C-arm CT protocol was developed that can be used to detect extrahepatic shunts and non-perfusion of target segments during RE.« less
CT scans for pulmonary surveillance may be overused in lower-grade sarcoma.
Miller, Benjamin J; Carmody Soni, Emily E; Reith, John D; Gibbs, C Parker; Scarborough, Mark T
2012-01-01
Chest CT scans are often used to monitor patients after excision of a sarcoma. Although sensitive, CT scans are more expensive than chest radiographs and are associated with possible health risks from a higher radiation dose. We hypothesized that a program based upon limited CT scans in lower-grade sarcoma could be efficacious and less expensive. We retrospectively assigned patients to a high-risk or low-risk hypothetical protocol. Eighty-three low- or intermediate-grade soft tissue sarcomas met our inclusion criteria. Eight patients had pulmonary metastasis. A protocol based on selective CT scans for high-risk patients would have identified seven out of eight lesions. The incremental cost-effectiveness ratio for routine CT scans was $731,400. A program based upon selective CT scans for higher-risk patients is accurate, spares unnecessary radiation to many patients, and is less expensive.
SU-F-P-04: Implementation of Dose Monitoring Software: Successes and Pitfalls
DOE Office of Scientific and Technical Information (OSTI.GOV)
Och, J
2016-06-15
Purpose: to successfully install a dose monitoring software (DMS) application to assist in CT protocol and dose management. Methods: Upon selecting the DMS, we began our implementation of the application. A working group composed of Medical Physics, Radiology Administration, Information Technology, and CT technologists was formed. On-site training in the application was supplied by the vendor. The decision was made to apply the process for all the CT protocols on all platforms at all facilities. Protocols were painstakingly mapped to the correct masters, and the system went ‘live’. Results: We are routinely using DMS as a tool in our Clinicalmore » Performance CT QA program. It is useful in determining the effectiveness of revisions to existing protocols, and establishing performance baselines for new units. However, the implementation was not without difficulty. We identified several pitfalls and obstacles which frustrated progress. Including: Training deficiencies, Nomenclature problems, Communication, DICOM variability. Conclusion: Dose monitoring software can be a potent tool for QA. However, implementation of the program can be problematic and requires planning, organization and commitment.« less
Performance evaluation of the CT component of the IRIS PET/CT preclinical tomograph
NASA Astrophysics Data System (ADS)
Panetta, Daniele; Belcari, Nicola; Tripodi, Maria; Burchielli, Silvia; Salvadori, Piero A.; Del Guerra, Alberto
2016-01-01
In this paper, we evaluate the physical performance of the CT component of the IRIS scanner, a novel combined PET/CT scanner for preclinical imaging. The performance assessment is based on phantom measurement for the determination of image quality parameters (spatial resolution, linearity, geometric accuracy, contrast to noise ratio) and reproducibility in dynamic (4D) imaging. The CTDI100 has been measured free in air with a pencil ionization chamber, and the animal dose was calculated using Monte Carlo derived conversion factors taken from the literature. The spatial resolution at the highest quality protocol was 6.9 lp/mm at 10% of the MTF, using the smallest reconstruction voxel size of 58.8 μm. The accuracy of the reconstruction voxel size was within 0.1%. The linearity of the CT numbers as a function of the concentration of iodine was very good, with R2>0.996 for all the tube voltages. The animal dose depended strongly on the scanning protocol, ranging from 158 mGy for the highest quality protocol (2 min, 80 kV) to about 12 mGy for the fastest protocol (7.3 s, 80 kV). In 4D dynamic modality, the maximum scanning rate reached was 3.1 frames per minute, using a short-scan protocol with 7.3 s of scan time per frame at the isotropic voxel size of 235 μm. The reproducibility of the system was high throughout the 10 frames acquired in dynamic modality, with a standard deviation of the CT values of all frames <8 HU and an average spatial reproducibility within 30% of the voxel size across all the field of view. Example images obtained during animal experiments are also shown.
Cros, Maria; Geleijns, Jacob; Joemai, Raoul M S; Salvadó, Marçal
2016-01-01
The purpose of this study was to estimate the patient dose from perfusion CT examinations of the brain, lung tumors, and the liver on a cone-beam 320-MDCT scanner using a Monte Carlo simulation and the recommendations of the International Commission on Radiological Protection (ICRP). A Monte Carlo simulation based on the Electron Gamma Shower Version 4 package code was used to calculate organ doses and the effective dose in the reference computational phantoms for an adult man and adult woman as published by the ICRP. Three perfusion CT acquisition protocols--brain, lung tumor, and liver perfusion--were evaluated. Additionally, dose assessments were performed for the skin and for the eye lens. Conversion factors were obtained to estimate effective doses and organ doses from the volume CT dose index and dose-length product. The sex-averaged effective doses were approximately 4 mSv for perfusion CT of the brain and were between 23 and 26 mSv for the perfusion CT body protocols. The eye lens dose from the brain perfusion CT examination was approximately 153 mGy. The sex-averaged peak entrance skin dose (ESD) was 255 mGy for the brain perfusion CT studies, 157 mGy for the lung tumor perfusion CT studies, and 172 mGy for the liver perfusion CT studies. The perfusion CT protocols for imaging the brain, lung tumors, and the liver performed on a 320-MDCT scanner yielded patient doses that are safely below the threshold doses for deterministic effects. The eye lens dose, peak ESD, and effective doses can be estimated for other clinical perfusion CT examinations from the conversion factors that were derived in this study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mench, A; Lipnharski, I; Carranza, C
Purpose: New radiation dose reduction technologies are emerging constantly in the medical imaging field. The latest of these technologies, iterative reconstruction (IR) in CT, presents the ability to reduce dose significantly and hence provides great opportunity for CT protocol optimization. However, without effective analysis of image quality, the reduction in radiation exposure becomes irrelevant. This work explores the use of postmortem subjects as an image quality assessment medium for protocol optimizations in abdominal CT. Methods: Three female postmortem subjects were scanned using the Abdomen-Pelvis (AP) protocol at reduced minimum tube current and target noise index (SD) settings of 12.5, 17.5,more » 20.0, and 25.0. Images were reconstructed using two strengths of iterative reconstruction. Radiologists and radiology residents from several subspecialties were asked to evaluate 8 AP image sets including the current facility default scan protocol and 7 scans with the parameters varied as listed above. Images were viewed in the soft tissue window and scored on a 3-point scale as acceptable, borderline acceptable, and unacceptable for diagnosis. The facility default AP scan was identified to the reviewer while the 7 remaining AP scans were randomized and de-identified of acquisition and reconstruction details. The observers were also asked to comment on the subjective image quality criteria they used for scoring images. This included visibility of specific anatomical structures and tissue textures. Results: Radiologists scored images as acceptable or borderline acceptable for target noise index settings of up to 20. Due to the postmortem subjects’ close representation of living human anatomy, readers were able to evaluate images as they would those of actual patients. Conclusion: Postmortem subjects have already been proven useful for direct CT organ dose measurements. This work illustrates the validity of their use for the crucial evaluation of image quality during CT protocol optimization, especially when investigating the effects of new technologies.« less
2014-01-01
Background Size and shape of the treatment zone after Irreversible electroporation (IRE) can be difficult to depict due to the use of multiple applicators with complex spatial configuration. Exact geometrical definition of the treatment zone, however, is mandatory for acute treatment control since incomplete tumor coverage results in limited oncological outcome. In this study, the “Chebyshev Center Concept” was introduced for CT 3d rendering to assess size and position of the maximum treatable tumor at a specific safety margin. Methods In seven pig livers, three different IRE protocols were applied to create treatment zones of different size and shape: Protocol 1 (n = 5 IREs), Protocol 2 (n = 5 IREs), and Protocol 3 (n = 5 IREs). Contrast-enhanced CT was used to assess the treatment zones. Technique A consisted of a semi-automated software prototype for CT 3d rendering with the “Chebyshev Center Concept” implemented (the “Chebyshev Center” is the center of the largest inscribed sphere within the treatment zone) with automated definition of parameters for size, shape and position. Technique B consisted of standard CT 3d analysis with manual definition of the same parameters but position. Results For Protocol 1 and 2, short diameter of the treatment zone and diameter of the largest inscribed sphere within the treatment zone were not significantly different between Technique A and B. For Protocol 3, short diameter of the treatment zone and diameter of the largest inscribed sphere within the treatment zone were significantly smaller for Technique A compared with Technique B (41.1 ± 13.1 mm versus 53.8 ± 1.1 mm and 39.0 ± 8.4 mm versus 53.8 ± 1.1 mm; p < 0.05 and p < 0.01). For Protocol 1, 2 and 3, sphericity of the treatment zone was significantly larger for Technique A compared with B. Conclusions Regarding size and shape of the treatment zone after IRE, CT 3d rendering with the “Chebyshev Center Concept” implemented provides significantly different results compared with standard CT 3d analysis. Since the latter overestimates the size of the treatment zone, the “Chebyshev Center Concept” could be used for a more objective acute treatment control. PMID:24410997
A fully automated non-external marker 4D-CT sorting algorithm using a serial cine scanning protocol.
Carnes, Greg; Gaede, Stewart; Yu, Edward; Van Dyk, Jake; Battista, Jerry; Lee, Ting-Yim
2009-04-07
Current 4D-CT methods require external marker data to retrospectively sort image data and generate CT volumes. In this work we develop an automated 4D-CT sorting algorithm that performs without the aid of data collected from an external respiratory surrogate. The sorting algorithm requires an overlapping cine scan protocol. The overlapping protocol provides a spatial link between couch positions. Beginning with a starting scan position, images from the adjacent scan position (which spatial match the starting scan position) are selected by maximizing the normalized cross correlation (NCC) of the images at the overlapping slice position. The process was continued by 'daisy chaining' all couch positions using the selected images until an entire 3D volume was produced. The algorithm produced 16 phase volumes to complete a 4D-CT dataset. Additional 4D-CT datasets were also produced using external marker amplitude and phase angle sorting methods. The image quality of the volumes produced by the different methods was quantified by calculating the mean difference of the sorted overlapping slices from adjacent couch positions. The NCC sorted images showed a significant decrease in the mean difference (p < 0.01) for the five patients.
Sterling, Sarah A.; Miller, W. Ryan; Pryor, Jason; Puskarich, Michael A.; Jones, Alan E.
2015-01-01
Objectives We sought to systematically review and meta-analyze the available data on the association between timing of antibiotic administration and mortality in severe sepsis and septic shock. Data Sources and Study Selection A comprehensive search was performed using a pre-defined protocol. Inclusion criteria: adult patients with severe sepsis or septic shock, reported time to antibiotic administration in relation to ED triage and/or shock recognition, and mortality. Exclusion criteria: immunosuppressed populations, review article, editorial, or non-human studies. Data Extraction Two reviewers screened abstracts with a third reviewer arbitrating. The effect of time to antibiotic administration on mortality was based on current guideline recommendations: 1) administration within 3 hours of ED triage; 2) administration within 1 hour of severe sepsis/septic shock recognition. Odds Ratios (OR) were calculated using a random effect model. The primary outcome was mortality. Data Synthesis 1123 publications were identified and 11 were included in the analysis. Among the 11 included studies, 16,178 patients were evaluable for antibiotic administration from ED triage. Patients who received antibiotics more than 3 hours after ED triage (< 3 hours reference), had a pooled OR for mortality of 1.16 (0.92 to 1.46, p = 0.21). A total of 11,017 patients were evaluable for antibiotic administration from severe sepsis/septic shock recognition. Patients who received antibiotics more than 1 hour after severe sepsis/shock recognition (< 1 hour reference) had a pooled OR for mortality of 1.46 (0.89 to 2.40, p = 0.13). There was no increased mortality in the pooled ORs for each hourly delay from <1 to >5 hours in antibiotic administration from severe sepsis/shock recognition. Conclusion Using the available pooled data we found no significant mortality benefit of administering antibiotics within 3 hours of ED triage or within 1 hour of shock recognition in severe sepsis and septic shock. These results suggest that currently recommended timing metrics as measures of quality of care are not supported by the available evidence. PMID:26121073
ReSTART: A Novel Framework for Resource-Based Triage in Mass-Casualty Events.
Mills, Alex F; Argon, Nilay T; Ziya, Serhan; Hiestand, Brian; Winslow, James
2014-01-01
Current guidelines for mass-casualty triage do not explicitly use information about resource availability. Even though this limitation has been widely recognized, how it should be addressed remains largely unexplored. The authors present a novel framework developed using operations research methods to account for resource limitations when determining priorities for transportation of critically injured patients. To illustrate how this framework can be used, they also develop two specific example methods, named ReSTART and Simple-ReSTART, both of which extend the widely adopted triage protocol Simple Triage and Rapid Treatment (START) by using a simple calculation to determine priorities based on the relative scarcity of transportation resources. The framework is supported by three techniques from operations research: mathematical analysis, optimization, and discrete-event simulation. The authors? algorithms were developed using mathematical analysis and optimization and then extensively tested using 9,000 discrete-event simulations on three distributions of patient severity (representing low, random, and high acuity). For each incident, the expected number of survivors was calculated under START, ReSTART, and Simple-ReSTART. A web-based decision support tool was constructed to help providers make prioritization decisions in the aftermath of mass-casualty incidents based on ReSTART. In simulations, ReSTART resulted in significantly lower mortality than START regardless of which severity distribution was used (paired t test, p<.01). Mean decrease in critical mortality, the percentage of immediate and delayed patients who die, was 8.5% for low-acuity distribution (range ?2.2% to 21.1%), 9.3% for random distribution (range ?0.2% to 21.2%), and 9.1% for high-acuity distribution (range ?0.7% to 21.1%). Although the critical mortality improvement due to ReSTART was different for each of the three severity distributions, the variation was less than 1 percentage point, indicating that the ReSTART policy is relatively robust to different severity distributions. Taking resource limitations into account in mass-casualty situations, triage has the potential to increase the expected number of survivors. Further validation is required before field implementation; however, the framework proposed in here can serve as the foundation for future work in this area. 2014.
Prehospital care in Hong Kong.
Lo, C B; Lai, K K; Mak, K P
2000-09-01
A quick and efficient prehospital emergency response depends on immediate ambulance dispatch, patient assessment, triage, and transport to hospital. During 1999, the Ambulance Command of the Hong Kong Fire Services Department responded to 484,923 calls, which corresponds to 1329 calls each day. Cooperation between the Fire Services Department and the Hospital Authority exists at the levels of professional training of emergency medical personnel, quality assurance, and a coordinated disaster response. In response to the incident at the Hong Kong International Airport in the summer of 1999, when an aircraft overturned during landing, the pre-set quota system was implemented to send patients to designated accident and emergency departments. Furthermore, the 'first crew at the scene' model has been adopted, whereby the command is established and triage process started by the first ambulance crew members to reach the scene. The development of emergency protocols should be accompanied by good field-to-hospital and interhospital communication, the upgrading of decision-making skills, a good monitoring and auditing structure, and commitment to training and skills maintenance.
Bazot, Marc; Daraï, Emile
2017-12-01
The aim of the present review was to evaluate the contribution of clinical examination and imaging techniques, mainly transvaginal sonography and magnetic resonance imaging (MRI) to diagnose deep infiltrating (DE) locations using prisma statement recommendations. Clinical examination has a relative low sensitivity and specificity to diagnose DE. Independently of DE locations, for all transvaginal sonography techniques a pooled sensitivity and specificity of 79% and 94% are observed approaching criteria for a triage test. Whatever the protocol and MRI devices, the pooled sensitivity and specificity for pelvic endometriosis diagnosis were 94% and 77%, respectively. For rectosigmoid endometriosis, pooled sensitivity and specificity of MRI were 92% and 96%, respectively fulfilling criteria of replacement test. In conclusion, advances in imaging techniques offer high sensitivity and specificity to diagnose DE with at least triage value and for rectosigmoid endometriosis replacement value imposing a revision of the concept of laparoscopy as the gold standard. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Nakahara, Takehiro; Jinzaki, Masahiro; Niwamae, Nogiku; Saito, Yuuichirou; Arai, Masashi; Tsushima, Yoshito; Kuribayashi, Sachio; Kurabayashi, Masahiko
2014-01-01
Despite the improvement of cardiac CT, right heart visualization remains challenging. We herein describe a new method, called the time-adjusted gradual replacement injection protocol. The aim of this study was to compare this protocol with the split-bolus injection protocol. Fifty-two patients who had undergone dual-source cardiac CT were retrospectively recruited. Twenty-six patients were injected by using the split-bolus injection protocol, and 26 patients were injected by using the time-adjusted gradual replacement injection protocol. For this method, we injected contrast medium for 10 seconds at a flow rate of 0.07 × body weight mL/s, then gradually replaced the contrast material with saline until 2 seconds before finishing the scans. The CT attenuation was measured in 4 chambers, the aorta, and the coronary arteries. The visualization of the anatomic structures and the occurrence and severity of streak artifacts were scored for the cardiac structures in the heart. For the analyses, either Welch t-test or Student t-test was performed. In the right heart, the CT values and visualization scores were significantly higher in the time-adjusted replacement injection group than in the split-bolus injection group, whereas the artifact scores were comparable between the 2 groups. The CT values, visualization scores, and artifact scores of the left heart were not significantly different between the 2 groups. In this study, the time-adjusted gradual replacement injection protocol provided excellent attenuation for visualization of the right heart. This method may help to accurately evaluate the right cardiac anatomy and thereby identify any potential diseases. Copyright © 2014 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.
Frood, R; Baren, J; McDermott, G; Bottomley, D; Patel, C; Scarsbrook, A
2018-04-30
To evaluate the efficacy of single time-point half-body (skull base to thighs) fluorine-18 choline positron emission tomography-computed tomography (PET-CT) compared to a triple-phase acquisition protocol in the detection of prostate carcinoma recurrence. Consecutive choline PET-CT studies performed at a single tertiary referral centre in patients with biochemical recurrence of prostate carcinoma between September 2012 and March 2017 were reviewed retrospectively. The indication for the study, imaging protocol used, imaging findings, whether management was influenced by the PET-CT, and subsequent patient outcome were recorded. Ninety-one examinations were performed during the study period; 42 were carried out using a triple-phase protocol (dynamic pelvic imaging for 20 minutes after tracer injection, half-body acquisition at 60 minutes and delayed pelvic scan at 90 minutes) between 2012 and August 2015. Subsequently following interim review of diagnostic performance, a streamlined protocol and appropriate-use criteria were introduced. Forty-nine examinations were carried out using the single-phase protocol between 2015 and 2017. Twenty-nine (69%) of the triple-phase studies were positive for recurrence compared to 38 (78%) of the single-phase studies. Only one patient who had a single-phase study would have benefited from a dynamic acquisition, they have required no further treatment or imaging and are currently under prostate-specific antigen (PSA) surveillance. Choline PET-CT remains a useful tool for the detection of prostate recurrence when used in combination with appropriate-use criteria. Removal of dynamic and delayed acquisition phases reduces study time without adversely affecting accuracy. Benefits include shorter imaging time which improves patient comfort, reduced cost, and improved scanner efficiency. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Dillman, Jonathan R.; Goodsitt, Mitchell M.; Christodoulou, Emmanuel G.; Keshavarzi, Nahid; Strouse, Peter J.
2014-01-01
Purpose To retrospectively compare image quality and radiation dose between a reduced-dose computed tomographic (CT) protocol that uses model-based iterative reconstruction (MBIR) and a standard-dose CT protocol that uses 30% adaptive statistical iterative reconstruction (ASIR) with filtered back projection. Materials and Methods Institutional review board approval was obtained. Clinical CT images of the chest, abdomen, and pelvis obtained with a reduced-dose protocol were identified. Images were reconstructed with two algorithms: MBIR and 100% ASIR. All subjects had undergone standard-dose CT within the prior year, and the images were reconstructed with 30% ASIR. Reduced- and standard-dose images were evaluated objectively and subjectively. Reduced-dose images were evaluated for lesion detectability. Spatial resolution was assessed in a phantom. Radiation dose was estimated by using volumetric CT dose index (CTDIvol) and calculated size-specific dose estimates (SSDE). A combination of descriptive statistics, analysis of variance, and t tests was used for statistical analysis. Results In the 25 patients who underwent the reduced-dose protocol, mean decrease in CTDIvol was 46% (range, 19%–65%) and mean decrease in SSDE was 44% (range, 19%–64%). Reduced-dose MBIR images had less noise (P > .004). Spatial resolution was superior for reduced-dose MBIR images. Reduced-dose MBIR images were equivalent to standard-dose images for lungs and soft tissues (P > .05) but were inferior for bones (P = .004). Reduced-dose 100% ASIR images were inferior for soft tissues (P < .002), lungs (P < .001), and bones (P < .001). By using the same reduced-dose acquisition, lesion detectability was better (38% [32 of 84 rated lesions]) or the same (62% [52 of 84 rated lesions]) with MBIR as compared with 100% ASIR. Conclusion CT performed with a reduced-dose protocol and MBIR is feasible in the pediatric population, and it maintains diagnostic quality. © RSNA, 2013 Online supplemental material is available for this article. PMID:24091359
Widmann, G; Juranek, D; Waldenberger, F; Schullian, P; Dennhardt, A; Hoermann, R; Steurer, M; Gassner, E-M; Puelacher, W
2017-08-01
Dose reduction on CT scans for surgical planning and postoperative evaluation of midface and orbital fractures is an important concern. The purpose of this study was to evaluate the variability of various low-dose and iterative reconstruction techniques on the visualization of orbital soft tissues. Contrast-to-noise ratios of the optic nerve and inferior rectus muscle and subjective scores of a human cadaver were calculated from CT with a reference dose protocol (CT dose index volume = 36.69 mGy) and a subsequent series of low-dose protocols (LDPs I-4: CT dose index volume = 4.18, 2.64, 0.99, and 0.53 mGy) with filtered back-projection (FBP) and adaptive statistical iterative reconstruction (ASIR)-50, ASIR-100, and model-based iterative reconstruction. The Dunn Multiple Comparison Test was used to compare each combination of protocols (α = .05). Compared with the reference dose protocol with FBP, the following statistically significant differences in contrast-to-noise ratios were shown (all, P ≤ .012) for the following: 1) optic nerve: LDP-I with FBP; LDP-II with FBP and ASIR-50; LDP-III with FBP, ASIR-50, and ASIR-100; and LDP-IV with FBP, ASIR-50, and ASIR-100; and 2) inferior rectus muscle: LDP-II with FBP, LDP-III with FBP and ASIR-50, and LDP-IV with FBP, ASIR-50, and ASIR-100. Model-based iterative reconstruction showed the best contrast-to-noise ratio in all images and provided similar subjective scores for LDP-II. ASIR-50 had no remarkable effect, and ASIR-100, a small effect on subjective scores. Compared with a reference dose protocol with FBP, model-based iterative reconstruction may show similar diagnostic visibility of orbital soft tissues at a CT dose index volume of 2.64 mGy. Low-dose technology and iterative reconstruction technology may redefine current reference dose levels in maxillofacial CT. © 2017 by American Journal of Neuroradiology.
Thai, Wai-ee; Wai, Bryan; Lin, Kaity; Cheng, Teresa; Heist, E. Kevin; Hoffmann, Udo; Singh, Jagmeet; Truong, Quynh A.
2012-01-01
Background Efforts to reduce radiation from cardiac computed tomography (CT) are essential. Using a prospectively triggered, high-pitch dual source CT (DSCT) protocol, we aim to determine the radiation dose and image quality (IQ) in patients undergoing pulmonary vein (PV) imaging. Methods and Results In 94 patients (61±9 years, 71% male) who underwent 128-slice DSCT (pitch 3.4), radiation dose and IQ were assessed and compared between 69 patients in sinus rhythm (SR) and 25 in atrial fibrillation (AF). Radiation dose was compared in a subset of 19 patients with prior retrospective or prospectively triggered CT PV scans without high-pitch. In a subset of 18 patients with prior magnetic resonance imaging (MRI) for PV assessment, PV anatomy and scan duration were compared to high-pitch CT. Using the high-pitch protocol, total effective radiation dose was 1.4 [1.3, 1.9] mSv, with no difference between SR and AF (1.4 vs 1.5 mSv, p=0.22). No high-pitch CT scans were non-diagnostic or had poor IQ. Radiation dose was reduced with high-pitch (1.6 mSv) compared to standard protocols (19.3 mSv, p<0.0001). This radiation dose reduction was seen with SR (1.5 vs 16.7 mSv, p<0.0001) but was more profound with AF (1.9 vs 27.7 mSv, p=0.039). There was excellent agreement of PV anatomy (kappa 0.84, p<0.0001), and a shorter CT scan duration (6 minutes) compared to MRI (41 minutes, p<0.0001). Conclusions Using a high-pitch DSCT protocol, PV imaging can be performed with minimal radiation dose, short scan acquisition, and excellent IQ in patients with SR or AF. This protocol highlights the success of new cardiac CT technology to minimize radiation exposure, giving clinicians a new low-dose imaging alternative to assess PV anatomy. PMID:22586259
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smitherman, C; Chen, B; Samei, E
2014-06-15
Purpose: This work involved a comprehensive modeling of task-based performance of CT across a wide range of protocols. The approach was used for optimization and consistency of dose and image quality within a large multi-vendor clinical facility. Methods: 150 adult protocols from the Duke University Medical Center were grouped into sub-protocols with similar acquisition characteristics. A size based image quality phantom (Duke Mercury Phantom) was imaged using these sub-protocols for a range of clinically relevant doses on two CT manufacturer platforms (Siemens, GE). The images were analyzed to extract task-based image quality metrics such as the Task Transfer Function (TTF),more » Noise Power Spectrum, and Az based on designer nodule task functions. The data were analyzed in terms of the detectability of a lesion size/contrast as a function of dose, patient size, and protocol. A graphical user interface (GUI) was developed to predict image quality and dose to achieve a minimum level of detectability. Results: Image quality trends with variations in dose, patient size, and lesion contrast/size were evaluated and calculated data behaved as predicted. The GUI proved effective to predict the Az values representing radiologist confidence for a targeted lesion, patient size, and dose. As an example, an abdomen pelvis exam for the GE scanner, with a task size/contrast of 5-mm/50-HU, and an Az of 0.9 requires a dose of 4.0, 8.9, and 16.9 mGy for patient diameters of 25, 30, and 35 cm, respectively. For a constant patient diameter of 30 cm, the minimum detected lesion size at those dose levels would be 8.4, 5, and 3.9 mm, respectively. Conclusion: The designed CT protocol optimization platform can be used to evaluate minimum detectability across dose levels and patient diameters. The method can be used to improve individual protocols as well as to improve protocol consistency across CT scanners.« less
2014-01-01
Background The Amberg-Schwandorf Algorithm for Primary Triage (ASAV) is a novel primary triage concept specifically for physician manned emergency medical services (EMS) systems. In this study, we determined the diagnostic reliability and the time requirements of ASAV triage. Methods Seven hundred eighty triage runs performed by 76 trained EMS providers of varying professional qualification were included into the study. Patients were simulated using human dummies with written vital signs sheets. Triage results were compared to a standard solution, which was developed in a modified Delphi procedure. Test performance parameters (e.g. sensitivity, specificity, likelihood ratios (LR), under-triage, and over-triage) were calculated. Time measurements comprised the complete triage and tagging process and included the time span for walking to the subsequent patient. Results were compared to those published for mSTaRT. Additionally, a subgroup analysis was performed for employment status (career/volunteer), team qualification, and previous triage training. Results For red patients, ASAV sensitivity was 87%, specificity 91%, positive LR 9.7, negative LR 0.139, over-triage 6%, and under-triage 10%. There were no significant differences related to mSTaRT. Per patient, ASAV triage required a mean of 35.4 sec (75th percentile 46 sec, 90th percentile 58 sec). Volunteers needed slightly more time to perform triage than EMS professionals. Previous mSTaRT training of the provider reduced under-triage significantly. There were significant differences in time requirements for triage depending on the expected triage category. Conclusions The ASAV is a specific concept for primary triage in physician governed EMS systems. It may detect red patients reliably. The test performance criteria are comparable to that of mSTaRT, whereas ASAV triage might be accomplished slightly faster. From the data, there was no evidence for a clinically significant reliability difference between typical staffing of mobile intensive care units, patient transport ambulances, or disaster response volunteers. Up to now, there is no clinical validation of either triage concept. Therefore, reality based evaluation studies are needed. PMID:25214310
Morton, Ryan P; Reynolds, Renee M; Ramakrishna, Rohan; Levitt, Michael R; Hopper, Richard A; Lee, Amy; Browd, Samuel R
2013-10-01
In this study, the authors describe their experience with a low-dose head CT protocol for a preselected neurosurgical population at a dedicated pediatric hospital (Seattle Children's Hospital), the largest number of patients with this protocol reported to date. All low-dose head CT scans between October 2011 and November 2012 were reviewed. Two different low-dose radiation dosages were used, at one-half or one-quarter the dose of a standard head CT scan, based on patient characteristics agreed upon by the neurosurgery and radiology departments. Patient information was also recorded, including diagnosis and indication for CT scan. Six hundred twenty-four low-dose head CT procedures were performed within the 12-month study period. Although indications for the CT scans varied, the most common reason was to evaluate the ventricles and catheter placement in hydrocephalic patients with shunts (70%), followed by postoperative craniosynostosis imaging (12%). These scans provided adequate diagnostic imaging, and no patient required a follow-up full-dose CT scan as a result of poor image quality on a low-dose CT scan. Overall physician comfort and satisfaction with interpretation of the images was high. An additional 2150 full-dose head CT scans were performed during the same 12-month time period, making the total number of CT scans 2774. This value compares to 3730 full-dose head CT scans obtained during the year prior to the study when low-dose CT and rapid-sequence MRI was not a reliable option at Seattle Children's Hospital. Thus, over a 1-year period, 22% of the total CT scans were able to be converted to low-dose scans, and full-dose CT scans were able to be reduced by 42%. The implementation of a low-dose head CT protocol substantially reduced the amount of ionizing radiation exposure in a preselected population of pediatric neurosurgical patients. Image quality and diagnostic utility were not significantly compromised.
Menditto, Vincenzo G; Lucci, Moira; Polonara, Stefano; Pomponio, Giovanni; Gabrielli, Armando
2012-06-01
Patients receiving warfarin who experience minor head injury are at risk of intracranial hemorrhage, and optimal management after a single head computed tomography (CT) scan is unclear. We evaluate a protocol of 24-hour observation followed by a second head CT scan. In this prospective case series, we enrolled consecutive patients receiving warfarin and showing no intracranial lesions on a first CT scan after minor head injury treated at a Level II trauma center. We implemented a structured clinical pathway, including 24-hour observation and a CT scan performed before discharge. We then evaluated the frequency of death, admission, neurosurgery, and delayed intracranial hemorrhage. We enrolled and observed 97 consecutive patients. Ten refused the second CT scan and were well during 30-day follow-up. Repeated CT scanning in the remaining 87 patients revealed a new hemorrhage lesion in 5 (6%), with 3 subsequently hospitalized and 1 receiving craniotomy. Two patients discharged after completing the study protocol with 2 negative CT scan results were admitted 2 and 8 days later with symptomatic subdural hematomas; neither received surgery. Two of the 5 patients with delayed bleeding at 24 hours had an initial international normalized ratio greater than 3.0, as did both patients with delayed bleeding beyond 24 hours. The relative risk of delayed hemorrhage with an initial international normalized ratio greater than 3.0 was 14 (95% confidence interval 4 to 49). For patients receiving warfarin who experience minor head injury and have a negative initial head CT scan result, a protocol of 24-hour observation followed by a second CT scan will identify most occurrences of delayed bleeding. An initial international normalized ratio greater than 3 suggests higher risk. Copyright © 2011 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.
Faure, Marguerite E; Swart, Laurens E; Dijkshoorn, Marcel L; Bekkers, Jos A; van Straten, Marcel; Nieman, Koen; Parizel, Paul M; Krestin, Gabriel P; Budde, Ricardo P J
2018-05-01
Multidetector CT (MDCT) is a valuable tool for functional prosthetic heart valve (PHV) assessment. However, radiation exposure remains a concern. We assessed a novel CT-acquisition protocol for comprehensive PHV evaluation at limited dose. Patients with a PHV were scanned using a third-generation dual-source CT scanner (DSCT) and iterative reconstruction technique (IR). Three acquisitions were obtained: a non-enhanced scan; a contrast-enhanced, ECG-triggered, arterial CT angiography (CTA) scan with reconstructions at each 5 % of the R-R interval; and a delayed high-pitch CTA of the entire chest. Image quality was scored on a five-point scale. Radiation dose was obtained from the reported CT dose index (CTDI) and dose length product (DLP). We analysed 43 CT examinations. Mean image quality score was 4.1±1.4, 4.7±0.5 and 4.2±0.6 for the non-contrast-enhanced, arterial and delayed acquisitions, respectively, with a total mean image quality of 4.3±0.7. Mean image quality for leaflet motion was 3.9±1.4. Mean DLP was 28.2±17.1, 457.3±168.6 and 68.5±47.2 mGy.cm for the non-contrast-enhanced (n=40), arterial (n=43) and delayed acquisition (n=43), respectively. The mean total DLP was 569±208 mGy.cm and mean total radiation dose was 8.3±3.0 mSv (n=43). Comprehensive assessment of PHVs is possible using DSCT and IR at moderate radiation dose. • Prosthetic heart valve dysfunction is a potentially life-threatening condition. • Dual-source CT can adequately assess valve leaflet motion and anatomy. • We assessed a comprehensive protocol with three acquisitions for PHV evaluation. • This protocol is associated with good image quality and limited dose.
Higashigaito, K; Becker, A S; Sprengel, K; Simmen, H-P; Wanner, G; Alkadhi, H
2016-09-01
To demonstrate the feasibility and accuracy of automatic radiation dose monitoring software for computed tomography (CT) of trauma patients in a clinical setting over time, and to evaluate the potential of radiation dose reduction using iterative reconstruction (IR). In a time period of 18 months, data from 378 consecutive thoraco-abdominal CT examinations of trauma patients were extracted using automatic radiation dose monitoring software, and patients were split into three cohorts: cohort 1, 64-section CT with filtered back projection, 200 mAs tube current-time product; cohort 2, 128-section CT with IR and identical imaging protocol; cohort 3, 128-section CT with IR, 150 mAs tube current-time product. Radiation dose parameters from the software were compared with the individual patient protocols. Image noise was measured and image quality was semi-quantitatively determined. Automatic extraction of radiation dose metrics was feasible and accurate in all (100%) patients. All CT examinations were of diagnostic quality. There were no differences between cohorts 1 and 2 regarding volume CT dose index (CTDIvol; p=0.62), dose-length product (DLP), and effective dose (ED, both p=0.95), while noise was significantly lower (chest and abdomen, both -38%, p<0.017). Compared to cohort 1, CTDIvol, DLP, and ED in cohort 3 were significantly lower (all -25%, p<0.017), similar to the noise in the chest (-32%) and abdomen (-27%, both p<0.017). Compared to cohort 2, CTDIvol (-28%), DLP, and ED (both -26%) in cohort 3 was significantly lower (all, p<0.017), while noise in the chest (+9%) and abdomen (+18%) was significantly higher (all, p<0.017). Automatic radiation dose monitoring software is feasible and accurate, and can be implemented in a clinical setting for evaluating the effects of lowering radiation doses of CT protocols over time. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Thinking strategies used by Registered Nurses during emergency department triage.
Göransson, Katarina E; Ehnfors, Margareta; Fonteyn, Marsha E; Ehrenberg, Anna
2008-01-01
This paper is a report of a study to describe and compare thinking strategies and cognitive processing in the emergency department triage process by Registered Nurses with high and low triage accuracy. Sound clinical reasoning and accurate decision-making are integral parts of modern nursing practice and are of vital importance during triage in emergency departments. Although studies have shown that individual and contextual factors influence the decisions of Registered Nurses in the triage process, others have failed to explain the relationship between triage accuracy and clinical experience. Furthermore, no study has shown the relationship between Registered Nurses' thinking strategies and their triage accuracy. Using the 'think aloud' method, data were collected in 2004-2005 from 16 RNs working in Swedish emergency departments who had previously participated in a study examining triage accuracy. Content analysis of the data was performed. The Registered Nurses used a variety of thinking strategies, ranging from searching for information, generating hypotheses to stating propositions. They structured the triage process in several ways, beginning by gathering data, generating hypotheses or allocating acuity ratings. Comparison of participants' use of thinking strategies and the structure of the triage process based on their previous triage accuracy revealed only slight differences. The wide range of thinking strategies used by Registered Nurses when performing triage indicates that triage decision-making is complex. Further research is needed to ascertain which skills are most important in triage decision-making.
Lell, M M; May, M S; Brand, M; Eller, A; Buder, T; Hofmann, E; Uder, M; Wuest, W
2015-07-01
CT is the imaging technique of choice in the evaluation of midface trauma or inflammatory disease. We performed a systematic evaluation of scan protocols to optimize image quality and radiation exposure on third-generation dual-source CT. CT protocols with different tube voltage (70-150 kV), current (25-300 reference mAs), prefiltration, pitch value, and rotation time were systematically evaluated. All images were reconstructed with iterative reconstruction (Advanced Modeled Iterative Reconstruction, level 2). To individually compare results with otherwise identical factors, we obtained all scans on a frozen human head. Conebeam CT was performed for image quality and dose comparison with multidetector row CT. Delineation of important anatomic structures and incidental pathologic conditions in the cadaver head was evaluated. One hundred kilovolts with tin prefiltration demonstrated the best compromise between dose and image quality. The most dose-effective combination for trauma imaging was Sn100 kV/250 mAs (volume CT dose index, 2.02 mGy), and for preoperative sinus surgery planning, Sn100 kV/150 mAs (volume CT dose index, 1.22 mGy). "Sn" indicates an additional prefiltration of the x-ray beam with a tin filter to constrict the energy spectrum. Exclusion of sinonasal disease was possible with even a lower dose by using Sn100 kV/25 mAs (volume CT dose index, 0.2 mGy). High image quality at very low dose levels can be achieved by using a Sn100-kV protocol with iterative reconstruction. The effective dose is comparable with that of conventional radiography, and the high image quality at even lower radiation exposure favors multidetector row CT over conebeam CT. © 2015 by American Journal of Neuroradiology.
Olerud, Hilde M; Toft, Benthe; Flatabø, Silje; Jahnen, Andreas; Lee, Choonsik; Thierry-Chef, Isabelle
2016-09-01
To assess the range of doses in paediatric CT scans conducted in the 1990s in Norway as input to an international epidemiology study: the EPI-CT study, http://epi-ct.iarc.fr/ . National Cancer Institute dosimetry system for Computed Tomography (NCICT) program based on pre-calculated organ dose conversion coefficients was used to convert CT Dose Index to organ doses in paediatric CT in the 1990s. Protocols reported from local hospitals in a previous Norwegian CT survey were used as input, presuming these were used without optimization for paediatric patients. Large variations in doses between different scanner models and local scan parameter settings are demonstrated. Small children will receive a factor of 2-3 times higher doses compared with adults if the protocols are not optimized for them. For common CT examinations, the doses to the active bone marrow, breast tissue and brain may have exceeded 30 mGy, 60 mGy and 100 mGy respectively, for the youngest children in the 1990s. The doses children received from non-optimised CT examinations during the 1990s are of such magnitude that they may provide statistically significant effects in the EPI-CT study, but probably do not reflect current practice. • Some organ doses from paediatric CT in the 1990s may have exceeded 100 mGy. • Small children may have received doses 2-3 times higher compared with adults. • Different scanner models varied by a factor of 2-3 in dose to patients. • Different local scan parameter settings gave dose variations of a factor 2-3. • Modern CTs and age-adjusted protocols will give much lower paediatric doses.
Kılınçer, Abidin; Akpınar, Erhan; Erbil, Bülent; Ünal, Emre; Karaosmanoğlu, Ali Devrim; Kaynaroğlu, Volkan; Akata, Deniz; Özmen, Mustafa
2017-08-01
To determine the diagnostic accuracy of abdominal CT with compression to the right lower quadrant (RLQ) in adults with acute appendicitis. 168 patients (age range, 18-78 years) were included who underwent contrast-enhanced CT for suspected appendicitis performed either using compression to the RLQ (n = 71) or a standard protocol (n = 97). Outer diameter of the appendix, appendiceal wall thickening, luminal content and associated findings were evaluated in each patient. Kruskal-Wallis, Fisher's and Pearson's chi-squared tests were used for statistical analysis. There was no significant difference in the mean outer diameter (MOD) between compression CT scans (10.6 ± 1.9 mm) and standard protocol (11.2 ± 2.3 mm) in patients with acute appendicitis (P = 1). MOD was significantly lower in the compression group (5.2 ± 0.8 mm) compared to the standard protocol (6.5 ± 1.1 mm) (P < 0.01) in patients without appendicitis. A cut-off value of 6.75 mm for the outer diameter of the appendix was found to be 100% sensitive in the diagnosis of acute appendicitis for both groups. The specificity was higher for compression CT technique (67.7 vs. 94.9%). Normal appendix diameter was significantly smaller in the compression-CT group compared to standard-CT group, increasing diagnostic accuracy of abdominal compression CT. • Normal appendix diameter is significantly smaller in compression CT. • Compression could force contrast material to flow through the appendiceal lumen. • Compression CT may be a CT counterpart of graded compression US.
Brain Imaging Using Mobile CT: Current Status and Future Prospects.
John, Seby; Stock, Sarah; Cerejo, Russell; Uchino, Ken; Winners, Stacey; Russman, Andrew; Masaryk, Thomas; Rasmussen, Peter; Hussain, Muhammad S
2016-01-01
Computed tomography (CT) is an invaluable tool in the diagnosis of many clinical conditions. Several advancements in biomedical engineering have achieved increase in speed, improvements in low-contrast detectability and image quality, and lower radiation. Portable or mobile CT constituted one such important advancement. It is especially useful in evaluating critically ill, intensive care unit patients by scanning them at bedside. A paradigm shift in utilization of mobile CT was its installation in ambulances for the management of acute stroke. Given the time sensitive nature of acute ischemic stroke, Mobile stroke units (MSU) were developed in Germany consisting of an ambulance equipped with a CT scanner, point of care laboratory system, along with teleradiological support. In a radical reconfiguration of stroke care, the MSU would bring the CT scanner to the stroke patient, without waiting for the patient at the emergency room. Two separate MSU projects in Saarland and Berlin demonstrated the safety and feasibility of this concept for prehospital stroke care, showing increased rate of intravenous thrombolysis and significant reduction in time to treatment compared to conventional care. MSU also improved the triage of patients to appropriate and specialized hospitals. Although multiple issues remain yet unanswered with the MSU concept including clinical outcome and cost-effectiveness, the MSU venture is visionary and enables delivery of life-saving and enhancing treatment for ischemic and hemorrhagic stroke. In this review, we discuss the development of mobile CT and its applications, with specific focus on its use in MSUs along with our institution's MSU experience. Copyright © 2015 by the American Society of Neuroimaging.
Kim, Jeong-Yeon; Ryu, Ju Hee; Schellingerhout, Dawid; Sun, In-Cheol; Lee, Su-Kyoung; Jeon, Sangmin; Kim, Jiwon; Kwon, Ick Chan; Nahrendorf, Matthias; Ahn, Cheol-Hee; Kim, Kwangmeyung; Kim, Dong-Eog
2015-01-01
Computed tomography (CT) is the current standard for time-critical decision-making in stroke patients, informing decisions on thrombolytic therapy with tissue plasminogen activator (tPA), which has a narrow therapeutic index. We aimed to develop a CT-based method to directly visualize cerebrovascular thrombi and guide thrombolytic therapy. Glycol-chitosan-coated gold nanoparticles (GC-AuNPs) were synthesized and conjugated to fibrin-targeting peptides, forming fib-GC-AuNP. This targeted imaging agent and non-targeted control agent were characterized in vitro and in vivo in C57Bl/6 mice (n = 107) with FeCl3-induced carotid thrombosis and/or embolic ischemic stroke. Fibrin-binding capacity was superior with fib-GC-AuNPs compared to GC-AuNPs, with thrombi visualized as high density on microCT (mCT). mCT imaging using fib-GC-AuNP allowed the prompt detection and quantification of cerebral thrombi, and monitoring of tPA-mediated thrombolytic effect, which reflected histological stroke outcome. Furthermore, recurrent thrombosis could be diagnosed by mCT without further nanoparticle administration for up to 3 weeks. fib-GC-AuNP-based direct cerebral thrombus imaging greatly enhance the value and information obtainable by regular CT, has multiple uses in basic / translational vascular research, and will likely allow personalized thrombolytic therapy in clinic by a) optimizing tPA-dosing to match thrombus burden, b) enabling the rational triage of patients to more radical therapies such as endovascular clot-retrieval, and c) potentially serving as a theranostic platform for targeted delivery of concurrent thrombolysis. PMID:26199648
Do you see what I see? Insights from using google glass for disaster telemedicine triage.
Cicero, Mark X; Walsh, Barbara; Solad, Yauheni; Whitfill, Travis; Paesano, Geno; Kim, Kristin; Baum, Carl R; Cone, David C
2015-02-01
Disasters are high-stakes, low-frequency events. Telemedicine may offer a useful adjunct for paramedics performing disaster triage. The objective of this study was to determine the feasibility of telemedicine in disaster triage, and to determine whether telemedicine has an effect on the accuracy of triage or the time needed to perform triage. This is a feasibility study in which an intervention team of two paramedics used the mobile device Google Glass (Google Inc; Mountain View, California USA) to communicate with an off-site physician disaster expert. The paramedic team triaged simulated disaster victims at the triennial drill of a commercial airport. The simulated victims had preassigned expected triage levels. The physician had an audio-video interface with the paramedic team and was able to observe the victims remotely. A control team of two paramedics performed disaster triage in the usual fashion. Both teams used the SMART Triage System (TSG Associates LLP; Halifax, England), which assigns patients into Red, Yellow, Green, and Black triage categories. The paramedics were video recorded, and their time required to triage was logged. It was determined whether the intervention team and the control team varied regarding accuracy of triage. Finally, the amount of time the intervention team needed to triage patients when telemedicine was used was compared to when that team did not use telemedicine. The two teams triaged the same 20 patients. There was no significant difference between the two groups in overall triage accuracy (85.7% for the intervention group vs 75.9% for the control group; P = .39). Two patients were triaged with telemedicine. For the intervention group, there was a significant difference in time to triage patients with telemedicine versus those without telemedicine (35.5 seconds; 95% CI, 72.5-143.5 vs 18.5 seconds; 95% CI, 13.4-23.6; P = .041). There was no increase in triage accuracy when paramedics evaluating disaster victims used telemedicine, and telemedicine required more time than conventional triage. There are a number of obstacles to available technology that, if overcome, might improve the utility of telemedicine in disaster response.
Employees' views on home-based, after-hours telephone triage by Dutch GP cooperatives.
Backhaus, Ramona; van Exel, Job; de Bont, Antoinette
2013-11-04
Dutch out-of-hours (OOH) centers find it difficult to attract sufficient triage staff. They regard home-based triage as an option that might attract employees. Specially trained nurses are supposed to conduct triage by telephone from home for after-hours medical care. The central aim of this research is to investigate the views of employees of OOH centers in The Netherlands on home-based telephone triage in after-hours care. The study is a Q methodology study. Triage nurses, general practitioners (GPs) and managers of OOH centers ranked 36 opinion statements on home-based triage. We interviewed 10 participants to help develop and validate the statements for the Q sort, and 77 participants did the Q sort. We identified four views on home-based telephone triage. Two generally favor home-based triage, one highlights some concerns and conditions, and one opposes it out of concern for quality. The four views perceive different sources of credibility for nurse triagists working from home. Home-based telephone triage is a controversial issue among triage nurses, GPs and managers of OOH centers. By identifying consensus and dissension among GPs, triagists, managers and regulators, this study generates four perspectives on home-based triage. In addition, it reveals the conditions considered important for home-based triage.
Employees’ views on home-based, after-hours telephone triage by Dutch GP cooperatives
2013-01-01
Background Dutch out-of-hours (OOH) centers find it difficult to attract sufficient triage staff. They regard home-based triage as an option that might attract employees. Specially trained nurses are supposed to conduct triage by telephone from home for after-hours medical care. The central aim of this research is to investigate the views of employees of OOH centers in The Netherlands on home-based telephone triage in after-hours care. Methods The study is a Q methodology study. Triage nurses, general practitioners (GPs) and managers of OOH centers ranked 36 opinion statements on home-based triage. We interviewed 10 participants to help develop and validate the statements for the Q sort, and 77 participants did the Q sort. Results We identified four views on home-based telephone triage. Two generally favor home-based triage, one highlights some concerns and conditions, and one opposes it out of concern for quality. The four views perceive different sources of credibility for nurse triagists working from home. Conclusion Home-based telephone triage is a controversial issue among triage nurses, GPs and managers of OOH centers. By identifying consensus and dissension among GPs, triagists, managers and regulators, this study generates four perspectives on home-based triage. In addition, it reveals the conditions considered important for home-based triage. PMID:24188407
Burkle, Frederick M
2018-02-01
Triage management remains a major challenge, especially in resource-poor settings such as war, complex humanitarian emergencies, and public health emergencies in developing countries. In triage it is often the disruption of physiology, not anatomy, that is critical, supporting triage methodology based on clinician-assessed physiological parameters as well as anatomy and mechanism of injury. In recent times, too many clinicians from developed countries have deployed to humanitarian emergencies without the physical exam skills needed to assess patients without the benefit of remotely fed electronic monitoring, laboratory, and imaging studies. In triage, inclusion of the once-widely accepted and collectively taught "art of decoding vital signs" with attention to their character and meaning may provide clues to a patient's physiological state, improving triage sensitivity. Attention to decoding vital signs is not a triage methodology of its own or a scoring system, but rather a skill set that supports existing triage methodologies. With unique triage management challenges being raised by an ever-changing variety of humanitarian crises, these once useful skill sets need to be revisited, understood, taught, and utilized by triage planners, triage officers, and teams as a necessary adjunct to physiologically based triage decision-making. (Disaster Med Public Health Preparedness. 2018;12:76-85).
NASA Astrophysics Data System (ADS)
Hashim, S.; Karim, M. K. A.; Bakar, K. A.; Sabarudin, A.; Chin, A. W.; Saripan, M. I.; Bradley, D. A.
2016-09-01
The magnitude of radiation dose in computed tomography (CT) depends on the scan acquisition parameters, investigated herein using an anthropomorphic phantom (RANDO®) and thermoluminescence dosimeters (TLD). Specific interest was in the organ doses resulting from CT thorax examination, the specific k coefficient for effective dose estimation for particular protocols also being determined. For measurement of doses representing five main organs (thyroid, lung, liver, esophagus and skin), TLD-100 (LiF:Mg, Ti) were inserted into selected holes in a phantom slab. Five CT thorax protocols were investigated, one routine (R1) and four that were modified protocols (R2 to R5). Organ doses were ranked from greatest to least, found to lie in the order: thyroid>skin>lung>liver>breast. The greatest dose, for thyroid at 25 mGy, was that in use of R1 while the lowest, at 8.8 mGy, was in breast tissue using R3. Effective dose (E) was estimated using three standard methods: the International Commission on Radiological Protection (ICRP)-103 recommendation (E103), the computational phantom CT-EXPO (E(CTEXPO)) method, and the dose-length product (DLP) based approach. E103 k factors were constant for all protocols, 8% less than that of the universal k factor. Due to inconsistency in tube potential and pitch factor the k factors from CTEXPO were found to vary between 0.015 and 0.010 for protocols R3 and R5. With considerable variation between scan acquisition parameters and organ doses, optimization of practice is necessary in order to reduce patient organ dose.
Pries-Heje, Mia M; Hasselbalch, Rasmus B; Raaschou, Henriette; Rezanavaz-Gheshlagh, Bijan; Heebøll, Hanne; Rehman, Shazia; Kristensen, Mariana; Andersen, Erik Henning; Ravn, Lisbet; Nèmery, Michel C; Lind, Morten N; Boel, Thomas; Ulriksen, Peter Sommer; Iversen, Kasper K
2018-02-17
Several large trials have evaluated the effect of CT screening based on specific symptoms, with varying outcomes. Screening of patients with CT based on their prognosis alone has not been examined before. For moderate-to-high risk patients presenting in the emergency department (ED), the potential gain from a CT scan might outweigh the risk of radiation exposure. We hypothesized that an accelerated "multiple rule out" CT screening of moderate-to-high risk patients will detect many clinically unrecognized diagnoses that affect change in treatment. Patients ≥ 40 years, triaged as high-risk or moderate-to-high risk according to vital signs, were eligible for inclusion. Patients were scanned with a combined ECG-gated and dual energy CT scan of cerebrum, thorax, and abdomen. The impact of the CT scan on patient diagnosis and treatment was examined prospectively by an expert panel. A total of 100 patients were included in the study, (53% female, mean age 73 years [age range, 43-93]). The scan lead to change in treatment or additional examinations in 37 (37%) patients, of which 24 (24%) were diagnostically significant, change in acute treatment in 11 (11%) cases and previously unrecognized malignant tumors in 10 (10%) cases. The mean size specific radiation dose was 15.9 mSv (± 3.1 mSv). Screening with a multi-rule out CT scan of high-risk patients in an ED is feasible and result in discovery of clinically unrecognized diagnoses and malignant tumors, but at the cost of radiation exposure and downstream examinations. The clinical impact of these findings should be evaluated in a larger randomized cohort.
Aissa, Joel; Boos, Johannes; Rubbert, Christian; Caspers, Julian; Schleich, Christoph; Thomas, Christoph; Kröpil, Patric; Antoch, Gerald; Miese, Falk
2017-06-01
The aim of this study was to evaluate the objective and subjective image quality of a novel computed tomography (CT) protocol with reduced radiation dose for body packing with 80 kVp and automated tube current modulation (ATCM) compared to a standard body packing CT protocol. 80 individuals who were examined between March 2012 and July 2015 in suspicion of ingested drug packets were retrospectively included in this study. Thirty-one CT examinations were performed using ATCM and a fixed tube voltage of 80 kVp (group A). Forty-nine CT examinations were performed using a standard protocol with a tube voltage of 120 kVp and a fixed tube current time product of 40 mAs (group B). Subjective and objective image quality and visibility of drug packets were assessed. Radiation exposure of both protocols was compared. Contrast-to-noise ratio (group A: 0.56 ± 0.36; group B: 1.13 ± 0.91) and Signal-to-noise ratio (group A: 3.69 ± 0.98; group B: 7.08 ± 2.67) were significantly lower for group A compared to group B (p < 0.001). Subjectively, image quality was decreased for group A compared to group B (2.5 ± 0.8 vs. 1.2 ± 0.4; p < 0.001). Attenuation of body packets was higher with the new protocol (group A: 362.2 ± 70.3 Hounsfield Units (HU); group B: 210.6 ± 60.2 HU; p = 0.005). Volumetric Computed Tomography Dose Index (CTDIvol) and Dose Length Product (DLP) were significantly lower in group A (CTDIvol 2.2 ± 0.9 mGy, DLP 105.7 ± 52.3 mGycm) as compared to group B (CTDIvol 2.7 ± 0.1 mGy, DLP 126.0 ± 9.7 mGycm, p = 0.002 and p = 0.01). The novel 80 kVp CT protocol with ATCM leads to a significant dose reduction compared to a standard CT body packing protocol. The novel protocol led to a diagnostic image quality and cocaine body packets were reliably detected due to the high attenuation.
[Radiation exposure during spiral-CT of the paranasal sinuses].
Dammann, F; Momino-Traserra, E; Remy, C; Pereira, P L; Baumann, I; Koitschev, A; Claussen, C D
2000-03-01
Determination of the radiation doses in spiral CT of the paranasal sinuses using a variety of mAs values and scan protocols. CT examinations of the paranasal sinuses were performed using an Alderson-Rando phantom. Radiation dose was determined by LiF-TLD at the level of high risk organs in the head and neck region for combinations of different scan parameters (2/3, 3/3, 3/4 mm) and decreasing charges (200, 150, 100, 50, 25 mAs) on a spiral CT. Additional measurements were performed on three other CT scanners using the 2/3 mm protocol at 50 mAs, and a single slice technique (5/5 mm) on one scanner. The lowest dose values found were 1.88 mGy for the eye lenses, 1.35 mGy for the parotid gland, 0.03 mGy for the thyroid gland and 0.1 mGy for the medulla oblongata using 2 mm collimation and 3 mm table feed at 25 mAs. Maximal dose values resulted using the 3/3 mm protocol at 200 mAs (31.00 mGy for the eye lense, 0.65 mGy for the thyroid gland). There were no significant differences found between the different CT scanners. Using up-to-date CT scanners, radiation exposure may be reduced by a factor of 15-20 compared to that of conventional CT technique. Thus, the exposure of the eye lens comes to only a thousandth of the value supposedly inducing a cataract, as published by the ICRP.
Does CT Angiography Matter for Patients with Cervical Spine Injuries?
Hagedorn, John C; Emery, Sanford E; France, John C; Daffner, Scott D
2014-06-04
Cervical injury can be associated with vertebral artery injury. This study was performed to determine the impact of computed tomography (CT) angiography of the head and neck on planning treatment of cervical spine fracture, if these tests were ordered appropriately, and to estimate cost and associated exposure to radiation and contrast medium. This retrospective review included all patients who underwent CT of the cervical spine and CT angiography of the head and neck from January 2010 to August 2011 at one institution. Patients were divided into those with and those without cervical spine fracture seen on CT of the cervical spine. We determined if the CT angiography of the head and neck was positive for vascular injury in the patients with a cervical fracture. Vascular injury treatment and alterations in surgical fracture treatment due to positive CT angiography of the head and neck were recorded. A scan was deemed appropriate if it had been ordered per established institutional protocol. Of the 381 patients who underwent CT angiography of the head and neck, 126 had a cervical injury. Sixteen of the CT angiography studies were appropriately ordered for non-spinal indications, and twenty-three were inappropriately ordered. The CT angiography was positive for one patient for whom the imaging was off protocol and one for whom the indication was non-spinal. Nineteen patients had positive CT angiography of the head and neck; no patient underwent surgical intervention for a vascular lesion. Eleven patients underwent surgical intervention for a cervical fracture; the operative plan was changed because of vascular injury in one case. The CT angiography was positive for eleven of forty-eight patients who had sustained a C2 fracture; this group accounted for eleven of the nineteen positive CT angiography studies. Noncontiguous injuries occurred in nineteen patients; three had positive CT angiography of the head and neck. The approximate charge for the CT angiography was $3925, radiation exposure was approximately 4000 mGy/cm, and contrast-medium load was approximately 100 mL. Positive CT angiography of the head and neck rarely altered surgical treatment of cervical spine injuries. This study supports the findings in the literature that C1-C3 spine injuries have an increased association with vertebral artery injury. CT angiography of the head and neck ordered off protocol had a low likelihood of being positive. Strict adherence to protocols for CT angiography of the head and neck can reduce costs and decrease unnecessary exposure to radiation and contrast medium. Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.
Evaluation of image registration in PET/CT of the liver and recommendations for optimized imaging.
Vogel, Wouter V; van Dalen, Jorn A; Wiering, Bas; Huisman, Henkjan; Corstens, Frans H M; Ruers, Theo J M; Oyen, Wim J G
2007-06-01
Multimodality PET/CT of the liver can be performed with an integrated (hybrid) PET/CT scanner or with software fusion of dedicated PET and CT. Accurate anatomic correlation and good image quality of both modalities are important prerequisites, regardless of the applied method. Registration accuracy is influenced by breathing motion differences on PET and CT, which may also have impact on (attenuation correction-related) artifacts, especially in the upper abdomen. The impact of these issues was evaluated for both hybrid PET/CT and software fusion, focused on imaging of the liver. Thirty patients underwent hybrid PET/CT, 20 with CT during expiration breath-hold (EB) and 10 with CT during free breathing (FB). Ten additional patients underwent software fusion of dedicated PET and dedicated expiration breath-hold CT (SF). The image registration accuracy was evaluated at the location of liver borders on CT and uncorrected PET images and at the location of liver lesions. Attenuation-correction artifacts were evaluated by comparison of liver borders on uncorrected and attenuation-corrected PET images. CT images were evaluated for the presence of breathing artifacts. In EB, 40% of patients had an absolute registration error of the diaphragm in the craniocaudal direction of >1 cm (range, -16 to 44 mm), and 45% of lesions were mispositioned >1 cm. In 50% of cases, attenuation-correction artifacts caused a deformation of the liver dome on PET of >1 cm. Poor compliance to breath-hold instructions caused CT artifacts in 55% of cases. In FB, 30% had registration errors of >1 cm (range, -4 to 16 mm) and PET artifacts were less extensive, but all CT images had breathing artifacts. As SF allows independent alignment of PET and CT, no registration errors or artifacts of >1 cm of the diaphragm occurred. Hybrid PET/CT of the liver may have significant registration errors and artifacts related to breathing motion. The extent of these issues depends on the selected breathing protocol and the speed of the CT scanner. No protocol or scanner can guarantee perfect image fusion. On the basis of these findings, recommendations were formulated with regard to scanner requirements, breathing protocols, and reporting.
CT vaginography: a new CT technique for imaging of upper and middle vaginal fistulas.
Botsikas, Diomidis; Pluchino, Nicola; Kalovidouri, Anastasia; Platon, Alexandra; Montet, Xavier; Dallenbach, Patrick; Poletti, Pierre-Alexandre
2017-05-01
Different types of vaginal fistulas is a relatively uncommon condition in the Western world but very frequent in developing countries. In the past, conventional vaginography was the radiological examination of choice for exploring this condition. CT and MRI are now both used for this purpose. Our objective was to test the feasibility and to explore the potential role of a new CT imaging technique implementing vaginal introitus obstruction and opacification of the vagina with iodine contrast agent, to show patency of a fistula. We describe the technical protocol of CT-vaginography as performed in Geneva University Hospitals, including vaginal catheterization with a Foley catheter and obstruction of the introitus by inflating the balloon of the catheter. We also report three cases of patients with suspected vaginal fistula who underwent CT-vaginography. The examinations were technically successful. In one patient, it revealed the presence of fistulous pathways from the vaginal fornix along the bilateral infected surgical prostheses. In a second patient, it showed a fistula between the vagina and the necrotic cavity of a recurrent cervical cancer. In a third patient, it proved the absence of a suspected vaginal fistula. CT-vaginography is a technically feasible CT protocol that provides anatomical and functional information on clinically suspected vaginal fistulas. Advances in knowledge: After the abandon of conventional vaginography in the era of transaxial imaging, the current modalities of imaging vaginal fistulas provide excellent anatomical detail but less functional information concerning the permeability of a vaginal fistulous pathway. We propose the use of CT-vaginography, a technical protocol that we describe in detail.
Sanchez, Sophie; Fernandez, Vincent; Pierce, Stephanie E; Tafforeau, Paul
2013-09-01
Propagation phase-contrast synchrotron radiation microtomography (PPC-SRμCT) has proved to be very successful for examining fossils. Because fossils range widely in taphonomic preservation, size, shape and density, X-ray computed tomography protocols are constantly being developed and refined. Here we present a 1-h procedure that combines a filtered high-energy polychromatic beam with long-distance PPC-SRμCT (sample to detector: 4-16 m) and an attenuation protocol normalizing the absorption profile (tested on 13-cm-thick and 5.242 g cm(-3) locally dense samples but applicable to 20-cm-thick samples). This approach provides high-quality imaging results, which show marked improvement relative to results from images obtained without the attenuation protocol in apparent transmission, contrast and signal-to-noise ratio. The attenuation protocol involves immersing samples in a tube filled with aluminum or glass balls in association with a U-shaped aluminum profiler. This technique therefore provides access to a larger dynamic range of the detector used for tomographic reconstruction. This protocol homogenizes beam-hardening artifacts, thereby rendering it effective for use with conventional μCT scanners.
Accuracy of Reduced-Dose Computed Tomography for Ureteral Stones in Emergency Department Patients
Moore, Christopher L.; Daniels, Brock; Ghita, Monica; Gunabushanam, Gowthaman; Luty, Seth; Molinaro, Annette M.; Singh, Dinesh; Gross, Cary P.
