Using Patient Case Video Vignettes to Improve Students' Understanding of Cross-cultural Communication.

PubMed

Arif, Sally; Cryder, Brian; Mazan, Jennifer; Quiñones-Boex, Ana; Cyganska, Angelika

2017-04-01

Objective. To develop, implement, and assess whether simulated patient case videos improve students' understanding of and attitudes toward cross-cultural communication in health care. Design. Third-year pharmacy students (N=159) in a health care communications course participated in a one-hour lecture and two-hour workshop on the topic of cross-cultural communication. Three simulated pharmacist-patient case vignettes highlighting cross-cultural communication barriers, the role of active listening, appropriate use of medical interpreters, and useful models to overcome communication barriers were viewed and discussed in groups of 20 students during the workshop. Assessment. A pre-lecture and post-workshop assessed the effect on students' understanding of and attitudes toward cross-cultural communication. Understanding of cross-cultural communication concepts increased significantly, as did comfort level with providing cross-cultural care. Conclusion. Use of simulated patient case videos in conjunction with an interactive workshop improved pharmacy students' understanding of and comfort level with cross-cultural communication skills and can be useful tools for cultural competency training in the curriculum.

Simulated procedure rehearsal is more effective than a preoperative generic warm-up for endovascular procedures.

PubMed

Willaert, Willem I M; Aggarwal, Rajesh; Daruwalla, Farhad; Van Herzeele, Isabelle; Darzi, Ara W; Vermassen, Frank E; Cheshire, Nicholas J

2012-06-01

Patient-specific simulated rehearsal (PsR) of a carotid artery stenting procedure (CAS) enables the interventionalist to rehearse the case before performing the procedure on the actual patient by incorporating patient-specific computed tomographic data into the simulation software. This study aimed to evaluate whether PsR of a CAS procedure can enhance the operative performance versus a virtual reality (VR) generic CAS warm-up procedure or no preparation at all. During a 10-session cognitive/technical VR course, medical residents were trained in CAS. Thereafter, in a randomized crossover study, each participant performed a patient-specific CAS case 3 times on the simulator, preceded by 3 different tasks: a PsR, a generic case, or no preparation. Technical performances were assessed using simulator-based metrics and expert-based ratings. Twenty medical residents (surgery, cardiology, radiology) were recruited. Training plateaus were observed after 10 sessions for all participants. Performances were significantly better after PsR than after a generic warm-up or no warm-up for total procedure time (16.3 ± 0.6 vs 19.7 ± 1.0 vs 20.9 ± 1.1 minutes, P = 0.001) and fluoroscopy time (9.3 ± 0.1 vs 11.2 ± 0.6 vs 11.2 ± 0.5 minutes, P = 0.022) but did not influence contrast volume or number of roadmaps used during the "real" case. PsR significantly improved the quality of performance as measured by the expert-based ratings (scores 28 vs 25 vs 25, P = 0.020). Patient-specific simulated rehearsal of a CAS procedure significantly improves operative performance, compared to a generic VR warm-up or no warm-up. This technology requires further investigation with respect to improved outcomes on patients in the clinical setting.

Development, implementation and pilot evaluation of a Web-based Virtual Patient Case Simulation environment – Web-SP

PubMed Central

Zary, Nabil; Johnson, Gunilla; Boberg, Jonas; Fors, Uno GH

2006-01-01

Background The Web-based Simulation of Patients (Web-SP) project was initiated in order to facilitate the use of realistic and interactive virtual patients (VP) in medicine and healthcare education. Web-SP focuses on moving beyond the technology savvy teachers, when integrating simulation-based education into health sciences curricula, by making the creation and use of virtual patients easier. The project strives to provide a common generic platform for design/creation, management, evaluation and sharing of web-based virtual patients. The aim of this study was to evaluate if it was possible to develop a web-based virtual patient case simulation environment where the entire case authoring process might be handled by teachers and which would be flexible enough to be used in different healthcare disciplines. Results The Web-SP system was constructed to support easy authoring, management and presentation of virtual patient cases. The case authoring environment was found to facilitate for teachers to create full-fledged patient cases without the assistance of computer specialists. Web-SP was successfully implemented at several universities by taking into account key factors such as cost, access, security, scalability and flexibility. Pilot evaluations in medical, dentistry and pharmacy courses shows that students regarded Web-SP as easy to use, engaging and to be of educational value. Cases adapted for all three disciplines were judged to be of significant educational value by the course leaders. Conclusion The Web-SP system seems to fulfil the aim of providing a common generic platform for creation, management and evaluation of web-based virtual patient cases. The responses regarding the authoring environment indicated that the system might be user-friendly enough to appeal to a majority of the academic staff. In terms of implementation strengths, Web-SP seems to fulfil most needs from course directors and teachers from various educational institutions and disciplines. The system is currently in use or under implementation in several healthcare disciplines at more than ten universities worldwide. Future aims include structuring the exchange of cases between teachers and academic institutions by building a VP library function. We intend to follow up the positive results presented in this paper with other studies looking at the learning outcomes, critical thinking and patient management. Studying the potential of Web-SP as an assessment tool will also be performed. More information about Web-SP: PMID:16504041

Development, implementation and pilot evaluation of a Web-based Virtual Patient Case Simulation environment--Web-SP.

PubMed

Zary, Nabil; Johnson, Gunilla; Boberg, Jonas; Fors, Uno G H

2006-02-21

The Web-based Simulation of Patients (Web-SP) project was initiated in order to facilitate the use of realistic and interactive virtual patients (VP) in medicine and healthcare education. Web-SP focuses on moving beyond the technology savvy teachers, when integrating simulation-based education into health sciences curricula, by making the creation and use of virtual patients easier. The project strives to provide a common generic platform for design/creation, management, evaluation and sharing of web-based virtual patients. The aim of this study was to evaluate if it was possible to develop a web-based virtual patient case simulation environment where the entire case authoring process might be handled by teachers and which would be flexible enough to be used in different healthcare disciplines. The Web-SP system was constructed to support easy authoring, management and presentation of virtual patient cases. The case authoring environment was found to facilitate for teachers to create full-fledged patient cases without the assistance of computer specialists. Web-SP was successfully implemented at several universities by taking into account key factors such as cost, access, security, scalability and flexibility. Pilot evaluations in medical, dentistry and pharmacy courses shows that students regarded Web-SP as easy to use, engaging and to be of educational value. Cases adapted for all three disciplines were judged to be of significant educational value by the course leaders. The Web-SP system seems to fulfil the aim of providing a common generic platform for creation, management and evaluation of web-based virtual patient cases. The responses regarding the authoring environment indicated that the system might be user-friendly enough to appeal to a majority of the academic staff. In terms of implementation strengths, Web-SP seems to fulfil most needs from course directors and teachers from various educational institutions and disciplines. The system is currently in use or under implementation in several healthcare disciplines at more than ten universities worldwide. Future aims include structuring the exchange of cases between teachers and academic institutions by building a VP library function. We intend to follow up the positive results presented in this paper with other studies looking at the learning outcomes, critical thinking and patient management. Studying the potential of Web-SP as an assessment tool will also be performed. More information about Web-SP: http://websp.lime.ki.se.

Mixed virtual reality simulation--taking endoscopic simulation one step further.

PubMed

Courteille, O; Felländer-Tsai, L; Hedman, L; Kjellin, A; Enochsson, L; Lindgren, G; Fors, U

2011-01-01

This pilot study aimed to assess medical students' appraisals of a "mixed" virtual reality simulation for endoscopic surgery (with a virtual patient case in addition to a virtual colonoscopy) as well as the impact of this simulation set-up on students' performance. Findings indicate that virtual patients can enhance contextualization of simulated endoscopy and thus facilitate an authentic learning environment, which is important in order to increase motivation.

A tool for assessing case history and feedback skills in audiology students working with simulated patients.

PubMed

Hughes, Jane; Wilson, Wayne J; MacBean, Naomi; Hill, Anne E

2016-12-01

To develop a tool for assessing audiology students taking a case history and giving feedback with simulated patients (SP). Single observation, single group design. Twenty-four first-year audiology students, five simulated patients, two clinical educators, and three evaluators. The Audiology Simulated Patient Interview Rating Scale (ASPIRS) was developed consisting of six items assessing specific clinical skills, non-verbal communication, verbal communication, interpersonal skills, interviewing skills, and professional practice skills. These items are applied once for taking a case history and again for giving feedback. The ASPIRS showed very high internal consistency (α = 0.91-0.97; mean inter-item r = 0.64-0.85) and fair-to-moderate agreement between evaluators (29.2-54.2% exact and 79.2-100% near agreement; κ weighted up to 0.60). It also showed fair-to-moderate absolute agreement amongst evaluators for single evaluator scores (intraclass correlation coefficient [ICC] r = 0.35-0.59) and substantial consistency of agreement amongst evaluators for three-evaluator averaged scores (ICC r = 0.62-0.81). Factor analysis showed the ASPIRS' 12 items fell into two components, one containing all feedback items and one containing all case history items. The ASPIRS shows promise as the first published tool for assessing audiology students taking a case history and giving feedback with an SP.

Computer Simulation in Mass Emergency and Disaster Response: An Evaluation of Its Effectiveness as a Tool for Demonstrating Strategic Competency in Emergency Department Medical Responders

ERIC Educational Resources Information Center

O'Reilly, Daniel J.

2011-01-01

This study examined the capability of computer simulation as a tool for assessing the strategic competency of emergency department nurses as they responded to authentically computer simulated biohazard-exposed patient case studies. Thirty registered nurses from a large, urban hospital completed a series of computer-simulated case studies of…

Using Patient Case Video Vignettes to Improve Students’ Understanding of Cross-cultural Communication

PubMed Central

Cryder, Brian; Mazan, Jennifer; Quiñones-Boex, Ana; Cyganska, Angelika

2017-01-01

Objective. To develop, implement, and assess whether simulated patient case videos improve students’ understanding of and attitudes toward cross-cultural communication in health care. Design. Third-year pharmacy students (N=159) in a health care communications course participated in a one-hour lecture and two-hour workshop on the topic of cross-cultural communication. Three simulated pharmacist-patient case vignettes highlighting cross-cultural communication barriers, the role of active listening, appropriate use of medical interpreters, and useful models to overcome communication barriers were viewed and discussed in groups of 20 students during the workshop. Assessment. A pre-lecture and post-workshop assessed the effect on students’ understanding of and attitudes toward cross-cultural communication. Understanding of cross-cultural communication concepts increased significantly, as did comfort level with providing cross-cultural care. Conclusion. Use of simulated patient case videos in conjunction with an interactive workshop improved pharmacy students' understanding of and comfort level with cross-cultural communication skills and can be useful tools for cultural competency training in the curriculum. PMID:28496276

Modelling approaches: the case of schizophrenia.

PubMed

Heeg, Bart M S; Damen, Joep; Buskens, Erik; Caleo, Sue; de Charro, Frank; van Hout, Ben A

2008-01-01

Schizophrenia is a chronic disease characterized by periods of relative stability interrupted by acute episodes (or relapses). The course of the disease may vary considerably between patients. Patient histories show considerable inter- and even intra-individual variability. We provide a critical assessment of the advantages and disadvantages of three modelling techniques that have been used in schizophrenia: decision trees, (cohort and micro-simulation) Markov models and discrete event simulation models. These modelling techniques are compared in terms of building time, data requirements, medico-scientific experience, simulation time, clinical representation, and their ability to deal with patient heterogeneity, the timing of events, prior events, patient interaction, interaction between co-variates and variability (first-order uncertainty). We note that, depending on the research question, the optimal modelling approach should be selected based on the expected differences between the comparators, the number of co-variates, the number of patient subgroups, the interactions between co-variates, and simulation time. Finally, it is argued that in case micro-simulation is required for the cost-effectiveness analysis of schizophrenia treatments, a discrete event simulation model is best suited to accurately capture all of the relevant interdependencies in this chronic, highly heterogeneous disease with limited long-term follow-up data.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, H; Manning, M; Sintay, B

Purpose: Tumor motion in lung SBRT is typically managed by creating an internal target volume (ITV) based on 4D-CT information. Another option, which may reduce lung dose and imaging artifact, is to use a breath hold (BH) during simulation and delivery. Here we evaluate the reproducibility of tumor position at repeated BH using a newly released spirometry system. Methods: Three patients underwent multiple BH CT’s at simulation. All patients underwent a BH cone beam CT (CBCT) prior to each treatment. All image sets were registered to a patient’s first simulation CT based on local bony anatomy. The gross tumor volumemore » (GTV), and the diaphragm or the apex of the lung were contoured on the first image set and expanded in 1 mm increments until the GTVs and diaphragms on all image sets were included inside an expanded structure. The GTV and diaphragm margins necessary to encompass the structures were recorded. Results: The first patient underwent 2 BH CT’s and fluoroscopy at simulation, the remaining patients underwent 3 BH CT’s at simulation. In all cases the GTV’s remained within 1 mm expansions and the diaphragms remained within 2 mm expansions on repeat scans. Each patient underwent 3 daily BH CBCT’s. In all cases the GTV’s remained within a 2 mm expansions, and the diaphragms (or lung apex in one case) remained within 2 mm expansions at daily BH imaging. Conclusions: These case studies demonstrate spirometry as an effective tool for limiting tumor motion (and imaging artifact) and facilitating reproducible tumor positioning over multiple set-ups and BH’s. This work was partially supported by Qfix.« less

Audio Taping Simulated Patient Encounters in Community Pharmacy to Enhance the Reliability of Assessments

PubMed Central

Werner, Joel Benjamin

2008-01-01

Objectives To assess whether audio taping simulated patient interactions can improve the reliability of manually documented data and result in more accurate assessments. Methods Over a 3-month period, 1340 simulated patient visits were made to community pharmacies. Following the encounters, data gathered by the simulated patient were relayed to a coordinator who completed a rating form. Data recorded on the forms were later compared to an audiotape of the interaction. Corrections were tallied and reasons for making them were coded. Results Approximately 10% of cases required corrections, resulting in a 10%-20% modification in the pharmacy's total score. The difference between postcorrection and precorrection scores was significant. Conclusions Audio taping simulated patient visits enhances data integrity. Most corrections were required because of the simulated patients' poor recall abilities. PMID:19325956

Computational Simulations of Inferior Vena Cava (IVC) Filter Placement and Hemodynamics in Patient-Specific Geometries

NASA Astrophysics Data System (ADS)

Aycock, Kenneth; Sastry, Shankar; Kim, Jibum; Shontz, Suzanne; Campbell, Robert; Manning, Keefe; Lynch, Frank; Craven, Brent

2013-11-01

A computational methodology for simulating inferior vena cava (IVC) filter placement and IVC hemodynamics was developed and tested on two patient-specific IVC geometries: a left-sided IVC, and an IVC with a retroaortic left renal vein. Virtual IVC filter placement was performed with finite element analysis (FEA) using non-linear material models and contact modeling, yielding maximum vein displacements of approximately 10% of the IVC diameters. Blood flow was then simulated using computational fluid dynamics (CFD) with four cases for each patient IVC: 1) an IVC only, 2) an IVC with a placed filter, 3) an IVC with a placed filter and a model embolus, all at resting flow conditions, and 4) an IVC with a placed filter and a model embolus at exercise flow conditions. Significant hemodynamic differences were observed between the two patient IVCs, with the development of a right-sided jet (all cases) and a larger stagnation region (cases 3-4) in the left-sided IVC. These results support further investigation of the effects of IVC filter placement on a patient-specific basis.

Virtual patient care: an interprofessional education approach for physician assistant, physical therapy and occupational therapy students.

PubMed

Shoemaker, Michael J; Platko, Christina M; Cleghorn, Susan M; Booth, Andrew

2014-07-01

The purpose of this retrospective qualitative case report is to describe how a case-based, virtual patient interprofessional education (IPE) simulation activity was utilized to achieve physician assistant (PA), physical therapy (PT) and occupational therapy (OT) student IPE learning outcomes. Following completion of a virtual patient case, 30 PA, 46 PT and 24 OT students were required to develop a comprehensive, written treatment plan and respond to reflective questions. A qualitative analysis of the submitted written assignment was used to determine whether IPE learning objectives were met. Student responses revealed three themes that supported the learning objectives of the IPE experience: benefits of collaborative care, role clarification and relevance of the IPE experience for future practice. A case-based, IPE simulation activity for physician assistant and rehabilitation students using a computerized virtual patient software program effectively facilitated achievement of the IPE learning objectives, including development of greater student awareness of other professions and ways in which collaborative patient care can be provided.

Use of clinical simulations for patient education: targeting an untapped audience.

PubMed

Siwe, Karin; Berterö, Carina; Pugh, Carla; Wijma, Barbro

2009-01-01

In most cases, the health professional has been the target for simulation based learning curricula. We have developed a simulation based curriculum for patient education. In our curriculum lay-women learn how to perform the clinical female pelvic examination using a manikin-based trainer. Learner assessments show that prior negative expectations turned into positive expectations regarding future pelvic examinations.

Misdiagnosis of obstetrical cases and the clinical and cost consequences to patients: a cross-sectional study of urban providers in the Philippines

PubMed Central

Shimkhada, Riti; Solon, Orville; Tamondong-Lachica, Diana; Peabody, John W.

2016-01-01

Background Misdiagnosis may be a significant and under-recognized quality of care problem. In birthing facilities located in anurban Philippine setting, we investigated the diagnostic accuracy for three obstetric conditions: cephalopelvic disproportion (CPD), post-partum hemorrhage (PPH), and pre-eclampsia. Design Identical simulated cases were used to measure diagnostic accuracy for every provider (n=103). We linked misdiagnosis – identified by the simulated cases – to obstetrical complications of the patients at the participating facilities. Patient-level data on health outcomes and costs were obtained from medical records and follow-home in-person interviews. Results The prevalence of misdiagnosis among obstetric providers was 29.8% overall, 25% for CPD, 33% for PPH, and 31% for pre-eclampsia. Linking provider decision-making to patients, we found those who misdiagnosed the simulated cases were more likely to have patients with a complication (OR 2.96; 95% CI 1.39–3.77) compared with those who did not misdiagnose. Complicated patients were significantly less likely to be referred to a hospital immediately, were more likely to be readmitted to a hospital after delivery, had significantly higher medical costs, and lost more income than non-complicated patients. Conclusion Diagnosis is arguably the most important task a clinician performs because it determines the subsequent course of evaluation and treatment, with the direct and indirect costs of diagnostic error, placing large financial burdens on the patient. PMID:27987297

Expanding MIRAgel scleral buckle simulating an orbital tumor in four cases.

PubMed

Shields, Carol L; Demirci, Hakan; Marr, Brian P; Mashayekhi, Arman; Materin, Miguel A; Shields, Jerry A

2005-01-01

To describe four patients with an enlarging orbital mass from a swollen MIRAgel scleral buckle that simulated an orbital neoplasm. In a retrospective, single-center case series at the Ocular Oncology Service at Wills Eye Hospital of Thomas Jefferson University, 4 eyes of 4 patients were referred for evaluation and treatment of a suspected orbital tumor. The initial presenting features were orbital mass (case 1), strabismus (case 2), and conjunctival mass with orbital extension (cases 3 and 4). Each patient vaguely recalled previous uncomplicated retinal detachment surgery 12 to 20 years earlier. Confirmation of the buckling implant material was made with the retina surgeon in 3 cases. A nontender, forniceal conjunctival mass, deep to the Tenon fascia and appearing as a translucent firm elevation was seen in all 4 cases. Axial CT (case 1) revealed a circumscribed anterior temporal orbital mass, believed to be a large inclusion cyst, 4 times thicker than the nasal scleral buckle. Ocular ultrasonography depicted an echolucent mass in the episcleral region (cases 3 and 4) that was 2 times thicker than the nasal scleral buckle (case 3). Excision was attempted in case 1, but only piecemeal removal was achieved, leading to extensive postoperative inflammation and decreased vision. The other 3 cases were followed conservatively without excision because they were each recognized to be a swollen MIRAgel implant and not an orbital tumor. MIRAgel scleral buckle material can greatly enlarge over a period of 10 years and simulate an orbital tumor or orbital cyst. Patients often do not recall details of the retinal surgery. Caution is advised regarding excision of this material because it is friable and can lead to extensive postoperative inflammation.

The effect of misclassification errors on case mix measurement.

PubMed

Sutherland, Jason M; Botz, Chas K

2006-12-01

Case mix systems have been implemented for hospital reimbursement and performance measurement across Europe and North America. Case mix categorizes patients into discrete groups based on clinical information obtained from patient charts in an attempt to identify clinical or cost difference amongst these groups. The diagnosis related group (DRG) case mix system is the most common methodology, with variants adopted in many countries. External validation studies of coding quality have confirmed that widespread variability exists between originally recorded diagnoses and re-abstracted clinical information. DRG assignment errors in hospitals that share patient level cost data for the purpose of establishing cost weights affects cost weight accuracy. The purpose of this study is to estimate bias in cost weights due to measurement error of reported clinical information. DRG assignment error rates are simulated based on recent clinical re-abstraction study results. Our simulation study estimates that 47% of cost weights representing the least severe cases are over weight by 10%, while 32% of cost weights representing the most severe cases are under weight by 10%. Applying the simulated weights to a cross-section of hospitals, we find that teaching hospitals tend to be under weight. Since inaccurate cost weights challenges the ability of case mix systems to accurately reflect patient mix and may lead to potential distortions in hospital funding, bias in hospital case mix measurement highlights the role clinical data quality plays in hospital funding in countries that use DRG-type case mix systems. Quality of clinical information should be carefully considered from hospitals that contribute financial data for establishing cost weights.

Teaching cardiopulmonary auscultation in workshops using a virtual patient simulation technology - A pilot study.

PubMed

Pereira, D; Gomes, P; Faria, S; Cruz-Correia, R; Coimbra, M

2016-08-01

Auscultation is currently both a powerful screening tool, providing a cheap and quick initial assessment of a patient's clinical condition, and a hard skill to master. The teaching of auscultation in Universities is today reduced to an unsuitable number of hours. Virtual patient simulators can potentially mitigate this problem, by providing an interesting high-quality alternative to teaching with real patients or patient simulators. In this paper we evaluate the pedagogical impact of using a virtual patient simulation technology in a short workshop format for medical students, training them to detect cardiac pathologies. Results showed a significant improvement (+16%) in the differentiation between normal and pathological cases, although longer duration formats seem to be needed to accurately identify specific pathologies.

Specificity and sensitivity of objective tests to detect possible malingering in fibromyalgia: a case-control study in 211 Spanish patients.

PubMed

Belenguer-Prieto, Rafael; Morales-Espinoza, Emma M; Martín-González, Rosa M; Brito-Zerón, Pilar; Pastor-Oliver, Jose F; Kostov, Belchin; Buss, David; Gómez-Gálvez, Cayetano; Salazar-Cifre, Antonio; Sisó-Almirall, Antoni; Ramos-Casals, Manuel

2013-01-01

To characterise patients diagnosed with fibromyalgia (FM) who present a clinical profile suggestive of simulation. Observational case-control study of 218 patients who met the classification criteria for FM. The profile supporting simulation was based on the proposed criteria for evaluating disability related to the simulation of pain. Compared with controls (n=105), patients with suspected simulation of FM (n=106) had a higher mean age (52.5 vs. 49.2 years, p=0.003), a higher frequency of primary education (88.7% vs. 58.1%; p<0.001), a higher percentage of separated/widowed persons (33.9% vs. 8.6%, p<0.001), a higher frequency of psychiatric disorders (100% vs. 67.6%, p<0.001), a higher mean number of positive 'control' tender points (4.5 vs. 1.3, p<0.001), a higher mean FIQ questionnaire score (89.8 vs. 68.8, p<0.001) and a lower mean LHS questionnaire score (41.0 vs. 59.9, p<0.001). Patients with suspected simulation were able to walk a shorter distance in the 6-minute walk test than controls (231.0 vs. 356.3 metres, p<0.001), while the appearance of allodynia was achieved with a significantly lower mmHg pressure (159.8 vs. 229.9 mm Hg, p<0.001). Some physical/functional tests, together with the administration of specific questionnaires, may identify a subgroup of patients with FM with a profile consistent with simulation or malingering; these patients have a differentiated demographic and psychiatric profile in comparison with FM patients without a profile of simulation.

Building the evidence on simulation validity: comparison of anesthesiologists' communication patterns in real and simulated cases.

PubMed

Weller, Jennifer; Henderson, Robert; Webster, Craig S; Shulruf, Boaz; Torrie, Jane; Davies, Elaine; Henderson, Kaylene; Frampton, Chris; Merry, Alan F

2014-01-01

Effective teamwork is important for patient safety, and verbal communication underpins many dimensions of teamwork. The validity of the simulated environment would be supported if it elicited similar verbal communications to the real setting. The authors hypothesized that anesthesiologists would exhibit similar verbal communication patterns in routine operating room (OR) cases and routine simulated cases. The authors further hypothesized that anesthesiologists would exhibit different communication patterns in routine cases (real or simulated) and simulated cases involving a crisis. Key communications relevant to teamwork were coded from video recordings of anesthesiologists in the OR, routine simulation and crisis simulation and percentages were compared. The authors recorded comparable videos of 20 anesthesiologists in the two simulations, and 17 of these anesthesiologists in the OR, generating 400 coded events in the OR, 683 in the routine simulation, and 1,419 in the crisis simulation. The authors found no significant differences in communication patterns in the OR and the routine simulations. The authors did find significant differences in communication patterns between the crisis simulation and both the OR and the routine simulations. Participants rated team communication as realistic and considered their communications occurred with a similar frequency in the simulations as in comparable cases in the OR. The similarity of teamwork-related communications elicited from anesthesiologists in simulated cases and the real setting lends support for the ecological validity of the simulation environment and its value in teamwork training. Different communication patterns and frequencies under the challenge of a crisis support the use of simulation to assess crisis management skills.

Evaluation of a Computer Simulation in a Therapeutics Case Discussion.

ERIC Educational Resources Information Center

Kinkade, Raenel E.; And Others

1995-01-01

A computer program was used to simulate a case presentation in pharmacotherapeutics. Students (n=24) used their knowledge of the disease (glaucoma) and various topical agents on the computer program's formulary to "treat" the patient. Comparison of results with a control group found the method as effective as traditional case…

Simulation in Nursing Education-International Perspectives and Contemporary Scope of Practice.

PubMed

Kelly, Michelle A; Berragan, Elizabeth; Husebø, Sissel Eikeland; Orr, Fiona

2016-05-01

This article provides insights and perspectives from four experienced educators about their approaches to developing, delivering, and evaluating impactful simulation learning experiences for undergraduate nurses. A case study format has been used to illustrate the commonalities and differences of where simulation has been positioned within curricula, with examples of specialized clinical domains and others with a more generic focus. The importance of pedagogy in developing and delivering simulations is highlighted in each case study. A range of learning theories appropriate for healthcare simulations are a reminder of the commonalities across theories and that no one theory can account for the engaging and impactful learning that simulation elicits. Creating meaningful and robust learning experiences through simulation can benefit students' performance in subsequent clinical practice. The ability to rehearse particular clinical scenarios, which may be difficult to otherwise achieve, assists students in anticipating likely patient trajectories and understanding how to respond to patients, relatives, and others in the healthcare team. © 2016 Sigma Theta Tau International.

Simulation of Ventricular, Cavo-Pulmonary, and Biventricular Ventricular Assist Devices in Failing Fontan.

PubMed

Di Molfetta, Arianna; Amodeo, Antonio; Fresiello, Libera; Trivella, Maria Giovanna; Iacobelli, Roberta; Pilati, Mara; Ferrari, Gianfranco

2015-07-01

Considering the lack of donors, ventricular assist devices (VADs) could be an alternative to heart transplantation for failing Fontan patients, in spite of the lack of experience and the complex anatomy and physiopathology of these patients. Considering the high number of variables that play an important role such as type of Fontan failure, type of VAD connection, and setting (right VAD [RVAD], left VAD [LVAD], or biventricular VAD [BIVAD]), a numerical model could be useful to support clinical decisions. The aim of this article is to develop and test a lumped parameter model of the cardiovascular system simulating and comparing the VAD effects on failing Fontan. Hemodynamic and echocardiographic data of 10 Fontan patients were used to simulate the baseline patients' condition using a dedicated lumped parameter model. Starting from the simulated baseline and for each patient, a systolic dysfunction, a diastolic dysfunction, and an increment of the pulmonary vascular resistance were simulated. Then, for each patient and for each pathology, the RVAD, LVAD, and BIVAD implantations were simulated. The model can reproduce patients' baseline well. In the case of systolic dysfunction, the LVAD unloads the single ventricle and increases the cardiac output (CO) (35%) and the arterial systemic pressure (Pas) (25%). With RVAD, a decrement of inferior vena cava pressure (Pvci) (39%) was observed with 34% increment of CO, but an increment of the single ventricle external work (SVEW). With the BIVAD, an increment of Pas (29%) and CO (37%) was observed. In the case of diastolic dysfunction, the LVAD increases CO (42%) and the RVAD decreases the Pvci, while both increase the SVEW. In the case of pulmonary vascular resistance increment, the highest CO (50%) and Pas (28%) increment is obtained with an RVAD with the highest decrement of Pvci (53%) and an increment of the SVEW but with the lowest VAD power consumption. The use of numerical models could be helpful in this innovative field to evaluate the effect of VAD implantation on Fontan patients to support patient and VAD type selection personalizing the assistance. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Instructional Simulation Integrates Research, Education, and Practice.

PubMed

Teasdale, Thomas A; Mapes, Sheryl A; Henley, Omolara; Lindsey, Jeanene; Dillard, Della

2016-01-01

Instructional simulation is widely used in clinical education. Examples include the use of inanimate models meant to imitate humans, standardized patients who are actors portraying patients with certain conditions, and role-play where learners experience the disease through props and circumstances. These modalities are briefly described, and then case examples are provided of simulation curricula in use that integrate research findings and clinical practice expertise to guide development and implementation steps. The cases illustrate how formative and summative feedback from two legs of the "three-legged stool" can be potent integrating forces in development of simulation curricula. In these examples, the educational outputs benefit from purposeful inclusion of research and practice inputs. Costs are outlined for instructor and learner time commitments, space considerations, and expendables. The authors' data and experience suggest that instructional simulation that is supported by a solid scientific base and clinical expertise is appreciated by teachers and learners.

SU-F-R-39: Effects of Radiation Dose Reduction On Renal Cell Carcinoma Discrimination Using Multi-Phasic CT Imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wahi-Anwar, M; Young, S; Lo, P

Purpose: A method to discriminate different types of renal cell carcinoma (RCC) was developed using attenuation values observed in multiphasic contrast-enhanced CT. This work evaluates the sensitivity of this RCC discrimination task at different CT radiation dose levels. Methods: We selected 5 cases of kidney lesion patients who had undergone four-phase CT scans covering the abdomen to the lilac crest. Through an IRB-approved study, the scans were conducted on 64-slice CT scanners (Definition AS/Definition Flash, Siemens Healthcare) using automatic tube-current modulation (TCM). The protocol included an initial baseline unenhanced scan, followed by three post-contrast injection phases. CTDIvol (32 cm phantom)more » measured between 9 to 35 mGy for any given phase. As a preliminary study, we limited the scope to the cortico-medullary phase—shown previously to be the most discriminative phase. A previously validated method was used to simulate a reduced dose acquisition via adding noise to raw CT sinogram data, emulating corresponding images at simulated doses of 50%, 25%, and 10%. To discriminate the lesion subtype, ROIs were placed in the most enhancing region of the lesion. The mean HU value of an ROI was extracted and used to discriminate to the worst-case RCC subtype, ranked in the order of clear cell, papillary, chromophobe and the benign oncocytoma. Results: Two patients exhibited a change of worst case RCC subtype between original and simulated scans, at 25% and 10% doses. In one case, the worst-case RCC subtype changed from oncocytoma to chromophobe at 10% and 25% doses, while the other case changed from oncocytoma to clear cell at 10% dose. Conclusion: Based on preliminary results from an initial cohort of 5 patients, worst-case RCC subtypes remained constant at all simulated dose levels except for 2 patients. Further study conducted on more patients will be needed to confirm our findings. Institutional research agreement, Siemens Healthcare; Past recipient, research grant support, Siemens Healthcare; Consultant, Toshiba America Medical Systems; Consultant, Samsung Electronics; NIH Grant Support from: U01 CA181156.« less

Granuloma Inguinale Simulating Squamous Cell Carcinoma.

PubMed

Mani, M Z; Singh, Trilochan; Mathew, Mary

1981-01-01

A case of extensive granuloma inguinale simulating squamous cell carcinoma is described. There was past history of urethritis leading to a urethral fistula. The ulcer healed almost completely within 19 days of receiving streptomycin injections. The patient had associated scabies and presumably also had latent syphillis (His VDRL was reactive in 1:8 dilution). The patient belonged to Madhya Pradesh.

Use of patient specific 3D printed neurovascular phantoms to evaluate the clinical utility of a high resolution x-ray imager

NASA Astrophysics Data System (ADS)

Setlur Nagesh, S. V.; Russ, M.; Ionita, C. N.; Bednarek, D.; Rudin, S.

2017-03-01

Modern 3D printing technology can fabricate vascular phantoms based on an actual human patient with a high degree of precision facilitating a realistic simulation environment for an intervention. We present two experimental setups using 3D printed patient-specific neurovasculature to simulate different disease anatomies. To simulate the human neurovasculature in the Circle of Willis, patient-based phantoms with aneurysms were 3D printed using a Objet Eden 260V printer. Anthropomorphic head phantoms and a human skull combined with acrylic plates simulated human head bone anatomy and x-ray attenuation. For dynamic studies the 3D printed phantom was connected to a pulsatile flow loop with the anthropomorphic phantom underneath. By combining different 3D printed phantoms and the anthropomorphic phantoms, different patient pathologies can be simulated. For static studies a 3D printed neurovascular phantom was embedded inside a human skull and used as a positional reference for treatment devices such as stents. To simulate tissue attenuation acrylic layers were added. Different combinations can simulate different patient treatment procedures. The Complementary-Metal-Oxide-Semiconductor (CMOS) based High Resolution Fluoroscope (HRF) with 75μm pixels offers an advantage over the state-of-the-art 200 μm pixel Flat Panel Detector (FPD) due to higher Nyquist frequency and better DQE performance. Whether this advantage is clinically useful during an actual clinical neurovascular intervention can be addressed by qualitatively evaluating images from a cohort of various cases performed using both detectors. The above-mentioned method can offer a realistic substitute for an actual clinical procedure. Also a large cohort of cases can be generated and used for a HRF clinical utility determination study.

Multicenter, randomized, controlled trial of virtual-reality simulator training in acquisition of competency in colonoscopy.

PubMed

Cohen, Jonathan; Cohen, Seth A; Vora, Kinjal C; Xue, Xiaonan; Burdick, J Steven; Bank, Simmy; Bini, Edmund J; Bodenheimer, Henry; Cerulli, Maurice; Gerdes, Hans; Greenwald, David; Gress, Frank; Grosman, Irwin; Hawes, Robert; Mullin, Gerard; Mullen, Gerard; Schnoll-Sussman, Felice; Starpoli, Anthony; Stevens, Peter; Tenner, Scott; Villanueva, Gerald

2006-09-01

The GI Mentor is a virtual reality simulator that uses force feedback technology to create a realistic training experience. To define the benefit of training on the GI Mentor on competency acquisition in colonoscopy. Randomized, controlled, blinded, multicenter trial. Academic medical centers with accredited gastroenterology training programs. First-year GI fellows. Subjects were randomized to receive 10 hours of unsupervised training on the GI Mentor or no simulator experience during the first 8 weeks of fellowship. After this period, both groups began performing real colonoscopies. The first 200 colonoscopies performed by each fellow were graded by proctors to measure technical and cognitive success, and patient comfort level during the procedure. A mixed-effects model comparison between the 2 groups of objective and subjective competency scores and patient discomfort in the performance of real colonoscopies over time. Forty-five fellows were randomized from 16 hospitals over 2 years. Fellows in the simulator group had significantly higher objective competency rates during the first 100 cases. A mixed-effects model demonstrated a higher objective competence overall in the simulator group (P < .0001), with the difference between groups being significantly greater during the first 80 cases performed. The median number of cases needed to reach 90% competency was 160 in both groups. The patient comfort level was similar. Fellows who underwent GI Mentor training performed significantly better during the early phase of real colonoscopy training.

Nursing students' perceptions of high- and low-fidelity simulation used as learning methods.

PubMed

Tosterud, Randi; Hedelin, Birgitta; Hall-Lord, Marie Louise

2013-07-01

Due to the increasing focus on simulation used in nursing education, there is a need to examine how the scenarios and different simulation methods used are perceived by students. The aim of this study was to examine nursing students' perceptions of scenarios played out in different simulation methods, and whether their educational level influenced their perception. The study had a quantitative, evaluative and comparative design. The sample consisted of baccalaureate nursing students (n = 86) within various educational levels. The students were randomly divided into groups. They solved a patient case adapted to their educational level by using a high-fidelity patient simulator, a static mannequin or a paper/pencil case study. Data were collected by three instruments developed by the National League for Nursing. The results showed that the nursing students reported satisfaction with the implementation of the scenarios regardless of the simulation methods used. The findings indicated that the students who used the paper/pencil case study were the most satisfied. Moreover, educational level did not seem to influence their perceptions. Independent of educational level, the findings indicated that simulation with various degrees of fidelity could be used in nursing education. There is a need for further research to examine more closely the rationale behind the students' perception of the simulation methods. Copyright © 2013 Elsevier Ltd. All rights reserved.

Planning acetabular fracture reduction using patient-specific multibody simulation of the hip

NASA Astrophysics Data System (ADS)

Oliveri, Hadrien; Boudissa, Mehdi; Tonetti, Jerome; Chabanas, Matthieu

2017-03-01

Acetabular fractures are a challenge in orthopedic surgery. Computer-aided solutions were proposed to segment bone fragments, simulate the fracture reduction or design the osteosynthesis fixation plates. This paper addresses the simulation part, which is usually carried out by freely moving bone fragments with six degrees of freedom to reproduce the pre-fracture state. Instead we propose a different paradigm, closer to actual surgeon's requirements: to simulate the surgical procedure itself rather than the desired result. A simple, patient-specific, biomechanical multibody model is proposed, integrating the main ligaments and muscles of the hip joint while accounting for contacts between bone fragments. Main surgical tools and actions can be simulated, such as clamps, Schanz screws or traction of the femur. Simulations are computed interactively, which enables clinicians to evaluate different strategies for an optimal surgical planning. Six retrospective cases were studied, with simple and complex fracture patterns. After interactively building the models from preoperative CT, gestures from the surgical reports were reproduced. Results of the simulations could then be compared with postoperative CT data. A qualitative study shows the model behavior is excellent and the simulated reductions fit the observed data. A more quantitative analysis is currently being completed. Two cases are particularly significant, for which the surgical reduction actually failed. Simulations show it was indeed not possible to reduce these fractures with the chosen approach. Had our simulator being used, a better planning may have avoided a second surgery to these patients.

Lung assist devices influence cardio-energetic parameters: Numerical simulation study.

PubMed

De Lazzari, C; Quatember, B; Recheis, W; Mayr, M; Demertzis, S; Allasia, G; De Rossi, A; Cavoretto, R; Venturino, E; Genuini, I

2015-08-01

We aim at an analysis of the effects mechanical ventilators (MVs) and thoracic artificial lungs (TALs) will have on the cardiovascular system, especially on important quantities, such as left and right ventricular external work (EW), pressure-volume area (PVA) and cardiac mechanical efficiency (CME). Our analyses are based on simulation studies which were carried out by using our CARDIOSIM(©) software simulator. At first, we carried out simulation studies of patients undergoing mechanical ventilation (MV) without a thoracic artificial lung (TAL). Subsequently, we conducted simulation studies of patients who had been provided with a TAL, but did not undergo MV. We aimed at describing the patient's physiological characteristics and their variations with time, such as EW, PVA, CME, cardiac output (CO) and mean pulmonary arterial/venous pressure (PAP/PVP). We were starting with a simulation run under well-defined initial conditions which was followed by simulation runs for a wide range of mean intrathoracic pressure settings. Our simulations of MV without TAL showed that for mean intrathoracic pressure settings from negative (-4 mmHg) to positive (+5 mmHg) values, the left and right ventricular EW and PVA, right ventricular CME and CO decreased, whereas left ventricular CME and the PAP increased. The simulation studies of patients with a TAL, comprised all the usual TAL arrangements, viz. configurations "in series" and in parallel with the natural lung and, moreover, hybrid configurations. The main objective of the simulation studies was, as before, the assessment of the hemodynamic response to the application of a TAL. We could for instance show that, in case of an "in series" configuration, a reduction (an increase) in left (right) ventricular EW and PVA values occurred, whereas the best performance in terms of CO can be achieved in the case of an in parallel configuration.

Modeling the impact of changing patient transportation systems on peri-operative process performance in a large hospital: insights from a computer simulation study.

PubMed

Segev, Danny; Levi, Retsef; Dunn, Peter F; Sandberg, Warren S

2012-06-01

Transportation of patients is a key hospital operational activity. During a large construction project, our patient admission and prep area will relocate from immediately adjacent to the operating room suite to another floor of a different building. Transportation will require extra distance and elevator trips to deliver patients and recycle transporters (specifically: personnel who transport patients). Management intuition suggested that starting all 52 first cases simultaneously would require many of the 18 available elevators. To test this, we developed a data-driven simulation tool to allow decision makers to simultaneously address planning and evaluation questions about patient transportation. We coded a stochastic simulation tool for a generalized model treating all factors contributing to the process as JAVA objects. The model includes elevator steps, explicitly accounting for transporter speed and distance to be covered. We used the model for sensitivity analyses of the number of dedicated elevators, dedicated transporters, transporter speed and the planned process start time on lateness of OR starts and the number of cases with serious delays (i.e., more than 15 min). Allocating two of the 18 elevators and 7 transporters reduced lateness and the number of cases with serious delays. Additional elevators and/or transporters yielded little additional benefit. If the admission process produced ready-for-transport patients 20 min earlier, almost all delays would be eliminated. Modeling results contradicted clinical managers' intuition that starting all first cases on time requires many dedicated elevators. This is explained by the principle of decreasing marginal returns for increasing capacity when there are other limiting constraints in the system.

Computer-Assisted Orthognathic Surgery for Patients with Cleft Lip/Palate: From Traditional Planning to Three-Dimensional Surgical Simulation

PubMed Central

Lonic, Daniel; Pai, Betty Chien-Jung; Yamaguchi, Kazuaki; Chortrakarnkij, Peerasak; Lin, Hsiu-Hsia; Lo, Lun-Jou

2016-01-01

Background Although conventional two-dimensional (2D) methods for orthognathic surgery planning are still popular, the use of three-dimensional (3D) simulation is steadily increasing. In facial asymmetry cases such as in cleft lip/palate patients, the additional information can dramatically improve planning accuracy and outcome. The purpose of this study is to investigate which parameters are changed most frequently in transferring a traditional 2D plan to 3D simulation, and what planning parameters can be better adjusted by this method. Patients and Methods This prospective study enrolled 30 consecutive patients with cleft lip and/or cleft palate (mean age 18.6±2.9 years, range 15 to 32 years). All patients received two-jaw single-splint orthognathic surgery. 2D orthodontic surgery plans were transferred into a 3D setting. Severe bony collisions in the ramus area after 2D plan transfer were noted. The position of the maxillo-mandibular complex was evaluated and eventually adjusted. Position changes of roll, midline, pitch, yaw, genioplasty and their frequency within the patient group were recorded as an alternation of the initial 2D plan. Patients were divided in groups of no change from the original 2D plan and changes in one, two, three and four of the aforementioned parameters as well as subgroups of unilateral, bilateral cleft lip/palate and isolated cleft palate cases. Postoperative OQLQ scores were obtained for 20 patients who finished orthodontic treatment. Results 83.3% of 2D plans were modified, mostly concerning yaw (63.3%) and midline (36.7%) adjustments. Yaw adjustments had the highest mean values in total and in all subgroups. Severe bony collisions as a result of 2D planning were seen in 46.7% of patients. Possible asymmetry was regularly foreseen and corrected in the 3D simulation. Conclusion Based on our findings, 3D simulation renders important information for accurate planning in complex cleft lip/palate cases involving facial asymmetry that is regularly missed in conventional 2D planning. PMID:27002726

Non-prescription treatment of NSAID induced GORD by Australian pharmacies: a national simulated patient study.

PubMed

MacFarlane, Brett; Matthews, Andrew; Bergin, Jenny

2015-10-01

Patients regularly present to community pharmacies for advice about and treatment for reflux symptoms and NSAIDs are a common cause of these symptoms. There is no published literature detailing the approach that pharmacies take to these enquiries, the pharmacotherapy they recommend or whether they contribute to the safe and effective use of reflux medicines. To assess in an observational study design the clinical history gathering, recommendations for GORD management and counselling provided by community pharmacies in a simulated patient scenario involving suspected NSAID induced reflux symptoms. Setting Australian community pharmacies. Simulated patients visited 223 community pharmacies to request treatment for reflux symptoms. The interaction was audiotaped and assessed against guidelines for the treatment of reflux symptoms. Alignment of community pharmacies with international expert gastroenterologist guidance and national professional practice guidelines for the treatment of reflux symptoms by pharmacists including: consultation with a pharmacist; confirmation of reflux diagnosis based on symptoms; recommendation of short courses proton pump inhibitor (PPI) therapy; advice on the safe and effective use of reflux medicines and referral to a doctor for further assessment. Pharmacists consulted with the simulated patient in 77% of cases. Symptoms were enquired about in 95% of cases and a medicines history taken in 69% of cases. Recommendations for treatment included: PPIs (18%), histamine H2 antagonists (57%) and antacids (19%). Advice on product use was given in 83% of cases. Referral to a doctor to discuss reflux symptoms was made in 63% of cases. When assessing patients for the symptoms of GORD, Australian pharmacists and non-pharmacist support staff take a comprehensive history including symptomatology, duration of symptoms, concomitant medicines and medical conditions and any GORD treatments previously trialled. They provide comprehensive counselling on the use of antisecretory and antacid medicines. Counselling could involve more comprehensive information on lifestyle approaches for GORD management and side effects of antisecretory and antacid medicines. Further alignment with guidelines for the management of GORD would result in greater referral to a doctor for assessment of recurrent GORD and greater recommendation of PPIs for symptoms. However alignment with guidelines by all pharmacists is unrealistic if the guidelines are not universally available to them.

MO-E-BRB-00: PANEL DISCUSSION: SBRT/SRS Case Studies - Lung

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

2016-06-15

In this interactive session, lung SBRT patient cases will be presented to highlight real-world considerations for ensuring safe and accurate treatment delivery. An expert panel of speakers will discuss challenges specific to lung SBRT including patient selection, patient immobilization techniques, 4D CT simulation and respiratory motion management, target delineation for treatment planning, online treatment alignment, and established prescription regimens and OAR dose limits. Practical examples of cases, including the patient flow thought the clinical process are presented and audience participation will be encouraged. This panel session is designed to provide case demonstration and review for lung SBRT in terms ofmore » (1) clinical appropriateness in patient selection, (2) strategies for simulation, including 4D and respiratory motion management, and (3) applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent, and (4) image guidance in treatment delivery. Learning Objectives: Understand the established requirements for patient selection in lung SBRT Become familiar with the various immobilization strategies for lung SBRT, including technology for respiratory motion management Understand the benefits and pitfalls of applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent determination for lung SBRT Understand established prescription regimes and OAR dose limits.« less

Case-mix reimbursement for nursing home services: Simulation approach

PubMed Central

Adams, E. Kathleen; Schlenker, Robert E.

1986-01-01

Nursing home reimbursement based on case mix is a matter of growing interest. Several States either use or are considering this reimbursement method. In this article, we present a method for evaluating key outcomes of such a change for Connecticut nursing homes. A simulation model is used to replicate payments under the case-mix systems used in Maryland, Ohio, and West Virginia. The findings indicate that, compared with the system presently used in Connecticut, these systems would better relate dollar payments to measure patient need, and for-profit homes would benefit relative to nonprofit homes. The Ohio methodology would impose the most additional costs, the West Virginia system would actually be somewhat less expensive in terms of direct patient care payments. PMID:10311776

Case-mix reimbursement for nursing home services: simulation approach.

PubMed

Adams, E K; Schlenker, R E

1986-01-01

Nursing home reimbursement based on case mix is a matter of growing interest. Several States either use or are considering this reimbursement method. In this article, we present a method for evaluating key outcomes of such a change for Connecticut nursing homes. A simulation model is used to replicate payments under the case-mix systems used in Maryland, Ohio, and West Virginia. The findings indicate that, compared with the system presently used in Connecticut, these systems would better relate dollar payments to measure patient need, and for-profit homes would benefit relative to nonprofit homes. The Ohio methodology would impose the most additional costs, the West Virginia system would actually be somewhat less expensive in terms of direct patient care payments.

Scaffolding Interprofessional Education: Unfolding Case Studies, Virtual World Simulations, and Patient-Centered Care.

PubMed

Zook, Sharon Strang; Hulton, Linda J; Dudding, Carol C; Stewart, Anne L; Graham, Amy C

Fragmentation of health care negatively impacts quality; one of the contributing factors may be ineffective collaboration among health care professionals. This article describes the implementation of an interprofessional education curriculum for graduate students enrolled in nursing, psychology, and speech-language pathology programs. Over 3 semesters, students engaged in interprofessional collaboration modules, unfolding case studies, virtual simulation, and shared case planning experiences. The curriculum's impact on students' attitudes and values toward interprofessional collaborative practice was measured.

[Auricular sporotrichosis. Atypical case report simulating bacterial cellulitis].

PubMed

Ochoa-Reyes, Juan; Ramos-Martínez, Ernesto; Treviño-Rangel, Rogelio; González, Gloria M; Bonifaz, Alexandro

Sporotrichosis is the most common subcutaneous or implantation mycosis in Mexico. The case of a preauricular cutaneous-fixed sporotrichosis simulating atypical bacterial cellulitis is reported in an elderly patient with no history of trauma. The biopsy showed a suppurative granuloma with scarce yeast. Sporothrix schenckii was identified in the culture and confirmed by molecular biology. She was treated with itraconazole and a clinical and mycological cure was obtained. The case of atypical presentation is presented, coming from a semi-arid zone with extreme weather.

The skill of summary in clinician-patient communication: a case study.

PubMed

Quilligan, Sally; Silverman, Jonathan

2012-03-01

To investigate the use and impact of the micro-skill of summary in clinical encounters, a core skill that has little empirical investigation of its use and outcomes. This exploratory study used a mixed method design. Video recordings of ten consultations between simulated patients and medical-students were analysed to identify types of summary used. Two contrasting cases were then micro-analysed and follow up interviews held with the 2 students and simulated patients, involved in the consultations, using the video recording as a trigger. Ninety-nine summaries were identified and grouped into six types: reflective, screening, clarifying, paraphrasing, interim and full. Summary appeared to aid accuracy. However, summaries about the patient's perspective were summarised less frequently than the biomedical perspective. When summaries were repeatedly incorrect they made the simulated patient feel they were not being listened to. The use and effect of summary appears more complex than the medical literature suggests and may have both positive and negative attributes. Further research is needed to investigate whether these preliminary findings are replicated within doctor-patient consultations. When teaching use of summary we need to address: type, purpose, accuracy, effect on patient and flexible use to suit the patient. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

[Relevance of a driving simulator in the assessment of handicapped individuals].

PubMed

Carroz, A; Comte, P-A; Nicolo, D; Dériaz, O; Vuadens, P

2008-06-01

To evaluate the value of our driving simulator in deciding whether or not to allow patients with physical and/or cognitive deficits to resuming driving and to analyze whether or not the medical expert's final decision is based more on the results of the driving simulator than those of the neuropsychological examination. One hundred and twenty-three patients were evaluated with the driving simulator. Thirty-five of those with cognitive deficits also underwent a neuropsychological examination prior to the medical expert's decision on driving aptitude. In cases of uncertainty or disagreement, a driving assessment in real conditions was performed by a driving instructor. In cases of physical handicap, the medical expert's decision concurred with that of the occupational therapist. For brain-injured patients, there was a significant correlation between the neuropsychologist's opinion and that of the occupational therapist (kappa=0.33; P=0.01). However, the sensibility and specificity were only 55 and 80%, respectively. The correlation between an occupational therapy decision based on the driving simulator and that of the medical expert was very significant (kappa=0.81; P<0.0001) and the sensibility and specificity were 84 and 100%, respectively. In contrast, these values were lower (63 and 71%, respectively) for the correlation between the neuropsychologist's opinion and that of the medical expert. Our driving simulator enables the danger-free evaluation of driving aptitude. The results mirror an in situ assessment and are more sensitive than neuropsychological examination. In fact, the neuropsychologist's opinion often is more negative or uncertain with respect to the patient's real driving aptitude. When taking a decision on a patient's driving aptitude, the medical expert is more inclined to trust the results of the driving simulator.

Simulation Pedagogy With Nurse Practitioner Students: Impact of Receiving Immediate Individualized Faculty Feedback.

PubMed

Grossman, Sheila; Conelius, Jaclyn

2015-01-01

Family nurse practitioner (FNP) students must achieve basic competency in managing patients' primary care needs across the lifespan. Students in the FNP program have simulations integrated throughout their clinical theory courses to increase practice time with various patient cases. Students who received individualized faculty feedback immediately after self-evaluation of simulation performance showed statistically significantly increased knowledge (as evidenced by higher grades in course examinations and preceptor evaluations) than a control group of students who received feedback in a group class via a rubric grading guide 2-4 weeks after all students completed their individual simulations.

[System-immanent incentives in the remuneration for psychiatry and psychosomatics : Analysis exemplified by treatment of alcohol-related disorders].

PubMed

Horter, H; Zapp, W; Driessen, M

2016-07-01

The German fixed rate remuneration system in psychiatry and psychosomatics (PEPP) has been criticized by many specialty associations because negative effects on mental healthcare are expected through economic incentives. Through analysis of performance data in the treatment of alcohol dependency at the Evangelical Hospital Bielefeld (Evangelisches Krankenhaus Bielefeld, EvKB) from 2014 and various simulations, the incentives of the PEPP (version 2015) were analyzed and its potential impact on patient care was evaluated. Groups of cases were created based on the clinical data. Various parameters were evaluated, such as duration of treatment, PEPP coding, loss of income by merging cases and case remuneration. Additionally, changes in the duration of treatment, the intensity of treatment and the intensity of care were simulated. In the simulations a reduction in the duration of treatment by 16.1 % led to additional revenues of 1.9 % per treatment day. The calculated additional costs of 1:1 care and intensive nursing care were not completely covered by the additional revenues, whereas psychotherapeutic inpatient treatment programs showed positive profit contributions. Complicated cases with increased merging of cases showed lower revenues but with above average expenditure of efforts. The current version of the PEPP leads to misdirected incentives in patient care. This is caused, for example, by the fact that higher profit contributions can be realized in some patient groups and intensive nursing care of patients is insufficiently represented. It is not clear whether these incentives will persist or can be compensated in subsequent versions of the system.

Computer-Assisted Orthognathic Surgery for Patients with Cleft Lip/Palate: From Traditional Planning to Three-Dimensional Surgical Simulation.

PubMed

Lonic, Daniel; Pai, Betty Chien-Jung; Yamaguchi, Kazuaki; Chortrakarnkij, Peerasak; Lin, Hsiu-Hsia; Lo, Lun-Jou

2016-01-01

Although conventional two-dimensional (2D) methods for orthognathic surgery planning are still popular, the use of three-dimensional (3D) simulation is steadily increasing. In facial asymmetry cases such as in cleft lip/palate patients, the additional information can dramatically improve planning accuracy and outcome. The purpose of this study is to investigate which parameters are changed most frequently in transferring a traditional 2D plan to 3D simulation, and what planning parameters can be better adjusted by this method. This prospective study enrolled 30 consecutive patients with cleft lip and/or cleft palate (mean age 18.6±2.9 years, range 15 to 32 years). All patients received two-jaw single-splint orthognathic surgery. 2D orthodontic surgery plans were transferred into a 3D setting. Severe bony collisions in the ramus area after 2D plan transfer were noted. The position of the maxillo-mandibular complex was evaluated and eventually adjusted. Position changes of roll, midline, pitch, yaw, genioplasty and their frequency within the patient group were recorded as an alternation of the initial 2D plan. Patients were divided in groups of no change from the original 2D plan and changes in one, two, three and four of the aforementioned parameters as well as subgroups of unilateral, bilateral cleft lip/palate and isolated cleft palate cases. Postoperative OQLQ scores were obtained for 20 patients who finished orthodontic treatment. 83.3% of 2D plans were modified, mostly concerning yaw (63.3%) and midline (36.7%) adjustments. Yaw adjustments had the highest mean values in total and in all subgroups. Severe bony collisions as a result of 2D planning were seen in 46.7% of patients. Possible asymmetry was regularly foreseen and corrected in the 3D simulation. Based on our findings, 3D simulation renders important information for accurate planning in complex cleft lip/palate cases involving facial asymmetry that is regularly missed in conventional 2D planning.

A model to create an efficient and equitable admission policy for patients arriving to the cardiothoracic ICU.

PubMed

Yang, Muer; Fry, Michael J; Raikhelkar, Jayashree; Chin, Cynthia; Anyanwu, Anelechi; Brand, Jordan; Scurlock, Corey

2013-02-01

To develop queuing and simulation-based models to understand the relationship between ICU bed availability and operating room schedule to maximize the use of critical care resources and minimize case cancellation while providing equity to patients and surgeons. Retrospective analysis of 6-month unit admission data from a cohort of cardiothoracic surgical patients, to create queuing and simulation-based models of ICU bed flow. Three different admission policies (current admission policy, shortest-processing-time policy, and a dynamic policy) were then analyzed using simulation models, representing 10 yr worth of potential admissions. Important output data consisted of the "average waiting time," a proxy for unit efficiency, and the "maximum waiting time," a surrogate for patient equity. A cardiothoracic surgical ICU in a tertiary center in New York, NY. Six hundred thirty consecutive cardiothoracic surgical patients admitted to the cardiothoracic surgical ICU. None. Although the shortest-processing-time admission policy performs best in terms of unit efficiency (0.4612 days), it did so at expense of patient equity prolonging surgical waiting time by as much as 21 days. The current policy gives the greatest equity but causes inefficiency in unit bed-flow (0.5033 days). The dynamic policy performs at a level (0.4997 days) 8.3% below that of the shortest-processing-time in average waiting time; however, it balances this with greater patient equity (maximum waiting time could be shortened by 4 days compared to the current policy). Queuing theory and computer simulation can be used to model case flow through a cardiothoracic operating room and ICU. A dynamic admission policy that looks at current waiting time and expected ICU length of stay allows for increased equity between patients with only minimum losses of efficiency. This dynamic admission policy would seem to be a superior in maximizing case-flow. These results may be generalized to other surgical ICUs.

Blended learning in surgery using the Inmedea Simulator.

PubMed

Funke, Katrin; Bonrath, Esther; Mardin, Wolf Arif; Becker, Jan Carl; Haier, Joerg; Senninger, Norbert; Vowinkel, Thorsten; Hoelzen, Jens Peter; Mees, Soeren Torge

2013-02-01

Recently, medical education in surgery has experienced several modifications. We have implemented a blended learning module in our teaching curriculum to evaluate its effectiveness, applicability, and acceptance in surgical education. In this prospective study, the traditional face-to-face learning of our teaching curriculum for fourth-year medical students (n = 116) was augmented by the Inmedea Simulator, a web-based E-learning system, with six virtual patient cases. Student results were documented by the system and learning success was determined by comparing patient cases with comparable diseases (second and sixth case). The acceptance among the students was evaluated with a questionnaire. After using the Inmedea Simulator, correct diagnoses were found significantly (P < 0.05) more often, while an incomplete diagnostic was seen significantly (P < 0.05) less often. Significant overall improvement (P < 0.05) was seen in sixth case (62.3 ± 5.6 %) vs. second case (53.9 ± 5.6 %). The questionnaire revealed that our students enjoyed the surgical seminar (score 2.1 ± 1.5) and preferred blended learning (score 2.5 ± 1.2) to conventional teaching. The blended learning approach using the Inmedea Simulator was highly appreciated by our medical students and resulted in a significant learning success. Blended learning appears to be a suitable tool to complement traditional teaching in surgery.

Preoperative simulation for the planning of microsurgical clipping of intracranial aneurysms.

PubMed

Marinho, Paulo; Vermandel, Maximilien; Bourgeois, Philippe; Lejeune, Jean-Paul; Mordon, Serge; Thines, Laurent

2014-12-01

The safety and success of intracranial aneurysm (IA) surgery could be improved through the dedicated application of simulation covering the procedure from the 3-dimensional (3D) description of the surgical scene to the visual representation of the clip application. We aimed in this study to validate the technical feasibility and clinical relevance of such a protocol. All patients preoperatively underwent 3D magnetic resonance imaging and 3D computed tomography angiography to build 3D reconstructions of the brain, cerebral arteries, and surrounding cranial bone. These 3D models were segmented and merged using Osirix, a DICOM image processing application. This provided the surgical scene that was subsequently imported into Blender, a modeling platform for 3D animation. Digitized clips and appliers could then be manipulated in the virtual operative environment, allowing the visual simulation of clipping. This simulation protocol was assessed in a series of 10 IAs by 2 neurosurgeons. The protocol was feasible in all patients. The visual similarity between the surgical scene and the operative view was excellent in 100% of the cases, and the identification of the vascular structures was accurate in 90% of the cases. The neurosurgeons found the simulation helpful for planning the surgical approach (ie, the bone flap, cisternal opening, and arterial tree exposure) in 100% of the cases. The correct number of final clip(s) needed was predicted from the simulation in 90% of the cases. The preoperatively expected characteristics of the optimal clip(s) (ie, their number, shape, size, and orientation) were validated during surgery in 80% of the cases. This study confirmed that visual simulation of IA clipping based on the processing of high-resolution 3D imaging can be effective. This is a new and important step toward the development of a more sophisticated integrated simulation platform dedicated to cerebrovascular surgery.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larner, J.

In this interactive session, lung SBRT patient cases will be presented to highlight real-world considerations for ensuring safe and accurate treatment delivery. An expert panel of speakers will discuss challenges specific to lung SBRT including patient selection, patient immobilization techniques, 4D CT simulation and respiratory motion management, target delineation for treatment planning, online treatment alignment, and established prescription regimens and OAR dose limits. Practical examples of cases, including the patient flow thought the clinical process are presented and audience participation will be encouraged. This panel session is designed to provide case demonstration and review for lung SBRT in terms ofmore » (1) clinical appropriateness in patient selection, (2) strategies for simulation, including 4D and respiratory motion management, and (3) applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent, and (4) image guidance in treatment delivery. Learning Objectives: Understand the established requirements for patient selection in lung SBRT Become familiar with the various immobilization strategies for lung SBRT, including technology for respiratory motion management Understand the benefits and pitfalls of applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent determination for lung SBRT Understand established prescription regimes and OAR dose limits.« less

Threats from patients and their effects on medical decision making: a cross-sectional, randomised trial.