2016-01-01
Study objective Reduced-dose computed tomography (CT) scans have been recommended for diagnosis of kidney stone but are rarely used in the emergency department (ED) setting. Test characteristics are incompletely characterized, particularly in obese patients. Our primary outcome is to determine the sensitivity and specificity of a reduced-dose CT protocol for symptomatic ureteral stones, particularly those large enough to require intervention, using a protocol stratified by patient size. Methods This was a prospective, blinded observational study of 201 patients at an academic medical center. Consenting subjects underwent both regular- and reduced-dose CT, stratified into a high and low body mass index (BMI) protocol based on effective abdominal diameter. Reduced-dose CT scans were interpreted by radiologists blinded to regular-dose interpretations. Follow-up for outcome and intervention was performed at 90 days. Results CT scans with both regular and reduced doses were conducted for 201 patients, with 63% receiving the high BMI reduced-dose protocol. Ureteral stone was identified in 102 patients (50.7%) of those receiving regular-dose CT, with a ureteral stone greater than 5 mm identified in 26 subjects (12.9%). Sensitivity of the reduced-dose CT for any ureteral stone was 90.2% (95% confidence interval [CI] 82.3% to 95.0%), with a specificity of 99.0% (95% CI 93.7% to 100.0%). For stones greater than 5 mm, sensitivity was 100% (95% CI 85.0% to 100.0%). Reduced-dose CT identified 96% of patients who required intervention for ureteral stone within 90 days. Mean reduction in size-specific dose estimate was 18.6 milligray (mGy), from 21.7 mGy (SD 9.7) to 3.4 mGy (SD 0.9). Conclusion CT with substantial dose reduction was 90.2% (95% CI 82.3% to 95.0%) sensitive and 98.9% (95% CI 85.0% to 100.0%) specific for ureteral stones in ED patients with a wide range of BMIs. Reduced-dose CT was 96.0% (95% CI 80.5% to 99.3%) sensitive for ureteral stones requiring intervention within 90 days. PMID:25441242
Levin, Scott; Toerper, Matthew; Hamrock, Eric; Hinson, Jeremiah S; Barnes, Sean; Gardner, Heather; Dugas, Andrea; Linton, Bob; Kirsch, Tom; Kelen, Gabor
2018-05-01
Standards for emergency department (ED) triage in the United States rely heavily on subjective assessment and are limited in their ability to risk-stratify patients. This study seeks to evaluate an electronic triage system (e-triage) based on machine learning that predicts likelihood of acute outcomes enabling improved patient differentiation. A multisite, retrospective, cross-sectional study of 172,726 ED visits from urban and community EDs was conducted. E-triage is composed of a random forest model applied to triage data (vital signs, chief complaint, and active medical history) that predicts the need for critical care, an emergency procedure, and inpatient hospitalization in parallel and translates risk to triage level designations. Predicted outcomes and secondary outcomes of elevated troponin and lactate levels were evaluated and compared with the Emergency Severity Index (ESI). E-triage predictions had an area under the curve ranging from 0.73 to 0.92 and demonstrated equivalent or improved identification of clinical patient outcomes compared with ESI at both EDs. E-triage provided rationale for risk-based differentiation of the more than 65% of ED visits triaged to ESI level 3. Matching the ESI patient distribution for comparisons, e-triage identified more than 10% (14,326 patients) of ESI level 3 patients requiring up triage who had substantially increased risk of critical care or emergency procedure (1.7% ESI level 3 versus 6.2% up triaged) and hospitalization (18.9% versus 45.4%) across EDs. E-triage more accurately classifies ESI level 3 patients and highlights opportunities to use predictive analytics to support triage decisionmaking. Further prospective validation is needed. Copyright © 2017 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
Bianconi, Francesco; Fravolini, Mario Luca; Bello-Cerezo, Raquel; Minestrini, Matteo; Scialpi, Michele; Palumbo, Barbara
2018-04-01
We retrospectively investigated the prognostic potential (correlation with overall survival) of 9 shape and 21 textural features from non-contrast-enhanced computed tomography (CT) in patients with non-small-cell lung cancer. We considered a public dataset of 203 individuals with inoperable, histologically- or cytologically-confirmed NSCLC. Three-dimensional shape and textural features from CT were computed using proprietary code and their prognostic potential evaluated through four different statistical protocols. Volume and grey-level run length matrix (GLRLM) run length non-uniformity were the only two features to pass all four protocols. Both features correlated negatively with overall survival. The results also showed a strong dependence on the evaluation protocol used. Tumour volume and GLRLM run-length non-uniformity from CT were the best predictor of survival in patients with non-small-cell lung cancer. We did not find enough evidence to claim a relationship with survival for the other features. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
[Competence of triage nurses in hospital emergency departments].
Martínez-Segura, Estrella; Lleixà-Fortuño, Mar; Salvadó-Usach, Teresa; Solà-Miravete, Elena; Adell-Lleixà, Mireia; Chanovas-Borrás, Manel R; March-Pallarés, Gemma; Mora-López, Gerard
2017-06-01
To identify associations between sociodemographic characteristics variables and competence levels of triage nurses in hospital emergency departments. Descriptive, cross-sectional, multicenter study of triage nurses in hospital emergency departments in the southwestern area of Catalonia (Ebre River territory). We used an instrument for evaluating competencies (the COM_VA questionnaire) and recording sociodemographic variables (age, sex, total work experience, emergency department experience, training in critical patient care and triage) and perceived confidence when performing triage. We then analyzed the association between these variables and competency scores. Competency scores on the COM_VA questionnaire were significantly higher in nurses with training in critical patient care (P=.001) and triage (P=0.002) and in those with longer emergency department experience (P<.0001). Perceived confidence when performing triage increased with competency score (P<.0001) and training in critical patient care (P<.0001) and triage (P=.045). The competence of triage nurses and their perception of confidence when performing triage increases with emergency department experience and training.
Yousif, Khalid; Bebbington, Jane; Foley, Bernard
2005-01-01
To assess the impact of the change from the National Triage Scale (NTS) to the Australasian Triage Scale (ATS) within a hospital ED. A retrospective audit of consecutive adult patients attending the ED of Auckland Hospital from July to September 2001, during which patients were triaged according to the NTS, were compared with patients triaged according to the ATS during July to September 2002. In total, 8715 patients attended the department during July to September 2001 compared with 9047 patients during July to September 2002. There was a significant shift in the triage ratios with patient number increases of 28 and 24% in triage categories two and three, respectively, and decreases of 15 and 67% in categories four and five, respectively. The revision of the ATS has had a significant impact on the triage distribution of patients who present to ED. The change of distribution might have implications for meeting performance criteria and assessing casemix.
128 slice computed tomography dose profile measurement using thermoluminescent dosimeter
NASA Astrophysics Data System (ADS)
Salehhon, N.; Hashim, S.; Karim, M. K. A.; Ang, W. C.; Musa, Y.; Bahruddin, N. A.
2017-05-01
The increasing use of computed tomography (CT) in clinical practice marks the needs to understand the dose descriptor and dose profile. The purposes of the current study were to determine the CT dose index free-in-air (CTDIair) in 128 slice CT scanner and to evaluate the single scan dose profile (SSDP). Thermoluminescent dosimeters (TLD-100) were used to measure the dose profile of the scanner. There were three sets of CT protocols where the tube potential (kV) setting was manipulated for each protocol while the rest of parameters were kept constant. These protocols were based from routine CT abdominal examinations for male adult abdomen. It was found that the increase of kV settings made the values of CTDIair increased as well. When the kV setting was changed from 80 kV to 120 kV and from 120 kV to 140 kV, the CTDIair values were increased as much as 147.9% and 53.9% respectively. The highest kV setting (140 kV) led to the highest CTDIair value (13.585 mGy). The p-value of less than 0.05 indicated that the results were statistically different. The SSDP showed that when the kV settings were varied, the peak sharpness and height of Gaussian function profiles were affected. The full width at half maximum (FWHM) of dose profiles for all protocols were coincided with the nominal beam width set for the measurements. The findings of the study revealed much information on the characterization and performance of 128 slice CT scanner.
Near-Infrared Spectroscopy: A Promising Prehospital Tool for Management of Traumatic Brain Injury.
Peters, Joost; Van Wageningen, Bas; Hoogerwerf, Nico; Tan, Edward
2017-08-01
Introduction Early identification of traumatic brain injury (TBI) is essential. Near-infrared spectroscopy (NIRS) can be used in prehospital settings for non-invasive monitoring and the diagnosis of patients who may require surgical intervention. The handheld NIRS Infrascanner (InfraScan Inc.; Philadelphia, Pennsylvania USA) uses eight symmetrical scan points to detect intracranial bleeding. A scanner was tested in a physician-staffed helicopter Emergency Medical Service (HEMS). The results were compared with those obtained using in-hospital computed tomography (CT) scans. Scan time, ease-of-use, and change in treatment were scored. A total of 25 patients were included. Complete scans were performed in 60% of patients. In 15 patients, the scan was abnormal, and in one patient, the scan resulted in a treatment change. Compared with the results of CT scanning, the Infrascanner obtained a sensitivity of 93.3% and a specificity of 78.6%. Most patients had severe TBI with indication for transport to a trauma center prior to scanning. In one patient, the scan resulted in a treatment change. Evaluation of patients with less severe TBI is needed to support the usefulness of the Infrascanner as a prehospital triage tool. Promising results were obtained using the InfraScan NIRS device in prehospital screening for intracranial hematomas in TBI patients. High sensitivity and good specificity were found. Further research is necessary to determine the beneficial effects of enhanced prehospital screening on triage, survival, and quality of life in TBI patients. Peters J , Van Wageningen B , Hoogerwerf N , Tan E . Near-infrared spectroscopy: a promising prehospital tool for management of traumatic brain injury. Prehosp Disaster Med. 2017;32(4):414-418.
SU-E-P-03: Implementing a Low Dose Lung Screening CT Program Meeting Regulatory Requirements
DOE Office of Scientific and Technical Information (OSTI.GOV)
LaFrance, M; Marsh, S; O'Donnell, G
Purpose: To provide information pertaining to IROC Houston QA Center's (RPC) credentialing process for institutions participating in NCI-sponsored clinical trials. Purpose: Provide guidance to the Radiology Departments with the intent of implementing a Low Dose CT Screening Program using different CT Scanners with multiple techniques within the framework of the required state regulations. Method: State Requirements for the purpose of implementing a Low Dose CT Lung Protocol required working with the Radiology and Pulmonary Department in setting up a Low Dose Screening Protocol designed to reduce the radiation burden to the patients enrolled. Radiation dose measurements (CTDIvol) for various CTmore » manufacturers (Siemens16, Siemens 64, Philips 64, and Neusoft128) for three different weight based protocols. All scans were reviewed by the Radiologist. Prior to starting a low dose lung screening protocol, information had to be submitted to the state for approval. Performing a Healing Arts protocol requires extensive information. This not only includes name and address of the applicant but a detailed description of the disease, the x-ray examination and the population to be examined. The unit had to be tested by a qualified expert using the technique charts. The credentials of all the operators, the supervisors and the Radiologists had to be submitted to the state. Results: All the appropriate documentation was sent to the state for review. The measured results between the Low Dose Protocol versus the default Adult Chest Protocol showed that there was a dose reduction of 65% for small (100-150 lb.) patient, 75% for the Medium patient (151-250 lbs.), and a 55% reduction for the Large patient ( over 250 lbs.). Conclusion: Measured results indicated that the Low Dose Protocol indeed lowered the screening patient's radiation dose and the institution was able to submit the protocol to the State's regulators.« less
Comparative analysis of multiple-casualty incident triage algorithms.
Garner, A; Lee, A; Harrison, K; Schultz, C H
2001-11-01
We sought to retrospectively measure the accuracy of multiple-casualty incident (MCI) triage algorithms and their component physiologic variables in predicting adult patients with critical injury. We performed a retrospective review of 1,144 consecutive adult patients transported by ambulance and admitted to 2 trauma centers. Association between first-recorded out-of-hospital physiologic variables and a resource-based definition of severe injury appropriate to the MCI context was determined. The association between severe injury and Triage Sieve, Simple Triage and Rapid Treatment, modified Simple Triage and Rapid Treatment, and CareFlight Triage was determined in the patient population. Of the physiologic variables, the Motor Component of the Glasgow Coma Scale had the strongest association with severe injury, followed by systolic blood pressure. The differences between CareFlight Triage, Simple Triage and Rapid Treatment, and modified Simple Triage and Rapid Treatment were not dramatic, with sensitivities of 82% (95% confidence interval [CI] 75% to 88%), 85% (95% CI 78% to 90%), and 84% (95% CI 76% to 89%), respectively, and specificities of 96% (95% CI 94% to 97%), 86% (95% CI 84% to 88%), and 91% (95% CI 89% to 93%), respectively. Both forms of Triage Sieve were significantly poorer predictors of severe injury. Of the physiologic variables used in the triage algorithms, the Motor Component of the Glasgow Coma Scale and systolic blood pressure had the strongest association with severe injury. CareFlight Triage, Simple Triage and Rapid Treatment, and modified Simple Triage and Rapid Treatment had similar sensitivities in predicting critical injury in designated trauma patients, but CareFlight Triage had better specificity. Because patients in a true mass casualty situation may not be completely comparable with designated trauma patients transported to emergency departments in routine circumstances, the best triage instrument in this study may not be the best in an actual MCI. These findings must be validated prospectively before their accuracy can be confirmed.
Dewes, Patricia; Frellesen, Claudia; Scholtz, Jan-Erik; Fischer, Sebastian; Vogl, Thomas J; Bauer, Ralf W; Schulz, Boris
2016-06-01
To evaluate a novel tin filter-based abdominal CT protocol for urolithiasis in terms of image quality and CT dose parameters. 130 consecutive patients with suspected urolithiasis underwent non-enhanced CT with three different protocols: 48 patients (group 1) were examined at tin-filtered 150kV (150kV Sn) on a third-generation dual-source-CT, 33 patients were examined with automated kV-selection (110-140kV) based on the scout view on the same CT-device (group 2), and 49 patients were examined on a second-generation dual-source-CT (group 3) with automated kV-selection (100-140kV). Automated exposure control was active in all groups. Image quality was subjectively evaluated on a 5-point-likert-scale by two radiologists and interobserver agreement as well as signal-to-noise-ratio (SNR) was calculated. Dose-length-product (DLP) and volume CT dose index (CTDIvol) were compared. Image quality was rated in favour for the tin filter protocol with excellent interobserver agreement (ICC=0.86-0.91) and the difference reached statistical significance (p<0.001). SNR was significantly higher in group 1 and 2 compared to second-generation DSCT (p<0.001). On third-generation dual-source CT, there was no significant difference in SNR between the 150kV Sn and the automated kV selection protocol (p=0.5). The DLP of group 1 was 23% and 21% (p<0.002) lower in comparison to group 2 and 3, respectively. So was the CTDIvol of group 1 compared to group 2 (-36%) and 3 (-32%) (p<0.001). Additional shaping of a 150kV source spectrum by a tin filter substantially lowers patient exposure while improving image quality on un-enhanced abdominal computed tomography for urinary stone disease. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Kakkar, Chandan; Sripathi, Smiti; Parakh, Anushri; Shrivastav, Rajendra
2016-01-01
Introduction Urolithiasis is one of the major, recurring problem in young individuals and CT being the commonest diagnostic modality used. In order to reduce the radiation dose to the patient who are young and as stone formation is a recurring process; one of the simplest way would be, low dose CT along with tube current modulation. Aim Aim of this study was to compare the sensitivity and specificity of low dose (70mAs) with standard dose (250mAs) protocol in detecting urolithiasis and to define the tube current and mean effective patient dose by these protocols. Materials and Methods A prospective study was conducted in 200 patients over a period of 2 years with acute flank pain presentation. CT was performed in 100 cases with standard dose and another 100 with low dose protocol using tube current modulation. Sensitivity and specificity for calculus detection, percentage reduction of dose and tube current with low dose protocol was calculated. Results Urolithiasis was detected in 138 patients, 67 were examined by high dose and 71 were by low dose protocol. Sensitivity and Specificity of low dose protocol was 97.1% and 96.4% with similar results found in high BMI patients. Tube current modulation resulted in reduction of effective tube current by 12.17%. The mean effective patient dose for standard dose was 10.33 mSv whereas 2.92 mSv for low dose with 51.13–53.8% reduction in low dose protocol. Conclusion The study has reinforced that low-dose CT with tube current modulation is appropriate for diagnosis of urolithiasis with significant reduction in tube current and patient effective dose. PMID:27437322
Koteshwar, Prakashini; Kakkar, Chandan; Sripathi, Smiti; Parakh, Anushri; Shrivastav, Rajendra
2016-05-01
Urolithiasis is one of the major, recurring problem in young individuals and CT being the commonest diagnostic modality used. In order to reduce the radiation dose to the patient who are young and as stone formation is a recurring process; one of the simplest way would be, low dose CT along with tube current modulation. Aim of this study was to compare the sensitivity and specificity of low dose (70mAs) with standard dose (250mAs) protocol in detecting urolithiasis and to define the tube current and mean effective patient dose by these protocols. A prospective study was conducted in 200 patients over a period of 2 years with acute flank pain presentation. CT was performed in 100 cases with standard dose and another 100 with low dose protocol using tube current modulation. Sensitivity and specificity for calculus detection, percentage reduction of dose and tube current with low dose protocol was calculated. Urolithiasis was detected in 138 patients, 67 were examined by high dose and 71 were by low dose protocol. Sensitivity and Specificity of low dose protocol was 97.1% and 96.4% with similar results found in high BMI patients. Tube current modulation resulted in reduction of effective tube current by 12.17%. The mean effective patient dose for standard dose was 10.33 mSv whereas 2.92 mSv for low dose with 51.13-53.8% reduction in low dose protocol. The study has reinforced that low-dose CT with tube current modulation is appropriate for diagnosis of urolithiasis with significant reduction in tube current and patient effective dose.
Hwang, Jae-Yeon; Do, Kyung-Hyun; Yang, Dong Hyun; Cho, Young Ah; Yoon, Hye-Kyung; Lee, Jin Seong; Koo, Hyun Jung
2015-01-01
Abstract Children are at greater risk of radiation exposure than adults because the rapidly dividing cells of children tend to be more radiosensitive and they have a longer expected life time in which to develop potential radiation injury. Some studies have surveyed computed tomography (CT) radiation doses and several studies have established diagnostic reference levels according to patient age or body size; however, no survey of CT radiation doses with a large number of patients has yet been carried out in South Korea. The aim of the present study was to investigate the radiation dose in pediatric CT examinations performed throughout South Korea. From 512 CT (222 brain CT, 105 chest CT, and 185 abdominopelvic CT) scans that were referred to our tertiary hospital, a dose report sheet was available for retrospective analysis of CT scan protocols and dose, including the volumetric CT dose index (CTDIvol), dose-length product (DLP), effective dose, and size-specific dose estimates (SSDE). At 55.2%, multiphase CT was the most frequently performed protocol for abdominopelvic CT. Tube current modulation was applied most often in abdominopelvic CT and chest CT, accounting for 70.1% and 62.7%, respectively. Regarding the CT dose, the interquartile ranges of the CTDIvol were 11.1 to 22.5 (newborns), 16.6 to 39.1 (≤1 year), 14.6 to 41.7 (2–5 years), 23.5 to 44.1 (6–10 years), and 31.4 to 55.3 (≤15 years) for brain CT; 1.3 to 5.7 (≤1 year), 3.9 to 6.8 (2–5 years), 3.9 to 9.3 (6–10 years), and 7.7 to 13.8 (≤15 years) for chest CT; and 4.0 to 7.5 (≤1 year), 4.2 to 8.9 (2–5 years), 5.7 to 12.4 (6–10 years), and 7.6 to 16.6 (≤15 years) for abdominopelvic CT. The SSDE and CTDIvol were well correlated for patients <5 years old, whereas the CTDIvol was lower in patients ≥6 years old. Our study describes the various parameters and dosimetry metrics of pediatric CT in South Korea. The CTDIvol, DLP, and effective dose were generally lower than in German and UK surveys, except in certain age groups. PMID:26683922
Momentary fitting in a fluid environment: A grounded theory of triage nurse decision making.
Reay, Gudrun; Rankin, James A; Then, Karen L
2016-05-01
Triage nurses control access to the Emergency Department (ED) and make decisions about patient acuity, patient priority, and placement of the patient in the ED. Understanding the processes and strategies that triage nurses use to make decisions is therefore vital for patient safety and the operation of the ED. The aim of the current study was to generate a substantive grounded theory (GT) of decision making by emergency triage Registered Nurses (RNs). Data collection consisted of seven observations of the triage environment at three tertiary care hospitals where RNs conducted triage and twelve interviews with triage RNs. The data were analyzed by constant comparison in accordance with the classical GT method. In the resultant theory, Momentary Fitting in a Fluid Environment, triage is conceptualized as a process consisting of four categories, determining acuity, anticipating needs, managing space, and creating space. The findings indicate that triage RNs continually strive to achieve fit, while simultaneously considering the individual patient and the ED as a whole entity. Triage RNs require appropriately designed triage environments and computer technology that enable them to secure real time knowledge of the ED to maintain situation awareness. Copyright © 2015 Elsevier Ltd. All rights reserved.
Vassalou, Evangelia E; Raissaki, Maria; Magkanas, Eleftherios; Antoniou, Katerina M; Karantanas, Apostolos H
2017-12-01
To compare lung ultrasonography (US) in the sitting or supine positions and the lateral decubitus position, with regard to the feasibility, duration, patient convenience, and assessment of B-lines, in patients with idiopathic pulmonary fibrosis. Twenty consecutive patients with idiopathic pulmonary fibrosis were prospectively enrolled. Lung US included scanning of 56 intercostal spaces. Each patient was examined twice by 2 protocols. During protocol 1, patients were examined in the supine and sitting positions for the anterior and dorsal chest, respectively. During protocol 2, patients were examined in the left lateral decubitus position for the evaluation of the right hemithorax and the reverse. Total, anterior, and posterior US scores resulted from the sum of B-lines at the whole, anterior, and posterior chest, respectively. High-resolution computed tomography (CT) was considered the reference standard. The duration of each protocol was recorded. Patients were questioned about which protocol they preferred. There was no difference regarding feasibility between the protocols. A significant correlation was found between total US scores for both protocols and high-resolution CT findings (P < .0001), with protocol 2 showing a slightly higher correlation. A positive correlation was found between the protocols regarding total, anterior, and posterior US scores (P < .0001). The mean duration of protocol 2 was less than that of protocol 1 (P < .005). Nineteen patients (95%) reported a preference for protocol 2. Lung US in the lateral decubitus position seems to be faster and more convenient. There appears to be no difference regarding feasibility and the number of B-lines, whereas it shows slightly higher correlation with high-resolution CT, compared with the sitting or supine positions in patients with idiopathic pulmonary fibrosis. © 2017 by the American Institute of Ultrasound in Medicine.
Lee, Soo Jin; Paeng, Jin Chul; Goo, Jin Mo; Lee, Jeong Min; Cheon, Gi Jeong; Lee, Dong Soo; Chung, June-Key; Kang, Keon Wook
2017-04-01
The purpose of this study was to compare quantitative indexes for fluorine-18 fluorodeoxyglucose uptake and metabolic volume between PET/MRI and PET/CT. Sixty-six patients with solid tumors (32 with lung cancer and 34 with pancreatic cancer) who underwent sequential fluorine-18 fluorodeoxyglucose PET/MRI and PET/CT were retrospectively enrolled. On PET images, maximum and peak standardized uptake values (SUVmax and SUVpeak, respectively), and maximum tumor-to-liver ratio (TLRmax) were measured. Metabolic tumor volume (MTV) and total-lesion glycolysis (TLG) with margin thresholds of 50% SUVmax and SUV 2.5 (MTV50%, MTV2.5; TLG50%, TLG2.5, respectively) were compared between PET/MRI and PET/CT, with patients classified into two groups using imaging protocol (the PET/MRI-first and PET/CT-first groups). There were significant correlations of all tested indexes between PET/MRI and PET/CT (r=0.867-0.987, P<0.001). SUVmax and SUVpeak were lower on PET/MRI regardless of imaging protocol (P<0.001 in the PET/MRI-first group). In contrast, TLRmax exhibited reverse results between the PET/MRI-first and PET/CT-first groups. MTV50% and TLG values varied between PET/MRI and PET/CT, as well as between the PET/MRI-first and PET/CT-first groups. However, MTV2.5 was relatively robust against imaging protocol and modality. There are significant correlations of the quantitative indexes between PET/MRI and PET/CT. However, uptake indexes of SUVmax and SUVpeak are lower on PET/MRI than on PET/CT, and volumetric indexes of MTV50% and TLG values also exhibited significant differences. It may be suggested that TLRmax and MTV2.5 are relatively more appropriate indexes than others when PET/MRI and PET/CT are used interchangeably.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Persson, Mats, E-mail: mats.persson@mi.physics.kth
Purpose: The highest photon fluence rate that a computed tomography (CT) detector must be able to measure is an important parameter. The authors calculate the maximum transmitted fluence rate in a commercial CT scanner as a function of patient size for standard head, chest, and abdomen protocols. Methods: The authors scanned an anthropomorphic phantom (Kyoto Kagaku PBU-60) with the reference CT protocols provided by AAPM on a GE LightSpeed VCT scanner and noted the tube current applied with the tube current modulation (TCM) system. By rescaling this tube current using published measurements on the tube current modulation of a GEmore » scanner [N. Keat, “CT scanner automatic exposure control systems,” MHRA Evaluation Report 05016, ImPACT, London, UK, 2005], the authors could estimate the tube current that these protocols would have resulted in for other patient sizes. An ECG gated chest protocol was also simulated. Using measured dose rate profiles along the bowtie filters, the authors simulated imaging of anonymized patient images with a range of sizes on a GE VCT scanner and calculated the maximum transmitted fluence rate. In addition, the 99th and the 95th percentiles of the transmitted fluence rate distribution behind the patient are calculated and the effect of omitting projection lines passing just below the skin line is investigated. Results: The highest transmitted fluence rates on the detector for the AAPM reference protocols with centered patients are found for head images and for intermediate-sized chest images, both with a maximum of 3.4 ⋅ 10{sup 8} mm{sup −2} s{sup −1}, at 949 mm distance from the source. Miscentering the head by 50 mm downward increases the maximum transmitted fluence rate to 5.7 ⋅ 10{sup 8} mm{sup −2} s{sup −1}. The ECG gated chest protocol gives fluence rates up to 2.3 ⋅ 10{sup 8} − 3.6 ⋅ 10{sup 8} mm{sup −2} s{sup −1} depending on miscentering. Conclusions: The fluence rate on a CT detector reaches 3 ⋅ 10{sup 8} − 6 ⋅ 10{sup 8} mm{sup −2} s{sup −1} in standard imaging protocols, with the highest rates occurring for ECG gated chest and miscentered head scans. These results will be useful to developers of CT detectors, in particular photon counting detectors.« less
Giesen, Paul; Ferwerda, Rosa; Tijssen, Roelie; Mokkink, Henk; Drijver, Roeland; van den Bosch, Wil; Grol, Richard
2007-06-01
In recent years, there has been a growth in the use of triage nurses to decrease general practitioner (GP) workloads and increase the efficiency of telephone triage. The actual safety of decisions made by triage nurses has not yet been assessed. To investigate whether triage nurses accurately estimate the urgency level of health complaints when using the national telephone guidelines, and to examine the relationship between the performance of triage nurses and their education and training. A cross-sectional, multicentre, observational study employing five mystery (simulated) patients who telephoned triage nurses in four GP cooperatives. The mystery patients played standardised roles. Each role had one of four urgency levels as determined by experts. The triage nurses called were asked to estimate the level of urgency after the contact. This level of urgency was compared with a gold standard. Triage nurses estimated the level of urgency of 69% of the 352 contacts correctly and underestimated the level of urgency of 19% of the contacts. The sensitivity and specificity of the urgency estimates provided by the triage nurses were found to be 0.76 and 0.95, respectively. The positive and negative predictive values of the urgency estimates were 0.83 and 0.93, respectively. A significant correlation was found between correct estimation of urgency and specific training on the use of the guidelines. The educational background (primary or secondary care) of the nurses had no significant relationship with the rate of underestimation. Telephone triage by triage nurses is efficient but possibly not safe, with potentially severe consequences for the patient. An educational programme for triage nurses is recommended. Also, a direct second safety check of all cases by a specially trained GP telephone doctor is advisable.
Giesen, Paul; Ferwerda, Rosa; Tijssen, Roelie; Mokkink, Henk; Drijver, Roeland; van den Bosch, Wil; Grol, Richard
2007-01-01
Background In recent years, there has been a growth in the use of triage nurses to decrease general practitioner (GP) workloads and increase the efficiency of telephone triage. The actual safety of decisions made by triage nurses has not yet been assessed. Objectives To investigate whether triage nurses accurately estimate the urgency level of health complaints when using the national telephone guidelines, and to examine the relationship between the performance of triage nurses and their education and training. Method A cross‐sectional, multicentre, observational study employing five mystery (simulated) patients who telephoned triage nurses in four GP cooperatives. The mystery patients played standardised roles. Each role had one of four urgency levels as determined by experts. The triage nurses called were asked to estimate the level of urgency after the contact. This level of urgency was compared with a gold standard. Results Triage nurses estimated the level of urgency of 69% of the 352 contacts correctly and underestimated the level of urgency of 19% of the contacts. The sensitivity and specificity of the urgency estimates provided by the triage nurses were found to be 0.76 and 0.95, respectively. The positive and negative predictive values of the urgency estimates were 0.83 and 0.93, respectively. A significant correlation was found between correct estimation of urgency and specific training on the use of the guidelines. The educational background (primary or secondary care) of the nurses had no significant relationship with the rate of underestimation. Conclusion Telephone triage by triage nurses is efficient but possibly not safe, with potentially severe consequences for the patient. An educational programme for triage nurses is recommended. Also, a direct second safety check of all cases by a specially trained GP telephone doctor is advisable. PMID:17545343
Nagayama, Yasunori; Nakaura, Takeshi; Oda, Seitaro; Utsunomiya, Daisuke; Funama, Yoshinori; Iyama, Yuji; Taguchi, Narumi; Namimoto, Tomohiro; Yuki, Hideaki; Kidoh, Masafumi; Hirata, Kenichiro; Nakagawa, Masataka; Yamashita, Yasuyuki
2018-04-01
To evaluate the image quality and lesion conspicuity of virtual-monochromatic-imaging (VMI) with dual-layer DECT (DL-DECT) for reduced-iodine-load multiphasic-hepatic CT. Forty-five adults with renal dysfunction who had undergone hepatic DL-DECT with 300-mgI/kg were included. VMI (40-70-keV, DL-DECT-VMI) was generated at each enhancement phase. As controls, 45 matched patients undergoing standard 120-kVp protocol (120-kVp, 600-mgI/kg, and iterative reconstruction) were included. We compared the size-specific dose estimate (SSDE), image noise, CT attenuation, and contrast-to-noise ratio (CNR) between protocols. Two radiologists scored the image quality and lesion conspicuity. SSDE was significantly lower in DL-DECT group (p < 0.01). Image noise of DL-DECT-VMI was almost constant at each keV (differences of ≤15%) and equivalent to or lower than of 120-kVp. As the energy decreased, CT attenuation and CNR gradually increased; the values of 55-60 keV images were almost equivalent to those of standard 120-kVp. The highest scores for overall quality and lesion conspicuity were assigned at 40-keV followed by 45 to 55-keV, all of which were similar to or better than of 120-kVp. For multiphasic-hepatic CT with 50% iodine-load, DL-DECT-VMI at 40- to 55-keV provides equivalent or better image quality and lesion conspicuity without increasing radiation dose compared with standard 120-kVp protocol. • 40-55-keV yields optimal image quality for half-iodine-load multiphasic-hepatic CT with DL-DECT. • DL-DECT protocol decreases radiation exposure compared with 120-kVp scans with iterative reconstruction. • 40-keV images maximise conspicuity of hepatocellular carcinoma especially at hepatic-arterial phase.
Wood, Tim J; Moore, Craig S; Horsfield, Carl J; Saunderson, John R; Beavis, Andrew W
2015-01-01
The purpose of this study was to develop size-based radiotherapy kilovoltage cone beam CT (CBCT) protocols for the pelvis. Image noise was measured in an elliptical phantom of varying size for a range of exposure factors. Based on a previously defined "small pelvis" reference patient and CBCT protocol, appropriate exposure factors for small, medium, large and extra-large patients were derived which approximate the image noise behaviour observed on a Philips CT scanner (Philips Medical Systems, Best, Netherlands) with automatic exposure control (AEC). Selection criteria, based on maximum tube current-time product per rotation selected during the radiotherapy treatment planning scan, were derived based on an audit of patient size. It has been demonstrated that 110 kVp yields acceptable image noise for reduced patient dose in pelvic CBCT scans of small, medium and large patients, when compared with manufacturer's default settings (125 kVp). Conversely, extra-large patients require increased exposure factors to give acceptable images. 57% of patients in the local population now receive much lower radiation doses, whereas 13% require higher doses (but now yield acceptable images). The implementation of size-based exposure protocols has significantly reduced radiation dose to the majority of patients with no negative impact on image quality. Increased doses are required on the largest patients to give adequate image quality. The development of size-based CBCT protocols that use the planning CT scan (with AEC) to determine which protocol is appropriate ensures adequate image quality whilst minimizing patient radiation dose.
Sharp, Adam L.; Huang, Brian Z.; Tang, Tania; Shen, Ernest; Melnick, Edward R.; Venkatesh, Arjun K.; Kanter, Michael H.; Gould, Michael K.
2018-01-01
Study objective Approximately 1 in 3 computed tomography (CT) scans performed for head injury may be avoidable. We evaluate the association of implementation of the Canadian CT Head Rule on head CT imaging in community emergency departments (EDs). Methods We conducted an interrupted time-series analysis of encounters from January 2014 to December 2015 in 13 Southern California EDs. Adult health plan members with a trauma diagnosis and Glasgow Coma Scale score at ED triage were included. A multicomponent intervention included clinical leadership endorsement, physician education, and integrated clinical decision support. The primary outcome was the proportion of patients receiving a head CT. The unit of analysis was ED encounter, and we compared CT use pre- and postintervention with generalized estimating equations segmented logistic regression, with physician as a clustering variable. Secondary analysis described the yield of identified head injuries pre- and postintervention. Results Included were 44,947 encounters (28,751 preintervention and 16,196 postintervention), resulting in 14,633 (32.6%) head CTs (9,758 preintervention and 4,875 postintervention), with an absolute 5.3% (95% confidence interval [CI] 2.5% to 8.1%) reduction in CT use postintervention. Adjusted pre-post comparison showed a trend in decreasing odds of imaging (odds ratio 0.98; 95% CI 0.96 to 0.99). All but one ED reduced CTs postintervention (0.3% to 8.7%, one ED 0.3% increase), but no interaction between the intervention and study site over time existed (P=.34). After the intervention, diagnostic yield of CT-identified intracranial injuries increased by 2.3% (95% CI 1.5% to 3.1%). Conclusion A multicomponent implementation of the Canadian CT Head Rule was associated with a modest reduction in CT use and an increased diagnostic yield of head CTs for adult trauma encounters in community EDs. PMID:28739290
Quantitative image feature variability amongst CT scanners with a controlled scan protocol
NASA Astrophysics Data System (ADS)
Ger, Rachel B.; Zhou, Shouhao; Chi, Pai-Chun Melinda; Goff, David L.; Zhang, Lifei; Lee, Hannah J.; Fuller, Clifton D.; Howell, Rebecca M.; Li, Heng; Stafford, R. Jason; Court, Laurence E.; Mackin, Dennis S.
2018-02-01
Radiomics studies often analyze patient computed tomography (CT) images acquired from different CT scanners. This may result in differences in imaging parameters, e.g. different manufacturers, different acquisition protocols, etc. However, quantifiable differences in radiomics features can occur based on acquisition parameters. A controlled protocol may allow for minimization of these effects, thus allowing for larger patient cohorts from many different CT scanners. In order to test radiomics feature variability across different CT scanners a radiomics phantom was developed with six different cartridges encased in high density polystyrene. A harmonized protocol was developed to control for tube voltage, tube current, scan type, pitch, CTDIvol, convolution kernel, display field of view, and slice thickness across different manufacturers. The radiomics phantom was imaged on 18 scanners using the control protocol. A linear mixed effects model was created to assess the impact of inter-scanner variability with decomposition of feature variation between scanners and cartridge materials. The inter-scanner variability was compared to the residual variability (the unexplained variability) and to the inter-patient variability using two different patient cohorts. The patient cohorts consisted of 20 non-small cell lung cancer (NSCLC) and 30 head and neck squamous cell carcinoma (HNSCC) patients. The inter-scanner standard deviation was at least half of the residual standard deviation for 36 of 49 quantitative image features. The ratio of inter-scanner to patient coefficient of variation was above 0.2 for 22 and 28 of the 49 features for NSCLC and HNSCC patients, respectively. Inter-scanner variability was a significant factor compared to patient variation in this small study for many of the features. Further analysis with a larger cohort will allow more thorough analysis with additional variables in the model to truly isolate the interscanner difference.
Sabarudin, Akmal; Sun, Zhonghua; Yusof, Ahmad Khairuddin Md
2013-09-30
This study is conducted to investigate and compare image quality and radiation dose between prospective ECG-triggered and retrospective ECG-gated coronary CT angiography (CCTA) with the use of single-source CT (SSCT) and dual-source CT (DSCT). A total of 209 patients who underwent CCTA with suspected coronary artery disease scanned with SSCT (n=95) and DSCT (n=114) scanners using prospective ECG-triggered and retrospective ECG-gated protocols were recruited from two institutions. The image was assessed by two experienced observers, while quantitative assessment was performed by measuring the image noise, the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR). Effective dose was calculated using the latest published conversion coefficient factor. A total of 2087 out of 2880 coronary artery segments were assessable, with 98.0% classified as of sufficient and 2.0% as of insufficient image quality for clinical diagnosis. There was no significant difference in overall image quality between prospective ECG-triggered and retrospective gated protocols, whether it was performed with DSCT or SSCT scanners. Prospective ECG-triggered protocol was compared in terms of radiation dose calculation between DSCT (6.5 ± 2.9 mSv) and SSCT (6.2 ± 1.0 mSv) scanners and no significant difference was noted (p=0.99). However, the effective dose was significantly lower with DSCT (18.2 ± 8.3 mSv) than with SSCT (28.3 ± 7.0 mSv) in the retrospective gated protocol. Prospective ECG-triggered CCTA reduces radiation dose significantly compared to retrospective ECG-gated CCTA, while maintaining good image quality. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Barateau, Anaïs; Garlopeau, Christopher; Cugny, Audrey; De Figueiredo, Bénédicte Henriques; Dupin, Charles; Caron, Jérôme; Antoine, Mikaël
2015-03-01
We aimed to identify the most accurate combination of phantom and protocol for image value to density table (IVDT) on volume-modulated arc therapy (VMAT) dose calculation based on kV-Cone-beam CT imaging, for head and neck (H&N) and pelvic localizations. Three phantoms (Catphan(®)600, CIRS(®)062M (inner phantom for head and outer phantom for body), and TomoTherapy(®) "Cheese" phantom) were used to create IVDT curves of CBCT systems with two different CBCT protocols (Standard-dose Head and Standard Pelvis). Hounsfield Unit (HU) time stability and repeatability for a single On-Board-Imager (OBI) and compatibility of two distinct devices were assessed with Catphan(®)600. Images from the anthropomorphic phantom CIRS ATOM(®) for both CT and CBCT modalities were used for VMAT dose calculation from different IVDT curves. Dosimetric indices from CT and CBCT imaging were compared. IVDT curves from CBCT images were highly different depending on phantom used (up to 1000 HU for high densities) and protocol applied (up to 200 HU for high densities). HU time stability was verified over seven weeks. A maximum difference of 3% on the dose calculation indices studied was found between CT and CBCT VMAT dose calculation across the two localizations using appropriate IVDT curves. One IVDT curve per localization can be established with a bi-monthly verification of IVDT-CBCT. The IVDT-CBCTCIRS-Head phantom with the Standard-dose Head protocol was the most accurate combination for dose calculation on H&N CBCT images. For pelvic localizations, the IVDT-CBCTCheese established with the Standard Pelvis protocol provided the best accuracy. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Sibille, Louis; Chambert, Benjamin; Alonso, Sandrine; Barrau, Corinne; D'Estanque, Emmanuel; Al Tabaa, Yassine; Collombier, Laurent; Demattei, Christophe; Kotzki, Pierre-Olivier; Boudousq, Vincent
2016-07-01
The purpose of this study was to compare a routine bone SPECT/CT protocol using CT reconstructed with filtered backprojection (FBP) with an optimized protocol using low-dose CT images reconstructed with adaptive statistical iterative reconstruction (ASiR). In this prospective study, enrolled patients underwent bone SPECT/CT, with 1 SPECT acquisition followed by 2 randomized CT acquisitions: FBP CT (FBP; noise index, 25) and ASiR CT (70% ASiR; noise index, 40). The image quality of both attenuation-corrected SPECT and CT images was visually (5-point Likert scale, 2 interpreters) and quantitatively (contrast ratio [CR] and signal-to-noise ratio [SNR]) estimated. The CT dose index volume, dose-length product, and effective dose were compared. Seventy-five patients were enrolled in the study. Quantitative attenuation-corrected SPECT evaluation showed no inferiority for contrast ratio and SNR issued from FBP CT or ASiR CT (respectively, 13.41 ± 7.83 vs. 13.45 ± 7.99 and 2.33 ± 0.83 vs. 2.32 ± 0.84). Qualitative image analysis showed no difference between attenuation-corrected SPECT images issued from FBP CT or ASiR CT for both interpreters (respectively, 3.5 ± 0.6 vs. 3.5 ± 0.6 and 3.6 ± 0.5 vs. 3.6 ± 0.5). Quantitative CT evaluation showed no inferiority for SNR between FBP and ASiR CT images (respectively, 0.93 ± 0.16 and 1.07 ± 0.17). Qualitative image analysis showed no quality difference between FBP and ASiR CT images for both interpreters (respectively, 3.8 ± 0.5 vs. 3.6 ± 0.5 and 4.0 ± 0.1 vs. 4.0 ± 0.2). Mean CT dose index volume, dose-length product, and effective dose for ASiR CT (3.0 ± 2.0 mGy, 148 ± 85 mGy⋅cm, and 2.2 ± 1.3 mSv) were significantly lower than for FBP CT (8.5 ± 3.7 mGy, 365 ± 160 mGy⋅cm, and 5.5 ± 2.4 mSv). The use of 70% ASiR blending in bone SPECT/CT can reduce the CT radiation dose by 60%, with no sacrifice in attenuation-corrected SPECT and CT image quality, compared with the conventional protocol using FBP CT reconstruction technique. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.
Kim, Jane J; Wright, Thomas C; Goldie, Sue J
2005-06-15
European countries with established cytology-based screening programs for cervical cancer will soon face decisions about whether to incorporate human papillomavirus (HPV) DNA testing and what strategies will be most cost-effective. We assessed the cost-effectiveness of incorporating HPV DNA testing into existing cervical cancer screening programs in the United Kingdom, The Netherlands, France, and Italy. We created a computer-based model of the natural history of cervical carcinogenesis for each using country-specific data on cervical cancer risk and compared each country's current screening policy with two new strategies: 1) cytology throughout a woman's lifetime, using HPV DNA testing as a triage strategy for equivocal cytology results ("HPV triage"), as well as 2) cytology until age 30 years and HPV DNA testing in combination with cytology in women more than 30 years of age ("combination testing"). Outcomes included reduction in lifetime cervical cancer risk, increase in life expectancy, lifetime costs, and incremental cost-effectiveness ratios, expressed as cost per year of life saved. We explored alternative protocols and conducted sensitivity analysis on key parameters of the model over a relevant range of values to identify the most cost-effective options for each country. Both HPV DNA testing strategies, HPV triage and combination testing, were more effective than each country's status quo screening policy. Incremental cost-effectiveness ratios for HPV triage were less than $13,000 per year of life saved, whereas those for combination testing ranged from $9800 to $75,900 per year of life saved, depending on screening interval. We identified options that would be very cost-effective (i.e., cost-effectiveness ratio less than the gross domestic product per capita) in each of the four countries. HPV DNA testing has the potential to improve health benefits at a reasonable cost compared with current screening policies in four European countries.
Mahajan, Vidushi; Arora, Sumant; Kaur, Tarundeep; Gupta, Sorab; Guglani, Vishal
2013-01-01
Background: The 23-hour Observation Unit (OU) is a novel and an effective means for tackling overcrowding in busy Paediatric Emergency Departments (PED) worldwide. However, unexpected hospitalisations in the OU involve transfer of care and they reduce the efficiency of the OU. Hence, we aimed to study the presenting diagnoses which were responsible for the unexpected hospitalisations in a 23-hour OU. Methods and Design: A prospective cohort study Setting: The PED at a tertiary care teaching hospital. Duration: 15th Feb-15th March 2011. Protocol: Consecutive children were triaged at presentation to the PED, according to the WHO paediatric emergency triage algorithm. Those who were transferred to the 23-hour OU, were further followed up for duration of the stay, the hospital course, and the outcome (discharge/hospitalisation). Results: Three hundred (228 males, 72 females) consecutive children who attended the PED over one month were enrolled. All the children, at presentation, were triaged by the medical intern/s who was/were posted in the PED, and they were crosschecked by a PED consultant. A majority (55%, n=165) of the children were triaged as non-urgent, 32% (n=97) as priority and 13% (n=38) as emergent. Out of the 300 children, 173(58%) were transferred to the 23-hour OU. Of these, 16 (9.1%) required unexpected hospitalisations. The children who required hospitalisations had the following diagnoses: bronchiolitis (4), bronchopneumonia (4), seizure (2), viral hepatitis (2), high fever (1), bronchial asthma (1), severe anaemia (1), and urticaria (1). The mean duration of the stay in the OU was 19 hours for those who needed hospitalisation, as against 13 hours for those who were discharged from the OU. Conclusion: The children with respiratory complaints (bronchiolitis and bronchopneumonia) need frequent monitoring in the 23-hour OU, as they have high hospitalisation rates in the OU. PMID:23998079
Wood, T J; Moore, C S; Stephens, A; Saunderson, J R; Beavis, A W
2015-09-01
Given the increasing use of computed tomography (CT) in the UK over the last 30 years, it is essential to ensure that all imaging protocols are optimised to keep radiation doses as low as reasonably practicable, consistent with the intended clinical task. However, the complexity of modern CT equipment can make this task difficult to achieve in practice. Recent results of local patient dose audits have shown discrepancies between two Philips CT scanners that use the DoseRight 2.0 automatic exposure control (AEC) system in the 'automatic' mode of operation. The use of this system can result in drifting dose and image quality performance over time as it is designed to evolve based on operator technique. The purpose of this study was to develop a practical technique for configuring examination protocols on four CT scanners that use the DoseRight 2.0 AEC system in the 'manual' mode of operation. This method used a uniform phantom to generate reference images which form the basis for how the AEC system calculates exposure factors for any given patient. The results of this study have demonstrated excellent agreement in the configuration of the CT scanners in terms of average patient dose and image quality when using this technique. This work highlights the importance of CT protocol harmonisation in a modern Radiology department to ensure both consistent image quality and radiation dose. Following this study, the average radiation dose for a range of CT examinations has been reduced without any negative impact on clinical image quality.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Flores-M, E.; Gamboa de Buen, I.; Buenfil, A. E.
Computed Tomography (CT) is a high dose X ray imaging procedure and its use has rapidly increased in the last two decades fueled by the development of helical CT. The aim of this study is to present values of the dosimetric quantities for CT paediatric examinations of thoracic and abdominal regions. The protocols studied were those of chest, lung-mediastine, chest-abdomen, pulmonary high resolution and mediastine-abdomen, which are the more common examinations performed at ''Hospital Infantil de Mexico Federico Gomez'' in the thoracic-abdominal region. The measurements were performed on a Siemens SOMATOM Sensation 16 CT Scanner and the equipment used wasmore » a CT pencil ionization chamber, connected to an electrometer. This system was calibrated for RQT9 CT beam quality. A PMMA head phantom with diameter of 16 cm and length of 15 cm was also used. The dosimetric quantities measured were the weighted air kerma index (C{sub w}), the volumetric dose index (C{sub vol}) and the CT air kerma-length product. It was found that the pulmonary high resolution examination presented the highest values for the C{sub w}(31.1 mGy) and C{sub vol}(11.1 mGy). The examination with the lowest values of these two quantities was the chest-abdomen protocol with 10.5 mGy for C{sub w} and 5.5 mGy for C{sub vol}. However, this protocol presented the highest value for P{sub KL,CT}(282.2 mGy cm) when considering the average clinical length of the examinations.« less
Detterbeck, Andreas; Hofmeister, Michael; Hofmann, Elisabeth; Haddad, Daniel; Weber, Daniel; Hölzing, Astrid; Zabler, Simon; Schmid, Matthias; Hiller, Karl-Heinz; Jakob, Peter; Engel, Jens; Hiller, Jochen; Hirschfelder, Ursula
2016-07-01
To examine the relative usefulness and suitability of magnetic resonance imaging (MRI) in daily clinical practice as compared to various technologies of computed tomography (CT) in addressing questions of orthodontic interest. Three blinded raters evaluated 2D slices and 3D reconstructions created from scans of two pig heads. Five imaging modalities were used, including three CT technologies-multislice (MSCT), cone-beam CT (CBCT), and industrial (µCT)-and two MRI protocols with different scan durations. Defined orthodontic parameters were rated one by one on the 2D slices and the 3D reconstructions, followed by final overall ratings for each modality. A mixed linear model was used for statistical analysis. Based on the 2D slices, the parameter of visualizing tooth-germ topography did not yield any significantly different ratings for MRI versus any of the CT scans. While some ratings for the other parameters did involve significant differences, how these should be interpreted depends greatly on the relevance of each parameter. Based on the 3D reconstructions, the only significant difference between technologies was noted for the parameter of visualizing root-surface morphology. Based on the final overall ratings, the imaging performance of the standard MRI protocol was noninferior to the performance of the three CT technologies. On comparing the imaging performance of MRI and CT scans, it becomes clear that MRI has a huge potential for applications in daily clinical practice. Given its additional benefits of a good contrast ratio and complete absence of ionizing radiation, further studies are needed to explore this clinical potential in greater detail.
NASA Astrophysics Data System (ADS)
Alshipli, Marwan; Kabir, Norlaili A.
2017-05-01
Computed tomography (CT) employs X-ray radiation to create cross-sectional images. Dual-energy CT acquisition includes the images acquired from an alternating voltage of X-ray tube: a low- and a high-peak kilovoltage. The main objective of this study is to determine the best slice thickness that reduces image noise with adequate diagnostic information using dual energy CT head protocol. The study used the ImageJ software and statistical analyses to aid the medical image analysis of dual-energy CT. In this study, ImageJ software and F-test were utilised as the combination methods to analyse DICOM CT images. They were used to investigate the effect of slice thickness on noise and visibility in dual-energy CT head protocol images. Catphan-600 phantom was scanned at different slice thickness values;.6, 1, 2, 3, 4, 5 and 6 mm, then quantitative analyses were carried out. The DECT operated in helical mode with another fixed scan parameter values. Based on F-test statistical analyses, image noise at 0.6, 1, and 2 mm were significantly different compared to the other images acquired at slice thickness of 3, 4, 5, and 6 mm. However, no significant differences of image noise were observed at 3, 4, 5, and 6 mm. As a result, better diagnostic image value, image visibility, and lower image noise in dual-energy CT head protocol was observed at a slice thickness of 3 mm.
Bombings specific triage (Bost Tool) tool and its application by healthcare professionals.
Sanjay, Jaiswal; Ankur, Verma; Tamorish, Kole
2015-01-01
Bombing is a unique incident which produces unique patterns, multiple and occult injuries. Death often is a result of combined blast, ballistic and thermal effect injuries. Various natures of injury, self referrals and arrival by private transportation may lead to "wrong triage" in the emergency department. In India there has been an increase in incidence of bombing in the last 15 years. There is no documented triage tool from the National Disaster Management Authority of India for Bombings. We have tried to develop an ideal bombing specific triage tool which will guide the right patients to the right place at the right time and save more lives. There are three methods of studying the triage tool: 1) real disaster; 2) mock drill; 3) table top exercise. In this study, a table top exercise method was selected. There are two groups, each consisting of an emergency physician, a nurse and a paramedic. By using the proportion test, we found that correct triaging was significantly different (P=0.005) in proportion between the two groups: group B (80%) with triage tool performed better in triaging the bomb blast victims than group A (50%) without the bombing specific triage tool performed. Development of bombing specific triage tool can reduce under triaging.
Triage level assignment and nurse characteristics and experience.
Gómez-Angelats, Elisenda; Miró, Òscar; Bragulat Baur, Ernesto; Antolín Santaliestra, Alberto; Sánchez Sánchez, Miquel
2018-06-01
To study the relation between nursing staff demographics and experience and their assignment of triage level in the emergency department. One-year retrospective observational study in the triage area of a tertiary care urban university hospital that applies the Andorran-Spanish triage model. Variables studied were age, gender, nursing experience, triage experience, shift, usual level of emergency work the nurse undertakes, number of triage decisions made, and percentage of patients assigned to each level. Fifty nurses (5 men, 45 women) with a mean (SD) age of 45 (9) years triaged 67 803 patients during the year. Nurses classified more patients in level 5 on the morning shift (7.9%) than on the afternoon shift (5.5%) (P=.003). The difference in the rate of level-5 triage classification became significant when nurses were older (β = 0.092, P=.037) and experience was greater (β = 0.103, P=.017). The number of triages recorded by a nurse was significantly and directly related to the percentage of patients assigned to level 3 (β = 0.003, P=.006) and inversely related to the percentages assigned to level 4 (β = -0.002, P=.008) and level 5 (β = -0.001, P=.017). We found that triage level assignments were related to age, experience, shift, and total number of patients triaged by a nurse.
Quantitative Rapid Assessment of Leukoaraiosis in CT : Comparison to Gold Standard MRI.
Hanning, Uta; Sporns, Peter Bernhard; Schmidt, Rene; Niederstadt, Thomas; Minnerup, Jens; Bier, Georg; Knecht, Stefan; Kemmling, André
2017-10-20
The severity of white matter lesions (WML) is a risk factor of hemorrhage and predictor of clinical outcome after ischemic stroke; however, in contrast to magnetic resonance imaging (MRI) reliable quantification for this surrogate marker is limited for computed tomography (CT), the leading stroke imaging technique. We aimed to present and evaluate a CT-based automated rater-independent method for quantification of microangiopathic white matter changes. Patients with suspected minor stroke (National Institutes of Health Stroke scale, NIHSS < 4) were screened for the analysis of non-contrast computerized tomography (NCCT) at admission and compared to follow-up MRI. The MRI-based WML volume and visual Fazekas scores were assessed as the gold standard reference. We employed a recently published probabilistic brain segmentation algorithm for CT images to determine the tissue-specific density of WM space. All voxel-wise densities were quantified in WM space and weighted according to partial probabilistic WM content. The resulting mean weighted density of WM space in NCCT, the surrogate of WML, was correlated with reference to MRI-based WML parameters. The process of CT-based tissue-specific segmentation was reliable in 79 cases with varying severity of microangiopathy. Voxel-wise weighted density within WM spaces showed a noticeable correlation (r = -0.65) with MRI-based WML volume. Particularly in patients with moderate or severe lesion load according to the visual Fazekas score the algorithm provided reliable prediction of MRI-based WML volume. Automated observer-independent quantification of voxel-wise WM density in CT significantly correlates with microangiopathic WM disease in gold standard MRI. This rapid surrogate of white matter lesion load in CT may support objective WML assessment and therapeutic decision-making during acute stroke triage.
Gyedu, Adam; Agbedinu, Kwabena; Dalwai, Mohammed; Osei-Ampofo, Maxwell; Nakua, Emmanuel Kweku; Oteng, Rockefeller; Stewart, Barclay
2016-01-01
Introduction The incidence of emergency conditions is increasing worldwide, particularly in low- and middle-income countries (LMICs). However, triage and emergency care training has not been prioritized in LMICs. We aimed to assess the reliability and validity of the South African Triage Scale (SATS) when used by providers not specifically trained in SATS, as well as to compare triage capabilities between senior medical students and senior house officers to examine the effectiveness of our curriculum for house officer training with regards to triage. Methods Sixty each of senior medical students and senior house officers who had not undergone specific triage or SATS training were asked to triage 25 previously validated emergency vignettes using the SATS. Estimates of reliability and validity were calculated. Additionally, over- and under-triage, as well as triage performance between the medical students and house officers was assessed against a reference standard. Results Fifty-nine senior medical students (98% response rate) and 43 senior house officers (72% response rate) completed the survey (84% response rate overall). A total of 2,550 triage assignments were included in the analysis (59 medical student and 43 house officer triage assignments for 25 vignettes each; 1,475 and 1,075 triage assignments, respectively). Inter-rater reliability was moderate (quadratically weighted κ 0.59 and 0.60 for medical students and house officers, respectively). Triage using SATS performed by these groups had low sensitivity (medical students: 54%, 95% CI 49–59; house officers: 55%, 95% CI 48–60) and moderate specificity (medical students: 84%, 95% CI 82 - 89; house officers: 84%, 95% CI 82 - 97). Both groups under-triaged most ‘emergency’ level vignette patients (i.e. SATS Red; 80 and 82% for medical students and house officers, respectively). There was no difference between the groups for any metric. Conclusion Although the SATS has proven utility in a number of different settings in LMICs, its success relies on its use by trained providers. Given the large and growing burden of emergency conditions, training current and future emergency care providers in triage is imperative. PMID:28154649
Gyedu, Adam; Agbedinu, Kwabena; Dalwai, Mohammed; Osei-Ampofo, Maxwell; Nakua, Emmanuel Kweku; Oteng, Rockefeller; Stewart, Barclay
2016-01-01
The incidence of emergency conditions is increasing worldwide, particularly in low- and middle-income countries (LMICs). However, triage and emergency care training has not been prioritized in LMICs. We aimed to assess the reliability and validity of the South African Triage Scale (SATS) when used by providers not specifically trained in SATS, as well as to compare triage capabilities between senior medical students and senior house officers to examine the effectiveness of our curriculum for house officer training with regards to triage. Sixty each of senior medical students and senior house officers who had not undergone specific triage or SATS training were asked to triage 25 previously validated emergency vignettes using the SATS. Estimates of reliability and validity were calculated. Additionally, over- and under-triage, as well as triage performance between the medical students and house officers was assessed against a reference standard. Fifty-nine senior medical students (98% response rate) and 43 senior house officers (72% response rate) completed the survey (84% response rate overall). A total of 2,550 triage assignments were included in the analysis (59 medical student and 43 house officer triage assignments for 25 vignettes each; 1,475 and 1,075 triage assignments, respectively). Inter-rater reliability was moderate (quadratically weighted κ 0.59 and 0.60 for medical students and house officers, respectively). Triage using SATS performed by these groups had low sensitivity (medical students: 54%, 95% CI 49-59; house officers: 55%, 95% CI 48-60) and moderate specificity (medical students: 84%, 95% CI 82 - 89; house officers: 84%, 95% CI 82 - 97). Both groups under-triaged most 'emergency' level vignette patients (i.e. SATS Red; 80 and 82% for medical students and house officers, respectively). There was no difference between the groups for any metric. Although the SATS has proven utility in a number of different settings in LMICs, its success relies on its use by trained providers. Given the large and growing burden of emergency conditions, training current and future emergency care providers in triage is imperative.
Effects of anesthetic protocol on normal canine brain uptake of 18F-FDG assessed by PET/CT.
Lee, Min Su; Ko, Jeff; Lee, Ah Ra; Lee, In Hye; Jung, Mi Ae; Austin, Brenda; Chung, Hyunwoo; Nahm, Sangsoep; Eom, Kidong
2010-01-01
The purpose of this study was to assess the effects of four anesthetic protocols on normal canine brain uptake of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) using positron emission tomography/computed tomography (PET/CT). Five clinically normal beagle dogs were anesthetized with (1) propofol/isoflurane, (2) medetomidine/pentobarbital, (3) xylazine/ketamine, and (4) medetomidine/tiletamine-zolazepam in a randomized cross-over design. The standard uptake value (SUV) of FDG was obtained in the frontal, parietal, temporal and occipital lobes, cerebellum, brainstem and whole brain, and compared within and between anesthetic protocols using the Friedman test with significance set at P < 0.05. Significant differences in SUVs were observed in various part of the brain associated with each anesthetic protocol. The SUV for the frontal and occipital lobes was significantly higher than in the brainstem in all dogs. Dogs receiving medetomidine/tiletamine-zolazepam also had significantly higher whole brain SUVs than the propofol/isoflurane group. We concluded that each anesthetic protocol exerted a different regional brain glucose uptake pattern. As a result, when comparing brain glucose uptake using PET/CT, one should consider the effects of anesthetic protocols on different regions of the glucose uptake in the dog's brain.
Relationships of pediatric anthropometrics for CT protocol selection.
Phillips, Grace S; Stanescu, Arta-Luana; Alessio, Adam M
2014-07-01
Determining the optimal CT technique to minimize patient radiation exposure while maintaining diagnostic utility requires patient-specific protocols that are based on patient characteristics. This work develops relationships between different anthropometrics and CT image noise to determine appropriate protocol classification schemes. We measured the image noise in 387 CT examinations of pediatric patients (222 boys, 165 girls) of the chest, abdomen, and pelvis and generated mathematic relationships between image noise and patient lateral and anteroposterior dimensions, age, and weight. At the chest level, lateral distance (ld) across the body is strongly correlated with weight (ld = 0.23 × weight + 16.77; R(2) = 0.93) and is less well correlated with age (ld = 1.10 × age + 17.13; R(2) = 0.84). Similar trends were found for anteroposterior dimensions and at the abdomen level. Across all studies, when acquisition-specific parameters are factored out of the noise, the log of image noise was highly correlated with lateral distance (R(2) = 0.72) and weight (R(2) = 0.72) and was less correlated with age (R(2) = 0.62). Following first-order relationships of image noise and scanner technique, plots were formed to show techniques that could achieve matched noise across the pediatric population. Patient lateral distance and weight are essentially equally effective metrics to base maximum technique settings for pediatric patient-specific protocols. These metrics can also be used to help categorize appropriate reference levels for CT technique and size-specific dose estimates across the pediatric population.
An evaluation of in-plane shields during thoracic CT.
Foley, S J; McEntee, M F; Rainford, L A
2013-08-01
The object of this study was to compare organ dose and image quality effects of using bismuth and barium vinyl in-plane shields with standard and low tube current thoracic CT protocols. A RANDO phantom was scanned using a 64-slice CT scanner and three different thoracic protocols. Thermoluminescent dosemeters were positioned in six locations to record surface and absorbed breast and lung doses. Image quality was assessed quantitatively using region of interest measurements. Scanning was repeated using bismuth and barium vinyl in-plane shields to cover the breasts and the results were compared with standard and reduced dose protocols. Dose reductions were most evident in the breast, skin and anterior lung when shielding was used, with mean reductions of 34, 33 and 10 % for bismuth and 23, 18 and 11 % for barium, respectively. Bismuth was associated with significant increases in both noise and CT attenuation values for all the three protocols, especially anteriorly and centrally. Barium shielding had a reduced impact on image quality. Reducing the overall tube current reduced doses in all the locations by 20-27 % with similar increases in noise as shielding, without impacting on attenuation values. Reducing the overall tube current best optimises dose with minimal image quality impact. In-plane shields increase noise and attenuation values, while reducing anterior organ doses primarily. Shielding remains a useful optimisation tool in CT and barium is an effective alternative to bismuth especially when image quality is of concern.
CT imaging of blunt traumatic bowel and mesenteric injuries.
LeBedis, Christina A; Anderson, Stephan W; Soto, Jorge A
2012-01-01
Delayed diagnosis of a bowel or mesenteric injury resulting in hollow viscus perforation leads to significant morbidity and mortality from hemorrhage, peritonitis, or abdominal sepsis. The timely diagnosis of bowel and mesenteric injuries requiring operative repair depends almost exclusively on their early detection by the radiologist on computed tomography examination, because the clinical signs and symptoms of these injuries are not specific and usually develop late. Therefore, the radiologist must be familiar with the often-subtle imaging findings of bowel and mesenteric injury that will allow for appropriate triage of a patient who has sustained blunt trauma to the abdomen or pelvis. 2012 Elsevier Inc. All rights reserved.