PubMed

Kristiansen, I S; Førde, O H; Aasland, O; Hotvedt, R; Johnsen, R; Førde, R

2001-04-21

Negative experiences are not uncommon among doctors in Norway. Our aim was to find out about the various types of negative reactions (eg, complaints, negative exposure to the media, financial claims, and notification to the police) received by physicians from patients or relatives in response to treatment, to identify their cause, and to study their effects on subsequent clinical decisions. We posted questionnaires about negative reactions of patients to a random sample (n=1260) of Norwegian doctors. Each doctor was additionally sent five written case simulations and asked to choose one of several proposed clinical strategies. Half (630) the physicians received cases containing threats from the patient or their relatives. 988 (78%) physicians returned the questionnaire, 463 (47%) of whom reported negative experiences. Such experiences were reported more frequently by men (357 [51%]) and family physicians (157 [58%]) than by other participants. Negative experiences did not affect choice of strategy for case simulations. For the first case, chest pain, 217 (44%) physicians presented with a threat chose a defensive strategy compared with 145 (30%) of those who were not (difference 14%; 95% CI 8-20). For the second case, a headache case, the corresponding numbers were 278 (57%) and 118 (25%) (32%; 26-38). Physician age, sex, specialty, or experience of negative reactions of patients did not alter the effect of threats received during our study. Negative experiences do not affect subsequent decision making. However, doctors do comply with wishes from patients or relatives when presented with direct threats.

Case-based tutoring from a medical knowledge base.

PubMed

Chin, H L; Cooper, G F

1989-01-01

The past decade has seen the emergence of programs that make use of large knowledge bases to assist physicians in diagnosis within the general field of internal medicine. One such program, Internist-I, contains knowledge about over 600 diseases, covering a significant proportion of internal medicine. This paper describes the process of converting a subset of this knowledge base--in the area of cardiovascular diseases--into a probabilistic format, and the use of this resulting knowledge base to teach medical diagnostic knowledge. The system (called KBSimulator--for Knowledge-Based patient Simulator) generates simulated patient cases and uses these cases as a focal point from which to teach medical knowledge. This project demonstrates the feasibility of building an intelligent, flexible instructional system that uses a knowledge base constructed primarily for medical diagnosis.

Three-Dimensional Imaging in Rhinoplasty: A Comparison of the Simulated versus Actual Result.

PubMed

Persing, Sarah; Timberlake, Andrew; Madari, Sarika; Steinbacher, Derek

2018-05-22

Computer imaging has become increasingly popular for rhinoplasty. Three-dimensional (3D) analysis permits a more comprehensive view from multiple vantage points. However, the predictability and concordance between the simulated and actual result have not been morphometrically studied. The purpose of this study was to aesthetically and quantitatively compare the simulated to actual rhinoplasty result. A retrospective review of 3D images (VECTRA, Canfield) for rhinoplasty patients was performed. Images (preop, simulated, and actual) were randomized. A blinded panel of physicians rated the images (1 = poor, 5 = excellent). The image series considered "best" was also recorded. A quantitative assessment of nasolabial angle and tip projection was compared. Paired and two-sample t tests were performed for statistical analysis (P < 0.05 as significant). Forty patients were included. 67.5% of preoperative images were rated as poor (mean = 1.7). The simulation received a mean score of 2.9 (good in 60% of cases). 82.5% of actual cases were rated good to excellent (mean 3.4) (P < 0.001). Overall, the panel significantly preferred the actual postoperative result in 77.5% of cases compared to the simulation in 22.5% of cases (P < 0.001). The actual nasal tip was more projected compared to the simulations for both males and females. There was no significant difference in nasal tip rotation between simulated and postoperative groups. 3D simulation is a powerful communication and planning tool in rhinoplasty. In this study, the actual result was deemed more aesthetic than the simulated image. Surgeon experience is important to translate the plan and achieve favorable postoperative results. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Use of multiple patient simulators to enhance prioritizing and delegating skills for senior nursing students.

PubMed

Kaplan, Barbara; Ura, Darla

2010-07-01

The student clinical experience is rich, yet challenges arise in providing experiences where leadership skills can be developed and used in nursing practice. To increase student confidence and enhance student ability to safely and effectively prioritize, delegate, and implement care for numerous patients, a simulation-based learning (SBL) experience was developed. The SBL experience involves multiple patient simulators, case study analysis, and a debriefing session. Ninety-seven senior nursing students participated in this program. Students reported through Likert surveys to either "agree" or "strongly agree" that the SBL was well organized (87%, n = 84), prompted realistic expectations (59%, n = 57), the scenarios were believable (73%, n = 71), case studies increased understanding (66%, n = 64), and that the SBL experience increased understanding of prioritizing and delegating care (69%, n = 67). Seventy-eight percent (n = 76) reported "more confidence in ability to work as a team" and 55% (n = 52) reported "more confidence in prioritizing and delegating care." Copyright 2010, SLACK Incorporated.

Case-Based Learning for Orofacial Pain and Temporomandibular Disorders.

ERIC Educational Resources Information Center

Clark, Glenn T.; And Others

1993-01-01

The use of interactive computer-based simulation of cases of chronic orofacial pain and temporomandibular joint disfunction patients for clinical dental education is described. Its application as a voluntary study aid in a third-year dental course is evaluated for effectiveness and for time factors in case completion. (MSE)

Interactive simulator for e-Learning environments: a teaching software for health care professionals.

PubMed

De Lazzari, Claudio; Genuini, Igino; Pisanelli, Domenico M; D'Ambrosi, Alessandra; Fedele, Francesco

2014-12-18

There is an established tradition of cardiovascular simulation tools, but the application of this kind of technology in the e-Learning arena is a novel approach. This paper presents an e-Learning environment aimed at teaching the interaction of cardiovascular and lung systems to health-care professionals. Heart-lung interaction must be analyzed while assisting patients with severe respiratory problems or with heart failure in intensive care unit. Such patients can be assisted by mechanical ventilatory assistance or by thoracic artificial lung."In silico" cardiovascular simulator was experimented during a training course given to graduate students of the School of Specialization in Cardiology at 'Sapienza' University in Rome.The training course employed CARDIOSIM©: a numerical simulator of the cardiovascular system. Such simulator is able to reproduce pathophysiological conditions of patients affected by cardiovascular and/or lung disease. In order to study the interactions among the cardiovascular system, the natural lung and the thoracic artificial lung (TAL), the numerical model of this device has been implemented. After having reproduced a patient's pathological condition, TAL model was applied in parallel and hybrid model during the training course.Results obtained during the training course show that TAL parallel assistance reduces right ventricular end systolic (diastolic) volume, but increases left ventricular end systolic (diastolic) volume. The percentage changes induced by hybrid TAL assistance on haemodynamic variables are lower than those produced by parallel assistance. Only in the case of the mean pulmonary arterial pressure, there is a percentage reduction which, in case of hybrid assistance, is greater (about 40%) than in case of parallel assistance (20-30%).At the end of the course, a short questionnaire was submitted to students in order to assess the quality of the course. The feedback obtained was positive, showing good results with respect to the degree of students' learning and the ease of use of the software simulator.

Are metastases from metastases clinical relevant? Computer modelling of cancer spread in a case of hepatocellular carcinoma.

PubMed

Bethge, Anja; Schumacher, Udo; Wree, Andreas; Wedemann, Gero

2012-01-01

Metastasis formation remains an enigmatic process and one of the main questions recently asked is whether metastases are able to generate further metastases. Different models have been proposed to answer this question; however, their clinical significance remains unclear. Therefore a computer model was developed that permits comparison of the different models quantitatively with clinical data and that additionally predicts the outcome of treatment interventions. The computer model is based on discrete events simulation approach. On the basis of a case from an untreated patient with hepatocellular carcinoma and its multiple metastases in the liver, it was evaluated whether metastases are able to metastasise and in particular if late disseminated tumour cells are still capable to form metastases. Additionally, the resection of the primary tumour was simulated. The simulation results were compared with clinical data. The simulation results reveal that the number of metastases varies significantly between scenarios where metastases metastasise and scenarios where they do not. In contrast, the total tumour mass is nearly unaffected by the two different modes of metastasis formation. Furthermore, the results provide evidence that metastasis formation is an early event and that late disseminated tumour cells are still capable of forming metastases. Simulations also allow estimating how the resection of the primary tumour delays the patient's death. The simulation results indicate that for this particular case of a hepatocellular carcinoma late metastases, i.e., metastases from metastases, are irrelevant in terms of total tumour mass. Hence metastases seeded from metastases are clinically irrelevant in our model system. Only the first metastases seeded from the primary tumour contribute significantly to the tumour burden and thus cause the patient's death.

Transitional Flow in an Arteriovenous Fistula: Effect of Wall Distensibility

NASA Astrophysics Data System (ADS)

McGah, Patrick; Leotta, Daniel; Beach, Kirk; Aliseda, Alberto

2012-11-01

Arteriovenous fistulae are created surgically to provide adequate access for dialysis in patients with end-stage renal disease. Transitional flow and the subsequent pressure and shear stress fluctuations are thought to be causative in the fistula failure. Since 50% of fistulae require surgical intervention before year one, understanding the altered hemodynamic stresses is an important step toward improving clinical outcomes. We perform numerical simulations of a patient-specific model of a functioning fistula reconstructed from 3D ultrasound scans. Rigid wall simulations and fluid-structure interaction simulations using an in-house finite element solver for the wall deformations were performed and compared. In both the rigid and distensible wall cases, transitional flow is computed in fistula as evidenced by aperiodic high frequency velocity and pressure fluctuations. The spectrum of the fluctuations is much more narrow-banded in the distensible case, however, suggesting a partial stabilizing effect by the vessel elasticity. As a result, the distensible wall simulations predict shear stresses that are systematically 10-30% lower than the rigid cases. We propose a possible mechanism for stabilization involving the phase lag in the fluid work needed to deform the vessel wall. Support from an NIDDK R21 - DK08-1823.

A simulation for teaching the basic and clinical science of fluid therapy.

PubMed

Rawson, Richard E; Dispensa, Marilyn E; Goldstein, Richard E; Nicholson, Kimberley W; Vidal, Noni Korf

2009-09-01

The course "Management of Fluid and Electrolyte Disorders" is an applied physiology course taught using lectures and paper-based cases. The course approaches fluid therapy from both basic science and clinical perspectives. While paper cases provide a basis for application of basic science concepts, they lack key components of genuine clinical cases that, by nature, are diverse, change over time, and respond in unique ways to therapeutic interventions. We developed a dynamic model using STELLA software that simulates normal and abnormal fluid and electrolyte balance in the dog. Students interact, not with the underlying model, but with a user interface that provides sufficient data (skin turgor, chemistry panel, etc.) for the clinical assessment of patients and an opportunity for treatment. Students administer fluids and supplements, and the model responds in "real time," requiring regular reassessment and, potentially, adaptation of the treatment strategy. The level of success is determined by clinical outcome, including improvement, deterioration, or death. We expected that the simulated cases could be used to teach both the clinical and basic science of fluid therapy. The simulation provides exposure to a realistic clinical environment, and students tend to focus on this aspect of the simulation while, for the most part, ignoring an exploration of the underlying physiological basis for patient responses. We discuss how the instructor's expertise can provide sufficient support, feedback, and scaffolding so that students can extract maximum understanding of the basic science in the context of assessing and treating at the clinical level.

Virtual reality: emerging role of simulation training in vascular access.

PubMed

Davidson, Ingemar J A; Lok, Charmaine; Dolmatch, Bart; Gallieni, Maurizio; Nolen, Billy; Pittiruti, Mauro; Ross, John; Slakey, Douglas

2012-11-01

Evolving new technologies in vascular access mandate increased attention to patient safety; an often overlooked yet valuable training tool is simulation. For the end-stage renal disease patient, simulation tools are effective for all aspects of creating access for peritoneal dialysis and hemodialysis. Based on aviation principles, known as crew resource management, we place equal emphasis on team training as individual training to improve interactions between team members and systems, cumulating in improved safety. Simulation allows for environmental control and standardized procedures, letting the trainee practice and correct mistakes without harm to patients, compared with traditional patient-based training. Vascular access simulators range from suture devices, to pressurized tunneled conduits for needle cannulation, to computer-based interventional simulators. Simulation training includes simulated case learning, root cause analysis of adverse outcomes, and continual update and refinement of concepts. Implementation of effective human to complex systems interaction in end-stage renal disease patients involves a change in institutional culture. Three concepts discussed in this article are as follows: (1) the need for user-friendly systems and technology to enhance performance, (2) the necessity for members to both train and work together as a team, and (3) the team assigned to use the system must test and practice it to a proficient level before safely using the system on patients. Copyright © 2012 Elsevier Inc. All rights reserved.

The impact of leadership and team behavior on standard of care delivered during human patient simulation: a pilot study for undergraduate medical students.

PubMed

Carlson, Jim; Min, Elana; Bridges, Diane

2009-01-01

Methodology to train team behavior during simulation has received increased attention, but standard performance measures are lacking, especially at the undergraduate level. Our purposes were to develop a reliable team behavior measurement tool and explore the relationship between team behavior and the delivery of an appropriate standard of care specific to the simulated case. Authors developed a unique team measurement tool based on previous work. Trainees participated in a simulated event involving the presentation of acute dyspnea. Performance was rated by separate raters using the team behavior measurement tool. Interrater reliability was assessed. The relationship between team behavior and the standard of care delivered was explored. The instrument proved to be reliable for this case and group of raters. Team behaviors had a positive relationship with the standard of medical care delivered specific to the simulated case. The methods used provide a possible method for training and assessing team performance during simulation.

Point-of-care ultrasound education: the increasing role of simulation and multimedia resources.

PubMed

Lewiss, Resa E; Hoffmann, Beatrice; Beaulieu, Yanick; Phelan, Mary Beth

2014-01-01

This article reviews the current technology, literature, teaching models, and methods associated with simulation-based point-of-care ultrasound training. Patient simulation appears particularly well suited for learning point-of-care ultrasound, which is a required core competency for emergency medicine and other specialties. Work hour limitations have reduced the opportunities for clinical practice, and simulation enables practicing a skill multiple times before it may be used on patients. Ultrasound simulators can be categorized into 2 groups: low and high fidelity. Low-fidelity simulators are usually static simulators, meaning that they have nonchanging anatomic examples for sonographic practice. Advantages are that the model may be reused over time, and some simulators can be homemade. High-fidelity simulators are usually high-tech and frequently consist of many computer-generated cases of virtual sonographic anatomy that can be scanned with a mock probe. This type of equipment is produced commercially and is more expensive. High-fidelity simulators provide students with an active and safe learning environment and make a reproducible standardized assessment of many different ultrasound cases possible. The advantages and disadvantages of using low- versus high-fidelity simulators are reviewed. An additional concept used in simulation-based ultrasound training is blended learning. Blended learning may include face-to-face or online learning often in combination with a learning management system. Increasingly, with simulation and Web-based learning technologies, tools are now available to medical educators for the standardization of both ultrasound skills training and competency assessment.

Clinical Simulation: A Protocol for Evaluation of Mobile Technology.

PubMed

Mather, Carey; Jensen, Sanne; Cummings, Elizabeth

2017-01-01

For mobile technology to be accepted at point of care in healthcare environments there is a need to demonstrate benefits whilst ameliorating the risks and challenges. To provide a standardised approach to evaluation of mobile technology a simulation protocol was developed to provide guidance for its use in healthcare environments. Simulated conditions provide the opportunity to assess intended and unintended consequences and identify potential workarounds when using technology. The protocol can also be used to demonstrate the importance of the development of digital professionalism by end-users prior to students entering the clinical practice setting. The mobile technology protocol was adapted from a health information systems protocol developed and used at the ITX Lab, Denmark for use in other simulation laboratories. Use case scenarios were developed to enable evaluation of mobile technology for mobile learning of nurses, nurse supervisors, students and patients. The scenarios can be used in a range of simulated environments including hospital bedside, outpatient clinic or community settings. A case study exemplar of a nurse and patient is included to demonstrate how the mobile technology protocol can be applied.

Analysis of Expert Diagnosis of a Computer Simulation of Congenital Heart Disease

ERIC Educational Resources Information Center

Johnson, Paul E.; And Others

1975-01-01

It is concluded that while behavior of experts in the hospital and clinic is the primary means of evaluating successful student performance, computer simulations of patient cases offer the opportunity to use expert data in the calibration of student error. (Editor)

Carcinomas of the urinary bladder simulating malignant lymphoma. A report of five cases.

PubMed

Zukerberg, L R; Harris, N L; Young, R H

1991-06-01

We report five carcinomas of the urinary bladder, four of them transitional cell carcinomas and one undifferentiated carcinoma, with unusual features that have received little or no comment in the literature and may be the cause of diagnostic difficulty because of their possible confusion with malignant lymphoma. Four patients were male and one female. They ranged from 61 to 76 years of age. Three tumors from these patients had a prominent (2 cases) or massive (1 case) lymphoid infiltrate that partially obscured the invasive carcinoma in two cases and largely obscured it in the third case, which closely resembled a lymphoepithelioma. The diagnosis of malignant lymphoma was only excluded with confidence in the last case after thorough immunohistochemical study. The lymphoid infiltrate was composed of numerous T-cells (UCHL-1 and Leu 22 positive) and polytypic plasma cells with admixed eosinophils; occasional germinal centers were present in one case. The tumors were deeply invasive in two patients, one of whom is alive with no evidence of disease 4 years after treatment with chemotherapy and radiation therapy; the other two cases are too recent for meaningful follow-up. Two other transitional cell carcinomas had diffuse patterns that simulated lymphoma or plasmacytoma. Recognition of these patterns of vesical carcinoma is important in order to avoid the misdiagnosis of the very rare malignant lymphoma of the urinary bladder.

Time-resolved versus time-integrated portal dosimetry: the role of an object’s position with respect to the isocenter in volumetric modulated arc therapy

NASA Astrophysics Data System (ADS)

Schyns, Lotte E. J. R.; Persoon, Lucas C. G. G.; Podesta, Mark; van Elmpt, Wouter J. C.; Verhaegen, Frank

2016-05-01

The aim of this work is to compare time-resolved (TR) and time-integrated (TI) portal dosimetry, focussing on the role of an object’s position with respect to the isocenter in volumetric modulated arc therapy (VMAT). Portal dose images (PDIs) are simulated and measured for different cases: a sphere (1), a bovine bone (2) and a patient geometry (3). For the simulated case (1) and the experimental case (2), several transformations are applied at different off-axis positions. In the patient case (3), three simple plans with different isocenters are created and pleural effusion is simulated in the patient. The PDIs before and after the sphere transformations, as well as the PDIs with and without simulated pleural effusion, are compared using a TI and TR gamma analysis. In addition, the performance of the TI and TR gamma analyses for the detection of real geometric changes in patients treated with clinical plans is investigated and a correlation analysis is performed between gamma fail rates and differences in dose volume histogram (DVH) metrics. The TI gamma analysis can show large differences in gamma fail rates for the same transformation at different off-axis positions (or for different plan isocenters). The TR gamma analysis, however, shows consistent gamma fail rates. For the detection of real geometric changes in patients treated with clinical plans, the TR gamma analysis has a higher sensitivity than the TI gamma analysis. However, the specificity for the TR gamma analysis is lower than for the TI gamma analysis. Both the TI and TR gamma fail rates show no correlation with changes in DVH metrics. This work shows that TR portal dosimetry is fundamentally superior to TI portal dosimetry, because it removes the strong dependence of the gamma fail rate on the off-axis position/plan isocenter. However, for 2D TR portal dosimetry, it is still difficult to interpret gamma fail rates in terms of changes in DVH metrics for patients treated with VMAT.

USim: A New Device and App for Case-Specific, Intraoperative Ultrasound Simulation and Rehearsal in Neurosurgery. A Preliminary Study.

PubMed

Perin, Alessandro; Prada, Francesco Ugo; Moraldo, Michela; Schiappacasse, Andrea; Galbiati, Tommaso Francesco; Gambatesa, Enrico; d'Orio, Piergiorgio; Riker, Nicole Irene; Basso, Curzio; Santoro, Matteo; Meling, Torstein Ragnar; Schaller, Karl; DiMeco, Francesco

2018-05-01

Intraoperative ultrasound (iUS) is an excellent aid for neurosurgeons to perform better and safer operations thanks to real time, continuous, and high-quality intraoperative visualization. To develop an innovative training method to teach how to perform iUS in neurosurgery. Patients undergoing surgery for different brain or spine lesions were iUS scanned (before opening the dura) in order to arrange a collection of 3-dimensional, US images; this set of data was matched and paired to preoperatively acquired magnetic resonance images in order to create a library of neurosurgical cases to be studied offline for training and rehearsal purposes. This new iUS training approach was preliminarily tested on 14 European neurosurgery residents, who participated at the 2016 European Association of Neurosurgical Societies Training Course (Sofia, Bulgaria). USim was developed by Camelot and the Besta NeuroSim Center as a dedicated app that transforms any smartphone into a "virtual US probe," in order to simulate iUS applied to neurosurgery on a series of anonymized, patient-specific cases of different central nervous system tumors (eg, gliomas, metastases, meningiomas) for education, simulation, and rehearsal purposes. USim proved to be easy to use and allowed residents to quickly learn to handle a US probe and interpret iUS semiotics. USim could help neurosurgeons learn neurosurgical iUS safely. Furthermore, neurosurgeons could simulate many cases, of different brain/spinal cord tumors, that resemble the specific cases they have to operate on. Finally, the library of cases would be continuously updated, upgraded, and made available to neurosurgeons.

An acute interprofessional simulation experience for occupational and physical therapy students: Key findings from a survey study.

PubMed

Thomas, Erin M; Rybski, Melinda F; Apke, Tonya L; Kegelmeyer, Deb A; Kloos, Anne D

2017-05-01

Due to the fast pace and high complexity of managing patients in intensive and acute care units (ICUs), healthcare students often feel challenged and unprepared to practice in this environment. Simulations and standardised patients provide "hands-on" learning experiences that are realistic and help students to gain competence and confidence. This study examined the impact of an intensive case simulation laboratory using a patient simulator and standardised patients on students' perceptions of their confidence and preparedness to work in acute care settings. Second-year Masters of Occupational Therapy (MOT; n = 127) and Doctor of Physical Therapy (DPT; n = 105) students participated in a three-hour intensive care simulation laboratory comprised of four stations that were designed to simulate common ICU patient care scenarios. Data analysed were student pre- and post-simulation surveys and written comments, and clinical instructors' (CIs; n = 51) ratings on DPT students' preparedness and confidence within the first two weeks of their acute care internships obtained after the laboratory. There was a significant increase for DPT (p < 0.0001) and MOT (p < 0.10) students in median ratings of how prepared they felt to practice in acute care settings following the ICU simulation compared to before the laboratory. CIs rated the DPT students as either prepared or very prepared for and moderately confident or very confident in the acute care setting. The use of simulation training using standardised patients and patient simulators was beneficial in increasing student confidence and preparing OT and PT students to practice in the acute care setting. Health professional educators should consider using an interprofessional simulation experience to improve their students' confidence and preparedness to provide appropriate care in the acute setting.

Physician gender and patient centered communication: the moderating effect of psychosocial and biomedical case characteristics.

PubMed

Shin, Dong Wook; Roter, Debra L; Roh, Yong Kyun; Hahm, Sang Keun; Cho, BeLong; Park, Hoon-Ki

2015-01-01

Female physicians have a more patient-centered communication style than their male counterparts; however, few studies have investigated how the biomedical or psychosocial nature of a patient diagnosis might moderate this relationship. Seventy six 3rd year residents (50 male and 26 females) seeking board certification from the Korean Academy of Family Medicine participated in the 2013 Clinical Practice Examination by conducting two simulated patient (SP) interviews, one presenting a largely psychosocial case and the other largely biomedical. The interview recordings were coded with the Roter Interaction Analysis System (RIAS). Female physicians and their SPs engaged in more dialog than male physicians in both cases. Female physicians were more patient-centered than males for the psychosocial case (t = -3.24, P < 0.05), however, their scores did not differ for the biomedical case. In multivariate analysis, a significant interaction between physician gender and case (z = -3.90, P < 0.001) similarly demonstrated greater female patient-centeredness only for the predominantly psychosocial case. Case characteristics moderated the association between physician gender and patient-centeredness. Case characteristics need to be considered in future research on the association of physician gender and the patient-centered communication, as well as in the tailoring of physician communication training. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

A robustness test of the braided device foreshortening algorithm

NASA Astrophysics Data System (ADS)

Moyano, Raquel Kale; Fernandez, Hector; Macho, Juan M.; Blasco, Jordi; San Roman, Luis; Narata, Ana Paula; Larrabide, Ignacio

2017-11-01

Different computational methods have been recently proposed to simulate the virtual deployment of a braided stent inside a patient vasculature. Those methods are primarily based on the segmentation of the region of interest to obtain the local vessel morphology descriptors. The goal of this work is to evaluate the influence of the segmentation quality on the method named "Braided Device Foreshortening" (BDF). METHODS: We used the 3DRA images of 10 aneurysmatic patients (cases). The cases were segmented by applying a marching cubes algorithm with a broad range of thresholds in order to generate 10 surface models each. We selected a braided device to apply the BDF algorithm to each surface model. The range of the computed flow diverter lengths for each case was obtained to calculate the variability of the method against the threshold segmentation values. RESULTS: An evaluation study over 10 clinical cases indicates that the final length of the deployed flow diverter in each vessel model is stable, shielding maximum difference of 11.19% in vessel diameter and maximum of 9.14% in the simulated stent length for the threshold values. The average coefficient of variation was found to be 4.08 %. CONCLUSION: A study evaluating how the threshold segmentation affects the simulated length of the deployed FD, was presented. The segmentation algorithm used to segment intracranial aneurysm 3D angiography images presents small variation in the resulting stent simulation.

MO-E-BRB-03: Panel Member

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salter, B.

2016-06-15

In this interactive session, lung SBRT patient cases will be presented to highlight real-world considerations for ensuring safe and accurate treatment delivery. An expert panel of speakers will discuss challenges specific to lung SBRT including patient selection, patient immobilization techniques, 4D CT simulation and respiratory motion management, target delineation for treatment planning, online treatment alignment, and established prescription regimens and OAR dose limits. Practical examples of cases, including the patient flow thought the clinical process are presented and audience participation will be encouraged. This panel session is designed to provide case demonstration and review for lung SBRT in terms ofmore » (1) clinical appropriateness in patient selection, (2) strategies for simulation, including 4D and respiratory motion management, and (3) applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent, and (4) image guidance in treatment delivery. Learning Objectives: Understand the established requirements for patient selection in lung SBRT Become familiar with the various immobilization strategies for lung SBRT, including technology for respiratory motion management Understand the benefits and pitfalls of applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent determination for lung SBRT Understand established prescription regimes and OAR dose limits.« less

MO-E-BRB-01: Panel Member

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benedict, S.

2016-06-15

In this interactive session, lung SBRT patient cases will be presented to highlight real-world considerations for ensuring safe and accurate treatment delivery. An expert panel of speakers will discuss challenges specific to lung SBRT including patient selection, patient immobilization techniques, 4D CT simulation and respiratory motion management, target delineation for treatment planning, online treatment alignment, and established prescription regimens and OAR dose limits. Practical examples of cases, including the patient flow thought the clinical process are presented and audience participation will be encouraged. This panel session is designed to provide case demonstration and review for lung SBRT in terms ofmore » (1) clinical appropriateness in patient selection, (2) strategies for simulation, including 4D and respiratory motion management, and (3) applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent, and (4) image guidance in treatment delivery. Learning Objectives: Understand the established requirements for patient selection in lung SBRT Become familiar with the various immobilization strategies for lung SBRT, including technology for respiratory motion management Understand the benefits and pitfalls of applying multi imaging modality (4D CT imaging, MRI, PET) for tumor volume delineation and motion extent determination for lung SBRT Understand established prescription regimes and OAR dose limits.« less

Incidence and admission rates for severe malaria and their impact on mortality in Africa.

PubMed

Camponovo, Flavia; Bever, Caitlin A; Galactionova, Katya; Smith, Thomas; Penny, Melissa A

2017-01-03

Appropriate treatment of life-threatening Plasmodium falciparum malaria requires in-patient care. Although the proportion of severe cases accessing in-patient care in endemic settings strongly affects overall case fatality rates and thus disease burden, this proportion is generally unknown. At present, estimates of malaria mortality are driven by prevalence or overall clinical incidence data, ignoring differences in case fatality resulting from variations in access. Consequently, the overall impact of preventive interventions on disease burden have not been validly compared with those of improvements in access to case management or its quality. Using a simulation-based approach, severe malaria admission rates and the subsequent severe malaria disease and mortality rates for 41 malaria endemic countries of sub-Saharan Africa were estimated. Country differences in transmission and health care settings were captured by use of high spatial resolution data on demographics and falciparum malaria prevalence, as well as national level estimates of effective coverage of treatment for uncomplicated malaria. Reported and modelled estimates of cases, admissions and malaria deaths from the World Malaria Report, along with predicted burden from simulations, were combined to provide revised estimates of access to in-patient care and case fatality rates. There is substantial variation between countries' in-patient admission rates and estimated levels of case fatality rates. It was found that for many African countries, most patients admitted for in-patient treatment would not meet strict criteria for severe disease and that for some countries only a small proportion of the total severe cases are admitted. Estimates are highly sensitive to the assumed community case fatality rates. Re-estimation of national level malaria mortality rates suggests that there is substantial burden attributable to inefficient in-patient access and treatment of severe disease. The model-based methods proposed here offer a standardized approach to estimate the numbers of severe malaria cases and deaths based on national level reporting, allowing for coverage of both curative and preventive interventions. This makes possible direct comparisons of the potential benefits of scaling-up either category of interventions. The profound uncertainties around these estimates highlight the need for better data.

Recent advancements in medical simulation: patient-specific virtual reality simulation.

PubMed

Willaert, Willem I M; Aggarwal, Rajesh; Van Herzeele, Isabelle; Cheshire, Nicholas J; Vermassen, Frank E

2012-07-01

Patient-specific virtual reality simulation (PSVR) is a new technological advancement that allows practice of upcoming real operations and complements the established role of VR simulation as a generic training tool. This review describes current developments in PSVR and draws parallels with other high-stake industries, such as aviation, military, and sports. A review of the literature was performed using PubMed and Internet search engines to retrieve data relevant to PSVR in medicine. All reports pertaining to PSVR were included. Reports on simulators that did not incorporate a haptic interface device were excluded from the review. Fifteen reports described 12 simulators that enabled PSVR. Medical procedures in the field of laparoscopy, vascular surgery, orthopedics, neurosurgery, and plastic surgery were included. In all cases, source data was two-dimensional CT or MRI data. Face validity was most commonly reported. Only one (vascular) simulator had undergone face, content, and construct validity. Of the 12 simulators, 1 is commercialized and 11 are prototypes. Five simulators have been used in conjunction with real patient procedures. PSVR is a promising technological advance within medicine. The majority of simulators are still in the prototype phase. As further developments unfold, the validity of PSVR will have to be examined much like generic VR simulation for training purposes. Nonetheless, similar to the aviation, military, and sport industries, operative performance and patient safety may be enhanced by the application of this novel technology.

Teaching medical students a clinical approach to altered mental status: simulation enhances traditional curriculum

PubMed Central

Sperling, Jeremy D.; Clark, Sunday; Kang, Yoon

2013-01-01

Introduction Simulation-based medical education (SBME) is increasingly being utilized for teaching clinical skills in undergraduate medical education. Studies have evaluated the impact of adding SBME to third- and fourth-year curriculum; however, very little research has assessed its efficacy for teaching clinical skills in pre-clerkship coursework. To measure the impact of a simulation exercise during a pre-clinical curriculum, a simulation session was added to a pre-clerkship course at our medical school where the clinical approach to altered mental status (AMS) is traditionally taught using a lecture and an interactive case-based session in a small group format. The objective was to measure simulation's impact on students’ knowledge acquisition, comfort, and perceived competence with regards to the AMS patient. Methods AMS simulation exercises were added to the lecture and small group case sessions in June 2010 and 2011. Simulation sessions consisted of two clinical cases using a high-fidelity full-body simulator followed by a faculty debriefing after each case. Student participation in a simulation session was voluntary. Students who did and did not participate in a simulation session completed a post-test to assess knowledge and a survey to understand comfort and perceived competence in their approach to AMS. Results A total of 154 students completed the post-test and survey and 65 (42%) attended a simulation session. Post-test scores were higher in students who attended a simulation session compared to those who did not (p<0.001). Students who participated in a simulation session were more comfortable in their overall approach to treating AMS patients (p=0.05). They were also more likely to state that they could articulate a differential diagnosis (p=0.03), know what initial diagnostic tests are needed (p=0.01), and understand what interventions are useful in the first few minutes (p=0.003). Students who participated in a simulation session were more likely to find the overall AMS curriculum useful (p<0.001). Conclusion Students who participated in a simulation exercise performed better on a knowledge-based test and reported increased comfort and perceived competence in their clinical approach to AMS. SBME shows significant promise for teaching clinical skills to medical students during pre-clinical curriculum. PMID:23561054

Pre-operative simulation of pediatric mastoid surgery with 3D-printed temporal bone models.