SU-E-P-49: Evaluation of Image Quality and Radiation Dose of Various Unenhanced Head CT Protocols
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, L; Khan, M; Alapati, K
2015-06-15
Purpose: To evaluate the diagnostic value of various unenhanced head CT protocols and predicate acceptable radiation dose level for head CT exam. Methods: Our retrospective analysis included 3 groups, 20 patients per group, who underwent clinical routine unenhanced adult head CT examination. All exams were performed axially with 120 kVp. Three protocols, 380 mAs without iterative reconstruction and automAs, 340 mAs with iterative reconstruction without automAs, 340 mAs with iterative reconstruction and automAs, were applied on each group patients respectively. The images were reconstructed with H30, J30 for brain window and H60, J70 for bone window. Images acquired with threemore » protocols were randomized and blindly reviewed by three radiologists. A 5 point scale was used to rate each exam The percentage of exam score above 3 and average scores of each protocol were calculated for each reviewer and tissue types. Results: For protocols without automAs, the average scores of bone window with iterative reconstruction were higher than those without iterative reconstruction for each reviewer although the radiation dose was 10 percentage lower. 100 percentage exams were scored 3 or higher and the average scores were above 4 for both brain and bone reconstructions. The CTDIvols are 64.4 and 57.8 mGy of 380 and 340 mAs, respectively. With automAs, the radiation dose varied with head size, resulting in 47.5 mGy average CTDIvol between 39.5 and 56.5 mGy. 93 and 98 percentage exams were scored great than 3 for brain and bone windows, respectively. The diagnostic confidence level and image quality of exams with AutomAs were less than those without AutomAs for each reviewer. Conclusion: According to these results, the mAs was reduced to 300 with automAs OFF for head CT exam. The radiation dose was 20 percentage lower than the original protocol and the CTDIvol was reduced to 51.2 mGy.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Y; Zhang, J; Hu, Q
2014-06-01
Purpose: To investigate the possibility of applying optimized scanning protocols for pediatric CT simulation by quantifying the dosimetric inaccuracy introduced by using a fixed HU to density conversion. Methods: The images of a CIRS electron density reference phantom (Model 062) were acquired by a Siemens CT simulator (Sensation Open) using the following settings of tube voltage and beam current: 120 kV/190mA (the reference protocol used to calibrate CT for our treatment planning system (TPS)); Fixed 190mA combined with all available kV: 80, 100, and 140; fixed 120 kV and various current from 37 to 444 mA (scanner extremes) with intervalmore » of 30 mA. To avoid the HU uncertainty of point sampling in the various inserts of known electron densities, the mean CT numbers of the central cylindrical volume were calculated using DICOMan software. The doses per 100 MU to the reference point (SAD=100cm, Depth=10cm, Field=10X10cm, 6MV photon beam) in a virtual cubic phantom (30X30X30cm) were calculated using Eclipse TPS (calculation model: AcurosXB-11031) by assigning the CT numbers to HU of typical materials acquired by various protocols. Results: For the inserts of densities less than muscle, CT number fluctuations of all protocols were within the tolerance of 10 HU as accepted by AAPM-TG66. For more condensed materials, fixed kV yielded stable HU with any mA combination where largest disparities were found in 1750mg/cc insert: HU{sub reference}=1801(106.6cGy), HU{sub minimum}=1799 (106.6cGy, error{sub dose}=0.00%), HU{sub maximum}=1815 (106.8cGy, error{sub dose}=0.19%). Yet greater disagreements were observed with increasing density when kV was modified: HU{sub minimum}=1646 (104.5cGy, error{sub dose}=- 1.97%), HU{sub maximum}=2487 (116.4cGy, error{sub dose}=9.19%) in 1750mg/cc insert. Conclusion: Without affecting treatment dose calculation, personalized mA optimization of CT simulator can be conducted by fixing kV for a better cost-effectiveness of imaging dose and quality especially for children. Unless recalibrated, kV should be constant for all anatomical sites if diagnostic CT scanner is used as a simulator. This work was partially supported by Capital Medical Development Scientific Research Fund of China.« less
Hinson, Jeremiah S; Martinez, Diego A; Schmitz, Paulo S K; Toerper, Matthew; Radu, Danieli; Scheulen, James; Stewart de Ramirez, Sarah A; Levin, Scott
2018-01-15
Emergency department (ED) triage is performed to prioritize care for patients with critical and time-sensitive illness. Triage errors create opportunity for increased morbidity and mortality. Here, we sought to measure the frequency of under- and over-triage of patients by nurses using the Emergency Severity Index (ESI) in Brazil and to identify factors independently associated with each. This was a single-center retrospective cohort study. The accuracy of initial ESI score assignment was determined by comparison with a score entered at the close of each ED encounter by treating physicians with full knowledge of actual resource utilization, disposition, and acute outcomes. Chi-square analysis was used to validate this surrogate gold standard, via comparison of associations with disposition and clinical outcomes. Independent predictors of under- and over-triage were identified by multivariate logistic regression. Initial ESI-determined triage score was classified as inaccurate for 16,426 of 96,071 patient encounters. Under-triage was associated with a significantly higher rate of admission and critical outcome, while over-triage was associated with a lower rate of both. A number of factors identifiable at time of presentation including advanced age, bradycardia, tachycardia, hypoxia, hyperthermia, and several specific chief complaints (i.e., neurologic complaints, chest pain, shortness of breath) were identified as independent predictors of under-triage, while other chief complaints (i.e., hypertension and allergic complaints) were independent predictors of over-triage. Despite rigorous and ongoing training of ESI users, a large number of patients in this cohort were under- or over-triaged. Advanced age, vital sign derangements, and specific chief complaints-all subject to limited guidance by the ESI algorithm-were particularly under-appreciated.
Imaging Evaluation of Acute Traumatic Brain Injury
Mutch, Christopher A.; Talbott, Jason F.; Gean, Alisa
2016-01-01
SYNOPSIS Traumatic brain injury (TBI) is a major cause of morbidity and mortality worldwide. Imaging plays an important role in the evaluation, diagnosis, and triage of patients with TBI. Recent studies suggest that it will also help predict patient outcomes. TBI consists of multiple pathoanatomical entities. Here we review the current state of TBI imaging including its indications, benefits and limitations of the modalities, imaging protocols, and imaging findings for each these pathoanatomic entities. We also briefly survey advanced imaging techniques, which include a number of promising areas of TBI research. PMID:27637393
Validation of different pediatric triage systems in the emergency department
Aeimchanbanjong, Kanokwan; Pandee, Uthen
2017-01-01
BACKGROUND: Triage system in children seems to be more challenging compared to adults because of their different response to physiological and psychosocial stressors. This study aimed to determine the best triage system in the pediatric emergency department. METHODS: This was a prospective observational study. This study was divided into two phases. The first phase determined the inter-rater reliability of five triage systems: Manchester Triage System (MTS), Emergency Severity Index (ESI) version 4, Pediatric Canadian Triage and Acuity Scale (CTAS), Australasian Triage Scale (ATS), and Ramathibodi Triage System (RTS) by triage nurses and pediatric residents. In the second phase, to analyze the validity of each triage system, patients were categorized as two groups, i.e., high acuity patients (triage level 1, 2) and low acuity patients (triage level 3, 4, and 5). Then we compared the triage acuity with actual admission. RESULTS: In phase I, RTS illustrated almost perfect inter-rater reliability with kappa of 1.0 (P<0.01). ESI and CTAS illustrated good inter-rater reliability with kappa of 0.8–0.9 (P<0.01). Meanwhile, ATS and MTS illustrated moderate to good inter-rater reliability with kappa of 0.5–0.7 (P<0.01). In phase II, we included 1 041 participants with average age of 4.7±4.2 years, of which 55% were male and 45% were female. In addition 32% of the participants had underlying diseases, and 123 (11.8%) patients were admitted. We found that ESI illustrated the most appropriate predicting ability for admission with sensitivity of 52%, specificity of 81%, and AUC 0.78 (95%CI 0.74–0.81). CONCLUSION: RTS illustrated almost perfect inter-rater reliability. Meanwhile, ESI and CTAS illustrated good inter-rater reliability. Finally, ESI illustrated the appropriate validity for triage system. PMID:28680520
Role of telephone triage in obstetrics.
Manning, Nirvana Afsordeh; Magann, Everett F; Rhoads, Sarah J; Ivey, Tesa L; Williams, Donna J
2012-12-01
The telephone has become an indispensable method of communication in the practice of obstetrics. The telephone is one of the primary methods by which the patient makes her appointments and contacts her health care provider for advice, reassurance, and referrals. Current methods of telephone triage include personal at the physicians' office, telephone answering services, labor and delivery nurses, and a dedicated telephone triage system using algorithms. Limitations of telephone triage include the inability of the provider to see the patient and receive visual clues from the interaction and the challenges of obtaining a complete history over the telephone. In addition, there are potential safety and legal issues with telephone triage. To date, there is insufficient evidence to either validate or refute the use of a dedicated telephone triage system compared with a traditional system using an answering service or nurses on labor and delivery. Obstetricians and gynecologists, family physicians. After completing this CME activity, physicians should be better able to analyze the scope of variation in telephone triage across health care providers and categorize the components that go into a successful triage system, assess the current scope of research in telephone triage in obstetrics, evaluate potential safety and legal issues with telephone triage in obstetrics, and identify issues that should be addressed in any institution that is using or implementing a system of telephone triage in obstetrics.
Triage: an investigation of the process and potential vulnerabilities.
Hitchcock, Maree; Gillespie, Brigid; Crilly, Julia; Chaboyer, Wendy
2014-07-01
To explore and describe the triage process in the Emergency Department to identify problems and potential vulnerabilities that may affect the triage process. Triage is the first step in the patient journey in the Emergency Department and is often the front line in reducing the potential for errors and mistakes. A fieldwork study to provide an in-depth appreciation and understanding of the triage process. Fieldwork included unstructured observer-only observation, field notes, informal and formal interviews that were conducted over the months of June, July and August 2012. Over 170 hours of observation were performed covering day, evening and night shifts, 7 days of the week. Sixty episodes of triage were observed; 31 informal interviews and 14 formal interviews were completed. Thematic analysis was used. Three themes were identified from the analysis of the data and included: 'negotiating patient flow and care delivery through the Emergency Department'; 'interdisciplinary team communicating and collaborating to provide appropriate and safe care to patients'; and 'varying levels of competence of the triage nurse'. In these themes, vulnerabilities and problems described included over and under triage, extended time to triage assessment, triage errors, multiple patients arriving simultaneously, emergency department and hospital overcrowding. Findings suggest that vulnerabilities in the triage process may cause disruptions to patient flow and compromise care, thus potentially impacting nurses' ability to provide safe and effective care. © 2013 John Wiley & Sons Ltd.
Paul, Jijo; Banckwitz, Rosemarie; Krauss, Bernhard; Vogl, Thomas J; Maentele, Werner; Bauer, Ralf W
2012-04-01
To determine effective dose (E) during standard chest CT using an organ dose-based and a dose-length-product-based (DLP) approach for four different scan protocols including high-pitch and dual-energy in a dual-source CT scanner of the second generation. Organ doses were measured with thermo luminescence dosimeters (TLD) in an anthropomorphic male adult phantom. Further, DLP-based dose estimates were performed by using the standard 0.014mSv/mGycm conversion coefficient k. Examinations were performed on a dual-source CT system (Somatom Definition Flash, Siemens). Four scan protocols were investigated: (1) single-source 120kV, (2) single-source 100kV, (3) high-pitch 120kV, and (4) dual-energy with 100/Sn140kV with equivalent CTDIvol and no automated tube current modulation. E was then determined following recommendations of ICRP publication 103 and 60 and specific k values were derived. DLP-based estimates differed by 4.5-16.56% and 5.2-15.8% relatively to ICRP 60 and 103, respectively. The derived k factors calculated from TLD measurements were 0.0148, 0.015, 0.0166, and 0.0148 for protocol 1, 2, 3 and 4, respectively. Effective dose estimations by ICRP 103 and 60 for single-energy and dual-energy protocols show a difference of less than 0.04mSv. Estimates of E based on DLP work equally well for single-energy, high-pitch and dual-energy CT examinations. The tube potential definitely affects effective dose in a substantial way. Effective dose estimations by ICRP 103 and 60 for both single-energy and dual-energy examinations differ not more than 0.04mSv. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, S; Markel, D; Hegyi, G
2016-06-15
Purpose: The reliability of computed tomography (CT) textures is an important element of radiomics analysis. This study investigates the dependency of lung CT textures on different breathing phases and changes in CT image acquisition protocols in a realistic phantom setting. Methods: We investigated 11 CT texture features for radiation-induced lung disease from 3 categories (first-order, grey level co-ocurrence matrix (GLCM), and Law’s filter). A biomechanical swine lung phantom was scanned at two breathing phases (inhale/exhale) and two scanning protocols set for PET/CT and diagnostic CT scanning. Lung volumes acquired from the CT images were divided into 2-dimensional sub-regions with amore » grid spacing of 31 mm. The distribution of the evaluated texture features from these sub-regions were compared between the two scanning protocols and two breathing phases. The significance of each factor on feature values were tested at 95% significance level using analysis of covariance (ANCOVA) model with interaction terms included. Robustness of a feature to a scanning factor was defined as non-significant dependence on the factor. Results: Three GLCM textures (variance, sum entropy, difference entropy) were robust to breathing changes. Two GLCM (variance, sum entropy) and 3 Law’s filter textures (S5L5, E5L5, W5L5) were robust to scanner changes. Moreover, the two GLCM textures (variance, sum entropy) were consistent across all 4 scanning conditions. First-order features, especially Hounsfield unit intensity features, presented the most drastic variation up to 39%. Conclusion: Amongst the studied features, GLCM and Law’s filter texture features were more robust than first-order features. However, the majority of the features were modified by either breathing phase or scanner changes, suggesting a need for calibration when retrospectively comparing scans obtained at different conditions. Further investigation is necessary to identify the sensitivity of individual image acquisition parameters.« less
Saade, Charbel; Deeb, Ibrahim Alsheikh; Mohamad, Maha; Al-Mohiy, Hussain; El-Merhi, Fadi
2016-01-01
Over the last decade, exponential advances in computed tomography (CT) technology have resulted in improved spatial and temporal resolution. Faster image acquisition enabled renal CT angiography to become a viable and effective noninvasive alternative in diagnosing renal vascular pathologies. However, with these advances, new challenges in contrast media administration have emerged. Poor synchronization between scanner and contrast media administration have reduced the consistency in image quality with poor spatial and contrast resolution. Comprehensive understanding of contrast media dynamics is essential in the design and implementation of contrast administration and image acquisition protocols. This review includes an overview of the parameters affecting renal artery opacification and current protocol strategies to achieve optimal image quality during renal CT angiography with iodinated contrast media, with current safety issues highlighted.
Yuan, XiaoDong; Zhang, Jing; Quan, ChangBin; Tian, Yuan; Li, Hong; Ao, GuoKun
2016-04-01
To determine the feasibility and accuracy of a protocol for calculating whole-organ renal perfusion (renal blood flow [RBF]) and regional perfusion on the basis of biphasic computed tomography (CT), with concurrent dynamic contrast material-enhanced (DCE) CT perfusion serving as the reference standard. This prospective study was approved by the institutional review board, and written informed consent was obtained from all patients. Biphasic CT of the kidneys, including precontrast and arterial phase imaging, was integrated with a first-pass dynamic volume CT protocol and performed and analyzed in 23 patients suspected of having renal artery stenosis. The perfusion value derived from biphasic CT was calculated as CT number enhancement divided by the area under the arterial input function and compared with the DCE CT perfusion data by using the paired t test, correlation analysis, and Bland-Altman plots. Correlation analysis was made between the RBF and the extent of renal artery stenosis. All postprocessing was independently performed by two observers and then averaged as the final result. Mean ± standard deviation biphasic and DCE CT perfusion data for RBF were 425.62 mL/min ± 124.74 and 419.81 mL/min ± 121.13, respectively (P = .53), and for regional perfusion they were 271.15 mL/min per 100 mL ± 82.21 and 266.33 mL/min per 100 mL ± 74.40, respectively (P = .31). Good correlation and agreement were shown between biphasic and DCE CT perfusion for RBF (r = 0.93; ±10% variation from mean perfusion data [P < .001]) and for regional perfusion (r = 0.90; ±13% variation from mean perfusion data [P < .001]). The extent of renal artery stenosis was negatively correlated with RBF with biphasic CT perfusion (r = -0.81, P = .012). Biphasic CT perfusion is clinically feasible and provides perfusion data comparable to DCE CT perfusion data at both global and regional levels in the kidney. Online supplemental material is available for this article.
Paramedic Application of a Triage Sieve: A Paper-Based Exercise.
Cuttance, Glen; Dansie, Kathryn; Rayner, Tim
2017-02-01
Introduction Triage is the systematic prioritization of casualties when there is an imbalance between the needs of these casualties and resource availability. The triage sieve is a recognized process for prioritizing casualties for treatment during mass-casualty incidents (MCIs). While the application of a triage sieve generally is well-accepted, the measurement of its accuracy has been somewhat limited. Obtaining reliable measures for triage sieve accuracy rates is viewed as a necessity for future development in this area. The goal of this study was to investigate how theoretical knowledge acquisition and the practical application of an aide-memoir impacted triage sieve accuracy rates. Two hundred and ninety-two paramedics were allocated randomly to one of four separate sub-groups, a non-intervention control group, and three intervention groups, which involved them receiving either an educational review session and/or an aide-memoir. Participants were asked to triage sieve 20 casualties using a previously trialed questionnaire. The study showed the non-intervention control group had a correct accuracy rate of 47%, a similar proportion of casualties found to be under-triaged (37%), but a significantly lower number of casualties were over-triaged (16%). The provision of either an educational review or aide-memoir significantly increased the correct triage sieve accuracy rate to 77% and 90%, respectively. Participants who received both the educational review and aide-memoir had an overall accuracy rate of 89%. Over-triaged rates were found not to differ significantly across any of the study groups. This study supports the use of an aide-memoir for maximizing MCI triage accuracy rates. A "just-in-time" educational refresher provided comparable benefits, however its practical application to the MCI setting has significant operational limitations. In addition, this study provides some guidance on triage sieve accuracy rate measures that can be applied to define acceptable performance of a triage sieve during a MCI. Cuttance G , Dansie K , Rayner T . Paramedic application of a triage sieve: a paper-based exercise. Prehosp Disaster Med. 2017;32(1):3-13.
Elsholtz, Fabian Henry Jürgen; Kamp, Julia Evi-Katrin; Vahldiek, Janis Lucas; Hamm, Bernd; Niehues, Stefan Markus
2018-06-18
CT-guided periradicular infiltration of the cervical spine is an effective symptomatic treatment in patients with radiculopathy-associated pain syndromes. This study evaluates the robustness and safety of a low-dose protocol on a CT scanner with iterative reconstruction software. A total of 183 patients who underwent periradicular infiltration therapy of the cervical spine were included in this study. 82 interventions were performed on a new CT scanner with a new intervention protocol using an iterative reconstruction algorithm. Spot scanning was implemented for planning and a basic low-dose setup of 80 kVp and 5 mAs was established during intermittent fluoroscopy. The comparison group included 101 prior interventions on a scanner without iterative reconstruction. The dose-length product (DLP), number of acquisitions, pain reduction on a numeric analog scale, and protocol changes to achieve a safe intervention were recorded. The median DLP for the whole intervention was 24.3 mGy*cm in the comparison group and 1.8 mGy*cm in the study group. The median pain reduction was -3 in the study group and -2 in the comparison group. A 5 mAs increase in the tube current-time product was required in 5 patients of the study group. Implementation of a new scanner and intervention protocol resulted in a 92.6 % dose reduction without a compromise in safety and pain relief. The dose needed here is more than 75 % lower than doses used for similar interventions in published studies. An increase of the tube current-time product was needed in only 6 % of interventions. · The presented ultra-low-dose protocol allows for a significant dose reduction without compromising outcome.. · The protocol includes spot scanning for planning purposes and a basic setup of 80 kVp and 5 mAs.. · The iterative reconstruction algorithm is activated during fluoroscopy.. · Elsholtz FH, Kamp JE, Vahldiek JL et al. Periradicular Infiltration of the Cervical Spine: How New CT Scanner Techniques and Protocol Modifications Contribute to the Achievement of Low-Dose Interventions. Fortschr Röntgenstr 2018; DOI: 10.1055/a-0632-3930. © Georg Thieme Verlag KG Stuttgart · New York.
NASA Astrophysics Data System (ADS)
Rupcich, Franco John
The purpose of this study was to quantify the effectiveness of techniques intended to reduce dose to the breast during CT coronary angiography (CTCA) scans with respect to task-based image quality, and to evaluate the effectiveness of optimal energy weighting in improving contrast-to-noise ratio (CNR), and thus the potential for reducing breast dose, during energy-resolved dedicated breast CT. A database quantifying organ dose for several radiosensitive organs irradiated during CTCA, including the breast, was generated using Monte Carlo simulations. This database facilitates estimation of organ-specific dose deposited during CTCA protocols using arbitrary x-ray spectra or tube-current modulation schemes without the need to run Monte Carlo simulations. The database was used to estimate breast dose for simulated CT images acquired for a reference protocol and five protocols intended to reduce breast dose. For each protocol, the performance of two tasks (detection of signals with unknown locations) was compared over a range of breast dose levels using a task-based, signal-detectability metric: the estimator of the area under the exponential free-response relative operating characteristic curve, AFE. For large-diameter/medium-contrast signals, when maintaining equivalent AFE, the 80 kV partial, 80 kV, 120 kV partial, and 120 kV tube-current modulated protocols reduced breast dose by 85%, 81%, 18%, and 6%, respectively, while the shielded protocol increased breast dose by 68%. Results for the small-diameter/high-contrast signal followed similar trends, but with smaller magnitude of the percent changes in dose. The 80 kV protocols demonstrated the greatest reduction to breast dose, however, the subsequent increase in noise may be clinically unacceptable. Tube output for these protocols can be adjusted to achieve more desirable noise levels with lesser dose reduction. The improvement in CNR of optimally projection-based and image-based weighted images relative to photon-counting was investigated for six different energy bin combinations using a bench-top energy-resolving CT system with a cadmium zinc telluride (CZT) detector. The non-ideal spectral response reduced the CNR for the projection-based weighted images, while image-based weighting improved CNR for five out of the six investigated bin combinations, despite this non-ideal response, indicating potential for image-based weighting to reduce breast dose during dedicated breast CT.
[Testicular cancer: a model to optimize the radiological follow-up].
Stebler, V; Pauchard, B; Schmidt, S; Valerio, M; De Bari, B; Berthold, D
2015-05-20
Despite being rare cancers, testicular seminoma and non-seminoma play an important role in oncology: they represent a model on how to optimize radiological follow-up, aiming at a lowest possible radiation exposure and secondary cancer risk. Males diagnosed with testicular cancer undergo frequently prolonged follow-up with CT-scans with potential toxic side effects, in particular secondary cancers. To reduce the risks linked to ionizing radiation, precise follow-up protocols have been developed. The number of recommended CT-scanners has been significantly reduced over the last 10 years. The CT scanners have evolved technically and new acquisition protocols have the potential to reduce the radiation exposure further.
Guggenberger, Roman; Ulbrich, Erika J; Dietrich, Tobias J; Scholz, Rosemarie; Kaelin, Pascal; Köhler, Christoph; Elsässer, Thilo; Le Corroller, Thomas; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav
2017-02-01
To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard. Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated. Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between к = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies. Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT. • FPCT shoulder arthrography is feasible with fluoroscopy and CT in one workflow. • A 5-s FPCT protocol applies a lower radiation dose than MDCT. • A 20-s FPCT protocol is moderately sensitive for cartilage and tendon pathology.
Moore, Craig S; Horsfield, Carl J; Saunderson, John R; Beavis, Andrew W
2015-01-01
Objective: The purpose of this study was to develop size-based radiotherapy kilovoltage cone beam CT (CBCT) protocols for the pelvis. Methods: Image noise was measured in an elliptical phantom of varying size for a range of exposure factors. Based on a previously defined “small pelvis” reference patient and CBCT protocol, appropriate exposure factors for small, medium, large and extra-large patients were derived which approximate the image noise behaviour observed on a Philips CT scanner (Philips Medical Systems, Best, Netherlands) with automatic exposure control (AEC). Selection criteria, based on maximum tube current–time product per rotation selected during the radiotherapy treatment planning scan, were derived based on an audit of patient size. Results: It has been demonstrated that 110 kVp yields acceptable image noise for reduced patient dose in pelvic CBCT scans of small, medium and large patients, when compared with manufacturer's default settings (125 kVp). Conversely, extra-large patients require increased exposure factors to give acceptable images. 57% of patients in the local population now receive much lower radiation doses, whereas 13% require higher doses (but now yield acceptable images). Conclusion: The implementation of size-based exposure protocols has significantly reduced radiation dose to the majority of patients with no negative impact on image quality. Increased doses are required on the largest patients to give adequate image quality. Advances in knowledge: The development of size-based CBCT protocols that use the planning CT scan (with AEC) to determine which protocol is appropriate ensures adequate image quality whilst minimizing patient radiation dose. PMID:26419892
NASA Astrophysics Data System (ADS)
Chen, Liang-Kuang; Wu, Tung-Hsin; Yang, Ching-Ching; Tsai, Chia-Jung; Lee, Jason J. S.
2010-07-01
The aim of this study is to assess radiation dose and the corresponding image quality from suggested CT protocols which depends on different mean heart rate and high heart rate variability by using 256-slice CT. Fifty consecutive patients referred for a cardiac CT examination were included in this study. All coronary computed tomographic angiography (CCTA) examinations were performed on a 256-slice CT scanner with one of five different protocols: retrospective ECG-gating (RGH) with full dose exposure in all R-R intervals (protocol A), RGH of 30-80% pulsing window with tube current modulation (B), RGH of 78±5% pulsing window with tube current modulation (C), prospective ECG-triggering (PGT) of 78% R-R interval with 5% padding window (D) and PGT of 78% R-R interval without padding window (E). Radiation dose parameters and image quality scoring were determined and compared. In this study, no significant differences were found in comparison on image quality of the five different protocols. Protocol A obtained the highest radiation dose comparing with those of protocols B, C, D and E by a factor of 1.6, 2.4, 2.5 and 4.3, respectively ( p<0.001), which were ranged between 2.7 and 11.8 mSv. The PGT could significantly reduce radiation dose delivered to patients, as compared to the RGH. However, the use of PGT has limitations and is only good in assessing cases with lower mean heart rate and stable heart rate variability. With higher mean heart rate and high heart rate variability circumstances, the RGH within 30-80% of R-R interval pulsing window is suggested as a feasible technique for assessing diagnostic performance.
Neely, K W; Eldurkar, J A; Drake, M E
2000-02-01
Emergency medical services (EMS) systems increasingly seek to triage patients to alternative EMS resources. Emergency medical services dispatchers may be asked to perform this triage. New protocols may be necessary. Alternatively, existing protocols may be sufficient for this task. For an existing dispatch protocol to be sufficient, it at least must accurately categorize patient condition and severity based on an external standard. To examine the extent to which nature codes (NCs), or patient condition codes, and severity codes (SCs) currently assigned in one urban 911 center agree with paramedic field findings. The null hypothesis was that there is no routine agreement (75%) between dispatcher-assigned NC or SC and paramedic-assigned NC or SC for the same patient using the same protocol. Emergency medical services dispatch nature and severity code data and matching out-of-hospital data were prospectively gathered over six months. Dispatch data included the NC: caller-identified problem, and the SC: dispatcher-assessed severity. Each NC is modified by one of three SCs (1, 3, or 9): 1 is emergent, 3 is urgent, and 9 is neither. Paramedics verified and/or corrected dispatcher-assigned NCs and SCs using the same dispatch protocol. One thousand forty usable cases fell into 33 unique NC/SC combinations. The designation of SC 1 was assigned 275 times, SC 3 was assigned 736 times, and SC 9 was assigned 24 times. The SC was missing five times. The overall NC agreement was 0.70 (95% CI = 0.697 to 0.703). The overall SC agreement was 0.65 (95% CI = 0.645 to 0.655). The NC agreement exceeded 75% for ten (59%) NC/SC combinations. The SC agreement exceeded 75% for five (29%) NC/SC combinations. There was both NC and SC agreement for four (24%) combinations: urgent breathing problems, urgent diabetic problems, urgent falls, and urgent overdoses. The greatest NC/SC disagreement occurred within emergent and urgent traffic crashes. Paramedics adjusted SC toward lower severity 29% of the time and toward higher severity 5.4% of the time. There was no upward SC adjustment for eight (47%) combinations. Certain dispatcher-assigned NC and SC codes and NC/SC combinations achieved the study threshold. Overall agreement failed to achieve the threshold. The lowest SC level was rarely assigned, preventing a meaningful analysis of all severity levels.
Radiation dose and cancer risk estimates in helical CT for pulmonary tuberculosis infections
NASA Astrophysics Data System (ADS)
Adeleye, Bamise; Chetty, Naven
2017-12-01
The preference for computed tomography (CT) for the clinical assessment of pulmonary tuberculosis (PTB) infections has increased the concern about the potential risk of cancer in exposed patients. In this study, we investigated the correlation between cancer risk and radiation doses from different CT scanners, assuming an equivalent scan protocol. Radiation doses from three 16-slice units were estimated using the CT-Expo dosimetry software version 2.4 and standard CT scan protocol for patients with suspected PTB infections. The lifetime risk of cancer for each scanner was determined using the methodology outlined in the BEIR VII report. Organ doses were significantly different (P < 0.05) between the scanners. The calculated effective dose for scanner H2 is 34% and 37% higher than scanners H3 and H1 respectively. A high and statistically significant correlation was observed between estimated lifetime cancer risk for both male (r2 = 0.943, P < 0.05) and female patients (r2 = 0.989, P < 0.05). The risk variation between the scanners was slightly higher than 2% for all ages but was much smaller for specific ages for male and female patients (0.2% and 0.7%, respectively). These variations provide an indication that the use of a scanner optimizing protocol is imperative.
Bombings specific triage (Bost Tool) tool and its application by healthcare professionals
Sanjay, Jaiswal; Ankur, Verma; Tamorish, Kole
2015-01-01
BACKGROUND: Bombing is a unique incident which produces unique patterns, multiple and occult injuries. Death often is a result of combined blast, ballistic and thermal effect injuries. Various natures of injury, self referrals and arrival by private transportation may lead to “wrong triage” in the emergency department. In India there has been an increase in incidence of bombing in the last 15 years. There is no documented triage tool from the National Disaster Management Authority of India for Bombings. We have tried to develop an ideal bombing specific triage tool which will guide the right patients to the right place at the right time and save more lives. METHODS: There are three methods of studying the triage tool: 1) real disaster; 2) mock drill; 3) table top exercise. In this study, a table top exercise method was selected. There are two groups, each consisting of an emergency physician, a nurse and a paramedic. RESULTS: By using the proportion test, we found that correct triaging was significantly different (P=0.005) in proportion between the two groups: group B (80%) with triage tool performed better in triaging the bomb blast victims than group A (50%) without the bombing specific triage tool performed. CONCLUSION: Development of bombing specific triage tool can reduce under triaging. PMID:26693264
Tuning of automatic exposure control strength in lumbar spine CT.
D'Hondt, A; Cornil, A; Bohy, P; De Maertelaer, V; Gevenois, P A; Tack, D
2014-05-01
To investigate the impact of tuning the automatic exposure control (AEC) strength curve (specific to Care Dose 4D®; Siemens Healthcare, Forchheim, Germany) from "average" to "strong" on image quality, radiation dose and operator dependency during lumbar spine CT examinations. Two hospitals (H1, H2), both using the same scanners, were considered for two time periods (P1 and P2). During P1, the AEC curve was "average" and radiographers had to select one of two protocols according to the body mass index (BMI): "standard" if BMI <30.0 kg m(-2) (120 kV-330 mAs) or "large" if BMI >30.0 kg m(-2) (140 kV-280 mAs). During P2, the AEC curve was changed to "strong", and all acquisitions were obtained with one protocol (120 kV and 270 mAs). Image quality was scored and patients' diameters calculated for both periods. 497 examinations were analysed. There was no significant difference in mean diameters according to hospitals and periods (p > 0.801) and in quality scores between periods (p > 0.172). There was a significant difference between hospitals regarding how often the "large" protocol was assigned [13 (10%)/132 patients in H1 vs 37 (28%)/133 in H2] (p < 0.001). During P1, volume CT dose index (CTDIvol) was higher in H2 (+13%; p = 0.050). In both hospitals, CTDIvol was reduced between periods (-19.2% in H1 and -29.4% in H2; p < 0.001). An operator dependency in protocol selection, unexplained by patient diameters or highlighted by image quality scores, has been observed. Tuning the AEC curve from average to strong enables suppression of the operator dependency in protocol selection and related dose increase, while preserving image quality. CT acquisition protocols based on weight are responsible for biases in protocol selection. Using an appropriate AEC strength curve reduces the number of protocols to one. Operator dependency of protocol selection is thereby eliminated.
NASA Astrophysics Data System (ADS)
Efstathopoulos, E. P.; Kelekis, N. L.; Pantos, I.; Brountzos, E.; Argentos, S.; Grebáč, J.; Ziaka, D.; Katritsis, D. G.; Seimenis, I.
2009-09-01
Computed tomography (CT) coronary angiography has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but high radiation doses have been reported. Prospective ECG-gating using a 'step-and-shoot' axial scanning protocol has been shown to reduce radiation exposure effectively while maintaining diagnostic accuracy. 256-slice scanners with 80 mm detector coverage have been currently introduced into practice, but their impact on radiation exposure has not been adequately studied. The aim of this study was to assess radiation doses associated with CT coronary angiography using a 256-slice CT scanner. Radiation doses were estimated for 25 patients scanned with either prospective or retrospective ECG-gating. Image quality was assessed objectively in terms of mean CT attenuation at selected regions of interest on axial coronary images and subjectively by coronary segment quality scoring. It was found that radiation doses associated with prospective ECG-gating were significantly lower than retrospective ECG-gating (3.2 ± 0.6 mSv versus 13.4 ± 2.7 mSv). Consequently, the radiogenic fatal cancer risk for the patient is much lower with prospective gating (0.0176% versus 0.0737%). No statistically significant differences in image quality were observed between the two scanning protocols for both objective and subjective quality assessments. Therefore, prospective ECG-gating using a 'step-and-shoot' protocol that covers the cardiac anatomy in two axial acquisitions effectively reduces radiation doses in 256-slice CT coronary angiography without compromising image quality.
[Triage duration times: a prospective descriptive study in a level 1° emergency department].
Bambi, Stefano; Ruggeri, Marco
2017-01-01
Triage is the most important tool for clinical risk management in emergency departments (ED). The timing measurement of its phases is fundamental to establish indicators and standards for the optimization of the system. To evaluate the duration time of the phases of triage; to evaluate some variables exerting influence on nurses' performance. prospective descriptive study performed in the ED of Careggi Teaching Hospital in Florence. 14 nurses enrolled by stratified randomization proportion (1/3 of the whole staff ), according to classes of length of service. Triage processes on 150 adult patients were recorded. The mean age of nurses was 39.7 years (SD ± 5.2, range 29-50); the average length of service was 10.3 years (SD ± 4.4, range 3-18); average of triage experience was 8.6 years (SD ± 4.3, range 2-13). The median time from patient's arrival to the end of the triage process was 04': 04" (range 00':47"- 18':08"); the median duration of triage was 01':11" (range 00':07" -11':27"). The length of service and triage experience did not influence the medians of recorded intervals of time, but there were some limitations due to the low sample size. Interruptions were observed 111 (74%) of triage cases. the recorded triage time intervals were similar to those reported in international literature. Actions are needed to reduce the impact of interruptions on triage process' times.
Blank, Lindsay; Coster, Joanne; O'Cathain, Alicia; Knowles, Emma; Tosh, Jonathan; Turner, Janette; Nicholl, Jon
2012-12-01
This paper is a report of the synthesis of evidence on the appropriateness of, and compliance with, telephone triage decisions. Telephone triage plays an important role in managing demand for health care. Important questions are whether triage decisions are appropriate and patients comply with them. CINAHL, Cochrane Clinical Trials Database, Medline, Embase, Web of Science, and Psyc Info were searched between 1980-June 2010. Rapid Evidence Synthesis. The principles of rapid evidence assessment were followed. We identified 54 relevant papers: 26 papers reported appropriateness of triage decision, 26 papers reported compliance with triage decision, and 2 papers reported both. Nurses triaged calls in most of the studies (n=49). Triage decisions rated as appropriate varied between 44-98% and compliance ranged from 56-98%. Variation could not be explained by type of service or method of assessing appropriateness. However, inconsistent definitions of appropriateness may explain some variation. Triage decisions to contact primary care may have lower compliance than decisions to contact emergency services or self care. Telephone triage services can offer appropriate decisions and decisions that callers comply with. However, the association between the appropriateness of a decision and subsequent compliance requires further investigation and further consideration needs to be given to the minority of calls which are inappropriately managed. We suggest that a definition of appropriateness incorporating both accuracy and adequacy of triage decision should be encouraged. © 2012 Blackwell Publishing Ltd.
NASA Astrophysics Data System (ADS)
Gavrielides, Marios A.; DeFilippo, Gino; Berman, Benjamin P.; Li, Qin; Petrick, Nicholas; Schultz, Kurt; Siegelman, Jenifer
2017-03-01
Computed tomography is primarily the modality of choice to assess stability of nonsolid pulmonary nodules (sometimes referred to as ground-glass opacity) for three or more years, with change in size being the primary factor to monitor. Since volume extracted from CT is being examined as a quantitative biomarker of lung nodule size, it is important to examine factors affecting the performance of volumetric CT for this task. More specifically, the effect of reconstruction algorithms and measurement method in the context of low-dose CT protocols has been an under-examined area of research. In this phantom study we assessed volumetric CT with two different measurement methods (model-based and segmentation-based) for nodules with radiodensities of both nonsolid (-800HU and -630HU) and solid (-10HU) nodules, sizes of 5mm and 10mm, and two different shapes (spherical and spiculated). Imaging protocols included CTDIvol typical of screening (1.7mGy) and sub-screening (0.6mGy) scans and different types of reconstruction algorithms across three scanners. Results showed that radio-density was the factor contributing most to overall error based on ANOVA. The choice of reconstruction algorithm or measurement method did not affect substantially the accuracy of measurements; however, measurement method affected repeatability with repeatability coefficients ranging from around 3-5% for the model-based estimator to around 20-30% across reconstruction algorithms for the segmentation-based method. The findings of the study can be valuable toward developing standardized protocols and performance claims for nonsolid nodules.
Sands, Natisha; Elsom, Stephen; Keppich-Arnold, Sandra; Henderson, Kathryn; King, Peter; Bourke-Finn, Karen; Brunning, Debra
2016-02-01
Telephone-based mental health triage services are frontline health-care providers that operate 24/7 to facilitate access to psychiatric assessment and intervention for people requiring assistance with a mental health problem. The mental health triage clinical role is complex, and the populations triage serves are typically high risk; yet to date, no evidence-based methods have been available to assess clinician competence to practice telephone-based mental health triage. The present study reports the findings of a study that investigated the validity and usability of the Mental Health Triage Competency Assessment Tool, an evidence-based, interactive computer programme designed to assist clinicians in developing and assessing competence to practice telephone-based mental health triage. © 2015 Australian College of Mental Health Nurses Inc.
Decreasing triage time: effects of implementing a step-wise ESI algorithm in an EHR.
Villa, Stephen; Weber, Ellen J; Polevoi, Steven; Fee, Christopher; Maruoka, Andrew; Quon, Tina
2018-06-01
To determine if adapting a widely-used triage scale into a computerized algorithm in an electronic health record (EHR) shortens emergency department (ED) triage time. Before-and-after quasi-experimental study. Urban, tertiary care hospital ED. Consecutive adult patient visits between July 2011 and June 2013. A step-wise algorithm, based on the Emergency Severity Index (ESI-5) was programmed into the triage module of a commercial EHR. Duration of triage (triage interval) for all patients and change in percentage of high acuity patients (ESI 1 and 2) completing triage within 15 min, 12 months before-and-after implementation of the algorithm. Multivariable analysis adjusted for confounders; interrupted time series demonstrated effects over time. Secondary outcomes examined quality metrics and patient flow. About 32 546 patient visits before and 33 032 after the intervention were included. Post-intervention patients were slightly older, census was higher and admission rate slightly increased. Median triage interval was 5.92 min (interquartile ranges, IQR 4.2-8.73) before and 2.8 min (IQR 1.88-4.23) after the intervention (P < 0.001). Adjusted mean triage interval decreased 3.4 min (95% CI: -3.6, -3.2). The proportion of high acuity patients completing triage within 15 min increased from 63.9% (95% CI 62.5, 65.2%) to 75.0% (95% CI 73.8, 76.1). Monthly time series demonstrated immediate and sustained improvement following the intervention. Return visits within 72 h and door-to-balloon time were unchanged. Total length of stay was similar. The computerized triage scale improved speed of triage, allowing more high acuity patients to be seen within recommended timeframes, without notable impact on quality.
Twomey, Michèle; Wallis, Lee A; Myers, Jonathan E
2014-07-01
To evaluate the construct of triage acuity as measured by the South African Triage Scale (SATS) against a set of reference vignettes. A modified Delphi method was used to develop a set of reference vignettes. Delphi participants completed a 2-round consensus-building process, and independently assigned triage acuity ratings to 100 written vignettes unaware of the ratings given by others. Triage acuity ratings were summarised for all vignettes, and only those that reached 80% consensus during round 2 were included in the reference set. Triage ratings for the reference vignettes given by two independent experts using the SATS were compared with the ratings given by the international Delphi panel. Measures of sensitivity, specificity, associated percentages for over-triage/under-triage were used to evaluate the construct of triage acuity (as measured by the SATS) by examining the association between the ratings by the two experts and the international panel. On completion of the Delphi process, 42 of the 100 vignettes reached 80% consensus on their acuity rating and made up the reference set. On average, over all acuity levels, sensitivity was 74% (CI 64% to 82%), specificity 92% (CI 87% to 94%), under-triage occurred 14% (CI 8% to 23%) and over-triage 12% (CI 8% to 23%) of the time. The results of this study provide an alternative to evaluating triage scales against the construct of acuity as measured with the SATS. This method of using 80% consensus vignettes may, however, systematically bias the validity estimate towards better performance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Qin, Ziling; Armijo-Olivo, Susan; Woodhouse, Linda J; Gross, Douglas P
2016-03-01
To evaluate the concurrent validity of a clinical decision support tool (Work Assessment Triage Tool (WATT)) developed to select rehabilitation treatments for injured workers with musculoskeletal conditions. Methodological study with cross-sectional and prospective components. Data were obtained from the Workers' Compensation Board of Alberta rehabilitation facility in Edmonton, Canada. A total of 432 workers' compensation claimants evaluated between November 2011 and June 2012. Percentage agreement between the Work Assessment Triage Tool and clinician recommendations was used to determine concurrent validity. In claimants returning to work, frequencies of matching were calculated and compared between clinician and Work Assessment Triage Tool recommendations and the actual programs undertaken by claimants. The frequency of each intervention recommended by clinicians, Work Assessment Triage Tool, and case managers were also calculated and compared. Percentage agreement between clinician and Work Assessment Triage Tool recommendations was poor (19%) to moderate (46%) and Kappa = 0.37 (95% CI -0.02, 0.76). The Work Assessment Triage Tool did not improve upon clinician recommendations as only 14 out of 31 claimants returning to work had programs that contradicted clinician recommendations, but were consistent with Work Assessment Triage Tool recommendations. Clinicians and case managers were inclined to recommend functional restoration, physical therapy, or no rehabilitation while the Work Assessment Triage Tool recommended additional evidence-based interventions, such as workplace-based interventions. Our findings do not provide evidence of concurrent validity for the Work Assessment Triage Tool compared with clinician recommendations. Based on these results, we cannot recommend further implementation of the Work Assessment Triage Tool. However, the Work Assessment Triage Tool appeared more likely than clinicians to recommend interventions supported by evidence; thus warranting further research. © The Author(s) 2015.
Nishi, Fernanda A; Polak, Catarina; Cruz, Diná de Almeida Lopes Monteiro da
2018-05-01
The purpose of the Manchester Triage System is to clinically prioritize each patient seeking care in an emergency department. Patients with suspected acute myocardial infarction who have typical symptoms including chest pain should be classified in the highest priority groups, requiring immediate medical assistance or care within 10 min. As such, the Manchester Triage System should present adequate sensitivity and specificity. This study estimated the sensitivity and specificity of the Manchester Triage System in the triage of patients with chest pain related to the diagnosis of acute myocardial infarction, and the associations between the performance of the Manchester Triage System and selected variables. This was an observational, analytical, cross-sectional, retrospective study. The sensitivity and specificity of the Manchester Triage System were estimated by verifying the triage classification received by these patients and their established medical diagnoses. The sample was composed of 10,087 triage episodes, in which 139 (1.38%) patients had a diagnosis of acute myocardial infarction. In 49 episodes, confirmation of medical diagnosis was not possible. The estimated sensitivity of the Manchester Triage System was 44.60% (36.18-53.27%) and the estimated specificity was 91.30% (90.73-91.85%). Of the 10,038 episodes in which the diagnosis of acute myocardial infarction was confirmed or excluded, 938 patients (9.34%) received an incorrect classification - undertriage or overtriage. This study showed that the specificity of the Manchester Triage System was very good. However, the low sensitivity based on the Manchester Triage System indicated that patients in high priority categories were undertriaged, leading to longer wait times and associated increased risks of adverse events.
Dehghani Soufi, Mahsa; Samad-Soltani, Taha; Shams Vahdati, Samad; Rezaei-Hachesu, Peyman
2018-06-01
Fast and accurate patient triage for the response process is a critical first step in emergency situations. This process is often performed using a paper-based mode, which intensifies workload and difficulty, wastes time, and is at risk of human errors. This study aims to design and evaluate a decision support system (DSS) to determine the triage level. A combination of the Rule-Based Reasoning (RBR) and Fuzzy Logic Classifier (FLC) approaches were used to predict the triage level of patients according to the triage specialist's opinions and Emergency Severity Index (ESI) guidelines. RBR was applied for modeling the first to fourth decision points of the ESI algorithm. The data relating to vital signs were used as input variables and modeled using fuzzy logic. Narrative knowledge was converted to If-Then rules using XML. The extracted rules were then used to create the rule-based engine and predict the triage levels. Fourteen RBR and 27 fuzzy rules were extracted and used in the rule-based engine. The performance of the system was evaluated using three methods with real triage data. The accuracy of the clinical decision support systems (CDSSs; in the test data) was 99.44%. The evaluation of the error rate revealed that, when using the traditional method, 13.4% of the patients were miss-triaged, which is statically significant. The completeness of the documentation also improved from 76.72% to 98.5%. Designed system was effective in determining the triage level of patients and it proved helpful for nurses as they made decisions, generated nursing diagnoses based on triage guidelines. The hybrid approach can reduce triage misdiagnosis in a highly accurate manner and improve the triage outcomes. Copyright © 2018 Elsevier B.V. All rights reserved.
Trattner, Sigal; Halliburton, Sandra; Thompson, Carla M; Xu, Yanping; Chelliah, Anjali; Jambawalikar, Sachin R; Peng, Boyu; Peters, M Robert; Jacobs, Jill E; Ghesani, Munir; Jang, James J; Al-Khalidi, Hussein; Einstein, Andrew J
2018-01-01
This study sought to determine updated conversion factors (k-factors) that would enable accurate estimation of radiation effective dose (ED) for coronary computed tomography angiography (CTA) and calcium scoring performed on 12 contemporary scanner models and current clinical cardiac protocols and to compare these methods to the standard chest k-factor of 0.014 mSv·mGy -1 cm -1 . Accurate estimation of ED from cardiac CT scans is essential to meaningfully compare the benefits and risks of different cardiac imaging strategies and optimize test and protocol selection. Presently, ED from cardiac CT is generally estimated by multiplying a scanner-reported parameter, the dose-length product, by a k-factor which was determined for noncardiac chest CT, using single-slice scanners and a superseded definition of ED. Metal-oxide-semiconductor field-effect transistor radiation detectors were positioned in organs of anthropomorphic phantoms, which were scanned using all cardiac protocols, 120 clinical protocols in total, on 12 CT scanners representing the spectrum of scanners from 5 manufacturers (GE, Hitachi, Philips, Siemens, Toshiba). Organ doses were determined for each protocol, and ED was calculated as defined in International Commission on Radiological Protection Publication 103. Effective doses and scanner-reported dose-length products were used to determine k-factors for each scanner model and protocol. k-Factors averaged 0.026 mSv·mGy -1 cm -1 (95% confidence interval: 0.0258 to 0.0266) and ranged between 0.020 and 0.035 mSv·mGy -1 cm -1 . The standard chest k-factor underestimates ED by an average of 46%, ranging from 30% to 60%, depending on scanner, mode, and tube potential. Factors were higher for prospective axial versus retrospective helical scan modes, calcium scoring versus coronary CTA, and higher (100 to 120 kV) versus lower (80 kV) tube potential and varied among scanner models (range of average k-factors: 0.0229 to 0.0277 mSv·mGy -1 cm -1 ). Cardiac k-factors for all scanners and protocols are considerably higher than the k-factor currently used to estimate ED of cardiac CT studies, suggesting that radiation doses from cardiac CT have been significantly and systematically underestimated. Using cardiac-specific factors can more accurately inform the benefit-risk calculus of cardiac-imaging strategies. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Optimization of dose and image quality in adult and pediatric computed tomography scans
NASA Astrophysics Data System (ADS)
Chang, Kwo-Ping; Hsu, Tzu-Kun; Lin, Wei-Ting; Hsu, Wen-Lin
2017-11-01
Exploration to maximize CT image and reduce radiation dose was conducted while controlling for multiple factors. The kVp, mAs, and iteration reconstruction (IR), affect the CT image quality and radiation dose absorbed. The optimal protocols (kVp, mAs, IR) are derived by figure of merit (FOM) based on CT image quality (CNR) and CT dose index (CTDIvol). CT image quality metrics such as CT number accuracy, SNR, low contrast materials' CNR and line pair resolution were also analyzed as auxiliary assessments. CT protocols were carried out with an ACR accreditation phantom and a five-year-old pediatric head phantom. The threshold values of the adult CT scan parameters, 100 kVp and 150 mAs, were determined from the CT number test and line pairs in ACR phantom module 1and module 4 respectively. The findings of this study suggest that the optimal scanning parameters for adults be set at 100 kVp and 150-250 mAs. However, for improved low- contrast resolution, 120 kVp and 150-250 mAs are optimal. Optimal settings for pediatric head CT scan were 80 kVp/50 mAs, for maxillary sinus and brain stem, while 80 kVp /300 mAs for temporal bone. SNR is not reliable as the independent image parameter nor the metric for determining optimal CT scan parameters. The iteration reconstruction (IR) approach is strongly recommended for both adult and pediatric CT scanning as it markedly improves image quality without affecting radiation dose.
Effective and organ doses from common CT examinations in one general hospital in Tehran, Iran
NASA Astrophysics Data System (ADS)
Khoramian, Daryoush; Hashemi, Bijan
2017-09-01
Purpose: It is well known that the main portion of artificial sources of ionizing radiation to human results from X-ray imaging techniques. However, reports carried out in various countries have indicated that most of their cumulative doses from artificial sources are due to CT examinations. Hence assessing doses resulted from CT examinations is highly recommended by national and international radiation protection agencies. The aim of this research has been to estimate the effective and organ doses in an average human according to 103 and 60 ICRP tissue weighting factor for six common protocols of Multi-Detector CT (MDCT) machine in a comprehensive training general hospital in Tehran/Iran. Methods: To calculate the patients' effective dose, the CT-Expo2.2 software was used. Organs/tissues and effective doses were determined for about 20 patients (totally 122 patients) for every one of six typical CT protocols of the head, neck, chest, abdomen-pelvis, pelvis and spine exams. In addition, the CT dosimetry index (CTDI) was measured in the standard 16 and 32 cm phantoms by using a calibrated pencil ionization chamber for the six protocols and by taking the average value of CT scan parameters used in the hospital compared with the CTDI values displayed on the console device of the machine. Results: The values of the effective dose based on the ICRP 103 tissue weighting factor were: 0.6, 2.0, 3.2, 4.2, 2.8, and 3.9 mSv and based on the ICRP 60 tissue weighting factor were: 0.9, 1.4, 3, 7.9, 4.8 and 5.1 mSv for the head, neck, chest, abdomen-pelvis, pelvis, spine CT exams respectively. Relative differences between those values were -22, 21, 23, -6, -31 and 16 percent for the head, neck, chest, abdomen-pelvis, pelvis, spine CT exams, respectively. The average value of CTDIv calculated for each protocol was: 27.32 ± 0.9, 18.08 ± 2.0, 7.36 ± 2.6, 8.84 ± 1.7, 9.13 ± 1.5, 10.42 ± 0.8 mGy for the head, neck, chest, abdomen-pelvis and spine CT exams, respectively. Conclusions: The highest organ doses delivered by various CT exams were received by brain (15.5 mSv), thyroid (19.00 mSv), lungs (9.3 mSv) and bladder (9.9 mSv), bladder (10.4 mSv), stomach (10.9 mSv) in the head, neck, chest, and the abdomen-pelvis, pelvis, and spine respectively. Except the neck and spine CT exams showing a higher effective dose compared to that reported in Netherlands, other exams indicated lower values compared to those reported by any other country.
Identifying the core competencies of mental health telephone triage.
Sands, Natisha; Elsom, Stephen; Gerdtz, Marie; Henderson, Kathryn; Keppich-Arnold, Sandra; Droste, Nicolas; Prematunga, Roshani K; Wereta, Zewdu W
2013-11-01
The primary aim of this study was to identify the core competencies of mental health telephone triage, including key role tasks, skills, knowledge and responsibilities, in which clinicians are required to be competent to perform safe and effective triage. Recent global trends indicate an increased reliance on telephone-based health services to facilitate access to health care across large populations. The trend towards telephone-based health services has also extended to mental health settings, evidenced by the growing number of mental health telephone triage services providing 24-hour access to specialist mental health assessment and treatment. Mental health telephone triage services are critical to the early identification of mental health problems and the provision of timely, appropriate interventions. In spite of the rapid growth in mental health telephone triage and the important role these services play in the assessment and management of mental illness and related risks, there has been very little research investigating this area of practice. An observational design was employed to address the research aims. Structured observations (using dual wireless headphones) were undertaken on 197 occasions of mental health telephone triage over a three-month period from January to March 2011. The research identified seven core areas of mental health telephone triage practice in which clinicians are required to be competent in to perform effective mental health telephone triage, including opening the call; performing mental status examination; risk assessment; planning and action; termination of call; referral and reporting; and documentation. The findings of this research contribute to the evidence base for mental health telephone triage by articulating the core competencies for practice. The mental health telephone triage competencies identified in this research may be used to define an evidence-based framework for mental health telephone triage practice that aims to improve the quality, consistency and accuracy of telephone-based mental health triage assessment. © 2012 Blackwell Publishing Ltd.
Cost Effectiveness of Field Trauma Triage among Injured Adults Served by Emergency Medical Services
Newgard, Craig D; Yang, Zhuo; Nishijima, Daniel; McConnell, K John; Trent, Stacy; Holmes, James F; Daya, Mohamud; Mann, N Clay; Hsia, Renee Y; Rea, Tom; Wang, N Ewen; Staudenmayer, Kristan; Delgado, M Kit
2016-01-01
Background The American College of Surgeons Committee on Trauma sets national targets for the accuracy of field trauma triage at ≥ 95% sensitivity and ≥ 65% specificity, yet the cost-effectiveness of realizing these goals is unknown. We evaluated the cost-effectiveness of current field trauma triage practices compared to triage strategies consistent with the national targets. Study Design This was a cost-effectiveness analysis using data from 79,937 injured adults transported by 48 emergency medical services (EMS) agencies to 105 trauma and non-trauma hospitals in 6 regions of the Western U.S. from 2006 through 2008. Incremental differences in survival, quality adjusted life years (QALYs), costs, and the incremental cost-effectiveness ratio (ICER; costs per QALY gained) were estimated for each triage strategy over a 1-year and lifetime horizon using a decision analytic Markov model. We considered an ICER threshold of less than $100,000 to be cost-effective. Results For these 6 regions, a high sensitivity triage strategy consistent with national trauma policy (sensitivity 98.6%, specificity 17.1%) would cost $1,317,333 per QALY gained, while current triage practices (sensitivity 87.2%, specificity 64.0%) cost $88,000 per QALY gained compared to a moderate sensitivity strategy (sensitivity 71.2%, specificity 66.5%). Refining EMS transport patterns by triage status improved cost-effectiveness. At the trauma system level, a high-sensitivity triage strategy would save 3.7 additional lives per year at a 1-year cost of $8.78 million, while a moderate sensitivity approach would cost 5.2 additional lives and save $781,616 each year. Conclusions A high-sensitivity approach to field triage consistent with national trauma policy is not cost effective. The most cost effective approach to field triage appears closely tied to triage specificity and adherence to triage-based EMS transport practices. PMID:27178369
Implementing best practice into the emergency department triage process.
Burgess, Luke; Kynoch, Kathryn; Hines, Sonia
2018-05-17
Triage is the process by which emergency departments (EDs) sort patients presenting for medical treatment. The Australasian Triage Scale, validated to measure urgency, answers the question 'This patient should wait for medical assessment and treatment no longer than…' Multiple patients may present within short time frames, and some will have conditions that have outcomes directly related to timeliness of treatment such as stroke, sepsis and myocardial infarction. The safety of patients within the ED is thus directly related to the triage system. This project aimed to compare current triage practice within a metropolitan ED with evidence-based practice guidelines produced by the Australasian College for Emergency Medicine and College of Emergency Nurses Australasia. The clinical audit project was undertaken in an ED in a large metropolitan hospital. Two hundred episodes of triage were audited, 100 in the preimplementation and 100 in the postimplementation phase. Current practice was compared with triage guidelines, barriers to adherence to evidence-based practice identified, and interventions were planned and implemented to address these. The audits of practice focused on five key areas and were assessed against 12 criteria: arrival and triage, documentation, compliance with policy, communication, and triage staff. Overall five criteria showed improvement, with reassessment of patients waiting for treatment, and the time taken for each triage episode achieving the greatest amount of improvement. Four criteria showed no improvement or a decline, and two achieved 100% adherence in both audits. The project sought to undertake a clinical audit of triage practice to evaluate the adherence of practice to evidence-based guidelines. The project has provided strong support for the implementation of a formal nursing role to support the care of waiting room patients, and act as a second triage nurse during periods of high activity. The physical triage environment has been identified as a barrier to optimal adherence to evidence-based practice guidelines. Using effective communication to manage the waiting experience of patients can have positive benefits for both patients and staff.
Sprung, Charles L; Zimmerman, Janice L; Christian, Michael D; Joynt, Gavin M; Hick, John L; Taylor, Bruce; Richards, Guy A; Sandrock, Christian; Cohen, Robert; Adini, Bruria
2010-03-01
To provide recommendations and standard operating procedures for intensive care units and hospital preparedness for an influenza pandemic. Based on a literature review and expert opinion, a Delphi process was used to define the essential topics. Key recommendations include: Hospitals should increase their ICU beds to the maximal extent by expanding ICU capacity and expanding ICUs into other areas. Hospitals should have appropriate beds and monitors for these expansion areas. Establish a management system with control groups at facility, local, regional and/or national levels to exercise authority over resources. Establish a system of communication, coordination and collaboration between the ICU and key interface departments. A plan to access, coordinate and increase labor resources is required with a central inventory of all clinical and non-clinical staff. Delegate duties not within the usual scope of workers' practice. Ensure that adequate essential medical equipment, pharmaceuticals and supplies are available. Protect patients and staff with infection control practices and supporting occupational health policies. Maintain staff confidence with reassurance plans for legal protection and assistance. Have objective, ethical, transparent triage criteria that are applied equitably and publically disclosed. ICU triage of patients should be based on the likelihood for patients to benefit most or a 'first come, first served' basis. Develop protocols for safe performance of high-risk procedures. Train and educate staff. Mortality, although inevitable during a severe influenza outbreak or disaster, can be reduced by adequate preparation.
Suicide bombing attacks: Can external signs predict internal injuries?
Almogy, Gidon; Mintz, Yoav; Zamir, Gideon; Bdolah-Abram, Tali; Elazary, Ram; Dotan, Livnat; Faruga, Mohammed; Rivkind, Avraham I
2006-04-01
To report the distribution and types of injuries in victims of suicide bombing attacks and to identify external signs that would guide triage and initial management. There is a need for information on the degree to which external injuries indicate internal injuries requiring emergency triage. The medical charts and the trauma registry database of all patients who were admitted to the Hadassah Hospital in Jerusalem from August 2001 to August 2004 following a suicide bombing attack were reviewed and analyzed for injury characteristics, number of body areas injured, presence of blast lung injury (BLI), and need for therapeutic laparotomy. Logistic analysis was performed to identify predictors of BLI and intra-abdominal injury. The study population consisted of 154 patients who were injured as a result of 17 attacks. Twenty-eight patients suffered from BLI (18.2%) and 13 patients (8.4%) underwent therapeutic laparotomy. Patients with penetrating head injury and those with > or =4 body areas injured were significantly more likely to suffer from BLI (odds ratio, 3.47 and 4.12, respectively, P < 0.05). Patients with penetrating torso injury and those with > or =4 body areas injured were significantly more likely to suffer from intra-abdominal injury (odds ratio, 22.27 and 4.89, respectively, P < 0.05). Easily recognizable external signs of trauma can be used to predict the occurrence of BLI and intra-abdominal injury. The importance of these signs needs to be incorporated into triage protocols and used to direct victims to the appropriate level of care both from the scene and in the hospital.
2014-01-01
Background Clinical decision support (CDS) has been shown to be effective in improving medical safety and quality but there is little information on how telephone triage benefits from CDS. The aim of our study was to compare triage documentation quality associated with the use of a clinical decision support tool, ExpertRN©. Methods We examined 50 triage documents before and after a CDS tool was used in nursing triage. To control for the effects of CDS training we had an additional control group of triage documents created by nurses who were trained in the CDS tool, but who did not use it in selected notes. The CDS intervention cohort of triage notes was compared to both the pre-CDS notes and the CDS trained (but not using CDS) cohort. Cohorts were compared using the documentation standards of the American Academy of Ambulatory Care Nursing (AAACN). We also compared triage note content (documentation of associated positive and negative features relating to the symptoms, self-care instructions, and warning signs to watch for), and documentation defects pertinent to triage safety. Results Three of five AAACN documentation standards were significantly improved with CDS. There was a mean of 36.7 symptom features documented in triage notes for the CDS group but only 10.7 symptom features in the pre-CDS cohort (p < 0.0001) and 10.2 for the cohort that was CDS-trained but not using CDS (p < 0.0001). The difference between the mean of 10.2 symptom features documented in the pre-CDS and the mean of 10.7 symptom features documented in the CDS-trained but not using was not statistically significant (p = 0.68). Conclusions CDS significantly improves triage note documentation quality. CDS-aided triage notes had significantly more information about symptoms, warning signs and self-care. The changes in triage documentation appeared to be the result of the CDS alone and not due to any CDS training that came with the CDS intervention. Although this study shows that CDS can improve documentation, further study is needed to determine if it results in improved care. PMID:24645674
North, Frederick; Richards, Debra D; Bremseth, Kimberly A; Lee, Mary R; Cox, Debra L; Varkey, Prathibha; Stroebel, Robert J
2014-03-20
Clinical decision support (CDS) has been shown to be effective in improving medical safety and quality but there is little information on how telephone triage benefits from CDS. The aim of our study was to compare triage documentation quality associated with the use of a clinical decision support tool, ExpertRN©. We examined 50 triage documents before and after a CDS tool was used in nursing triage. To control for the effects of CDS training we had an additional control group of triage documents created by nurses who were trained in the CDS tool, but who did not use it in selected notes. The CDS intervention cohort of triage notes was compared to both the pre-CDS notes and the CDS trained (but not using CDS) cohort. Cohorts were compared using the documentation standards of the American Academy of Ambulatory Care Nursing (AAACN). We also compared triage note content (documentation of associated positive and negative features relating to the symptoms, self-care instructions, and warning signs to watch for), and documentation defects pertinent to triage safety. Three of five AAACN documentation standards were significantly improved with CDS. There was a mean of 36.7 symptom features documented in triage notes for the CDS group but only 10.7 symptom features in the pre-CDS cohort (p < 0.0001) and 10.2 for the cohort that was CDS-trained but not using CDS (p < 0.0001). The difference between the mean of 10.2 symptom features documented in the pre-CDS and the mean of 10.7 symptom features documented in the CDS-trained but not using was not statistically significant (p = 0.68). CDS significantly improves triage note documentation quality. CDS-aided triage notes had significantly more information about symptoms, warning signs and self-care. The changes in triage documentation appeared to be the result of the CDS alone and not due to any CDS training that came with the CDS intervention. Although this study shows that CDS can improve documentation, further study is needed to determine if it results in improved care.
Masiello, Italo; Ponzer, Sari; Farrokhnia, Nasim
2018-01-01
Objective To determine the impact on emergency department (ED) throughput times and proportion of patients who leave without being seen by a physician (LWBS) of two triage interventions, where comprehensive nurse-led triage was first replaced by senior physician-led triage and then by interprofessional teamwork. Design Single-centre before-and-after study. Setting Adult ED of a Swedish urban hospital. Participants Patients arriving on weekdays 08:00 to 21:00 during three 1-year periods in the interval May 2012 to November 2015. A total of 185 806 arrivals were included. Interventions Senior physicians replaced triage nurses May 2013 to May 2014. Interprofessional teamwork replaced the triage process on weekdays 08:00 to 21:00 November 2014 to November 2015. Main outcome measures Primary outcomes were the median time to physician (TTP) and the median length of stay (LOS). Secondary outcome was the LWBS rate. Results The crude median LOS was shortest for teamwork, 228 min (95% CI 226.4 to 230.5) compared with 232 min (95% CI 230.8 to 233.9) for nurse-led and 250 min (95% CI 248.5 to 252.6) for physician-led triage. The adjusted LOS for the teamwork period was 16 min shorter than for nurse-led triage and 23 min shorter than for physician-led triage. The median TTP was shortest for physician-led triage, 56 min (95% CI 54.5 to 56.6) compared with 116 min (95% CI 114.4 to 117.5) for nurse-led triage and 74 min (95% CI 72.7 to 74.8) for teamwork. The LWBS rate was 1.9% for nurse-led triage, 1.2% for physician-led triage and 3.2% for teamwork. All outcome measure differences had two-tailed p values<0.01. Conclusions Interprofessional teamwork had the shortest length of stay, a shorter time to physician than nurse-led triage, but a higher LWBS rate. Interprofessional teamwork may be a useful approach to reducing ED throughput times. PMID:29674366
[Triage evaluation making in a pediatric emergency department of a tertiary hospital].