PubMed

Rose, Austin S; Webster, Caroline E; Harrysson, Ola L A; Formeister, Eric J; Rawal, Rounak B; Iseli, Claire E

2015-05-01

As the process of additive manufacturing, or three-dimensional (3D) printing, has become more practical and affordable, a number of applications for the technology in the field of pediatric otolaryngology have been considered. One area of promise is temporal bone surgical simulation. Having previously developed a model for temporal bone surgical training using 3D printing, we sought to produce a patient-specific model for pre-operative simulation in pediatric otologic surgery. Our hypothesis was that the creation and pre-operative dissection of such a model was possible, and would demonstrate potential benefits in cases of abnormal temporal bone anatomy. In the case presented, an 11-year-old boy underwent a planned canal-wall-down (CWD) tympano-mastoidectomy for recurrent cholesteatoma preceded by a pre-operative surgical simulation using 3D-printed models of the temporal bone. The models were based on the child's pre-operative clinical CT scan and printed using multiple materials to simulate both bone and soft tissue structures. To help confirm the models as accurate representations of the child's anatomy, distances between various anatomic landmarks were measured and compared to the temporal bone CT scan and the 3D model. The simulation allowed the surgical team to appreciate the child's unusual temporal bone anatomy as well as any challenges that might arise in the safety of the temporal bone laboratory, prior to actual surgery in the operating room (OR). There was minimal variability, in terms of absolute distance (mm) and relative distance (%), in measurements between anatomic landmarks obtained from the patient intra-operatively, the pre-operative CT scan and the 3D-printed models. Accurate 3D temporal bone models can be rapidly produced based on clinical CT scans for pre-operative simulation of specific challenging otologic cases in children, potentially reducing medical errors and improving patient safety. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

[Clinical and communication simulation workshop for fellows in gastroenterology: the trainees' perspective].

PubMed

Lang, Alon; Melzer, Ehud; Bar-Meir, Simon; Eliakim, Rami; Ziv, Amitai

2006-11-01

The continuing development in computer-based medical simulators provides an ideal platform for simulator-assisted training programs for medical trainees. Computer-based endoscopic simulators provide a virtual reality environment for training endoscopic procedures. This study illustrates the use of a comprehensive training model combining the use of endoscopic simulators with simulated (actor) patients (SP). To evaluate the effectiveness of a comprehensive simulation workshop from the trainee perspective. Four case studies were developed with emphasis on communication skills. Three workshops with 10 fellows in each were conducted. During each workshop the trainees spent half of the time in SP case studies and the remaining half working with computerized endoscopic simulators with continuous guidance by an expert endoscopist. Questionnaires were completed by the fellows at the end of the workshop. Seventy percent of the fellows felt that the endoscopic simulator was close or very close to reality for gastroscopy and 63% for colonoscopy. Eighty eight percent thought the close guidance was important for the learning process with the simulator. Eighty percent felt that the case studies were an important learning experience for risk management. Further evaluation of multi-modality simulation workshops in gastroenterologist training is needed to identify how best to incorporate this form of instruction into training for gastroenterologists.

Re-use of pilot data and interim analysis of pivotal data in MRMC studies: a simulation study

NASA Astrophysics Data System (ADS)

Chen, Weijie; Samuelson, Frank; Sahiner, Berkman; Petrick, Nicholas

2017-03-01

Novel medical imaging devices are often evaluated with multi-reader multi-case (MRMC) studies in which radiologists read images of patient cases for a specified clinical task (e.g., cancer detection). A pilot study is often used to measure the effect size and variance parameters that are necessary for sizing a pivotal study (including sizing readers, non-diseased and diseased cases). Due to the practical difficulty of collecting patient cases or recruiting clinical readers, some investigators attempt to include the pilot data as part of their pivotal study. In other situations, some investigators attempt to perform an interim analysis of their pivotal study data based upon which the sample sizes may be re-estimated. Re-use of the pilot data or interim analyses of the pivotal data may inflate the type I error of the pivotal study. In this work, we use the Roe and Metz model to simulate MRMC data under the null hypothesis (i.e., two devices have equal diagnostic performance) and investigate the type I error rate for several practical designs involving re-use of pilot data or interim analysis of pivotal data. Our preliminary simulation results indicate that, under the simulation conditions we investigated, the inflation of type I error is none or only marginal for some design strategies (e.g., re-use of patient data without re-using readers, and size re-estimation without using the effect-size estimated in the interim analysis). Upon further verifications, these are potentially useful design methods in that they may help make a study less burdensome and have a better chance to succeed without substantial loss of the statistical rigor.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, C; Kim, J; Park, S

Purpose: Photon beams with energy higher than 10 MV interact with metal material in the primary barriers, where lead or steel have been widely used, neutrons can be generated. Monte Carlo simulations were performed to simulate the production of photoneutrons and the neutron shielding effect. Methods: For two photon beam energies, 15 MV and 18 MV, we simulated to strike metal sheets (steel and lead), and the ambient dose equivalents were calculated at the isocenter (in the patient plane) while delivering 1 Gy to the patient. For these cases, the thickness of the neutron shielding materials (Borated polyethylene (BPE) andmore » concrete) were simulated to reduce the patient exposure by neutron doses. Results: When 18 MV photons interact with the metal sheets in the primary barrier, the evaluated neutron doses at the isocenter inside the treatment vault were 48.7 µSv and 7.3 µSv for lead and steel, respectively. In case of 15 MV photons, the calculated neutron doses were 18.6 µSv and 0.6 µSv for lead and steel, respectively. The neutron dose delivered to the patient can be reduced to negligible levels by including a 10 cm thick sheet of BPE or 22 cm thick sheet of concrete. Conclusion: When bunker shielding is designed with a primary barrier including a metal sheet inside the wall for a high energy machine, proper neutron shielding should be constructed to avoid undesirable extra dose.« less

A systematic review of surgical skills transfer after simulation-based training: laparoscopic cholecystectomy and endoscopy.

PubMed

Dawe, Susan R; Windsor, John A; Broeders, Joris A J L; Cregan, Patrick C; Hewett, Peter J; Maddern, Guy J

2014-02-01

A systematic review to determine whether skills acquired through simulation-based training transfer to the operating room for the procedures of laparoscopic cholecystectomy and endoscopy. Simulation-based training assumes that skills are directly transferable to the operation room, but only a few studies have investigated the effect of simulation-based training on surgical performance. A systematic search strategy that was used in 2006 was updated to retrieve relevant studies. Inclusion of articles was determined using a predetermined protocol, independent assessment by 2 reviewers, and a final consensus decision. Seventeen randomized controlled trials and 3 nonrandomized comparative studies were included in this review. In most cases, simulation-based training was in addition to patient-based training programs. Only 2 studies directly compared simulation-based training in isolation with patient-based training. For laparoscopic cholecystectomy (n = 10 studies) and endoscopy (n = 10 studies), participants who reached simulation-based skills proficiency before undergoing patient-based assessment performed with higher global assessment scores and fewer errors in the operating room than their counterparts who did not receive simulation training. Not all parameters measured were improved. Two of the endoscopic studies compared simulation-based training in isolation with patient-based training with different results: for sigmoidoscopy, patient-based training was more effective, whereas for colonoscopy, simulation-based training was equally effective. Skills acquired by simulation-based training seem to be transferable to the operative setting for laparoscopic cholecystectomy and endoscopy. Future research will strengthen these conclusions by evaluating predetermined competency levels on the same simulators and using objective validated global rating scales to measure operative performance.

Using a human patient simulation mannequin to teach interdisciplinary team skills to pharmacy students.

PubMed

Fernandez, Rosemarie; Parker, Dennis; Kalus, James S; Miller, Douglas; Compton, Scott

2007-06-15

To determine the effectiveness and student acceptance of using a human patient simulation (HPS) training module focused on interdisciplinary teamwork skills. During their second-professional year, all pharmacy students were in enrolled in Principles of Pharmacotherapy 4: Cardiovascular Diseases and Patient Care Lab IV, a problem-based learning course. As part of the patient care laboratory, students participated in a simulated case of an acutely ill patient with a hypertensive emergency. During the simulation, students performed a history and physical examination. They then worked as a team to make treatment recommendations to the nursing and physician staff members. Following the exercise, a facilitated debriefing session was conducted. Students completed satisfaction surveys to assess the quality and effectiveness of the session. Over 98% of students agreed or strongly agreed that they learned material relevant to their current studies. When compared to student lectures, 90% of students felt that they learned clinical patient care better when using a HPS mannequin in simulated patient scenarios. HPS-based learning offers a realistic training experience through which clinical knowledge and interpersonal teamwork skills can be taught. Students enjoy the experience and find it relevant to their future practice. Simulation-based training may teach certain topics better than traditional lecture formats and as such could help to fill gaps in the current pharmacy curriculum.

Case and commentary: using simulation to address hierarchy issues during medical crises.

PubMed

Calhoun, Aaron W; Boone, Megan C; Miller, Karen H; Pian-Smith, May C M

2013-02-01

Medicine is hierarchical, and both positive and negative effects of this can be exposed and magnified during a crisis. Ideally, hierarchies function in an orderly manner, but when an inappropriate directive is given, the results can be disastrous unless team members are empowered to challenge the order. This article describes a case that uses misdirection and the possibility of simulated "death" to facilitate learning among experienced clinicians about the potentially deadly effects of an unchallenged, inappropriate order. The design of this case, however, raises additional questions regarding both ethics and psychological safety. The ethical concerns that surround the use of misdirection in simulation and the psychological ramifications of incorporating patient death in this context are explored in the commentary. We conclude with a discussion of debriefing strategies that can be used to promote psychological safety during potentially emotionally charged simulations and possible directions for future research.

Development of an Assessment for Entrustable Professional Activity (EPA) 10: Emergent Patient Management.

PubMed

Thompson, Laura R; Leung, Cynthia G; Green, Brad; Lipps, Jonathan; Schaffernocker, Troy; Ledford, Cynthia; Davis, John; Way, David P; Kman, Nicholas E

2017-01-01

Medical schools in the United States are encouraged to prepare and certify the entrustment of medical students to perform 13 core entrustable professional activities (EPAs) prior to graduation. Entrustment is defined as the informed belief that the learner is qualified to autonomously perform specific patient-care activities. Core EPA-10 is the entrustment of a graduate to care for the emergent patient. The purpose of this project was to design a realistic performance assessment method for evaluating fourth-year medical students on EPA-10. First, we wrote five emergent patient case-scenarios that a medical trainee would likely confront in an acute care setting. Furthermore, we developed high-fidelity simulations to realistically portray these patient case scenarios. Finally, we designed a performance assessment instrument to evaluate the medical student's performance on executing critical actions related to EPA-10 competencies. Critical actions included the following: triage skills, mustering the medical team, identifying causes of patient decompensation, and initiating care. Up to four students were involved with each case scenario; however, only the team leader was evaluated using the assessment instruments developed for each case. A total of 114 students participated in the EPA-10 assessment during their final year of medical school. Most students demonstrated competence in recognizing unstable vital signs (97%), engaging the team (93%), and making appropriate dispositions (92%). Almost 87% of the students were rated as having reached entrustment to manage the care of an emergent patient (99 of 114). Inter-rater reliability varied by case scenario, ranging from moderate to near-perfect agreement. Three of five case-scenario assessment instruments contained items that were internally consistent at measuring student performance. Additionally, the individual item scores for these case scenarios were highly correlated with the global entrustment decision. High-fidelity simulation showed good potential for effective assessment of medical student entrustment of caring for the emergent patient. Preliminary evidence from this pilot project suggests content validity of most cases and associated checklist items. The assessments also demonstrated moderately strong faculty inter-rater reliability.

Let's Talk Critical. Development and Evaluation of a Communication Skills Training Program for Critical Care Fellows.

PubMed

Hope, Aluko A; Hsieh, S Jean; Howes, Jennifer M; Keene, Adam B; Fausto, James A; Pinto, Priya A; Gong, Michelle Ng

2015-04-01

Although expert communication between intensive care unit clinicians with patients or surrogates improves patient- and family-centered outcomes, fellows in critical care medicine do not feel adequately trained to conduct family meetings. We aimed to develop, implement, and evaluate a communication skills program that could be easily integrated into a U.S. critical care fellowship. We developed four simulation cases that provided communication challenges that critical care fellows commonly face. For each case, we developed a list of directly observable tasks that could be used by faculty to evaluate fellows during each simulation. We developed a didactic curriculum of lectures/case discussions on topics related to palliative care, end-of-life care, communication skills, and bioethics; this month-long curriculum began and ended with the fellows leading family meetings in up to two simulated cases with direct observation by faculty who were not blinded to the timing of the simulation. Our primary measures of effectiveness were the fellows' self-reported change in comfort with leading family meetings after the program was completed and the quality of the communication as measured by the faculty evaluators during the family meeting simulations at the end of the month. Over 3 years, 31 critical care fellows participated in the program, 28 of whom participated in 101 family meeting simulations with direct feedback by faculty facilitators. Our trainees showed high rates of information disclosure during the simulated family meetings. During the simulations done at the end of the month compared with those done at the beginning, our fellows showed significantly improved rates in: (1) verbalizing an agenda for the meeting (64 vs. 41%; Chi-square, 5.27; P = 0.02), (2) summarizing what will be done for the patient (64 vs. 39%; Chi-square, 6.21; P = 0.01), and (3) providing a follow-up plan (60 vs. 37%; Chi-square, 5.2; P = 0.02). More than 95% of our participants (n = 27) reported feeling "slightly" or "much" more comfortable with discussing foregoing life-sustaining treatment and leading family discussions after the month-long curriculum. A communication skills program can be feasibly integrated into a critical care training program and is associated with improvements in fellows' skills and comfort with leading family meetings.

Let’s Talk Critical. Development and Evaluation of a Communication Skills Training Program for Critical Care Fellows

PubMed Central

Hsieh, S. Jean; Howes, Jennifer M.; Keene, Adam B.; Fausto, James A.; Pinto, Priya A.; Gong, Michelle Ng

2015-01-01

Rationale: Although expert communication between intensive care unit clinicians with patients or surrogates improves patient- and family-centered outcomes, fellows in critical care medicine do not feel adequately trained to conduct family meetings. Objectives: We aimed to develop, implement, and evaluate a communication skills program that could be easily integrated into a U.S. critical care fellowship. Methods: We developed four simulation cases that provided communication challenges that critical care fellows commonly face. For each case, we developed a list of directly observable tasks that could be used by faculty to evaluate fellows during each simulation. We developed a didactic curriculum of lectures/case discussions on topics related to palliative care, end-of-life care, communication skills, and bioethics; this month-long curriculum began and ended with the fellows leading family meetings in up to two simulated cases with direct observation by faculty who were not blinded to the timing of the simulation. Our primary measures of effectiveness were the fellows’ self-reported change in comfort with leading family meetings after the program was completed and the quality of the communication as measured by the faculty evaluators during the family meeting simulations at the end of the month. Measurements and Main Results: Over 3 years, 31 critical care fellows participated in the program, 28 of whom participated in 101 family meeting simulations with direct feedback by faculty facilitators. Our trainees showed high rates of information disclosure during the simulated family meetings. During the simulations done at the end of the month compared with those done at the beginning, our fellows showed significantly improved rates in: (1) verbalizing an agenda for the meeting (64 vs. 41%; Chi-square, 5.27; P = 0.02), (2) summarizing what will be done for the patient (64 vs. 39%; Chi-square, 6.21; P = 0.01), and (3) providing a follow-up plan (60 vs. 37%; Chi-square, 5.2; P = 0.02). More than 95% of our participants (n = 27) reported feeling “slightly” or “much” more comfortable with discussing foregoing life-sustaining treatment and leading family discussions after the month-long curriculum. Conclusions: A communication skills program can be feasibly integrated into a critical care training program and is associated with improvements in fellows’ skills and comfort with leading family meetings. PMID:25741996

Impact of crisis resource management simulation-based training for interprofessional and interdisciplinary teams: A systematic review.

PubMed

Fung, Lillia; Boet, Sylvain; Bould, M Dylan; Qosa, Haytham; Perrier, Laure; Tricco, Andrea; Tavares, Walter; Reeves, Scott

2015-01-01

Crisis resource management (CRM) abilities are important for different healthcare providers to effectively manage critical clinical events. This study aims to review the effectiveness of simulation-based CRM training for interprofessional and interdisciplinary teams compared to other instructional methods (e.g., didactics). Interprofessional teams are composed of several professions (e.g., nurse, physician, midwife) while interdisciplinary teams are composed of several disciplines from the same profession (e.g., cardiologist, anaesthesiologist, orthopaedist). Medline, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, and ERIC were searched using terms related to CRM, crisis management, crew resource management, teamwork, and simulation. Trials comparing simulation-based CRM team training versus any other methods of education were included. The educational interventions involved interprofessional or interdisciplinary healthcare teams. The initial search identified 7456 publications; 12 studies were included. Simulation-based CRM team training was associated with significant improvements in CRM skill acquisition in all but two studies when compared to didactic case-based CRM training or simulation without CRM training. Of the 12 included studies, one showed significant improvements in team behaviours in the workplace, while two studies demonstrated sustained reductions in adverse patient outcomes after a single simulation-based CRM team intervention. In conclusion, CRM simulation-based training for interprofessional and interdisciplinary teams show promise in teaching CRM in the simulator when compared to didactic case-based CRM education or simulation without CRM teaching. More research, however, is required to demonstrate transfer of learning to workplaces and potential impact on patient outcomes.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

PubMed Central

2010-01-01

Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. Methods The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. Results The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. Conclusions The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies. PMID:20584307

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients.

PubMed

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-06-28

Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.

Robotic intrafractional US guidance for liver SABR: System design, beam avoidance, and clinical imaging.

PubMed

Schlosser, Jeffrey; Gong, Ren Hui; Bruder, Ralf; Schweikard, Achim; Jang, Sungjune; Henrie, John; Kamaya, Aya; Koong, Albert; Chang, Daniel T; Hristov, Dimitre

2016-11-01

To present a system for robotic 4D ultrasound (US) imaging concurrent with radiotherapy beam delivery and estimate the proportion of liver stereotactic ablative body radiotherapy (SABR) cases in which robotic US image guidance can be deployed without interfering with clinically used VMAT beam configurations. The image guidance hardware comprises a 4D US machine, an optical tracking system for measuring US probe pose, and a custom-designed robot for acquiring hands-free US volumes. In software, a simulation environment incorporating the LINAC, couch, planning CT, and robotic US guidance hardware was developed. Placement of the robotic US hardware was guided by a target visibility map rendered on the CT surface by using the planning CT to simulate US propagation. The visibility map was validated in a prostate phantom and evaluated in patients by capturing live US from imaging positions suggested by the visibility map. In 20 liver SABR patients treated with VMAT, the simulation environment was used to virtually place the robotic hardware and US probe. Imaging targets were either planning target volumes (PTVs, range 5.9-679.5 ml) or gross tumor volumes (GTVs, range 0.9-343.4 ml). Presence or absence of mechanical interference with LINAC, couch, and patient body as well as interferences with treated beams was recorded. For PTV targets, robotic US guidance without mechanical interference was possible in 80% of the cases and guidance without beam interference was possible in 60% of the cases. For the smaller GTV targets, these proportions were 95% and 85%, respectively. GTV size (1/20), elongated shape (1/20), and depth (1/20) were the main factors limiting the availability of noninterfering imaging positions. The robotic US imaging system was deployed in two liver SABR patients during CT simulation with successful acquisition of 4D US sequences in different imaging positions. This study indicates that for VMAT liver SABR, robotic US imaging of a relevant internal target may be possible in 85% of the cases while using treatment plans currently deployed in the clinic. With beam replanning to account for the presence of robotic US guidance, intrafractional US may be an option for 95% of the liver SABR cases.

Evaluation of pharmacy students' knowledge and perceptions of pharmacogenetics before and after a simulation activity.

PubMed

Patel, Radha V; Chudow, Melissa; Vo, Teresa T; Serag-Bolos, Erini S

The purpose of this study was to evaluate students' knowledge and perceptions of the clinical application of pharmacogenetics through a simulation activity and to assess communication of pharmacogenetic-guided treatment recommendations utilizing standardized patients. Third-year students in the four-year doctor of pharmacy (PharmD) program at University of South Florida College of Pharmacy completed a pharmacogenetics simulation involving a patient case review, interpretation of pharmacogenetic test results, completion of a situation, background, assessment, recommendation (SBAR) note with drug therapy recommendations, and patient counseling. Voluntary assessments were completed before and after the simulation, which included demographics, knowledge, and perceptions of students' ability to interpret and communicate pharmacogenetic results. Response rates for the pre- and post-simulation assessments were 109 (98%) and 104 (94%), respectively. Correct responses in application-type questions improved after the simulation (74%) compared to before the simulation (44%, p < 0.01). Responses to perception questions shifted towards "strongly agree" or "agree" after the simulation (p < 0.01). The simulation gave students an opportunity to apply pharmacogenetics knowledge and allowed them to gain an appreciation of pharmacists' roles within the pharmacogenetics field. Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical phenotype-based gene prioritization: an initial study using semantic similarity and the human phenotype ontology.

PubMed

Masino, Aaron J; Dechene, Elizabeth T; Dulik, Matthew C; Wilkens, Alisha; Spinner, Nancy B; Krantz, Ian D; Pennington, Jeffrey W; Robinson, Peter N; White, Peter S

2014-07-21

Exome sequencing is a promising method for diagnosing patients with a complex phenotype. However, variant interpretation relative to patient phenotype can be challenging in some scenarios, particularly clinical assessment of rare complex phenotypes. Each patient's sequence reveals many possibly damaging variants that must be individually assessed to establish clear association with patient phenotype. To assist interpretation, we implemented an algorithm that ranks a given set of genes relative to patient phenotype. The algorithm orders genes by the semantic similarity computed between phenotypic descriptors associated with each gene and those describing the patient. Phenotypic descriptor terms are taken from the Human Phenotype Ontology (HPO) and semantic similarity is derived from each term's information content. Model validation was performed via simulation and with clinical data. We simulated 33 Mendelian diseases with 100 patients per disease. We modeled clinical conditions by adding noise and imprecision, i.e. phenotypic terms unrelated to the disease and terms less specific than the actual disease terms. We ranked the causative gene against all 2488 HPO annotated genes. The median causative gene rank was 1 for the optimal and noise cases, 12 for the imprecision case, and 60 for the imprecision with noise case. Additionally, we examined a clinical cohort of subjects with hearing impairment. The disease gene median rank was 22. However, when also considering the patient's exome data and filtering non-exomic and common variants, the median rank improved to 3. Semantic similarity can rank a causative gene highly within a gene list relative to patient phenotype characteristics, provided that imprecision is mitigated. The clinical case results suggest that phenotype rank combined with variant analysis provides significant improvement over the individual approaches. We expect that this combined prioritization approach may increase accuracy and decrease effort for clinical genetic diagnosis.

Using simulation in out-patient queues: a case study.

PubMed

Huarng, F; Lee, M H

1996-01-01

Overwork and overcrowding in some periods was an important issue for the out-patient department of a local hospital in Chia-Yi in Taiwan. The hospital administrators wanted to manage the patient flow effectively. Describes a study which focused on the utilization of doctors and staff in the out-patient department, the time spent in the hospital by an out-patient, and the length of the out-patient queue. Explains how a computer simulation model was developed to study how changes in the appointment system, staffing policies and service units would affect the observed bottleneck. The results show that the waiting time was greatly reduced and the workload of the doctor was also reduced to a reasonable rate in the overwork and overcrowding periods.

Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT

NASA Astrophysics Data System (ADS)

Angel, Erin; Yaghmai, Nazanin; Matilda Jude, Cecilia; DeMarco, John J.; Cagnon, Christopher H.; Goldin, Jonathan G.; Primak, Andrew N.; Stevens, Donna M.; Cody, Dianna D.; McCollough, Cynthia H.; McNitt-Gray, Michael F.

2009-02-01

Tube current modulation was designed to reduce radiation dose in CT imaging while maintaining overall image quality. This study aims to develop a method for evaluating the effects of tube current modulation (TCM) on organ dose in CT exams of actual patient anatomy. This method was validated by simulating a TCM and a fixed tube current chest CT exam on 30 voxelized patient models and estimating the radiation dose to each patient's glandular breast tissue. This new method for estimating organ dose was compared with other conventional estimates of dose reduction. Thirty detailed voxelized models of patient anatomy were created based on image data from female patients who had previously undergone clinically indicated CT scans including the chest area. As an indicator of patient size, the perimeter of the patient was measured on the image containing at least one nipple using a semi-automated technique. The breasts were contoured on each image set by a radiologist and glandular tissue was semi-automatically segmented from this region. Previously validated Monte Carlo models of two multidetector CT scanners were used, taking into account details about the source spectra, filtration, collimation and geometry of the scanner. TCM data were obtained from each patient's clinical scan and factored into the model to simulate the effects of TCM. For each patient model, two exams were simulated: a fixed tube current chest CT and a tube current modulated chest CT. X-ray photons were transported through the anatomy of the voxelized patient models, and radiation dose was tallied in the glandular breast tissue. The resulting doses from the tube current modulated simulations were compared to the results obtained from simulations performed using a fixed mA value. The average radiation dose to the glandular breast tissue from a fixed tube current scan across all patient models was 19 mGy. The average reduction in breast dose using the tube current modulated scan was 17%. Results were size dependent with smaller patients getting better dose reduction (up to 64% reduction) and larger patients getting a smaller reduction, and in some cases the dose actually increased when using tube current modulation (up to 41% increase). The results indicate that radiation dose to glandular breast tissue generally decreases with the use of tube current modulated CT acquisition, but that patient size (and in some cases patient positioning) may affect dose reduction.

Systematic Review of Patient-Specific Surgical Simulation: Toward Advancing Medical Education.

PubMed

Ryu, Won Hyung A; Dharampal, Navjit; Mostafa, Ahmed E; Sharlin, Ehud; Kopp, Gail; Jacobs, William Bradley; Hurlbert, Robin John; Chan, Sonny; Sutherland, Garnette R

Simulation-based education has been shown to be an effective tool to teach foundational technical skills in various surgical specialties. However, most of the current simulations are limited to generic scenarios and do not allow continuation of the learning curve beyond basic technical skills to prepare for more advanced expertise, such as patient-specific surgical planning. The objective of this study was to evaluate the current medical literature with respect to the utilization and educational value of patient-specific simulations for surgical training. We performed a systematic review of the literature using Pubmed, Embase, and Scopus focusing on themes of simulation, patient-specific, surgical procedure, and education. The study included randomized controlled trials, cohort studies, and case-control studies published between 2005 and 2016. Two independent reviewers (W.H.R. and N.D) conducted the study appraisal, data abstraction, and quality assessment of the studies. The search identified 13 studies that met the inclusion criteria; 7 studies employed computer simulations and 6 studies used 3-dimensional (3D) synthetic models. A number of surgical specialties evaluated patient-specific simulation, including neurosurgery, vascular surgery, orthopedic surgery, and interventional radiology. However, most studies were small in size and primarily aimed at feasibility assessments and early validation. Early evidence has shown feasibility and utility of patient-specific simulation for surgical education. With further development of this technology, simulation-based education may be able to support training of higher-level competencies outside the clinical settingto aid learners in their development of surgical skills. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Quantifying the rambunctious journey of the anesthesia provider's hands during simulated, routine care.

PubMed

Biddle, Chuck; Robinson, Kathryn; Pike, Benjamin; Kammerman, Michael; Gay, Beverly; Verhulst, Brad

2016-08-01

The role of anesthesia providers in dispersing potentially pathogenic material from one patient to another during intraoperative care needs further study. In this study we aimed (1) to quantify the dispersion of a surrogate pathogen from a simulated patient's mouth to the anesthesia workstation during routine anesthetic induction, (2) to test the hypothesis that there would be fewer contamination sites by providers who used a double-gloving technique, and (3) to examine the effectiveness of between-case anesthesia apparatus disinfection. Twenty subjects were randomized to a single pair of gloves group (group 1) or a double-gloved group (group 2) and completed a simulated general anesthesia induction, completing a standardized set of interventions. Dispersion of a surrogate pathogen dye placed in the oral cavity of the simulated patient was tracked by a blinded observer and photography. Standard cleaning of the workstation was performed, and residual dye was quantified. Group performance was plotted using regression analysis and rate of contamination compared using parametric statistics. Group 1 contaminated an average of 16.0 (SEM = 0.89) sites compared with group 2, who contaminated an average of 7.6 (SEM = 0.85). The cart drawers, gas flow dials, medication vials, and ventilator controls were significantly contaminated by group 1, but not by group 2 (P < .05 in all cases). There were similar rates of contamination in both groups for the airway equipment, breathing system, intravenous access ports, and the roll of tape used to secure the endotracheal tube. Once the airway management phase of the induction ended, new site contamination continued at a high rate in group 1 but not group 2. A double-gloving technique was associated with less spread of an oral inoculum to the workstation but was not uniformly protective. Between-case cleaning was ineffective in removing the contaminant, indicating that biologic material from one patient may be present when subsequent patients are cared for. This suggests risks for the current patient (eg, skin or oral site transfer to an intravenous site) and also may place future patients at risk. Importantly, using models that simulate actual clinical events can inform clinical practice and decipher challenging areas of ergonomics. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Endovascular aneurysm repair simulation can lead to decreased fluoroscopy time and accurately delineate the proximal seal zone.

PubMed

Kim, Ann H; Kendrick, Daniel E; Moorehead, Pamela A; Nagavalli, Anil; Miller, Claire P; Liu, Nathaniel T; Wang, John C; Kashyap, Vikram S

2016-07-01

The use of simulators for endovascular aneurysm repair (EVAR) is not widespread. We examined whether simulation could improve procedural variables, including operative time and optimizing proximal seal. For the latter, we compared suprarenal vs infrarenal fixation endografts, right femoral vs left femoral main body access, and increasing angulation of the proximal aortic neck. Computed tomography angiography was obtained from 18 patients who underwent EVAR at a single institution. Patient cases were uploaded to the ANGIO Mentor endovascular simulator (Simbionix, Cleveland, Ohio) allowing for three-dimensional reconstruction and adapted for simulation with suprarenal fixation (Endurant II; Medtronic Inc, Minneapolis, Minn) and infrarenal fixation (C3; W. L. Gore & Associates Inc, Newark, Del) deployment systems. Three EVAR novices and three experienced surgeons performed 18 cases from each side with each device in randomized order (n = 72 simulations/participant). The cases were stratified into three groups according to the degree of infrarenal angulation: 0° to 20°, 21° to 40°, and 41° to 66°. Statistical analysis used paired t-test and one-way analysis of variance. Mean fluoroscopy time for participants decreased by 48.6% (P < .0001), and total procedure time decreased by 33.8% (P < .0001) when initial cases were compared with final cases. When stent deployment accuracy was evaluated across all cases, seal zone coverage in highly angulated aortic necks was significantly decreased. The infrarenal device resulted in mean aortic neck zone coverage of 91.9%, 89.4%, and 75.4% (P < .0001 by one-way analysis of variance), whereas the suprarenal device yielded 92.9%, 88.7%, and 71.5% (P < .0001) for the 0° to 20°, 21° to 40°, and 41° to 66° cases, respectively. Suprarenal fixation did not increase seal zone coverage. The side of femoral access for the main body did not influence proximal seal zone coverage regardless of infrarenal angulation. Simulation of EVAR leads to decreased fluoroscopy times for novice and experienced operators. Side of femoral access did not affect precision of proximal endograft landing. The angulated aortic neck leads to decreased proximal seal zone coverage regardless of infrarenal or suprarenal fixation devices. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Evaluating the Impact of Classroom Education on the Management of Septic Shock Using Human Patient Simulation.

PubMed

Lighthall, Geoffrey K; Bahmani, Dona; Gaba, David

2016-02-01

Classroom lectures are the mainstay of imparting knowledge in a structured manner and have the additional goals of stimulating critical thinking, lifelong learning, and improvements in patient care. The impact of lectures on patient care is difficult to examine in critical care because of the heterogeneity in patient conditions and personnel as well as confounders such as time pressure, interruptions, fatigue, and nonstandardized observation methods. The critical care environment was recreated in a simulation laboratory using a high-fidelity mannequin simulator, where a mannequin simulator with a standardized script for septic shock was presented to trainees. The reproducibility of this patient and associated conditions allowed the evaluation of "clinical performance" in the management of septic shock. In a previous study, we developed and validated tools for the quantitative analysis of house staff managing septic shock simulations. In the present analysis, we examined whether measures of clinical performance were improved in those cases where a lecture on the management of shock preceded a simulated exercise on the management of septic shock. The administration of the septic shock simulations allowed for performance measurements to be calculated for both medical interns and for subsequent management by a larger resident-led team. The analysis revealed that receiving a lecture on shock before managing a simulated patient with septic shock did not produce scores higher than for those who did not receive the previous lecture. This result was similar for both interns managing the patient and for subsequent management by a resident-led team. We failed to find an immediate impact on clinical performance in simulations of septic shock after a lecture on the management of this syndrome. Lectures are likely not a reliable sole method for improving clinical performance in the management of complex disease processes.

An experimental study on the effects of a simulation game on students' clinical cognitive skills and motivation.

PubMed

Dankbaar, Mary E W; Alsma, Jelmer; Jansen, Els E H; van Merrienboer, Jeroen J G; van Saase, Jan L C M; Schuit, Stephanie C E

2016-08-01

Simulation games are becoming increasingly popular in education, but more insight in their critical design features is needed. This study investigated the effects of fidelity of open patient cases in adjunct to an instructional e-module on students' cognitive skills and motivation. We set up a three-group randomized post-test-only design: a control group working on an e-module; a cases group, combining the e-module with low-fidelity text-based patient cases, and a game group, combining the e-module with a high-fidelity simulation game with the same cases. Participants completed questionnaires on cognitive load and motivation. After a 4-week study period, blinded assessors rated students' cognitive emergency care skills in two mannequin-based scenarios. In total 61 students participated and were assessed; 16 control group students, 20 cases students and 25 game students. Learning time was 2 h longer for the cases and game groups than for the control group. Acquired cognitive skills did not differ between groups. The game group experienced higher intrinsic and germane cognitive load than the cases group (p = 0.03 and 0.01) and felt more engaged (p < 0.001). Students did not profit from working on open cases (in adjunct to an e-module), which nonetheless challenged them to study longer. The e-module appeared to be very effective, while the high-fidelity game, although engaging, probably distracted students and impeded learning. Medical educators designing motivating and effective skills training for novices should align case complexity and fidelity with students' proficiency level. The relation between case-fidelity, motivation and skills development is an important field for further study.

A Practical Cone-beam CT Scatter Correction Method with Optimized Monte Carlo Simulations for Image-Guided Radiation Therapy

PubMed Central

Xu, Yuan; Bai, Ti; Yan, Hao; Ouyang, Luo; Pompos, Arnold; Wang, Jing; Zhou, Linghong; Jiang, Steve B.; Jia, Xun

2015-01-01

Cone-beam CT (CBCT) has become the standard image guidance tool for patient setup in image-guided radiation therapy. However, due to its large illumination field, scattered photons severely degrade its image quality. While kernel-based scatter correction methods have been used routinely in the clinic, it is still desirable to develop Monte Carlo (MC) simulation-based methods due to their accuracy. However, the high computational burden of the MC method has prevented routine clinical application. This paper reports our recent development of a practical method of MC-based scatter estimation and removal for CBCT. In contrast with conventional MC approaches that estimate scatter signals using a scatter-contaminated CBCT image, our method used a planning CT image for MC simulation, which has the advantages of accurate image intensity and absence of image truncation. In our method, the planning CT was first rigidly registered with the CBCT. Scatter signals were then estimated via MC simulation. After scatter signals were removed from the raw CBCT projections, a corrected CBCT image was reconstructed. The entire workflow was implemented on a GPU platform for high computational efficiency. Strategies such as projection denoising, CT image downsampling, and interpolation along the angular direction were employed to further enhance the calculation speed. We studied the impact of key parameters in the workflow on the resulting accuracy and efficiency, based on which the optimal parameter values were determined. Our method was evaluated in numerical simulation, phantom, and real patient cases. In the simulation cases, our method reduced mean HU errors from 44 HU to 3 HU and from 78 HU to 9 HU in the full-fan and the half-fan cases, respectively. In both the phantom and the patient cases, image artifacts caused by scatter, such as ring artifacts around the bowtie area, were reduced. With all the techniques employed, we achieved computation time of less than 30 sec including the time for both the scatter estimation and CBCT reconstruction steps. The efficacy of our method and its high computational efficiency make our method attractive for clinical use. PMID:25860299

Hemodynamic simulations in coronary aneurysms of a patient with Kawasaki Disease

NASA Astrophysics Data System (ADS)

Sengupta, Dibyendu; Marsden, Alison; Burns, Jane

2010-11-01

Kawasaki Disease is the leading cause of acquired pediatric heart disease, and can cause large coronary artery aneurysms in untreated cases. A simulation case study has been performed for a 10-year-old male patient with coronary aneurysms. Specialized coronary boundary conditions along with a lumped parameter heart model mimic the interactions between the ventricles and the coronary arteries, achieving physiologic pressure and flow waveforms. Results show persistent low shear stress in the aneurismal regions, and abnormally high shear at the aneurysm neck. Correlation functions have been derived to compare wall shear stress and wall shear stress gradients with recirculation time with the idea of localizing zones of calcification and thrombosis. Results are compared with those of an artificially created normal coronary geometry for the same patient. The long-term goal of this work is to develop links between hemodynamics and thrombotic risk to assist in clinical decision-making.

Cone-beam computed tomography-based diagnosis and treatment simulation for a patient with a protrusive profile and a gummy smile

PubMed Central

Imamura, Toshihiro; Kokai, Satoshi; Ono, Takashi

2018-01-01

For patients with bimaxillary protrusion, significant retraction and intrusion of the anterior teeth are sometimes essential to improve the facial profile. However, severe root resorption of the maxillary incisors occasionally occurs after treatment because of various factors. For instance, it has been reported that approximation or invasion of the incisive canal by the anterior tooth roots during retraction may cause apical root damage. Thus, determination of the position of the maxillary incisors is key for orthodontic diagnosis and treatment planning in such cases. Cone-beam computed tomography (CBCT) may be useful for simulating the post-treatment position of the maxillary incisors and surrounding structures in order to ensure safe teeth movement. Here, we present a case of Class II malocclusion with bimaxillary protrusion, wherein apical root damage due to treatment was minimized by pretreatment evaluation of the anatomical structures and simulation of the maxillary central incisor movement using CBCT. Considerable retraction and intrusion of the maxillary incisors, which resulted in a significant improvement in the facial profile and smile, were achieved without severe root resorption. Our findings suggest that CBCT-based diagnosis and treatment simulation may facilitate safe and dynamic orthodontic tooth movement, particularly in patients requiring maximum anterior tooth retraction. PMID:29732305

The transesophageal echocardiography simulator based on computed tomography images.

PubMed

Piórkowski, Adam; Kempny, Aleksander

2013-02-01

Simulators are a new tool in education in many fields, including medicine, where they greatly improve familiarity with medical procedures, reduce costs, and, importantly, cause no harm to patients. This is so in the case of transesophageal echocardiography (TEE), in which the use of a simulator facilitates spatial orientation and helps in case studies. The aim of the project described in this paper is to simulate an examination by TEE. This research makes use of available computed tomography data to simulate the corresponding echocardiographic view. This paper describes the essential characteristics that distinguish these two modalities and the key principles of the wave phenomena that should be considered in the simulation process, taking into account the conditions specific to the echocardiography. The construction of the CT2TEE (Web-based TEE simulator) is also presented. The considerations include ray-tracing and ray-casting techniques in the context of ultrasound beam and artifact simulation. An important aspect of the interaction with the user is raised.

The Rivalry between Simulation and Problem-Based Learning: A Study of Learning Transfer in Physician Assistant Students

ERIC Educational Resources Information Center

Meyer, Kimberly E.

2010-01-01

The purpose of this dissertation was to evaluate learning transfer achieved by physician assistant students comparing two instructional methods, human patient simulation and electronic clinical case studies. This prospective, randomized, mixed-methods study utilized first and second-year physician assistant student volunteers taking a pretest and…

Computer-assisted virtual preoperative planning in orthopedic surgery for acetabular fractures based on actual computed tomography data.

PubMed

Wang, Guang-Ye; Huang, Wen-Jun; Song, Qi; Qin, Yun-Tian; Liang, Jin-Feng

2016-12-01

Acetabular fractures have always been very challenging for orthopedic surgeons; therefore, appropriate preoperative evaluation and planning are particularly important. This study aimed to explore the application methods and clinical value of preoperative computer simulation (PCS) in treating pelvic and acetabular fractures. Spiral computed tomography (CT) was performed on 13 patients with pelvic and acetabular fractures, and Digital Imaging and Communications in Medicine (DICOM) data were then input into Mimics software to reconstruct three-dimensional (3D) models of actual pelvic and acetabular fractures for preoperative simulative reduction and fixation, and to simulate each surgical procedure. The times needed for virtual surgical modeling and reduction and fixation were also recorded. The average fracture-modeling time was 45 min (30-70 min), and the average time for bone reduction and fixation was 28 min (16-45 min). Among the surgical approaches planned for these 13 patients, 12 were finally adopted; 12 cases used the simulated surgical fixation, and only 1 case used a partial planned fixation method. PCS can provide accurate surgical plans and data support for actual surgeries.

Educating resident physicians using virtual case-based simulation improves diabetes management: a randomized controlled trial.

PubMed

Sperl-Hillen, JoAnn; O'Connor, Patrick J; Ekstrom, Heidi L; Rush, William A; Asche, Stephen E; Fernandes, Omar D; Appana, Deepika; Amundson, Gerald H; Johnson, Paul E; Curran, Debra M

2014-12-01

To test a virtual case-based Simulated Diabetes Education intervention (SimDE) developed to teach primary care residents how to manage diabetes. Nineteen primary care residency programs, with 341 volunteer residents in all postgraduate years (PGY), were randomly assigned to a SimDE intervention group or control group (CG). The Web-based interactive educational intervention used computerized virtual patients who responded to provider actions through programmed simulation models. Eighteen distinct learning cases (L-cases) were assigned to SimDE residents over six months from 2010 to 2011. Impact was assessed using performance on four virtual assessment cases (A-cases), an objective knowledge test, and pre-post changes in self-assessed diabetes knowledge and confidence. Group comparisons were analyzed using generalized linear mixed models, controlling for clustering of residents within residency programs and differences in baseline knowledge. The percentages of residents appropriately achieving A-case composite clinical goals for glucose, blood pressure, and lipids were as follows: A-case 1: SimDE = 21.2%, CG = 1.8%, P = .002; A-case 2: SimDE = 15.7%, CG = 4.7%, P = .02; A-case 3: SimDE = 48.0%, CG = 10.4%, P < .001; and A-case 4: SimDE = 42.1%, CG = 18.7%, P = .004. The mean knowledge score and pre-post changes in self-assessed knowledge and confidence were significantly better for SimDE group than CG participants. A virtual case-based simulated diabetes education intervention improved diabetes management skills, knowledge, and confidence for primary care residents.

Assessing potentially dangerous medical actions with the computer-based case simulation portion of the USMLE step 3 examination.

PubMed

Harik, Polina; Cuddy, Monica M; O'Donovan, Seosaimhin; Murray, Constance T; Swanson, David B; Clauser, Brian E

2009-10-01

The 2000 Institute of Medicine report on patient safety brought renewed attention to the issue of preventable medical errors, and subsequently specialty boards and the National Board of Medical Examiners were encouraged to play a role in setting expectations around safety education. This paper examines potentially dangerous actions taken by examinees during the portion of the United States Medical Licensing Examination Step 3 that is particularly well suited to evaluating lapses in physician decision making, the Computer-based Case Simulation (CCS). Descriptive statistics and a general linear modeling approach were used to analyze dangerous actions ordered by 25,283 examinees that completed CCS for the first time between November 2006 and January 2008. More than 20% of examinees ordered at least one dangerous action with the potential to cause significant patient harm. The propensity to order dangerous actions may vary across clinical cases. The CCS format may provide a means of collecting important information about patient-care situations in which examinees may be more likely to commit dangerous actions and the propensity of examinees to order dangerous tests and treatments.

Patient-specific coronary artery blood flow simulation using myocardial volume partitioning

NASA Astrophysics Data System (ADS)

Kim, Kyung Hwan; Kang, Dongwoo; Kang, Nahyup; Kim, Ji-Yeon; Lee, Hyong-Euk; Kim, James D. K.

2013-03-01

Using computational simulation, we can analyze cardiovascular disease in non-invasive and quantitative manners. More specifically, computational modeling and simulation technology has enabled us to analyze functional aspect such as blood flow, as well as anatomical aspect such as stenosis, from medical images without invasive measurements. Note that the simplest ways to perform blood flow simulation is to apply patient-specific coronary anatomy with other average-valued properties; in this case, however, such conditions cannot fully reflect accurate physiological properties of patients. To resolve this limitation, we present a new patient-specific coronary blood flow simulation method by myocardial volume partitioning considering artery/myocardium structural correspondence. We focus on that blood supply is closely related to the mass of each myocardial segment corresponding to the artery. Therefore, we applied this concept for setting-up simulation conditions in the way to consider many patient-specific features as possible from medical image: First, we segmented coronary arteries and myocardium separately from cardiac CT; then the myocardium is partitioned into multiple regions based on coronary vasculature. The myocardial mass and required blood mass for each artery are estimated by converting myocardial volume fraction. Finally, the required blood mass is used as boundary conditions for each artery outlet, with given average aortic blood flow rate and pressure. To show effectiveness of the proposed method, fractional flow reserve (FFR) by simulation using CT image has been compared with invasive FFR measurement of real patient data, and as a result, 77% of accuracy has been obtained.

Assessment of Robotic Patient Simulators for Training in Manual Physical Therapy Examination Techniques

PubMed Central

Ishikawa, Shun; Okamoto, Shogo; Isogai, Kaoru; Akiyama, Yasuhiro; Yanagihara, Naomi; Yamada, Yoji

2015-01-01

Robots that simulate patients suffering from joint resistance caused by biomechanical and neural impairments are used to aid the training of physical therapists in manual examination techniques. However, there are few methods for assessing such robots. This article proposes two types of assessment measures based on typical judgments of clinicians. One of the measures involves the evaluation of how well the simulator presents different severities of a specified disease. Experienced clinicians were requested to rate the simulated symptoms in terms of severity, and the consistency of their ratings was used as a performance measure. The other measure involves the evaluation of how well the simulator presents different types of symptoms. In this case, the clinicians were requested to classify the simulated resistances in terms of symptom type, and the average ratios of their answers were used as performance measures. For both types of assessment measures, a higher index implied higher agreement among the experienced clinicians that subjectively assessed the symptoms based on typical symptom features. We applied these two assessment methods to a patient knee robot and achieved positive appraisals. The assessment measures have potential for use in comparing several patient simulators for training physical therapists, rather than as absolute indices for developing a standard. PMID:25923719

Reliability and Validity in Hospital Case-Mix Measurement

PubMed Central

Pettengill, Julian; Vertrees, James

1982-01-01

There is widespread interest in the development of a measure of hospital output. This paper describes the problem of measuring the expected cost of the mix of inpatient cases treated in a hospital (hospital case-mix) and a general approach to its solution. The solution is based on a set of homogenous groups of patients, defined by a patient classification system, and a set of estimated relative cost weights corresponding to the patient categories. This approach is applied to develop a summary measure of the expected relative costliness of the mix of Medicare patients treated in 5,576 participating hospitals. The Medicare case-mix index is evaluated by estimating a hospital average cost function. This provides a direct test of the hypothesis that the relationship between Medicare case-mix and Medicare cost per case is proportional. The cost function analysis also provides a means of simulating the effects of classification error on our estimate of this relationship. Our results indicate that this general approach to measuring hospital case-mix provides a valid and robust measure of the expected cost of a hospital's case-mix. PMID:10309909

Embedding patient simulation in a pediatric cardiology rotation: a unique opportunity for improving resident education.

PubMed

Mohan, Shaun; Follansbee, Christopher; Nwankwo, Ugonna; Hofkosh, Dena; Sherman, Frederick S; Hamilton, Melinda F

2015-01-01

High-fidelity patient simulation (HFPS) has been used in medical education to bridge gaps in medical knowledge and clinical skills. Few studies have analyzed the impact of HFPS in subspecialty rotations for pediatric residents. We hypothesized that pediatric residents exposed to HFPS with a structured content curriculum would perform better on a case quiz than residents without exposure to HFPS. Prospective randomized controlled Tertiary-care free standing children's hospital During a cardiology rotation, senior pediatric residents completed an online pediatric cardiology curriculum and a cardiology quiz. After randomization into two groups, the study group participated in a fully debriefed HFPS session. The control group had no HFPS. Both groups completed a case quiz. Confidence surveys pre- and postsimulation were completed. From October 2010 through March 2013, 55 residents who rotated through the pediatric cardiology rotation were used in the final analysis (30 control, 25 in the study group). There was no significant difference between groups on the initial cardiology quiz. The study group scored higher on the case quiz compared with the control group (P = .024). Based on pre- and postsimulation questionnaires, residents' confidence in approaching a pediatric cardiology patient improved from an average Likert score of 5.1 to 7.5 (on scale of 0-10) (P < .001). Incorporation of HFPS into a preexisting pediatric cardiology rotation was feasible and well received. Our study suggests that simulation promotes increased confidence and may modestly improve clinical reasoning compared to traditional educational techniques. Targeted simulation sessions may readily be incorporated into pediatric subspecialty rotations. © 2014 Wiley Periodicals, Inc.

Standardisation of role players for the Clinical Skills Assessment of the MRCGP.

PubMed

Russell, David; Simpson, Robin; Rendel, Sue

2011-05-01

This paper describes the processes used to prepare the role players who simulate the 'patients' in the MRCGP Clinical Skills Assessment (CSA) examination, one of the licensing qualifications for GPs completing their training. Because it is such a high-stakes exam, the CSA must be seen to be fair and trustworthy, and such attributes could be compromised by inadequate role player performance. On a CSA examination day, three role players simulate the same 'patient' simultaneously on three different exam floors, each playing the same case up to 26 times on the day, and these 'patients' must present in a consistent and reliable manner to ensure that all candidates face the same test situation. The paper describes the initial selection and training of the actors, how they are prepared on the day of the exam itself, and the quality assurance processes designed to ensure that the exam has excellent role players performing as the simulated 'patients'.

Comparing Real-time Versus Delayed Video Assessments for Evaluating ACGME Sub-competency Milestones in Simulated Patient Care Environments

PubMed Central

Stiegler, Marjorie; Hobbs, Gene; Martinelli, Susan M; Zvara, David; Arora, Harendra; Chen, Fei

2018-01-01

Background Simulation is an effective method for creating objective summative assessments of resident trainees. Real-time assessment (RTA) in simulated patient care environments is logistically challenging, especially when evaluating a large group of residents in multiple simulation scenarios. To date, there is very little data comparing RTA with delayed (hours, days, or weeks later) video-based assessment (DA) for simulation-based assessments of Accreditation Council for Graduate Medical Education (ACGME) sub-competency milestones. We hypothesized that sub-competency milestone evaluation scores obtained from DA, via audio-video recordings, are equivalent to the scores obtained from RTA. Methods Forty-one anesthesiology residents were evaluated in three separate simulated scenarios, representing different ACGME sub-competency milestones. All scenarios had one faculty member perform RTA and two additional faculty members perform DA. Subsequently, the scores generated by RTA were compared with the average scores generated by DA. Variance component analysis was conducted to assess the amount of variation in scores attributable to residents and raters. Results Paired t-tests showed no significant difference in scores between RTA and averaged DA for all cases. Cases 1, 2, and 3 showed an intraclass correlation coefficient (ICC) of 0.67, 0.85, and 0.50 for agreement between RTA scores and averaged DA scores, respectively. Analysis of variance of the scores assigned by the three raters showed a small proportion of variance attributable to raters (4% to 15%). Conclusions The results demonstrate that video-based delayed assessment is as reliable as real-time assessment, as both assessment methods yielded comparable scores. Based on a department’s needs or logistical constraints, our findings support the use of either real-time or delayed video evaluation for assessing milestones in a simulated patient care environment. PMID:29736352

Cerebral Aneurysm Clipping Surgery Simulation Using Patient-Specific 3D Printing and Silicone Casting.

PubMed

Ryan, Justin R; Almefty, Kaith K; Nakaji, Peter; Frakes, David H

2016-04-01

Neurosurgery simulator development is growing as practitioners recognize the need for improved instructional and rehearsal platforms to improve procedural skills and patient care. In addition, changes in practice patterns have decreased the volume of specific cases, such as aneurysm clippings, which reduces the opportunity for operating room experience. The authors developed a hands-on, dimensionally accurate model for aneurysm clipping using patient-derived anatomic data and three-dimensional (3D) printing. Design of the model focused on reproducibility as well as adaptability to new patient geometry. A modular, reproducible, and patient-derived medical simulacrum was developed for medical learners to practice aneurysmal clipping procedures. Various forms of 3D printing were used to develop a geometrically accurate cranium and vascular tree featuring 9 patient-derived aneurysms. 3D printing in conjunction with elastomeric casting was leveraged to achieve a patient-derived brain model with tactile properties not yet available from commercial 3D printing technology. An educational pilot study was performed to gauge simulation efficacy. Through the novel manufacturing process, a patient-derived simulacrum was developed for neurovascular surgical simulation. A follow-up qualitative study suggests potential to enhance current educational programs; assessments support the efficacy of the simulacrum. The proposed aneurysm clipping simulator has the potential to improve learning experiences in surgical environment. 3D printing and elastomeric casting can produce patient-derived models for a dynamic learning environment that add value to surgical training and preparation. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of 3D Echocardiogram-Derived 3D Printed Valve Models to Molded Models for Simulated Repair of Pediatric Atrioventricular Valves.

PubMed

Scanlan, Adam B; Nguyen, Alex V; Ilina, Anna; Lasso, Andras; Cripe, Linnea; Jegatheeswaran, Anusha; Silvestro, Elizabeth; McGowan, Francis X; Mascio, Christopher E; Fuller, Stephanie; Spray, Thomas L; Cohen, Meryl S; Fichtinger, Gabor; Jolley, Matthew A

2018-03-01

Mastering the technical skills required to perform pediatric cardiac valve surgery is challenging in part due to limited opportunity for practice. Transformation of 3D echocardiographic (echo) images of congenitally abnormal heart valves to realistic physical models could allow patient-specific simulation of surgical valve repair. We compared materials, processes, and costs for 3D printing and molding of patient-specific models for visualization and surgical simulation of congenitally abnormal heart valves. Pediatric atrioventricular valves (mitral, tricuspid, and common atrioventricular valve) were modeled from transthoracic 3D echo images using semi-automated methods implemented as custom modules in 3D Slicer. Valve models were then both 3D printed in soft materials and molded in silicone using 3D printed "negative" molds. Using pre-defined assessment criteria, valve models were evaluated by congenital cardiac surgeons to determine suitability for simulation. Surgeon assessment indicated that the molded valves had superior material properties for the purposes of simulation compared to directly printed valves (p < 0.01). Patient-specific, 3D echo-derived molded valves are a step toward realistic simulation of complex valve repairs but require more time and labor to create than directly printed models. Patient-specific simulation of valve repair in children using such models may be useful for surgical training and simulation of complex congenital cases.

Virtual Cerebral Aneurysm Clipping with Real-Time Haptic Force Feedback in Neurosurgical Education.

PubMed

Gmeiner, Matthias; Dirnberger, Johannes; Fenz, Wolfgang; Gollwitzer, Maria; Wurm, Gabriele; Trenkler, Johannes; Gruber, Andreas

2018-04-01

Realistic, safe, and efficient modalities for simulation-based training are highly warranted to enhance the quality of surgical education, and they should be incorporated in resident training. The aim of this study was to develop a patient-specific virtual cerebral aneurysm-clipping simulator with haptic force feedback and real-time deformation of the aneurysm and vessels. A prototype simulator was developed from 2012 to 2016. Evaluation of virtual clipping by blood flow simulation was integrated in this software, and the prototype was evaluated by 18 neurosurgeons. In 4 patients with different medial cerebral artery aneurysms, virtual clipping was performed after real-life surgery, and surgical results were compared regarding clip application, surgical trajectory, and blood flow. After head positioning and craniotomy, bimanual virtual aneurysm clipping with an original forceps was performed. Blood flow simulation demonstrated residual aneurysm filling or branch stenosis. The simulator improved anatomic understanding for 89% of neurosurgeons. Simulation of head positioning and craniotomy was considered realistic by 89% and 94% of users, respectively. Most participants agreed that this simulator should be integrated into neurosurgical education (94%). Our illustrative cases demonstrated that virtual aneurysm surgery was possible using the same trajectory as in real-life cases. Both virtual clipping and blood flow simulation were realistic in broad-based but not calcified aneurysms. Virtual clipping of a calcified aneurysm could be performed using the same surgical trajectory, but not the same clip type. We have successfully developed a virtual aneurysm-clipping simulator. Next, we will prospectively evaluate this device for surgical procedure planning and education. Copyright © 2018 Elsevier Inc. All rights reserved.

Optimizing Treatment of Lung Cancer Patients with Comorbidities

DTIC Science & Technology

2017-10-01

of treatment options, comorbid illness, age, sex , histology, and tumor size. We will simulate base case scenarios for stage I NSCLC for all possible...fitting adjusted logistic regression models controlling for age, sex and cancer stage. Results Overall, 5,644 (80.4%) and 1,377 (19.6%) patients

The Relationship of Endoscopic Proficiency to Educational Expense for Virtual Reality Simulator Training Amongst Surgical Trainees.

PubMed

Raque, Jessica; Goble, Adam; Jones, Veronica M; Waldman, Lindsey E; Sutton, Erica

2015-07-01

With the introduction of Fundamentals of Endoscopic Surgery, training methods in flexible endoscopy are being augmented with simulation-based curricula. The investment for virtual reality simulators warrants further research into its training advantage. Trainees were randomized into bedside or simulator training groups (BED vs SIM). SIM participated in a proficiency-based virtual reality curriculum. Trainees' endoscopic skills were rated using the Global Assessment of Gastrointestinal Endoscopic Skills (GAGES) in the patient care setting. The number of cases to reach 90 per cent of the maximum GAGES score and calculated costs of training were compared. Nineteen residents participated in the study. There was no difference in the average number of cases required to achieve 90 per cent of the maximum GAGES score for esophagogastroduodenoscopy, 13 (SIM) versus11 (BED) (P = 0.63), or colonoscopy 21 (SIM) versus 4 (BED) (P = 0.34). The average per case cost of training for esophagogastroduodenoscopy was $35.98 (SIM) versus $39.71 (BED) (P = 0.50), not including the depreciation costs associated with the simulator ($715.00 per resident over six years). Use of a simulator appeared to increase the cost of training without accelerating the learning curve or decreasing faculty time spent in instruction. The importance of simulation in endoscopy training will be predicated on more cost-effective simulators.

Teaching Old Dogs New Tricks: Using Cognitive Feedback to Improve Physicians' Diagnostic Judgments on Simulated Cases.

ERIC Educational Resources Information Center

Wigton, Robert S.; And Others

1990-01-01

An educational intervention was effective in improving the judgment of experienced student-health physicians (N=11) in predicting positive culture in simulated patients with pharyngitis. The intervention was three parts: an initial one-hour lecture; three sessions with computer-based cognitive feedback; and monthly reports of the percentage of…

Hypogammaglobulinemia factitia- Munchausen syndrome masquerading as common variable immune deficiency

PubMed Central

2013-01-01

Background We describe the first case of a patient with factitious disorder who closely simulated a primary immune deficiency disorder – Common Variable Immune Deficiency (CVID), by surreptitiously ingesting non-steroidal anti-inflammatory agents. Case description He was treated with several expensive and potentially dangerous drugs before the diagnosis was established through collateral information. In retrospect he did not meet the proposed new criteria for CVID. These criteria may prove useful in distinguishing cases of CVID from secondary hypogammaglobulinemia. Conclusion It is imperative clinicians recognise patients with factitious disorder at the earliest opportunity to prevent iatrogenic morbidity and mortality. PMID:24341706

Using in situ simulation to identify and resolve latent environmental threats to patient safety: case study involving operational changes in a labor and delivery ward.

PubMed

Hamman, William R; Beaudin-Seiler, Beth M; Beaubien, Jeffrey M; Gullickson, Amy M; Orizondo-Korotko, Krystyna; Gross, Amy C; Fuqua, Wayne; Lammers, Richard

2010-01-01

Since the publication of "To Err Is Human" in 1999, health care professionals have looked to high-reliability industries such as aviation for guidance on improving system safety. One of the most widely adopted aviation-derived approaches is simulation-based team training, also known as crew resource management training. In the health care domain, crew resource management training often takes place in custom-built simulation laboratories that are designed to replicate operating rooms or labor and delivery rooms. Unlike these traditional crew resource management training programs, "in situ simulation" occurs on actual patient care units, involves actual health care team members, and uses actual organization processes to train and assess team performance. During the past 24 months, our research team has conducted nearly 40 in situ simulations. In this article, we present the results from 1 such simulation: a patient who experienced a difficult labor that resulted in an emergency caesarian section and hysterectomy. During the simulation, a number of latent environmental threats to safety were identified. This article presents the latent threats and the steps that the hospital has taken to remedy them.

Design, development, and evaluation of an online virtual emergency department for training trauma teams.

PubMed

Youngblood, Patricia; Harter, Phillip M; Srivastava, Sakti; Moffett, Shannon; Heinrichs, Wm LeRoy; Dev, Parvati

2008-01-01

Training interdisciplinary trauma teams to work effectively together using simulation technology has led to a reduction in medical errors in emergency department, operating room, and delivery room contexts. High-fidelity patient simulators (PSs)-the predominant method for training healthcare teams-are expensive to develop and implement and require that trainees be present in the same place at the same time. In contrast, online computer-based simulators are more cost effective and allow simultaneous participation by students in different locations and time zones. In this pilot study, the researchers created an online virtual emergency department (Virtual ED) for team training in crisis management, and compared the effectiveness of the Virtual ED with the PS. We hypothesized that there would be no difference in learning outcomes for graduating medical students trained with each method. In this pilot study, we used a pretest-posttest control group, experimental design in which 30 subjects were randomly assigned to either the Virtual ED or the PS system. In the Virtual ED each subject logged into the online environment and took the role of a team member. Four-person teams worked together in the Virtual ED, communicating in real time with live voice over Internet protocol, to manage computer-controlled patients who exhibited signs and symptoms of physical trauma. Each subject had the opportunity to be the team leader. The subjects' leadership behavior as demonstrated in both a pretest case and a posttest case was assessed by 3 raters, using a behaviorally anchored scale. In the PS environment, 4-person teams followed the same research protocol, using the same clinical scenarios in a Simulation Center. Guided by the Emergency Medicine Crisis Resource Management curriculum, both the Virtual ED and the PS groups applied the basic principles of team leadership and trauma management (Advanced Trauma Life Support) to manage 6 trauma cases-a pretest case, 4 training cases, and a posttest case. The subjects in each group were assessed individually with the same simulation method that they used for the training cases. Subjects who used either the Virtual ED or the PS showed significant improvement in performance between pretest and posttest cases (P < 0.05). In addition, there was no significant difference in subjects' performance between the 2 types of simulation, suggesting that the online Virtual ED may be as effective for learning team skills as the PS, the method widely used in Simulation Centers. Data on usability and attitudes toward both simulation methods as learning tools were equally positive. This study shows the potential value of using virtual learning environments for developing medical students' and resident physicians' team leadership and crisis management skills.