Pascual-Fernández, Ma Cristina; Ignacio-Cerro, Ma Carmen; Jiménez-Carrascosa, Ma Amalia
2014-03-01
Evaluation triage level assignments depending level of the professionals' education and experience in the unit. This was a retrospective and observational study to triages making from January to March 2012 in Pediatric Emergency Department of tertiary hospital in Madrid. The collection data included variables from Pediatric Canadian Triage with five levels, triage tool using in the unit. 6443 triages were evaluated. The most common mistakes was: not to register pain level, 1445 (22.4%); not to register hydration level, 377 (5.9%); principal symptoms inappropriate, 232 (3.6%). Didn't indicate pain level 140 (5.6%) nurses with 12 hour formal training on triage; 492 (14.5%) with training in the unit, and 92 (16.3%) without training in the last year (p < 0.001). Among the nurses working in the unit more than 7 years did not register pain level 472 (12.3%), identified inappropriate principal symptoms 197 (5%) and did not register hydration level 296 (7.7%). The triage education favors better adaptation in the triage assignment. The most common errors are: not to register level pain and hydration when it's needed for the principal symptoms.
Saade, Charbel; Deeb, Ibrahim Alsheikh; Mohamad, Maha; Al-Mohiy, Hussain; El-Merhi, Fadi
2016-01-01
Over the last decade, exponential advances in computed tomography (CT) technology have resulted in improved spatial and temporal resolution. Faster image acquisition enabled renal CT angiography to become a viable and effective noninvasive alternative in diagnosing renal vascular pathologies. However, with these advances, new challenges in contrast media administration have emerged. Poor synchronization between scanner and contrast media administration have reduced the consistency in image quality with poor spatial and contrast resolution. Comprehensive understanding of contrast media dynamics is essential in the design and implementation of contrast administration and image acquisition protocols. This review includes an overview of the parameters affecting renal artery opacification and current protocol strategies to achieve optimal image quality during renal CT angiography with iodinated contrast media, with current safety issues highlighted. PMID:26728701
Chicheportiche, Alexandre; Artoul, Faozi; Schwartz, Arnon; Grozinsky-Glasberg, Simona; Meirovitz, Amichay; Gross, David J; Godefroy, Jeremy
2018-06-19
Peptide receptor radionuclide therapy (PRRT) with [ 177 Lu]-DOTA-TATE is an effective treatment of neuroendocrine tumors (NETs). After each cycle of treatment, patient dosimetry evaluates the radiation dose to the risk organs, kidneys, and bone marrow, the most radiosensitive tissues. Absorbed doses are calculated from the radioactivity in the blood and from single photon emission computed tomography (SPECT) images corrected by computed tomography (CT) acquired after each course of treatment. The aim of this work is to assess whether the dosimetry along all treatment cycles can be calculated using a single CT. We hypothesize that the absorbed doses to the risk organs calculated with a single CT will be accurate enough to correctly manage the patients, i.e., whether or not to continue PRRT. Twenty-four patients diagnosed with metastatic NETs undergoing PRRT with [ 177 Lu]-DOTA-TATE were retrospectively included in this study. We compared radiation doses to the kidneys and bone marrow using two protocols. In the "classical" one, dosimetry is calculated based on a SPECT and a CT after each treatment cycle. In the new protocol, dosimetry is calculated based on a SPECT study after each cycle but with the first acquired CT for all cycles. The decision whether or not to stop PRRT because of unsafe absorbed dose to the risk organs would have been the same had the classical or the new protocol been used. The agreement between the cumulative doses to the kidneys and bone marrow obtained from the two protocols was excellent with Pearson's correlation coefficients r = 0.95 and r = 0.99 (P < 0.0001) and mean relative differences of 5.30 ± 6.20% and 0.48 ± 4.88%, respectively. Dosimetry calculations for a given patient can be done using a single CT registered to serial SPECTs. This new protocol reduces the need for a hybrid camera in the follow-up of patients receiving [ 177 Lu]-DOTA-TATE.
Richards, David A; Meakins, Joan; Tawfik, Jane; Godfrey, Lesley; Dutton, Evelyn; Richardson, Gerald; Russell, Daphne
2002-01-01
Objective To compare the workloads of general practitioners and nurses and costs of patient care for nurse telephone triage and standard management of requests for same day appointments in routine primary care. Design Multiple interrupted time series using sequential introduction of experimental triage system in different sites with repeated measures taken one week in every month for 12 months. Setting Three primary care sites in York. Participants 4685 patients: 1233 in standard management, 3452 in the triage system. All patients requesting same day appointments during study weeks were included in the trial. Main outcome measures Type of consultation (telephone, appointment, or visit), time taken for consultation, presenting complaints, use of services during the month after same day contact, and costs of drugs and same day, follow up, and emergency care. Results The triage system reduced appointments with general practitioner by 29-44%. Compared with standard management, the triage system had a relative risk (95% confidence interval) of 0.85 (0.72 to 1.00) for home visits, 2.41 (2.08 to 2.80) for telephone care, and 3.79 (3.21 to 4.48) for nurse care. Mean overall time in the triage system was 1.70 minutes longer, but mean general practitioner time was reduced by 2.45 minutes. Routine appointments and nursing time increased, as did out of hours and accident and emergency attendance. Costs did not differ significantly between standard management and triage: mean difference £1.48 more per patient for triage (95% confidence interval –0.19 to 3.15). Conclusions Triage reduced the number of same day appointments with general practitioners but resulted in busier routine surgeries, increased nursing time, and a small but significant increase in out of hours and accident and emergency attendance. Consequently, triage does not reduce overall costs per patient for managing same day appointments. What is already known on this topicNurse telephone triage is used to manage the increasing demand for same day appointments in general practiceEvidence that nurse telephone triage is effective is limitedWhat this study addsTriage resulted in 29-44% fewer same day appointments with general practitioners than standard managementNursing and overall time increased in the triage group as 40% of patients were managed by nursesTriage was not less costly than standard management because of increased costs for nursing, follow up, out of hours, and accident and emergency care PMID:12446539
Cicero, Mark X; Auerbach, Marc A; Zigmont, Jason; Riera, Antonio; Ching, Kevin; Baum, Carl R
2012-06-01
Pediatric disaster medicine (PDM) triage is a vital skill set for pediatricians, and is a required component of residency training by the Accreditation Council for Graduate Medical Education (ACGME). Simulation training is an effective tool for preparing providers for high-stakes, low-frequency events. Debriefing is a learner-centered approach that affords reflection on one's performance, and increases the efficacy of simulation training. The purpose of this study was to measure the efficacy of a multiple-victim simulation in facilitating learners' acquisition of pediatric disaster medicine (PDM) skills, including the JumpSTART triage algorithm. It was hypothesized that multiple patient simulations and a structured debriefing would improve triage performance. A 10-victim school-shooting scenario was created. Victims were portrayed by adult volunteers, and by high- and low-fidelity simulation manikins that responded physiologically to airway maneuvers. Learners were pediatrics residents. Expected triage levels were not revealed. After a didactic session, learners completed the first simulation. Learners assigned triage levels to all victims, and recorded responses on a standardized form. A group structured debriefing followed the first simulation. The debriefing allowed learners to review the victims and discuss triage rationale. A new 10-victim trauma disaster scenario was presented one week later, and a third scenario was presented five months later. During the second and third scenarios, learners again assigned triage levels to multiple victims. Wilcoxon sign rank tests were used to compare pre- and post-test scores and performance on pre- and post-debriefing simulations. A total of 53 learners completed the educational intervention. Initial mean triage performance was 6.9/10 patients accurately triaged (range = 5-10, SD = 1.3); one week after the structured debriefing, the mean triage performance improved to 8.0/10 patients (range = 5-10, SD = 1.37, P < .0001); five months later, there was maintenance of triage improvement, with a mean triage score of 7.8/10 patients (SD = 1.33, P < .0001). Over-triage of an uninjured child with special health care needs (CSHCN) (67.8% of learners prior to debriefing, 49.0% one week post-debriefing, 26.2% five months post-debriefing) and under-triage of head-injured, unresponsive patients (41.2% of learners pre-debriefing, 37.5% post-debriefing, 11.0% five months post-debriefing) were the most common errors. Structured debriefings are a key component of PDM simulation education, and resulted in improved triage accuracy; the improvement was maintained five months after the educational intervention. Future curricula should emphasize assessment of CSHCN and head-injured patients.
[PET/CT: protocol aspects and legal controversies].
Gorospe Sarasúa, L; Vicente Bártulos, A; González Gordaliza, C; García Poza, J; Lourido García, D; Jover Díaz, R
2008-01-01
The combination of positron emission tomography (PET) and computed tomography (CT) in a single scanner (PET/CT) allows anatomic and metabolic images to be fused and correlated with a high degree of accuracy; this represents a very important landmark in the history of medicine and especially in the area of diagnostic imaging. Nevertheless, the implementation, startup, and operation of a PET/CT scanner presents particularly interesting challenges, because it involves the integration of two well-established and consolidated techniques (CT and PET, which provide complementary information) that have traditionally been carried out in the context of two different specialties (radiology and nuclear medicine). The rapid diffusion of this new integrated technology raises a series of questions related to the optimal protocols for image acquisition, the supervision of the examinations, image interpretation, and reporting, as well as questions related to the legal competence and responsibility of the specialists involved in a PET/CT study. The objective of this article is to approach these aspects from a constructive perspective and to stimulate the dialog between the specialties of radiology and nuclear medicine, with the aim of maximizing the diagnostic potential of PET/CT and thus of providing better care for patients.
Favazza, Christopher P; Ferrero, Andrea; Yu, Lifeng; Leng, Shuai; McMillan, Kyle L; McCollough, Cynthia H
2017-07-01
The use of iterative reconstruction (IR) algorithms in CT generally decreases image noise and enables dose reduction. However, the amount of dose reduction possible using IR without sacrificing diagnostic performance is difficult to assess with conventional image quality metrics. Through this investigation, achievable dose reduction using a commercially available IR algorithm without loss of low contrast spatial resolution was determined with a channelized Hotelling observer (CHO) model and used to optimize a clinical abdomen/pelvis exam protocol. A phantom containing 21 low contrast disks-three different contrast levels and seven different diameters-was imaged at different dose levels. Images were created with filtered backprojection (FBP) and IR. The CHO was tasked with detecting the low contrast disks. CHO performance indicated dose could be reduced by 22% to 25% without compromising low contrast detectability (as compared to full-dose FBP images) whereas 50% or more dose reduction significantly reduced detection performance. Importantly, default settings for the scanner and protocol investigated reduced dose by upward of 75%. Subsequently, CHO-based protocol changes to the default protocol yielded images of higher quality and doses more consistent with values from a larger, dose-optimized scanner fleet. CHO assessment provided objective data to successfully optimize a clinical CT acquisition protocol.
Luigi Ingrassia, Pier; Ragazzoni, Luca; Carenzo, Luca; Colombo, Davide; Ripoll Gallardo, Alba; Della Corte, Francesco
2015-04-01
This study tested the hypothesis that virtual reality simulation is equivalent to live simulation for testing naive medical students' abilities to perform mass casualty triage using the Simple Triage and Rapid Treatment (START) algorithm in a simulated disaster scenario and to detect the improvement in these skills after a teaching session. Fifty-six students in their last year of medical school were randomized into two groups (A and B). The same scenario, a car accident, was developed identically on the two simulation methodologies: virtual reality and live simulation. On day 1, group A was exposed to the live scenario and group B was exposed to the virtual reality scenario, aiming to triage 10 victims. On day 2, all students attended a 2-h lecture on mass casualty triage, specifically the START triage method. On day 3, groups A and B were crossed over. The groups' abilities to perform mass casualty triage in terms of triage accuracy, intervention correctness, and speed in the scenarios were assessed. Triage and lifesaving treatment scores were assessed equally by virtual reality and live simulation on day 1 and on day 3. Both simulation methodologies detected an improvement in triage accuracy and treatment correctness from day 1 to day 3 (P<0.001). The time to complete each scenario and its decrease from day 1 to day 3 were detected equally in the two groups (P<0.05). Virtual reality simulation proved to be a valuable tool, equivalent to live simulation, to test medical students' abilities to perform mass casualty triage and to detect improvement in such skills.
Drescher, Robert; Gühne, Falk; Freesmeyer, Martin
2017-06-01
To propose a positron emission tomography (PET)/computed tomography (CT) protocol including early-dynamic and late-phase acquisitions to evaluate graft patency and aneurysm diameter, detect endoleaks, and rule out graft or vessel wall inflammation after endovascular aneurysm repair (EVAR) in one examination without intravenous contrast medium. Early-dynamic PET/CT of the endovascular prosthesis is performed for 180 seconds immediately after intravenous injection of F-18-fluorodeoxyglucose. Data are reconstructed in variable time frames (time periods after tracer injection) to visualize the arterial anatomy and are displayed as PET angiography or fused with CT images. Images are evaluated in view of vascular abnormalities, graft configuration, and tracer accumulation in the aneurysm sac. Whole-body PET/CT is performed 90 to 120 minutes after tracer injection. This protocol for early-dynamic PET/CT and PET angiography has the potential to evaluate vascular diseases, including the diagnosis of complications after endovascular procedures.
MDCT imaging of the stomach: advances and applications
Prakash, Anjali; Pradhan, Gaurav; Vidholia, Aditi; Nagpal, Nishant; Saboo, Sachin S; Kuehn, David M; Khandelwal, Ashish
2017-01-01
The stomach may be involved by a myriad of pathologies ranging from benign aetiologies like inflammation to malignant aetiologies like carcinoma or lymphoma. Multidetector CT (MDCT) of the stomach is the first-line imaging for patients with suspected gastric pathologies. Conventionally, CT imaging had the advantage of simultaneous detection of the mural and extramural disease extent, but advances in MDCT have allowed mucosal assessment by virtual endoscopy (VE). Also, better three-dimensional (3D) post-processing techniques have enabled more robust and accurate pre-operative planning in patients undergoing gastrectomy and even predict the response to surgery for patients undergoing laparoscopic sleeve gastrectomy for weight loss. The ability of CT to obtain stomach volume (for bariatric surgery patients) and 3D VE images depends on various patient and protocol factors that are important for a radiologist to understand. We review the appropriate CT imaging protocol in the patients with suspected gastric pathologies and highlight the imaging pearls of various gastric pathologies on CT and VE. PMID:27785936
MDCT imaging of the stomach: advances and applications.
Nagpal, Prashant; Prakash, Anjali; Pradhan, Gaurav; Vidholia, Aditi; Nagpal, Nishant; Saboo, Sachin S; Kuehn, David M; Khandelwal, Ashish
2017-01-01
The stomach may be involved by a myriad of pathologies ranging from benign aetiologies like inflammation to malignant aetiologies like carcinoma or lymphoma. Multidetector CT (MDCT) of the stomach is the first-line imaging for patients with suspected gastric pathologies. Conventionally, CT imaging had the advantage of simultaneous detection of the mural and extramural disease extent, but advances in MDCT have allowed mucosal assessment by virtual endoscopy (VE). Also, better three-dimensional (3D) post-processing techniques have enabled more robust and accurate pre-operative planning in patients undergoing gastrectomy and even predict the response to surgery for patients undergoing laparoscopic sleeve gastrectomy for weight loss. The ability of CT to obtain stomach volume (for bariatric surgery patients) and 3D VE images depends on various patient and protocol factors that are important for a radiologist to understand. We review the appropriate CT imaging protocol in the patients with suspected gastric pathologies and highlight the imaging pearls of various gastric pathologies on CT and VE.
Protocols for Automated Protist Analysis
2011-12-01
Report No: CG-D-14-13 Protocols for Automated Protist Analysis December 2011 Distribution Statement A: Approved for public...release; distribution is unlimited. Protocols for Automated Protist Analysis ii UNCLAS//Public | CG-926 RDC | B. Nelson, et al. | Public...Director United States Coast Guard Research & Development Center 1 Chelsea Street New London, CT 06320 Protocols for Automated Protist Analysis
Sethia, Rishabh; Mahida, Justin B; Subbarayan, Rahul A; Deans, Katherine J; Minneci, Peter C; Elmaraghy, Charles A; Essig, Garth F
2017-05-01
To determine the clinical impact of an initiative to use ultrasound (US) as the primary diagnostic modality for children with superficial face and neck infections versus use of computed tomography (CT). Children with a diagnosis of lymphadenitis, face or neck abscess, or face and neck cellulitis were retrospectively evaluated by the otolaryngology service. Patients were separated into two groups based on implementation of a departmental initiative to use US as the primary diagnostic modality. The pre-implementation cohort consisted of patients treated prior to the initiative (2006-2009) and the current protocol cohort consisted of patients treated after the initiative was started (2010-2013). Demographics, use of US or CT, necessity of surgical intervention, and failure of medical management were compared. Three hundred seventy three children were evaluated; 114 patients were included in the pre-implementation cohort and 259 patients were included in the current protocol cohort for comparison. Patients presenting during the current protocol period were more likely to undergo US (pre-implementation vs. current protocol, p-value) (12% vs. 49%, p < 0.0001) and less likely to undergo CT (66% vs. 41%, p < 0.0001) for their initial evaluation. There were no differences in the percentage of children who underwent prompt surgical drainage, prompt discharge without surgery, or trial inpatient observation. There were also no differences in the rate of treatment failure for patients undergoing prompt surgery or prompt discharge on antibiotics. For those patients who underwent repeat evaluation following trial medical management, US was used more frequently in the current protocol period (4% vs. 20%, p = 0.002) with no difference in CT use, selected treatment strategy, or treatment failure rates. Increased use of US on initial evaluation of children with superficial face and neck infections resulted in decreased CT utilization, without negatively impacting outcome. Decreasing pediatric radiation exposure and potential long-term effects is of primary importance. Copyright © 2017. Published by Elsevier B.V.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Ching-Ching, E-mail: cyang@tccn.edu.tw; Liu, Shu-Hsin; Mok, Greta S. P.
Purpose: This study aimed to tailor the CT imaging protocols for pediatric patients undergoing whole-body PET/CT examinations with appropriate attention to radiation exposure while maintaining adequate image quality for anatomic delineation of PET findings and attenuation correction of PET emission data. Methods: The measurements were made by using three anthropomorphic phantoms representative of 1-, 5-, and 10-year-old children with tube voltages of 80, 100, and 120 kVp, tube currents of 10, 40, 80, and 120 mA, and exposure time of 0.5 s at 1.75:1 pitch. Radiation dose estimates were derived from the dose-length product and were used to calculate riskmore » estimates for radiation-induced cancer. The influence of image noise on image contrast and attenuation map for CT scans were evaluated based on Pearson's correlation coefficient and covariance, respectively. Multiple linear regression methods were used to investigate the effects of patient age, tube voltage, and tube current on radiation-induced cancer risk and image noise for CT scans. Results: The effective dose obtained using three anthropomorphic phantoms and 12 combinations of kVp and mA ranged from 0.09 to 4.08 mSv. Based on our results, CT scans acquired with 80 kVp/60 mA, 80 kVp/80 mA, and 100 kVp/60 mA could be performed on 1-, 5-, and 10-year-old children, respectively, to minimize cancer risk due to CT scans while maintaining the accuracy of attenuation map and CT image contrast. The effective doses of the proposed protocols for 1-, 5- and 10-year-old children were 0.65, 0.86, and 1.065 mSv, respectively. Conclusions: Low-dose pediatric CT protocols were proposed to balance the tradeoff between radiation-induced cancer risk and image quality for patients ranging in age from 1 to 10 years old undergoing whole-body PET/CT examinations.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanders, J; Tian, X; Segars, P
2016-06-15
Purpose: To develop an automated technique for estimating patient-specific regional imparted energy and dose from tube current modulated (TCM) computed tomography (CT) exams across a diverse set of head and body protocols. Methods: A library of 58 adult computational anthropomorphic extended cardiac-torso (XCAT) phantoms were used to model a patient population. A validated Monte Carlo program was used to simulate TCM CT exams on the entire library of phantoms for three head and 10 body protocols. The net imparted energy to the phantoms, normalized by dose length product (DLP), and the net tissue mass in each of the scan regionsmore » were computed. A knowledgebase containing relationships between normalized imparted energy and scanned mass was established. An automated computer algorithm was written to estimate the scanned mass from actual clinical CT exams. The scanned mass estimate, DLP of the exam, and knowledgebase were used to estimate the imparted energy to the patient. The algorithm was tested on 20 chest and 20 abdominopelvic TCM CT exams. Results: The normalized imparted energy increased with increasing kV for all protocols. However, the normalized imparted energy was relatively unaffected by the strength of the TCM. The average imparted energy was 681 ± 376 mJ for abdominopelvic exams and 274 ± 141 mJ for chest exams. Overall, the method was successful in providing patientspecific estimates of imparted energy for 98% of the cases tested. Conclusion: Imparted energy normalized by DLP increased with increasing tube potential. However, the strength of the TCM did not have a significant effect on the net amount of energy deposited to tissue. The automated program can be implemented into the clinical workflow to provide estimates of regional imparted energy and dose across a diverse set of clinical protocols.« less
McAllister, E; Perez, M; Albrink, M H; Olsen, S M; Rosemurgy, A S
1994-09-01
We devised a protocol to prospectively manage stab wounds to the back with the hypothesis that the triple contrast computed tomographic (CT) scan is an effective means of detecting occult injury in these patients. All wounds to the back in hemodynamically stable adults were locally explored. All patients with muscular fascial penetration underwent triple contrast CT scanning utilizing oral, rectal, and IV contrast. Patients did not undergo surgical exploration if their CT scan was interpreted as negative or if the CT scan demonstrated injuries not requiring surgical intervention. Fifty-three patients were entered into the protocol. The time to complete the triple contrast CT scan ranged from 3 to 6 hours at a cost of $1050 for each scan. In 51 patients (96%), the CT scan either had negative findings (n = 31) or showed injuries not requiring exploration (n = 20). These patients did well with nonsurgical management. Two CT scans documented significant injury and led to surgical exploration and therapeutic celiotomies. Although triple contrast CT scanning was able to detect occult injury in patients with stab wounds to the back it did so at considerable cost and the results rarely altered clinical care. Therefore, its routine use in these patients is not recommended.
Young, Victoria Solveig; Eggesbø, Heidi B; Gaarder, Christine; Næss, Pål Aksel; Enden, Tone
2017-07-01
To describe the use of radiology in the emergency department (ED) in a trauma centre during a mass casualty incident, using a minimum acceptable care (MAC) strategy in which CT was restricted to potentially severe head injuries. We retrospectively studied the initial use of imaging on patients triaged to the trauma centre following the twin terrorist attacks in Norway on 22 July 2011. Nine patients from the explosion and 15 from the shooting were included. Fourteen patients had an Injury Severity Score >15. During the first 15 h, 22/24 patients underwent imaging in the ED. All 15 gunshot patients had plain films taken in the ED, compared to three from the explosion. A CT was performed in 18/24 patients; ten of these were completed in the ED and included five non-head CTs, the latter representing deviations from the MAC strategy. No CT referrals were delayed or declined. Mobilisation of radiology personnel resulted in a tripling of the staff. Plain film and CT capacity was never exceeded despite deviations from the MAC strategy. An updated disaster management plan will require the radiologist to cancel non-head CTs performed in the ED until no additional MCI patients are expected. • Minimum acceptable care (MAC) should replace normal routines in mass casualty incidents. • MAC implied reduced use of imaging in the emergency department (ED). • CT in ED was restricted to suspected severe head injuries during MAC. • The radiologist should cancel all non-head CTs in the ED during MAC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lipnharski, I; Carranza, C; Quails, N
Purpose: To optimize adult head CT protocol by reducing dose to an appropriate level while providing CT images of diagnostic quality. Methods: Five cadavers were scanned from the skull base to the vertex using a routine adult head CT protocol (120 kVp, 270 mA, 0.75 s rotation, 0.5 mm × 32 detectors, 70.8 mGy CTDIvol) followed by seven reduced-dose protocols with varying combinations of reduced tube current, reduced rotation time, and increased detectors with CTDIvol ranging from 38.2 to 65.6 mGy. Organ doses were directly measured with 21 OSL dosimeters placed on the surface and implanted in the head bymore » a neurosurgeon. Two neuroradiologists assessed grey-white matter differentiation, fluid space, ventricular size, midline shift, brain mass, edema, ischemia, and skull fractures on a three point scale: (1) Unacceptable, (2) Borderline Acceptable, and (3) Acceptable. Results: For the standard scan, doses to the skin, lens of the eye, salivary glands, thyroid, and brain were 37.55 mGy, 49.65 mGy, 40.67 mGy, 4.63 mGy, and 27.33 mGy, respectively. Two cadavers had cerebral edema due to changing dynamics of postmortem effects, causing the grey-white matter differentiation to appear less distinct. Two cadavers with preserved grey-white matter received acceptable scores for all image quality features for the protocol with a CTDIvol of 57.3 mGy, allowing organ dose savings ranging from 34% to 45%. One cadaver allowed for greater dose reduction for the protocol with a CTDIvol of 42 mGy. Conclusion: Efforts to optimize scan protocol should consider both dose and clinical image quality. This is made possible with postmortem subjects, whose brains are similar to patients, allowing for an investigation of ideal scan parameters. Radiologists at our institution accepted scan protocols acquired with lower scan parameters, with CTDIvol values closer to the American College of Radiology’s (ACR) Achievable Dose level of 57 mGy.« less
Hame, Yrjo; Angelini, Elsa D; Hoffman, Eric A; Barr, R Graham; Laine, Andrew F
2014-07-01
The extent of pulmonary emphysema is commonly estimated from CT scans by computing the proportional area of voxels below a predefined attenuation threshold. However, the reliability of this approach is limited by several factors that affect the CT intensity distributions in the lung. This work presents a novel method for emphysema quantification, based on parametric modeling of intensity distributions and a hidden Markov measure field model to segment emphysematous regions. The framework adapts to the characteristics of an image to ensure a robust quantification of emphysema under varying CT imaging protocols, and differences in parenchymal intensity distributions due to factors such as inspiration level. Compared to standard approaches, the presented model involves a larger number of parameters, most of which can be estimated from data, to handle the variability encountered in lung CT scans. The method was applied on a longitudinal data set with 87 subjects and a total of 365 scans acquired with varying imaging protocols. The resulting emphysema estimates had very high intra-subject correlation values. By reducing sensitivity to changes in imaging protocol, the method provides a more robust estimate than standard approaches. The generated emphysema delineations promise advantages for regional analysis of emphysema extent and progression.
Emergency nurses' knowledge and experience with the triage process in Hunan Province, China.
Hammad, Karen; Peng, Lingli; Anikeeva, Olga; Arbon, Paul; Du, Huiyun; Li, Yinglan
2017-11-01
Triage is implemented to facilitate timely and appropriate treatment of patients, and is typically conducted by senior nurses. Triage accuracy and consistency across emergency departments remain a problem in mainland China. This study aimed to investigate the current status of triage practice and knowledge among emergency nurses in Changsha, Hunan Province, China. A sample of 300 emergency nurses was selected from 13 tertiary hospitals in Changsha and a total of 193 completed surveys were returned (response rate=64.3%). Surveys were circulated to head nurses, who then distributed them to nurses who met the selection criteria. Nurses were asked to complete the surveys and return them via dedicated survey return boxes that were placed in discreet locations to ensure anonymity. Just over half (50.8%) of participants reported receiving dedicated triage training, which was provided by their employer (38.6%), an education organisation (30.7%) or at a conference (26.1%). Approximately half (53.2%) reported using formal triage scales, which were predominantly 4-tier (43%) or 5-tier (34%). The findings highlight variability in triage practices and training of emergency nurses in Changsha. This has implications for the comparability of triage data and transferability of triage skills across hospitals. Copyright © 2017 Elsevier Ltd. All rights reserved.
Traditional Nurse Triage vs. Physician Tele-Presence in a Pediatric Emergency Department
Marconi, Greg P.; Chang, Todd; Pham, Phung K.; Grajower, Daniel N.; Nager, Alan L.
2014-01-01
Objectives To compare traditional nurse triage (TNT) in a Pediatric Emergency Department (PED) to physician tele-presence (PTP). Methods Prospective, 2×2 crossover study with random assignment using a sample of walk-in patients seeking care in a PED at a large, tertiary care children’s hospital, from May 2012 to January 2013. Outcomes of triage times, documentation errors, triage scores, and survey responses were compared between TNT and PTP. Comparison between PTP to actual treating PED physicians regarding the accuracy of ordering blood and urine tests, throat cultures, and radiologic imaging was also studied. Results Paired samples t-tests showed a statistically significant difference in triage time between TNT and PTP (p=0.03), but no significant difference in documentation errors (p=0.10). Triage scores of TNT were 71% accurate, compared to PTP, which were 95% accurate. Both parents and children had favorable scores regarding PTP and the majority indicated they would prefer PTP again at their next PED visit. PTP diagnostic ordering was comparable to the actual PED physician ordering, showing no statistical differences. Conclusions Utilizing physician tele-presence technology to remotely perform triage is a feasible alternative to traditional nurse triage, with no clinically significant differences in time, triage scores, errors and patient and parent satisfaction. PMID:24445223
Emergency department triage: an ethical analysis
2011-01-01
Background Emergency departments across the globe follow a triage system in order to cope with overcrowding. The intention behind triage is to improve the emergency care and to prioritize cases in terms of clinical urgency. Discussion In emergency department triage, medical care might lead to adverse consequences like delay in providing care, compromise in privacy and confidentiality, poor physician-patient communication, failing to provide the necessary care altogether, or even having to decide whose life to save when not everyone can be saved. These consequences challenge the ethical quality of emergency care. This article provides an ethical analysis of "routine" emergency department triage. The four principles of biomedical ethics - viz. respect for autonomy, beneficence, nonmaleficence and justice provide the starting point and help us to identify the ethical challenges of emergency department triage. However, they do not offer a comprehensive ethical view. To address the ethical issues of emergency department triage from a more comprehensive ethical view, the care ethics perspective offers additional insights. Summary We integrate the results from the analysis using four principles of biomedical ethics into care ethics perspective on triage and propose an integrated clinically and ethically based framework of emergency department triage planning, as seen from a comprehensive ethics perspective that incorporates both the principles-based and care-oriented approach. PMID:21982119
Computed tomography and clinical outcome in patients with severe traumatic brain injury.
Stenberg, Maud; Koskinen, Lars-Owe D; Jonasson, Per; Levi, Richard; Stålnacke, Britt-Marie
2017-01-01
To study: (i) acute computed tomography (CT) characteristics and clinical outcome; (ii) clinical course and (iii) Corticosteroid Randomisation after Significant Head Injury acute calculator protocol (CRASH) model and clinical outcome in patients with severe traumatic brain injury (sTBI). Initial CT (CT i ) and CT 24 hours post-trauma (CT 24 ) were evaluated according to Marshall and Rotterdam classifications. Rancho Los Amigos Cognitive Scale-Revised (RLAS-R) and Glasgow Outcome Scale Extended (GOSE) were assessed at three months and one year post-trauma. The prognostic value of the CRASH model was evaluated. Thirty-seven patients were included. Marshall CT i and CT 24 were significantly correlated with RLAS-R at three months. Rotterdam CT 24 was significantly correlated with GOSE at three months. RLAS-R and the GOSE improved significantly from three months to one year. CRASH predicted unfavourable outcome at six months for 81% of patients with bad outcome and for 85% of patients with favourable outcome according to GOSE at one year. Neither CT nor CRASH yielded clinically useful predictions of outcome at one year post-injury. The study showed encouragingly many instances of significant recovery in this population of sTBI. The combination of lack of reliable prognostic indicators and favourable outcomes supports the case for intensive acute management and rehabilitation as the default protocol in the cases of sTBI.
Sultan, H; Boyle, A; Pereira, M; Antoun, N; Maimaris, C
2004-01-01
Objective: : In 2002 a new protocol was introduced based on the Canadian CT rules. Before this the Royal College of Surgeons "Galasko" report guidelines had been followed. This study evaluates the effects of the protocol and discusses the impact of the implementation of the NICE head injury guidelines—also based on the Canadian CT rules. Methods: A "before and after" study was undertaken, using data from accident and emergency cards and hospital notes of adult patients with head injuries presenting to the emergency department over seven months in 2001 and nine months in 2002. The two groups were compared to see how rates of computed tomography (CT), admission for observation, discharge, and skull radiography had changed after introduction of the protocol. Results: : Head CT rates in patients with minor head injuries (MHI) increased significantly from 47 of 330 (14%) to 58 of 267 (20%) (p<0.05). There were also significantly increased rates of admission for observation, from 111 (34%) to 119 (45%). Skull radiography rates fell considerably from 33% of all patients with head injuries in 2001 to 1.6% in 2002, without any adverse effect. Conclusions: This study shows that it is possible to replace the current practice in the UK of risk stratification of adult MHI based on skull radiography, with slightly modified versions of the Canadian CT rule/NICE guidelines. This will result in a large reduction in skull radiography and will be associated with modest increases in CT and admissions rates. If introduction of the NICE guideline is to be realistic, the study suggests that it will not be cost neutral. PMID:15208222
Jones, Courtney Marie Cora; Cushman, Jeremy T; Lerner, E Brooke; Fisher, Susan G; Seplaki, Christopher L; Veazie, Peter J; Wasserman, Erin B; Dozier, Ann; Shah, Manish N
2016-01-01
We describe the decision-making process used by emergency medical services (EMS) providers in order to understand how 1) injured patients are evaluated in the prehospital setting; 2) field triage criteria are applied in-practice; and 3) selection of a destination hospital is determined. We conducted separate focus groups with advanced and basic life support providers from rural and urban/suburban regions. Four exploratory focus groups were conducted to identify overarching themes and five additional confirmatory focus groups were conducted to verify initial focus group findings and provide additional detail regarding trauma triage decision-making and application of field triage criteria. All focus groups were conducted by a public health researcher with formal training in qualitative research. A standardized question guide was used to facilitate discussion at all focus groups. All focus groups were audio-recorded and transcribed. Responses were coded and categorized into larger domains to describe how EMS providers approach trauma triage and apply the Field Triage Decision Scheme. We conducted 9 focus groups with 50 EMS providers. Participants highlighted that trauma triage is complex and there is often limited time to make destination decisions. Four overarching domains were identified within the context of trauma triage decision-making: 1) initial assessment; 2) importance of speed versus accuracy; 3) usability of current field triage criteria; and 4) consideration of patient and emergency care system-level factors. Field triage is a complex decision-making process which involves consideration of many patient and system-level factors. The decision model presented in this study suggests that EMS providers place significant emphasis on speed of decisions, relying on initial impressions and immediately observable information, rather than precise measurement of vital signs or systematic application of field triage criteria.
[Clinical evaluation of triage as drug-of-abuse test kit].
Yoshioka, Toshiharu; Kohriyama, Kazuaki; Kondo, Rumiko; Goto, Kyoko; Yashiki, Mikio
2003-01-01
There are about 60,000 chemical substances which may cause poisoning. Identifying the cause substances is, therefore, very important for patient at emergency department. Triage is an immunoassay kit for the qualitative test for the metabolites of 8 major abuse drugs in urine. We assessed the usefullness of Triage on two patient groups. The first Group consists of the patients considered having not taken substances at initial diagnosis; the second Group consists of the patients considered having taken substances. The result are as follows. 1) The rate of Triage positive patients in the first Group were: attempt-suicide 23%, coma 24%, shock 10%, trauma 7%, respectively. Except for the habitually used medicine, narcotic and stimulant drugs were detected. In the first Group, negative result of Triage was effective in diagnosing the patients as not poisoned, excluding the possitivity of 8 major drugs usage. 2) The rate of Triage positive patients in the second Group were very high: attempt-suicide 77%, coma 51%, shock 57%, trauma 30%, respectively, showing mostly any of 8 major drugs were the cause of poisoning. In the second Group, positive result of Triage was effective in diagnosing the patient as poisoning or as coexisting poisoning with other diseases. 3) The specificity of Triage diagnosis in the first Group was 80% (113/142). The specificity and the sensitivity in the second Group were 64% (50/78) and 97% (74/76), respectively. These results means that Triage is very useful for diagnosis on 8 major drugs poisoning. 4) Triage is efficient for identifying the cause substances in drug poisoning and, therefore, can save medical expense. Triage is a very useful test kit at emergency department.
Cicero, Mark Xavier; Whitfill, Travis; Overly, Frank; Baird, Janette; Walsh, Barbara; Yarzebski, Jorge; Riera, Antonio; Adelgais, Kathleen; Meckler, Garth D; Baum, Carl; Cone, David Christopher; Auerbach, Marc
2017-01-01
Paramedics and emergency medical technicians (EMTs) triage pediatric disaster victims infrequently. The objective of this study was to measure the effect of a multiple-patient, multiple-simulation curriculum on accuracy of pediatric disaster triage (PDT). Paramedics, paramedic students, and EMTs from three sites were enrolled. Triage accuracy was measured three times (Time 0, Time 1 [two weeks later], and Time 2 [6 months later]) during a disaster simulation, in which high and low fidelity manikins and actors portrayed 10 victims. Accuracy was determined by participant triage decision concordance with predetermined expected triage level (RED [Immediate], YELLOW [Delayed], GREEN [Ambulatory], BLACK [Deceased]) for each victim. Between Time 0 and Time 1, participants completed an interactive online module, and after each simulation there was an individual debriefing. Associations between participant level of training, years of experience, and enrollment site were determined, as were instances of the most dangerous mistriage, when RED and YELLOW victims were triaged BLACK. The study enrolled 331 participants, and the analysis included 261 (78.9%) participants who completed the study, 123 from the Connecticut site, 83 from Rhode Island, and 55 from Massachusetts. Triage accuracy improved significantly from Time 0 to Time 1, after the educational interventions (first simulation with debriefing, and an interactive online module), with a median 10% overall improvement (p < 0.001). Subgroup analyses showed between Time 0 and Time 1, paramedics and paramedic students improved more than EMTs (p = 0.002). Analysis of triage accuracy showed greatest improvement in overall accuracy for YELLOW triage patients (Time 0 50% accurate, Time1 100%), followed by RED patients (Time 0 80%, Time 1 100%). There was no significant difference in accuracy between Time 1 and Time 2 (p = 0.073). This study shows that the multiple-victim, multiple-simulation curriculum yields a durable 10% improvement in simulated triage accuracy. Future iterations of the curriculum can target greater improvements in EMT triage accuracy.
van't Hoog, Anna H; Cobelens, Frank; Vassall, Anna; van Kampen, Sanne; Dorman, Susan E; Alland, David; Ellner, Jerrold
2013-01-01
High costs are a limitation to scaling up the Xpert MTB/RIF assay (Xpert) for the diagnosis of tuberculosis in resource-constrained settings. A triaging strategy in which a sensitive but not necessarily highly specific rapid test is used to select patients for Xpert may result in a more affordable diagnostic algorithm. To inform the selection and development of particular diagnostics as a triage test we explored combinations of sensitivity, specificity and cost at which a hypothetical triage test will improve affordability of the Xpert assay. In a decision analytical model parameterized for Uganda, India and South Africa, we compared a diagnostic algorithm in which a cohort of patients with presumptive TB received Xpert to a triage algorithm whereby only those with a positive triage test were tested by Xpert. A triage test with sensitivity equal to Xpert, 75% specificity, and costs of US$5 per patient tested reduced total diagnostic costs by 42% in the Uganda setting, and by 34% and 39% respectively in the India and South Africa settings. When exploring triage algorithms with lower sensitivity, the use of an example triage test with 95% sensitivity relative to Xpert, 75% specificity and test costs $5 resulted in similar cost reduction, and was cost-effective by the WHO willingness-to-pay threshold compared to Xpert for all in Uganda, but not in India and South Africa. The gain in affordability of the examined triage algorithms increased with decreasing prevalence of tuberculosis among the cohort. A triage test strategy could potentially improve the affordability of Xpert for TB diagnosis, particularly in low-income countries and with enhanced case-finding. Tests and markers with lower accuracy than desired of a diagnostic test may fall within the ranges of sensitivity, specificity and cost required for triage tests and be developed as such.
Causes and occurrences of interruptions during ED triage.
Johnson, Kimberly D; Motavalli, Michele; Gray, Dean; Kuehn, Connie
2014-09-01
Interruptions have been shown to cause errors and delays in the treatment of emergency patients and pose a real threat during the triage process. Missteps during the triage assessment can send a patient down the wrong treatment path and lead to delays. The purpose of this project was to identify the types and frequency of interruptions during the ED triage interview process. A focus group of emergency nurses was organized to identify the types of interruptions that commonly occur during the triage interview. These interruptions would be validated through observations in triage. A tally sheet was developed and implemented to determine how often each interruption occurred during an 8-hour shift. Triage nurses completed the tally sheets while working the first shift (7 am to 3 pm). This shift was selected because patient intake in the US Department of Veterans Affairs Emergency Department is highest during this time. The categories of interruptions identified included provision of conveniences to visitors, coworker-related interruptions, patient care-related interruptions, locating of family members in the emergency department, and other miscellaneous interruptions. Tally sheets were completed by the triage nurses during 10 shifts. On average, triage nurses were interrupted 48.2 times during an 8-hour shift (7 interruptions per hour). After reviewing the data, we found that only 22% of interruptions were related to patient care. More frequently, the causes of interruptions were not related to patient care: opening the door (33%), providing conveniences to visitors (21%), waiting patients or family members asking "How much longer?" (14%), and other causes (10%). Frequent interruptions can interfere with concentration and may affect patient care. Non-patient care-related interruptions not only can be frustrating to the triage nurse but also can be offensive to triage patients; they ultimately delay care and may even affect the quality of care. However, because scarce research is available regarding interruptions during ED triage, the effects on patient outcomes are unclear. Additional research needs to be conducted to explore the causes and effects of interruptions to the triage process. Copyright © 2014 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.
Liu, Jenny; Masiello, Italo; Ponzer, Sari; Farrokhnia, Nasim
2018-04-19
To determine the impact on emergency department (ED) throughput times and proportion of patients who leave without being seen by a physician (LWBS) of two triage interventions, where comprehensive nurse-led triage was first replaced by senior physician-led triage and then by interprofessional teamwork. Single-centre before-and-after study. Adult ED of a Swedish urban hospital. Patients arriving on weekdays 08:00 to 21:00 during three 1-year periods in the interval May 2012 to November 2015. A total of 185 806 arrivals were included. Senior physicians replaced triage nurses May 2013 to May 2014. Interprofessional teamwork replaced the triage process on weekdays 08:00 to 21:00 November 2014 to November 2015. Primary outcomes were the median time to physician (TTP) and the median length of stay (LOS). Secondary outcome was the LWBS rate. The crude median LOS was shortest for teamwork, 228 min (95% CI 226.4 to 230.5) compared with 232 min (95% CI 230.8 to 233.9) for nurse-led and 250 min (95% CI 248.5 to 252.6) for physician-led triage. The adjusted LOS for the teamwork period was 16 min shorter than for nurse-led triage and 23 min shorter than for physician-led triage. The median TTP was shortest for physician-led triage, 56 min (95% CI 54.5 to 56.6) compared with 116 min (95% CI 114.4 to 117.5) for nurse-led triage and 74 min (95% CI 72.7 to 74.8) for teamwork. The LWBS rate was 1.9% for nurse-led triage, 1.2% for physician-led triage and 3.2% for teamwork. All outcome measure differences had two-tailed p values<0.01. Interprofessional teamwork had the shortest length of stay, a shorter time to physician than nurse-led triage, but a higher LWBS rate. Interprofessional teamwork may be a useful approach to reducing ED throughput times. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Estimation of radiation cancer risk in CT-KUB
NASA Astrophysics Data System (ADS)
Karim, M. K. A.; Hashim, S.; Bakar, K. A.; Bradley, D. A.; Ang, W. C.; Bahrudin, N. A.; Mhareb, M. H. A.
2017-08-01
The increased demand for computed tomography (CT) in radiological scanning examinations raises the question of a potential health impact from the associated radiation exposures. Focusing on CT kidney-ureter-bladder (CT-KUB) procedures, this work was aimed at determining organ equivalent dose using a commercial CT dose calculator and providing an estimate of cancer risks. The study, which included 64 patients (32 males and 32 females, mean age 55.5 years and age range 30-80 years), involved use of a calibrated CT scanner (Siemens-Somatom Emotion 16-slice). The CT exposures parameter including tube potential, pitch factor, tube current, volume CT dose index (CTDIvol) and dose-length product (DLP) were recorded and analyzed using CT-EXPO (Version 2.3.1, Germany). Patient organ doses, including for stomach, liver, colon, bladder, red bone marrow, prostate and ovaries were calculated and converted into cancer risks using age- and sex-specific data published in the Biological Effects of Ionizing Radiation (BEIR) VII report. With a median value scan range of 36.1 cm, the CTDIvol, DLP, and effective dose were found to be 10.7 mGy, 390.3 mGy cm and 6.2 mSv, respectively. The mean cancer risks for males and females were estimated to be respectively 25 and 46 out of 100,000 procedures with effective doses between 4.2 mSv and 10.1 mSv. Given the increased cancer risks from current CT-KUB procedures compared to conventional examinations, we propose that the low dose protocols for unenhanced CT procedures be taken into consideration before establishing imaging protocols for CT-KUB.
Standardizing CT lung density measure across scanner manufacturers.
Chen-Mayer, Huaiyu Heather; Fuld, Matthew K; Hoppel, Bernice; Judy, Philip F; Sieren, Jered P; Guo, Junfeng; Lynch, David A; Possolo, Antonio; Fain, Sean B
2017-03-01
Computed Tomography (CT) imaging of the lung, reported in Hounsfield Units (HU), can be parameterized as a quantitative image biomarker for the diagnosis and monitoring of lung density changes due to emphysema, a type of chronic obstructive pulmonary disease (COPD). CT lung density metrics are global measurements based on lung CT number histograms, and are typically a quantity specifying either the percentage of voxels with CT numbers below a threshold, or a single CT number below which a fixed relative lung volume, nth percentile, falls. To reduce variability in the density metrics specified by CT attenuation, the Quantitative Imaging Biomarkers Alliance (QIBA) Lung Density Committee has organized efforts to conduct phantom studies in a variety of scanner models to establish a baseline for assessing the variations in patient studies that can be attributed to scanner calibration and measurement uncertainty. Data were obtained from a phantom study on CT scanners from four manufacturers with several protocols at various tube potential voltage (kVp) and exposure settings. Free from biological variation, these phantom studies provide an assessment of the accuracy and precision of the density metrics across platforms solely due to machine calibration and uncertainty of the reference materials. The phantom used in this study has three foam density references in the lung density region, which, after calibration against a suite of Standard Reference Materials (SRM) foams with certified physical density, establishes a HU-electron density relationship for each machine-protocol. We devised a 5-step calibration procedure combined with a simplified physical model that enabled the standardization of the CT numbers reported across a total of 22 scanner-protocol settings to a single energy (chosen at 80 keV). A standard deviation was calculated for overall CT numbers for each density, as well as by scanner and other variables, as a measure of the variability, before and after the standardization. In addition, a linear mixed-effects model was used to assess the heterogeneity across scanners, and the 95% confidence interval of the mean CT number was evaluated before and after the standardization. We show that after applying the standardization procedures to the phantom data, the instrumental reproducibility of the CT density measurement of the reference foams improved by more than 65%, as measured by the standard deviation of the overall mean CT number. Using the lung foam that did not participate in the calibration as a test case, a mixed effects model analysis shows that the 95% confidence intervals are [-862.0 HU, -851.3 HU] before standardization, and [-859.0 HU, -853.7 HU] after standardization to 80 keV. This is in general agreement with the expected CT number value at 80 keV of -855.9 HU with 95% CI of [-857.4 HU, -854.5 HU] based on the calibration and the uncertainty in the SRM certified density. This study provides a quantitative assessment of the variations expected in CT lung density measures attributed to non-biological sources such as scanner calibration and scanner x-ray spectrum and filtration. By removing scanner-protocol dependence from the measured CT numbers, higher accuracy and reproducibility of quantitative CT measures were attainable. The standardization procedures developed in study may be explored for possible application in CT lung density clinical data. © 2017 American Association of Physicists in Medicine.
Triage: a literature review 1985-1993.
McDonald, L; Butterworth, T; Yates, D W
1995-10-01
Following an extensive literature review of Accident and Emergency (A & E) nursing from 1985-1993, the authors focused upon triage. A wide range of issues related to triage and its use in A & E departments are examined. An appendix is included to clarify major research finds in this area. Many of the claims made regarding triage require further investigation.
Novel SPECT Technologies and Approaches in Cardiac Imaging
Slomka, Piotr; Hung, Guang-Uei; Germano, Guido; Berman, Daniel S.
2017-01-01
Recent novel approaches in myocardial perfusion single photon emission CT (SPECT) have been facilitated by new dedicated high-efficiency hardware with solid-state detectors and optimized collimators. New protocols include very low-dose (1 mSv) stress-only, two-position imaging to mitigate attenuation artifacts, and simultaneous dual-isotope imaging. Attenuation correction can be performed by specialized low-dose systems or by previously obtained CT coronary calcium scans. Hybrid protocols using CT angiography have been proposed. Image quality improvements have been demonstrated by novel reconstructions and motion correction. Fast SPECT acquisition facilitates dynamic flow and early function measurements. Image processing algorithms have become automated with virtually unsupervised extraction of quantitative imaging variables. This automation facilitates integration with clinical variables derived by machine learning to predict patient outcome or diagnosis. In this review, we describe new imaging protocols made possible by the new hardware developments. We also discuss several novel software approaches for the quantification and interpretation of myocardial perfusion SPECT scans. PMID:29034066
Protocolized treatment is associated with decreased organ dysfunction in pediatric severe sepsis
Balamuth, Fran; Weiss, Scott L.; Fitzgerald, Julie C.; Hayes, Katie; Centkowski, Sierra; Chilutti, Marianne; Grundmeier, Robert W.; Lavelle, Jane; Alpern, Elizabeth R.
2016-01-01
Objective To determine whether treatment with a protocolized sepsis guideline in the emergency department (ED) was associated with a lower burden of organ dysfunction (OD) by hospital day 2 compared to non-protocolized usual care in pediatric patients with severe sepsis. Design Retrospective cohort study Setting Tertiary care children’s hospital from January 1, 2012–March 31, 2014. Measurements and Main Results Subjects with international consensus defined severe sepsis and pediatric intensive care unit (PICU) admission within 24 hours of ED arrival were included. The exposure was the use of a protocolized ED sepsis guideline. The primary outcome was complete resolution of OD by hospital day 2. One hundred eighty nine subjects were identified during the study period. Of these, 121 (64%) were treated with the protocolized ED guideline and 68 were not. There were no significant differences between the groups in age, sex, race, number of comorbid conditions, ED triage level, or OD on arrival to the ED. Patients treated with protocolized ED care were more likely to be free of OD on hospital day 2 after controlling for sex, comorbid condition, indwelling central venous catheter, PIM-2 score, and timing of antibiotics and intravenous fluids (adjusted OR 4.2, 95% CI 1.7, 10.4). Conclusions Use of a protocolized ED sepsis guideline was independently associated with resolution of OD by hospital day 2 compared to non-protocolized usual care. These data indicate that morbidity outcomes in children can be improved with the use of protocolized care. PMID:27455114
Emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma.
Stengel, Dirk; Rademacher, Grit; Ekkernkamp, Axel; Güthoff, Claas; Mutze, Sven
2015-09-14
Ultrasonography (performed by means of a four-quadrant, focused assessment of sonography for trauma (FAST)) is regarded as a key instrument for the initial assessment of patients with suspected blunt abdominal and thoraco-abdominal trauma in the emergency department setting. FAST has a high specificity but low sensitivity in detecting and excluding visceral injuries. Proponents of FAST argue that ultrasound-based clinical pathways enhance the speed of primary trauma assessment, reduce the number of unnecessary multi-detector computed tomography (MDCT) scans, and enable quicker triage to surgical and non-surgical care. Given the proven accuracy, increasing availability of, and indication for, MDCT among patients with blunt abdominal and multiple injuries, we aimed to compile the best available evidence of the use of FAST-based assessment compared with other primary trauma assessment protocols. To assess the effects of diagnostic algorithms using ultrasonography including in FAST examinations in the emergency department in relation to the early, late, and overall mortality of patients with suspected blunt abdominal trauma. The most recent search was run on 30th June 2015. We searched the Cochrane Injuries Group Specialised Register, The Cochrane Library, MEDLINE (OvidSP), EMBASE (OvidSP), ISI Web of Science (SCI-EXPANDED, SSCI, CPCI-S, and CPSI-SSH), clinical trials registers, and screened reference lists. Trial authors were contacted for further information and individual patient data. We included randomised controlled trials (RCTs). Participants were patients with blunt torso, abdominal, or multiple trauma undergoing diagnostic investigations for abdominal organ injury. The intervention was diagnostic algorithms comprising emergency ultrasonography (US). The control was diagnostic algorithms without US examinations (for example, primary computed tomography (CT) or diagnostic peritoneal lavage (DPL)). Outcomes were mortality, use of CT or invasive procedures (DPL, laparoscopy, laparotomy), and cost-effectiveness. Two authors (DS and CG) independently selected trials for inclusion, assessed methodological quality, and extracted data. Methodological quality was assessed using the Cochrane Collaboration risk of bias tool. Where possible, data were pooled and relative risks (RRs), risk differences (RDs), and weighted mean differences, each with 95% confidence intervals (CIs), were calculated by fixed-effect or random-effects models as appropriate. We identified four studies meeting our inclusion criteria. Overall, trials were of poor to moderate methodological quality. Few trial authors responded to our written inquiries seeking to resolve controversial issues and to obtain individual patient data. Strong heterogeneity amongst the trials prompted discussion between the review authors as to whether the data should or should not be pooled; we decided in favour of a quantitative synthesis to provide a rough impression about the effect sizes achievable with US-based triage algorithms. We pooled mortality data from three trials involving 1254 patients; the RR in favour of the FAST arm was 1.00 (95% CI 0.50 to 2.00). FAST-based pathways reduced the number of CT scans (random-effects model RD -0.52, 95% CI -0.83 to -0.21), but the meaning of this result was unclear. The experimental evidence justifying FAST-based clinical pathways in diagnosing patients with suspected abdominal or multiple blunt trauma remains poor. Because of strong heterogeneity between the trial results, the quantitative information provided by this review may only be used in an exploratory fashion. It is unlikely that FAST will ever be investigated by means of a confirmatory, large-scale RCT in the future. Thus, this Cochrane Review may be regarded as a review which provides the best available evidence for clinical practice guidelines and management recommendations. It can only be concluded from the few head-to-head studies that negative US scans are likely to reduce the incidence of MDCT scans which, given the low sensitivity of FAST (or reliability of negative results), may adversely affect the diagnostic yield of the trauma survey. At best, US has no negative impact on mortality or morbidity. Assuming that major blunt abdominal or multiple trauma is associated with 15% mortality and a CT-based diagnostic work-up is considered the current standard of care, 874, 3495, or 21,838 patients are needed per intervention group to demonstrate non-inferiority of FAST to CT-based algorithms with non-inferiority margins of 5%, 2.5%, and 1%, power of 90%, and a type-I error alpha of 5%.
Saade, Charbel; Mayat, Ahmad; El-Merhi, Fadi
2016-01-01
Matching contrast injection timing with vessel dynamics significantly improves vessel opacification and reduces contrast dose in the assessment of pulmonary embolism during computed tomography (CT) pulmonary angiography. The aim of this study was to investigate opacification of the pulmonary vasculature (PV) during CT pulmonary angiography using a patient-specific contrast formula (PSCF) and exponentially decelerated contrast media (EDCM) injection rate. Institutional review board approved this retrospective study. Computed tomography pulmonary angiography was performed on 200 patients with suspected pulmonary embolism using a 64-channel CT scanner. Patient demographics were equally distributed. Patients were randomly assigned to 2 equal protocol groups: protocol A used a PSCF, and protocol B involved the use of a PSCF combined with EDCM. The mean cross-sectional opacification profile of 8 central and 11 peripheral PVs were measured for each patient, and arteriovenous contrast ratio was calculated. Protocols were compared using Mann-Whitney U nonparametric statistics. Jackknife alternative free-response receiver operating characteristic analyses were used to assess diagnostic efficacy. Interobserver variations were investigated using kappa methods. A number of pulmonary arteries demonstrated increases in opacification (P < 0.02) for protocol B compared with A, whereas opacification in all veins was reduced in protocol B (P < 0.03). Subsequently, increased arteriovenous contrast ratio in protocol B compared with A was observed at all anatomic locations (P < 0.0002). An increase in jackknife alternative free-response receiver operating characteristic figure of merit (P < 0.0002) and interobserver variation was observed with protocol B compared with protocol A (κ = 0.3-0.73). Mean contrast volume was reduced in protocol B (29 [4] mL) compared with protocol A (33 [9] mL). Mean effective radiation dose in protocol B (1.2 [0.4] mSv) was reduced by 14% compared with protocol A (1.4 [0.6] mSv). Significant improvements in visualization of the PV can be achieved with a low contrast volume using an EDCM and PSCF. The reduced risk of cancer induction is highlighted.
Gariani, Joanna; Martin, Steve P; Botsikas, Diomidis; Becker, Christoph D; Montet, Xavier
2018-06-14
To compare radiation dose and image quality of thoracoabdominal scans obtained with a high-pitch protocol (pitch 3.2) and iterative reconstruction (Sinogram Affirmed Iterative Reconstruction) in comparison to standard pitch reconstructed with filtered back projection (FBP) using dual source CT. 114 CT scans (Somatom Definition Flash, Siemens Healthineers, Erlangen, Germany), 39 thoracic scans, 54 thoracoabdominal scans and 21 abdominal scans were performed. Analysis of three protocols was undertaken; pitch of 1 reconstructed with FBP, pitch of 3.2 reconstructed with SAFIRE, pitch of 3.2 with stellar detectors reconstructed with SAFIRE. Objective and subjective image analysis were performed. Dose differences of the protocols used were compared. Dose was reduced when comparing scans with a pitch of 1 reconstructed with FBP to high-pitch scans with a pitch of 3.2 reconstructed with SAFIRE with a reduction of volume CT dose index of 75% for thoracic scans, 64% for thoracoabdominal scans and 67% for abdominal scans. There was a further reduction after the implementation of stellar detectors reflected in a reduction of 36% of the dose-length product for thoracic scans. This was not at the detriment of image quality, contrast-to-noise ratio, signal-to-noise ratio and the qualitative image analysis revealed a superior image quality in the high-pitch protocols. The combination of a high pitch protocol with iterative reconstruction allows significant dose reduction in routine chest and abdominal scans whilst maintaining or improving diagnostic image quality, with a further reduction in thoracic scans with stellar detectors. Advances in knowledge: High pitch imaging with iterative reconstruction is a tool that can be used to reduce dose without sacrificing image quality.
Optimizing radiologist e-prescribing of CT oral contrast agent using a protocoling portal.
Wasser, Elliot J; Galante, Nicholas J; Andriole, Katherine P; Farkas, Cameron; Khorasani, Ramin
2013-12-01
The purpose of this study is to quantify the time expenditure associated with radiologist ordering of CT oral contrast media when using an integrated protocoling portal and to determine radiologists' perceptions of the ordering process. This prospective study was performed at a large academic tertiary care facility. Detailed timing information for CT inpatient oral contrast orders placed via the computerized physician order entry (CPOE) system was gathered over a 14-day period. Analyses evaluated the amount of physician time required for each component of the ordering process. Radiologists' perceptions of the ordering process were assessed by survey. Descriptive statistics and chi-square analysis were performed. A total of 96 oral contrast agent orders were placed by 13 radiologists during the study period. The average time necessary to create a protocol for each case was 40.4 seconds (average range by subject, 20.0-130.0 seconds; SD, 37.1 seconds), and the average total time to create and sign each contrast agent order was 27.2 seconds (range, 10.0-50.0 seconds; SD, 22.4 seconds). Overall, 52.5% (21/40) of survey respondents indicated that radiologist entry of oral contrast agent orders improved patient safety. A minority of respondents (15% [6/40]) indicated that contrast agent order entry was either very or extremely disruptive to workflow. Radiologist e-prescribing of CT oral contrast agents using CPOE can be embedded in a protocol workflow. Integration of health IT tools can help to optimize user acceptance and adoption.
How will military/civilian coordination work for reception of mass casualties from overseas?
Mackenzie, Colin; Donohue, John; Wasylina, Philip; Cullum, Woodrow; Hu, Peter; Lam, David M
2009-01-01
In Maryland, there have been no military/civilian training exercises of the Medical Mutual Aid Agreement for >20 years. The aims of this paper are to describe the National Disaster Medical System (NDMS), to coordinate military and civilian medical mutual aid in response to arrival of overseas mass casualties, and to evaluate the mass-casualty reception and bed "surge" capacity of Maryland NDMS Hospitals. Three tabletop exercises and a functional exercise were performed using a simulated, overseas, military mass-casualty event. The first tabletop exercise was with military and civilian NMDS partners. The second tested the revised NDMS activation plan. The third exercised the Authorities of State Emergency Medical System and Walter Reed Army Medical Center Directors of Emergency Medicine over Maryland NDMS hospitals, and their Medical Mutual Aid Agreement. The functional exercise used Homeland Security Exercise Evaluation Program tools to evaluate reception, triage, staging, and transportation of 160 notional patients (including 20 live, moulaged "patients") and one canine. The first tabletop exercise identified deficiencies in operational protocols for military/civilian mass-casualty reception, triage, treatment, and problems with sharing a Unified Command. The second found improvements in the revised NDMS activation plan. The third informed expectations for NDMS hospitals. In the functional exercise, all notional patients were received, triaged, dispatched, and accounted in military and five civilian hospitals within two hours. The canine revealed deficiencies in companion/military animal reception, holding, treatment, and evacuation. Three working groups were suggested: (1) to ensure 100% compliance with triage tags, patient accountability, and return of equipment used in mass casualty events and exercises; (2) to investigate making information technology and imaging networks available for Emergency Operation Centers and Incident Command; and (3) to establish NDMS training, education, and evaluation to further integrate and support civil-military operations. The exercises facilitated military/state inter-agency cooperation, resulting in revisions to the Maryland Emergency Operations Plan across all key state emergency response agencies. The recommendations from these exercises likely apply to the vast majority of NDMS activities in the US.
Dreizin, David; Nam, Arthur J; Hirsch, Jeffrey; Bernstein, Mark P
2018-06-20
This article reviews the conceptual framework, available evidence, and practical considerations pertaining to nascent and emerging advances in patient-centered CT-imaging and CT-guided surgery for maxillofacial trauma. These include cinematic rendering-a novel method for advanced 3D visualization, incorporation of quantitative CT imaging into the assessment of orbital fractures, low-dose CT imaging protocols made possible with contemporary scanners and reconstruction techniques, the rapidly growing use of cone-beam CT, virtual fracture reduction with design software for surgical pre-planning, the use of 3D printing for fabricating models and implants, and new avenues in CT-guided computer-aided surgery.
Tanabe, Yuki; Kido, Teruhito; Kurata, Akira; Fukuyama, Naoki; Yokoi, Takahiro; Kido, Tomoyuki; Uetani, Teruyoshi; Vembar, Mani; Dhanantwari, Amar; Tokuyasu, Shinichi; Yamashita, Natsumi; Mochizuki, Teruhito
2017-10-01
We evaluated the image quality and diagnostic performance of late iodine enhancement computed tomography (LIE-CT) with knowledge-based iterative model reconstruction (IMR) for the detection of myocardial infarction (MI) in comparison with late gadolinium enhancement magnetic resonance imaging (LGE-MRI). The study investigated 35 patients who underwent a comprehensive cardiac CT protocol and LGE-MRI for the assessment of coronary artery disease. The CT protocol consisted of stress dynamic myocardial CT perfusion, coronary CT angiography (CTA) and LIE-CT using 256-slice CT. LIE-CT scans were acquired 5 min after CTA without additional contrast medium and reconstructed with filtered back projection (FBP), a hybrid iterative reconstruction (HIR), and IMR. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed. Sensitivity and specificity of LIE-CT for detecting MI were assessed according to the 16-segment model. Image quality scores, and diagnostic performance were compared among LIE-CT with FBP, HIR and IMR. Among the 35 patients, 139 of 560 segments showed MI in LGE-MRI. On LIE-CT with FBP, HIR, and IMR, the median SNRs were 2.1, 2.9, and 6.1; and the median CNRs were 1.7, 2.2, and 4.7, respectively. Sensitivity and specificity were 56 and 93% for FBP, 62 and 91% for HIR, and 80 and 91% for IMR. LIE-CT with IMR showed the highest image quality and sensitivity (p < 0.05). The use of IMR enables significant improvement of image quality and diagnostic performance of LIE-CT for detecting MI in comparison with FBP and HIR.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brady, Samuel L., E-mail: samuel.brady@stjude.org; Shulkin, Barry L.