Virtual reality case-specific rehearsal in temporal bone surgery: a preliminary evaluation.

PubMed

Arora, Asit; Swords, Chloe; Khemani, Sam; Awad, Zaid; Darzi, Ara; Singh, Arvind; Tolley, Neil

2014-01-01

1. To investigate the feasibility of performing case-specific surgical rehearsal using a virtual reality temporal bone simulator. 2. To identify potential clinical applications in temporal bone surgery. Prospective assessment study. St Mary's Hospital, Imperial College NHS Trust, London UK. Sixteen participants consisting of a trainer and trainee group. Twenty-four cadaver temporal bones were CT-scanned and uploaded onto the Voxelman simulator. Sixteen participants performed a 90-min temporal bone dissection on the generic simulation model followed by 3 dissection tasks on the case simulation and cadaver models. Case rehearsal was assessed for feasibility. Clinical applications and usefulness were evaluated using a 5-point Likert-type scale. The upload process required a semi-automated system. Average time for upload was 20 min. Suboptimal reconstruction occurred in 21% of cases arising when the mastoid process and ossicular chain were not captured (n = 2) or when artefact was generated (n = 3). Case rehearsal rated highly (Likert score >4) for confidence (75%), facilitating planning (75%) and training (94%). Potential clinical applications for case rehearsal include ossicular chain surgery, cochlear implantation and congenital anomalies. Case rehearsal of cholesteatoma surgery is not possible on the current platform due to suboptimal soft tissue representation. The process of uploading CT data onto a virtual reality temporal bone simulator to perform surgical rehearsal is feasible using a semi-automated system. Further clinical evaluation is warranted to assess the benefit of performing patient-specific surgical rehearsal in selected procedures. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Preoperative planning with three-dimensional reconstruction of patient's anatomy, rapid prototyping and simulation for endoscopic mitral valve repair.

PubMed

Sardari Nia, Peyman; Heuts, Samuel; Daemen, Jean; Luyten, Peter; Vainer, Jindrich; Hoorntje, Jan; Cheriex, Emile; Maessen, Jos

2017-02-01

Mitral valve repair performed by an experienced surgeon is superior to mitral valve replacement for degenerative mitral valve disease; however, many surgeons are still deterred from adapting this procedure because of a steep learning curve. Simulation-based training and planning could improve the surgical performance and reduce the learning curve. The aim of this study was to develop a patient-specific simulation for mitral valve repair and provide a proof of concept of personalized medicine in a patient prospectively planned for mitral valve surgery. A 65-year old male with severe symptomatic mitral valve regurgitation was referred to our mitral valve heart team. On the basis of three-dimensional (3D) transoesophageal echocardiography and computed tomography, 3D reconstructions of the patient's anatomy were constructed. By navigating through these reconstructions, the repair options and surgical access were chosen (minimally invasive repair). Using rapid prototyping and negative mould fabrication, we developed a process to cast a patient-specific mitral valve silicone replica for preoperative repair in a high-fidelity simulator. Mitral valve and negative mould were printed in systole to capture the pathology when the valve closes. A patient-specific mitral valve silicone replica was casted and mounted in the simulator. All repair techniques could be performed in the simulator to choose the best repair strategy. As the valve was printed in systole, no special testing other than adjusting the coaptation area was required. Subsequently, the patient was operated, mitral valve pathology was validated and repair was successfully done as in the simulation. The patient-specific simulation and planning could be applied for surgical training, starting the (minimally invasive) mitral valve repair programme, planning of complex cases and the evaluation of new interventional techniques. The personalized medicine could be a possible pathway towards enhancing reproducibility, patient's safety and effectiveness of a complex surgical procedure. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

"Just-In-Time" Simulation Training Using 3-D Printed Cardiac Models After Congenital Cardiac Surgery.

PubMed

Olivieri, Laura J; Su, Lillian; Hynes, Conor F; Krieger, Axel; Alfares, Fahad A; Ramakrishnan, Karthik; Zurakowski, David; Marshall, M Blair; Kim, Peter C W; Jonas, Richard A; Nath, Dilip S

2016-03-01

High-fidelity simulation using patient-specific three-dimensional (3D) models may be effective in facilitating pediatric cardiac intensive care unit (PCICU) provider training for clinical management of congenital cardiac surgery patients. The 3D-printed heart models were rendered from preoperative cross-sectional cardiac imaging for 10 patients undergoing congenital cardiac surgery. Immediately following surgical repair, a congenital cardiac surgeon and an intensive care physician conducted a simulation training session regarding postoperative care utilizing the patient-specific 3D model for the PCICU team. After the simulation, Likert-type 0 to 10 scale questionnaire assessed participant perception of impact of the training session. Seventy clinicians participated in training sessions, including 22 physicians, 38 nurses, and 10 ancillary care providers. Average response to whether 3D models were more helpful than standard hand off was 8.4 of 10. Questions regarding enhancement of understanding and clinical ability received average responses of 9.0 or greater, and 90% of participants scored 8 of 10 or higher. Nurses scored significantly higher than other clinicians on self-reported familiarity with the surgery (7.1 vs. 5.8; P = .04), clinical management ability (8.6 vs. 7.7; P = .02), and ability enhancement (9.5 vs. 8.7; P = .02). Compared to physicians, nurses and ancillary providers were more likely to consider 3D models more helpful than standard hand off (8.7 vs. 7.7; P = .05). Higher case complexity predicted greater enhancement of understanding of surgery (P = .04). The 3D heart models can be used to enhance congenital cardiac critical care via simulation training of multidisciplinary intensive care teams. Benefit may be dependent on provider type and case complexity. © The Author(s) 2016.

Improving Patient Safety with X-Ray and Anesthesia Machine Ventilator Synchronization: A Medical Device Interoperability Case Study

NASA Astrophysics Data System (ADS)

Arney, David; Goldman, Julian M.; Whitehead, Susan F.; Lee, Insup

When a x-ray image is needed during surgery, clinicians may stop the anesthesia machine ventilator while the exposure is made. If the ventilator is not restarted promptly, the patient may experience severe complications. This paper explores the interconnection of a ventilator and simulated x-ray into a prototype plug-and-play medical device system. This work assists ongoing interoperability framework development standards efforts to develop functional and non-functional requirements and illustrates the potential patient safety benefits of interoperable medical device systems by implementing a solution to a clinical use case requiring interoperability.

Utilization of a virtual patient for advanced assessment of student performance in pain management.

PubMed

Smith, Michael A; Waite, Laura H

2017-09-01

To assess student performance and achievement of course objectives following the integration of a virtual patient case designed to promote active, patient-centered learning in a required pharmacy course. DecisionSim™ (Kynectiv, Inc., Chadsford, PA), a dynamic virtual patient platform, was used to implement an interactive patient case to augment pain management material presented during a didactic session in a pharmacotherapy course. Simulation performance data were collected and analyzed. Student exam performance on pain management questions was compared to student exam performance on nearly identical questions from a prior year when a paper-based case was used instead of virtual patient technology. Students who performed well on the virtual patient case performed better on exam questions related to patient assessment (p = 0.0244), primary pharmacological therapy (p = 0.0001), and additional pharmacological therapy (p = 0.0001). Overall exam performance did not differ between the two groups. However, students with exposure to the virtual patient case demonstrated significantly better performance on higher level Bloom's Taxonomy questions that required them to create pharmacotherapy regimens (p=0.0005). Students in the previous year (exposed only to a paper patient case) performed better in calculating conversions of opioids for patients (p = 0.0001). Virtual patient technology may enhance student performance on high-level Bloom's Taxonomy examination questions. This study adds to the current literature demonstrating the value of virtual patient technology as an active-learning strategy. Copyright © 2017 Elsevier Inc. All rights reserved.

Feasibility of scenario-based simulation training versus traditional workshops in continuing medical education: a randomized controlled trial.

PubMed

Kerr, Brendan; Hawkins, Trisha Lee-Ann; Herman, Robert; Barnes, Sue; Kaufmann, Stephanie; Fraser, Kristin; Ma, Irene W Y

2013-07-18

Although simulation-based training is increasingly used for medical education, its benefits in continuing medical education (CME) are less established. This study seeks to evaluate the feasibility of incorporating simulation-based training into a CME conference and compare its effectiveness with the traditional workshop in improving knowledge and self-reported confidence. Participants (N=27) were group randomized to either a simulation-based workshop or a traditional case-based workshop. Post-training, knowledge assessment score neither did increase significantly in the traditional group (d=0.13; p=0.76) nor did significantly decrease in the simulation group (d= - 0.44; p=0.19). Self-reported comfort in patient assessment parameters increased in both groups (p<0.05 in all). However, only the simulation group reported an increase in comfort in patient management (d=1.1, p=0.051 for the traditional group and d=1.3; p= 0.0003 for the simulation group). At 1 month, comfort measures in the traditional group increased consistently over time while these measures in the simulation group increased post-workshop but decreased by 1 month, suggesting that some of the effects of training with simulation may be short lived. The use of simulation-based training was not associated with benefits in knowledge acquisition, knowledge retention, or comfort in patient assessment. It was associated with superior outcomes in comfort in patient management, but this benefit may be short-lived. Further studies are required to better define the conditions under which simulation-based training is beneficial.

Feasibility of scenario-based simulation training versus traditional workshops in continuing medical education: a randomized controlled trial

PubMed Central

Kerr, Brendan; Hawkins, Trisha Lee-Ann; Herman, Robert; Barnes, Sue; Kaufmann, Stephanie; Fraser, Kristin; Ma, Irene W. Y.

2013-01-01

Introduction Although simulation-based training is increasingly used for medical education, its benefits in continuing medical education (CME) are less established. This study seeks to evaluate the feasibility of incorporating simulation-based training into a CME conference and compare its effectiveness with the traditional workshop in improving knowledge and self-reported confidence. Methods Participants (N=27) were group randomized to either a simulation-based workshop or a traditional case-based workshop. Results Post-training, knowledge assessment score neither did increase significantly in the traditional group (d=0.13; p=0.76) nor did significantly decrease in the simulation group (d= − 0.44; p=0.19). Self-reported comfort in patient assessment parameters increased in both groups (p<0.05 in all). However, only the simulation group reported an increase in comfort in patient management (d=1.1, p=0.051 for the traditional group and d=1.3; p= 0.0003 for the simulation group). At 1 month, comfort measures in the traditional group increased consistently over time while these measures in the simulation group increased post-workshop but decreased by 1 month, suggesting that some of the effects of training with simulation may be short lived. Discussion The use of simulation-based training was not associated with benefits in knowledge acquisition, knowledge retention, or comfort in patient assessment. It was associated with superior outcomes in comfort in patient management, but this benefit may be short-lived. Further studies are required to better define the conditions under which simulation-based training is beneficial. PMID:23870304

Feasibility of scenario-based simulation training versus traditional workshops in continuing medical education: a randomized controlled trial.

PubMed

Kerr, Brendan; Lee-Ann Hawkins, Trisha; Herman, Robert; Barnes, Sue; Kaufmann, Stephanie; Fraser, Kristin; Ma, Irene W Y

2013-01-01

Introduction Although simulation-based training is increasingly used for medical education, its benefits in continuing medical education (CME) are less established. This study seeks to evaluate the feasibility of incorporating simulation-based training into a CME conference and compare its effectiveness with the traditional workshop in improving knowledge and self-reported confidence. Methods Participants (N=27) were group randomized to either a simulation-based workshop or a traditional case-based workshop. Results Post-training, knowledge assessment score neither did increase significantly in the traditional group (d=0.13; p=0.76) nor did significantly decrease in the simulation group (d= - 0.44; p=0.19). Self-reported comfort in patient assessment parameters increased in both groups (p<0.05 in all). However, only the simulation group reported an increase in comfort in patient management (d=1.1, p=0.051 for the traditional group and d=1.3; p= 0.0003 for the simulation group). At 1 month, comfort measures in the traditional group increased consistently over time while these measures in the simulation group increased post-workshop but decreased by 1 month, suggesting that some of the effects of training with simulation may be short lived. Discussion The use of simulation-based training was not associated with benefits in knowledge acquisition, knowledge retention, or comfort in patient assessment. It was associated with superior outcomes in comfort in patient management, but this benefit may be short-lived. Further studies are required to better define the conditions under which simulation-based training is beneficial.

Clinical Spectrum of Autoerythrocyte Sensitization Syndrome: A Series of Five Cases

PubMed Central

Thokchom, Nandakishore Singh; Pradeepa, D.; Hafi, N. A. Bishurul; Verma, Kapila

2018-01-01

Autoerythrocyte sensitization syndrome (Gardner Diamond syndrome or GDS) is a rare syndrome characterized by painful and spontaneous purpura commonly affecting adult women, and is mostly associated with psychiatric illness. Diagnosis is mainly based on clinical presentation, exclusion of other simulating diseases, and psychiatric evaluation. Only few cases have been reported till date. We report five cases of spontaneous purpura with a normal investigation profile, except for iron deficiency anemia in 1 patient, of which three had associated underlying psychiatric illness. Autoerythrocyte sensitization test was positive in all our cases. Patients presenting with painful bruises without significant medical history such as underlying bleeding disorder or drug history or history of trauma should be considered for autoerythrocyte sensitization syndrome, and managed accordingly. The present study is a case series of patients with characteristic features of autoerythrocyte sensitization syndrome, considering the rarity of the reports on its clinical spectra. PMID:29644197

SU-E-I-88: Realistic Pathological Simulations of the NCAT and Zubal Anthropomorphic Models, Based on Clinical PET/CT Data.

PubMed

Papadimitroulas, P; Loudos, G; Le Maitre, A; Efthimiou, N; Visvikis, D; Nikiforidis, G; Kagadis, G C

2012-06-01

In the present study a patient-specific dataset of realistic PET simulations was created, taking into account the variability of clinical oncology data. Tumor variability was tested in the simulated results. A comparison of the produced simulated data was performed to clinical PET/CT data, for the validation and the evaluation of the procedure. Clinical PET/CT data of oncology patients were used as the basis of the simulated variability inserting patient-specific characteristics in the NCAT and the Zubal anthropomorphic phantoms. GATE Monte Carlo toolkit was used for simulating a commercial PET scanner. The standard computational anthropomorphic phantoms were adapted to the CT data (organ shapes), using a fitting algorithm. The activity map was derived from PET images. Patient tumors were segmented and inserted in the phantom, using different activity distributions. The produced simulated data were reconstructed using the STIR opensource software and compared to the original clinical ones. The accuracy of the procedure was tested in four different oncology cases. Each pathological situation was illustrated simulating a) a healthy body, b) insertion of the clinical tumor with homogenous activity, and c) insertion of the clinical tumor with variable activity (voxel-by-voxel) based on the clinical PET data. The accuracy of the presented dataset was compared to the original PET/CT data. Partial Volume Correction (PVC) was also applied in the simulated data. In this study patient-specific characteristics were used in computational anthropomorphic models for simulating realistic pathological patients. Voxel-by-voxel activity distribution with PVC within the tumor gives the most accurate results. Radiotherapy applications can utilize the benefits of the accurate realistic imaging simulations, using the anatomicaland biological information of each patient. Further work will incorporate the development of analytical anthropomorphic models with motion and cardiac correction, combined with pathological patients to achieve high accuracy in tumor imaging. This research was supported by the Joint Research and Technology Program between Greece and France; 2009-2011 (protocol ID: 09FR103). © 2012 American Association of Physicists in Medicine.

Does mental illness stigma contribute to adolescent standardized patients' discomfort with simulations of mental illness and adverse psychosocial experiences?

PubMed

Hanson, Mark D; Johnson, Samantha; Niec, Anne; Pietrantonio, Anna Marie; High, Bradley; MacMillan, Harriet; Eva, Kevin W

2008-01-01

Adolescent mental illness stigma-related factors may contribute to adolescent standardized patients' (ASP) discomfort with simulations of psychiatric conditions/adverse psychosocial experiences. Paradoxically, however, ASP involvement may provide a stigma-reduction strategy. This article reports an investigation of this hypothetical association between simulation discomfort and mental illness stigma. ASPs were randomly assigned to one of two simulation conditions: one was associated with mental illness stigma and one was not. ASP training methods included carefully written case simulations, educational materials, and active teaching methods. After training, ASPs completed the adapted Project Role Questionnaire to rate anticipated role discomfort with hypothetical adolescent psychiatric conditions/adverse psychosocial experiences and to respond to open-ended questions regarding this discomfort. A mixed design ANOVA was used to compare comfort levels across simulation conditions. Narrative responses to an open-ended question were reviewed for relevant themes. Twenty-four ASPs participated. A significant effect of simulation was observed, indicating that ASPs participating in the simulation associated with mental illness stigma anticipated greater comfort with portraying subsequent stigma-associated roles than did ASPs in the simulation not associated with stigma. ASPs' narrative responses regarding their reasons for anticipating discomfort focused upon the role of knowledge-related factors. ASPs' work with a psychiatric case simulation was associated with greater anticipated comfort with hypothetical simulations of psychiatric/adverse psychosocial conditions in comparison to ASPs lacking a similar work experience. The ASPs provided explanations for this anticipated discomfort that were suggestive of stigma-related knowledge factors. This preliminary research suggests an association between ASP anticipated role discomfort and mental illness stigma, and that ASP work may contribute to stigma reduction.

Progress in virtual reality simulators for surgical training and certification.

PubMed

de Visser, Hans; Watson, Marcus O; Salvado, Olivier; Passenger, Joshua D

2011-02-21

There is increasing evidence that educating trainee surgeons by simulation is preferable to traditional operating-room training methods with actual patients. Apart from reducing costs and risks to patients, training by simulation can provide some unique benefits, such as greater control over the training procedure and more easily defined metrics for assessing proficiency. Virtual reality (VR) simulators are now playing an increasing role in surgical training. However, currently available VR simulators lack the fidelity to teach trainees past the novice-to-intermediate skills level. Recent technological developments in other industries using simulation, such as the games and entertainment and aviation industries, suggest that the next generation of VR simulators should be suitable for training, maintenance and certification of advanced surgical skills. To be effective as an advanced surgical training and assessment tool, VR simulation needs to provide adequate and relevant levels of physical realism, case complexity and performance assessment. Proper validation of VR simulators and an increased appreciation of their value by the medical profession are crucial for them to be accepted into surgical training curricula.

Patient-specific 3D printing simulation to guide complex coronary intervention.

PubMed

Oliveira-Santos, Manuel; Oliveira Santos, Eduardo; Marinho, Ana Vera; Leite, Luís; Guardado, Jorge; Matos, Vítor; Pego, Guilherme Mariano; Marques, João Silva

2018-05-07

The field of three-dimensional printing applied to patient-specific simulation is evolving as a tool to enhance intervention results. We report the first case of a fully simulated percutaneous coronary intervention in a three-dimensional patient-specific model to guide treatment. An 85-year-old female presented with symptomatic in-stent restenosis in the ostial circumflex and was scheduled for percutaneous coronary intervention. Considering the complexity of the anatomy, patient setting and intervention technique, we elected to replicate the coronary anatomy using a three-dimensional model. In this way, we simulated the intervention procedure beforehand in the catheterization laboratory using standard materials. The procedure was guided by optical coherence tomography, with pre-dilatation of the lesion, implantation of a single drug-eluting stent in the ostial circumflex and kissing balloon inflation to the left anterior descending artery and circumflex. Procedural steps were replicated in the real patient's treatment, with remarkable parallelism in angiographic outcome and luminal gain at intracoronary imaging. In this proof-of-concept report, we show that patient-specific simulation is feasible to guide the treatment strategy of complex coronary artery disease. It enables the surgical team to plan and practice the procedure beforehand, and possibly predict complications and gain confidence. Copyright © 2018 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Toward numerical simulations of fluid-structure interactions for investigation of obstructive sleep apnea

NASA Astrophysics Data System (ADS)

Huang, Chien-Jung; Huang, Shao-Ching; White, Susan M.; Mallya, Sanjay M.; Eldredge, Jeff D.

2016-04-01

Obstructive sleep apnea (OSA) is a medical condition characterized by repetitive partial or complete occlusion of the airway during sleep. The soft tissues in the airway of OSA patients are prone to collapse under the low-pressure loads incurred during breathing. This paper describes efforts toward the development of a numerical tool for simulation of air-tissue interactions in the upper airway of patients with sleep apnea. A procedure by which patient-specific airway geometries are segmented and processed from dental cone-beam CT scans into signed distance fields is presented. A sharp-interface embedded boundary method based on the signed distance field is used on Cartesian grids for resolving the airflow in the airway geometries. For simulation of structure mechanics with large expected displacements, a cut-cell finite element method with nonlinear Green strains is used. The fluid and structure solvers are strongly coupled with a partitioned iterative algorithm. Preliminary results are shown for flow simulation inside the three-dimensional rigid upper airway of patients with obstructive sleep apnea. Two validation cases for the fluid-structure coupling problem are also presented.

Using Simulation to Examine the Effect of Physician Heterogeneity on the Operational Efficiency of an Overcrowded Hospital Emergency Department

NASA Astrophysics Data System (ADS)

Kuo, Y.-H.; Leung, J. M. Y.; Graham, C. A.

2015-05-01

In this paper, we present a case study of modelling and analyzing the patient flow of a hospital emergency department in Hong Kong. The emergency department is facing the challenge of overcrowding and the patients there usually experience a long waiting time. Our project team was requested by a senior consultant of the emergency department to analyze the patient flow and provide a decision support tool to help improve their operations. We adopt a simulation approach to mimic their daily operations. With the simulation model, we conduct a computational study to examine the effect of physician heterogeneity on the emergency department performance. We found that physician heterogeneity has a great impact on the operational efficiency and thus should be considered when developing simulation models. Our computational results show that, with the same average of service rates among the physicians, variation in the rates can improve overcrowding situation. This suggests that emergency departments may consider having some efficient physicians to speed up the overall service rate in return for more time for patients who need extra medical care.

Simulation in Occupational Therapy Curricula: A literature review.

PubMed

Bennett, Sally; Rodger, Sylvia; Fitzgerald, Cate; Gibson, Libby

2017-08-01

Simulated learning experiences are increasingly being used in health-care education to enhance student engagement and provide experiences that reflect clinical practice; however, simulation has not been widely investigated in occupational therapy curricula. The aim of this paper was to: (i) describe the existing research about the use and evaluation of simulation over the last three decades in occupational therapy curricula and (ii) consider how simulation has been used to develop competence in students. A literature review was undertaken with searches of MEDLINE, CINAHL and ERIC to locate articles that described or evaluated the use of simulation in occupational therapy curricula. Fifty-seven papers were identified. Occupational therapy educators have used the full scope of simulation modalities, including written case studies (22), standardised patients (13), video case studies (15), computer-based and virtual reality cases (7), role-play (8) and mannequins and part-task trainers (4). Ten studies used combinations of these modalities and two papers compared modalities. Most papers described the use of simulation for foundational courses, as for preparation for fieldwork, and to address competencies necessary for newly graduating therapists. The majority of studies were descriptive, used pre-post design, or were student's perceptions of the value of simulation. Simulation-based education has been used for a wide range of purposes in occupational therapy curricula and appears to be well received. Randomised controlled trials are needed to more accurately understand the effects of simulation not just for occupational therapy students but for longer term outcomes in clinical practice. © 2017 Occupational Therapy Australia.

[Clear cell carcinoma of the ovary simulating a yolk sac tumor].

PubMed

Bahri, Ibticem; Boudawara, Tahya; Khabir, Abdelmajid; Beyrouti, Mohamed Issam; Frikha, Mounir; Jlidi, Rachid

2003-04-01

Clear cell carcinoma (CCC) of the ovary is uncommon. In young patients, this tumor may simulate a yolk sac tumor. In this case, the morphologic distinction between these tumors is often difficult but the immunohistochemical staining for CA125 and alpha foeto protein (AFP) and the response to chemotherapy are particularly helpful to resolve this problem of differential diagnosis. We report a case of a 17 year old patient who was operated for a tumor of the right ovary. The diagnosis of a yolk sac tumor was first suggested. However, because of the non response to chemotherapy, a second laparotomy was performed; the definitive pathologic examination concluded to the diagnosis of a CCC of the ovary. The young age and the immunohistochemical staining for AFP are unusual and misleading features for a CCC. Our objective about this particular case is to discuss the anatomoclinical aspects of the CCC of the ovary and to prove the role of immunohistochemistry in the differential diagnosis.

Limitations of malaria reactive case detection in an area of low and unstable transmission on the Myanmar-Thailand border.

PubMed

Parker, Daniel M; Landier, Jordi; von Seidlein, Lorenz; Dondorp, Arjen; White, Lisa; Hanboonkunupakarn, Borimas; Maude, Richard J; Nosten, François H

2016-11-25

Reactive case detection is an approach that has been proposed as a tool for malaria elimination in low-transmission settings. It is an intuitively justified approach based on the concept of space-time clustering of malaria cases. When an index malaria clinical case is detected, it triggers reactive screening and treatment in the index house and neighbouring houses. However, the efficacy of this approach at varying screening radii and malaria prevalence remains ill defined. Data were obtained from a detailed demographic and geographic surveillance study in four villages on the Myanmar-Thailand border. Clinical cases were recorded at village malaria clinics and were linked back to patients' residencies. These data were used to simulate the efficacy of reactive case detection for clinical cases using rapid diagnostic tests (RDT). Simulations took clinical cases in a given month and tabulated the number of cases that would have been detected in the following month at varying screening radii around the index houses. Simulations were run independently for both falciparum and vivax malaria. Each simulation of a reactive case detection effort was run in comparison with a strategy using random selection of houses for screening. In approximately half of the screenings for falciparum and 10% for vivax it would have been impossible to detect any malaria cases regardless of the screening strategy because the screening would have occurred during times when there were no cases. When geographically linked cases were present in the simulation, reactive case detection would have only been successful at detecting most malaria cases using larger screening radii (150-m radius and above). At this screening radius and above, reactive case detection does not perform better than random screening of an equal number of houses in the village. Screening within very small radii detects only a very small proportion of cases, but despite this low performance is better than random screening with the same sample size. The results of these simulations indicate that reactive case detection for clinical cases using RDTs has limited ability in halting transmission in regions of low and unstable transmission. This is linked to high spatial heterogeneity of cases, acquisition of malaria infections outside the village, as well missing asymptomatic infections. When cases are few and sporadic, reactive case detection would result in major time and budgetary losses.

Routes for virtually guided endoscopic liver resection of subdiaphragmatic liver tumors.

PubMed

Aoki, Takeshi; Murakami, Masahiko; Fujimori, Akira; Koizumi, Tomotake; Enami, Yuta; Kusano, Tomokazu; Matsuda, Kazuhiro; Yamada, Kosuke; Nogaki, Koji; Wada, Yusuke; Hakozaki, Tomoki; Goto, Satoru; Watanabe, Makoto; Otsuka, Koji

2016-03-01

Laparoscopic and thoracoscopic/laparoscopic hepatectomy is a safe procedure that has potential advantages over open surgery. However, deeply positioned liver tumors require expert laparoscopic and thoracoscopic/laparoscopic hepatectomy techniques. Using simulated preoperative three-dimensional virtual endoscopy (P3DVE) guidance, we demonstrate herein that a thoracoscopic approach (TA), thoracoscopic-laparoscopic approach (TLA), and laparoscopic approach (LA) are all feasible and safe routes for performing pure laparoscopic and thoracoscopic/laparoscopic resection of liver tumors located in the 4a, 7, and 8 liver subdiaphragmatic areas. Thirty-eight patients underwent laparoscopic and thoracoscopic/laparoscopic partial liver resection (TA 13 cases, TLA two cases, and LA 23 cases) of the subdiaphragmatic area at Showa University Hospital. All surgical approaches were preoperatively determined based on preoperative 3D virtual endoscopic simulation (P3DVES) visualization and findings using the image processing software SYNAPSE VINCENT(®). Laparoscopic and thoracoscopic/laparoscopic liver resection was successfully performed for all cases under P3DVE instruction. The mean operative times using TA, TLA, and LA approaches were 193, 185, and 190 min, respectively. Mean blood loss during TA, TLA, and LA was 179, 138, and 73 g, respectively. No patients required conversion to open surgery, and there were no deaths, although there were three cases of Clavien-Dindo grade I in TA along with three cases of grade I and one case of grade II in LA. TA, TLA, and LA routes performed under P3DVE instruction are feasible and safe to perform for pure laparoscopic and thoracoscopic/laparoscopic liver resection in selected patients with lesions located in the hepatic subdiaphragmatic area.

An Experimental Study on the Effects of a Simulation Game on Students' Clinical Cognitive Skills and Motivation

ERIC Educational Resources Information Center

Dankbaar, Mary E. W.; Alsma, Jelmer; Jansen, Els E. H.; van Merrienboer, Jeroen J. G.; van Saase, Jan L. C. M.; Schuit, Stephanie C. E.

2016-01-01

Simulation games are becoming increasingly popular in education, but more insight in their critical design features is needed. This study investigated the effects of fidelity of open patient cases in adjunct to an instructional e-module on students' cognitive skills and motivation. We set up a three-group randomized post-test-only design: a…

Enhancing Competence in Health Social Work Education through Simulation-Based Learning: Strategies from a Case Study of a Family Session

ERIC Educational Resources Information Center

Craig, Shelley L.; McInroy, Lauren B.; Bogo, Marion; Thompson, Michelle

2017-01-01

Simulation-based learning (SBL) is a powerful tool for social work education, preparing students to practice in integrated health care settings. In an educational environment addressing patient health using an integrated care model, there is growing emphasis on students developing clinical competencies prior to entering clinical placements or…

RFA Guardian: Comprehensive Simulation of Radiofrequency Ablation Treatment of Liver Tumors.

PubMed

Voglreiter, Philip; Mariappan, Panchatcharam; Pollari, Mika; Flanagan, Ronan; Blanco Sequeiros, Roberto; Portugaller, Rupert Horst; Fütterer, Jurgen; Schmalstieg, Dieter; Kolesnik, Marina; Moche, Michael

2018-01-15

The RFA Guardian is a comprehensive application for high-performance patient-specific simulation of radiofrequency ablation of liver tumors. We address a wide range of usage scenarios. These include pre-interventional planning, sampling of the parameter space for uncertainty estimation, treatment evaluation and, in the worst case, failure analysis. The RFA Guardian is the first of its kind that exhibits sufficient performance for simulating treatment outcomes during the intervention. We achieve this by combining a large number of high-performance image processing, biomechanical simulation and visualization techniques into a generalized technical workflow. Further, we wrap the feature set into a single, integrated application, which exploits all available resources of standard consumer hardware, including massively parallel computing on graphics processing units. This allows us to predict or reproduce treatment outcomes on a single personal computer with high computational performance and high accuracy. The resulting low demand for infrastructure enables easy and cost-efficient integration into the clinical routine. We present a number of evaluation cases from the clinical practice where users performed the whole technical workflow from patient-specific modeling to final validation and highlight the opportunities arising from our fast, accurate prediction techniques.

Alice’s Delirium: A Theatre-based Simulation Scenario for Nursing

PubMed Central

Posner, Glenn D

2018-01-01

As an educational methodology, simulation has been used by nursing education at the academic level for numerous years and has started to gain traction in the onboarding education and professional development of practicing nurses. Simulation allows the learner to apply knowledge and skills in a safe environment where mistakes and learning can happen without an impact on patient safety. The development of a simulation scenario to demonstrate the benefits of simulation education methodologies to a large group of nurse educators was requested by nursing education leadership at The Ottawa Hospital (TOH). Since the demonstration of this scenario in the fall of 2016, there has been significant uptake and adaptation of this particular scenario within the nursing education departments of TOH. Originally written to be used with a simulated patient (SP), “Alice” has since been adapted to be used with a hi-fidelity manikin within an inpatient surgery department continuing professional development (CPD) program for practicing nurses, orientation for nurses to a level 2 trauma unit and at the corporate level of nursing orientation using an SP. Therefore, this scenario is applicable to nurses practicing in an area of inpatient surgery at varying levels, from novice to expert. It could easily be adapted for use with medicine nursing education programs. The case presented in this technical report is of the simulation scenario used for the inpatient surgery CPD program. Varying adaptations of the case are included in the appendices. PMID:29872592

Using a virtual patient system for the teaching of pharmaceutical care.

PubMed

Menendez, Elisa; Balisa-Rocha, Blície; Jabbur-Lopes, Monique; Costa, Wanderson; Nascimento, José Rafael; Dósea, Marcos; Silva, Leila; Lyra Junior, Divaldo

2015-09-01

The communication skills of pharmacists are essential for the identification and reduction of patient́s drug related problems. Therefore, Pharmacy courses started the process of teaching Pharmaceutical Care to students in order to improve their communication skills. The use of virtual patients (VP) has been a widely used technique in health care courses, but many of the VP tools in Pharmacy field are in English and do not have clinical cases that are common in tropical countries, such as Brazil. The aim of this work is to describe the PharmaVP system, developed with the purpose of training Latin America students in Pharmaceutical Care. The main differential of PharmaVP is the availability in three languages (Portuguese, English and Spanish) and the possibility of clinical case evolution, simulating several visits made by the patient. The system was developed according to an incremental and interactive methodology, well suited for conducting multidisciplinary projects. Real clinical cases were collected from a Pharmaceutical Care program and added in PharmaVP to simulate the virtual patients. Then, 31 students of a Pharmacy course were trained and invited to participate of the evaluation study. They used the software and answered adapted instruments that assess the students' acceptance of, use of, learning of, and satisfaction with the system. The results showed that the students found the cases realistic and learned significantly using the software. Another positive point is that the application process of PharmaVP did not consume much time. We can conclude that the virtual patient tool contributed to the development of the skills required for the practice of Pharmaceutical Care, but should be used as complementary technique. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Numerical simulations of post-surgical flow and thrombosis in basilar artery aneurysms

NASA Astrophysics Data System (ADS)

Seshadhri, Santhosh; Lawton, Michael; Boussel, Loic; Saloner, David; Rayz, Vitaliy

2015-11-01

Surgical treatment of basilar artery aneurysms presents a major challenge since it is crucial to preserve the flow to the vital brainstem perforators branching of the basilar artery. In some cases, basilar aneurysms can be treated by clipping vessels in order to induce flow reduction and aneurysm thrombosis. Patient-specific CFD models can provide guidance to clinicians by simulating postoperative flows resulting from alternative surgeries. Several surgical options were evaluated for four basilar aneurysm patients. Patient-specific models were generated from preoperative MR angiography and MR velocimetry data and modified to simulate different procedures. The Navier-Stokes equations were solved with a finite-volume solver Fluent. Virtual contrast injections were simulated by solving the advection-diffusion equation in order to estimate the flow residence time and determine thrombus-prone regions. The results indicated on procedures that reduce intra-aneurysmal velocities and flow regions which are likely to become thrombosed. Thus CFD modeling can help improve the outcome of surgeries altering the flow in basilar aneurysms.

Predictive validity of driving-simulator assessments following traumatic brain injury: a preliminary study.

PubMed

Lew, Henry L; Poole, John H; Lee, Eun Ha; Jaffe, David L; Huang, Hsiu-Chen; Brodd, Edward

2005-03-01

To evaluate whether driving simulator and road test evaluations can predict long-term driving performance, we conducted a prospective study on 11 patients with moderate to severe traumatic brain injury. Sixteen healthy subjects were also tested to provide normative values on the simulator at baseline. At their initial evaluation (time-1), subjects' driving skills were measured during a 30-minute simulator trial using an automated 12-measure Simulator Performance Index (SPI), while a trained observer also rated their performance using a Driving Performance Inventory (DPI). In addition, patients were evaluated on the road by a certified driving evaluator. Ten months later (time-2), family members observed patients driving for at least 3 hours over 4 weeks and rated their driving performance using the DPI. At time-1, patients were significantly impaired on automated SPI measures of driving skill, including: speed and steering control, accidents, and vigilance to a divided-attention task. These simulator indices significantly predicted the following aspects of observed driving performance at time-2: handling of automobile controls, regulation of vehicle speed and direction, higher-order judgment and self-control, as well as a trend-level association with car accidents. Automated measures of simulator skill (SPI) were more sensitive and accurate than observational measures of simulator skill (DPI) in predicting actual driving performance. To our surprise, the road test results at time-1 showed no significant relation to driving performance at time-2. Simulator-based assessment of patients with brain injuries can provide ecologically valid measures that, in some cases, may be more sensitive than a traditional road test as predictors of long-term driving performance in the community.

Design and evaluation of a simulation for pediatric dentistry in virtual worlds.

PubMed

Papadopoulos, Lazaros; Pentzou, Afroditi-Evaggelia; Louloudiadis, Konstantinos; Tsiatsos, Thrasyvoulos-Konstantinos

2013-10-29

Three-dimensional virtual worlds are becoming very popular among educators in the medical field. Virtual clinics and patients are already used for case study and role play in both undergraduate and continuing education levels. Dental education can also take advantage of the virtual world's pedagogical features in order to give students the opportunity to interact with virtual patients (VPs) and practice in treatment planning. The objective of this study was to design and evaluate a virtual patient as a supplemental teaching tool for pediatric dentistry. A child VP, called Erietta, was created by utilizing the programming and building tools that online virtual worlds offer. The case is about an eight-year old girl visiting the dentist with her mother for the first time. Communication techniques such as Tell-Show-Do and parents' interference management were the basic elements of the educational scenario on which the VP was based. An evaluation of the simulation was made by 103 dental students in their fourth year of study. Two groups were formed: an experimental group which was exposed to the simulation (n=52) and a control group which did not receive the simulation (n=51). At the end, both groups were asked to complete a knowledge questionnaire and the results were compared. A statistically significant difference between the two groups was found by applying a t test for independent samples (P<.001), showing a positive learning effect from the VP. The majority of the participants evaluated the aspects of the simulation very positively while 69% (36/52) of the simulation group expressed their preference for using this module as an additional teaching tool. This study demonstrated that a pediatric dentistry VP built in a virtual world offers significant learning potential when used as a supplement to the traditional teaching techniques.

Problem-based learning using patient-simulated videos showing daily life for a comprehensive clinical approach

PubMed Central

Ohira, Yoshiyuki; Uehara, Takanori; Noda, Kazutaka; Suzuki, Shingo; Shikino, Kiyoshi; Kajiwara, Hideki; Kondo, Takeshi; Hirota, Yusuke; Ikusaka, Masatomi

2017-01-01

Objectives We examined whether problem-based learning tutorials using patient-simulated videos showing daily life are more practical for clinical learning, compared with traditional paper-based problem-based learning, for the consideration rate of psychosocial issues and the recall rate for experienced learning. Methods Twenty-two groups with 120 fifth-year students were each assigned paper-based problem-based learning and video-based problem-based learning using patient-simulated videos. We compared target achievement rates in questionnaires using the Wilcoxon signed-rank test and discussion contents diversity using the Mann-Whitney U test. A follow-up survey used a chi-square test to measure students’ recall of cases in three categories: video, paper, and non-experienced. Results Video-based problem-based learning displayed significantly higher achievement rates for imagining authentic patients (p=0.001), incorporating a comprehensive approach including psychosocial aspects (p<0.001), and satisfaction with sessions (p=0.001). No significant differences existed in the discussion contents diversity regarding the International Classification of Primary Care Second Edition codes and chapter types or in the rate of psychological codes. In a follow-up survey comparing video and paper groups to non-experienced groups, the rates were higher for video (χ2=24.319, p<0.001) and paper (χ2=11.134, p=0.001). Although the video rate tended to be higher than the paper rate, no significant difference was found between the two. Conclusions Patient-simulated videos showing daily life facilitate imagining true patients and support a comprehensive approach that fosters better memory. The clinical patient-simulated video method is more practical and clinical problem-based tutorials can be implemented if we create patient-simulated videos for each symptom as teaching materials.  PMID:28245193

Problem-based learning using patient-simulated videos showing daily life for a comprehensive clinical approach.

PubMed

Ikegami, Akiko; Ohira, Yoshiyuki; Uehara, Takanori; Noda, Kazutaka; Suzuki, Shingo; Shikino, Kiyoshi; Kajiwara, Hideki; Kondo, Takeshi; Hirota, Yusuke; Ikusaka, Masatomi

2017-02-27

We examined whether problem-based learning tutorials using patient-simulated videos showing daily life are more practical for clinical learning, compared with traditional paper-based problem-based learning, for the consideration rate of psychosocial issues and the recall rate for experienced learning. Twenty-two groups with 120 fifth-year students were each assigned paper-based problem-based learning and video-based problem-based learning using patient-simulated videos. We compared target achievement rates in questionnaires using the Wilcoxon signed-rank test and discussion contents diversity using the Mann-Whitney U test. A follow-up survey used a chi-square test to measure students' recall of cases in three categories: video, paper, and non-experienced. Video-based problem-based learning displayed significantly higher achievement rates for imagining authentic patients (p=0.001), incorporating a comprehensive approach including psychosocial aspects (p<0.001), and satisfaction with sessions (p=0.001). No significant differences existed in the discussion contents diversity regarding the International Classification of Primary Care Second Edition codes and chapter types or in the rate of psychological codes. In a follow-up survey comparing video and paper groups to non-experienced groups, the rates were higher for video (χ 2 =24.319, p<0.001) and paper (χ 2 =11.134, p=0.001). Although the video rate tended to be higher than the paper rate, no significant difference was found between the two. Patient-simulated videos showing daily life facilitate imagining true patients and support a comprehensive approach that fosters better memory. The clinical patient-simulated video method is more practical and clinical problem-based tutorials can be implemented if we create patient-simulated videos for each symptom as teaching materials.

Agent Based Modeling of Atherosclerosis: A Concrete Help in Personalized Treatments

NASA Astrophysics Data System (ADS)

Pappalardo, Francesco; Cincotti, Alessandro; Motta, Alfredo; Pennisi, Marzio

Atherosclerosis, a pathology affecting arterial blood vessels, is one of most common diseases of the developed countries. We present studies on the increased atherosclerosis risk using an agent based model of atherogenesis that has been previously validated using clinical data. It is well known that the major risk in atherosclerosis is the persistent high level of low density lipoprotein (LDL) concentration. However, it is not known if short period of high LDL concentration can cause irreversible damage and if reduction of the LDL concentration (either by life style or drug) can drastically or partially reduce the already acquired risk. We simulated four different clinical situations in a large set of virtual patients (200 per clinical scenario). In the first one the patients lifestyle maintains the concentration of LDL in a no risk range. This is the control case simulation. The second case is represented by patients having high level of LDL with a delay to apply appropriate treatments; The third scenario is characterized by patients with high LDL levels treated with specific drugs like statins. Finally we simulated patients that are characterized by several oxidative events (smoke, sedentary life style, assumption of alcoholic drinks and so on so forth) that effective increase the risk of LDL oxidation. Those preliminary results obviously need to be clinically investigated. It is clear, however, that SimAthero has the power to concretely help medical doctors and clinicians in choosing personalized treatments for the prevention of the atherosclerosis damages.

The safe use of automated external defibrillators in a wet environment.

PubMed

Lyster, Tom; Jorgenson, Dawn; Morgan, Carl

2003-01-01

There has been concern regarding potential shock hazards for rescuers or bystanders when a defibrillator is used in a wet environment and the recommended safety procedure, moving the patient to a dry area, is not followed. To measure the electrical potentials associated with the use of an automated external defibrillator (AED) in a realistically modeled wet environment. A raw processed turkey was used as a patient surrogate. The turkey was placed on a cement floor while pool water was applied to the surrounding area. To simulate a rescuer or bystander in the vicinity of a patient, a custom sense probe was constructed. Defibrillation shocks were delivered to the turkey and the probe was used to measure the voltage an operator/bystander would receive at different points surrounding the surrogate. The test was repeated with salt water. The maximum voltage occurred approximately 15 cm from the simulated patient and measured 14 V peak (current 14 mA peak) in the case of pool water, and 30 V peak (current 30 mA peak) in the case of salt water. Thirty volts may result in some minor sensation by the operator or bystander, but is considered unlikely to be hazardous under these circumstances. The maximum currents were lower than allowed by safety standards. Although defibrillation in a wet environment is not recommended practice, our simulation of a patient and a rescuer/bystander in a wet environment did not show significant risk should circumstances demand it.

Estimating the hemodynamic impact of interventional treatments of aneurysms: numerical simulation with experimental validation: technical case report.

PubMed

Acevedo-Bolton, Gabriel; Jou, Liang-Der; Dispensa, Bradley P; Lawton, Michael T; Higashida, Randall T; Martin, Alastair J; Young, William L; Saloner, David

2006-08-01

The goal of this study was to use phase-contrast magnetic resonance imaging and computational fluid dynamics to estimate the hemodynamic outcome that might result from different interventional options for treating a patient with a giant fusiform aneurysm. We followed a group of patients with giant intracranial aneurysms who have no clear surgical options. One patient demonstrated dramatic aneurysm growth and was selected for further analysis. The aneurysm geometry and input and output flow conditions were measured with contrast-enhanced magnetic resonance angiography and phase-contrast magnetic resonance imaging. The data was imported into a computational fluid dynamics program and the velocity fields and wall shear stress distributions were calculated for the presenting physiological condition and for cases in which the opposing vertebral arteries were either occluded or opened. These models were validated with in vitro flow experiments using a geometrically exact silicone flow phantom. Simulation indicated that altering the flow ratio in the two vertebrals would deflect the main blood jet into the aneurysm belly, and that this would likely reduce the extent of the region of low wall shear stress in the growth zone. Computational fluid dynamics flow simulations in a complex patient-specific aneurysm geometry were validated by in vivo and in vitro phase-contrast magnetic resonance imaging, and were shown to be useful in modeling the likely hemodynamic impact of interventional treatment of the aneurysm.

Clinical use of Nintendo Wii bowling simulation to decrease fall risk in an elderly resident of a nursing home: a case report.

PubMed

Clark, Robert; Kraemer, Theresa

2009-01-01

Of the estimated 1.7 million residents of nursing homes in the United States, approximately half fall annually; and 11% of these sustain injury. This is twice the rate for persons dwelling in the community. By addressing fall risk, physical therapists have an opportunity to reduce falls which are the leading cause of injury deaths, as well as the most common cause of nonfatal injuries for older adults in the United States. This case report examines the effect of a novel interactive video game intervention to address balance dysfunction in an elderly resident of a nursing home who was at risk for falls. The patient is an 89-year-old resident diagnosed with an unspecified balance disorder and a history of multiple falls. Self reports of gait abnormalities, scores on several clinical measures, and her fall history classified her as having substantial risk for future falls. A nontraditional approach to balance training, employing the Nintendo Wii bowling simulation, was used as intervention for this patient's balance disorder. After 6 one-hour treatment sessions, the patient's Berg Balance Score improved from 48 to 53. On the Dynamic Gait Index, the patient improved her score from 19 to 21. The patient's Timed Up and Go Test improved from 14.9 to 10.5 seconds, all suggesting a reduced risk of falling. The patient's ABC Score improved from 88 to 90%. Physical therapy intervention, using the Nintendo Wii bowling simulation, may have decreased fall risk for this individual.

Impact of vaginal-rectal ultrasound examinations with covered and low-level disinfected transducers on infectious transmissions in france.

PubMed

Leroy, Sandrine; M'Zali, Fatima; Kann, Michael; Weber, David J; Smith, David D

2014-12-01

The risk of cross-infection from shared ultrasound probes in endorectal and vaginal ultrasonography due to low-level disinfection (LLD) is difficult to estimate because potential infections are also sexually transmitted diseases, and route of contamination is often difficult to establish. In France, the widely used standard for prevention of infections is through the use of probe covers and LLD of the ultrasound transducer by disinfectant wipes. We performed an in silico simulation based on a systematic review to estimate the number of patients infected after endorectal or vaginal ultrasonography examination using LLD for probes. We performed a stochastic Monte Carlo computer simulation to produce hypothetical cohorts for a population of 4 million annual ultrasound examinations performed in France, and we estimated the number of infected patients for human immunodeficiency virus (HIV), herpes simplex virus, hepatitis B virus, hepatitis C virus, human papilloma virus, cytomegalovirus, and Chlamydia trachomatis. Modeling parameters were estimated by meta-analysis when possible. The probability of infection from a contaminated probe ranged from 1% to 6%, depending on the pathogen. For cases of HIV infection, this would result in approximately 60 infected patients per year. For other common viral infections, the number of new cases ranged from 1,600 to 15,000 per year that could be attributable directly to ultrasound and LLD procedures. Our simulation results showed that, despite cumulative use of probe cover and LLD, there were still some cases of de novo infection that may be attributable to ultrasound procedures. These cases are preventable by reviewing the currently used LLD and/or upgrading LLD to high-level disinfection, as recommended by the US Centers for Disease Control and Prevention.

Case-based learning and simulation: useful tools to enhance nurses' education? Nonrandomized controlled trial.

PubMed

Raurell-Torredà, Marta; Olivet-Pujol, Josep; Romero-Collado, Àngel; Malagon-Aguilera, Maria Carmen; Patiño-Masó, Josefina; Baltasar-Bagué, Alícia

2015-01-01

To compare skills acquired by undergraduate nursing students enrolled in a medical-surgical course. To compare skills demonstrated by students with no previous clinical practice (undergraduates) and nurses with clinical experience enrolled in continuing professional education (CPE). In a nonrandomized clinical trial, 101 undergraduates enrolled in the "Adult Patients 1" course were assigned to the traditional lecture and discussion (n = 66) or lecture and discussion plus case-based learning (n = 35) arm of the study; 59 CPE nurses constituted a comparison group to assess the effects of previous clinical experience on learning outcomes. Scores on an objective structured clinical examination (OSCE), using a human patient simulator and cases validated by the National League for Nursing, were compared for the undergraduate control and intervention groups, and for CPE nurses (Student's t test). Controls scored lower than the intervention group on patient assessment (6.3 ± 2.3 vs 7.5 ± 1.4, p = .04, mean difference, -1.2 [95% confidence interval (CI) -2.4 to -0.03]) but the intervention group did not differ from CPE nurses (7.5 ± 1.4 vs 8.8 ± 1.5, p = .06, mean difference, -1.3 [95% CI -2.6 to 0.04]). The CPE nurses committed more "rules-based errors" than did undergraduates, specifically patient identifications (77.2% vs 55%, p = .7) and checking allergies before administering medication (68.2% vs 60%, p = .1). The intervention group developed better patient assessment skills than the control group. Case-based learning helps to standardize the process, which can contribute to quality and consistency in practice: It is essential to correctly identify a problem in order to treat it. Clinical experience of CPE nurses was not associated with better adherence to safety protocols. Case-based learning improves the patient assessment skills of undergraduate nursing students, thereby preparing them for clinical practice. © 2014 Sigma Theta Tau International.

Quantification of gross tumour volume changes between simulation and first day of radiotherapy for patients with locally advanced malignancies of the lung and head/neck.

PubMed

Kishan, Amar U; Cui, Jing; Wang, Pin-Chieh; Daly, Megan E; Purdy, James A; Chen, Allen M

2014-10-01

To quantify changes in gross tumour volume (GTV) between simulation and initiation of radiotherapy in patients with locally advanced malignancies of the lung and head/neck. Initial cone beam computed tomography (CT) scans from 12 patients with lung cancer and 12 with head/neck cancer (head and neck squamous cell carcinoma (HNSCC)) treated with intensity-modulated radiotherapy with image guidance were rigidly registered to the simulation CT scans. The GTV was demarcated on both scans. The relationship between percent GTV change and variables including time interval between simulation and start, tumour (T) stage, and absolute weight change was assessed. For lung cancer patients, the GTV increased a median of 35.06% (range, -16.63% to 229.97%) over a median interval of 13 days (range, 7-43), while for HNSCC patients, the median GTV increase was 16.04% (range, -8.03% to 47.41%) over 13 days (range, 7-40). These observed changes are statistically significant. The magnitude of this change was inversely associated with the size of the tumour on the simulation scan for lung cancer patients (P < 0.05). However, the observed changes in GTV did not correlate with the duration of the interval for either disease site. Similarly, T stage, absolute weight change and histologic type (the latter for lung cancer cases) did not correlate with degree of GTV change (P > 0.1). While the observed changes in GTV were moderate from the time of simulation to start of radiotherapy, these findings underscore the importance of image guidance for target localisation and verification, particularly for smaller tumours. Minimising the delay between simulation and treatment initiation may also be beneficial. © 2014 The Royal Australian and New Zealand College of Radiologists.

Log file-based patient dose calculations of double-arc VMAT for head-and-neck radiotherapy.

PubMed

Katsuta, Yoshiyuki; Kadoya, Noriyuki; Fujita, Yukio; Shimizu, Eiji; Majima, Kazuhiro; Matsushita, Haruo; Takeda, Ken; Jingu, Keiichi

2018-04-01

The log file-based method cannot display dosimetric changes due to linac component miscalibration because of the insensitivity of log files to linac component miscalibration. The purpose of this study was to supply dosimetric changes in log file-based patient dose calculations for double-arc volumetric-modulated arc therapy (VMAT) in head-and-neck cases. Fifteen head-and-neck cases participated in this study. For each case, treatment planning system (TPS) doses were produced by double-arc and single-arc VMAT. Miscalibration-simulated log files were generated by inducing a leaf miscalibration of ±0.5 mm into the log files that were acquired during VMAT irradiation. Subsequently, patient doses were estimated using the miscalibration-simulated log files. For double-arc VMAT, regarding planning target volume (PTV), the change from TPS dose to miscalibration-simulated log file dose in D mean was 0.9 Gy and that for tumor control probability was 1.4%. As for organ-at-risks (OARs), the change in D mean was <0.7 Gy and normal tissue complication probability was <1.8%. A comparison between double-arc and single-arc VMAT for PTV showed statistically significant differences in the changes evaluated by D mean and radiobiological metrics (P < 0.01), even though the magnitude of these differences was small. Similarly, for OARs, the magnitude of these changes was found to be small. Using the log file-based method for PTV and OARs, the log file-based method estimate of patient dose using the double-arc VMAT has accuracy comparable to that obtained using the single-arc VMAT. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Stroke code simulation benefits advanced practice providers similar to neurology residents.

PubMed

Khan, Muhib; Baird, Grayson L; Price, Theresa; Tubergen, Tricia; Kaskar, Omran; De Jesus, Michelle; Zachariah, Joseph; Oostema, Adam; Scurek, Raymond; Coleman, Robert R; Sherman, Wendy; Hingtgen, Cynthia; Abdelhak, Tamer; Smith, Brien; Silver, Brian

2018-04-01

Advanced practice providers (APPs) are important members of stroke teams. Stroke code simulations offer valuable experience in the evaluation and treatment of stroke patients without compromising patient care. We hypothesized that simulation training would increase APP confidence, comfort level, and preparedness in leading a stroke code similar to neurology residents. This is a prospective quasi-experimental, pretest/posttest study. Nine APPs and 9 neurology residents participated in 3 standardized simulated cases to determine need for IV thrombolysis, thrombectomy, and blood pressure management for intracerebral hemorrhage. Emergency medicine physicians and neurologists were preceptors. APPs and residents completed a survey before and after the simulation. Generalized mixed modeling assuming a binomial distribution was used to evaluate change. On a 5-point Likert scale (1 = strongly disagree and 5 = strongly agree), confidence in leading a stroke code increased from 2.4 to 4.2 ( p < 0.05) among APPs. APPs reported improved comfort level in rapidly assessing a stroke patient for thrombolytics (3.1-4.2; p < 0.05), making the decision to give thrombolytics (2.8 vs 4.2; p < 0.05), and assessing a patient for embolectomy (2.4-4.0; p < 0.05). There was no difference in the improvement observed in all the survey questions as compared to neurology residents. Simulation training is a beneficial part of medical education for APPs and should be considered in addition to traditional didactics and clinical training. Further research is needed to determine whether simulation education of APPs results in improved treatment times and outcomes of acute stroke patients.

A Process and Programming Design to Develop Virtual Patients for Medical Education

PubMed Central

McGee, James B.; Wu, Martha

1999-01-01

Changes in the financing and delivery of healthcare in our nation's teaching hospitals have diminished the variety and quality of a medical student's clinical training. The Virtual Patient Project is a series of computer-based, multimedia, clinical simulations, designed to fill this gap. After the development of a successful prototype and obtaining funding for a series of 16 cases, a method to write and produce many virtual patients was created. Case authors now meet with our production team to write and edit a movie-like script. This script is converted into a design document which specifies the clinical aspects, teaching points, media production, and interactivity of each case. The program's code was modularized, using object-oriented techniques, to allow for the variations in cases and for team programming. All of the clinical and teaching content is stored in a database, that allows for faster and easier editing by many persons simultaneously.

Improved scores for observed teamwork in the clinical environment following a multidisciplinary operating room simulation intervention.

PubMed

Weller, Jennifer M; Cumin, David; Civil, Ian D; Torrie, Jane; Garden, Alexander; MacCormick, Andrew D; Gurusinghe, Nishanthi; Boyd, Matthew J; Frampton, Christopher; Cokorilo, Martina; Tranvik, Magnus; Carlsson, Lisa; Lee, Tracey; Ng, Wai Leap; Crossan, Michael; Merry, Alan F

2016-08-05

We ran a Multidisciplinary Operating Room Simulation (MORSim) course for 20 complete general surgical teams from two large metropolitan hospitals. Our goal was to improve teamwork and communication in the operating room (OR). We hypothesised that scores for teamwork and communication in the OR would improve back in the workplace following MORSim. We used an extended Behavioural Marker Risk Index (BMRI) to measure teamwork and communication, because a relationship has previously been documented between BMRI scores and surgical patient outcomes. Trained observers scored general surgical teams in the OR at the two study hospitals before and after MORSim, using the BMRI. Analysis of BMRI scores for the 224 general surgical cases before and 213 cases after MORSim showed BMRI scores improved by more than 20% (0.41 v 0.32, p<0.001). Previous research suggests that this improved teamwork score would translate into a clinically important reduction in complications and mortality in surgical patients. We demonstrated an improvement in scores for teamwork and communication in general surgical ORs following our intervention. These results support the use of simulation-based multidisciplinary team training for OR staff to promote better teamwork and communication, and potentially improve outcomes for general surgical patients.

Evaluation of an interactive case simulation system in dermatology and venereology for medical students

PubMed Central

Wahlgren, Carl-Fredrik; Edelbring, Samuel; Fors, Uno; Hindbeck, Hans; Ståhle, Mona

2006-01-01

Background Most of the many computer resources used in clinical teaching of dermatology and venereology for medical undergraduates are information-oriented and focus mostly on finding a "correct" multiple-choice alternative or free-text answer. We wanted to create an interactive computer program, which facilitates not only factual recall but also clinical reasoning. Methods Through continuous interaction with students, a new computerised interactive case simulation system, NUDOV, was developed. It is based on authentic cases and contains images of real patients, actors and healthcare providers. The student selects a patient and proposes questions for medical history, examines the skin, and suggests investigations, diagnosis, differential diagnoses and further management. Feedback is given by comparing the user's own suggestions with those of a specialist. In addition, a log file of the student's actions is recorded. The program includes a large number of images, video clips and Internet links. It was evaluated with a student questionnaire and by randomising medical students to conventional teaching (n = 85) or conventional teaching plus NUDOV (n = 31) and comparing the results of the two groups in a final written examination. Results The questionnaire showed that 90% of the NUDOV students stated that the program facilitated their learning to a large/very large extent, and 71% reported that extensive working with authentic computerised cases made it easier to understand and learn about diseases and their management. The layout, user-friendliness and feedback concept were judged as good/very good by 87%, 97%, and 100%, respectively. Log files revealed that the students, in general, worked with each case for 60–90 min. However, the intervention group did not score significantly better than the control group in the written examination. Conclusion We created a computerised case simulation program allowing students to manage patients in a non-linear format supporting the clinical reasoning process. The student gets feedback through comparison with a specialist, eliminating the need for external scoring or correction. The model also permits discussion of case processing, since all transactions are stored in a log file. The program was highly appreciated by the students, but did not significantly improve their performance in the written final examination. PMID:16907972

Use of ultraviolet-fluorescence-based simulation in evaluation of personal protective equipment worn for first assessment and care of a patient with suspected high-consequence infectious disease.

PubMed

Hall, S; Poller, B; Bailey, C; Gregory, S; Clark, R; Roberts, P; Tunbridge, A; Poran, V; Evans, C; Crook, B

2018-06-01

Variations currently exist across the UK in the choice of personal protective equipment (PPE) used by healthcare workers when caring for patients with suspected high-consequence infectious diseases (HCIDs). To test the protection afforded to healthcare workers by current PPE ensembles during assessment of a suspected HCID case, and to provide an evidence base to justify proposal of a unified PPE ensemble for healthcare workers across the UK. One 'basic level' (enhanced precautions) PPE ensemble and five 'suspected case' PPE ensembles were evaluated in volunteer trials using 'Violet'; an ultraviolet-fluorescence-based simulation exercise to visualize exposure/contamination events. Contamination was photographed and mapped. There were 147 post-simulation and 31 post-doffing contamination events, from a maximum of 980, when evaluating the basic level of PPE. Therefore, this PPE ensemble did not afford adequate protection, primarily due to direct contamination of exposed areas of the skin. For the five suspected case ensembles, 1584 post-simulation contamination events were recorded, from a maximum of 5110. Twelve post-doffing contamination events were also observed (face, two events; neck, one event; forearm, one event; lower legs, eight events). All suspected case PPE ensembles either had post-doffing contamination events or other significant disadvantages to their use. This identified the need to design a unified PPE ensemble and doffing procedure, incorporating the most protective PPE considered for each body area. This work has been presented to, and reviewed by, key stakeholders to decide on a proposed unified ensemble, subject to further evaluation. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Assessing Critical Thinking Outcomes of Dental Hygiene Students Utilizing Virtual Patient Simulation: A Mixed Methods Study.

PubMed

Allaire, Joanna L

2015-09-01

Dental hygiene educators must determine which educational practices best promote critical thinking, a quality necessary to translate knowledge into sound clinical decision making. The aim of this small pilot study was to determine whether virtual patient simulation had an effect on the critical thinking of dental hygiene students. A pretest-posttest design using the Health Science Reasoning Test was used to evaluate the critical thinking skills of senior dental hygiene students at The University of Texas School of Dentistry at Houston Dental Hygiene Program before and after their experience with computer-based patient simulation cases. Additional survey questions sought to identify the students' perceptions of whether the experience had helped develop their critical thinking skills and improved their ability to provide competent patient care. A convenience sample of 31 senior dental hygiene students completed both the pretest and posttest (81.5% of total students in that class); 30 senior dental hygiene students completed the survey on perceptions of the simulation (78.9% response rate). Although the results did not show a significant increase in mean scores, the students reported feeling that the use of virtual patients was an effective teaching method to promote critical thinking, problem-solving, and confidence in the clinical realm. The results of this pilot study may have implications to support the use of virtual patient simulations in dental hygiene education. Future research could include a larger controlled study to validate findings from this study.

3D Rapid Prototyping for Otolaryngology-Head and Neck Surgery: Applications in Image-Guidance, Surgical Simulation and Patient-Specific Modeling.