2015-02-15
Purpose: To develop ultralow dose computed tomography (CT) attenuation correction (CTAC) acquisition protocols for pediatric positron emission tomography CT (PET CT). Methods: A GE Discovery 690 PET CT hybrid scanner was used to investigate the change to quantitative PET and CT measurements when operated at ultralow doses (10–35 mA s). CT quantitation: noise, low-contrast resolution, and CT numbers for 11 tissue substitutes were analyzed in-phantom. CT quantitation was analyzed to a reduction of 90% volume computed tomography dose index (0.39/3.64; mGy) from baseline. To minimize noise infiltration, 100% adaptive statistical iterative reconstruction (ASiR) was used for CT reconstruction. PET imagesmore » were reconstructed with the lower-dose CTAC iterations and analyzed for: maximum body weight standardized uptake value (SUV{sub bw}) of various diameter targets (range 8–37 mm), background uniformity, and spatial resolution. Radiation dose and CTAC noise magnitude were compared for 140 patient examinations (76 post-ASiR implementation) to determine relative dose reduction and noise control. Results: CT numbers were constant to within 10% from the nondose reduced CTAC image for 90% dose reduction. No change in SUV{sub bw}, background percent uniformity, or spatial resolution for PET images reconstructed with CTAC protocols was found down to 90% dose reduction. Patient population effective dose analysis demonstrated relative CTAC dose reductions between 62% and 86% (3.2/8.3–0.9/6.2). Noise magnitude in dose-reduced patient images increased but was not statistically different from predose-reduced patient images. Conclusions: Using ASiR allowed for aggressive reduction in CT dose with no change in PET reconstructed images while maintaining sufficient image quality for colocalization of hybrid CT anatomy and PET radioisotope uptake.« less
Contemporary Obstetric Triage.
Sandy, Edward Allen; Kaminski, Robert; Simhan, Hygriv; Beigi, Richard
2016-03-01
The role of obstetric triage in the care of pregnant women has expanded significantly. Factors driving this change include the Emergency Medical Treatment and Active Labor Act, improved methods of testing for fetal well-being, increasing litigation risk, and changes in resident duty hour guidelines. The contemporary obstetric triage facility must have processes in place to provide a medical screening examination that complies with regulatory statues while considering both the facility's maternal level of care and available resources. This review examines the history of the development of obstetric triage, current considerations in a contemporary obstetric triage paradigm, and future areas for consideration. An example of a contemporary obstetric triage program at an academic medical center is presented. A successful contemporary obstetric triage paradigm is one that addresses the questions of "sick or not sick" and "labor or no labor," for every obstetric patient that presents for care. Failure to do so risks poor patient outcome, poor patient satisfaction, adverse litigation outcome, regulatory scrutiny, and exclusion from federal payment programs. Understanding the role of contemporary obstetric triage in the current health care environment is important for both providers and health care leadership. This study is for obstetricians and gynecologists as well as family physicians. After completing this activity, the learner should be better able to understand the scope of a medical screening examination within the context of contemporary obstetric triage; understand how a facility's level of maternal care influences clinical decision making in a contemporary obstetric triage setting; and understand the considerations necessary for the systematic evaluation of the 2 basic contemporary obstetric questions, "sick or not sick?" and "labor or no labor?"
Ng, Chip-Jin; Hsu, Kuang-Hung; Kuan, Jen-Tze; Chiu, Te-Fa; Chen, Wei-Kong; Lin, Hung-Jung; Bullard, Michael J; Chen, Jih-Chang
2010-11-01
Since the implementation of National Health Insurance in Taiwan, Emergency Department (ED) volume has progressively increased, and the current triage system is insufficient and needs modification. This study compared the prioritization and resource utilization differences between the four-level Taiwan Triage System (TTS) and the standardized five-level Canadian Triage and Acuity Scale (CTAS) among ED patients. This was a prospective observational study. All adult ED patients who presented to three different medical centers during the study period were included. Patients were independently triaged by the duty triage nurse using TTS, and a single trained research nurse using CTAS with a computer support software system. Hospitalization, length of stay (LOS), and medical resource consumption were analyzed by comparing TTS and CTAS by acuity levels. There was significant disparity in patient prioritization between TTS and CTAS among the 1851 enrolled patients. With TTS, 7.8%, 46.1%, 45.9% and 0.2% were assigned to levels 1, 2, 3, and 4, respectively. With CTAS, 3.5%, 24.4%, 44.3%, 22.4% and 5.5% were assigned to levels 1, 2, 3, 4, and 5, respectively. The hospitalization rate, LOS, and medical resource consumption differed significantly between the two triage systems and correlated better with CTAS. CTAS provided better discrimination for ED patient triage, and also showed greater validity when predicting hospitalization, LOS, and medical resource consumption. An accurate five-level triage scale appeared superior in predicting patient acuity and resource utilization. Copyright © 2010 Formosan Medical Association & Elsevier. Published by Elsevier B.V. All rights reserved.
Iravani, Amir; Hofman, Michael S; Mulcahy, Tony; Williams, Scott; Murphy, Declan; Parameswaran, Bimal K; Hicks, Rodney J
2017-12-21
68 Ga-labelled prostate specific membrane antigen (PSMA) ligand PET/CT is a promising modality in primary staging (PS) and biochemical relapse (BCR) of prostate cancer (PC). However, pelvic nodes or local recurrences can be difficult to differentiate from radioactive urine. CT urography (CT-U) is an established method, which allows assessment of urological malignancies. The study presents a novel protocol of 68 Ga-PSMA-11 PET/CT-U in PS and BCR of PC. A retrospective review of PSMA PET/CT-U preformed on 57 consecutive patients with prostate cancer. Fifty mL of IV contrast was administered 10 min (range 8-15) before the CT component of a combined PET/CT study, acquired approximately 60 min (range 40-85) after administration of 166 MBq (range 91-246) of 68 Ga-PSMA-11. PET and PET/CT-U were reviewed by two nuclear medicine physicians and CT-U by a radiologist. First, PET images were reviewed independently followed by PET/CT-U images. Foci of activity which could not unequivocally be assessed as disease or urinary activity were recorded. PET/CT-U was considered of potential benefit in final interpretation when the equivocal focal activity in PET images corresponded to opacified ureter, bladder, prostate bed, seminal vesicles, or urethra. Student's T test and Pearson's correlation coefficient was used for assessment of variables including lymph node size and standardized uptake value. Overall 50 PSMA PET/CT-U studies were performed for BCR and 7 for PS. Median PSA with BCR and PS were 2.0 ± 11.4 ng/ml (0.06-57.3 ng/ml) and 18 ± 35.3 ng/ml (6.8-100 ng/ml), respectively. The median Gleason-score for both groups was 7 (range 6-10). In BCR group, PSMA PET was reported positive in 36 (72%) patients, CT-U in 11(22%) patients and PET/CT-U in 33 (66%) patients. In PS group, PSMA PET detected the primary site in all seven patients, of which one patient with metastatic nodal disease had negative CT finding. Of 40 equivocal foci (27/57 patients) on PET, 11 foci (10/57 patients, 17.5%) were localized to enhanced urine on PET/CT-U, hence considered of potential benefit in interpretation. Of those, 3 foci (3 patients) were solitary sites of activity on PSMA imaging including two local and one nodal site and 4 foci (3 patients) were in different nodal fields. PET/CT-U protocol is a practical approach and may assist in interpretation of 68 Ga-PSMA-11 imaging by delineation of the contrast opacified genitourinary system and matching focal PSMA activity with urinary contrast.
[How to implement a unique triage system in the emergency departments of Latium, Italy].
De Luca, A; Francia, C; Gabriele, S; Guasticchi, G
2008-01-01
Triage is an efficient system that emergency departments (EDs) use to sort out presenting patients on the basis of the speed with which they need treatment. Because triage is not used consistently in the EDs of Latium, a region in central Italy, the regional Public Health Agency (PHA) planned and implemented a regional model of triage in all EDs. This manuscript describe the regional implementation strategy. The PHA activated the "Regional Triage Program--RTP" including: development and testing of a "triage section" in the computerized EDs clinical chart; production of an operational handbook for the RTP for triage health professionals (HPs); implementation of an continuum educational program on the "RTP" in all EDs of Latium. The computerized triage section was tested and implemented in all EDs in the region. The handbook for triage HPs was produced. The educational program, has been ongoing since 2008 in all regional EDs. Selected HPs, identified as "facilitators", were trained on how to implement the RTP. They will organize, in their own EDs, small groups of nurses to conduct on-site training of the RTP. The RTP was received with enthusiasm by most HPs, however its introduction into current practice could be hampered by organizational/structural problems and conflicts between nurses and doctors. Next actions of the regional program will be to overcome the possible above mentioned troubles.
Lansdowne, Krystal; Scully, Christopher G; Galeotti, Loriano; Schwartz, Suzanne; Marcozzi, David; Strauss, David G
2015-06-01
In 2010, the US Food and Drug Administration (Silver Spring, Maryland USA) created the Medical Countermeasures Initiative with the mission of development and promoting medical countermeasures that would be needed to protect the nation from identified, high-priority chemical, biological, radiological, or nuclear (CBRN) threats and emerging infectious diseases. The aim of this review was to promote regulatory science research of medical devices and to analyze how the devices can be employed in different CBRN scenarios. Triage in CBRN scenarios presents unique challenges for first responders because the effects of CBRN agents and the clinical presentations of casualties at each triage stage can vary. The uniqueness of a CBRN event can render standard patient monitoring medical device and conventional triage algorithms ineffective. Despite the challenges, there have been recent advances in CBRN triage technology that include: novel technologies; mobile medical applications ("medical apps") for CBRN disasters; electronic triage tags, such as eTriage; diagnostic field devices, such as the Joint Biological Agent Identification System; and decision support systems, such as the Chemical Hazards Emergency Medical Management Intelligent Syndromes Tool (CHEMM-IST). Further research and medical device validation can help to advance prehospital triage technology for CBRN events.
An exploration of clinical decision making in mental health triage.
Sands, Natisha
2009-08-01
Mental health (MH) triage is a specialist area of clinical nursing practice that involves complex decision making. The discussion in this article draws on the findings of a Ph.D. study that involved a statewide investigation of the scope of MH triage nursing practice in Victoria, Australia. Although the original Ph.D. study investigated a number of core practices in MH triage, the focus of the discussion in this article is specifically on the findings related to clinical decision making in MH triage, which have not previously been published. The study employed an exploratory descriptive research design that used mixed data collection methods including a survey questionnaire (n = 139) and semistructured interviews (n = 21). The study findings related to decision making revealed a lack of empirically tested evidence-based decision-making frameworks currently in use to support MH triage nursing practice. MH triage clinicians in Australia rely heavily on clinical experience to underpin decision making and have little of knowledge of theoretical models for practice, such as methodologies for rating urgency. A key recommendation arising from the study is the need to develop evidence-based decision-making frameworks such as clinical guidelines to inform and support MH triage clinical decision making.
Falzone, E; Pasquier, P; Hoffmann, C; Barbier, O; Boutonnet, M; Salvadori, A; Jarrassier, A; Renner, J; Malgras, B; Mérat, S
2017-02-01
Triage, a medical term derived from the French word "trier", is the practical process of sorting casualties to rationally allocate limited resources. In combat settings with limited medical resources and long transportation times, triage is challenging since the objectives are to avoid overcrowding medical treatment facilities while saving a maximum of soldiers and to get as many of them back into action as possible. The new face of modern warfare, asymmetric and non-conventional, has led to the integrative evolution of triage into the theatre of operations. This article defines different triage scores and algorithms currently implemented in military settings. The discrepancies associated with these military triage systems are highlighted. The assessment of combat casualty severity requires several scores and each nation adopts different systems for triage on the battlefield with the same aim of quickly identifying those combat casualties requiring lifesaving and damage control resuscitation procedures. Other areas of interest for triage in military settings are discussed, including predicting the need for massive transfusion, haemodynamic parameters and ultrasound exploration. Copyright © 2016 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.
Emerging technologies for pediatric and adult trauma care.
Moulton, Steven L; Haley-Andrews, Stephanie; Mulligan, Jane
2010-06-01
Current Emergency Medical Service protocols rely on provider-directed care for evaluation, management and triage of injured patients from the field to a trauma center. New methods to quickly diagnose, support and coordinate the movement of trauma patients from the field to the most appropriate trauma center are in development. These methods will enhance trauma care and promote trauma system development. Recent advances in machine learning, statistical methods, device integration and wireless communication are giving rise to new methods for vital sign data analysis and a new generation of transport monitors. These monitors will collect and synchronize exponentially growing amounts of vital sign data with electronic patient care information. The application of advanced statistical methods to these complex clinical data sets has the potential to reveal many important physiological relationships and treatment effects. Several emerging technologies are converging to yield a new generation of smart sensors and tightly integrated transport monitors. These technologies will assist prehospital providers in quickly identifying and triaging the most severely injured children and adults to the most appropriate trauma centers. They will enable the development of real-time clinical support systems of increasing complexity, able to provide timelier, more cost-effective, autonomous care.
Ramesh, Aruna C.; Kumar, S.
2010-01-01
In a mass casualty situation due to chemical, biological, radiological, or nuclear (CBRN) event, triage is absolutely required for categorizing the casualties in accordance with medical care priorities. Dealing with a CBRN event always starts at the local level. Even before the detection and analysis of agents can be undertaken, zoning, triage, decontamination, and treatment should be initiated promptly. While applying the triage system, the available medical resources and maximal utilization of medical assets should be taken into consideration by experienced triage officers who are most familiar with the natural course of the injury presented and have detailed information on medical assets. There are several triage systems that can be applied to CBRN casualties. With no one standardized system globally or nationally available, it is important for deploying a triage and decontamination system which is easy to follow and flexible to the available medical resources, casualty number, and severity of injury. PMID:21829319
NASA Astrophysics Data System (ADS)
Rui, Xue; Cheng, Lishui; Long, Yong; Fu, Lin; Alessio, Adam M.; Asma, Evren; Kinahan, Paul E.; De Man, Bruno
2015-09-01
For PET/CT systems, PET image reconstruction requires corresponding CT images for anatomical localization and attenuation correction. In the case of PET respiratory gating, multiple gated CT scans can offer phase-matched attenuation and motion correction, at the expense of increased radiation dose. We aim to minimize the dose of the CT scan, while preserving adequate image quality for the purpose of PET attenuation correction by introducing sparse view CT data acquisition. We investigated sparse view CT acquisition protocols resulting in ultra-low dose CT scans designed for PET attenuation correction. We analyzed the tradeoffs between the number of views and the integrated tube current per view for a given dose using CT and PET simulations of a 3D NCAT phantom with lesions inserted into liver and lung. We simulated seven CT acquisition protocols with {984, 328, 123, 41, 24, 12, 8} views per rotation at a gantry speed of 0.35 s. One standard dose and four ultra-low dose levels, namely, 0.35 mAs, 0.175 mAs, 0.0875 mAs, and 0.043 75 mAs, were investigated. Both the analytical Feldkamp, Davis and Kress (FDK) algorithm and the Model Based Iterative Reconstruction (MBIR) algorithm were used for CT image reconstruction. We also evaluated the impact of sinogram interpolation to estimate the missing projection measurements due to sparse view data acquisition. For MBIR, we used a penalized weighted least squares (PWLS) cost function with an approximate total-variation (TV) regularizing penalty function. We compared a tube pulsing mode and a continuous exposure mode for sparse view data acquisition. Global PET ensemble root-mean-squares-error (RMSE) and local ensemble lesion activity error were used as quantitative evaluation metrics for PET image quality. With sparse view sampling, it is possible to greatly reduce the CT scan dose when it is primarily used for PET attenuation correction with little or no measureable effect on the PET image. For the four ultra-low dose levels simulated, sparse view protocols with 41 and 24 views best balanced the tradeoff between electronic noise and aliasing artifacts. In terms of lesion activity error and ensemble RMSE of the PET images, these two protocols, when combined with MBIR, are able to provide results that are comparable to the baseline full dose CT scan. View interpolation significantly improves the performance of FDK reconstruction but was not necessary for MBIR. With the more technically feasible continuous exposure data acquisition, the CT images show an increase in azimuthal blur compared to tube pulsing. However, this blurring generally does not have a measureable impact on PET reconstructed images. Our simulations demonstrated that ultra-low-dose CT-based attenuation correction can be achieved at dose levels on the order of 0.044 mAs with little impact on PET image quality. Highly sparse 41- or 24- view ultra-low dose CT scans are feasible for PET attenuation correction, providing the best tradeoff between electronic noise and view aliasing artifacts. The continuous exposure acquisition mode could potentially be implemented in current commercially available scanners, thus enabling sparse view data acquisition without requiring x-ray tubes capable of operating in a pulsing mode.
Rui, Xue; Cheng, Lishui; Long, Yong; Fu, Lin; Alessio, Adam M.; Asma, Evren; Kinahan, Paul E.; De Man, Bruno
2015-01-01
For PET/CT systems, PET image reconstruction requires corresponding CT images for anatomical localization and attenuation correction. In the case of PET respiratory gating, multiple gated CT scans can offer phase-matched attenuation and motion correction, at the expense of increased radiation dose. We aim to minimize the dose of the CT scan, while preserving adequate image quality for the purpose of PET attenuation correction by introducing sparse view CT data acquisition. Methods We investigated sparse view CT acquisition protocols resulting in ultra-low dose CT scans designed for PET attenuation correction. We analyzed the tradeoffs between the number of views and the integrated tube current per view for a given dose using CT and PET simulations of a 3D NCAT phantom with lesions inserted into liver and lung. We simulated seven CT acquisition protocols with {984, 328, 123, 41, 24, 12, 8} views per rotation at a gantry speed of 0.35 seconds. One standard dose and four ultra-low dose levels, namely, 0.35 mAs, 0.175 mAs, 0.0875 mAs, and 0.04375 mAs, were investigated. Both the analytical FDK algorithm and the Model Based Iterative Reconstruction (MBIR) algorithm were used for CT image reconstruction. We also evaluated the impact of sinogram interpolation to estimate the missing projection measurements due to sparse view data acquisition. For MBIR, we used a penalized weighted least squares (PWLS) cost function with an approximate total-variation (TV) regularizing penalty function. We compared a tube pulsing mode and a continuous exposure mode for sparse view data acquisition. Global PET ensemble root-mean-squares-error (RMSE) and local ensemble lesion activity error were used as quantitative evaluation metrics for PET image quality. Results With sparse view sampling, it is possible to greatly reduce the CT scan dose when it is primarily used for PET attenuation correction with little or no measureable effect on the PET image. For the four ultra-low dose levels simulated, sparse view protocols with 41 and 24 views best balanced the tradeoff between electronic noise and aliasing artifacts. In terms of lesion activity error and ensemble RMSE of the PET images, these two protocols, when combined with MBIR, are able to provide results that are comparable to the baseline full dose CT scan. View interpolation significantly improves the performance of FDK reconstruction but was not necessary for MBIR. With the more technically feasible continuous exposure data acquisition, the CT images show an increase in azimuthal blur compared to tube pulsing. However, this blurring generally does not have a measureable impact on PET reconstructed images. Conclusions Our simulations demonstrated that ultra-low-dose CT-based attenuation correction can be achieved at dose levels on the order of 0.044 mAs with little impact on PET image quality. Highly sparse 41- or 24- view ultra-low dose CT scans are feasible for PET attenuation correction, providing the best tradeoff between electronic noise and view aliasing artifacts. The continuous exposure acquisition mode could potentially be implemented in current commercially available scanners, thus enabling sparse view data acquisition without requiring x-ray tubes capable of operating in a pulsing mode. PMID:26352168
Kim, Chang Rae; Jeon, Ji Young
2018-05-01
The purpose of this article is to compare radiation doses and conspicuity of anatomic landmarks of the temporal bone between the CT technique using spectral beam shaping at 150 kVp with a dedicated tin filter (150 kVp-Sn) and the conventional protocol at 120 kVp. 25 patients (mean age, 46.8 ± 21.2 years) were examined using the 150-kVp Sn protocol (200 reference mAs using automated tube current modulation, 64 × 0.6 mm collimation, 0.6 mm slice thickness, pitch 0.8), whereas 30 patients (mean age, 54.5 ± 17.8 years) underwent the 120-kVp protocol (180 mAs, 128 × 0.6 mm collimation, 0.6 mm slice thickness, pitch 0.8). Radiation doses were compared between the two acquisition techniques, and dosimetric data from the literature were reviewed for comparison of radiation dose reduction. Subjective conspicuity of 23 anatomic landmarks of the temporal bone, expressed by 5-point rating scale and objective conspicuity by signal-to-noise ratio (SNR) which measured in 4 different regions of interest (ROI), were compared between 150-kVp Sn and 120-kVp acquisitions. The mean dose-length-product (DLP) and effective dose were significantly lower for the 150-kVp Sn scans (0.26 ± 0.26 mSv) compared with the 120-kVp scans (0.92 ± 0.10 mSv, p < 0.001). The lowest effective dose from the literature-based protocols was 0.31 ± 0.12 mSv, which proposed as a low-dose protocol in the setting of spiral multislice temporal bone CT. SNR was slightly superior for 120-kVp images, however analyzability of the 23 anatomic structures did not differ significantly between 150-kVp Sn and 120-kVp scans. Temporal bone CT performed at 150 kVp with an additional tin filter for spectral shaping markedly reduced radiation exposure when compared with conventional temporal bone CT at 120 kVp while maintaining anatomic conspicuity. The decreased radiation dose of the 150-kVp Sn was also lower in comparison to the previous literature-based low-dose temporal bone CT protocol. Copyright © 2018 Elsevier B.V. All rights reserved.
Wardlaw, Joanna; Brazzelli, Miriam; Miranda, Hector; Chappell, Francesca; McNamee, Paul; Scotland, Graham; Quayyum, Zahid; Martin, Duncan; Shuler, Kirsten; Sandercock, Peter; Dennis, Martin
2014-04-01
Patients with transient ischaemic attack (TIA) or minor stroke need rapid treatment of risk factors to prevent recurrent stroke. ABCD2 score or magnetic resonance diffusion-weighted brain imaging (MR DWI) may help assessment and treatment. Is MR with DWI cost-effective in stroke prevention compared with computed tomography (CT) brain scanning in all patients, in specific subgroups or as 'one-stop' brain-carotid imaging? What is the current UK availability of services for stroke prevention? Published literature; stroke registries, audit and randomised clinical trials; national databases; survey of UK clinical and imaging services for stroke; expert opinion. Systematic reviews and meta-analyses of published/unpublished data. Decision-analytic model of stroke prevention including on a 20-year time horizon including nine representative imaging scenarios. The pooled recurrent stroke rate after TIA (53 studies, 30,558 patients) is 5.2% [95% confidence interval (CI) 3.9% to 5.9%] by 7 days, and 6.7% (5.2% to 8.7%) at 90 days. ABCD2 score does not identify patients with key stroke causes or identify mimics: 66% of specialist-diagnosed true TIAs and 35-41% of mimics had an ABCD2 score of ≥ 4; 20% of true TIAs with ABCD2 score of < 4 had key risk factors. MR DWI (45 studies, 9078 patients) showed an acute ischaemic lesion in 34.3% (95% CI 30.5% to 38.4%) of TIA, 69% of minor stroke patients, i.e. two-thirds of TIA patients are DWI negative. TIA mimics (16 studies, 14,542 patients) make up 40-45% of patients attending clinics. UK survey (45% response) showed most secondary prevention started prior to clinic, 85% of primary brain imaging was same-day CT; 51-54% of patients had MR, mostly additional to CT, on average 1 week later; 55% omitted blood-sensitive MR sequences. Compared with 'CT scan all patients' MR was more expensive and no more cost-effective, except for patients presenting at > 1 week after symptoms to diagnose haemorrhage; strategies that triaged patients with low ABCD2 scores for slow investigation or treated DWI-negative patients as non-TIA/minor stroke prevented fewer strokes and increased costs. 'One-stop' CT/MR angiographic-plus-brain imaging was not cost-effective. Data on sensitivity/specificity of MR in TIA/minor stroke, stroke costs, prognosis of TIA mimics and accuracy of ABCD2 score by non-specialists are sparse or absent; all analysis had substantial heterogeneity. Magnetic resonance with DWI is not cost-effective for secondary stroke prevention. MR was most helpful in patients presenting at > 1 week after symptoms if blood-sensitive sequences were used. ABCD2 score is unlikely to facilitate patient triage by non-stroke specialists. Rapid specialist assessment, CT brain scanning and identification of serious underlying stroke causes is the most cost-effective stroke prevention strategy. The National Institute for Health Research Health Technology Assessment programme.
Lee, James S; Franc, Jeffrey M
2015-08-01
A high influx of patients during a mass-casualty incident (MCI) may disrupt patient flow in an already overcrowded emergency department (ED) that is functioning beyond its operating capacity. This pilot study examined the impact of a two-step ED triage model using Simple Triage and Rapid Treatment (START) for pre-triage, followed by triage with the Canadian Triage and Acuity Scale (CTAS), on patient flow during a MCI simulation exercise. Hypothesis/Problem It was hypothesized that there would be no difference in time intervals nor patient volumes at each patient-flow milestone. Physicians and nurses participated in a computer-based tabletop disaster simulation exercise. Physicians were randomized into the intervention group using START, then CTAS, or the control group using START alone. Patient-flow milestones including time intervals and patient volumes from ED arrival to triage, ED arrival to bed assignment, ED arrival to physician assessment, and ED arrival to disposition decision were compared. Triage accuracy was compared for secondary purposes. There were no significant differences in the time interval from ED arrival to triage (mean difference 108 seconds; 95% CI, -353 to 596 seconds; P=1.0), ED arrival to bed assignment (mean difference 362 seconds; 95% CI, -1,269 to 545 seconds; P=1.0), ED arrival to physician assessment (mean difference 31 seconds; 95% CI, -1,104 to 348 seconds; P=0.92), and ED arrival to disposition decision (mean difference 175 seconds; 95% CI, -1,650 to 1,300 seconds; P=1.0) between the two groups. There were no significant differences in the volume of patients to be triaged (32% vs 34%; 95% CI for the difference -16% to 21%; P=1.0), assigned a bed (16% vs 21%; 95% CI for the difference -11% to 20%; P=1.0), assessed by a physician (20% vs 22%; 95% CI for the difference -14% to 19%; P=1.0), and with a disposition decision (20% vs 9%; 95% CI for the difference -25% to 4%; P=.34) between the two groups. The accuracy of triage was similar in both groups (57% vs 70%; 95% CI for the difference -15% to 41%; P=.46). Experienced triage nurses were able to apply CTAS effectively during a MCI simulation exercise. A two-step ED triage model using START, then CTAS, had similar patient flow and triage accuracy when compared to START alone.
Horspool, Kimberley; Drabble, Sarah J; O'Cathain, Alicia
2016-09-07
Street Triage is a collaborative service between mental health workers and police which aims to improve the emergency response to individuals experiencing crisis, but peer reviewed evidence of the effectiveness of these services is limited. We examined the design and potential impact of two services, along with factors that hindered and facilitated the implementation of the services. We conducted 14 semi-structured interviews with mental health and police stakeholders with experience of a Street Triage service in two locations of the UK. Framework analysis identified themes related to key aspects of the Street Triage service, perceived benefits of Street Triage, and ways in which the service could be developed in the future. Stakeholders endorsed the Street Triage services which utilised different operating models. These models had several components including a joint response vehicle or a mental health worker in a police control room. Operating models were developed with consideration of the local geographical and population density. The ability to make referrals to the existing mental health service was perceived as key to the success of the service yet there was evidence to suggest Street Triage had the potential to increase pressure on already stretched mental health and police services. Identifying staff with skills and experience for Street Triage work was important, and their joint response resulted in shared decision making which was less risk averse for the police and regarded as in the interest of patient care by mental health professionals. Collaboration during Street Triage improved the understanding of roles and responsibilities in the 'other' agency and led to the development of local information sharing agreements. Views about the future direction of the service focused on expansion of Street Triage to address other shared priorities such as frequent users of police and mental health services, and a reduction in the police involvement in crisis response. The Street Triage service received strong support from stakeholders involved in it. Referral to existing health services is a key function of Street Triage, and its impact on referral behaviour requires rigorous evaluation. Street Triage may result in improvement to collaborative working but competing demands for resources within mental health and police services presented challenges for implementation.
Varley, Anna; Warren, Fiona C.; Richards, Suzanne H.; Calitri, Raff; Chaplin, Katherine; Fletcher, Emily; Holt, Tim A.; Lattimer, Valerie; Murdoch, Jamie; Richards, David A.; Campbell, John
2016-01-01
Background Nurse-led telephone triage is increasingly used to manage demand for general practitioner consultations in UK general practice. Previous studies are equivocal about the relationship between clinical experience and the call outcomes of nurse triage. Most research is limited to investigating nurse telephone triage in out-of-hours settings. Objective To investigate whether the professional characteristics of primary care nurses undertaking computer decision supported software telephone triage are related to call disposition. Design Questionnaire survey of nurses delivering the nurse intervention arm of the ESTEEM trial, to capture role type (practice nurse or nurse practitioner), prescriber status, number of years’ nursing experience, graduate status, previous experience of triage, and perceived preparedness for triage. Our main outcome was the proportion of triaged patients recommended for follow-up within the practice (call disposition), including all contact types (face-to-face, telephone or home visit), by a general practitioner or nurse. Settings 15 general practices and 7012 patients receiving the nurse triage intervention in four regions of the UK. Participants 45 nurse practitioners and practice nurse trained in the use of clinical decision support software. Methods We investigated the associations between nursing characteristics and triage call disposition for patient ‘same-day’ appointment requests in general practice using multivariable logistic regression modelling. Results Valid responses from 35 nurses (78%) from 14 practices: 31/35 (89%) had ≥10 years’ experience with 24/35 (69%) having ≥20 years. Most patient contacts (3842/4605; 86%) were recommended for follow-up within the practice. Nurse practitioners were less likely to recommend patients for follow-up odds ratio 0.19, 95% confidence interval 0.07; 0.49 than practice nurses. Nurses who reported that their previous experience had prepared them less well for triage were more likely to recommend patients for follow-up (OR 3.17, 95% CI 1.18–5.55). Conclusion Nurse characteristics were associated with disposition of triage calls to within practice follow-up. Nurse practitioners or those who reported feeling ‘more prepared’ for the role were more likely to manage the call definitively. Practices considering nurse triage should ensure that nurses transitioning into new roles feel adequately prepared. While standardised training is necessary, it may not be sufficient to ensure successful implementation. PMID:27087294
A time-motion study of ambulance-to-emergency department radio communications.
Penner, Mark S; Cone, David C; MacMillan, Don
2003-01-01
A prospective time-motion study of radio communication between inbound ambulances and emergency department (ED) triage personnel was conducted to assess hospital triage staff time utilized, and how often radio reports result in actions taken in the ED to prepare for patient arrival. The study hypothesis was that reports for "priority 2" (P2, nonemergent) patients rarely provide information that is acted upon in the ED prior to the patient's arrival. The study was conducted at an academic adult ED receiving 22,000 ambulances per year. An observer in the ED monitored and timed (to the second) all radio reports as well as the activities of triage nurses and arriving emergency medical services (EMS) personnel. A convenience sample of 437 reports was collected: 83 priority 1 (P1, emergent) and 354 P2. Average report times (minutes:seconds) with ranges were 0:53 (0:07-1:57) for P1, and 0:44 (0:04-3:50) for P2. Only 16% of the P2 reports resulted in any preparatory action, and 55% of these were requests to have hospital police officers available to receive intoxicated patients, as per local protocol. An in-person report was given in the ED for 61% of the P2 cases, and in 48% of these, the in-person report was longer than the radio report. In the system studied, P2 reports rarely provide information that is acted on prior to the patient's arrival. The time spent giving a radio report is frequently duplicated in the ED. Radio reports for low-priority patients may not be an efficient or productive use of providers' or nurses' time.
Accuracy and Efficiency of Orthoptists in Comprehensive Pediatric Eye Examinations.
Scheetz, Jane; Koklanis, Konstandina; Long, Maureen; Morris, Meg E
2016-01-01
To investigate the level of agreement between orthoptists and medical practitioners in the comprehensive eye examination of children seen in an orthoptist-led triage clinic. Patient records over a 6-month period were retrospectively reviewed. Those with a presenting complaint related to vision or ocular motility were triaged into the orthoptist-led clinic and included in the study. Patients who did not meet the triage protocol and those who were not assessed by a medical practitioner at a subsequent appointment were excluded from analysis. The clinical findings from the orthoptist and medical practitioner were collected and compared. In total, sixty-three patients were reviewed during the 6-month period and met the inclusion criteria. After the initial comprehensive eye examination with an orthoptist, thirty-two were discharged from hospital and thirty-one were asked to return for a review appointment with a medical practitioner. Agreement between the orthoptists and medical practitioners for the diagnosis of strabismus and/or amblyopia was 84.6% (κ = 0.649, P < 0.001). There was strong agreement between orthoptists and medical practitioners for refractive error of the right eye [τ (19) = 0.352, P = 0.729] and left eye [τ (19) = 1.785, P = 0.090]. Fundus examination comparisons between the orthoptists and medical practitioners showed very high agreement (95.7%). Orthoptists have the skills necessary to provide comprehensive care of children referred for ocular motility and/or vision related disorders. There was close agreement between orthoptists and medical practitioners when performing comprehensive eye examinations. © 2016 Board of regents of the University of Wisconsin System, American Orthoptic Journal, Volume 66, 2016, ISSN 0065-955X, E-ISSN 1553-4448.
Price, C L; Brace-McDonnell, S J; Stallard, N; Bleetman, A; Maconochie, I; Perkins, G D
2016-05-01
Context Triage tools are an essential component of the emergency response to a major incident. Although fortunately rare, mass casualty incidents involving children are possible which mandate reliable triage tools to determine the priority of treatment. To determine the performance characteristics of five major incident triage tools amongst paediatric casualties who have sustained traumatic injuries. Retrospective observational cohort study using data from 31,292 patients aged less than 16 years who sustained a traumatic injury. Data were obtained from the UK Trauma Audit and Research Network (TARN) database. Interventions Statistical evaluation of five triage tools (JumpSTART, START, CareFlight, Paediatric Triage Tape/Sieve and Triage Sort) to predict death or severe traumatic injury (injury severity score >15). Main outcome measures Performance characteristics of triage tools (sensitivity, specificity and level of agreement between triage tools) to identify patients at high risk of death or severe injury. Of the 31,292 cases, 1029 died (3.3%), 6842 (21.9%) had major trauma (defined by an injury severity score >15) and 14,711 (47%) were aged 8 years or younger. There was variation in the performance accuracy of the tools to predict major trauma or death (sensitivities ranging between 36.4 and 96.2%; specificities 66.0-89.8%). Performance characteristics varied with the age of the child. CareFlight had the best overall performance at predicting death, with the following sensitivity and specificity (95% CI) respectively: 95.3% (93.8-96.8) and 80.4% (80.0-80.9). JumpSTART was superior for the triaging of children under 8 years; sensitivity and specificity (95% CI) respectively: 86.3% (83.1-89.5) and 84.8% (84.2-85.5). The triage tools were generally better at identifying patients who would die than those with non-fatal severe injury. This statistical evaluation has demonstrated variability in the accuracy of triage tools at predicting outcomes for children who sustain traumatic injuries. No single tool performed consistently well across all evaluated scenarios. Copyright © 2015 Elsevier Ltd. All rights reserved.
Green, Esther; Ballantyne, Barbara; Tarasuk, Joy; Skrutkowski, Myriam; Carley, Meg; Chapman, Kim; Kuziemsky, Craig; Kolari, Erin; Sabo, Brenda; Saucier, Andréanne; Shaw, Tara; Tardif, Lucie; Truant, Tracy; Cummings, Greta G.; Howell, Doris
2016-01-01
ABSTRACT Background The pan‐Canadian Oncology Symptom Triage and Remote Support (COSTaRS) team developed 13 evidence‐informed protocols for symptom management. Aim To build an effective and sustainable approach for implementing the COSTaRS protocols for nurses providing telephone‐based symptom support to cancer patients. Methods A comparative case study was guided by the Knowledge to Action Framework. Three cases were created for three Canadian oncology programs that have nurses providing telephone support. Teams of researchers and knowledge users: (a) assessed barriers and facilitators influencing protocol use, (b) adapted protocols for local use, (c) intervened to address barriers, (d) monitored use, and (e) assessed barriers and facilitators influencing sustained use. Analysis was within and across cases. Results At baseline, >85% nurses rated protocols positively but barriers were identified (64‐80% needed training). Patients and families identified similar barriers and thought protocols would enhance consistency among nurses teaching self‐management. Twenty‐two COSTaRS workshops reached 85% to 97% of targeted nurses (N = 119). Nurses felt more confident with symptom management and using the COSTaRS protocols (p < .01). Protocol adaptations addressed barriers (e.g., health records approval, creating pocket versions, distributing with telephone messages). Chart audits revealed that protocols used were documented for 11% to 47% of patient calls. Sustained use requires organizational alignment and ongoing leadership support. Linking Evidence to Action Protocol uptake was similar to trials that have evaluated tailored interventions to improve professional practice by overcoming identified barriers. Collaborating with knowledge users facilitated interpretation of findings, aided protocol adaptation, and supported implementation. Protocol implementation in nursing requires a tailored approach. A multifaceted intervention approach increased nurses’ use of evidence‐informed protocols during telephone calls with patients about symptoms. Training and other interventions improved nurses’ confidence with using COSTaRS protocols and their uptake was evident in some documented telephone calls. Protocols could be adapted for use by patients and nurses globally. PMID:27243574
Five-level emergency triage systems: variation in assessment of validity.
Kuriyama, Akira; Urushidani, Seigo; Nakayama, Takeo
2017-11-01
Triage systems are scales developed to rate the degree of urgency among patients who arrive at EDs. A number of different scales are in use; however, the way in which they have been validated is inconsistent. Also, it is difficult to define a surrogate that accurately predicts urgency. This systematic review described reference standards and measures used in previous validation studies of five-level triage systems. We searched PubMed, EMBASE and CINAHL to identify studies that had assessed the validity of five-level triage systems and described the reference standards and measures applied in these studies. Studies were divided into those using criterion validity (reference standards developed by expert panels or triage systems already in use) and those using construct validity (prognosis, costs and resource use). A total of 57 studies examined criterion and construct validity of 14 five-level triage systems. Criterion validity was examined by evaluating (1) agreement between the assigned degree of urgency with objective standard criteria (12 studies), (2) overtriage and undertriage (9 studies) and (3) sensitivity and specificity of triage systems (7 studies). Construct validity was examined by looking at (4) the associations between the assigned degree of urgency and measures gauged in EDs (48 studies) and (5) the associations between the assigned degree of urgency and measures gauged after hospitalisation (13 studies). Particularly, among 46 validation studies of the most commonly used triages (Canadian Triage and Acuity Scale, Emergency Severity Index and Manchester Triage System), 13 and 39 studies examined criterion and construct validity, respectively. Previous studies applied various reference standards and measures to validate five-level triage systems. They either created their own reference standard or used a combination of severity/resource measures. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lewis, Lorraine; Cox, Jennifer; Faculty of Health Sciences, University of Sydney, Sydney, New South Wales
2015-09-15
The clinical target volume (CTV) for early stage breast cancer is difficult to clearly identify on planning computed tomography (CT) scans. Surgical clips inserted around the tumour bed should help to identify the CTV, particularly if the seroma has been reabsorbed, and enable tracking of CTV changes over time. A surgical clip-based CTV delineation protocol was introduced. CTV visibility and its post-operative shrinkage pattern were assessed. The subjects were 27 early stage breast cancer patients receiving post-operative radiotherapy alone and 15 receiving post-operative chemotherapy followed by radiotherapy. The radiotherapy alone (RT/alone) group received a CT scan at median 25 daysmore » post-operatively (CT1rt) and another at 40 Gy, median 68 days (CT2rt). The chemotherapy/RT group (chemo/RT) received a CT scan at median 18 days post-operatively (CT1ch), a planning CT scan at median 126 days (CT2ch), and another at 40 Gy (CT3ch). There was no significant difference (P = 0.08) between the initial mean CTV for each cohort. The RT/alone cohort showed significant CTV volume reduction of 38.4% (P = 0.01) at 40 Gy. The Chemo/RT cohort had significantly reduced volumes between CT1ch: median 54 cm{sup 3} (4–118) and CT2ch: median 16 cm{sup 3}, (2–99), (P = 0.01), but no significant volume reduction thereafter. Surgical clips enable localisation of the post-surgical seroma for radiotherapy targeting. Most seroma shrinkage occurs early, enabling CT treatment planning to take place at 7 weeks, which is within the 9 weeks recommended to limit disease recurrence.« less
Haneder, Stefan; Siedek, Florian; Doerner, Jonas; Pahn, Gregor; Grosse Hokamp, Nils; Maintz, David; Wybranski, Christian
2018-01-01
Background A novel, multi-energy, dual-layer spectral detector computed tomography (SDCT) is commercially available now with the vendor's claim that it yields the same or better quality of polychromatic, conventional CT images like modern single-energy CT scanners without any radiation dose penalty. Purpose To intra-individually compare the quality of conventional polychromatic CT images acquired with a dual-layer spectral detector (SDCT) and the latest generation 128-row single-energy-detector (CT128) from the same manufacturer. Material and Methods Fifty patients underwent portal-venous phase, thoracic-abdominal CT scans with the SDCT and prior CT128 imaging. The SDCT scanning protocol was adapted to yield a similar estimated dose length product (DLP) as the CT128. Patient dose optimization by automatic tube current modulation and CT image reconstruction with a state-of-the-art iterative algorithm were identical on both scanners. CT image contrast-to-noise ratio (CNR) was compared between the SDCT and CT128 in different anatomic structures. Image quality and noise were assessed independently by two readers with 5-point-Likert-scales. Volume CT dose index (CTDI vol ), and DLP were recorded and normalized to 68 cm acquisition length (DLP 68 ). Results The SDCT yielded higher mean CNR values of 30.0% ± 2.0% (26.4-32.5%) in all anatomic structures ( P < 0.001) and excellent scores for qualitative parameters surpassing the CT128 (all P < 0.0001) with substantial inter-rater agreement (κ ≥ 0.801). Despite adapted scan protocols the SDCT yielded lower values for CTDI vol (-10.1 ± 12.8%), DLP (-13.1 ± 13.9%), and DLP 68 (-15.3 ± 16.9%) than the CT128 (all P < 0.0001). Conclusion The SDCT scanner yielded better CT image quality compared to the CT128 and lower radiation dose parameters.
The role of advanced reconstruction algorithms in cardiac CT
Halliburton, Sandra S.; Tanabe, Yuki; Partovi, Sasan
2017-01-01
Non-linear iterative reconstruction (IR) algorithms have been increasingly incorporated into clinical cardiac CT protocols at institutions around the world. Multiple IR algorithms are available commercially from various vendors. IR algorithms decrease image noise and are primarily used to enable lower radiation dose protocols. IR can also be used to improve image quality for imaging of obese patients, coronary atherosclerotic plaques, coronary stents, and myocardial perfusion. In this article, we will review the various applications of IR algorithms in cardiac imaging and evaluate how they have changed practice. PMID:29255694
Decision analytic model exploring the cost and cost-offset implications of street triage
Heslin, Margaret; Callaghan, Lynne; Packwood, Martin; Badu, Vincent; Byford, Sarah
2016-01-01
Objectives To determine if street triage is effective at reducing the total number of people with mental health needs detained under section 136, and is associated with cost savings compared to usual police response. Design Routine data from a 6-month period in the year before and after the implementation of a street triage scheme were used to explore detentions under section 136, and to populate a decision analytic model to explore the impact of street triage on the cost to the NHS and the criminal justice sector of supporting people with a mental health need. Setting A predefined area of Sussex, South East England, UK. Participants All people who were detained under section 136 within the predefined area or had contact with the street triage team. Interventions The street triage model used here was based on a psychiatric nurse attending incidents with a police constable. Primary and secondary outcome measures The primary outcome was change in the total number of detentions under section 136 between the before and after periods assessed. Secondary analysis focused on whether the additional costs of street triage were offset by cost savings as a result of changes in detentions under section 136. Results Detentions under section 136 in the street triage period were significantly lower than in the usual response period (118 vs 194 incidents, respectively; χ2 (1df) 18.542, p<0.001). Total NHS and criminal justice costs were estimated to be £1043 in the street triage period compared to £1077 in the usual response period. Conclusions Investment in street triage was offset by savings as a result of reduced detentions under section 136, particularly detentions in custody. Data available did not include assessment of patient outcomes, so a full economic evaluation was not possible. PMID:26868943
Patient satisfaction with triage nursing care in Hong Kong.
Chan, Jaime Nga Han; Chau, Janita
2005-06-01
This paper reports a study to examine the relationship between patient satisfaction and triage nursing care in order to assist nurses in defining more clearly their roles, and ultimately to improve the quality of care delivered to emergency patients. Patient satisfaction is considered an important indicator of quality care from the perspective of the consumer and has been widely studied in many settings. However, few studies have examined patient satisfaction with emergency nursing services in the particular area of triage. A descriptive, correlational study was conducted in 2001 in one urban acute hospital in Hong Kong using Consumer Emergency Care Satisfaction Scale (CECSS), and patient and nurse demographic data were also collected. Following a power calculation, systematic sampling was carried out, and the final sample consisted of 56 urgent, semi-urgent and non-urgent patients triaged. The response rate was 61%. The majority of the participants were satisfied with their triage nursing care and teaching. However, difficulties were encountered during the data collection process, resulting in a relatively low response rate. Correlational analyses revealed that patient satisfaction with triage nursing care was statistically significantly correlated with age and the type of nursing intervention received. Older people were more satisfied with the teaching offered by triage nurses and patients who had received specific nursing interventions gave more positive ratings on the teaching subscale of the CECSS. There were no statistically significant relationships between patient satisfaction with triage nursing care and nurse characteristics, including gender, work experiences and educational level. Patients were generally satisfied with the care provided by the triage nurses. Measuring patient satisfaction with triage nursing care remains a major challenge for health care providers in emergency care settings.
The use of a kiosk-model bilingual self-triage system in the pediatric emergency department.
Sinha, Madhumita; Khor, Kai-Ning; Amresh, Ashish; Drachman, David; Frechette, Alan
2014-01-01
Streamlining the triage process is the key in improving emergency department (ED) workflow. Our objective was to determine if parents of pediatric ED patients in, low-literacy, inner-city hospital, who used the audio-assisted bilingual (English/Spanish) self-triage kiosk, were able to enter their child's medical history data using a touch screen panel with greater speed and accuracy than routine nurse-initiated triage. Parent/child dyads visiting the pediatric ED for nonurgent conditions (February to April 2012) were randomized prospectively to self-triage kiosk group (n = 200) and standard nurse triage group (n = 200). Both groups underwent routine nurse-initiated triage that included verbal elicitation of basic medical history and manual entry into patients' electronic medical records. The kiosk user was a parent in 88.5% of the cases, a patient (range, 11-17 years) in 9.5% of the cases, and a proxy user (sibling or friend) in 2% of the cases. Language choice for kiosk use was equally distributed (English vs Spanish, 50.5% vs 49.5%). The mean (SD) time to enter medical history data by the kiosk group was significantly shorter than the standard nurse triage group (94.38 [38.61] vs 126.72 [62.61] seconds; P < 0.001). Significant inverse relationship was observed between parent education level and kiosk usage time (r = -0.26; P < 0.001). The mean inaccuracies were significantly lower for kiosk group (P < 0.05) in areas of medical, medication and immunization histories, and total discrepancy score. Kiosk triage enabled users to enter basic medical triage history data quickly and accurately in an ED setting with future potential for its wider use in improving ED workflow efficiency.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tsalafoutas, Ioannis A.; Varsamidis, Athanasios; Thalassinou, Stella
Purpose: To investigate the utility of the nested polymethylacrylate (PMMA) phantom (which is available in many CT facilities for CTDI measurements), as a tool for the presentation and comparison of the ways that two different CT automatic exposure control (AEC) systems respond to a phantom when various scan parameters and AEC protocols are modified.Methods: By offsetting the two phantom's components (the head phantom and the body ring) half-way along their longitudinal axis, a phantom with three sections of different x-ray attenuation was created. Scan projection radiographs (SPRs) and helical scans of the three-section phantom were performed on a Toshiba Aquilionmore » 64 and a Philips Brilliance 64 CT scanners, with different scan parameter selections [scan direction, pitch factor, slice thickness, and reconstruction interval (ST/RI), AEC protocol, and tube potential used for the SPRs]. The dose length product (DLP) values of each scan were recorded and the tube current (mA) values of the reconstructed CT images were plotted against the respective Z-axis positions on the phantom. Furthermore, measurements of the noise levels at the center of each phantom section were performed to assess the impact of mA modulation on image quality.Results: The mA modulation patterns of the two CT scanners were very dissimilar. The mA variations were more pronounced for Aquilion 64, where changes in any of the aforementioned scan parameters affected both the mA modulations curves and DLP values. However, the noise levels were affected only by changes in pitch, ST/RI, and AEC protocol selections. For Brilliance 64, changes in pitch affected the mA modulation curves but not the DLP values, whereas only AEC protocol and SPR tube potential selection variations affected both the mA modulation curves and DLP values. The noise levels increased for smaller ST/RI, larger weight category AEC protocol, and larger SPR tube potential selection.Conclusions: The nested PMMA dosimetry phantom can be effectively utilized for the comprehension of CT AEC systems performance and the way that different scan conditions affect the mA modulation patterns, DLP values, and image noise. However, in depth analysis of the reasons why these two systems exhibited such different behaviors in response to the same phantom requires further investigation which is beyond the scope of this study.« less
Hirshon, Jon Mark; Galvagno, Samuel M; Comer, Angela; Millin, Michael G; Floccare, Douglas J; Alcorta, Richard L; Lawner, Benjamin J; Margolis, Asa M; Nable, Jose V; Bass, Robert R
2016-03-01
Helicopter emergency medical services (EMS) has become a well-established component of modern trauma systems. It is an expensive, limited resource with potential safety concerns. Helicopter EMS activation criteria intended to increase efficiency and reduce inappropriate use remain elusive and difficult to measure. This study evaluates the effect of statewide field trauma triage changes on helicopter EMS use and patient outcomes. Data were extracted from the helicopter EMS computer-aided dispatch database for in-state scene flights and from the state Trauma Registry for all trauma patients directly admitted from the scene or transferred to trauma centers from July 1, 2000, to June 30, 2011. Computer-aided dispatch flights were analyzed for periods corresponding to field triage protocol modifications intended to improve system efficiency. Outcomes were separately analyzed for trauma registry patients by mode of transport. The helicopter EMS computer-aided dispatch data set included 44,073 transports. There was a statewide decrease in helicopter EMS usage for trauma patients of 55.9%, differentially affecting counties closer to trauma centers. The Trauma Registry data set included 182,809 patients (37,407 helicopter transports, 128,129 ambulance transports, and 17,273 transfers). There was an increase of 21% in overall annual EMS scene trauma patients transported; ground transports increased by 33%, whereas helicopter EMS transports decreased by 49%. Helicopter EMS patient acuity increased, with an attendant increase in patient mortality. However, when standardized with W statistics, both helicopter EMS- and ground-transported trauma patients showed sustained improvement in mortality. Modifications to state protocols were associated with decreased helicopter EMS use and overall improved trauma patient outcomes. Copyright © 2015 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
A model for assessment and referral of clients with bowel symptoms in community pharmacies.
Sriram, Deepa; McManus, Alexandra; Emmerton, Lynne M; Parsons, Richard W; Jiwa, Moyez
2016-01-01
To expedite diagnosis of serious bowel disease, efforts are required to signpost patients with high-risk symptoms to appropriate care. Community pharmacies are a recognized source of health advice regarding bowel symptoms. This study aimed to examine the effectiveness of a validated self-administered questionnaire, Jodi Lee Test (JLT), for detection, triage, and referral of bowel symptoms suggestive of carcinoma, in pharmacies. 'Usual Practice' was monitored for 12 weeks in 21 pharmacies in Western Australia, documenting outcomes for 84 clients presenting with bowel symptoms. Outcome measures were: acceptance of verbal advice from the pharmacist; general practitioner consultation; and diagnosis. Trial of the JLT involved staff training in the research protocol and monitoring of outcomes for 80 recruited clients over 20 weeks. Utility of the JLT was assessed by post-trial survey of pharmacy staff. Significantly more referrals were made by staff using the JLT than during Usual Practice: 30 (38%) vs 17 (20%). Clients' acceptance of referrals was also higher for the intervention group (40% vs 6%). Two-thirds of pharmacy staff agreed that the JLT could be incorporated into pharmacy practice, and 70% indicated they would use the JLT in the future. A pre-post design was considered more appropriate than a randomized control trial due to an inability to match pharmacies. Limitations of this study were: lack of control over adherence to the study protocol by pharmacy staff; no direct measure of client feedback on the JLT; and loss to follow-up. The JLT was effective in prompting decision-making by pharmacy staff and inter-professional care between pharmacies and general practice, in triage of clients at risk of bowel cancer.
Evaluation of a protocol to optimize duration of pneumonia therapy at hospital discharge.
Caplinger, Christina; Crane, Kendall; Wilkin, Michelle; Bohan, Jefferson; Remington, Richard; Madaras-Kelly, Karl
2016-12-15
A protocol to optimize the duration of antimicrobial therapy (DAT) for uncomplicated pneumonia at hospital discharge was evaluated. This retrospective quasiexperimental study was conducted at Boise Veterans Affairs Medical Center from March 2013 through June 2015. Patients were included in the study if they were diagnosed with pneumonia, were hospitalized for more than 24 hours, received antimicrobial treatment within 48 hours of admission, and survived until hospital discharge. The intervention included development of a pneumonia DAT triage algorithm, a process for assessment of the appropriate DAT by pharmacists, and recommendations to providers to limit excessive discharge DATs prescribed. Interrupted time-series analysis was performed to determine the mean monthly DAT per patient and the 30-day readmission rate. Of the 707 patients discharged with a diagnosis of pneumonia, 560 met the criteria for study inclusion (366 in the preimplementation group and 194 in the postimplementation group). Change in slope of monthly mean DAT per patient postimplementation was significantly reduced (p = 0.03) from the preimplementation slope (p = 0.95), indicating an association between the intervention and mean DAT per patient. The intervention was not associated with the 30-day readmission rate. The mean ± S.D. DAT decreased from 9.5 ± 2.4 days preimplementation to 8.2 ± 2.9 days postimplementation, primarily due to the reduction of outpatient DAT from 5.2 ± 3.0 days preimplementation to 4.2 ± 3.0 days postimplementation. A pharmacy-based triage algorithm helped to reduce excessive DATs for patients with pneumonia at hospital discharge without negatively affecting 30-day readmission rates. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.
Utilization of Veno-Arterial Extracorporeal Membrane Oxygenation for Massive Pulmonary Embolism.
Pasrija, Chetan; Kronfli, Anthony; George, Praveen; Raithel, Maxwell; Boulos, Francesca; Herr, Daniel L; Gammie, James S; Pham, Si M; Griffith, Bartley P; Kon, Zachary N
2018-02-01
The management of massive pulmonary embolism remains challenging, with a considerable mortality rate. Although veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for massive pulmonary embolism has been reported, its use as salvage therapy has been associated with poor outcomes. We reviewed our experience utilizing an aggressive, protocolized approach of VA-ECMO to triage, optimize, and treat these patients. All patients with a massive pulmonary embolism who were placed on VA-ECMO, as an initial intervention determined by protocol, were retrospectively reviewed. ECMO support was continued until organ optimization was achieved or neurologic status was determined. At that time, if the thrombus burden resolved, decannulation was performed. If substantial clot burden was still present with evidence of right ventricular (RV) strain, operative therapy was undertaken. Twenty patients were identified. Before cannulation, all patients had an RV-to-left ventricular ratio greater than 1.0 and severe RV dysfunction. The median duration of ECMO support was 5.1 days, with significant improvement in end-organ function. Ultimately, 40% received anticoagulation alone, 5% underwent catheter-directed therapy, and 55% underwent surgical pulmonary embolectomy. Care was withdrawn in 1 patient with a prolonged pre-cannulation cardiac arrest after confirmation of neurologic death. In-hospital and 90-day survival was 95%. At discharge, 18 of 19 patients had normal RV function, and 1 patient, who received catheter-directed therapy, had mild dysfunction. VA-ECMO appears to be an effective tool to optimize end-organ function as a bridge to recovery or intervention, with excellent outcomes. This approach may allow clinicians to better triage patients with massive pulmonary embolism to the appropriate therapy on the basis of recovery of RV function, residual thrombus burden, operative risk, and neurologic status. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Schäfer, Julia Carmen; Haubenreisser, Holger; Meyer, Mathias; Grüttner, Joachim; Walter, Thomas; Borggrefe, Martin; Schoepf, Joseph U; Nance, John W; Schönberg, Stefan O; Henzler, Thomas
2018-06-01
To prospectively evaluate the feasibility of single contrast bolus high-pitch CT pulmonary angiography (CTPA) subsequently followed by low-dose retrospectively ECG-gated cardiac CT (4D-cCT) in patients with suspected pulmonary embolism (PE) to accurately evaluate right ventricular (RV) function. 62 patients (33 female, age 65.1 ± 17.5 years) underwent high-pitch CTPA examination with 80cc of iodinated contrast material. 5 s after the end of the high-pitch CTPA study, a low-dose retrospectively ECG-gated cardiac CT examination was automatically started. The volume CT dose index (CTDI vol) and dose length product (DLP) were recorded in all patients and the effective dose was calculated. For the assessment of image quality, attenuation was measured as Hounsfield units (HUs) within various regions of interest (ROIs). These ROIs were used to calculate the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Subjective image quality was assessed using a five-point Likert scale. On 4D-cCT, the ejection fraction of both ventricles (RVEF, LVEF) as well as the ratio of RVEF and LVEF (RVEF/LVEF) was assessed. The statistical difference of all parameters between the PE and non-PE group was calculated. The mean effective radiation dose was 4.22 ± 2.05 mSv. Attenuation measurements on CTPA showed the highest attenuation values in the main pulmonary artery (442.01 ± 187.64). On 4D-cCT attenuation values were highest in the descending aorta (560.59 ± 208.81). The CNR and SNR values on CTPA were highest within the main pulmonary artery (CNR = 12.43 ± 4.57; SNR = 15.14 ± 4.90). On 4D-cCT images, the highest SNR and CNR could be measured in the descending aorta (CNR = 10.26 ± 5.57; SNR = 10.86 ± 5.17). The mean LVEF was 60.73 %± 14.65 %, and the mean RVEF was 44.90 %± 9.54 %. The mean RVEF/LVEF was 0.79 ± 0.29. There was no significant difference between the PE and non-PE group for either of the parameters. The investigated combined CTPA and 4D-cCT protocol is feasible using a single contrast bolus and allows the evaluation of RV function in patients with suspected PE. Further studies have to evaluate the additional value of this protocol regarding risk stratification in patients with PE. · High-pitch CTPA is fast enough to leave sufficient contrast material within the heart that can be used for an additional low-dose functional cardiac CT examination.. · The tube current of the evaluated 4D-cCT is reduced over the entire cardiac cycle without any full dose peak.. · Low-dose cardiac CT subsequently performed after high-pitch CTPA allows for detailed analysis of RV function.. · Schäfer JC, Haubenreisser H, Meyer M et al. Feasibility of a Single Contrast Bolus High-Pitch Pulmonary CT Angiography Protocol Followed by Low-Dose Retrospectively ECG-Gated Cardiac CT in Patients with Suspected Pulmonary Embolism. Fortschr Röntgenstr 2018; 190: 542 - 550. © Georg Thieme Verlag KG Stuttgart · New York.
Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children.
Kim, Hyun Gi; Lee, Ho-Joon; Lee, Seung-Koo; Kim, Hyun Ji; Kim, Myung-Joon
2017-09-01
To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols. A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for <3-year-old patients and applied 30% ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V. Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P < 0.001). Qualitative analysis showed higher gray-white matter differentiation and sharpness and preserved overall diagnostic quality in the images with ASIR-V. Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality. • It is possible to reduce radiation dose and improve image quality with ASIR-V. • We improved noise and CNR and decreased radiation dose. • Sharpness improved with ASIR-V. • Total radiation dose was decreased by 12.8% to 34.0%.
Joseph, C; Morrissey, D; Abdur-Rahman, M; Hussenbux, A; Barton, C
2014-12-01
Triage is implemented in healthcare settings to optimise access to appropriate care and manage waiting times. To determine the optimum features of triage systems for patients with musculoskeletal conditions. AMED, BNI, CINAHL, EMBASE, Health Business Elite, HMIC, MEDLINE, Cochrane Library, Web of Science and Google Scholar. Studies that included non-musculoskeletal conditions, concerned patients aged <18 years or were set in emergency departments were excluded. Study quality was graded using the Downs and Black quality index. Qualitative methods were used to further inform the findings of the literature review. Thirty-four studies met the inclusion criteria, with study quality ranging from eight to 24 out of a possible 27. Musculoskeletal triage is conducted via face-to-face consultation, paper referral letter or telephone consultation. Triage performed by physiotherapists, general practitioners, multidisciplinary teams, nurses, occupational therapists and speech therapists has been shown to be effective using a range of outcomes. Qualitative data revealed the value of supportive interdisciplinary teams, and suggested that this support is more important than choice of clinician. Patients trusted, and expressed preferences for, experienced clinicians to perform triage. Triage can be performed effectively via a number of methods and by a range of clinicians. Satisfaction, cost, diagnostic agreement, appropriateness of referral and waiting list time have been improved though triage. Multidisciplinary support mechanisms are critical elements of successful triage systems. Patients are more concerned with access issues than professional boundaries. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Häme, Yrjö; Angelini, Elsa D.; Hoffman, Eric A.; Barr, R. Graham; Laine, Andrew F.
2014-01-01
The extent of pulmonary emphysema is commonly estimated from CT images by computing the proportional area of voxels below a predefined attenuation threshold. However, the reliability of this approach is limited by several factors that affect the CT intensity distributions in the lung. This work presents a novel method for emphysema quantification, based on parametric modeling of intensity distributions in the lung and a hidden Markov measure field model to segment emphysematous regions. The framework adapts to the characteristics of an image to ensure a robust quantification of emphysema under varying CT imaging protocols and differences in parenchymal intensity distributions due to factors such as inspiration level. Compared to standard approaches, the present model involves a larger number of parameters, most of which can be estimated from data, to handle the variability encountered in lung CT scans. The method was used to quantify emphysema on a cohort of 87 subjects, with repeated CT scans acquired over a time period of 8 years using different imaging protocols. The scans were acquired approximately annually, and the data set included a total of 365 scans. The results show that the emphysema estimates produced by the proposed method have very high intra-subject correlation values. By reducing sensitivity to changes in imaging protocol, the method provides a more robust estimate than standard approaches. In addition, the generated emphysema delineations promise great advantages for regional analysis of emphysema extent and progression, possibly advancing disease subtyping. PMID:24759984
Non-Invasive Transcranial Brain Therapy Guided by CT Scans: an In Vivo Monkey Study
NASA Astrophysics Data System (ADS)
Marquet, F.; Pernot, M.; Aubry, J.-F.; Montaldo, G.; Tanter, M.; Boch, A.-L.; Kujas, M.; Seilhean, D.; Fink, M.
2007-05-01
Brain therapy using focused ultrasound remains very limited due to the strong aberrations induced by the skull. A minimally invasive technique using time-reversal was validated recently in-vivo on 20 sheeps. But such a technique requires a hydrophone at the focal point for the first step of the time-reversal procedure. A completely noninvasive therapy requires a reliable model of the acoustic properties of the skull in order to simulate this first step. 3-D simulations based on high-resolution CT images of a skull have been successfully performed with a finite differences code developed in our Laboratory. Thanks to the skull porosity, directly extracted from the CT images, we reconstructed acoustic speed, density and absorption maps and performed the computation. Computed wavefronts are in good agreement with experimental wavefronts acquired through the same part of the skull and this technique was validated in-vitro in the laboratory. A stereotactic frame has been designed and built in order to perform non invasive transcranial focusing in vivo. Here we describe all the steps of our new protocol, from the CT-scans to the therapy treatment and the first in vivo results on a monkey will be presented. This protocol is based on protocols already existing in radiotherapy.
Multiple performance measures are needed to evaluate triage systems in the emergency department.
Zachariasse, Joany M; Nieboer, Daan; Oostenbrink, Rianne; Moll, Henriëtte A; Steyerberg, Ewout W
2018-02-01
Emergency department triage systems can be considered prediction rules with an ordinal outcome, where different directions of misclassification have different clinical consequences. We evaluated strategies to compare the performance of triage systems and aimed to propose a set of performance measures that should be used in future studies. We identified performance measures based on literature review and expert knowledge. Their properties are illustrated in a case study evaluating two triage modifications in a cohort of 14,485 pediatric emergency department visits. Strengths and weaknesses of the performance measures were systematically appraised. Commonly reported performance measures are measures of statistical association (34/60 studies) and diagnostic accuracy (17/60 studies). The case study illustrates that none of the performance measures fulfills all criteria for triage evaluation. Decision curves are the performance measures with the most attractive features but require dichotomization. In addition, paired diagnostic accuracy measures can be recommended for dichotomized analysis, and the triage-weighted kappa and Nagelkerke's R 2 for ordinal analyses. Other performance measures provide limited additional information. When comparing modifications of triage systems, decision curves and diagnostic accuracy measures should be used in a dichotomized analysis, and the triage-weighted kappa and Nagelkerke's R 2 in an ordinal approach. Copyright © 2017 Elsevier Inc. All rights reserved.
Ng, Ming Yen; Karimzad, Yasser; Menezes, Ravi J; Wintersperger, Bernd J; Li, Qin; Forero, Julian; Paul, Narinder S; Nguyen, Elsie T
2016-10-01
To evaluate the heart rate lowering effect of relaxation music in patients undergoing coronary CT angiography (CCTA), pulmonary vein CT (PVCT) and coronary calcium score CT (CCS). Patients were randomised to a control group (i.e. standard of care protocol) or to a relaxation music group (ie. standard of care protocol with music). The groups were compared for heart rate, radiation dose, image quality and dose of IV metoprolol. Both groups completed State-Trait Anxiety Inventory anxiety questionnaires to assess patient experience. One hundred and ninety-seven patients were recruited (61.9 % males); mean age 56y (19-86 y); 127 CCTA, 17 PVCT, 53 CCS. No significant difference in heart rate, radiation dose, image quality, metoprolol dose and anxiety scores. 86 % of patients enjoyed the music. 90 % of patients in the music group expressed a strong preference to have music for future examinations. The patient cohort demonstrated low anxiety levels prior to CT. Relaxation music in CCTA, PVCT and CCS does not reduce heart rate or IV metoprolol use. Patients showed low levels of anxiety indicating that anxiolytics may not have a significant role in lowering heart rate. Music can be used in cardiac CT to improve patient experience. • Relaxation music does not reduce heart rate in cardiac CT • Relaxation music does not reduce beta-blocker use in cardiac CT • Relaxation music has no effect on cardiac CT image quality • Low levels of anxiety are present in patients prior to cardiac CT • Patients enjoyed the relaxation music and this results in improved patient experience.
Bennin, Charles-Lwanga K; Ibrahim, Saif; Al-Saffar, Farah; Box, Lyndon C; Strom, Joel A
2016-10-01
ST-elevation myocardial infarction (STEMI) guidelines recommend reperfusion by primary percutaneous coronary intervention (PCI) ≤ 90 min from time of first medical contact (FMC). This strategy is challenging in rural areas lacking a nearby PCI-capable hospital. Recommended reperfusion times can be achieved for STEMI patients presenting in rural areas without a nearby PCI-capable hospital by ground transportation to a central PCI-capable hospital by use of protocol-driven emergency medical service (EMS) STEMI field triage protocol. Sixty STEMI patients directly transported by EMS from three rural counties (Nassau, Camden and Charlton Counties) within a 50-mile radius of University of Florida Health-Jacksonville (UFHJ) from 01/01/2009 to 12/31/2013 were identified from its PCI registry. The STEMI field triage protocol incorporated three elements: (1) a cooperative agreement between each of the rural emergency medical service (EMS) agency and UFHJ; (2) performance of a pre-hospital ECG to facilitate STEMI identification and laboratory activation; and (3) direct transfer by ground transportation to the UFHJ cardiac catheterization laboratory. FMC-to-device (FMC2D), door-to-device (D2D), and transit times, the day of week, time of day, and EMS shift times were recorded, and odds ratio (OR) of achieving FMC2D times was calculated. FMC2D times were shorter for in-state STEMIs (81 ± 17 vs . 87 ± 19 min), but D2D times were similar (37 ± 18 vs . 39 ± 21 min). FMC2D ≤ 90 min were achieved in 82.7% in-state STEMIs compared to 52.2% for out-of-state STEMIs (OR = 4.4, 95% CI: 1.24-15.57; P = 0.018). FMC2D times were homogenous after adjusting for weekday vs . weekend, EMS shift times. Nine patients did not meet FMC2D ≤ 90 min. Six were within 10 min of target; all patient achieved FMC2D ≤ 120 min. Guideline-compliant FMC2D ≤ 90 min is achievable for rural STEMI patients within a 50 mile radius of a PCI-capable hospital by use of protocol-driven EMS ground transportation. As all patients achieved a FMC2D time ≤ 120 min, bypass of non-PCI capable hospitals may be reasonable in this situation.
Moore, Christopher L.; Daniels, Brock; Singh, Dinesh; Luty, Seth; Gunabushanam, Gowthaman; Ghita, Monica; Molinaro, Annette; Gross, Cary P.
2016-01-01
Purpose To determine if a reduced-dose computed tomography (CT) protocol could effectively help to identify patients in the emergency department (ED) with moderate to high likelihood of calculi who would require urologic intervention within 90 days. Materials and Methods The study was approved by the institutional review board and written informed consent with HIPAA authorization was obtained. This was a prospective, single-center study of patients in the ED with moderate to high likelihood of ureteral stone undergoing CT imaging. Objective likelihood of ureteral stone was determined by using the previously derived and validated STONE clinical prediction rule, which includes five elements: sex, timing, origin, nausea, and erythrocytes. All patients with high STONE score (STONE score, 10–13) underwent reduced-dose CT, while those with moderate likelihood of ureteral stone (moderate STONE score, 6–9) underwent reduced-dose CT or standard CT based on clinician discretion. Patients were followed to 90 days after initial imaging for clinical course and for the primary outcome of any intervention. Statistics are primarily descriptive and are reported as percentages, sensitivities, and specificities with 95% confidence intervals. Results There were 264 participants enrolled and 165 reduced-dose CTs performed; of these participants, 108 underwent reduced-dose CT alone with complete follow-up. Overall, 46 of 264 (17.4%) of patients underwent urologic intervention, and 25 of 108 (23.1%) patients who underwent reduced-dose CT underwent a urologic intervention; all were correctly diagnosed on the clinical report of the reduced-dose CT (sensitivity, 100%; 95% confidence interval: 86.7%, 100%). The average dose-length product for all standard-dose CTs was 857 mGy · cm ± 395 compared with 101 mGy · cm ± 39 for all reduced-dose CTs (average dose reduction, 88.2%). There were five interventions for nonurologic causes, three of which were urgent and none of which were missed when reduced-dose CT was performed. Conclusion A CT protocol with over 85% dose reduction can be used in patients with moderate to high likelihood of ureteral stone to safely and effectively identify patients in the ED who will require urologic intervention. PMID:26943230
"RAPID" team triage: one hospital's approach to patient-centered team triage.
Shea, Sheila Sanning; Hoyt, K Sue
2012-01-01
Patients who present to the emergency department want definitive care by a health care provider who can perform an initial assessment, initiate treatment, and implement a disposition plan. The traditional "nurse triage" model often creates barriers to the process of rapidly evaluating patients. Therefore, innovative strategies must be explored to improve the time of patient arrival to the time seen by a qualified provider in order to complete a thorough medical screening examination. One such approach is a rapid team triage system that provides a patient-centered process. This article describes the implementation of a rapid team triage model in an urban community hospital.
The optimal imaging strategy for patients with stable chest pain: a cost-effectiveness analysis.
Genders, Tessa S S; Petersen, Steffen E; Pugliese, Francesca; Dastidar, Amardeep G; Fleischmann, Kirsten E; Nieman, Koen; Hunink, M G Myriam
2015-04-07
The optimal imaging strategy for patients with stable chest pain is uncertain. To determine the cost-effectiveness of different imaging strategies for patients with stable chest pain. Microsimulation state-transition model. Published literature. 60-year-old patients with a low to intermediate probability of coronary artery disease (CAD). Lifetime. The United States, the United Kingdom, and the Netherlands. Coronary computed tomography (CT) angiography, cardiac stress magnetic resonance imaging, stress single-photon emission CT, and stress echocardiography. Lifetime costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. The strategy that maximized QALYs and was cost-effective in the United States and the Netherlands began with coronary CT angiography, continued with cardiac stress imaging if angiography found at least 50% stenosis in at least 1 coronary artery, and ended with catheter-based coronary angiography if stress imaging induced ischemia of any severity. For U.K. men, the preferred strategy was optimal medical therapy without catheter-based coronary angiography if coronary CT angiography found only moderate CAD or stress imaging induced only mild ischemia. In these strategies, stress echocardiography was consistently more effective and less expensive than other stress imaging tests. For U.K. women, the optimal strategy was stress echocardiography followed by catheter-based coronary angiography if echocardiography induced mild or moderate ischemia. Results were sensitive to changes in the probability of CAD and assumptions about false-positive results. All cardiac stress imaging tests were assumed to be available. Exercise electrocardiography was included only in a sensitivity analysis. Differences in QALYs among strategies were small. Coronary CT angiography is a cost-effective triage test for 60-year-old patients who have nonacute chest pain and a low to intermediate probability of CAD. Erasmus University Medical Center.
Klein, Kelly R.; Burkle Jr., Frederick M.; Swienton, Raymond; King, Richard V.; Lehman, Thomas; North, Carol S.
2016-01-01
Introduction: After all large-scale disasters multiple papers are published describing the shortcomings of the triage methods utilized. This paper uses medical provider input to help describe attributes and patient characteristics that impact triage decisions. Methods: A survey distributed electronically to medical providers with and without disaster experience. Questions asked included what disaster experiences they had, and to rank six attributes in order of importance regarding triage. Results: 403 unique completed surveys were analyzed. 92% practiced a structural triage approach with the rest reporting they used “gestalt”.(gut feeling) Twelve per cent were identified as having placed patients in an expectant category during triage. Respiratory status, ability to speak, perfusion/pulse were all ranked in the top three. Gut feeling regardless of statistical analysis was fourth. Supplies were ranked in the top four when analyzed for those who had placed patients in the expectant category. Conclusion: Primary triage decisions in a mass casualty scenario are multifactorial and encompass patient mobility, life saving interventions, situational instincts, and logistics. PMID:27651979
Liang, Chun-Yang; Yang, Yang; Shen, Chun-Sen; Wang, Hai-Jiang; Liu, Nai-Ming; Wang, Zhi-Wen; Zhu, Feng-Lei; Xu, Ru-Xiang
2018-02-06
Secondary brain injury is the main cause of mortality from traumatic brain injury (TBI). One hallmark of TBI is intracranial hemorrhage, which occurs in 40-50% of severe TBI cases. Early identification of intracranial hematomas in TBI patients allows early surgical evacuation and can reduce the case fatality rate of TBI. As pre-hospital care is the weakest part of Chinese emergency care, there is an urgent need for a capability to detect brain hematomas early. In China, in addition to preventing injuries and diseases in military staff and in enhancing the military armed forces during war, military medicine participates in actions such as emergency public health crises, natural disasters, emerging conflicts, and anti-terrorist campaigns during peacetime. The purpose of this observational study is to evaluate in the Chinese military general hospital the performance of a near-infrared (NIR)-based portable device, developed for US Military, in the detection of traumatic intracranial hematomas. The endpoint of the study was a description of the test characteristics (sensitivity, specificity, and positive and negative predictive values [NPV]) of the portable NIR-based device in identification of hematomas within its detection limits (volume >3.5 mL and depth <2.5 cm) compared with computed tomography (CT) scans as the gold standard. The Infrascanner Model 2000 NIR device (InfraScan, Inc., Philadelphia, PA, USA) was used for hematoma detection in patients sustaining TBI. Data were collected in the People's Liberation Army General Hospital in Beijing using the NIR device at the time of CT scans, which were performed to evaluate suspected TBI. One hundred and twenty seven patients were screened, and 102 patients were included in the per protocol population. Of the 102 patients, 24 were determined by CT scan to have intracranial hemorrhage. The CT scans were read by an independent neuroradiologist who was blinded to the NIR measurements. The NIR device demonstrated sensitivity of 100% (95% confidence intervals [CI] 82.8-100%) and specificity of 93.6% (95%CI 85-97.6%) in detecting intracranial hematomas larger than 3.5 mL in volume and that were less than 2.5 cm from the surface of the brain. Blood contained within scalp hematomas was found to be a major cause of false-positive results with this technology. The study showed that the Infrascanner is a suitable portable device in Chinese population for detecting preoperative intracranial hematomas in remote locations, emergency rooms, and intensive care units. It could aid military medics, physicians, and hospital staff, permitting better triage decisions, earlier treatment, and reducing secondary brain injury caused by acute and delayed hematomas. © Association of Military Surgeons of the United States 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Lima, Fabricio O.; Silva, Gisele S.; Furie, Karen L.; Frankel, Michael R.; Lev, Michael H.; Camargo, Érica CS; Haussen, Diogo C.; Singhal, Aneesh B.; Koroshetz, Walter J.; Smith, Wade S.; Nogueira, Raul G.
2016-01-01
Background and Purpose Patients with large vessel occlusion strokes (LVOS) may be better served by direct transfer to endovascular capable centers avoiding hazardous delays between primary and comprehensive stroke centers. However, accurate stroke field triage remains challenging. We aimed to develop a simple field scale to identify LVOS. Methods The FAST-ED scale was based on items of the NIHSS with higher predictive value for LVOS and tested in the STOPStroke cohort, in which patients underwent CT angiography within the first 24 hours of stroke onset. LVOS were defined by total occlusions involving the intracranial-ICA, MCA-M1, MCA-2, or basilar arteries. Patients with partial, bi-hemispheric, and/or anterior + posterior circulation occlusions were excluded. Receiver operating characteristic (ROC) curve, sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of FAST-ED were compared with the NIHSS, Rapid Arterial oCclusion Evaluation (RACE) scale and Cincinnati Prehospital Stroke Severity Scale (CPSSS). Results LVO was detected in 240 of the 727 qualifying patients (33%). FAST-ED had comparable accuracy to predict LVO to the NIHSS and higher accuracy than RACE and CPSS (area under the ROC curve: FAST-ED=0.81 as reference; NIHSS=0.80, p=0.28; RACE=0.77, p=0.02; and CPSS=0.75, p=0.002). A FAST-ED ≥4 had sensitivity of 0.60, specificity 0.89, PPV 0.72, and NPV 0.82 versus RACE ≥5 of 0.55, 0.87, 0.68, 0.79 and CPSS ≥2 of 0.56, 0.85, 0.65, 0.78, respectively. Conclusions FAST-ED is a simple scale that if successfully validated in the field may be used by medical emergency professionals to identify LVOS in the pre-hospital setting enabling rapid triage of patients. PMID:27364531
Graham, R N J
2012-01-01
With the increasing tempo of military conflicts in the last decade, much has been learnt about imaging battlefield casualties in the acute setting. Ultrasound in the form of focused abdominal sonography in trauma (FAST) has proven invaluable in emergency triage of patients for immediate surgery. Multidetector CT allows accurate determination of battlefield trauma injuries. It permits the surgeons and anaesthetists to plan their interventions more thoroughly and to be made aware of clinically occult injuries. There are common injury patterns associated with blast injury, gunshot wounds and blunt trauma. While this body of knowledge is most applicable to the battlefield, there are parallels with peacetime radiology, particularly in terrorist attacks and industrial accidents. This pictorial review is based on the experiences of a UK radiologist deployed in Afghanistan in 2010. PMID:22806621
Radiation dose reduction in parasinus CT by spectral shaping.
May, Matthias S; Brand, Michael; Lell, Michael M; Sedlmair, Martin; Allmendinger, Thomas; Uder, Michael; Wuest, Wolfgang
2017-02-01
Spectral shaping aims to narrow the X-ray spectrum of clinical CT. The aim of this study was to determine the image quality and the extent of radiation dose reduction that can be achieved by tin prefiltration for parasinus CT. All scans were performed with a third generation dual-source CT scanner. A study protocol was designed using 100 kV tube voltage with tin prefiltration (200 mAs) that provides image noise levels comparable to a low-dose reference protocol using 100 kV without spectral shaping (25 mAs). One hundred consecutive patients were prospectively enrolled and randomly assigned to the study or control group. All patients signed written informed consent. The study protocol was approved by the local Institutional Review Board and applies to the HIPAA. Subjective and objective image quality (attenuation values, image noise, and contrast-to-noise ratio (CNR)) were assessed. Radiation exposure was assessed as volumetric CT dose index, and effective dose was estimated. Mann-Whitney U test was performed for radiation exposure and for image noise comparison. All scans were of diagnostic image quality. Image noise in air, in the retrobulbar fat, and in the eye globe was comparable between both groups (all p > 0.05). CNR eye globe/air did not differ significantly between both groups (p = 0.7). Radiation exposure (1.7 vs. 2.1 mGy, p < 0.01) and effective dose (0.055 vs. 0.066 mSv, p < 0.01) were significantly reduced in the study group. Radiation dose can be further reduced by 17% for low-dose parasinus CT by tin prefiltration maintaining diagnostic image quality.
SU-E-T-669: Radiosurgery Failure for Trigeminal Neuralgia: A Study of Radiographic Spatial Fidelity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Howe, J; Spalding, A
Purpose: Management of Trigeminal Neuralgia with radiosurgery is well established, but often met with limited success. Recent advancements in imaging afford improvements in target localization for radiosurgery. Methods: A Trigeminal Neuralgia radiosurgery specific protocol was established for MR enhancement of the trigeminal nerve using a CISS scan with slice spacing of 0.7mm. Computed Tomography simulation was performed using axial slices on a 40 slice CT with slice spacing of 0.6mm. These datasets were registered using a mutual information algorithm and localized in a stereotactic coordinate system. Image registration between the MR and CT was evaluated for each patient by amore » Medical Physicist to ensure accuracy. The dorsal root entry zone target was defined on the CISS MR by a Neurosurgeon and dose calculations performed on the localized CT. Treatment plans were reviewed and approved by a Radiation Oncologist and Neurosurgeon. Image guided radiosurgery was delivered using positioning tolerance of 0.5mm and 1°. Eight patients with Trigeminal Neuralgia were treated with this protocol. Results: Seven patients reported a favorable response to treatment with average Barrow Neurological Index pain score of four before treatment and one following treatment. Only one patient had a BNI>1 following treatment and review of the treatment plan revealed that the CISS MR was registered to the CT via a low resolution (5mm slice spacing) T2 MR. All other patients had CISS MR registered directly with the localized CT. This patient was retreated 6 months later using direct registration between CISS MR and localized CT and subsequently responded to treatment with a BNI of one. Conclusion: Frameless radiosurgery offers an effective solution to Trigeminal Neuralgia management provided appropriate technology and imaging protocols (utilizing submillimeter imaging) are established and maintained.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elzibak, A; Safigholi, H; Soliman, A
2015-06-15
Purpose: To examine CT metal image artifact from a novel direction-modulated brachytherapy (DMBT) tandem applicator (95% tungsten) for cervical cancer using a commercially available orthopedic metal artifact reduction (O-MAR) algorithm. Comparison to a conventional stainless steel applicator is also performed. Methods: Each applicator was placed in a water-filled phantom resembling the female pelvis and scanned in a Philips Brilliance 16-slice CT scanner using two pelvis protocols: a typical clinical protocol (120kVp, 16×0.75mm collimation, 0.692 pitch, 1.0s rotation, 350mm field of view (FOV), 600mAs, 1.5mm slices) and a protocol with a higher kVp and mAs setting useful for larger patients (140kVp,more » 16×0.75mm collimation, 0.688 pitch, 1.5s rotation, 350mm FOV, 870mAs, 1.5mm slices). Images of each tandem were acquired with and without the application of the O-MAR algorithm. Baseline scans of the phantom (no applicator) were also collected. CT numbers were quantified at distances from 5 to 30 mm away from the applicator’s edge (in increments of 5mm) using measurements at eight angles around the applicator, on three consecutive slices. Results: While the presence of both applicators degraded image quality, the DMBT applicator resulted in larger streaking artifacts and dark areas in the image compared to the stainless steel applicator. Application of the O-MAR algorithm improved all acquired images, both visually and quantitatively. The use of low and high kVp and mAs settings (120 kVp/600mAs and 140 kVp/870mAs) in conjunction with the O-MAR algorithm lead to similar CT numbers in the vicinity of the applicator and a similar reduction of the induced metal artifact. Conclusion: This work indicated that metal artifacts induced by the DMBT and the stainless steel applicator are greatly reduced when using the O-MAR algorithm, leading to better quality phantom images. The use of a high dose protocol provided similar improvements in metal artifacts compared to the clinical protocol.« less
Early dynamic 18F-FDG PET to detect hyperperfusion in hepatocellular carcinoma liver lesions.
Schierz, Jan-Henning; Opfermann, Thomas; Steenbeck, Jörg; Lopatta, Eric; Settmacher, Utz; Stallmach, Andreas; Marlowe, Robert J; Freesmeyer, Martin
2013-06-01
In addition to angiographic data on vascularity and vascular access, demonstration of hepatocellular carcinoma (HCC) liver nodule hypervascularization is a prerequisite for certain intrahepatic antitumor therapies. Early dynamic (ED) (18)F-FDG PET/CT could serve this purpose when the current standard method, contrast-enhanced (CE) CT, or other CE morphologic imaging modalities are unsuitable. A recent study showed ED (18)F-FDG PET/CT efficacy in this setting but applied a larger-than-standard (18)F-FDG activity and an elaborate protocol likely to hinder routine use. We developed a simplified protocol using standard activities and easily generated visual and descriptive or quantitative endpoints. This pilot study assessed the ability of these endpoints to detect HCC hyperperfusion and, thereby, evaluated the suitability in of the protocol everyday practice. Twenty-seven patients with 34 HCCs (diameter ≥ 1.5 cm) with hypervascularization on 3-phase CE CT underwent liver ED (18)F-FDG PET for 240 s, starting with (18)F-FDG (250-MBq bolus injection). Four frames at 15-s intervals, followed by 3 frames at 60-s intervals were reconstructed. Endpoints included focal tracer accumulation in the first 4 frames (60 s), subsequent focal washout, and visual and quantitative differences between tumor and liver regions of interest in maximum and mean ED standardized uptake value (ED SUVmax and ED SUVmean, respectively) 240-s time-activity curves. All 34 lesions were identified by early focal (18)F-FDG accumulation and faster time-to-peak ED SUVmax or ED SUVmean than in nontumor tissue. Tumor peak ED SUVmax and ED SUVmean exceeded liver levels in 85% and 53%, respectively, of lesions. Nadir tumor signal showed no consistent pattern relative to nontumor signal. HCC had a significantly shorter time to peak and significantly faster rate to peak for both ED SUVmax and ED SUVmean curves and a significantly higher peak ED SUVmax but not peak ED SUVmean than the liver. This pilot study provided proof of principle that our simplified ED (18)F-FDG PET/CT protocol includes endpoints that effectively detect HCC hypervascularization; this finding suggests that the protocol can be used routinely.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mein, S; Rankine, L; Department of Radiation Oncology, Washington University School of Medicine
Purpose: To develop, evaluate and apply a novel high-resolution 3D remote dosimetry protocol for validation of MRI guided radiation therapy treatments (MRIdian by ViewRay™). We demonstrate the first application of the protocol (including two small but required new correction terms) utilizing radiochromic 3D plastic PRESAGE™ with optical-CT readout. Methods: A detailed study of PRESAGE™ dosimeters (2kg) was conducted to investigate the temporal and spatial stability of radiation induced optical density change (ΔOD) over 8 days. Temporal stability was investigated on 3 dosimeters irradiated with four equally-spaced square 6MV fields delivering doses between 10cGy and 300cGy. Doses were imaged (read-out) bymore » optical-CT at multiple intervals. Spatial stability of ΔOD response was investigated on 3 other dosimeters irradiated uniformly with 15MV extended-SSD fields with doses of 15cGy, 30cGy and 60cGy. Temporal and spatial (radial) changes were investigated using CERR and MATLAB’s Curve Fitting Tool-box. A protocol was developed to extrapolate measured ΔOD readings at t=48hr (the typical shipment time in remote dosimetry) to time t=1hr. Results: All dosimeters were observed to gradually darken with time (<5% per day). Consistent intra-batch sensitivity (0.0930±0.002 ΔOD/cm/Gy) and linearity (R2=0.9996) was observed at t=1hr. A small radial effect (<3%) was observed, attributed to curing thermodynamics during manufacture. The refined remote dosimetry protocol (including polynomial correction terms for temporal and spatial effects, CT and CR) was then applied to independent dosimeters irradiated with MR-IGRT treatments. Excellent line profile agreement and 3D-gamma results for 3%/3mm, 10% threshold were observed, with an average passing rate 96.5%± 3.43%. Conclusion: A novel 3D remote dosimetry protocol is presented capable of validation of advanced radiation treatments (including MR-IGRT). The protocol uses 2kg radiochromic plastic dosimeters read-out by optical-CT within a week of treatment. The protocol requires small corrections for temporal and spatially-dependent behaviors observed between irradiation and readout.« less
Thomas, Christoph; Krauss, Bernhard; Ketelsen, Dominik; Tsiflikas, Ilias; Reimann, Anja; Werner, Matthias; Schilling, David; Hennenlotter, Jörg; Claussen, Claus D; Schlemmer, Heinz-Peter; Heuschmid, Martin
2010-07-01
In dual energy (DE) computed tomography (CT), spectral shaping by additional filtration of the high energy spectrum can theoretically improve dual energy contrast. The aim of this in vitro study was to examine the influence of an additional tin filter for the differentiation of human urinary calculi by dual energy CT. A total of 36 pure human urinary calculi (uric acid, cystine, calciumoxalate monohydrate, calciumoxalate dihydrate, carbonatapatite, brushite, average diameter 10.5 mm) were placed in a phantom and imaged with 2 dual source CT scanners. One scanner was equipped with an additional tin (Sn) filter. Different combinations of tube voltages (140/80 kV, 140/100 kV, Sn140/100 kV, Sn140/80 kV, with Sn140 referring to 140 kV with the tin filter) were applied. Tube currents were adapted to yield comparable dose indices. Low- and high energy images were reconstructed. The calculi were segmented semiautomatically in the datasets and DE ratios (attenuation@low_kV/attenuation@high_kV) and were calculated for each calculus. DE contrasts (DE-ratio_material1/DE-ratio_material2) were computed for uric acid, cystine and calcified calculi and compared between the combinations of tube voltages. Using exclusively DE ratios, all uric acid, cystine and calcified calculi (as a group) could be differentiated in all protocols; the calcified calculi could not be differentiated among each other in any examination protocol. The highest DE ratios and DE contrasts were measured for the Sn140/80 protocol (53%-62% higher DE contrast than in the 140/80 kV protocol without additional filtration). The DE ratios and DE contrasts of the 80/140 kV and 100/Sn140 kV protocols were comparable. Uric acid, cystine and calcified calculi could be reliably differentiated by any of the protocols. A dose-neutral gain of DE contrast was found in the Sn-filter protocols, which might improve the differentiation of smaller calculi (Sn140/80 kV) and improve image quality and calculi differentiation in larger patients (Sn140/100 kV). However, even with the improved spectral separation of the Sn-filter protocols, the DE ratios of calcified calculi are not sufficiently distinct to allow a differentiation within this group.
Reorganising the pandemic triage processes to ethically maximise individuals' best interests.
Tillyard, Andrew
2010-11-01
To provide a revised definition, process and purpose of triage to maximise the number of patients receiving intensive care during a crisis. Based on the ethical principle of virtue ethics and the underlying goal of providing individual patients with treatment according to their best interests, the methodology of triage is reassessed and revised. The decision making processes regarding treatment decisions during a pandemic are redefined and new methods of intensive care provision recommended as well as recommending the use of a 'ranking' system for patients excluded from intensive care, defining the role of non-intensive care specialists, and applying two types of triage as 'organisational triage' and 'treatment triage' based on the demand for intensive care. Using a different underlying ethical basis upon which to plan for a pandemic crisis could maximise the number of patients receiving intensive care based on individual patients' best interests.
Bischel, Alexander; Stratis, Andreas; Bosmans, Hilde; Jacobs, Reinhilde; Gassner, Eva-Maria; Puelacher, Wolfgang; Pauwels, Ruben
2017-01-01
Objectives: The objective of this study was to determine how iterative reconstruction technology (IRT) influences contrast and spatial resolution in ultralow-dose dentomaxillofacial CT imaging. Methods: A polymethyl methacrylate phantom with various inserts was scanned using a reference protocol (RP) at CT dose index volume 36.56 mGy, a sinus protocol at 18.28 mGy and ultralow-dose protocols (LD) at 4.17 mGy, 2.36 mGy, 0.99 mGy and 0.53 mGy. All data sets were reconstructed using filtered back projection (FBP) and the following IRTs: adaptive statistical iterative reconstructions (ASIRs) (ASIR-50, ASIR-100) and model-based iterative reconstruction (MBIR). Inserts containing line-pair patterns and contrast detail patterns for three different materials were scored by three observers. Observer agreement was analyzed using Cohen's kappa and difference in performance between the protocols and reconstruction was analyzed with Dunn's test at α = 0.05. Results: Interobserver agreement was acceptable with a mean kappa value of 0.59. Compared with the RP using FBP, similar scores were achieved at 2.36 mGy using MBIR. MIBR reconstructions showed the highest noise suppression as well as good contrast even at the lowest doses. Overall, ASIR reconstructions did not outperform FBP. Conclusions: LD and MBIR at a dose reduction of >90% may show no significant differences in spatial and contrast resolution compared with an RP and FBP. Ultralow-dose CT and IRT should be further explored in clinical studies. PMID:28059562
Standardization and Optimization of Computed Tomography Protocols to Achieve Low-Dose
Chin, Cynthia; Cody, Dianna D.; Gupta, Rajiv; Hess, Christopher P.; Kalra, Mannudeep K.; Kofler, James M.; Krishnam, Mayil S.; Einstein, Andrew J.
2014-01-01
The increase in radiation exposure due to CT scans has been of growing concern in recent years. CT scanners differ in their capabilities and various indications require unique protocols, but there remains room for standardization and optimization. In this paper we summarize approaches to reduce dose, as discussed in lectures comprising the first session of the 2013 UCSF Virtual Symposium on Radiation Safety in Computed Tomography. The experience of scanning at low dose in different body regions, for both diagnostic and interventional CT procedures, is addressed. An essential primary step is justifying the medical need for each scan. General guiding principles for reducing dose include tailoring a scan to a patient, minimizing scan length, use of tube current modulation and minimizing tube current, minimizing-tube potential, iterative reconstruction, and periodic review of CT studies. Organized efforts for standardization have been spearheaded by professional societies such as the American Association of Physicists in Medicine. Finally, all team members should demonstrate an awareness of the importance of minimizing dose. PMID:24589403
Rani, K; Jahnen, A; Noel, A; Wolf, D
2015-07-01
In the last decade, several studies have emphasised the need to understand and optimise the computed tomography (CT) procedures in order to reduce the radiation dose applied to paediatric patients. To evaluate the influence of the technical parameters on the radiation dose and the image quality, a statistical model has been developed using the design of experiments (DOE) method that has been successfully used in various fields (industry, biology and finance) applied to CT procedures for the abdomen of paediatric patients. A Box-Behnken DOE was used in this study. Three mathematical models (contrast-to-noise ratio, noise and CTDI vol) depending on three factors (tube current, tube voltage and level of iterative reconstruction) were developed and validated. They will serve as a basis for the development of a CT protocol optimisation model. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
ED Triage Decision-Making With Mental Health Presentations: A "Think Aloud" Study.
Clarke, Diana E; Boyce-Gaudreau, Krystal; Sanderson, Ana; Baker, John A
2015-11-01
Triage is the process whereby persons presenting to the emergency department are quickly assessed by a nurse and their need for care and service is prioritized. Research examining the care of persons presenting to emergency departments with psychiatric and mental health problems has shown that triage has often been cited as the most problematic aspect of the encounter. Three questions guided this investigation: Where do the decisions that triage nurses make fall on the intuitive versus analytic dimensions of decision making for mental health presentations in the emergency department, and does this differ according to comfort or familiarity with the type of mental health/illness presentation? How do "decision aids" (i.e., structured triage scales) help in the decision-making process? To what extent do other factors, such as attitudes, influence triage nurses' decision making? Eleven triage nurses participating in this study were asked to talk out loud about the reasoning process they would engage in while triaging patients in 5 scenarios based on mental health presentations to the emergency department. Themes emerging from the data were tweaking the results (including the use of intuition and early judgments) to arrive at the desired triage score; consideration of the current ED environment; managing uncertainty and risk (including the consideration of physical reasons for presentation); and confidence in communicating with patients in distress and managing their own emotive reactions to the scenario. Findings support the preference for using the intuitive mode of decision making with only tacit reliance on the decision aid. Copyright © 2015 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.
Addressing the third delay: implementing a novel obstetric triage system in Ghana.
Goodman, David M; Srofenyoh, Emmanuel K; Ramaswamy, Rohit; Bryce, Fiona; Floyd, Liz; Olufolabi, Adeyemi; Tetteh, Cecilia; Owen, Medge D
2018-01-01
Institutional delivery has been proposed as a method for reducing maternal morbidity and mortality, but little is known about how referral hospitals in low-resource settings can best manage the expected influx of patients. In this study, we assess the impact of an obstetric triage improvement programme on reducing hospital-based delay in a referral hospital in Accra, Ghana. An Active Implementation Framework is used to describe a 5-year intervention to introduce and monitor obstetric triage capabilities. Baseline data, collected from September to November 2012, revealed significant delays in patient assessment on arrival. A triage training course and monitoring of quality improvement tools occurred in 2013 and 2014. Implementation barriers led to the construction of a free-standing obstetric triage pavilion, opened January 2015, with dedicated midwives. Data were collected at three time intervals following the triage pavilion opening and compared with baseline including: referral indications, patient and labour characteristics, waiting time from arrival to assessment and the documentation of a care plan. An obstetric triage improvement programme reduced the median (IQR) patient waiting time from facility arrival to first assessment by a midwife from 40 min (15-100) to 5 min (2-6) (p<0.001) over the 5-year intervention. The triage pavilion enhanced performance resulting in the elimination of previous delays associated with the time of admission and disease acuity. Care plan documentation increased from 51% to 96%. Obstetric triage, when properly implemented, reduced delay in a busy, low-resource hospital. The implementation process was sustained under local leadership during transition to a new hospital.
Computed Tomography of the Abdomen in Eight Clinically Normal Common Marmosets (Callithrix jacchus).
du Plessis, W M; Groenewald, H B; Elliott, D
2017-08-01
The aim of this study was to provide a detailed anatomical description of the abdomen in the clinically normal common marmoset by means of computed tomography (CT). Eight clinically healthy mature common marmosets ranging from 12 to 48 months and 235 to 365 g bodyweight were anesthetized and pre- and post-contrast CT examinations were performed using different CT settings in dorsal recumbency. Abdominal organs were identified and visibility noted. Diagnostic quality abdominal images could be obtained of the common marmoset despite its small size using a dual-slice CT scanner. Representative cross-sectional images were chosen from different animals illustrating the abdominal CT anatomy of clinically normal common marmosets. Identification or delineation of abdominal organs greatly improved with i.v. contrast. A modified high-frequency algorithm with edge enhancement added valuable information for identification of small structures such as the ureters. The Hounsfield unit (HU) of major abdominal organs differed from that of small animals (domestic dogs and cats). Due to their size and different anatomy, standard small animal CT protocols need to be critically assessed and adapted for exotics, such as the common marmoset. The established normal reference range of HU of major abdominal organs and adapted settings for a CT protocol will aid clinical assessment of the common marmoset. © 2017 Blackwell Verlag GmbH.
An evaluation of the use of oral contrast media in abdominopelvic CT.
Buttigieg, Erica Lauren; Grima, Karen Borg; Cortis, Kelvin; Soler, Sandro Galea; Zarb, Francis
2014-11-01
To evaluate the diagnostic efficacy of different oral contrast media (OCM) for abdominopelvic CT examinations performed for follow-up general oncological indications. The objectives were to establish anatomical image quality criteria for abdominopelvic CT; use these criteria to evaluate and compare image quality using positive OCM, neutral OCM and no OCM; and evaluate possible benefits for the medical imaging department. Forty-six adult patients attending a follow-up abdominopelvic CT for general oncological indications and who had a previous abdominopelvic CT with positive OCM (n = 46) were recruited and prospectively placed into either the water (n = 25) or no OCM (n = 21) group. Three radiologists performed absolute visual grading analysis (VGA) to assess image quality by grading the fulfilment of 24 anatomical image quality criteria. Visual grading characteristics (VGC) analysis of the data showed comparable image quality with regards to reproduction of abdominal structures, bowel discrimination, presence of artefacts, and visualization of the amount of intra-abdominal fat for the three OCM protocols. All three OCM protocols provided similar image quality for follow-up abdominopelvic CT for general oncological indications. • Positive oral contrast media are routinely used for abdominopelvic multidetector computed tomography • Experimental study comparing image quality using three different oral contrast materials • Three different oral contrast materials result in comparable CT image quality • Benefits for patients and medical imaging department.
Cardona Arboniés, J; Rodríguez Alfonso, B; Mucientes Rasilla, J; Martínez Ballesteros, C; Zapata Paz, I; Prieto Soriano, A; Carballido Rodriguez, J; Mitjavila Casanovas, M
To evaluate the role of the 18 F-Choline PET/CT in prostate cancer management when detecting distant disease in planning radiotherapy and staging and to evaluate the therapy changes guided by PET/TC results. A retrospective evaluation was performed on 18 F-Choline PET/CT scans of patients with prostate cancer. Staging and planning radiotherapy scans were selected in patients with at least 9 months follow up. There was a total of 56 studies, 33 (58.93%) for staging, and 23 (41.07%) for planning radiotherapy. All scans were obtained using a hybrid PET/CT scanner. The PET/CT acquisition protocol consisted of a dual-phase procedure after the administration of an intravenous injection of 296-370MBq of 18 F-Choline. There were 43 out of 56 (76.8%) scans considered as positive, and 13 (23.2%) were negative. The TNM staging was changed in 13 (23.2%) scans. The PET/CT findings ruled out distant disease in 4 out of 13 scans, and unknown distant disease was detected in 9 (69.3%) scans. 18 F-Choline PET/CT is a useful technique for detecting unknown distant disease in prostate cancer when staging and planning radiotherapy. The inclusion of 18 F-choline PET/CT should be considered in prostate cancer management protocols. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.
Do poison center triage guidelines affect healthcare facility referrals?
Benson, B E; Smith, C A; McKinney, P E; Litovitz, T L; Tandberg, W D
2001-01-01
The purpose of this study was to determine the extent to which poison center triage guidelines influence healthcare facility referral rates for acute, unintentional acetaminophen-only poisoning and acute, unintentional adult formulation iron poisoning. Managers of US poison centers were interviewed by telephone to determine their center's triage threshold value (mg/kg) for acute iron and acute acetaminophen poisoning in 1997. Triage threshold values and healthcare facility referral rates were fit to a univariate logistic regression model for acetaminophen and iron using maximum likelihood estimation. Triage threshold values ranged from 120-201 mg/kg (acetaminophen) and 16-61 mg/kg (iron). Referral rates ranged from 3.1% to 24% (acetaminophen) and 3.7% to 46.7% (iron). There was a statistically significant inverse relationship between the triage value and the referral rate for acetaminophen (p < 0.001) and iron (p = 0.0013). The model explained 31.7% of the referral variation for acetaminophen but only 4.1% of the variation for iron. There is great variability in poison center triage values and referral rates for iron and acetaminophen poisoning. Guidelines can account for a meaningful proportion of referral variation. Their influence appears to be substance dependent. These data suggest that efforts to determine and utilize the highest, safe, triage threshold value could substantially decrease healthcare costs for poisonings as long as patient medical outcomes are not compromised.
Finkenstaedt, Tim; Morsbach, Fabian; Calcagni, Maurizio; Vich, Magdalena; Pfirrmann, Christian W A; Alkadhi, Hatem; Runge, Val M; Andreisek, Gustav; Guggenberger, Roman
2014-08-01
The aim of this study was to compare image quality and extent of artifacts from scaphoid fracture fixation screws using different computed tomography (CT) modalities and radiation dose protocols. Imaging of 6 cadaveric wrists with artificial scaphoid fractures and different fixation screws was performed in 2 screw positions (45° and 90° orientation in relation to the x/y-axis) using multidetector CT (MDCT) and 2 flat-panel CT modalities, C-arm flat-panel CT (FPCT) and cone-beam CT (CBCT), the latter 2 with low and standard radiation dose protocols. Mean cartilage attenuation and metal artifact-induced absolute Hounsfield unit changes (= artifact extent) were measured. Two independent radiologists evaluated different image quality criteria using a 5-point Likert-scale. Interreader agreements (Cohen κ) were calculated. Mean absolute Hounsfield unit changes and quality ratings were compared using Friedman and Wilcoxon signed-rank tests. Artifact extent was significantly smaller for MDCT and standard-dose FPCT compared with CBCT low- and standard-dose acquisitions (all P < 0.05). No significant differences in artifact extent among different screw types and scanning positions were noted (P > 0.05). Both MDCT and FPCT standard-dose protocols showed equal ratings for screw bone interface, fracture line, and trabecular bone evaluation (P = 0.06, 0.2, and 0.2, respectively) and performed significantly better than FPCT low- and CBCT low- and standard-dose acquisitions (all P < 0.05). Good interreader agreement was found for image quality comparisons (Cohen κ = 0.76-0.78). Both MDCT and FPCT standard-dose acquisition showed comparatively less metal-induced artifacts and better overall image quality compared with FPCT low-dose and both CBCT acquisitions. Flat-panel CT may provide sufficient image quality to serve as a versatile CT alternative for postoperative imaging of internally fixated wrist fractures.
Nagayama, Yasunori; Nakaura, Takeshi; Tsuji, Akinori; Urata, Joji; Furusawa, Mitsuhiro; Yuki, Hideaki; Hirarta, Kenichiro; Kidoh, Masafumi; Oda, Seitaro; Utsunomiya, Daisuke; Yamashita, Yasuyuki
2017-07-01
To retrospectively evaluate the image quality and radiation dose of 100-kVp scans with sinogram-affirmed iterative reconstruction (IR) for unenhanced head CT in adolescents. Sixty-nine patients aged 12-17 years underwent head CT under 120- (n = 34) or 100-kVp (n = 35) protocols. The 120-kVp images were reconstructed with filtered back-projection (FBP), 100-kVp images with FBP (100-kVp-F) and sinogram-affirmed IR (100-kVp-S). We compared the effective dose (ED), grey-white matter (GM-WM) contrast, image noise, and contrast-to-noise ratio (CNR) between protocols in supratentorial (ST) and posterior fossa (PS). We also assessed GM-WM contrast, image noise, sharpness, artifacts, and overall image quality on a four-point scale. ED was 46% lower with 100- than 120-kVp (p < 0.001). GM-WM contrast was higher, and image noise was lower, on 100-kVp-S than 120-kVp at ST (p < 0.001). CNR of 100-kVp-S was higher than of 120-kVp (p < 0.001). GM-WM contrast of 100-kVp-S was subjectively rated as better than of 120-kVp (p < 0.001). There were no significant differences in the other criteria between 100-kVp-S and 120-kVp (p = 0.072-0.966). The 100-kVp with sinogram-affirmed IR facilitated dramatic radiation reduction and better GM-WM contrast without increasing image noise in adolescent head CT. • 100-kVp head CT provides 46% radiation dose reduction compared with 120-kVp. • 100-kVp scanning improves subjective and objective GM-WM contrast. • Sinogram-affirmed IR decreases head CT image noise, especially in supratentorial region. • 100-kVp protocol with sinogram-affirmed IR is suited for adolescent head CT.
NASA Astrophysics Data System (ADS)
Lavoie, Lindsey K.
The technology of computed tomography (CT) imaging has soared over the last decade with the use of multi-detector CT (MDCT) scanners that are capable of performing studies in a matter of seconds. While the diagnostic information obtained from MDCT imaging is extremely valuable, it is important to ensure that the radiation doses resulting from these studies are at acceptably safe levels. This research project focused on the measurement of organ doses resulting from modern MDCT scanners. A commercially-available dosimetry system was used to measure organ doses. Small dosimeters made of optically-stimulated luminescent (OSL) material were analyzed with a portable OSL reader. Detailed verification of this system was performed. Characteristics studied include energy, scatter, and angular responses; dose linearity, ability to erase the exposed dose and ability to reuse dosimeters multiple times. The results of this verification process were positive. While small correction factors needed to be applied to the dose reported by the OSL reader, these factors were small and expected. Physical, tomographic pediatric and adult phantoms were used to measure organ doses. These phantoms were developed from CT images and are composed of tissue-equivalent materials. Because the adult phantom is comprised of numerous segments, dosimeters were placed in the phantom at several organ locations, and doses to select organs were measured using three clinical protocols: pediatric craniosynostosis, adult brain perfusion and adult cardiac CT angiography (CTA). A wide-beam, 320-slice, volumetric CT scanner and a 64-slice, MDCT scanner were used for organ dose measurements. Doses ranged from 1 to 26 mGy for the pediatric protocol, 1 to 1241 mGy for the brain perfusion protocol, and 2-100 mGy for the cardiac protocol. In most cases, the doses measured on the 64-slice scanner were higher than those on the 320-slice scanner. A methodology to measure organ doses with OSL dosimeters received from CT imaging has been presented. These measurements are especially important in keeping with the ALARA (as low as reasonably achievable) principle. While diagnostic information from CT imaging is valuable and necessary, the dose to patients is always a consideration. This methodology aids in this important task. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)
Can contrast media increase organ doses in CT examinations? A clinical study.
Amato, Ernesto; Salamone, Ignazio; Naso, Serena; Bottari, Antonio; Gaeta, Michele; Blandino, Alfredo
2013-06-01
The purpose of this article is to quantify the CT radiation dose increment in five organs resulting from the administration of iodinated contrast medium. Forty consecutive patients who underwent both un-enhanced and contrast-enhanced thoracoabdominal CT were included in our retrospective study. The dose increase between CT before and after contrast agent administration was evaluated in the portal phase for the thyroid, liver, spleen, pancreas, and kidneys by applying a previously validated method. An increase in radiation dose was noted in all organs studied. Average dose increments were 19% for liver, 71% for kidneys, 33% for spleen and pancreas, and 41% for thyroid. Kidneys exhibited the maximum dose increment, whereas the pancreas showed the widest variance because of the differences in fibro-fatty involution. Finally, thyroids with high attenuation values on unenhanced CT showed a lower Hounsfield unit increase and, thus, a smaller increment in the dose. Our study showed an increase in radiation dose in several parenchymatous tissues on contrast-enhanced CT. Our method allowed us to evaluate the dose increase from the change in attenuation measured in Hounsfield units. Because diagnostic protocols require multiple acquisitions after the contrast agent administration, such a dose increase should be considered when optimizing these protocols.
Lee, Ho-Joon; Kim, Jinna; Kim, Ki Wook; Lee, Seung-Koo; Yoon, Jin Sook
2018-06-23
To evaluate the clinical feasibility of low-dose orbital CT with a knowledge-based iterative model reconstruction (IMR) algorithm for evaluating Graves' orbitopathy. Low-dose orbital CT was performed with a CTDI vol of 4.4 mGy. In 12 patients for whom prior or subsequent non-low-dose orbital CT data obtained within 12 months were available, background noise, SNR, and CNR were compared for images generated using filtered back projection (FBP), hybrid iterative reconstruction (iDose 4 ), and IMR and non-low-dose CT images. Comparison of clinically relevant measurements for Graves' orbitopathy, such as rectus muscle thickness and retrobulbar fat area, was performed in a subset of 6 patients who underwent CT for causes other than Graves' orbitopathy, by using the Wilcoxon signed-rank test. The lens dose estimated from skin dosimetry on a phantom was 4.13 mGy, which was on average 59.34% lower than that of the non-low-dose protocols. Image quality in terms of background noise, SNR, and CNR was the best for IMR, followed by non-low-dose CT, iDose 4 , and FBP, in descending order. A comparison of clinically relevant measurements revealed no significant difference in the retrobulbar fat area and the inferior and medial rectus muscle thicknesses between the low-dose and non-low-dose CT images. Low-dose CT with IMR may be performed without significantly affecting the measurement of prognostic parameters for Graves' orbitopathy while lowering the lens dose and image noise. Copyright © 2018 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Trattner, Sigal; Cheng, Bin; Pieniazek, Radoslaw L.
2014-04-15
Purpose: Effective dose (ED) is a widely used metric for comparing ionizing radiation burden between different imaging modalities, scanners, and scan protocols. In computed tomography (CT), ED can be estimated by performing scans on an anthropomorphic phantom in which metal-oxide-semiconductor field-effect transistor (MOSFET) solid-state dosimeters have been placed to enable organ dose measurements. Here a statistical framework is established to determine the sample size (number of scans) needed for estimating ED to a desired precision and confidence, for a particular scanner and scan protocol, subject to practical limitations. Methods: The statistical scheme involves solving equations which minimize the sample sizemore » required for estimating ED to desired precision and confidence. It is subject to a constrained variation of the estimated ED and solved using the Lagrange multiplier method. The scheme incorporates measurement variation introduced both by MOSFET calibration, and by variation in MOSFET readings between repeated CT scans. Sample size requirements are illustrated on cardiac, chest, and abdomen–pelvis CT scans performed on a 320-row scanner and chest CT performed on a 16-row scanner. Results: Sample sizes for estimating ED vary considerably between scanners and protocols. Sample size increases as the required precision or confidence is higher and also as the anticipated ED is lower. For example, for a helical chest protocol, for 95% confidence and 5% precision for the ED, 30 measurements are required on the 320-row scanner and 11 on the 16-row scanner when the anticipated ED is 4 mSv; these sample sizes are 5 and 2, respectively, when the anticipated ED is 10 mSv. Conclusions: Applying the suggested scheme, it was found that even at modest sample sizes, it is feasible to estimate ED with high precision and a high degree of confidence. As CT technology develops enabling ED to be lowered, more MOSFET measurements are needed to estimate ED with the same precision and confidence.« less
Ippolito, Davide; Fior, Davide; Franzesi, Cammillo Talei; Riva, Luca; Casiraghi, Alessandra; Sironi, Sandro
2017-12-01
Effective radiation dose in coronary CT angiography (CTCA) for coronary artery bypass graft (CABG) evaluation is remarkably high because of long scan lengths. Prospective electrocardiographic gating with iterative reconstruction can reduce effective radiation dose. To evaluate the diagnostic performance of low-kV CT angiography protocol with prospective ecg-gating technique and iterative reconstruction (IR) algorithm in follow-up of CABG patients compared with standard retrospective protocol. Seventy-four non-obese patients with known coronary disease treated with artery bypass grafting were prospectively enrolled. All the patients underwent 256 MDCT (Brilliance iCT, Philips) CTCA using low-dose protocol (100 kV; 800 mAs; rotation time: 0.275 s) combined with prospective ECG-triggering acquisition and fourth-generation IR technique (iDose 4 ; Philips); all the lengths of the bypass graft were included in the evaluation. A control group of 42 similar patients was evaluated with a standard retrospective ECG-gated CTCA (100 kV; 800 mAs).On both CT examinations, ROIs were placed to calculate standard deviation of pixel values and intra-vessel density. Diagnostic quality was also evaluated using a 4-point quality scale. Despite the statistically significant reduction of radiation dose evaluated with DLP (study group mean DLP: 274 mGy cm; control group mean DLP: 1224 mGy cm; P value < 0.001). No statistical differences were found between PGA group and RGH group regarding intra-vessel density absolute values and SNR. Qualitative analysis, evaluated by two radiologists in "double blind", did not reveal any significant difference in diagnostic quality of the two groups. The development of high-speed MDCT scans combined with modern IR allows an accurate evaluation of CABG with prospective ECG-gating protocols in a single breath hold, obtaining a significant reduction in radiation dose.
Trattner, Sigal; Cheng, Bin; Pieniazek, Radoslaw L.; Hoffmann, Udo; Douglas, Pamela S.; Einstein, Andrew J.
2014-01-01
Purpose: Effective dose (ED) is a widely used metric for comparing ionizing radiation burden between different imaging modalities, scanners, and scan protocols. In computed tomography (CT), ED can be estimated by performing scans on an anthropomorphic phantom in which metal-oxide-semiconductor field-effect transistor (MOSFET) solid-state dosimeters have been placed to enable organ dose measurements. Here a statistical framework is established to determine the sample size (number of scans) needed for estimating ED to a desired precision and confidence, for a particular scanner and scan protocol, subject to practical limitations. Methods: The statistical scheme involves solving equations which minimize the sample size required for estimating ED to desired precision and confidence. It is subject to a constrained variation of the estimated ED and solved using the Lagrange multiplier method. The scheme incorporates measurement variation introduced both by MOSFET calibration, and by variation in MOSFET readings between repeated CT scans. Sample size requirements are illustrated on cardiac, chest, and abdomen–pelvis CT scans performed on a 320-row scanner and chest CT performed on a 16-row scanner. Results: Sample sizes for estimating ED vary considerably between scanners and protocols. Sample size increases as the required precision or confidence is higher and also as the anticipated ED is lower. For example, for a helical chest protocol, for 95% confidence and 5% precision for the ED, 30 measurements are required on the 320-row scanner and 11 on the 16-row scanner when the anticipated ED is 4 mSv; these sample sizes are 5 and 2, respectively, when the anticipated ED is 10 mSv. Conclusions: Applying the suggested scheme, it was found that even at modest sample sizes, it is feasible to estimate ED with high precision and a high degree of confidence. As CT technology develops enabling ED to be lowered, more MOSFET measurements are needed to estimate ED with the same precision and confidence. PMID:24694150
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, D; Neylon, J; Dou, T
Purpose: A recently proposed 4D-CT protocol uses deformable registration of free-breathing fast-helical CT scans to generate a breathing motion model. In order to allow accurate registration, free-breathing images are required to be free of doubling-artifacts, which arise when tissue motion is greater than scan speed. This work identifies the minimum scanner parameters required to successfully generate free-breathing fast-helical scans without doubling-artifacts. Methods: 10 patients were imaged under free breathing conditions 25 times in alternating directions with a 64-slice CT scanner using a low dose fast helical protocol. A high temporal resolution (0.1s) 4D-CT was generated using a patient specific motionmore » model and patient breathing waveforms, and used as the input for a scanner simulation. Forward projections were calculated using helical cone-beam geometry (800 projections per rotation) and a GPU accelerated reconstruction algorithm was implemented. Various CT scanner detector widths and rotation times were simulated, and verified using a motion phantom. Doubling-artifacts were quantified in patient images using structural similarity maps to determine the similarity between axial slices. Results: Increasing amounts of doubling-artifacts were observed with increasing rotation times > 0.2s for 16×1mm slice scan geometry. No significant increase in doubling artifacts was observed for 64×1mm slice scan geometry up to 1.0s rotation time although blurring artifacts were observed >0.6s. Using a 16×1mm slice scan geometry, a rotation time of less than 0.3s (53mm/s scan speed) would be required to produce images of similar quality to a 64×1mm slice scan geometry. Conclusion: The current generation of 16 slice CT scanners, which are present in most Radiation Oncology departments, are not capable of generating free-breathing sorting-artifact-free images in the majority of patients. The next generation of CT scanners should be capable of at least 53mm/s scan speed in order to use a fast-helical 4D-CT protocol to generate a motion-artifact free 4D-CT. NIH R01CA096679.« less
Pediatric disaster triage education and skills assessment: a coalition approach.
Kenningham, Katherine; Koelemay, Kathryn; King, Mary A
2014-01-01
This study aims to 1) demonstrate one method of pediatric disaster preparedness education using a regional disaster coalition organized workshop and 2) evaluate factors reflecting the greatest shortfall in pediatric mass casualty incident (MCI) triage skills in a varied population of medical providers in King County, WA. Educational intervention and cross-sectional survey. Pediatric disaster preparedness conference created de novo and offered by the King County Healthcare Coalition, with didactic sessions and workshops including a scored mock pediatric MCI triage. Ninety-eight providers from throughout the King County, WA, region selected by their own institutions following invitation to participate, with 88 completing exit surveys. Didactic lectures regarding pediatric MCI triage followed by scored exercises. Mock triage scores were analyzed and compared according to participant characteristics and workplace environment. A half-day regional pediatric disaster preparedness educational conference convened in September 2011 by the King County Healthcare Coalition in partnership with regional pediatric experts was so effective and well-received that it has been rescheduled yearly (2012 and 2013) and has expanded to three Washington State venues sponsored by the Washington State Department of Health. Emergency department (ED) or intensive care unit (ICU) employment and regular exposure to pediatric patients best predicted higher mock pediatric MCI triage scores (ED/ICU 80 percent vs non-ED/ICU 73 percent, p = 0.026; regular pediatric exposure 80 percent vs less exposure 77 percent, p = 0.038, respectively). Pediatric Advanced Life Support training was not found to be associated with improved triage performance, and mock patients whose injuries were not immediately life threatening tended to be over-triaged (observed trend). A regional coalition can effectively organize member hospitals and provide education for focused populations using specialty experts such as pediatricians. Providers working in higher acuity environments and those with regular pediatric patient exposure perform better mock pediatric MCI triage than their counterparts after just-in-time training. Pediatric MCI patients with less than life-threatening injuries tended to be over-triaged.
Decision analytic model exploring the cost and cost-offset implications of street triage.
Heslin, Margaret; Callaghan, Lynne; Packwood, Martin; Badu, Vincent; Byford, Sarah
2016-02-11
To determine if street triage is effective at reducing the total number of people with mental health needs detained under section 136, and is associated with cost savings compared to usual police response. Routine data from a 6-month period in the year before and after the implementation of a street triage scheme were used to explore detentions under section 136, and to populate a decision analytic model to explore the impact of street triage on the cost to the NHS and the criminal justice sector of supporting people with a mental health need. A predefined area of Sussex, South East England, UK. All people who were detained under section 136 within the predefined area or had contact with the street triage team. The street triage model used here was based on a psychiatric nurse attending incidents with a police constable. The primary outcome was change in the total number of detentions under section 136 between the before and after periods assessed. Secondary analysis focused on whether the additional costs of street triage were offset by cost savings as a result of changes in detentions under section 136. Detentions under section 136 in the street triage period were significantly lower than in the usual response period (118 vs 194 incidents, respectively; χ(2) (1df) 18.542, p<0.001). Total NHS and criminal justice costs were estimated to be £1043 in the street triage period compared to £1077 in the usual response period. Investment in street triage was offset by savings as a result of reduced detentions under section 136, particularly detentions in custody. Data available did not include assessment of patient outcomes, so a full economic evaluation was not possible. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Huibers, Linda; Moth, Grete; Carlsen, Anders H; Christensen, Morten B; Vedsted, Peter
2016-01-01
Background In the UK, telephone triage in out-of-hours primary care is mostly managed by nurses, whereas GPs perform triage in Denmark. Aim To describe telephone contacts triaged to face-to-face contacts, GP-assessed relevance, and factors associated with triage to face-to-face contact. Design and setting A prospective observational study in Danish out-of-hours primary care, conducted from June 2010 to May 2011. Method Information on patients was collected from the electronic patient administration system and GPs completed electronic questionnaires about the contacts. The GPs conducting the face-to-face contacts assessed relevance of the triage to face-to-face contacts. The authors performed binomial regression analyses, calculating relative risk (RR) and 95% confidence intervals. Results In total, 59.2% of calls ended with a telephone consultation. Factors associated with triage to a face-to-face contact were: patient age >40 years (40–64: RR = 1.13; >64: RR = 1.34), persisting problem for 12–24 hours (RR = 1.15), severe problem (RR = 2.60), potentially severe problem (RR = 5.81), and non-severe problem (RR = 2.23). Face-to-face contacts were assessed as irrelevant for 12.7% of clinic consultations and 11.7% of home visits. A statistically significantly higher risk of irrelevant face-to-face contact was found for a persisting problem of >24 hours (RR = 1.25), contact on weekday nights (RR = 1.25), and contact <2 hours before the patient’s own GP’s opening time (RR = 1.80). Conclusion Around 12% of all face-to-face consultations in the study are assessed as irrelevant by GP colleagues, suggesting that GP triage is efficient. Knowledge of the factors influencing triage can provide better education for GPs, but future studies are needed to investigate other quality aspects of GP telephone triage. PMID:27432608
WE-D-207-03: CT Protocols for Screening and the ACR Designated Lung Screening Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
McNitt-Gray, M.
2015-06-15
In the United States, Lung Cancer is responsible for more cancer deaths than the next four cancers combined. In addition, the 5 year survival rate for lung cancer patients has not improved over the past 40 to 50 years. To combat this deadly disease, in 2002 the National Cancer Institute launched a very large Randomized Control Trial called the National Lung Screening Trial (NLST). This trial would randomize subjects who had substantial risk of lung cancer (due to age and smoking history) into either a Chest X-ray arm or a low dose CT arm. In November 2010, the National Cancermore » Institute announced that the NLST had demonstrated 20% fewer lung cancer deaths among those who were screened with low-dose CT than with chest X-ray. In December 2013, the US Preventive Services Task Force recommended the use of Lung Cancer Screening using low dose CT and a little over a year later (Feb. 2015), CMS announced that Medicare would also cover Lung Cancer Screening using low dose CT. Thus private and public insurers are required to provide Lung Cancer Screening programs using CT to the appropriate population(s). The purpose of this Symposium is to inform medical physicists and prepare them to support the implementation of Lung Screening programs. This Symposium will focus on the clinical aspects of lung cancer screening, requirements of a screening registry for systematically capturing and tracking screening patients and results (such as required Medicare data elements) as well as the role of the medical physicist in screening programs, including the development of low dose CT screening protocols. Learning Objectives: To understand the clinical basis and clinical components of a lung cancer screening program, including eligibility criteria and other requirements. To understand the data collection requirements, workflow, and informatics infrastructure needed to support the tracking and reporting components of a screening program. To understand the role of the medical physicist in implementing Lung Cancer Screening protocols for CT, including utilizing resources such as the AAPM Protocols and the ACR Designated Lung Screening Center program. UCLA Department of Radiology has an Institutional research agreement with Siemens Healthcare; Dr. McNitt-Gray has been a recipient of Research Support from Siemens Healthcare in the past. Dr. Aberle has been a Member of Advisory Boards for the LUNGevity Foundation (2011-present) and Siemens Medical Solutions. (2013)« less
Working with Manchester triage -- job satisfaction in nursing.
Forsgren, Susanne; Forsman, Berit; Carlström, Eric D
2009-10-01
This article covers nurses' job satisfaction during triage at emergency departments in Western Sweden. Data was collected from 74 triage nurses using a questionnaire containing 37 short form open questions. The answers were analyzed descriptively and by measuring the covariance. The open questions were analyzed by content analysis. The results showed a high degree of job satisfaction (88%). Triage as a method, the interesting nature of the work, and a certain freedom in connection with the triage tasks contributed to job satisfaction (R(2) = 0.40). The nurses found their work interesting and stimulating, although some reported job dissatisfaction due to a heavy workload and lack of competence. Most of the nurses thought that Manchester triage (MTS) was a clear and straightforward method but in need of development. The rational modelling structure by which the triage method is constructed is unable to distinguish all the parameters that an experienced nurse takes into account. When the model is allowed to take precedence over experience, it can be of hindrance and contribute to certain estimates not corresponding with the patient's needs. The participants requested regular exercises solving and discussing patient scenarios. They also wanted to participate on a regular basis in the development of the instrument.
Protocolized Treatment Is Associated With Decreased Organ Dysfunction in Pediatric Severe Sepsis.
Balamuth, Fran; Weiss, Scott L; Fitzgerald, Julie C; Hayes, Katie; Centkowski, Sierra; Chilutti, Marianne; Grundmeier, Robert W; Lavelle, Jane; Alpern, Elizabeth R
2016-09-01
To determine whether treatment with a protocolized sepsis guideline in the emergency department was associated with a lower burden of organ dysfunction by hospital day 2 compared to nonprotocolized usual care in pediatric patients with severe sepsis. Retrospective cohort study. Tertiary care children's hospital from January 1, 2012, to March 31, 2014. Patients older than 56 days old and younger than 18 years old with international consensus defined severe sepsis and who required PICU admission within 24 hours of emergency department arrival were included. The exposure was the use of a protocolized emergency department sepsis guideline. The primary outcome was complete resolution of organ dysfunction by hospital day 2. One hundred eighty nine subjects were identified during the study period. Of these, 121 (64%) were treated with the protocolized emergency department guideline and 68 were not. There were no significant differences between the groups in age, sex, race, number of comorbid conditions, emergency department triage level, or organ dysfunction on arrival to the emergency department. Patients treated with protocolized emergency department care were more likely to be free of organ dysfunction on hospital day 2 after controlling for sex, comorbid condition, indwelling central venous catheter, Pediatric Index of Mortality-2 score, and timing of antibiotics and IV fluids (adjusted odds ratio, 4.2; 95% CI, 1.7-10.4). Use of a protocolized emergency department sepsis guideline was independently associated with resolution of organ dysfunction by hospital day 2 compared to nonprotocolized usual care. These data indicate that morbidity outcomes in children can be improved with the use of protocolized care.
Ferraz, Eduardo Gomes; Andrade, Lucio Costa Safira; dos Santos, Aline Rode; Torregrossa, Vinicius Rabelo; Rubira-Bullen, Izabel Regina Fischer; Sarmento, Viviane Almeida
2013-12-01
The aim of this study was to evaluate the accuracy of virtual three-dimensional (3D) reconstructions of human dry mandibles, produced from two segmentation protocols ("outline only" and "all-boundary lines"). Twenty virtual three-dimensional (3D) images were built from computed tomography exam (CT) of 10 dry mandibles, in which linear measurements between anatomical landmarks were obtained and compared to an error probability of 5 %. The results showed no statistically significant difference among the dry mandibles and the virtual 3D reconstructions produced from segmentation protocols tested (p = 0,24). During the designing of a virtual 3D reconstruction, both "outline only" and "all-boundary lines" segmentation protocols can be used. Virtual processing of CT images is the most complex stage during the manufacture of the biomodel. Establishing a better protocol during this phase allows the construction of a biomodel with characteristics that are closer to the original anatomical structures. This is essential to ensure a correct preoperative planning and a suitable treatment.
Multi-modal anatomical optical coherence tomography and CT for in vivo dynamic upper airway imaging
NASA Astrophysics Data System (ADS)
Balakrishnan, Santosh; Bu, Ruofei; Price, Hillel; Zdanski, Carlton; Oldenburg, Amy L.
2017-02-01
We describe a novel, multi-modal imaging protocol for validating quantitative dynamic airway imaging performed using anatomical Optical Coherence Tomography (aOCT). The aOCT system consists of a catheter-based aOCT probe that is deployed via a bronchoscope, while a programmable ventilator is used to control airway pressure. This setup is employed on the bed of a Siemens Biograph CT system capable of performing respiratory-gated acquisitions. In this arrangement the position of the aOCT catheter may be visualized with CT to aid in co-registration. Utilizing this setup we investigate multiple respiratory pressure parameters with aOCT, and respiratory-gated CT, on both ex vivo porcine trachea and live, anesthetized pigs. This acquisition protocol has enabled real-time measurement of airway deformation with simultaneous measurement of pressure under physiologically relevant static and dynamic conditions- inspiratory peak or peak positive airway pressures of 10-40 cm H2O, and 20-30 breaths per minute for dynamic studies. We subsequently compare the airway cross sectional areas (CSA) obtained from aOCT and CT, including the change in CSA at different stages of the breathing cycle for dynamic studies, and the CSA at different peak positive airway pressures for static studies. This approach has allowed us to improve our acquisition methodology and to validate aOCT measurements of the dynamic airway for the first time. We believe that this protocol will prove invaluable for aOCT system development and greatly facilitate translation of OCT systems for airway imaging into the clinical setting.
A consensus-based gold standard for the evaluation of mass casualty triage systems.
Lerner, E Brooke; McKee, Courtney H; Cady, Charles E; Cone, David C; Colella, M Riccardo; Cooper, Arthur; Coule, Phillip L; Lairet, Julio R; Liu, J Marc; Pirrallo, Ronald G; Sasser, Scott M; Schwartz, Richard; Shepherd, Greene; Swienton, Raymond E
2015-01-01
Accuracy and effectiveness analyses of mass casualty triage systems are limited because there are no gold standard definitions for each of the triage categories. Until there is agreement on which patients should be identified by each triage category, it will be impossible to calculate sensitivity and specificity or to compare accuracy between triage systems. To develop a consensus-based, functional gold standard definition for each mass casualty triage category. National experts were recruited through the lead investigators' contacts and their suggested contacts. Key informant interviews were conducted to develop a list of potential criteria for defining each triage category. Panelists were interviewed in order of their availability until redundancy of themes was achieved. Panelists were blinded to each other's responses during the interviews. A modified Delphi survey was developed with the potential criteria identified during the interview and delivered to all recruited experts. In the early rounds, panelists could add, remove, or modify criteria. In the final rounds edits were made to the criteria until at least 80% agreement was achieved. Thirteen national and local experts were recruited to participate in the project. Six interviews were conducted. Three rounds of voting were performed, with 12 panelists participating in the first round, 12 in the second round, and 13 in the third round. After the first two rounds, the criteria were modified according to respondent suggestions. In the final round, over 90% agreement was achieved for all but one criterion. A single e-mail vote was conducted on edits to the final criterion and consensus was achieved. A consensus-based, functional gold standard definition for each mass casualty triage category was developed. These gold standard definitions can be used to evaluate the accuracy of mass casualty triage systems after an actual incident, during training, or for research.
2 Major incident triage and the implementation of a new triage tool, the MPTT-24.
Vassallo, James; Smith, Jason
2017-12-01
Over the last decade, a number of European cities including London, have witnessed high profile terrorist attacks resulting in major incidents with large numbers of casualties. Triage, the process of categorising casualties on the basis of their clinical acuity, is a key principle in the effective management of major incidents.The Modified Physiological Triage Tool (MPTT) is a recently developed primary triage tool which in comparison to existing triage tools, including the 2013 UK NARU Sieve, demonstrates the greatest sensitivity at predicting need for life-saving intervention (LSI) within both military and civilian populations.To improve the applicability and usability of the MPTT we increased the upper respiratory rate threshold to 24 breaths per minute (MPTT-24), to make it divisible by four, and included an assessment of external catastrophic haemorrhage. The aim of this study was to conduct a feasibility analysis of the proposed MPTT-24 (figure 1).emermed;34/12/A860-b/F1F1F1Figure 1MPTT-24 METHODS: A retrospective review of the Joint Theatre Trauma Registry (JTTR) and Trauma Audit Research Network (TARN) databases was performed for all adult ( > 18 years) patients presenting between 2006-2013 (JTTR) and 2014 (TARN). Patients were defined as priority one (P1) if they had received one or more life-saving interventions.Using first recorded hospital physiology, patients were categorised as P1 or not-P1 by existing triage tools and both MPTT and MPTT-24. Performance characteristics were evaluated using sensitivity, specificity, under and over-triage with a McNemar test to determine statistical significance. Basic study characteristics are shown in Table 1. Both the MPTT and MPTT-24 outperformed all existing triage methods with a statistically significant (p<0.001) absolute reduction of between 25.5%-29.5% in under-triage when compared to existing UK civilian methods (NARU Sieve). In both populations the MPTT-24 demonstrated an absolute reduction in sensitivity with an increase in specificity when compared to the MPTT. A statistically significant difference was observed between the MPTT and MPTT-24 in the way they categorised TARN and JTTR cases as P1 (p<0.001).emermed;34/12/A860-b/T1F2T1Table 1Study characteristicsemermed;34/12/A860-b/T2F3T2Table 2Performance analysis CONCLUSION: Existing UK methods of primary major incident triage, including the NARU Sieve, are not fit for purpose, with unacceptably high rates of under-triage. When compared to the MPTT, the MPTT-24 allows for a more rapid triage assessment and continues to outperform existing triage tools at predicting need for life-saving intervention. Its use should be considered in civilian and military major incidents. © 2017, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Initial investigation into lower-cost CT for resource limited regions of the world
NASA Astrophysics Data System (ADS)
Dobbins, James T., III; Wells, Jered R.; Segars, W. Paul; Li, Christina M.; Kigongo, Christopher J. N.
2010-04-01
This paper describes an initial investigation into means for producing lower-cost CT scanners for resource limited regions of the world. In regions such as sub-Saharan Africa, intermediate level medical facilities serving millions have no CT machines, and lack the imaging resources necessary to determine whether certain patients would benefit from being transferred to a hospital in a larger city for further diagnostic workup or treatment. Low-cost CT scanners would potentially be of immense help to the healthcare system in such regions. Such scanners would not produce state-of-theart image quality, but rather would be intended primarily for triaging purposes to determine the patients who would benefit from transfer to larger hospitals. The lower-cost scanner investigated here consists of a fixed digital radiography system and a rotating patient stage. This paper describes initial experiments to determine if such a configuration is feasible. Experiments were conducted using (1) x-ray image acquisition, a physical anthropomorphic chest phantom, and a flat-panel detector system, and (2) a computer-simulated XCAT chest phantom. Both the physical phantom and simulated phantom produced excellent image quality reconstructions when the phantom was perfectly aligned during acquisition, but artifacts were noted when the phantom was displaced to simulate patient motion. An algorithm was developed to correct for motion of the phantom and demonstrated success in correcting for 5-mm motion during 360-degree acquisition of images. These experiments demonstrated feasibility for this approach, but additional work is required to determine the exact limitations produced by patient motion.
Optimization of oncological {sup 18}F-FDG PET/CT imaging based on a multiparameter analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Menezes, Vinicius O., E-mail: vinicius@radtec.com.br; Machado, Marcos A. D.; Queiroz, Cleiton C.
2016-02-15
Purpose: This paper describes a method to achieve consistent clinical image quality in {sup 18}F-FDG scans accounting for patient habitus, dose regimen, image acquisition, and processing techniques. Methods: Oncological PET/CT scan data for 58 subjects were evaluated retrospectively to derive analytical curves that predict image quality. Patient noise equivalent count rate and coefficient of variation (CV) were used as metrics in their analysis. Optimized acquisition protocols were identified and prospectively applied to 179 subjects. Results: The adoption of different schemes for three body mass ranges (<60 kg, 60–90 kg, >90 kg) allows improved image quality with both point spread functionmore » and ordered-subsets expectation maximization-3D reconstruction methods. The application of this methodology showed that CV improved significantly (p < 0.0001) in clinical practice. Conclusions: Consistent oncological PET/CT image quality on a high-performance scanner was achieved from an analysis of the relations existing between dose regimen, patient habitus, acquisition, and processing techniques. The proposed methodology may be used by PET/CT centers to develop protocols to standardize PET/CT imaging procedures and achieve better patient management and cost-effective operations.« less
Maroules, Christopher D; Blaha, Michael J; El-Haddad, Mohamed A; Ferencik, Maros; Cury, Ricardo C
2013-01-01
Coronary CT angiography is an effective, evidence-based strategy for evaluating acute chest pain in the emergency department for patients at low-to-intermediate risk of acute coronary syndrome. Recent multicenter trials have reported that coronary CT angiography is safe, reduces time to diagnosis, facilitates discharge, and may lower overall cost compared with routine care. Herein, we provide a 10-step approach for establishing a successful coronary CT angiography program in the emergency department. The importance of strategic planning and multidisciplinary collaboration is emphasized. Patient selection and preparation guidelines for coronary CT angiography are reviewed with straightforward protocols that can be adapted and modified to clinical sites, depending on available cardiac imaging capabilities. Technical parameters and patient-specific modifications are also highlighted to maximize the likelihood of diagnostic quality examinations. Practical suggestions for quality control, process monitoring, and standardized reporting are reviewed. Finally, the role of a "triple rule-out" protocol is featured in the context of acute chest pain evaluation in the emergency department. Copyright © 2013 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thor, Daniel; Brismar, Torkel B., E-mail: torkel.brismar@gmail.com; Fischer, Michael A.
Purpose: To evaluate the potential of low tube voltage dual source (DS) single energy (SE) and dual energy (DE) computed tomography (CT) to reduce contrast media (CM) dose in adult abdominal examinations of various sizes while maintaining soft tissue and iodine contrast-to-noise ratio (CNR). Methods: Four abdominal phantoms simulating a body mass index of 16 to 35 kg/m{sup 2} with four inserted syringes of 0, 2, 4, and 8 mgI/ml CM were scanned using a 64-slice DS-CT scanner. Six imaging protocols were used; one single source (SS) reference protocol (120 kV, 180 reference mAs), four low kV SE protocols (70more » and 80 kV using both SS and DS), and one DE protocol at 80/140 kV. Potential CM reduction with unchanged CNRs relative to the 120 kV protocol was calculated along with the corresponding increase in radiation dose. Results: The potential contrast media reductions were determined to be approximately 53% for DS 70 kV, 51% for SS 70 kV, 44% for DS 80 kV, 40% for SS 80 kV, and 20% for DE (all differences were significant, P < 0.05). Constant CNR could be achieved by using DS 70 kV for small to medium phantom sizes (16–26 kg/m{sup 2}) and for all sizes (16–35 kg/m{sup 2}) when using DS 80 kV and DE. Corresponding radiation doses increased by 60%–107%, 23%–83%, and 6%–12%, respectively. Conclusions: DS single energy CT can be used to reduce CM dose by 44%–53% with maintained CNR in adult abdominal examinations at the cost of an increased radiation dose. DS dual-energy CT allows reduction of CM dose by 20% at similar radiation dose as compared to a standard 120 kV single source.« less
Evaluation of organ doses in CT examinations with an infant anthropomorphic phantom.
Fujii, K; Akahane, K; Miyazaki, O; Horiuchi, T; Shimada, A; Nagmatsu, H; Yamauchi, M; Yamauchi-Kawaura, C; Kawasaki, T
2011-09-01
The aim of this study is to evaluate organ doses in infant CT examinations with multi-detector row CT scanners. Radiation doses were measured with radiophotoluminescence glass dosemeters set in various organ positions within a 1-y-old child anthropomorphic phantom and organ doses were evaluated from the measurement values. Doses for tissues or organs within the scan range were 28-36 mGy in an infant head CT, 3-11 mGy in a chest CT, 5-11 mGy in an abdominal-pelvic CT and 2-14 mGy in a cardiac CT. The doses varied by the differences in the types of CT scanners and scan parameters used at each medical facility. Compared with those for children of various ages, the doses in an infant CT protocol were found to be similar to or slightly smaller than those in a paediatric CT for 5- or 6-y-old children.
A shorter and more specific oral sensitization-based experimental model of food allergy in mice.
Bailón, Elvira; Cueto-Sola, Margarita; Utrilla, Pilar; Rodríguez-Ruiz, Judith; Garrido-Mesa, Natividad; Zarzuelo, Antonio; Xaus, Jordi; Gálvez, Julio; Comalada, Mònica
2012-07-31
Cow's milk protein allergy (CMPA) is one of the most prevalent human food-borne allergies, particularly in children. Experimental animal models have become critical tools with which to perform research on new therapeutic approaches and on the molecular mechanisms involved. However, oral food allergen sensitization in mice requires several weeks and is usually associated with unspecific immune responses. To overcome these inconveniences, we have developed a new food allergy model that takes only two weeks while retaining the main characters of allergic response to food antigens. The new model is characterized by oral sensitization of weaned Balb/c mice with 5 doses of purified cow's milk protein (CMP) plus cholera toxin (CT) for only two weeks and posterior challenge with an intraperitoneal administration of the allergen at the end of the sensitization period. In parallel, we studied a conventional protocol that lasts for seven weeks, and also the non-specific effects exerted by CT in both protocols. The shorter protocol achieves a similar clinical score as the original food allergy model without macroscopically affecting gut morphology or physiology. Moreover, the shorter protocol caused an increased IL-4 production and a more selective antigen-specific IgG1 response. Finally, the extended CT administration during the sensitization period of the conventional protocol is responsible for the exacerbated immune response observed in that model. Therefore, the new model presented here allows a reduction not only in experimental time but also in the number of animals required per experiment while maintaining the features of conventional allergy models. We propose that the new protocol reported will contribute to advancing allergy research. Copyright © 2012 Elsevier B.V. All rights reserved.
Pireau, Nathalie; Cordemans, Virginie; Banse, Xavier; Irda, Nadia; Lichtherte, Sébastien; Kaminski, Ludovic
2017-11-01
Spine surgery still remains a challenge for every spine surgeon, aware of the potential serious outcomes of misplaced instrumentation. Though many studies have highlighted that using intraoperative cone beam CT imaging and navigation systems provides higher accuracy than conventional freehand methods for placement of pedicle screws in spine surgery, few studies are concerned about how to reduce radiation exposure for patients with the use of such technology. One of the main focuses of this study is based on the ALARA principle (as low as reasonably achievable). A prospective randomized trial was conducted in the hybrid operating room between December 2015 and December 2016, including 50 patients operated on for posterior instrumented thoracic and/or lumbar spinal fusion. Patients were randomized to intraoperative 3D acquisition high-dose (standard dose) or low-dose protocol, and a total of 216 pedicle screws were analyzed in terms of screw position. Two different methods were used to measure ionizing radiation: the total skin dose (derived from the dose-area product) and the radiation dose evaluated by thermoluminescent dosimeters on the surgical field. According to Gertzbein and Heary classifications, low-dose protocol provided a significant higher accuracy of pedicle screw placement than the high-dose protocol (96.1 versus 92%, respectively). Seven screws (3.2%), all implanted with the high-dose protocol, needed to be revised intraoperatively. The use of low-dose acquisition protocols reduced patient exposure by a factor of five. This study emphasizes the paramount importance of using low-dose protocols for intraoperative cone beam CT imaging coupled with the navigation system, as it at least does not affect the accuracy of pedicle screw placement and irradiates drastically less.
Sommer, Wieland H; Albrecht, Edda; Bamberg, Fabian; Schenzle, Jan C; Johnson, Thorsten R; Neumaier, Klement; Reiser, Maximilian F; Nikolaou, Konstatin
2010-12-01
The objective of this study was to compare image quality and radiation dose between high-pitch and established retrospectively and prospectively gated cardiac CT protocols using an Alderson-Rando phantom and a set of patients. An anthropomorphic Alderson-Rando phantom equipped with thermoluminiscent detectors and a set of clinical patients underwent the following cardiac CT protocols: high-pitch acquisition (pitch 3.4), prospectively triggered acquisition, and retrospectively gated acquisition (pitch 0.2). For patients with sinus rhythm below 65 beats per minute (bpm), high-pitch protocol was used, whereas for patients in sinus rhythm between 65 and 100 bpm, prospective triggering was used. Patients with irregular heart rates or heart rates of ≥ 100 bpm, were examined using retrospectively gated acquisition. Evaluability of coronary artery segments was determined, and effective radiation dose was derived from the phantom study. In the phantom study, the effective radiation dose as determined with thermoluminescent detector (TLD) measurements was lowest in the high-pitch acquisition (1.21, 3.12, and 11.81 mSv, for the high-pitch, the prospectively triggered, and the retrospectively gated acquisition, respectively). There was a significant difference with respect to the percentage of motion-free coronary artery segments (99%, 87%, and 92% for high-pitch, prospectively triggered, and retrospectively gated, respectively (p < 0.001), whereas image noise was lowest for the high-pitch protocol (p < 0.05). High-pitch scans have the potential to reduce radiation dose up to 61.2% and 89.8% compared with prospectively triggered and retrospectively gated scans. High-pitch protocols lead to excellent image quality when used in patients with stable heart rates below 65 bpm.
Advanced technology development for remote triage applications in bleeding combat casualties.
Ryan, Kathy L; Rickards, Caroline A; Hinojosa-Laborde, Carmen; Gerhardt, Robert T; Cain, Jeffrey; Convertino, Victor A
2011-01-01
Combat developers within the Army have envisioned development of a "wear-and-forget" physiological status monitor (PSM) that will enhance far forward capabilities for assessment of Warrior readiness for battle, as well as for remote triage, diagnosis and decision-making once Soldiers are injured. This paper will review recent work testing remote triage system prototypes in both the laboratory and during field exercises. Current PSM prototypes measure the electrocardiogram and respiration, but we have shown that information derived from these measurements alone will not be suited for specific, accurate triage of combat injuries. Because of this, we have suggested that development of a capability to provide a metric of circulating blood volume status is required for remote triage. Recently, volume status has been successfully modeled using low-level physiological signals obtained from wearable devices as input to machine-learning algorithms; these algorithms are already able to discriminate between a state of physical activity (common in combat) and that of central hypovolemia, and thus show promise for use in wearable remote triage devices.
Schreiner, Markus M; Platzgummer, Hannes; Unterhumer, Sylvia; Weber, Michael; Mistelbauer, Gabriel; Loewe, Christian; Schernthaner, Ruediger E
2017-08-01
To investigate radiation exposure, objective image quality, and the diagnostic accuracy of a BMI-adjusted ultra-low-dose CT angiography (CTA) protocol for the assessment of peripheral arterial disease (PAD), with digital subtraction angiography (DSA) as the standard of reference. In this prospective, IRB-approved study, 40 PAD patients (30 male, mean age 72 years) underwent CTA on a dual-source CT scanner at 80kV tube voltage. The reference amplitude for tube current modulation was personalized based on the body mass index (BMI) with 120 mAs for [BMI≤25] or 150 mAs for [25
Ostensson, Ellinor; Fröberg, Maria; Hjerpe, Anders; Zethraeus, Niklas; Andersson, Sonia
2010-10-01
To assess the cost-effectiveness of using human papillomavirus testing (HPV triage) in the management of women with minor cytological abnormalities in Sweden. An economic analysis based on a clinical trial, complemented with data from published meta-analyses on accuracy of HPV triage. The study takes perspective of the Swedish healthcare system. The Swedish population-based cervical cancer screening program. A decision analytic model was constructed to evaluate cost-effectiveness of HPV triage compared to repeat cytology and immediate colposcopy with biopsy, stratifying by index cytology (ASCUS = atypical squamous cells of undetermined significance, and LSIL = low-grade squamous intraepithelial lesion) and age (23-60 years, <30 years and ≥30 years). Costs, incremental cost, incremental effectiveness and incremental cost per additional high-grade lesion (CIN2+) detected. For women with ASCUS ≥30 years, HPV triage is the least costly alternative, whereas immediate colposcopy with biopsy provides the most effective option at an incremental cost-effectiveness ratio (ICER) of SEK 2,056 per additional case of CIN2+ detected. For LSIL (all age groups) and ASCUS (23-60 years and <30 years), HPV triage is dominated by immediate colposcopy and biopsy. Model results were sensitive to HPV test cost changes. With improved HPV testing techniques at lower costs, HPV triage can become a cost-effective alternative for follow-up of minor cytological abnormalities. Today, immediate colposcopy with biopsy is a cost-effective alternative compared to HPV triage and repeat cytology.
Using Video from Mobile Phones to Improve Pediatric Phone Triage in an Underserved Population.
Freeman, Brandi; Mayne, Stephanie; Localio, A Russell; Luberti, Anthony; Zorc, Joseph J; Fiks, Alexander G
2017-02-01
Video-capable mobile phones are widely available, but few studies have evaluated their use in telephone triage for pediatric patients. We assessed the feasibility, acceptability, and utility of videos sent via mobile phones to enhance pediatric telephone triage for an underserved population with asthma. We recruited children who presented to an urban pediatric emergency department with an asthma exacerbation along with their parent/guardian. Parents and the research team each obtained a video of the child's respiratory exam, and the research team conducted a concurrent in-person rating of respiratory status. We measured the acceptability of families sending videos as part of telephone triage (survey) and the feasibility of this approach (rates of successful video transmission by parents to the research team). To estimate the utility of the video in appropriately triaging children, four clinicians reviewed each video and rated whether they found the video reassuring, neutral, or raising concerns. Among 60 families (78% Medicaid, 85% Black), 80% of parents reported that sending a video would be helpful and 68% reported that a nurse's review of a video would increase their trust in the triage assessment. Most families (75%) successfully transmitted a video to the research team. All clinician raters found the video reassuring regarding the severity of the child's asthma exacerbation for 68% of children. Obtaining mobile phone videos for telephone triage is acceptable to families, feasible, and may help improve the quality of telephone triage in an urban, minority population.
Effectiveness of a myocardial infarction protocol in reducing door-to-ballon time.
Correia, Luis Cláudio Lemos; Brito, Mariana; Kalil, Felipe; Sabino, Michael; Garcia, Guilherme; Ferreira, Felipe; Matos, Iracy; Jacobs, Peter; Ronzoni, Liliana; Noya-Rabelo, Márcia
2013-07-01
An adequate door-to-balloon time (<120 minutes) is the necessary condition for the efficacy of primary angioplasty in infarction to translate into effectiveness. To describe the effectiveness of a quality of care protocol in reducing the door-to-balloon time. Between May 2010 and August 2012, all individuals undergoing primary angioplasty in our hospital were analyzed. The door time was electronically recorded at the moment the patient took a number to be evaluated in the emergency room, which occurred prior to filling the check-in forms and to the triage. The balloon time was defined as the beginning of artery opening (introduction of the first device). The first 5 months of monitoring corresponded to the period of pre-implementation of the protocol. The protocol comprised the definition of a flowchart of actions from patient arrival at the hospital, the team's awareness raising in relation to the prioritization of time, and provision of a periodic feedback on the results and possible inadequacies. A total of 50 individuals were assessed. They were divided into five groups of 10 sequential patients (one group pre- and four groups post-protocol). The door-to-balloon time regarding the 10 cases recorded before protocol implementation was 200 ± 77 minutes. After protocol implementation, there was a progressive reduction of the door-to-balloon time to 142±78 minutes in the first 10 patients, then to 150±50 minutes, 131±37 minutes and, finally, 116±29 minutes in the three sequential groups of 10 patients, respectively. Linear regression between sequential patients and the door-to-balloon time (r = - 0.41) showed a regression coefficient of - 1.74 minutes. The protocol implementation proved effective in the reduction of the door-to-balloon time.
Enjilela, Esmaeil; Lee, Ting-Yim; Hsieh, Jiang; Wisenberg, Gerald; Teefy, Patrick; Yadegari, Andrew; Bagur, Rodrigo; Islam, Ali; Branch, Kelley; So, Aaron
2018-03-01
We implemented and validated a compressed sensing (CS) based algorithm for reconstructing dynamic contrast-enhanced (DCE) CT images of the heart from sparsely sampled X-ray projections. DCE CT imaging of the heart was performed on five normal and ischemic pigs after contrast injection. DCE images were reconstructed with filtered backprojection (FBP) and CS from all projections (984-view) and 1/3 of all projections (328-view), and with CS from 1/4 of all projections (246-view). Myocardial perfusion (MP) measurements with each protocol were compared to those with the reference 984-view FBP protocol. Both the 984-view CS and 328-view CS protocols were in good agreements with the reference protocol. The Pearson correlation coefficients of 984-view CS and 328-view CS determined from linear regression analyses were 0.98 and 0.99 respectively. The corresponding mean biases of MP measurement determined from Bland-Altman analyses were 2.7 and 1.2ml/min/100g. When only 328 projections were used for image reconstruction, CS was more accurate than FBP for MP measurement with respect to 984-view FBP. However, CS failed to generate MP maps comparable to those with 984-view FBP when only 246 projections were used for image reconstruction. DCE heart images reconstructed from one-third of a full projection set with CS were minimally affected by aliasing artifacts, leading to accurate MP measurements with the effective dose reduced to just 33% of conventional full-view FBP method. The proposed CS sparse-view image reconstruction method could facilitate the implementation of sparse-view dynamic acquisition for ultra-low dose CT MP imaging. Copyright © 2017 Elsevier B.V. All rights reserved.
Ali Khawaja, Ranish Deedar; Singh, Sarabjeet; Padole, Atul; Otrakji, Alexi; Lira, Diego; Zhang, Da; Liu, Bob; Primak, Andrew; Xu, George; Kalra, Mannudeep K
2017-08-01
To determine the effect of patient off-centering on point organ radiation dose measurements in a human cadaver scanned with routine abdominal CT protocol. A human cadaver (88 years, body-mass-index 20 kg/m2) was scanned with routine abdominal CT protocol on 128-slice dual source MDCT (Definition Flash, Siemens). A total of 18 scans were performed using two scan protocols (a) 120 kV-200 mAs fixed-mA (CTDIvol 14 mGy) (b) 120 kV-125 ref mAs (7 mGy) with automatic exposure control (AEC, CareDose 4D) at three different positions (a) gantry isocenter, (b) upward off-centering and (c) downward off-centering. Scanning was repeated three times at each position. Six thimble (in liver, stomach, kidney, pancreas, colon and urinary bladder) and four MOSFET dosimeters (on cornea, thyroid, testicle and breast) were placed for calculation of measured point organ doses. Organ dose estimations were retrieved from dose-tracking software (eXposure, Radimetrics). Statistical analysis was performed using analysis of variance. There was a significant difference between the trends of point organ doses with AEC and fixed-mA at all three positions (p < 0.01). Variation in point doses between fixed-mA and AEC protocols were statistically significant across all organs at all Table positions (p < 0.001). There was up to 5-6% decrease in point doses with upward off-centering and in downward off-centering. There were statistical significant differences in point doses from dosimeters and dose-tracking software (mean difference for internal organs, 5-36% for fixed-mA & 7-48% for AEC protocols; p < 0.001; mean difference for surface organs, >92% for both protocols; p < 0.0001). For both protocols, the highest mean difference in point doses was found for stomach and lowest for colon. Measured absorbed point doses in abdominal CT vary with patient-centering in the gantry isocenter. Due to lack of consideration of patient positioning in the dose estimation on automatic software-over estimation of the doses up to 92% was reported. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Dozois, Adeline; Hampton, Lorrie; Kingston, Carlene W; Lambert, Gwen; Porcelli, Thomas J; Sorenson, Denise; Templin, Megan; VonCannon, Shellie; Asimos, Andrew W
2017-12-01
The recently proposed American Heart Association/American Stroke Association EMS triage algorithm endorses routing patients with suspected large vessel occlusion (LVO) acute ischemic strokes directly to endovascular centers based on a stroke severity score. The predictive value of this algorithm for identifying LVO is dependent on the overall prevalence of LVO acute ischemic stroke in the EMS population screened for stroke, which has not been reported. We performed a cross-sectional study of patients transported by our county's EMS agency who were dispatched as a possible stroke or had a primary impression of stroke by paramedics. We determined the prevalence of LVO by reviewing medical record imaging reports based on a priori specified criteria. We enrolled 2402 patients, of whom 777 (32.3%) had an acute stroke-related diagnosis. Among 485 patients with acute ischemic stroke, 24.1% (n=117) had an LVO, which represented only 4.87% (95% confidence interval, 4.05%-5.81%) of the total EMS population screened for stroke. Overall, the prevalence of LVO acute ischemic stroke in our EMS population screened for stroke was low. This is an important consideration for any EMS stroke severity-based triage protocol and should be considered in predicting the rates of overtriage to endovascular stroke centers. © 2017 American Heart Association, Inc.
Ridderikhof, Milan L; Leenders, Noukje; Goddijn, Helma; Schep, Niels W; Lirk, Philipp; Goslings, J Carel; Hollmann, Markus W
2016-09-01
Topical application of lidocaine in wounds has been studied in combination with vasoconstrictive additives, but the effect without these additives is unknown. The objective was to examine use of lidocaine-soaked gauzes without vasoconstrictive agents, in traumatic wounds in adult patients, applied in triage. A prospective pilot study was performed during 6 weeks in the Emergency Department of a level 1 trauma center. Wounds of consecutive adult patients were treated with a nursing protocol, consisting of lidocaine hydrochloride administration directly into the wound and leaving a lidocaine-soaked gauze, until wound treatment. Primary outcome was need for infiltration anesthesia. Secondary outcomes were Numerical Rating Scale (NRS) pain scores, adverse events and patient and physician satisfaction. Forty patients with a traumatic wound were included, 85% male with a wound on the arm. Thirty-seven patients needed a painful procedure as wound treatment. When suturing was necessary, 77% required additional infiltration anesthesia. Mean NRS pain scores decreased from 3.3 to 2.2 after application of the lidocaine gauze. No adverse events were recorded. Of the patients, 60% were satisfied with use of the lidocaine gauzes, compared to 40% of physicians. Lidocaine hydrochloride (2%) gauzes without vasoconstrictive additives cannot replace infiltration anesthesia in traumatic wounds. Copyright © 2016 Elsevier Ltd. All rights reserved.
The Importance of Quality in Ventilation-Perfusion Imaging.
Mann, April; DiDea, Mario; Fournier, France; Tempesta, Daniel; Williams, Jessica; LaFrance, Norman
2018-06-01
As the health care environment continues to change and morph into a system focusing on increased quality and evidence-based outcomes, nuclear medicine technologists must be reminded that they play a critical role in achieving high-quality, interpretable images used to drive patient care, treatment, and best possible outcomes. A survey performed by the Quality Committee of the Society of Nuclear Medicine and Molecular Imaging Technologist Section demonstrated that a clear knowledge gap exists among technologists regarding their understanding of quality, how it is measured, and how it should be achieved by all practicing technologists regardless of role and education level. Understanding of these areas within health care, in conjunction with the growing emphasis on evidence-based outcomes, quality measures, and patient satisfaction, will ultimately elevate the role of nuclear medicine technologists today and into the future. The nuclear medicine role now requires technologists to demonstrate patient assessment skills, practice safety procedures with regard to staff and patients, provide patient education and instruction, and provide physicians with information to assist with the interpretation and outcome of the study. In addition, the technologist must be able to evaluate images by performing technical analysis, knowing the demonstrated anatomy and pathophysiology, and assessing overall quality. Technologists must also be able to triage and understand the disease processes being evaluated and how nuclear medicine diagnostic studies may drive care and treatment. Therefore, it is imperative that nuclear medicine technologists understand their role in the achievement of a high-quality, interpretable study by applying quality principles and understanding and using imaging techniques beyond just basic protocols for every type of disease or system being imaged. This article focuses on quality considerations related to ventilation-perfusion imaging. It provides insight on appropriate imaging techniques and protocols, true imaging variants and tracer distributions versus artifacts that may result in a lower-quality or misinterpreted study, and the use of SPECT and SPECT/CT as an alternative providing a high-quality, interpretable study with better diagnostic accuracy and fewer nondiagnostic procedures than historical planar imaging. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.
No Child Overlooked: Mental Health Triage in the Schools
ERIC Educational Resources Information Center
Wilson, F. Robert; Tang, Mei; Schiller, Kelly; Sebera, Kerry
2009-01-01
Mental health problems among children in schools are on the increase. To exercise due diligence in their responsibility to monitor and promote mental health among our nation's children, school counselors may learn from triage systems employed in hospitals, clinics, and mental health centers. The School Counselor's Triage Model provides school…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boellaard, Ronald, E-mail: r.boellaard@vumc.nl; European Association of Nuclear Medicine Research Ltd., Vienna 1060; European Association of Nuclear Medicine Physics Committee, Vienna 1060
2015-10-15
Purpose: Integrated positron emission tomography/magnetic resonance (PET/MR) systems derive the PET attenuation correction (AC) from dedicated MR sequences. While MR-AC performs reasonably well in clinical patient imaging, it may fail for phantom-based quality control (QC). The authors assess the applicability of different protocols for PET QC in multicenter PET/MR imaging. Methods: The National Electrical Manufacturers Association NU 2 2007 image quality phantom was imaged on three combined PET/MR systems: a Philips Ingenuity TF PET/MR, a Siemens Biograph mMR, and a GE SIGNA PET/MR (prototype) system. The phantom was filled according to the EANM FDG-PET/CT guideline 1.0 and scanned for 5more » min over 1 bed. Two MR-AC imaging protocols were tested: standard clinical procedures and a dedicated protocol for phantom tests. Depending on the system, the dedicated phantom protocol employs a two-class (water and air) segmentation of the MR data or a CT-based template. Differences in attenuation- and SUV recovery coefficients (RC) are reported. PET/CT-based simulations were performed to simulate the various artifacts seen in the AC maps (μ-map) and their impact on the accuracy of phantom-based QC. Results: Clinical MR-AC protocols caused substantial errors and artifacts in the AC maps, resulting in underestimations of the reconstructed PET activity of up to 27%, depending on the PET/MR system. Using dedicated phantom MR-AC protocols, PET bias was reduced to −8%. Mean and max SUV RC met EARL multicenter PET performance specifications for most contrast objects, but only when using the dedicated phantom protocol. Simulations confirmed the bias in experimental data to be caused by incorrect AC maps resulting from the use of clinical MR-AC protocols. Conclusions: Phantom-based quality control of PET/MR systems in a multicenter, multivendor setting may be performed with sufficient accuracy, but only when dedicated phantom acquisition and processing protocols are used for attenuation correction.« less
Hur, Saebeom; Kim, Soo Jin; Park, Ji Hoon; Han, Joon Koo; Choi, Byung Ihn
2012-01-01
Objective To investigate whether the low-tube-voltage (80-kVp), intermediate-tube-current (340-mAs) MDCT using the Iterative Reconstruction in Image Space (IRIS) algorithm improves lesion-to-liver contrast at reduced radiation dosage while maintaining acceptable image noise in the detection of hepatocellular carcinomas (HCC) in thin (mean body mass index, 24 ± 0.4 kg/m2) adults. Subjects and Methods A phantom simulating the liver with HCC was scanned at 50-400 mAs for 80, 100, 120 and 140-kVp. In addition, fifty patients with HCC who underwent multiphasic liver CT using dual-energy (80-kVp and 140-kVp) arterial scans were enrolled. Virtual 120-kVP scans (protocol A) and 80-kVp scans (protocol B) of the late arterial phase were reconstructed with filtered back-projection (FBP), while corresponding 80-kVp scans were reconstructed with IRIS (protocol C). Contrast-to-noise ratio (CNR) of HCCs and abdominal organs were assessed quantitatively, whereas lesion conspicuity, image noise, and overall image quality were assessed qualitatively. Results IRIS effectively reduced image noise, and yielded 29% higher CNR than the FBP at equivalent tube voltage and current in the phantom study. In the quantitative patient study, protocol C helped improve CNR by 51% and 172% than protocols A and B (p < 0.001), respectively, at equivalent radiation dosage. In the qualitative study, protocol C acquired the highest score for lesion conspicuity albeit with an inferior score to protocol A for overall image quality (p < 0.001). Mean effective dose was 2.63-mSv with protocol A and 1.12-mSv with protocols B and C. Conclusion CT using the low-tube-voltage, intermediate-tube-current and IRIS help improve lesion-to-liver CNR of HCC in thin adults during the arterial phase at a lower radiation dose when compared with the standard technique using 120-kVp and FBP. PMID:22438682
Vassallo, James; Beavis, John; Smith, Jason E; Wallis, Lee A
2017-05-01
Triage is a key principle in the effective management at a major incident. There are at least three different triage systems in use worldwide and previous attempts to validate them, have revealed limited sensitivity. Within a civilian adult population, there has been no work to develop an improved system. A retrospective database review of the UK Joint Theatre Trauma Registry was performed for all adult patients (>18years) presenting to a deployed Military Treatment Facility between 2006 and 2013. Patients were defined as Priority One if they had received one or more life-saving interventions from a previously defined list. Using first recorded hospital physiological data (HR/RR/GCS), binary logistic regression models were used to derive optimum physiological ranges to predict need for life-saving intervention. This allowed for the derivation of the Modified Physiological Triage Tool-MPTT (GCS≥14, HR≥100, 12
Pauli, José R.; Cintra, Dennys E.; de Souza, Claudio T.; Ropelle, Eduardo R.; R. da Silva, Adelino S.
2015-01-01
The purpose of this study was to verify the effects of overtraining (OT) on insulin, inflammatory and gluconeogenesis signaling pathways in the livers of mice. Rodents were divided into control (CT), overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up) and overtrained by running without inclination (OTR). Rotarod, incremental load, exhaustive and grip force tests were used to evaluate performance. Thirty-six hours after a grip force test, the livers were extracted for subsequent protein analyses. The phosphorylation of insulin receptor beta (pIRbeta), glycogen synthase kinase 3 beta (pGSK3beta) and forkhead box O1 (pFoxo1) increased in OTR/down versus CT. pGSK3beta was higher in OTR/up versus CT, and pFoxo1 was higher in OTR/up and OTR versus CT. Phosphorylation of protein kinase B (pAkt) and insulin receptor substrate 1 (pIRS–1) were higher in OTR/up versus CT and OTR/down. The phosphorylation of IκB kinase alpha and beta (pIKKalpha/beta) was higher in all OT protocols versus CT, and the phosphorylation of stress-activated protein kinases/Jun amino-terminal kinases (pSAPK-JNK) was higher in OTR/down versus CT. Protein levels of peroxisome proliferator-activated receptor-gamma coactivator 1alpha (PGC-1alpha) and hepatocyte nuclear factor 4alpha (HNF-4alpha) were higher in OTR versus CT. In summary, OTR/down improved the major proteins of insulin signaling pathway but up-regulated TRB3, an Akt inhibitor, and its association with Akt. PMID:26445495
18F-FDG PET/CT in Detecting Metastatic Infection in Children.
Kouijzer, Ilse J E; Blokhuis, Gijsbert J; Draaisma, Jos M T; Oyen, Wim J G; de Geus-Oei, Lioe-Fee; Bleeker-Rovers, Chantal P
2016-04-01
Metastatic infection is a severe complication of bacteremia with high morbidity and mortality. The aim of this study was to investigate the diagnostic value of 18F-FDG PET combined with CT (FDG PET/CT) in children suspected of having metastatic infection. The results of FDG PET/CT scans performed in children because of suspected metastatic infection from September 2003 to June 2013 were analyzed retrospectively. The results were compared with the final clinical diagnosis. FDG PET/CT was performed in 13 children with suspected metastatic infection. Of the total number of FDG PET/CT scans, 38% were clinically helpful. Positive predictive value of FDG PET/CT was 71%, and negative predictive value was 100%. FDG PET/CT appears to be a valuable diagnostic technique in children with suspected metastatic infection. Prospective studies of FDG PET/CT as part of a structured diagnostic protocol are needed to assess the exact additional diagnostic value.
Radiology metrics for safe use and regulatory compliance with CT imaging
NASA Astrophysics Data System (ADS)
Paden, Robert; Pavlicek, William
2018-03-01
The MACRA Act creates a Merit-Based Payment System, with monitoring patient exposure from CT providing one possible quality metric for meeting merit requirements. Quality metrics are also required by The Joint Commission, ACR, and CMS as facilities are tasked to perform reviews of CT irradiation events outside of expected ranges, review protocols for appropriateness, and validate parameters for low dose lung cancer screening. In order to efficiently collect and analyze irradiation events and associated DICOM tags, all clinical CT devices were DICOM connected to a parser which extracted dose related information for storage into a database. Dose data from every exam is compared to the appropriate external standard exam type. AAPM recommended CTDIvol values for head and torso, adult and pediatrics, coronary and perfusion exams are used for this study. CT doses outside the expected range were automatically formatted into a report for analysis and review documentation. CT Technologist textual content, the reason for proceeding with an irradiation above the recommended threshold, is captured for inclusion in the follow up reviews by physics staff. The use of a knowledge based approach in labeling individual protocol and device settings is a practical solution resulting in efficiency of analysis and review. Manual methods would require approximately 150 person-hours for our facility, exclusive of travel time and independent of device availability. An efficiency of 89% time savings occurs through use of this informatics tool including a low dose CT comparison review and low dose lung cancer screening requirements set forth by CMS.
Jain, Avani S.; Shelley, Simon; Muthukrishnan, Indirani; Kalal, Shilpa; Amalachandran, Jaykanth; Chandran, Sureshkumar
2016-01-01
Aims and Objectives: To assess the diagnostic utility of contrast-enhanced 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-ceCT) in localization of tumors in patients with clinical diagnosis of tumor-induced osteomalacia (TIO), in correlation with histopathological results. Materials and Methods: Eight patients (five male and three female) aged 24–60 (mean 42) years with a clinical diagnosis of TIO were included in this prospective study. They underwent whole body (head to toe) FDG PET-ceCT following a standard protocol on Philips GEMINI TF PET-CT scanner. The FDG PET-ceCT results were correlated with postoperative histology findings and clinical follow-up. Results: All the patients had an abnormal PET-ceCT study. The sensitivity of PET-ceCT was 87.5%, and positive predictive value was 100%. The tumor was located in the craniofacial region in 6/8 patients and in bone in 2/8 patients. Hemangiopericytoma was the most common reported histology. All patients underwent surgery, following which they demonstrated clinical improvement. However, one patient with atypical findings on histology did not show any clinical improvement, hence, underwent 68Gallium-DOTANOC PET-ceCT scan for relocalization of the site of the tumor. Conclusion: The tumors causing TIO are small in size and usually located in obscure sites in the body. Hence, head to toe protocol should be followed for FDG PET-ceCT scans with the inclusion of upper limbs. Once the tumor is localized, regional magnetic resonance imaging can be performed for better characterization of soft tissue lesion. Imaging with FDG PET-ceCT plays an important role in detecting the site of the tumor and thereby facilitating timely management. PMID:26917888
Jain, Avani S; Shelley, Simon; Muthukrishnan, Indirani; Kalal, Shilpa; Amalachandran, Jaykanth; Chandran, Sureshkumar
2016-01-01
To assess the diagnostic utility of contrast-enhanced (18)F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-ceCT) in localization of tumors in patients with clinical diagnosis of tumor-induced osteomalacia (TIO), in correlation with histopathological results. Eight patients (five male and three female) aged 24-60 (mean 42) years with a clinical diagnosis of TIO were included in this prospective study. They underwent whole body (head to toe) FDG PET-ceCT following a standard protocol on Philips GEMINI TF PET-CT scanner. The FDG PET-ceCT results were correlated with postoperative histology findings and clinical follow-up. All the patients had an abnormal PET-ceCT study. The sensitivity of PET-ceCT was 87.5%, and positive predictive value was 100%. The tumor was located in the craniofacial region in 6/8 patients and in bone in 2/8 patients. Hemangiopericytoma was the most common reported histology. All patients underwent surgery, following which they demonstrated clinical improvement. However, one patient with atypical findings on histology did not show any clinical improvement, hence, underwent (68)Gallium-DOTANOC PET-ceCT scan for relocalization of the site of the tumor. The tumors causing TIO are small in size and usually located in obscure sites in the body. Hence, head to toe protocol should be followed for FDG PET-ceCT scans with the inclusion of upper limbs. Once the tumor is localized, regional magnetic resonance imaging can be performed for better characterization of soft tissue lesion. Imaging with FDG PET-ceCT plays an important role in detecting the site of the tumor and thereby facilitating timely management.
Zanon, Matheus; Pacini, Gabriel Sartori; de Souza, Vinicius Valério Silveiro; Marchiori, Edson; Meirelles, Gustavo Souza Portes; Szarf, Gilberto; Torres, Felipe Soares; Hochhegger, Bruno
2017-12-01
To assess whether an additional chest ultra-low-dose CT scan to the coronary CT angiography protocol can be used for lung cancer screening among patients with suspected coronary artery disease. 175 patients underwent coronary CT angiography for assessment of coronary artery disease, additionally undergoing ultra-low-dose CT screening to early diagnosis of lung cancer in the same scanner (80kVp and 15mAs). Patients presenting pulmonary nodules were followed-up for two years, repeating low-dose CTs in intervals of 3, 6, or 12 months based on nodule size and growth rate in accordance with National Comprehensive Cancer Network guidelines. Ultra-low-dose CT identified 71 patients with solitary pulmonary nodules (41%), with a mean diameter of 5.50±4.00mm. Twenty-eight were >6mm, and in 79% (n=22) of these cases they were false positive findings, further confirmed by follow-up (n=20), resection (n=1), or biopsy (n=1). Lung cancer was detected in six patients due to CT screening (diagnostic yield: 3%). Among these, four cases could not be detected in the cardiac field of view. Most patients were in early stages of the disease. Two patients diagnosed at advanced stages died due to cancer complications. The addition of the ultra-low-dose CT scan represented a radiation dose increment of 1.22±0.53% (effective dose, 0.11±0.03mSv). Lung cancer might be detected using additional ultra-low-dose protocols in coronary CT angiography scans among patients with suspected coronary artery disease. Copyright © 2017 Elsevier B.V. All rights reserved.
Mirro, Amy E.; Brady, Samuel L.; Kaufman, Robert. A.
2016-01-01
Purpose To implement the maximum level of statistical iterative reconstruction that can be used to establish dose-reduced head CT protocols in a primarily pediatric population. Methods Select head examinations (brain, orbits, sinus, maxilla and temporal bones) were investigated. Dose-reduced head protocols using an adaptive statistical iterative reconstruction (ASiR) were compared for image quality with the original filtered back projection (FBP) reconstructed protocols in phantom using the following metrics: image noise frequency (change in perceived appearance of noise texture), image noise magnitude, contrast-to-noise ratio (CNR), and spatial resolution. Dose reduction estimates were based on computed tomography dose index (CTDIvol) values. Patient CTDIvol and image noise magnitude were assessed in 737 pre and post dose reduced examinations. Results Image noise texture was acceptable up to 60% ASiR for Soft reconstruction kernel (at both 100 and 120 kVp), and up to 40% ASiR for Standard reconstruction kernel. Implementation of 40% and 60% ASiR led to an average reduction in CTDIvol of 43% for brain, 41% for orbits, 30% maxilla, 43% for sinus, and 42% for temporal bone protocols for patients between 1 month and 26 years, while maintaining an average noise magnitude difference of 0.1% (range: −3% to 5%), improving CNR of low contrast soft tissue targets, and improving spatial resolution of high contrast bony anatomy, as compared to FBP. Conclusion The methodology in this study demonstrates a methodology for maximizing patient dose reduction and maintaining image quality using statistical iterative reconstruction for a primarily pediatric population undergoing head CT examination. PMID:27056425
Farrohknia, Nasim; Castrén, Maaret; Ehrenberg, Anna; Lind, Lars; Oredsson, Sven; Jonsson, Håkan; Asplund, Kjell; Göransson, Katarina E
2011-06-30
Emergency department (ED) triage is used to identify patients' level of urgency and treat them based on their triage level. The global advancement of triage scales in the past two decades has generated considerable research on the validity and reliability of these scales. This systematic review aims to investigate the scientific evidence for published ED triage scales. The following questions are addressed: 1. Does assessment of individual vital signs or chief complaints affect mortality during the hospital stay or within 30 days after arrival at the ED?2. What is the level of agreement between clinicians' triage decisions compared to each other or to a gold standard for each scale (reliability)? 3. How valid is each triage scale in predicting hospitalization and hospital mortality? A systematic search of the international literature published from 1966 through March 31, 2009 explored the British Nursing Index, Business Source Premier, CINAHL, Cochrane Library, EMBASE, and PubMed. Inclusion was limited to controlled studies of adult patients (≥ 15 years) visiting EDs for somatic reasons. Outcome variables were death in ED or hospital and need for hospitalization (validity). Methodological quality and clinical relevance of each study were rated as high, medium, or low. The results from the studies that met the inclusion criteria and quality standards were synthesized applying the internationally developed GRADE system. Each conclusion was then assessed as having strong, moderately strong, limited, or insufficient scientific evidence. If studies were not available, this was also noted.We found ED triage scales to be supported, at best, by limited and often insufficient evidence.The ability of the individual vital signs included in the different scales to predict outcome is seldom, if at all, studied in the ED setting. The scientific evidence to assess interrater agreement (reliability) was limited for one triage scale and insufficient or lacking for all other scales. Two of the scales yielded limited scientific evidence, and one scale yielded insufficient evidence, on which to assess the risk of early death or hospitalization in patients assigned to the two lowest triage levels on a 5-level scale (validity).
Smits, Marleen; Keizer, Ellen; Ram, Paul; Giesen, Paul
2017-12-02
Telephone triage is a core but vulnerable part of the care process at out-of-hours general practitioner (GP) cooperatives. In the Netherlands, different instruments have been used for assessing the quality of telephone triage. These instruments focussed mainly on communicational aspects, and less on the medical quality of triage decisions. Our aim was to develop and test a minimum set of items to assess the quality of telephone triage. A national survey among all GP cooperatives in the Netherlands was performed to examine the most important aspects of telephone triage. Next, corresponding items from existing instruments were searched on these topics. Subsequently, an expert panel judged these items on importance, completeness and formulation. The concept KERNset consisted of 24 items about the telephone conversation: 13 medical, ten communicational and one regarding both types. It was pilot tested on measurement characteristics, reliability, validity and variation between triagists. In this pilot study, 114 anonymous calls from four GP cooperatives spread across the Netherlands were judged by three out of eight raters, both internal and external raters. Cronbach's alpha was .94 for the medical items and .75 for the communicational items. Inter-rater reliability: complete agreement between the external raters was 45% and reasonable agreement 73% (difference of maximally one point on the five-point scale). Intra-rater reliability: complete agreement within raters was 55% and reasonable agreement 84%. There were hardly any differences between internal and external raters, but there were differences in strictness between individual raters. The construct validity was confirmed by the high correlation between the general impression of the call and the items of the KERNset. Of the differences within items 19% could be explained by differences between triage nurses, which means the KERNset is able to demonstrate differences between triage nurses. The KERNset can be used to assess the quality of telephone triage. The validity is good and differences between calls and between triage nurses can be measured. A more intensive training for raters could improve the reliability.
Hausfater, Pierre; Amin, Devendra; Amin, Adina; Canavaggio, Pauline; Sauvin, Gabrielle; Bernard, Maguy; Conca, Antoinette; Haubitz, Sebastian; Struja, Tristan; Huber, Andreas; Mueller, Beat; Schuetz, Philipp
2016-01-01
Introduction The inflammatory biomarker pro-adrenomedullin (ProADM) provides additional prognostic information for the risk stratification of general medical emergency department (ED) patients. The aim of this analysis was to develop a triage algorithm for improved prognostication and later use in an interventional trial. Methods We used data from the multi-national, prospective, observational TRIAGE trial including consecutive medical ED patients from Switzerland, France and the United States. We investigated triage effects when adding ProADM at two established cut-offs to a five-level ED triage score with respect to adverse clinical outcome. Results Mortality in the 6586 ED patients showed a step-wise, 25-fold increase from 0.6% to 4.5% and 15.4%, respectively, at the two ProADM cut-offs (≤0.75nmol/L, >0.75–1.5nmol/L, >1.5nmol/L, p ANOVA <0.0001). Risk stratification by combining ProADM within cut-off groups and the triage score resulted in the identification of 1662 patients (25.2% of the population) at a very low risk of mortality (0.3%, n = 5) and 425 patients (6.5% of the population) at very high risk of mortality (19.3%, n = 82). Risk estimation by using ProADM and the triage score from a logistic regression model allowed for a more accurate risk estimation in the whole population with a classification of 3255 patients (49.4% of the population) in the low risk group (0.3% mortality, n = 9) and 1673 (25.4% of the population) in the high-risk group (15.1% mortality, n = 252). Conclusions Within this large international multicenter study, a combined triage score based on ProADM and established triage scores allowed a more accurate mortality risk discrimination. The TRIAGE-ProADM score improved identification of both patients at the highest risk of mortality who may benefit from early therapeutic interventions (rule in), and low risk patients where deferred treatment without negatively affecting outcome may be possible (rule out). PMID:28005916
Ohta, Shoichi; Yoda, Ikushi; Takeda, Munekazu; Kuroshima, Satomi; Uchida, Kotaro; Kawai, Kentaro; Yukioka, Tetsuo
2015-02-01
Though many governmental and nongovernmental efforts for disaster prevention have been sought throughout Japan since the Great East Japan Earthquake on March 11, 2011, most of the preparation efforts for disasters have been based more on structural and conventionalized regulations than on scientific and objective grounds. Problem There has been a lack of scientific knowledge for space utilization for triage posts in disaster drill sessions. This report addresses how participants occupy and make use of the space within a triage post in terms of areas of use and occupied time. The trajectories of human movement by using Ubiquitous Stereo Vision (USV) cameras during two emergency drill sessions held in 2012 in a large commercial building have been measured. The USV cameras collect each participant's travel distance and the wait time before, during, and after undergoing triage. The correlation between the wait time and the space utilization of patients at a triage post has been analyzed. In the first session, there were some spaces not entirely used. This was caused largely by a patient who arrived earlier than others and lingered in the middle area, which caused the later arrivals to crowd the entrance area. On the other hand, in the second session, the area was used in a more evenly-distributed manner. This is mainly because the earlier arrivals were guided to the back space of the triage post (ie, the opposite side of the entrance), and the late arrivals were also guided to the front half, which was not occupied by anyone. As a result, the entire space was effectively utilized without crowding the entrance. This study has shown that this system could measure people's arrival times and the speed of their movements at the triage post, as well as where they are placed until they receive triage. Space utilization can be improved by efficiently planning and controlling the positioning of arriving patients. Based on the results, it has been suggested that for triage operation, it is necessary to efficiently plan and control the placement of patients in order to use strategically limited spatial resources.
2011-01-01
Emergency department (ED) triage is used to identify patients' level of urgency and treat them based on their triage level. The global advancement of triage scales in the past two decades has generated considerable research on the validity and reliability of these scales. This systematic review aims to investigate the scientific evidence for published ED triage scales. The following questions are addressed: 1. Does assessment of individual vital signs or chief complaints affect mortality during the hospital stay or within 30 days after arrival at the ED? 2. What is the level of agreement between clinicians' triage decisions compared to each other or to a gold standard for each scale (reliability)? 3. How valid is each triage scale in predicting hospitalization and hospital mortality? A systematic search of the international literature published from 1966 through March 31, 2009 explored the British Nursing Index, Business Source Premier, CINAHL, Cochrane Library, EMBASE, and PubMed. Inclusion was limited to controlled studies of adult patients (≥15 years) visiting EDs for somatic reasons. Outcome variables were death in ED or hospital and need for hospitalization (validity). Methodological quality and clinical relevance of each study were rated as high, medium, or low. The results from the studies that met the inclusion criteria and quality standards were synthesized applying the internationally developed GRADE system. Each conclusion was then assessed as having strong, moderately strong, limited, or insufficient scientific evidence. If studies were not available, this was also noted. We found ED triage scales to be supported, at best, by limited and often insufficient evidence. The ability of the individual vital signs included in the different scales to predict outcome is seldom, if at all, studied in the ED setting. The scientific evidence to assess interrater agreement (reliability) was limited for one triage scale and insufficient or lacking for all other scales. Two of the scales yielded limited scientific evidence, and one scale yielded insufficient evidence, on which to assess the risk of early death or hospitalization in patients assigned to the two lowest triage levels on a 5-level scale (validity). PMID:21718476
Newgard, Craig D; Mann, N Clay; Hsia, Renee Y; Bulger, Eileen M; Ma, O John; Staudenmayer, Kristan; Haukoos, Jason S; Sahni, Ritu; Kuppermann, Nathan
2013-09-01
Reasons for undertriage (transporting seriously injured patients to nontrauma centers) and the apparent lack of benefit of trauma centers among older adults remain unclear; understanding emergency medical services (EMS) provider reasons for selecting certain hospitals in trauma systems may provide insight to these issues. In this study, the authors evaluated reasons cited by EMS providers for selecting specific hospital destinations for injured patients, stratified by age, injury severity, field triage status, and prognosis. This was a retrospective cohort study of injured children and adults transported by 61 EMS agencies to 93 hospitals (trauma and nontrauma centers) in five regions of the western United States from 2006 through 2008. Hospital records were probabilistically linked to EMS records using trauma registries, state discharge data, and emergency department data. The seven standardized reasons cited by EMS providers for selecting hospital destinations included closest facility, ambulance diversion, physician choice, law enforcement choice, patient or family choice, specialty resource center, and other. "Serious injury" was defined as an Injury Severity Score (ISS) ≥ 16, and unadjusted in-hospital mortality was considered as a marker of prognosis. All analyses were stratified by age in 10-year increments, and descriptive statistics were used to characterize the findings. A total of 176,981 injured patients were evaluated and transported by EMS over the 3-year period, of whom 5,752 (3.3%) had ISS ≥ 16 and 2,773 (1.6%) died. Patient or family choice (50.6%), closest facility (20.7%), and specialty resource center (15.2%) were the most common reasons indicated by EMS providers for selecting destination hospitals; these frequencies varied substantially by patient age. The frequency of patient or family choice increased with increasing age, from 36.4% among 21- to 30-year-olds to 75.8% among those older than 90 years. This trend paralleled undertriage rates and persisted when restricted to patients with serious injuries. Older patients with the worst prognoses were preferentially transported to major trauma centers, a finding that was not explained by field triage protocols. Emergency medical services transport patterns among injured patients are not random, even after accounting for field triage protocols. The selection of hospitals appears to be heavily influenced by patient or family choice, which increases with patient age and involves inherent differences in patient prognosis. © 2013 by the Society for Academic Emergency Medicine.
Cheung, Winston; Myburgh, John; McGuinness, Shay; Chalmers, Debra; Parke, Rachael; Blyth, Fiona; Seppelt, Ian; Parr, Michael; Hooker, Claire; Blackwell, Nikki; DeMonte, Shannon; Gandhi, Kalpesh; Kol, Mark; Kerridge, Ian; Nair, Priya; Saunders, Nicholas M; Saxena, Manoj K; Thanakrishnan, Govindasamy; Naganathan, Vasi
2017-09-01
An influenza pandemic has the potential to overwhelm intensive care resources, but the views of the general public on how resources should be allocated in such a scenario were unknown. We aimed to determine Australian and New Zealand public opinion on how intensive care unit beds should be allocated during an influenza pandemic. A postal questionnaire was sent to 4000 randomly selected registered voters; 2000 people each from the Australian Electoral Commission and New Zealand Electoral Commission rolls. The respondents' preferred method to triage ICU patients in an influenza pandemic. Respondents chose from six methods: use a "first in, first served" approach; allow a senior doctor to decide; use pre-determined health department criteria; use random selection; use the patient's ability to pay; use the importance of the patient to decide. Respondents also rated each of the triage methods for fairness. Australian respondents preferred that patients be triaged to the ICU either by a senior doctor (43.2%) or by pre-determined health department criteria (38.7%). New Zealand respondents preferred that triage be performed by a senior doctor (45.9%). Respondents from both countries perceived triage by a senior doctor and by pre-determined health department criteria to be fair, and the other four methods of triage to be unfair. In an influenza pandemic, when ICU resources would be overwhelmed, survey respondents preferred that ICU triage be performed by a senior doctor, but also perceived the use of pre-determined triage criteria to be fair.
Murdoch, Jamie; Barnes, Rebecca; Pooler, Jillian; Lattimer, Valerie; Fletcher, Emily; Campbell, John L
2015-02-01
Telephone triage represents one strategy to manage demand for face-to-face GP appointments in primary care. Although computer decision-support software (CDSS) is increasingly used by nurses to triage patients, little is understood about how interaction is organized in this setting. Specifically any interactional dilemmas this computer-mediated setting invokes; and how these may be consequential for communication with patients. Using conversation analytic methods we undertook a multi-modal analysis of 22 audio-recorded telephone triage nurse-caller interactions from one GP practice in England, including 10 video-recordings of nurses' use of CDSS during triage. We draw on Goffman's theoretical notion of participation frameworks to make sense of these interactions, presenting 'telling cases' of interactional dilemmas nurses faced in meeting patient's needs and accurately documenting the patient's condition within the CDSS. Our findings highlight troubles in the 'interactional workability' of telephone triage exposing difficulties faced in aligning the proximal and wider distal context that structures CDSS-mediated interactions. Patients present with diverse symptoms, understanding of triage consultations, and communication skills which nurses need to negotiate turn-by-turn with CDSS requirements. Nurses therefore need to have sophisticated communication, technological and clinical skills to ensure patients' presenting problems are accurately captured within the CDSS to determine safe triage outcomes. Dilemmas around how nurses manage and record information, and the issues of professional accountability that may ensue, raise questions about the impact of CDSS and its use in supporting nurses to deliver safe and effective patient care. Copyright © 2014 Elsevier Ltd. All rights reserved.
2011-01-01
Background The criteria for deciding who should be admitted first from a waiting list to a forensic secure hospital are not necessarily the same as those for assessing need. Criteria were drafted qualitatively and tested in a prospective 'real life' observational study over a 6-month period. Methods A researcher rated all those presented at the weekly referrals meeting using the DUNDRUM-1 triage security scale and the DUNDRUM-2 triage urgency scale. The key outcome measure was whether or not the individual was admitted. Results Inter-rater reliability and internal consistency for the DUNDRUM-2 were acceptable. The DUNDRUM-1 triage security score and the DUNDRUM-2 triage urgency score correlated r = 0.663. At the time of admission, after a mean of 23.9 (SD35.9) days on the waiting list, those admitted had higher scores on the DUNDRUM-2 triage urgency scale than those not admitted, with no significant difference between locations (remand or sentenced prisoners, less secure hospitals) at the time of admission. Those admitted also had higher DUNDRUM-1 triage security scores. At baseline the receiver operating characteristic area under the curve for a combined score was the best predictor of admission while at the time of admission the DUNDRUM-2 triage urgency score had the largest AUC (0.912, 95% CI 0.838 to 0.986). Conclusions The triage urgency items and scale add predictive power to the decision to admit. This is particularly true in maintaining equitability between those referred from different locations. PMID:21722397
Challenges for Early Responders to a Nuclear / Radiological Terrorism Incident
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wells, M.A.; Stearns, L.J.; Davie, A.D.
2007-07-01
Even in the best of circumstances, most municipalities would face severe challenges in providing effective incident response to a large scale radiation release caused by nuclear terrorism or accident. Compounding obvious complexities, the effectiveness of first and early responders to a radiological emergency may also be hampered by an insufficient distribution of radiation detection and monitoring equipment, local policies concerning triage and field decontamination of critical victims, malfunctioning communications, inadequate inter-agency agility, and the psychological 'fear' impact on early responders. This paper examines several issues impeding the early response to nuclear terrorism incidents with specific consideration given to the on-goingmore » and forward-thinking preparedness efforts currently being developed in the Sacramento, California region. Specific recommendations are provided addressing hot zone protocols, radiation detection and monitoring equipment, hasty patient packaging techniques, vertically and horizontally integrated pre-event training, mitigating psychological fear, and protocols for the effective 'hand-off' from first responders to subsequent early response-recovery teams. (authors)« less
Research on radiation exposure from CT part of hybrid camera and diagnostic CT
NASA Astrophysics Data System (ADS)
Solný, Pavel; Zimák, Jaroslav
2014-11-01
Research on radiation exposure from CT part of hybrid camera in seven different Departments of Nuclear Medicine (DNM) was conducted. Processed data and effective dose (E) estimations led to the idea of phantom verification and comparison of absorbed doses and software estimation. Anonymous data from about 100 examinations from each DNM was gathered. Acquired data was processed and utilized by dose estimation programs (ExPACT, ImPACT, ImpactDose) with respect to the type of examination and examination procedures. Individual effective doses were calculated using enlisted programs. Preserving the same procedure in dose estimation process allows us to compare the resulting E. Some differences and disproportions during dose estimation led to the idea of estimated E verification. Consequently, two different sets of about 100 of TLD 100H detectors were calibrated for measurement inside the Aldersnon RANDO Anthropomorphic Phantom. Standard examination protocols were examined using a 2 Slice CT- part of hybrid SPECT/CT. Moreover, phantom exposure from body examining protocol for 32 Slice and 64 Slice diagnostic CT scanner was also verified. Absorbed dose (DT,R) measured using TLD detectors was compared with software estimation of equivalent dose HT values, computed by E estimation software. Though, only limited number of cavities for detectors enabled measurement within the regions of lung, liver, thyroid and spleen-pancreas region, some basic comparison is possible.
Shen, Yaqi; Hu, Xuemei; Zou, Xianlun; Zhu, Di; Li, Zhen; Hu, Daoyu
2016-09-01
Imaging communities have already reached a consensus that the radiation dose of computed tomography (CT) should be reduced as much as reasonably achievable to lower population risks. Increasing attention is being paid to iodinated contrast media (CM) induced nephrotoxicity (CIN); a decrease in the intake of iodinated CM is required by increasingly more radiologists. Theoretically, the radiation dose varies with the tube current time and square of the tube voltage, with higher iodine contrast at low photon energies (Huda et al. [2000] Radiology, 21 7, 430-435).The use of low tube voltage is a promising strategy to reduce both the radiation dose and CM burden. The term 'double low' has been coined to describe scanning protocols that reduce radiation dose and iodine intake synchronously. These protocols are becoming increasingly popular in the clinical setting. The aim of this review was to describe all original studies using the 'double low' strategy in the last 5 years. We searched an online electronic database (PubMed) from January 2011 to December 2015 for original studies published on the relationship of low tube voltage with low radiation dose and low iodine contrast media burden in patients undergoing CT scans. Studies that failed to reduce radiation dose or iodine CM burden were excluded in this study. Thirty-seven studies aimed at reducing radiation dose using low tube voltage combined with iodine CM reduced protocols were included in this study. Most studies evaluated conditions associated with arteries. Four were cerebral and neck computed tomography angiography (CTA) studies, 15 were pulmonary CTA (pCTA) and coronary CTA (cCTA) studies, one concerned myocardial perfusion, five studies focused on the thoracic and abdominal aorta, and one investigated renal arteries. Three studies consisted of CT venography (CTV) of the pelvis and lower extremities. Six publications examined the liver, and two focused on the kidney. Overall, this review demonstrates that the low tube voltage CT protocol is a powerful tool to reduce the radiation dose in CTA, especially with pCTA and cCTA. © 2016 John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hinshaw, J. Louis, E-mail: jhinshaw@uwhealth.or; Littrup, Peter J.; Durick, Nathan
2010-12-15
The purpose of this study was to compare a double freeze-thaw protocol to a triple freeze-thaw protocol for pulmonary cryoablation utilizing an in vivo porcine lung model. A total of 18 cryoablations were performed in normal porcine lung utilizing percutaneous technique with 9 each in a double- (10-5-10) and triple-freeze (3-3-7-7-5) protocol. Serial noncontrast CT images were obtained during the ablation. CT imaging findings and pathology were reviewed. No imaging changes were identified during the initial freeze cycle with either protocol. However, during the first thaw cycle, a region of ground glass opacity developed around the probe with both protocols.more » Because the initial freeze was shorter with the triple freeze-thaw protocol, the imaging findings were apparent sooner with this protocol (6 vs. 13 min). Also, despite a shorter total freeze time (15 vs. 20 min), the ablation zone identified with the triple freeze-thaw protocol was not significantly different from the double freeze-thaw protocol (mean diameter: 1.67 {+-} 0.41 cm vs. 1.66 {+-} 0.21 cm, P = 0.77; area: 2.1 {+-} 0.48 cm{sup 2} vs. 1.99 {+-} 0.62 cm{sup 2}, P = 0.7; and circularity: 0.95 {+-} 0.04 vs. 0.96 {+-} 0.03, P = 0.62, respectively). This study suggests that there may be several advantages of a triple freeze-thaw protocol for pulmonary cryoablation, including earlier identification of the imaging findings associated with the ablation, the promise of a shorter procedure time or larger zones of ablation, and theoretically, more effective cytotoxicity related to the additional freeze-thaw cycle.« less
Walk-In Triage Systems in University Counseling Centers
ERIC Educational Resources Information Center
Shaffer, Katharine S.; Love, Michael M.; Chapman, Kelsey M.; Horn, Angela J.; Haak, Patricia P.; Shen, Claire Y. W.
2017-01-01
To meet the complex mental health needs of students, some university counseling centers (UCCs) have implemented walk-in triage intake systems, which have not yet been empirically investigated. This study compared client and clinician differences (N = 5564) between a traditional scheduled intake system (Year 1) and a walk-in triage system (Year 2)…
Calibrating Urgency: Triage Decision-Making in a Pediatric Emergency Department
ERIC Educational Resources Information Center
Patel, Vimla L.; Gutnik, Lily A.; Karlin, Daniel R.; Pusic, Martin
2008-01-01
Triage, the first step in the assessment of emergency department patients, occurs in a highly dynamic environment that functions under constraints of time, physical space, and patient needs that may exceed available resources. Through triage, patients are placed into one of a limited number of categories using a subset of diagnostic information.…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brady, S; Shulkin, B
Purpose: To develop ultra-low dose computed tomography (CT) attenuation correction (CTAC) acquisition protocols for pediatric positron emission tomography CT (PET CT). Methods: A GE Discovery 690 PET CT hybrid scanner was used to investigate the change to quantitative PET and CT measurements when operated at ultra-low doses (10–35 mAs). CT quantitation: noise, low-contrast resolution, and CT numbers for eleven tissue substitutes were analyzed in-phantom. CT quantitation was analyzed to a reduction of 90% CTDIvol (0.39/3.64; mGy) radiation dose from baseline. To minimize noise infiltration, 100% adaptive statistical iterative reconstruction (ASiR) was used for CT reconstruction. PET images were reconstructed withmore » the lower-dose CTAC iterations and analyzed for: maximum body weight standardized uptake value (SUVbw) of various diameter targets (range 8–37 mm), background uniformity, and spatial resolution. Radiation organ dose, as derived from patient exam size specific dose estimate (SSDE), was converted to effective dose using the standard ICRP report 103 method. Effective dose and CTAC noise magnitude were compared for 140 patient examinations (76 post-ASiR implementation) to determine relative patient population dose reduction and noise control. Results: CT numbers were constant to within 10% from the non-dose reduced CTAC image down to 90% dose reduction. No change in SUVbw, background percent uniformity, or spatial resolution for PET images reconstructed with CTAC protocols reconstructed with ASiR and down to 90% dose reduction. Patient population effective dose analysis demonstrated relative CTAC dose reductions between 62%–86% (3.2/8.3−0.9/6.2; mSv). Noise magnitude in dose-reduced patient images increased but was not statistically different from pre dose-reduced patient images. Conclusion: Using ASiR allowed for aggressive reduction in CTAC dose with no change in PET reconstructed images while maintaining sufficient image quality for co-localization of hybrid CT anatomy and PET radioisotope uptake.« less
Eggermont, Florieke; Derikx, Loes C; Free, Jeffrey; van Leeuwen, Ruud; van der Linden, Yvette M; Verdonschot, Nico; Tanck, Esther
2018-03-06
In a multi-center patient study, using different CT scanners, CT-based finite element (FE) models are utilized to calculate failure loads of femora with metastases. Previous studies showed that using different CT scanners can result in different outcomes. This study aims to quantify the effects of (i) different CT scanners; (ii) different CT protocols with variations in slice thickness, field of view (FOV), and reconstruction kernel; and (iii) air between calibration phantom and patient, on Hounsfield Units (HU), bone mineral density (BMD), and FE failure load. Six cadaveric femora were scanned on four CT scanners. Scans were made with multiple CT protocols and with or without an air gap between the body model and calibration phantom. HU and calibrated BMD were determined in cortical and trabecular regions of interest. Non-linear isotropic FE models were constructed to calculate failure load. Mean differences between CT scanners varied up to 7% in cortical HU, 6% in trabecular HU, 6% in cortical BMD, 12% in trabecular BMD, and 17% in failure load. Changes in slice thickness and FOV had little effect (≤4%), while reconstruction kernels had a larger effect on HU (16%), BMD (17%), and failure load (9%). Air between the body model and calibration phantom slightly decreased the HU, BMD, and failure loads (≤8%). In conclusion, this study showed that quantitative analysis of CT images acquired with different CT scanners, and particularly reconstruction kernels, can induce relatively large differences in HU, BMD, and failure loads. Additionally, if possible, air artifacts should be avoided. © 2018 Orthopaedic Research Society. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society. J Orthop Res. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. on behalf of the Orthopaedic Research Society.
Noël, Peter B; Engels, Stephan; Köhler, Thomas; Muenzel, Daniela; Franz, Daniela; Rasper, Michael; Rummeny, Ernst J; Dobritz, Martin; Fingerle, Alexander A
2018-01-01
Background The explosive growth of computer tomography (CT) has led to a growing public health concern about patient and population radiation dose. A recently introduced technique for dose reduction, which can be combined with tube-current modulation, over-beam reduction, and organ-specific dose reduction, is iterative reconstruction (IR). Purpose To evaluate the quality, at different radiation dose levels, of three reconstruction algorithms for diagnostics of patients with proven liver metastases under tumor follow-up. Material and Methods A total of 40 thorax-abdomen-pelvis CT examinations acquired from 20 patients in a tumor follow-up were included. All patients were imaged using the standard-dose and a specific low-dose CT protocol. Reconstructed slices were generated by using three different reconstruction algorithms: a classical filtered back projection (FBP); a first-generation iterative noise-reduction algorithm (iDose4); and a next generation model-based IR algorithm (IMR). Results The overall detection of liver lesions tended to be higher with the IMR algorithm than with FBP or iDose4. The IMR dataset at standard dose yielded the highest overall detectability, while the low-dose FBP dataset showed the lowest detectability. For the low-dose protocols, a significantly improved detectability of the liver lesion can be reported compared to FBP or iDose 4 ( P = 0.01). The radiation dose decreased by an approximate factor of 5 between the standard-dose and the low-dose protocol. Conclusion The latest generation of IR algorithms significantly improved the diagnostic image quality and provided virtually noise-free images for ultra-low-dose CT imaging.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gingold, E; Dave, J
2014-06-01
Purpose: The purpose of this study was to compare a new model-based iterative reconstruction with existing reconstruction methods (filtered backprojection and basic iterative reconstruction) using quantitative analysis of standard image quality phantom images. Methods: An ACR accreditation phantom (Gammex 464) and a CATPHAN600 phantom were scanned using 3 routine clinical acquisition protocols (adult axial brain, adult abdomen, and pediatric abdomen) on a Philips iCT system. Each scan was acquired using default conditions and 75%, 50% and 25% dose levels. Images were reconstructed using standard filtered backprojection (FBP), conventional iterative reconstruction (iDose4) and a prototype model-based iterative reconstruction (IMR). Phantom measurementsmore » included CT number accuracy, contrast to noise ratio (CNR), modulation transfer function (MTF), low contrast detectability (LCD), and noise power spectrum (NPS). Results: The choice of reconstruction method had no effect on CT number accuracy, or MTF (p<0.01). The CNR of a 6 HU contrast target was improved by 1–67% with iDose4 relative to FBP, while IMR improved CNR by 145–367% across all protocols and dose levels. Within each scan protocol, the CNR improvement from IMR vs FBP showed a general trend of greater improvement at lower dose levels. NPS magnitude was greatest for FBP and lowest for IMR. The NPS of the IMR reconstruction showed a pronounced decrease with increasing spatial frequency, consistent with the unusual noise texture seen in IMR images. Conclusion: Iterative Model Reconstruction reduces noise and improves contrast-to-noise ratio without sacrificing spatial resolution in CT phantom images. This offers the possibility of radiation dose reduction and improved low contrast detectability compared with filtered backprojection or conventional iterative reconstruction.« less
Fellin, Francesco; Righetto, Roberto; Fava, Giovanni; Trevisan, Diego; Amelio, Dante; Farace, Paolo
2017-03-01
To investigate the range errors made in treatment planning due to the presence of the immobilization devices along the proton beam path. The measured water equivalent thickness (WET) of selected devices was measured by a high-energy spot and a multi-layer ionization chamber and compared with that predicted by treatment planning system (TPS). Two treatment couches, two thermoplastic masks (both un-stretched and stretched) and one headrest were selected. At TPS, every immobilization device was modelled as being part of the patient. The following parameters were assessed: CT acquisition protocol, dose-calculation grid-sizes (1.5 and 3.0mm) and beam-entrance with respect to the devices (coplanar and non-coplanar). Finally, the potential errors produced by a wrong manual separation between treatment couch and the CT table (not present during treatment) were investigated. In the thermoplastic mask, there was a clear effect due to beam entrance, a moderate effect due to the CT protocols and almost no effect due to TPS grid-size, with 1mm errors observed only when thick un-stretched portions were crossed by non-coplanar beams. In the treatment couches the WET errors were negligible (<0.3mm) regardless of the grid-size and CT protocol. The potential range errors produced in the manual separation between treatment couch and CT table were small with 1.5mm grid-size, but could be >0.5mm with a 3.0mm grid-size. In the headrest, WET errors were negligible (0.2mm). With only one exception (un-stretched mask, non-coplanar beams), the WET of all the immobilization devices was properly modelled by the TPS. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Lee, Seung Hyun; Kim, Myung-Joon; Yoon, Choon-Sik; Lee, Mi-Jung
2012-09-01
To retrospectively compare radiation dose and image quality of pediatric chest CT using a routine dose protocol reconstructed with filtered back projection (FBP) (the Routine study) and a low-dose protocol with 50% adaptive statistical iterative reconstruction (ASIR) (the ASIR study). We retrospectively reviewed chest CT performed in pediatric patients who underwent both the Routine study and the ASIR study on different days between January 2010 and August 2011. Volume CT dose indices (CTDIvol), dose length products (DLP), and effective doses were obtained to estimate radiation dose. The image quality was evaluated objectively as noise measured in the descending aorta and paraspinal muscle, and subjectively by three radiologists for noise, sharpness, artifacts, and diagnostic acceptability using a four-point scale. The paired Student's t-test and the Wilcoxon signed-rank test were used for statistical analysis. Twenty-six patients (M:F=13:13, mean age 11.7) were enrolled. The ASIR studies showed 60.3%, 56.2%, and 55.2% reductions in CTDIvol (from 18.73 to 7.43 mGy, P<0.001), DLP (from 307.42 to 134.51 mGy×cm, P<0.001), and effective dose (from 4.12 to 1.84 mSv, P<0.001), respectively, compared with the Routine studies. The objective noise was higher in the paraspinal muscle of the ASIR studies (20.81 vs. 16.67, P=0.004), but was not different in the aorta (18.23 vs. 18.72, P=0.726). The subjective image quality demonstrated no difference between the two studies. A low-dose protocol with 50% ASIR allows radiation dose reduction in pediatric chest CT by more than 55% while maintaining image quality. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Dijkstra, Maaike G; van Niekerk, Dirk; Rijkaart, Dorien C; van Kemenade, Folkert J; Heideman, Daniëlle A M; Snijders, Peter J F; Meijer, Chris J L M; Berkhof, Johannes
2014-01-01
High-risk human papillomavirus (hrHPV) testing has higher sensitivity but lower specificity than cytology for cervical (pre)-cancerous lesions. Therefore, triage of hrHPV-positive women is needed in cervical cancer screening. A cohort of 1,100 hrHPV-positive women, from a population-based screening trial (POBASCAM: n = 44,938; 29-61 years), was used to evaluate 10 triage strategies, involving testing at baseline and six months with combinations of cytology, HPV16/18 genotyping, and/or repeat hrHPV testing. Clinical endpoint was cervical intraepithelial neoplasia grade 3 or worse (CIN3(+)) detected within four years; results were adjusted for women not attending repeat testing. A triage strategy was considered acceptable, when the probability of no CIN3(+) after negative triage (negative predictive value, NPV) was at least 98%, and the CIN3(+) risk after positive triage (positive predictive value, PPV) was at least 20%. Triage at baseline with cytology only yielded an NPV of 94.3% [95% confidence interval (CI), 92.0-96.0] and a PPV of 39.7% (95% CI, 34.0-45.6). An increase in NPV, against a modest decrease in PPV, was obtained by triaging women with negative baseline cytology by repeat cytology (NPV 98.5% and PPV 34.0%) or by baseline HPV16/18 genotyping (NPV 98.8% and PPV 28.5%). The inclusion of both HPV16/18 genotyping at baseline and repeat cytology testing provided a high NPV (99.6%) and a moderately high PPV (25.6%). Triaging hrHPV-positive women by cytology at baseline and after 6 to 12 months, possibly in combination with baseline HPV16/18 genotyping, seems acceptable for cervical cancer screening. Implementable triage strategies are provided for primary hrHPV screening in an organized setting.
The emergency department prediction of disposition (EPOD) study.
Vaghasiya, Milan R; Murphy, Margaret; O'Flynn, Daniel; Shetty, Amith
2014-11-01
Emergency departments (ED) continue to evolve models of care and streaming as interventions to tackle the effects of access block and overcrowding. Tertiary ED may be able to design patient-flow based on predicted dispositions in the department. Segregating discharge-stream patients may help develop patient-flows within the department, which is less affected by availability of beds in a hospital. We aim to determine if triage nurses and ED doctors can predict disposition outcomes early in the patient journey and thus lead to successful streaming of patients in the ED. During this study, triage nurses and ED doctors anonymously predicted disposition outcomes for patients presenting to triage after their brief assessments. Patient disposition at the 24-h post ED presentation was considered as the actual outcome and compared against predicted outcomes. Triage nurses were able to predict actual discharges of 445 patients out of 490 patients with a positive predictive value (PPV) of 90.8% (95% CI 87.8-93.2%). ED registrars were able to predict actual discharges of 85 patients out of 93 patients with PPV of 91.4% (95% CI 83.3-95.9%). ED consultants were able to predict actual discharges of 111 patients out of 118 patients with PPV 94.1% (95% CI 87.7-97.4%). PPVs for admission among ED consultants, ED registrars and Triage nurses were 59.7%, 54.4% and 48.5% respectively. Triage nurses, ED consultants and ED registrars are able to predict a patient's discharge disposition at triage with high levels of confidence. Triage nurses, ED consultants, and ED registrars can predict patients who are likely to be admitted with equal ability. This data may be used to develop specific admission and discharge streams based on early decision-making in EDs by triage nurses, ED registrars or ED consultants. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.
Madrzak, Dorota; Mikołajczak, Renata; Kamiński, Grzegorz
2016-01-01
The aim of this study was the assessment of utility of somatostatin receptor scintigraphy (SRS) by SPECT imaging using 99mTc-EDDA/HYNIC-Tyr3-octreotide (99mTc-EDDA/HYNIC-TOC) in patients with neuroendocrine neoplasm (NEN) or suspected NEN, referred to Nuclear Medicine Dept. of Voivodship Specialty Center in Rzeszow. The selected group of patients was referred also to 68Ga PET/CT. The posed question was the ratio of patients for whom PET/CT with 68Ga would change their management. The distribution of somatostatin receptors was imaged using 99mTc-EDDA/HYNIC-TOC in 61 planar and SPECT studies between 13/05/2010 and 04/02/2013 in Nuclear Medicine Dept. of Voivodship Specialty Center in Rzeszow. The patient age was within a range of 17-80, with the average age of 57.6. The average age of women (65% of patients over-all) was 55.6 and the average age of men (35% of patients overall) was 61.4. In 46 participants (75% of the study group), that underwent SRS, NEN was documented using pathology tests. Selected patients were referred to PET/CT with 68Ga labeled somatostatin analogs, DOTATATE or DOTANOC. This study group consisted of 14 female and 10 male participants with age range of 35-77 and average age of 55.5 years. Patients were classified into 3 groups, as follows: detection - referral due to clinical symptoms and/or biochemical markers (CgA-Chromogranin A, IAA-indoleacetic acid) with the aim of primary diagnosis, staging - referral with the aim of assessment of tumor spread, and follow-up - assessment of the therapy. Out of 61 patients, 24 underwent both 99mTc-EDDA/HYNIC-Tyr3-octreotide SPECT and 68Ga PET/CT. The result of PET/CT was used as a basis for further evaluation. Therefore, the patients were divided into groups; true positive TP (confirmed presence of tissue somatostatin receptors with 68Ga PET/CT) and TN (68Ga PET/CT did not detect any changes and the results were comparable and had the same influence on treatment protocol). In case of SPECT, the results were assigned as follows: TP, TN (in cases where the results were confirmed by 68Ga PET/CT), FP (patient's scintigraphy demonstrated focal change by SPECT but not PET/CT) and FN (99mTc-EDDA/HYNIC-Tyr3-octreotide SPECT failed to demonstrate any abnormalities; however, the treatment protocol was changed after PET/CT). The accuracy of SPECT diagnosis was found to be as high as 91.6%. Only in 8.4% of patients the additional PET/CT with 68Ga-labeled somatostatin analog changed the treatment protocol.
Park, Clara; Gruber-Rouh, Tatjana; Leithner, Doris; Zierden, Amelie; Albrecht, Mortiz H; Wichmann, Julian L; Bodelle, Boris; Elsabaie, Mohamed; Scholtz, Jan-Erik; Kaup, Moritz; Vogl, Thomas J; Beeres, Martin
2016-10-10
Evaluation of latest generation automated attenuation-based tube potential selection (ATPS) impact on image quality and radiation dose in contrast-enhanced chest-abdomen-pelvis computed tomography examinations for gynaecologic cancer staging. This IRB approved single-centre, observer-blinded retrospective study with a waiver for informed consent included a total of 100 patients with contrast-enhanced chest-abdomen-pelvis CT for gynaecologic cancer staging. All patients were examined with activated ATPS for adaption of tube voltage to body habitus. 50 patients were scanned on a third-generation dual-source CT (DSCT), and another 50 patients on a second-generation DSCT. Predefined image quality setting remained stable between both groups at 120 kV and a current of 210 Reference mAs. Subjective image quality assessment was performed by two blinded readers independently. Attenuation and image noise were measured in several anatomic structures. Signal-to-noise ratio (SNR) was calculated. For the evaluation of radiation exposure, CT dose index (CTDI vol ) values were compared. Diagnostic image quality was obtained in all patients. The median CTDI vol (6.1 mGy, range 3.9-22 mGy) was 40 % lower when using the algorithm compared with the previous ATCM protocol (median 10.2 mGy · cm, range 5.8-22.8 mGy). A reduction in potential to 90 kV occurred in 19 cases, a reduction to 100 kV in 23 patients and a reduction to 110 kV in 3 patients of our experimental cohort. These patients received significantly lower radiation exposure compared to the former used protocol. Latest generation automated ATPS on third-generation DSCT provides good diagnostic image quality in chest-abdomen-pelvis CT while average radiation dose is reduced by 40 % compared to former ATPS protocol on second-generation DSCT.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Winslow, J; Hurwitz, L; Christianson, O
2014-06-01
Purpose: In CT scanners, the automatic exposure control (AEC) tube current prescription depends on the acquired prescan localizer image(s). The purpose of this study was to quantify the effect that table height, patient size, and localizer acquisition order may have on the reproducibility in prescribed dose. Methods: Three phantoms were used for this study: the Mercury Phantom (comprises three tapered and four uniform regions of polyethylene 16, 23, 30, and 37 cm in diameter), acrylic sheets, and an adult anthropomorphic phantom. Phantoms were positioned per clinical protocol by our chief CT technologist or broader symmetry. Using a GE Discovery CT750HDmore » scanner, a lateral (LAT) and posterior-anterior (PA) localizer was acquired for each phantom at different table heights. AEC scan acquisitions were prescribed for each combination of phantom, localizer orientation, and table height; the displayed volume CTDI was recorded for each. Results were analyzed versus table height. Results: For the two largest Mercury Phantom section scans based on the PA localizer, the percent change in volume CTDI from ideal were at least 20% lower and 35% greater for table heights 4 cm above and 4 cm below proper centering, respectively. For scans based on the LAT localizer, the percent change in volume CTDI from ideal were no greater than 12% different for 4 cm differences in table height. The properly centered PA and LAT localizer-based volume CTDI values were within 13% of each other. Conclusion: Since uncertainty in vertical patient positioning is inherently greater than lateral positioning and because the variability in dose exceeds any dose penalties incurred, the LAT localizer should be used to precisely and reproducibly deliver the intended amount of radiation prescribed by CT protocols. CT protocols can be adjusted to minimize the expected change in average patient dose.« less
Hinds, Nicholas; Borah, Amit; Yoo, Erika J
2017-06-01
To compare outcomes of patients refused medical intensive care unit (MICU) admission overnight to those refused during the day and to examine the impact of the intensivist in triage. Retrospective, observational study of patients refused MICU admission at an urban university hospital. Of 294 patients, 186 (63.3%) were refused admission overnight compared to 108 (36.7%) refused during the day. Severity-of-illness by the Mortality Probability Model was similar between the two groups (P=.20). Daytime triage refusals were more likely to be staffed by an intensivist (P=.01). After risk-adjustment, daytime refusals had a lower odds of subsequent ICU admission (OR 0.46, 95% CI 0.22-0.95, P=.04) than patients triaged at night. There was no evidence for interaction between time of triage and intensivist staffing of the patient (P=.99). Patients refused MICU admission overnight are more likely to be later admitted to an ICU than patients refused during the day. However, the mechanism for this observation does not appear to depend on the intensivist's direct evaluation of the patient. Further investigation into the clinician-specific effects of ICU triage and identification of potentially modifiable hospital triage practices will help to improve both ICU utilization and patient safety. Copyright © 2017 Elsevier Inc. All rights reserved.
State of the art: dual-energy CT of the abdomen.
Marin, Daniele; Boll, Daniel T; Mileto, Achille; Nelson, Rendon C
2014-05-01
Recent technologic advances in computed tomography (CT)--enabling the nearly simultaneous acquisition of clinical images using two different x-ray energy spectra--have sparked renewed interest in dual-energy CT. By interrogating the unique characteristics of different materials at different x-ray energies, dual-energy CT can be used to provide quantitative information about tissue composition, overcoming the limitations of attenuation-based conventional single-energy CT imaging. In the past few years, intensive research efforts have been devoted to exploiting the unique and powerful opportunities of dual-energy CT for a variety of clinical applications. This has led to CT protocol modifications for radiation dose reduction, improved diagnostic performance for detection and characterization of diseases, as well as image quality optimization. In this review, the authors discuss the basic principles, instrumentation and design, examples of current clinical applications in the abdomen and pelvis, and future opportunities of dual-energy CT.
NASA Astrophysics Data System (ADS)
Tsai, Chia-Jung; Lee, Jason J. S.; Chen, Liang-Kuang; Mok, Greta S. P.; Hsu, Shih-Ming; Wu, Tung-Hsin
2011-10-01
Triple rule-out coronary CT angiography (TRO-CTA) is a new approach for providing noninvasive visualization of coronary arteries with simultaneous evaluation of pulmonary arteries, thoracic aorta and other intrathoracic structures. The increasing use of TRO-CTA examination with longer scan length is associated with the concerns about radiation dose and their corresponding cancer risk. The purpose of this study is to evaluate organ dose and effective dose for the TRO-CTA examination with 2 scan lengths: TRO std and TRO ext, using 256-slice CT. TRO-CTA examinations were performed on a 256-slice CT scanner without ECG-based tube current modulation. Absorbed organ doses were measured using an anthropomorphic phantom and thermal-luminance dosimeters (TLDs). Effective dose was determined by taking a sum of the measured absorbed organ doses multiplied with the tissue weighting factor based on ICRP-103, and compared to that calculated using the dose-length product (DLP) method. We obtained high organ doses in the thyroid, esophagus, breast, heart and lung in both TRO-CTA protocols. Effective doses of the TRO std and TRO ext protocols with the phantom method were 26.37 and 42.49 mSv, while those with the DLP method were 19.68 and 38.96 mSv, respectively. Our quantitative dose information establishes a relationship between radiation dose and scanning length, and can provide a practical guidance to best clinical practice.
An Intraoperative Site-specific Bone Density Device: A Pilot Test Case.
Arosio, Paolo; Moschioni, Monica; Banfi, Luca Maria; Di Stefano, Anilo Alessio
2015-08-01
This paper reports a case of all-on-four rehabilitation where bone density at implant sites was assessed both through preoperative computed tomographic (CT) scans and using a micromotor working as an intraoperative bone density measurement device. Implant-supported rehabilitation is a predictable treatment option for tooth replacement whose success depends on the clinician's experience, the implant characteristics and location and patient-related factors. Among the latter, bone density is a determinant for the achievement of primary implant stability and, eventually, for implant success. The ability to measure bone density at the placement site before implant insertion could be important in the clinical setting. A patient complaining of masticatory impairment was presented with a plan calling for extraction of all her compromised teeth, followed by implant rehabilitation. A week before surgery, she underwent CT examination, and the bone density on the CT scans was measured. When the implant osteotomies were created, the bone density was again measured with a micromotor endowed with an instantaneous torque-measuring system. The implant placement protocols were adapted for each implant, according to the intraoperative measurements, and the patient was rehabilitated following an all-on-four immediate loading protocol. The bone density device provided valuable information beyond that obtained from CT scans, allowing for site-specific, intraoperative assessment of bone density immediately before implant placement and an estimation of primary stability just after implant insertion. Measuring jaw-bone density could help clinicians to select implant-placement protocols and loading strategies based on site-specific bone features.
Nemsadze, G; Urushadze, O
2011-11-01
Using of mutislice spiral CT as first line examination for the diagnosis of Acute Facial trauma in the setting of Polytrauma reduces both: valuable time and cost of patient treatment. After a brief clinical examination, MDCT was performed depending on the area of injury, using a slice thickness of 0.65 mm. The obtained data were analyzed using 3D, MIP and Standard axial with Bone reconstruction protocols. 64 polytrauma patients were evaluated with both Anterior and Lateral craniography (plain skull X ray: AP and Lateral) and Multi Slice CT. Craniography detected only 18 cases of traumatic injuries of facial bones, but exact range of dislocation and accurate management plan could not be established. In the same 64 cases, Multislice CT revealed localization of all existed fractures, range of fragment dislocation, soft tissue damage and status of Paranasal sinus in 62 cases (96.8%). In two cases MS CT missed the facial fracture, in one case the examination was complicated because of bone thinness and numerous fracture fragments, in another multiple foreign body artifacts complicated the investigation. The study results show that, CT investigation based on our MDCT polytrauma protocol, detects all more or less serious facial bone injuries.
Heusch, Philipp; Buchbender, Christian; Köhler, Jens; Nensa, Felix; Gauler, Thomas; Gomez, Benedikt; Reis, Henning; Stamatis, Georgios; Kühl, Hilmar; Hartung, Verena; Heusner, Till A
2014-03-01
Therapeutic decisions in non-small cell lung cancer (NSCLC) patients depend on the tumor stage. PET/CT with (18)F-FDG is widely accepted as the diagnostic standard of care. The purpose of this study was to compare a dedicated pulmonary (18)F-FDG PET/MR imaging protocol with (18)F-FDG PET/CT for primary and locoregional lymph node staging in NSCLC patients using histopathology as the reference. Twenty-two patients (12 men, 10 women; mean age ± SD, 65.1 ± 9.1 y) with histopathologically confirmed NSCLC underwent (18)F-FDG PET/CT, followed by (18)F-FDG PET/MR imaging, including a dedicated pulmonary MR imaging protocol. T and N staging according to the seventh edition of the American Joint Committee on Cancer staging manual was performed by 2 readers in separate sessions for (18)F-FDG PET/CT and PET/MR imaging, respectively. Results from histopathology were used as the standard of reference. The mean and maximum standardized uptake value (SUV(mean) and SUV(max), respectively) and maximum diameter of the primary tumor was measured and compared in (18)F-FDG PET/CT and PET/MR imaging. PET/MR imaging and (18)F-FDG PET/CT agreed on T stages in 16 of 16 of patients (100%). All patients were correctly staged by (18)F-FDG PET/CT and PET/MR (100%), compared with histopathology. There was no statistically significant difference between (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging for lymph node metastases detection (P = 0.48). For definition of thoracic N stages, PET/MR imaging and (18)F-FDG PET/CT were concordant in 20 of 22 patients (91%). PET/MR imaging determined the N stage correctly in 20 of 22 patients (91%). (18)F-FDG PET/CT determined the N stage correctly in 18 of 22 patients (82%). The mean differences for SUV(mean) and SUV(max) of NSCLC in (18)F-FDG PET/MR imaging and (18)F-FDG PET/CT were 0.21 and -5.06. These differences were not statistically significant (P > 0.05). The SUV(mean) and SUV(max) measurements derived from (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging exhibited a high correlation (R = 0.74 and 0.86, respectively; P < 0.0001). Size measurements showed an excellent correlation between (18)F-FDG PET/MR imaging and (18)F-FDG PET/CT (R = 0.99; P < 0.0001). The lower and upper limits of agreement between (18)F-FDG PET/CT and (18)F-FDG PET/MR imaging using Bland-Altman analysis were -2.34 to 3.89 for SUV(mean), -7.42 to 4.40 for SUV(max), and -0.59 to 0.83 for the tumor size, respectively. (18)F-FDG PET/MR imaging using a dedicated pulmonary MR imaging protocol, compared with (18)F-FDG PET/CT, does not provide advantages in thoracic staging in NSCLC patients.
Short-term adaptations following Complex Training in team-sports: A meta-analysis
Martinez-Rodriguez, Alejandro; Calleja-González, Julio; Alcaraz, Pedro E.
2017-01-01
Objective The purpose of this meta-analysis was to study the short-term adaptations on sprint and vertical jump (VJ) performance following Complex Training (CT) in team-sports. CT is a resistance training method aimed at developing both strength and power, which has a direct effect on sprint and VJ. It consists on alternating heavy resistance training exercises with plyometric/power ones, set for set, on the same workout. Methods A search of electronic databases up to July 2016 (PubMed-MEDLINE, SPORTDiscus, Web of Knowledge) was conducted. Inclusion criteria: 1) at least one CT intervention group; 2) training protocols ≥4-wks; 3) sample of team-sport players; 4) sprint or VJ as an outcome variable. Effect sizes (ES) of each intervention were calculated and subgroup analyses were performed. Results A total of 9 studies (13 CT groups) met the inclusion criteria. Medium effect sizes (ES) (ES = 0.73) were obtained for pre-post improvements in sprint, and small (ES = 0.41) in VJ, following CT. Experimental-groups presented better post-intervention sprint (ES = 1.01) and VJ (ES = 0.63) performance than control-groups. Sprint large ESs were exhibited in younger athletes (<20 years old; ES = 1.13); longer CT interventions (≥6 weeks; ES = 0.95); conditioning activities with intensities ≤85% 1RM (ES = 0.96) and protocols with frequencies of <3 sessions/week (ES = 0.84). Medium ESs were obtained in Division I players (ES = 0.76); training programs >12 total sessions (ES = 0.74). VJ Large ESs in programs with >12 total sessions (ES = 0.81). Medium ESs obtained for under-Division I individuals (ES = 0.56); protocols with intracomplex rest intervals ≥2 min (ES = 0.55); conditioning activities with intensities ≤85% 1RM (ES = 0.64); basketball/volleyball players (ES = 0.55). Small ESs were found for younger athletes (ES = 0.42); interventions ≥6 weeks (ES = 0.45). Conclusions CT interventions have positive medium effects on sprint performance and small effects on VJ in team-sport athletes. This training method is a suitable option to include in the season planning. PMID:28662108
Portnoy, Orith; Guranda, Larisa; Apter, Sara; Eiss, David; Amitai, Marianne Michal; Konen, Eli
2011-11-01
The purpose of this study was to compare opacification of the urinary collecting system and radiation dose associated with three-phase 64-MDCT urographic protocols and those associated with a split-bolus dual-phase protocol including furosemide. Images from 150 CT urographic examinations performed with three scanning protocols were retrospectively evaluated. Group A consisted of 50 sequentially registered patients who underwent a three-phase protocol with saline infusion. Group B consisted of 50 sequentially registered patients who underwent a reduced-radiation three-phase protocol with saline. Group C consisted of 50 sequentially registered patients who underwent a dual-phase split-bolus protocol that included a low-dose furosemide injection. Opacification of the urinary collecting system was evaluated with segmental binary scoring. Contrast artifacts were evaluated, and radiation doses were recorded. Results were compared by analysis of variance. A significant reduction in mean effective radiation dose was found between groups A and B (p < 0.001) and between groups B and C (p < 0.001), resulting in 65% reduction between groups A and C (p < 0.001). This reduction did not significantly affect opacification score in any of the 12 urinary segments (p = 0.079). In addition, dense contrast artifacts overlying the renal parenchyma observed with the three-phase protocols (groups A and B) were avoided with the dual-phase protocol (group C) (p < 0.001). A dual-phase protocol with furosemide injection is the preferable technique for CT urography. In comparison with commonly used three-phase protocols, the dual-phase protocol significantly reduces radiation exposure dose without reduction in image quality.
Karády, Júlia; Panajotu, Alexisz; Kolossváry, Márton; Szilveszter, Bálint; Jermendy, Ádám L; Bartykowszki, Andrea; Károlyi, Mihály; Celeng, Csilla; Merkely, Béla; Maurovich-Horvat, Pál
2017-11-01
Contrast media (CM) extravasation is a well-known complication of CT angiography (CTA). Our prospective randomized control study aimed to assess whether a four-phasic CM administration protocol reduces the risk of extravasation compared to the routinely used three-phasic protocol in coronary CTA. Patients referred to coronary CTA due to suspected coronary artery disease were included in the study. All patients received 400 mg/ml iomeprol CM injected with dual-syringe automated injector. Patients were randomized into a three-phasic injection-protocol group, with a CM bolus of 85 ml followed by 40 ml of 75%:25% saline/CM mixture and 30 ml saline chaser bolus; and a four-phasic injection-protocol group, with a saline pacer bolus of 10 ml injected at a lower flow rate before the three-phasic protocol. 2,445 consecutive patients were enrolled (mean age 60.6 ± 12.1 years; females 43.6%). Overall rate of extravasation was 0.9% (23/2,445): 1.4% (17/1,229) in the three-phasic group and 0.5% (6/1,216) in the four-phasic group (p = 0.034). Four-phasic CM administration protocol is easy to implement in the clinical routine at no extra cost. The extravasation rate is reduced by 65% with the application of the four-phasic protocol compared to the three-phasic protocol in coronary CTA. • Four-phasic CM injection-protocol reduces extravasation rate by 65% compared to three-phasic. • The saline pacer bolus substantially reduces the risk of CM extravasation. • The implementation of four-phasic injection-protocol is at no cost.
Newgard, Craig D.; Nelson, Maria J.; Kampp, Michael; Saha, Somnath; Zive, Dana; Schmidt, Terri; Daya, Mohamud; Jui, Jonathan; Wittwer, Lynn; Warden, Craig; Sahni, Ritu; Stevens, Mark; Gorman, Kyle; Koenig, Karl; Gubler, Dean; Rosteck, Pontine; Lee, Jan; Hedges, Jerris R.
2011-01-01
Background The decision-making processes used for out-of-hospital trauma triage and hospital selection in regionalized trauma systems remain poorly understood. The objective of this study was to understand the process of field triage decision-making in an established trauma system. Methods We used a mixed methods approach, including EMS records to quantify triage decisions and reasons for hospital selection in a population-based, injury cohort (2006 - 2008), plus a focused ethnography to understand EMS cognitive reasoning in making triage decisions. The study included 10 EMS agencies providing service to a 4-county regional trauma system with 3 trauma centers and 13 non-trauma hospitals. For qualitative analyses, we conducted field observation and interviews with 35 EMS field providers and a round-table discussion with 40 EMS management personnel to generate an empirical model of out-of-hospital decision making in trauma triage. Results 64,190 injured patients were evaluated by EMS, of whom 56,444 (88.0%) were transported to acute care hospitals and 9,637 (17.1% of transports) were field trauma activations. For non-trauma activations, patient/family preference and proximity accounted for 78% of destination decisions. EMS provider judgment was cited in 36% of field trauma activations and was the sole criterion in 23% of trauma patients. The empirical model demonstrated that trauma triage is driven primarily by EMS provider “gut feeling” (judgment) and relies heavily on provider experience, mechanism of injury, and early visual cues at the scene. Conclusions Provider cognitive reasoning for field trauma triage is more heuristic than algorithmic and driven primarily by provider judgment, rather than specific triage criteria. PMID:21817971
Bornhöft, Lena; Larsson, Maria E H; Thorn, Jörgen
2015-01-01
Primary Care Triage is a patient sorting system used in some primary health care clinics (PHCCs) in Sweden where patients with musculoskeletal disorders (MSD) are triaged directly to physiotherapists. The purpose of this study was to investigate whether sorting/triaging patients seeking a PHCC for MSD directly to physiotherapists affects their utilization of medical services at the clinic for the MSD and to determine whether the effects of the triaging system vary for different sub-groups of patients. A retrospective case-control study design was used at two PHCCs. At the intervention clinic, 656 patients with MSD were initially triaged to physiotherapists. At the control clinic, 1673 patients were initially assessed by general practitioners (GPs). The main outcome measures were the number of patients continuing to visit GPs after the initial assessment, the number of patients receiving referrals to specialists/external examinations, doctors' notes for sick-leave or prescriptions for analgesics during one year, all for the original MSD. Significantly fewer patients triaged to physiotherapists required multiple GP visits for the MSD or received MSD-related referrals to specialists/external examinations, sick-leave recommendations or prescriptions during the following year compared to the GP-assessed group. This applies to all sub-groups except for the group with lower extremity disorders, which did not reach significance for either multiple GP visits or sick-leave recommendations. The reduced utilization of medical services by patients with MSD who were triaged to physiotherapists at a PHCC is likely due to altered management of MSD with initial assessment by physiotherapists.
Design and development of a mobile system for supporting emergency triage.
Michalowski, W; Slowinski, R; Wilk, S; Farion, K J; Pike, J; Rubin, S
2005-01-01
Our objective was to design and develop a mobile clinical decision support system for emergency triage of different acute pain presentations. The system should interact with existing hospital information systems, run on mobile computing devices (handheld computers) and be suitable for operation in weak-connectivity conditions (with unstable connections between mobile clients and a server). The MET (Mobile Emergency Triage) system was designed following an extended client-server architecture. The client component, responsible for triage decision support, is built as a knowledge-based system, with domain ontology separated from generic problem solving methods and used for the automatic creation of a user interface. The MET system is well suited for operation in the Emergency Department of a hospital. The system's external interactions are managed by the server, while the MET clients, running on handheld computers are used by clinicians for collecting clinical data and supporting triage at the bedside. The functionality of the MET client is distributed into specialized modules, responsible for triaging specific types of acute pain presentations. The modules are stored on the server, and on request they can be transferred and executed on the mobile clients. The modular design provides for easy extension of the system's functionality. A clinical trial of the MET system validated the appropriateness of the system's design, and proved the usefulness and acceptance of the system in clinical practice. The MET system captures the necessary hospital data, allows for entry of patient information, and provides triage support. By operating on handheld computers, it fits into the regular emergency department workflow without introducing any hindrances or disruptions. It supports triage anytime and anywhere, directly at the point of care, and also can be used as an electronic patient chart, facilitating structured data collection.
Cawthon, Peggy M.; Haslam, Jane; Fullman, Robin; Peters, Katherine W.; Black, Dennis; Ensrud, Kristine E.; Cummings, Steven R.; Orwoll, Eric S.; Barrett-Connor, Elizabeth; Marshall, Lynn; Steiger, Peter; Schousboe, John T.
2014-01-01
We describe the methods and reliability of radiographic vertebral fracture assessment in MrOS, a cohort of community dwelling men aged ≥65 yrs. Lateral spine radiographs were obtained at Visit 1 (2000-2) and 4.6 years later (Visit 2). Using a workflow tool (SpineAnalyzer™, Optasia Medical), a physician reader completed semi-quantitative (SQ) scoring. Prior to SQ scoring, technicians performed “triage” to reduce physician reader workload, whereby clearly normal spine images were eliminated from SQ scoring with all levels assumed to be SQ=0 (no fracture, “triage negative”); spine images with any possible fracture or abnormality were passed to the physician reader as “triage positive” images. Using a quality assurance sample of images (n=20 participants; 8 with baseline only and 12 with baseline and follow-up images) read multiple times, we calculated intra-reader kappa statistics and percent agreement for SQ scores. A subset of 494 participants' images were read regardless of triage classification to calculate the specificity and sensitivity of triage. Technically adequate images were available for 5958 of 5994 participants at Visit 1, and 4399 of 4423 participants at Visit 2. Triage identified 3215 (53.9%) participants with radiographs that required further evaluation by the physician reader. For prevalent fractures at Visit 1 (SQ≥1), intra-reader kappa statistics ranged from 0.79-0.92; percent agreement ranged from 96.9%-98.9%; sensitivity of the triage was 96.8% and specificity of triage was 46.3%. In conclusion, SQ scoring had excellent intra-rater reliability in our study. The triage process reduces expert reader workload without hindering the ability to identify vertebral fractures. PMID:25003811
Newgard, Craig D; Kampp, Michael; Nelson, Maria; Holmes, James F; Zive, Dana; Rea, Thomas; Bulger, Eileen M; Liao, Michael; Sherck, John; Hsia, Renee Y; Wang, N Ewen; Fleischman, Ross J; Barton, Erik D; Daya, Mohamud; Heineman, John; Kuppermann, Nathan
2012-05-01
"Emergency medical services (EMS) provider judgment" was recently added as a field triage criterion to the national guidelines, yet its predictive value and real world application remain unclear. We examine the use and independent predictive value of EMS provider judgment in identifying seriously injured persons. We analyzed a population-based retrospective cohort, supplemented by qualitative analysis, of injured children and adults evaluated and transported by 47 EMS agencies to 94 hospitals in five regions across the Western United States from 2006 to 2008. We used logistic regression models to evaluate the independent predictive value of EMS provider judgment for Injury Severity Score ≥ 16. EMS narratives were analyzed using qualitative methods to assess and compare common themes for each step in the triage algorithm, plus EMS provider judgment. 213,869 injured patients were evaluated and transported by EMS over the 3-year period, of whom 41,191 (19.3%) met at least one of the field triage criteria. EMS provider judgment was the most commonly used triage criterion (40.0% of all triage-positive patients; sole criterion in 21.4%). After accounting for other triage criteria and confounders, the adjusted odds ratio of Injury Severity Score ≥ 16 for EMS provider judgment was 1.23 (95% confidence interval, 1.03-1.47), although there was variability in predictive value across sites. Patients meeting EMS provider judgment had concerning clinical presentations qualitatively similar to those meeting mechanistic and other special considerations criteria. Among this multisite cohort of trauma patients, EMS provider judgment was the most commonly used field trauma triage criterion, independently associated with serious injury, and useful in identifying high-risk patients missed by other criteria. However, there was variability in predictive value between sites.
Automated Cervical Screening and Triage, Based on HPV Testing and Computer-Interpreted Cytology.
Yu, Kai; Hyun, Noorie; Fetterman, Barbara; Lorey, Thomas; Raine-Bennett, Tina R; Zhang, Han; Stamps, Robin E; Poitras, Nancy E; Wheeler, William; Befano, Brian; Gage, Julia C; Castle, Philip E; Wentzensen, Nicolas; Schiffman, Mark
2018-04-11
State-of-the-art cervical cancer prevention includes human papillomavirus (HPV) vaccination among adolescents and screening/treatment of cervical precancer (CIN3/AIS and, less strictly, CIN2) among adults. HPV testing provides sensitive detection of precancer but, to reduce overtreatment, secondary "triage" is needed to predict women at highest risk. Those with the highest-risk HPV types or abnormal cytology are commonly referred to colposcopy; however, expert cytology services are critically lacking in many regions. To permit completely automatable cervical screening/triage, we designed and validated a novel triage method, a cytologic risk score algorithm based on computer-scanned liquid-based slide features (FocalPoint, BD, Burlington, NC). We compared it with abnormal cytology in predicting precancer among 1839 women testing HPV positive (HC2, Qiagen, Germantown, MD) in 2010 at Kaiser Permanente Northern California (KPNC). Precancer outcomes were ascertained by record linkage. As additional validation, we compared the algorithm prospectively with cytology results among 243 807 women screened at KPNC (2016-2017). All statistical tests were two-sided. Among HPV-positive women, the algorithm matched the triage performance of abnormal cytology. Combined with HPV16/18/45 typing (Onclarity, BD, Sparks, MD), the automatable strategy referred 91.7% of HPV-positive CIN3/AIS cases to immediate colposcopy while deferring 38.4% of all HPV-positive women to one-year retesting (compared with 89.1% and 37.4%, respectively, for typing and cytology triage). In the 2016-2017 validation, the predicted risk scores strongly correlated with cytology (P < .001). High-quality cervical screening and triage performance is achievable using this completely automated approach. Automated technology could permit extension of high-quality cervical screening/triage coverage to currently underserved regions.
A quality improvement project to improve early sepsis care in the emergency department.
Gatewood, Medley O'Keefe; Wemple, Matthew; Greco, Sheryl; Kritek, Patricia A; Durvasula, Raghu
2015-12-01
Sepsis causes substantial morbidity and mortality in hospitalised patients. Although many studies describe the use of protocols in the management of patients with severe sepsis and septic shock, few have addressed emergency department (ED) screening and management for patients initially presenting with uncomplicated sepsis (ie, patients without organ failure or hypotension). A quality improvement task force at a large, quaternary care referral hospital sought to develop a protocol focusing on early identification of patients with uncomplicated sepsis, in addition to severe sepsis and septic shock. The three-tiered intervention consisted of (1) a nurse-driven screening tool and management protocol to identify and initiate early treatment of patients with sepsis, (2) a computer-assisted screening algorithm that generated a 'Sepsis Alert' pop-up screen in the electronic medical record for treating clinical healthcare providers and (3) automated suggested sepsis-specific order sets for initial workup and resuscitation, antibiotic selection and goal-directed therapy. A before and after retrospective cohort study was undertaken to determine the intervention's impact on compliance with recommended sepsis management, including serum lactate measured in the ED, 2 L of intravenous fluid administered within 2 h of triage, antibiotics administered within 3 h of triage and blood cultures drawn before antibiotic administration. Mortality rates for patients in the ED with a sepsis-designated ICD-9 code present on admission were also analysed. Overall bundle compliance increased by 154%, from 28% at baseline to 71% in the last quarter of the study (p<0.001). Bundle, antibiotic and intravenous fluid compliance all increased significantly after launch of the sepsis initiative (eg, bundle and intravenous fluid compliance increased by 74% and 54%, respectively; p<0.001). Bundle and antibiotic compliance both showed further significant increases after implementation of suggested order sets (31% and 25% increases, respectively; p<0.001). The mortality rate for patients in the ED admitted with sepsis was 13.3% before implementation and fell to 11.1% after (p=0.230); mortality in the last two quarters of the study was 9.3% (p=0.107). The new protocol demonstrates that early screening interventions can lead to expedited delivery of care to patients with sepsis in the ED and could serve as a model for other facilities. Mortality was not significantly improved by our intervention, which included patients with uncomplicated sepsis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Shifting Gears: Triage and Traffic in Urban India.
Solomon, Harris
2017-09-01
While studies of triage in clinical medical literature tend to focus on the knowledge required to carry out sorting, this article details the spatial features of triage. It is based on participation observation of traffic-related injuries in a Mumbai hospital casualty ward. It pays close attention to movement, specifically to adjustments, which include moving bodies, changes in treatment priority, and interruptions in care. The article draws on several ethnographic cases of injury and its aftermath that gather and separate patients, kin, and bystanders, all while a triage medical authority is charged with sorting them out. I argue that attention must be paid to differences in movement, which can be overlooked if medical decision-making is taken to be a static verdict. The explanatory significance of this distinction between adjustment and adjudication is a more nuanced understanding of triage as an iterative, spatial process. © 2017 by the American Anthropological Association.
Documentation and tagging of casualties in multiple casualty incidents.
Garner, Alan
2003-01-01
The use of triage tags is widely advocated as a tool to improve the management of multiple casualty incident scenes. However, there are no published reports to suggest that triage tags have improved the management of incidents involving more than 24 persons, and a number of reports have detailed problems associated with triage tag use. Alternative systems of scene management such as geographical triage have been successfully used in very large incidents, and are recommended as an alternative to triage tags. Documentation cards attached to casualties may be of use in situations where casualties will pass through an extended evacuation chain, and clear labels for deceased casualties are of benefit as they discourage repeat assessments. Adoption of an evidence-based approach to multiple casualty incident scene management will require a paradigm shift in the thinking of ambulance services. A broad-based educational approach that encourages critical reappraisal of existing procedures is recommended.
A descriptive study of women presenting to an obstetric triage unit with no prenatal care.
Knight, Erin; Morris, Margaret; Heaman, Maureen
2014-03-01
To describe women presenting to an obstetric triage unit with no prenatal care (PNC), to identify gaps in care, and to compare care provided to World Health Organization (WHO) standards. We reviewed the charts of women who gave birth at Women's Hospital in Winnipeg and were discharged between April 1, 2008, and March 31, 2011, and identified those whose charts were coded with ICD-10 code Z35.3 (inadequate PNC) or who had fewer than 2 PNC visits. Three hundred eighty-two charts were identified, and sociodemographic characteristics, PNC history, investigations, and pregnancy outcomes were recorded. The care provided was compared with WHO guidelines. One hundred nine women presented to the obstetric triage unit with no PNC; 96 (88.1%) were in the third trimester. Only 39 women (35.8%) received subsequent PNC, with care falling short of WHO standards. Gaps in PNC included missing time-sensitive screening tests, mid-stream urine culture, and Chlamydia and gonorrhea testing. The mean maternal age was 26.1 years, and 93 women (85.3%) were multigravidas. More than one half of the women (51.4%) were involved with Child and Family Services, 64.2% smoked, 33.0% drank alcohol, and 32.1% used illicit drugs during pregnancy. Two thirds of the women (66.2%) lived in inner-city Winnipeg. Only 63.0% of neonates showed growth appropriate for gestational age. Two pregnancies ended in stillbirth; there was one neonatal death, and over one third of the births were preterm. Most women who present with no PNC do so late in pregnancy, proceed to deliver with little or no additional PNC, and have high rates of adverse outcomes. Thus, efforts to improve PNC must focus on facilitating earlier entry into care. This would also improve compliance with WHO guidelines for continuing care. Treatment protocols could improve gaps in obtaining urine culture and in Chlamydia and gonorrhea testing.
Target coverage in image-guided stereotactic body radiotherapy of liver tumors.
Wunderink, Wouter; Méndez Romero, Alejandra; Vásquez Osorio, Eliana M; de Boer, Hans C J; Brandwijk, René P; Levendag, Peter C; Heijmen, Ben J M
2007-05-01
To determine the effect of image-guided procedures (with computed tomography [CT] and electronic portal images before each treatment fraction) on target coverage in stereotactic body radiotherapy for liver patients using a stereotactic body frame (SBF) and abdominal compression. CT guidance was used to correct for day-to-day variations in the tumor's mean position in the SBF. By retrospectively evaluating 57 treatment sessions, tumor coverage, as obtained with the clinically applied CT-guided protocol, was compared with that of alternative procedures. The internal target volume-plus (ITV(+)) was introduced to explicitly include uncertainties in tumor delineations resulting from CT-imaging artifacts caused by residual respiratory motion. Tumor coverage was defined as the volume overlap of the ITV(+), derived from a tumor delineated in a treatment CT scan, and the planning target volume. Patient stability in the SBF, after acquisition of the treatment CT scan, was evaluated by measuring the displacement of the bony anatomy in the electronic portal images relative to CT. Application of our clinical protocol (with setup corrections following from manual measurements of the distances between the contours of the planning target volume and the daily clinical target volume in three orthogonal planes, multiple two-dimensional) increased the frequency of nearly full (> or = 99%) ITV(+) coverage to 77% compared with 63% without setup correction. An automated three-dimensional method further improved the frequency to 96%. Patient displacements in the SBF were generally small (< or = 2 mm, 1 standard deviation), but large craniocaudal displacements (maximal 7.2 mm) were occasionally observed. Daily, CT-assisted patient setup may substantially improve tumor coverage, especially with the automated three-dimensional procedure. In the present treatment design, patient stability in the SBF should be verified with portal imaging.
NASA Astrophysics Data System (ADS)
Li, Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Frush, Donald P.
2010-04-01
Radiation-dose awareness and optimization in CT can greatly benefit from a dosereporting system that provides radiation dose and cancer risk estimates specific to each patient and each CT examination. Recently, we reported a method for estimating patientspecific dose from pediatric chest CT. The purpose of this study is to extend that effort to patient-specific risk estimation and to a population of pediatric CT patients. Our study included thirty pediatric CT patients (16 males and 14 females; 0-16 years old), for whom full-body computer models were recently created based on the patients' clinical CT data. Using a validated Monte Carlo program, organ dose received by the thirty patients from a chest scan protocol (LightSpeed VCT, 120 kVp, 1.375 pitch, 40-mm collimation, pediatric body scan field-of-view) was simulated and used to estimate patient-specific effective dose. Risks of cancer incidence were calculated for radiosensitive organs using gender-, age-, and tissue-specific risk coefficients and were used to derive patientspecific effective risk. The thirty patients had normalized effective dose of 3.7-10.4 mSv/100 mAs and normalized effective risk of 0.5-5.8 cases/1000 exposed persons/100 mAs. Normalized lung dose and risk of lung cancer correlated strongly with average chest diameter (correlation coefficient: r = -0.98 to -0.99). Normalized effective risk also correlated strongly with average chest diameter (r = -0.97 to -0.98). These strong correlations can be used to estimate patient-specific dose and risk prior to or after an imaging study to potentially guide healthcare providers in justifying CT examinations and to guide individualized protocol design and optimization.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bache, S; Loyer, E; Stauduhar, P
2015-06-15
Purpose: To quantify and compare the noise properties between two GE CT models-the Discovery CT750 HD (aka HD750) and LightSpeed VCT, with the overall goal of assessing the impact in clinical diagnostic practice. Methods: Daily QC data from a fleet of 9 CT scanners currently in clinical use were investigated – 5 HD750 and 4 VCT (over 600 total acquisitions for each scanner). A standard GE QC phantom was scanned daily using two sets of scan parameters with each scanner over 1 year. Water CT number and standard deviation were recorded from the image of water section of the QCmore » phantom. The standard GE QC scan parameters (Pitch = 0.516, 120kVp, 0.4s, 335mA, Small Body SFOV, 5mm thickness) and an in-house developed protocol (Axial, 120kVp, 1.0s, 240mA, Head SFOV, 5mm thickness) were used, with Standard reconstruction algorithm. Noise was measured as the standard deviation in the center of the water phantom image. Inter-model noise distributions and tube output in mR/mAs were compared to assess any relative differences in noise properties. Results: With the in-house protocols, average noise for the five HD750 scanners was ∼9% higher than the VCT scanners (5.8 vs 5.3). For the GE QC protocol, average noise with the HD750 scanners was ∼11% higher than with the VCT scanners (4.8 vs 4.3). This discrepancy in noise between the two models was found despite the tube output in mR/mAs being comparable with the HD750 scanners only having ∼4% lower output (8.0 vs 8.3 mR/mAs). Conclusion: Using identical scan protocols, average noise in images from the HD750 group was higher than that from the VCT group. This confirms feedback from an institutional radiologist’s feedback regarding grainier patient images from HD750 scanners. Further investigation is warranted to assess the noise texture and distribution, as well as clinical impact.« less
Evaluation of various active surveillance protocols in prostate cancer.
Yılmaz, Kayhan; Karadeniz, Tahir; Ozkaptan, Orkunt; Yilanoglu, Oguz
2014-06-30
This study aims to investigate whether pathology results obtained by radical retropubic prostatectomy (RRP) were correlated with active surveillance (AS) criteria defined by Klotz, Soloway and D'Amico. In our clinic we evaluated 211 patients with diagnosis of localized prostate cancer who underwent RRP between 2007 and 2012. AS criteria defined by Soloway (cT ≤ T2, PSA ≤ 15 ng/dl, Gleason ≤ 6), Klotz (cT1c-T2a; if age ≥ 70 PSA ≤ 15 ng/dl, if age < 70 PSA ≤ 10 ng/dl; if age ≥ 70 Gleason ≤ 7(3+4), if age < 70 Gleason ≤ 6) and D'Amico (cT1c-T2a, PSA ≤ 10 ng/dl, Gleason ≤ 6) were used in our study. Pathological stages and Gleason scores were evaluated with coherence to AS protocols, mis-staging rates, biochemical recurrence (BC) of the mis-staged patients and death due to prostate cancer Data was analyzed using NCSS 2007 & PASS 2008 Statistical Software (Utah, USA). Chi square test and Mann-Whitney U test were applied for analyzing qualitative data. Significance was determined as p < 0.05. 137 (64.9%) patients were coherent with Soloway AS criteria, 118 (55.9%) with Klotz AS criteria and 108 (51.1%) with D'Amico AS criteria. Histopathological results of the patients grouped according to Soloway, Klotz and D'Amico AS protocols showed high stage prostate cancer in 40 (29.2%), 32 (27%) and 27 (24.9%) patients, respectively. High grade prostate cancer rates in Soloway, Klotz, D'Amico groups were 55 (40.2%), 46 (38%) and 39 (36.1%); respectively. Misstaging rates of Soloway, Klotz and D'Amico AS protocols were determined as 65 (47.4%), 54 (45.5%) and 46 (42.5%), respectively. In the Soloway group BC rate was 21.9% in those with high stages. Relation between BC and high stage was found to be statistically significant (p < 0.05). Misstaging rates were relatively high in the three groups and there was no difference between the three groups in BC rates. Randomized studies with adequate follow up are needed.
Gilbert, John W; Johnson, Kevin M; Larkin, Gregory L; Moore, Christopher L
2012-07-01
To estimate recent trends in CT/MRI utilisation among patients seeking emergency care for atraumatic headache in the USA and to identify factors associated with a diagnosis of significant intracranial pathology (ICP) in these patients. Data were obtained from the USA National Hospital Ambulatory Medical Care Survey of emergency department (ED) visits between 1998 and 2008. A cohort of atraumatic headache-related visits were identified using preassigned 'reason-for-visit' codes. Sample visits were weighted to provide national estimates. Between 1998 and 2008 the percentage of patients presenting to the ED with atraumatic headache who underwent imaging increased from 12.5% to 31.0% (p < 0.01) while the prevalence of ICP among those visits decreased from 10.1% to 3.5% (p < 0.05). The length of stay in the ED was 4.6 h (95% CI 4.4 to 4.8) for patients with headache who received imaging compared with 2.7 (95% CI 2.6 to 2.9) for those who did not. Of 18 factors evaluated in patients with headache, 10 were associated with a significantly increased odds of an ICP diagnosis: age ≥ 50 years, arrival by ambulance, triage immediacy <15 min, systolic blood pressure ≥ 160 mm Hg or diastolic blood pressure ≥ 100 mm Hg and disturbance in sensation, vision, speech or motor function including neurological weakness. The use of CT/MRI for evaluation of atraumatic headache increased dramatically in EDs in the USA between 1998 and 2008. The prevalence of ICP among patients who received CT/MRI declined concurrently, suggesting a role for clinical decision support to guide more judicious use of imaging.
Boos, J; Meineke, A; Rubbert, C; Heusch, P; Lanzman, R S; Aissa, J; Antoch, G; Kröpil, P
2016-03-01
To implement automated CT dose data monitoring using the DICOM-Structured Report (DICOM-SR) in order to monitor dose-related CT data in regard to national diagnostic reference levels (DRLs). We used a novel in-house co-developed software tool based on the DICOM-SR to automatically monitor dose-related data from CT examinations. The DICOM-SR for each CT examination performed between 09/2011 and 03/2015 was automatically anonymized and sent from the CT scanners to a cloud server. Data was automatically analyzed in accordance with body region, patient age and corresponding DRL for volumetric computed tomography dose index (CTDIvol) and dose length product (DLP). Data of 36,523 examinations (131,527 scan series) performed on three different CT scanners and one PET/CT were analyzed. The overall mean CTDIvol and DLP were 51.3% and 52.8% of the national DRLs, respectively. CTDIvol and DLP reached 43.8% and 43.1% for abdominal CT (n=10,590), 66.6% and 69.6% for cranial CT (n=16,098) and 37.8% and 44.0% for chest CT (n=10,387) of the compared national DRLs, respectively. Overall, the CTDIvol exceeded national DRLs in 1.9% of the examinations, while the DLP exceeded national DRLs in 2.9% of the examinations. Between different CT protocols of the same body region, radiation exposure varied up to 50% of the DRLs. The implemented cloud-based CT dose monitoring based on the DICOM-SR enables automated benchmarking in regard to national DRLs. Overall the local dose exposure from CT reached approximately 50% of these DRLs indicating that DRL actualization as well as protocol-specific DRLs are desirable. The cloud-based approach enables multi-center dose monitoring and offers great potential to further optimize radiation exposure in radiological departments. • The newly developed software based on the DICOM-Structured Report enables large-scale cloud-based CT dose monitoring • The implemented software solution enables automated benchmarking in regard to national DRLs • The local radiation exposure from CT reached approximately 50 % of the national DRLs • The cloud-based approach offers great potential for multi-center dose analysis. © Georg Thieme Verlag KG Stuttgart · New York.