PubMed

Chan, Harley H L; Siewerdsen, Jeffrey H; Vescan, Allan; Daly, Michael J; Prisman, Eitan; Irish, Jonathan C

2015-01-01

The aim of this study was to demonstrate the role of advanced fabrication technology across a broad spectrum of head and neck surgical procedures, including applications in endoscopic sinus surgery, skull base surgery, and maxillofacial reconstruction. The initial case studies demonstrated three applications of rapid prototyping technology are in head and neck surgery: i) a mono-material paranasal sinus phantom for endoscopy training ii) a multi-material skull base simulator and iii) 3D patient-specific mandible templates. Digital processing of these phantoms is based on real patient or cadaveric 3D images such as CT or MRI data. Three endoscopic sinus surgeons examined the realism of the endoscopist training phantom. One experienced endoscopic skull base surgeon conducted advanced sinus procedures on the high-fidelity multi-material skull base simulator. Ten patients participated in a prospective clinical study examining patient-specific modeling for mandibular reconstructive surgery. Qualitative feedback to assess the realism of the endoscopy training phantom and high-fidelity multi-material phantom was acquired. Conformance comparisons using assessments from the blinded reconstructive surgeons measured the geometric performance between intra-operative and pre-operative reconstruction mandible plates. Both the endoscopy training phantom and the high-fidelity multi-material phantom received positive feedback on the realistic structure of the phantom models. Results suggested further improvement on the soft tissue structure of the phantom models is necessary. In the patient-specific mandible template study, the pre-operative plates were judged by two blinded surgeons as providing optimal conformance in 7 out of 10 cases. No statistical differences were found in plate fabrication time and conformance, with pre-operative plating providing the advantage of reducing time spent in the operation room. The applicability of common model design and fabrication techniques across a variety of otolaryngological sub-specialties suggests an emerging role for rapid prototyping technology in surgical education, procedure simulation, and clinical practice.

Frequency and Clinical Significance of Previously Undetected Incidental Findings Detected on Computed Tomography Simulation Scans for Breast Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakamura, Naoki, E-mail: naokinak@luke.or.jp; Tsunoda, Hiroko; Takahashi, Osamu

2012-11-01

Purpose: To determine the frequency and clinical significance of previously undetected incidental findings found on computed tomography (CT) simulation images for breast cancer patients. Methods and Materials: All CT simulation images were first interpreted prospectively by radiation oncologists and then double-checked by diagnostic radiologists. The official reports of CT simulation images for 881 consecutive postoperative breast cancer patients from 2009 to 2010 were retrospectively reviewed. Potentially important incidental findings (PIIFs) were defined as any previously undetected benign or malignancy-related findings requiring further medical follow-up or investigation. For all patients in whom a PIIF was detected, we reviewed the clinical recordsmore » to determine the clinical significance of the PIIF. If the findings from the additional studies prompted by a PIIF required a change in management, the PIIF was also recorded as a clinically important incidental finding (CIIF). Results: There were a total of 57 (6%) PIIFs. The 57 patients in whom a PIIF was detected were followed for a median of 17 months (range, 3-26). Six cases of CIIFs (0.7% of total) were detected. Of the six CIIFs, three (50%) cases had not been noted by the radiation oncologist until the diagnostic radiologist detected the finding. On multivariate analysis, previous CT examination was an independent predictor for PIIF (p = 0.04). Patients who had not previously received chest CT examinations within 1 year had a statistically significantly higher risk of PIIF than those who had received CT examinations within 6 months (odds ratio, 3.54; 95% confidence interval, 1.32-9.50; p = 0.01). Conclusions: The rate of incidental findings prompting a change in management was low. However, radiation oncologists appear to have some difficulty in detecting incidental findings that require a change in management. Considering cost, it may be reasonable that routine interpretations are given to those who have not received previous chest CT examinations within 1 year.« less

3D Rapid Prototyping for Otolaryngology—Head and Neck Surgery: Applications in Image-Guidance, Surgical Simulation and Patient-Specific Modeling

PubMed Central

Chan, Harley H. L.; Siewerdsen, Jeffrey H.; Vescan, Allan; Daly, Michael J.; Prisman, Eitan; Irish, Jonathan C.

2015-01-01

The aim of this study was to demonstrate the role of advanced fabrication technology across a broad spectrum of head and neck surgical procedures, including applications in endoscopic sinus surgery, skull base surgery, and maxillofacial reconstruction. The initial case studies demonstrated three applications of rapid prototyping technology are in head and neck surgery: i) a mono-material paranasal sinus phantom for endoscopy training ii) a multi-material skull base simulator and iii) 3D patient-specific mandible templates. Digital processing of these phantoms is based on real patient or cadaveric 3D images such as CT or MRI data. Three endoscopic sinus surgeons examined the realism of the endoscopist training phantom. One experienced endoscopic skull base surgeon conducted advanced sinus procedures on the high-fidelity multi-material skull base simulator. Ten patients participated in a prospective clinical study examining patient-specific modeling for mandibular reconstructive surgery. Qualitative feedback to assess the realism of the endoscopy training phantom and high-fidelity multi-material phantom was acquired. Conformance comparisons using assessments from the blinded reconstructive surgeons measured the geometric performance between intra-operative and pre-operative reconstruction mandible plates. Both the endoscopy training phantom and the high-fidelity multi-material phantom received positive feedback on the realistic structure of the phantom models. Results suggested further improvement on the soft tissue structure of the phantom models is necessary. In the patient-specific mandible template study, the pre-operative plates were judged by two blinded surgeons as providing optimal conformance in 7 out of 10 cases. No statistical differences were found in plate fabrication time and conformance, with pre-operative plating providing the advantage of reducing time spent in the operation room. The applicability of common model design and fabrication techniques across a variety of otolaryngological sub-specialties suggests an emerging role for rapid prototyping technology in surgical education, procedure simulation, and clinical practice. PMID:26331717

A simulation framework for mapping risks in clinical processes: the case of in-patient transfers.

PubMed

Dunn, Adam G; Ong, Mei-Sing; Westbrook, Johanna I; Magrabi, Farah; Coiera, Enrico; Wobcke, Wayne

2011-05-01

To model how individual violations in routine clinical processes cumulatively contribute to the risk of adverse events in hospital using an agent-based simulation framework. An agent-based simulation was designed to model the cascade of common violations that contribute to the risk of adverse events in routine clinical processes. Clinicians and the information systems that support them were represented as a group of interacting agents using data from direct observations. The model was calibrated using data from 101 patient transfers observed in a hospital and results were validated for one of two scenarios (a misidentification scenario and an infection control scenario). Repeated simulations using the calibrated model were undertaken to create a distribution of possible process outcomes. The likelihood of end-of-chain risk is the main outcome measure, reported for each of the two scenarios. The simulations demonstrate end-of-chain risks of 8% and 24% for the misidentification and infection control scenarios, respectively. Over 95% of the simulations in both scenarios are unique, indicating that the in-patient transfer process diverges from prescribed work practices in a variety of ways. The simulation allowed us to model the risk of adverse events in a clinical process, by generating the variety of possible work subject to violations, a novel prospective risk analysis method. The in-patient transfer process has a high proportion of unique trajectories, implying that risk mitigation may benefit from focusing on reducing complexity rather than augmenting the process with further rule-based protocols.

Defining the Correctness of a Diagnosis: Differential Judgments and Expert Knowledge

ERIC Educational Resources Information Center

Kanter, Steven L.; Brosenitsch, Teresa A.; Mahoney, John F.; Staszewski, James

2010-01-01

Approaches that use a simulated patient case to study and assess diagnostic reasoning usually use the correct diagnosis of the case as a measure of success and as an anchor for other measures. Commonly, the correctness of a diagnosis is determined by the judgment of one or more experts. In this study, the consistency of experts' judgments of the…

Blended E-learning in a Web-based virtual hospital: a useful tool for undergraduate education in urology.

PubMed

Horstmann, M; Renninger, M; Hennenlotter, J; Horstmann, C C; Stenzl, A

2009-08-01

E-learning is a teaching tool used successfully in many medical subspecialties. Experience with its use in urology, however, is scarce. We present our teaching experience with the INMEDEA simulator to teach urological care to medical students. The INMEDEA simulator is an interactive e-learning system built around a virtual hospital which includes a department of urology. It allows students to solve virtual patient cases online. In this study, students were asked to prepare two urological cases prior to discussion of the cases in small groups. This blended teaching approach was evaluated by students through anonymous questionnaires. Of 70 4th year medical students 76% judged this teaching method as good or very good. Eighty-seven percent felt that it offered a good way to understand urological diseases better and 72% felt that learning with this method was fun. Nevertheless, 30 out of 70 free text statements revealed that further improvements of the program, including an easier and more comfortable navigation and a faster supply of information are necessary. Virtual patient cases offer a practicable solution for teaching based on problem solving in urology with a high acceptance rate by students.

Structured communication: teaching delivery of difficult news with simulated resuscitations in an emergency medicine clerkship.

PubMed

Lamba, Sangeeta; Nagurka, Roxanne; Offin, Michael; Scott, Sandra R

2015-03-01

The objective is to describe the implementation and outcomes of a structured communication module used to supplement case-based simulated resuscitation training in an emergency medicine (EM) clerkship. We supplemented two case-based simulated resuscitation scenarios (cardiac arrest and blunt trauma) with role-play in order to teach medical students how to deliver news of death and poor prognosis to family of the critically ill or injured simulated patient. Quantitative outcomes were assessed with pre and post-clerkship surveys. Secondarily, students completed a written self-reflection (things that went well and why; things that did not go well and why) to further explore learner experiences with communication around resuscitation. Qualitative analysis identified themes from written self-reflections. A total of 120 medical students completed the pre and post-clerkship surveys. Majority of respondents reported that they had witnessed or role-played the delivery of difficult news, but only few had real-life experience of delivering news of death (20/120, 17%) and poor prognosis (34/120, 29%). This communication module led to statistically significant increased scores for comfort, confidence, and knowledge with communicating difficult news of death and poor prognosis. Pre-post scores increased for those agreeing with statements (somewhat/very much) for delivery of news of poor prognosis: comfort 69% to 81%, confidence 66% to 81% and knowledge 76% to 90% as well as for statements regarding delivery of news of death: comfort 52% to 68%, confidence 57% to 76% and knowledge 76% to 90%. Respondents report that patient resuscitations (simulated and/or real) generated a variety of strong emotional responses such as anxiety, stress, grief and feelings of loss and failure. A structured communication module supplements simulated resuscitation training in an EM clerkship and leads to a self-reported increase in knowledge, comfort, and competence in communicating difficult news of death and poor prognosis to family. Educators may need to seek ways to address the strong emotions generated in learners with real and simulated patient resuscitations.

Protocol for concomitant temporomandibular joint custom-fitted total joint reconstruction and orthognathic surgery utilizing computer-assisted surgical simulation.

PubMed

Movahed, Reza; Teschke, Marcus; Wolford, Larry M

2013-12-01

Clinicians who address temporomandibular joint (TMJ) pathology and dentofacial deformities surgically can perform the surgery in 1 stage or 2 separate stages. The 2-stage approach requires the patient to undergo 2 separate operations and anesthesia, significantly prolonging the overall treatment. However, performing concomitant TMJ and orthognathic surgery (CTOS) in these cases requires careful treatment planning and surgical proficiency in the 2 surgical areas. This article presents a new treatment protocol for the application of computer-assisted surgical simulation in CTOS cases requiring reconstruction with patient-fitted total joint prostheses. The traditional and new CTOS protocols are described and compared. The new CTOS protocol helps decrease the preoperative workup time and increase the accuracy of model surgery. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

The role of simulation in neurosurgical education: a survey of 99 United States neurosurgery program directors.

PubMed

Ganju, Aruna; Aoun, Salah G; Daou, Marc R; El Ahmadieh, Tarek Y; Chang, Alice; Wang, Lucy; Batjer, H Hunt; Bendok, Bernard R

2013-11-01

With the reduction of resident work hours and the increasing focus on patient safety, it has become evident that simulation has a growing role to play in surgical education. We surveyed the program directors of 99 U.S. Neurosurgery programs in an effort to better understand how simulation can be implemented in Neurosurgery and to gain insight into key issues that are currently being discussed amongst Neurosurgical educators. A 14-item questionnaire was emailed to 99 Neurosurgery residency program directors. Questions assessed the clinical impact of simulation, the role of simulation in academia, the investments required in time and money, and the model best suited for simulation. The survey response rate was 53.5%. Seventy-two percent of respondents believed that simulation would improve patient outcome, 74% that it could supplement conventional training, but only 25% that it could replace it. The majority strongly believed that it could help preparing complex cases and could be of use to attending faculty. Forty-five percent thought that residents should achieve pre-defined levels of proficiency on simulators before working on patients. Seventy-four percent of respondents declared they would make simulator practice mandatory if available, and the majority was willing to invest daily time and considerable funds on simulators. Cadavers were the least preferred models to use compared to virtual simulation and noncadaveric physical models. Simulation should be integrated in Neurosurgery training curricula. The validation of available tools is the next step that will enable the training, acquisition, and testing of neurosurgical skills. Copyright © 2013 Elsevier Inc. All rights reserved.

Student perception of two different simulation techniques in oral and maxillofacial surgery undergraduate training.

PubMed

Lund, Bodil; Fors, Uno; Sejersen, Ronny; Sallnäs, Eva-Lotta; Rosén, Annika

2011-10-12

Yearly surveys among the undergraduate students in oral and maxillofacial surgery at Karolinska Institutet have conveyed a wish for increased clinical training, and in particular, in surgical removal of mandibular third molars. Due to lack of resources, this kind of clinical supervision has so far not been possible to implement. One possible solution to this problem might be to introduce simulation into the curriculum. The purpose of this study was to investigate undergraduate students' perception of two different simulation methods for practicing clinical reasoning skills and technical skills in oral and maxillofacial surgery. Forty-seven students participating in the oral and maxillofacial surgery course at Karolinska Institutet during their final year were included. Three different oral surgery patient cases were created in a Virtual Patient (VP) Simulation system (Web-SP) and used for training clinical reasoning. A mandibular third molar surgery simulator with tactile feedback, providing hands on training in the bone removal and tooth sectioning in third molar surgery, was also tested. A seminar was performed using the combination of these two simulators where students' perception of the two different simulation methods was assessed by means of a questionnaire. The response rate was 91.5% (43/47). The students were positive to the VP cases, although they rated their possible improvement of clinical reasoning skills as moderate. The students' perception of improved technical skills after training in the mandibular third molar surgery simulator was rated high. The majority of the students agreed that both simulation techniques should be included in the curriculum and strongly agreed that it was a good idea to use the two simulators in concert. The importance of feedback from the senior experts during simulator training was emphasised. The two tested simulation methods were well accepted and most students agreed that the future curriculum would benefit from permanent inclusion of these exercises, especially when used in combination. The results also stress the importance of teaching technical skills and clinical reasoning in concert.

Effectiveness of a Web-Based Simulation in Improving Nurses' Workplace Practice With Deteriorating Ward Patients: A Pre- and Postintervention Study.

PubMed

Liaw, Sok Ying; Wong, Lai Fun; Lim, Eunice Ya Ping; Ang, Sophia Bee Leng; Mujumdar, Sandhya; Ho, Jasmine Tze Yin; Mordiffi, Siti Zubaidah; Ang, Emily Neo Kim

2016-02-19

Nurses play an important role in detecting patients with clinical deterioration. However, the problem of nurses failing to trigger deteriorating ward patients still persists despite the implementation of a patient safety initiative, the Rapid Response System. A Web-based simulation was developed to enhance nurses' role in recognizing and responding to deteriorating patients. While studies have evaluated the effectiveness of the Web-based simulation on nurses' clinical performance in a simulated environment, no study has examined its impact on nurses' actual practice in the clinical setting. The objective of this study was to evaluate the impact of Web-based simulation on nurses' recognition of and response to deteriorating patients in clinical settings. The outcomes were measured across all levels of Kirkpatrick's 4-level evaluation model with clinical outcome on triggering rates of deteriorating patients as the primary outcome measure. A before-and-after study was conducted on two general wards at an acute care tertiary hospital over a 14-month period. All nurses from the two study wards who undertook the Web-based simulation as part of their continuing nursing education were invited to complete questionnaires at various time points to measure their motivational reaction, knowledge, and perceived transfer of learning. Clinical records on cases triggered by ward nurses from the two study wards were evaluated for frequency and types of triggers over a period of 6 months pre- and 6 months postintervention. The number of deteriorating patients triggered by ward nurses in a medical general ward increased significantly (P<.001) from pre- (84/937, 8.96%) to postintervention (91/624, 14.58%). The nurses reported positively on the transfer of learning (mean 3.89, SD 0.49) from the Web-based simulation to clinical practice. A significant increase (P<.001) on knowledge posttest score from pretest score was also reported. The nurses also perceived positively their motivation (mean 3.78, SD 0.56) to engage in the Web-based simulation. This study provides evidence on the effectiveness of Web-based simulation in improving nursing practice when recognizing and responding to deteriorating patients. This educational tool could be implemented by nurse educators worldwide to address the educational needs of a large group of hospital nurses responsible for patients in clinical deterioration.

Sport simulation as a form of implicit motor training in a geriatric athlete after stroke: a case report.

PubMed

Young, Sonia N; VanWye, William R; Wallmann, Harvey W

2018-06-25

To describe the use of sport simulation activities as a form of implicit motor learning training with a geriatric former athlete following a stroke. An active 76-year-old former professional male softball player presented to outpatient physical therapy with medical history of right stroke with left hemiparesis 2 weeks following onset of symptoms of impaired balance, coordination, gait, and motor planning. Initial physical therapy included gait, balance, and coordination training. Additional sport-related balance and coordination activities were later added to the treatment plan. After approximately 3 weeks of treatment, the patient was able to return to work and had dramatically improved balance, coordination, and gait with sport simulation activities. Implicit motor learning techniques were incorporated through sport and job task simulation activities along with task-oriented neuromuscular reeducation. The patient demonstrated improvements with gait, balance, gross motor function, and decreased fall risk.

[Simulation in surgical training].

PubMed

Nabavi, A; Schipper, J

2017-01-01

Patient safety during operations hinges on the surgeon's skills and abilities. However, surgical training has come under a variety of restrictions. To acquire dexterity with decreasingly "simple" cases, within the legislative time constraints and increasing expectations for surgical results is the future challenge. Are there alternatives to traditional master-apprentice learning? A literature review and analysis of the development, implementation, and evaluation of surgical simulation are presented. Simulation, using a variety of methods, most important physical and virtual (computer-generated) models, provides a safe environment to practice basic and advanced skills without endangering patients. These environments have specific strengths and weaknesses. Simulations can only serve to decrease the slope of learning curves, but cannot be a substitute for the real situation. Thus, they have to be an integral part of a comprehensive training curriculum. Our surgical societies have to take up that challenge to ensure the training of future generations.

Effect of clinical decision rules, patient cost and malpractice information on clinician brain CT image ordering: a randomized controlled trial.

PubMed

Gimbel, Ronald W; Pirrallo, Ronald G; Lowe, Steven C; Wright, David W; Zhang, Lu; Woo, Min-Jae; Fontelo, Paul; Liu, Fang; Connor, Zachary

2018-03-12

The frequency of head computed tomography (CT) imaging for mild head trauma patients has raised safety and cost concerns. Validated clinical decision rules exist in the published literature and on-line sources to guide medical image ordering but are often not used by emergency department (ED) clinicians. Using simulation, we explored whether the presentation of a clinical decision rule (i.e. Canadian CT Head Rule - CCHR), findings from malpractice cases related to clinicians not ordering CT imaging in mild head trauma cases, and estimated patient out-of-pocket cost might influence clinician brain CT ordering. Understanding what type and how information may influence clinical decision making in the ordering advanced medical imaging is important in shaping the optimal design and implementation of related clinical decision support systems. Multi-center, double-blinded simulation-based randomized controlled trial. Following standardized clinical vignette presentation, clinicians made an initial imaging decision for the patient. This was followed by additional information on decision support rules, malpractice outcome review, and patient cost; each with opportunity to modify their initial order. The malpractice and cost information differed by assigned group to test the any temporal relationship. The simulation closed with a second vignette and an imaging decision. One hundred sixteen of the 167 participants (66.9%) initially ordered a brain CT scan. After CCHR presentation, the number of clinicians ordering a CT dropped to 76 (45.8%), representing a 21.1% reduction in CT ordering (P = 0.002). This reduction in CT ordering was maintained, in comparison to initial imaging orders, when presented with malpractice review information (p = 0.002) and patient cost information (p = 0.002). About 57% of clinicians changed their order during study, while 43% never modified their imaging order. This study suggests that ED clinician brain CT imaging decisions may be influenced by clinical decision support rules, patient out-of-pocket cost information and findings from malpractice case review. NCT03449862 , February 27, 2018, Retrospectively registered.

Evaluating the Difference between Virtual and Paper-Based Clinical Cases in Family Medicine Undergraduate Education

PubMed Central

Cagran, Branka

2018-01-01

Introduction A “virtual patient” is defined as a computer program which simulates real patients' cases. The aim of this study was to determine whether the inclusion of virtual patients affects the level of factual knowledge of family medicine students at the undergraduate level. Methods This was a case-controlled prospective study. The students were randomly divided into experimental (EG: N = 51) and control (CG: N = 48) groups. The students in the EG were asked to practice diagnosis using virtual patients instead of the paper-based clinical cases which were solved by the students in the CG. The main observed variable in the study was knowledge of family medicine, determined by 50 multiple choice questions (MCQs) about knowledge of family medicine. Results There were no statistically significant differences in the groups' initial knowledge. At the final assessment of knowledge, there were no statistically significant differences between the groups, but there was a statistically significant difference between their initial and final knowledge. Conclusions The study showed that adding virtual patient cases to the curriculum, instead of paper clinical cases, did not affect the level of factual knowledge about family medicine. Virtual patients can be used, but a significant educational outcome is not expected. PMID:29568779

Development of an algorithm to plan and simulate a new interventional procedure.

PubMed

Fujita, Buntaro; Kütting, Maximilian; Scholtz, Smita; Utzenrath, Marc; Hakim-Meibodi, Kavous; Paluszkiewicz, Lech; Schmitz, Christoph; Börgermann, Jochen; Gummert, Jan; Steinseifer, Ulrich; Ensminger, Stephan

2015-07-01

The number of implanted biological valves for treatment of valvular heart disease is growing and a percentage of these patients will eventually undergo a transcatheter valve-in-valve (ViV) procedure. Some of these patients will represent challenging cases. The aim of this study was to develop a feasible algorithm to plan and in vitro simulate a new interventional procedure to improve patient outcome. In addition to standard diagnostic routine, our algorithm includes 3D printing of the annulus, hydrodynamic measurements and high-speed analysis of leaflet kinematics after simulation of the procedure in different prosthesis positions as well as X-ray imaging of the most suitable valve position to create a 'blueprint' for the patient procedure. This algorithm was developed for a patient with a degenerated Perceval aortic sutureless prosthesis requiring a ViV procedure. Different ViV procedures were assessed in the algorithm and based on these results the best option for the patient was chosen. The actual procedure went exactly as planned with help of this algorithm. Here we have developed a new technically feasible algorithm simulating important aspects of a novel interventional procedure prior to the actual procedure. This algorithm can be applied to virtually all patients requiring a novel interventional procedure to help identify risks and find optimal parameters for prosthesis selection and placement in order to maximize safety for the patient. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Improving client satisfaction and clinic revenues through systems simulation: the case of a university nutrition clinic.

PubMed

Thompson, R C; Scammon, D L

1994-01-01

A client-responsive strategy was developed based upon input from nutrition clinic personnel, administrators, and clients. Systems simulation identified the strategy most likely to lead to client satisfaction while also meeting the needs of clinic personnel and administration. The strategy was subsequently introduced into the clinic and patient satisfaction and operating revenues were monitored following implementation. Both measures of impact demonstrated significant improvement.

The Impact of Oral-Systemic Health on Advancing Interprofessional Education Outcomes.

PubMed

Haber, Judith; Hartnett, Erin; Allen, Kenneth; Crowe, Ruth; Adams, Jennifer; Bella, Abigail; Riles, Thomas; Vasilyeva, Anna

2017-02-01

The aim of this study was to evaluate the effectiveness of an interprofessional education (IPE) clinical simulation and case study experience, using oral-systemic health as the clinical population health example, for nurse practitioner/midwifery, dental, and medical students' self-reported attainment of interprofessional competencies. A pretest-posttest evaluation method was employed, using data from the Interprofessional Collaborative Competency Attainment Scale (ICCAS) completed by two large cohorts of nurse practitioner/midwifery, dental, and medical students at one U.S. university. Data from faculty facilitators were collected to assess their perceptions of the value of exposing students to interprofessional clinical simulation experiences focused on oral-systemic health. The results showed that self-reported interprofessional competencies measured by the ICCAS improved significantly from pre- to posttest for all three student types in 2013 (p<0.001) and 2014 (p<0.001). Faculty facilitators reported that the IPE clinical simulation experiences were valuable and positively influenced interprofessional communication, collaboration, patient communication, and student understanding of patient care roles. These results suggest that the Teaching Oral-Systemic Health Program Interprofessional Oral-Systemic Health Clinical Simulation and Case Study Experience was effective as a standardized, replicable curriculum unit using oral-systemic health as a population health exemplar to teach and assess interprofessional competencies with nurse practitioner/midwifery, dental, and medical students.

Development of three-dimensional hollow elastic model for cerebral aneurysm clipping simulation enabling rapid and low cost prototyping.

PubMed

Mashiko, Toshihiro; Otani, Keisuke; Kawano, Ryutaro; Konno, Takehiko; Kaneko, Naoki; Ito, Yumiko; Watanabe, Eiju

2015-03-01

We developed a method for fabricating a three-dimensional hollow and elastic aneurysm model useful for surgical simulation and surgical training. In this article, we explain the hollow elastic model prototyping method and report on the effects of applying it to presurgical simulation and surgical training. A three-dimensional printer using acrylonitrile-butadiene-styrene as a modeling material was used to produce a vessel model. The prototype was then coated with liquid silicone. After the silicone had hardened, the acrylonitrile-butadiene-styrene was melted with xylene and removed, leaving an outer layer as a hollow elastic model. Simulations using the hollow elastic model were performed in 12 patients. In all patients, the clipping proceeded as scheduled. The surgeon's postoperative assessment was favorable in all cases. This method enables easy fabrication at low cost. Simulation using the hollow elastic model is thought to be useful for understanding of three-dimensional aneurysm structure. Copyright © 2015 Elsevier Inc. All rights reserved.

The impact of the difference in O-C2 angle in the development of dysphagia after occipitocervical fusion: a simulation study in normal volunteers combined with a case-control study.

PubMed

Meng, Yang; Wu, Tingkui; Liu, Ziyang; Wen, Daguang; Rong, Xin; Chen, Hua; Lou, Jigang; Liu, Hao

2018-02-02

Dysphagia has been recognized as one of the most serious complications after occipitocervical fusion (OCF), and the difference between postoperative and preoperative O-C2 angle (dO-C2A) was proposed to be an indicator in predicting and preventing dysphagia. Therefore, to prevent postoperative dysphagia, previous studies recommend that surgeons should correct the O-C2 angle (O-C2A) during surgery if the occipitocervical alignment was in an excessively flexed position. However, until now, there was no explicit indicator of the condition in which surgeons should adjust the patient's O-C2A during surgery. One of the purposes of this study was to explore the threshold of dO-C2A between dysphagia and normal swallowing by a simulation study. The other aim was to evaluate the validity of the threshold of dO-C2A in predicting dysphagia after OCF via a case-control study. This is a simulation study combined with a retrospective case-control study. Thirty volunteers were enrolled in the simulation study. Thirty-four consecutive patients who underwent OCF between September 2011 and September 2016 were included in the case-control study. The outcome measures included O-C2A, C2-7 angle (C2-7A), atlantodental interval (ADI), the narrowest oropharyngeal airway space (nPAS), the rate of change in dnPAS (%dnPAS), and the prevalence of postoperative dysphagia. In the simulation study, each volunteer received two lateral x-rays of their cervical spine in neutral position and dysphagia position, respectively. We compared the radiographic parameters in neutral and dysphagia positions. The cumulative frequency diagram of dO-C2A in the dysphagia position was analyzed to identify the threshold of dO-C2A in the development of dysphagia. In the case-control study, these 34 patients were divided into two groups according to the threshold of dO-C2A identified in the simulation study. The impact of radiographic parameters on nPAS was analyzed. The prevalence of postoperative dysphagia between the two groups was compared to evaluate the validity of the threshold of dO-C2A in predicting dysphagia after OCF. In the simulation study, the mean O-C2A and nPAS in the dysphagia position were significantly smaller than in the neutral position (p<.05). There was no significant difference between the mean C2-7A in the neutral and dysphagia positions (p>.05). There was a significant positive correlation between dO-C2A and dnPAS (p<.05). A dO-C2A of -5° delineated the threshold between normal swallowing and dysphagia. In the case-control study, multiple regression analysis showed that dO-C2A was the only significant variable correlated with dnPAS (β=0.769, p<.001). Among the reviewed 34 patients, the incidence of dysphagia was 17.6% (6/34) at 2 weeks after surgery and decreased over time to 11.8% (4 of 34) at the last follow-up. There was also a significant positive correlation between the dO-C2A and dnPAS (p<.05). The prevalence of dysphagia after OCF in patients with dO-C2A<-5° was as high as 66.7% (6/9). However, there was no patient suffering from dysphagia in patients with dO-C2A≥-5°. The present study showed that the dO-C2A should be a key factor in the development of postoperative dysphagia after OCF. A dO-C2A of -5° could be the threshold between dysphagia and normal swallowing. Furthermore, to avoid dysphagia, surgeons should correct the O-C2A just before the final occipitocervical fixation if the checked dO-C2A during surgery is less than -5°. Copyright © 2018 Elsevier Inc. All rights reserved.

A Motion Simulator Ride Associated With Headache and Subdural Hematoma: First Case Report.

PubMed

Scranton, Robert A; Evans, Randolph W; Baskin, David S

2016-02-01

We report the first case report of symptomatic bilateral subdural hematomas (SDH) associated with riding a centrifugal motion simulator ride. A previously healthy 55-year-old male developed new onset daily headaches 1 week after going on the ride that were due to symptomatic bilateral SDH requiring operative intervention with a full recovery. There was no history of other trauma or other systemic or intracranial abnormality to account for the development of the SDH. We review the headaches and other clinical features associated with chronic SDH. Twelve cases of roller coaster headaches due to SDH associated with riding roller coasters have been reported. The pathophysiology is reviewed, which we believe is the same mechanism that may be responsible in this case. Although it is possible that this neurovascular injury is truly rare, it is also possible that this injury is underreported as patients and physicians may not make the association or physicians have not reported additional cases. The risk of this injury likely increases with age, as the size of the subdural space increases, and may support the maxim that "roller coasters and simulators are for kids." © 2015 American Headache Society.

Dosimetric investigation of proton therapy on CT-based patient data using Monte Carlo simulation

NASA Astrophysics Data System (ADS)

Chongsan, T.; Liamsuwan, T.; Tangboonduangjit, P.

2016-03-01

The aim of radiotherapy is to deliver high radiation dose to the tumor with low radiation dose to healthy tissues. Protons have Bragg peaks that give high radiation dose to the tumor but low exit dose or dose tail. Therefore, proton therapy is promising for treating deep- seated tumors and tumors locating close to organs at risk. Moreover, the physical characteristic of protons is suitable for treating cancer in pediatric patients. This work developed a computational platform for calculating proton dose distribution using the Monte Carlo (MC) technique and patient's anatomical data. The studied case is a pediatric patient with a primary brain tumor. PHITS will be used for MC simulation. Therefore, patient-specific CT-DICOM files were converted to the PHITS input. A MATLAB optimization program was developed to create a beam delivery control file for this study. The optimization program requires the proton beam data. All these data were calculated in this work using analytical formulas and the calculation accuracy was tested, before the beam delivery control file is used for MC simulation. This study will be useful for researchers aiming to investigate proton dose distribution in patients but do not have access to proton therapy machines.

Isolated laryngeal leishmaniasis in an immunocompetent patient: a case report.

PubMed

Bajraktari, A; Seccia, V; Casani, A P; Franceschini, S S

Isolated laryngeal leishmaniasis in an immunocompetent patient: a case report. Isolated laryngeal Leishmaniasis presents neither explicit laryngeal lesions nor specific symptoms. In fact, it may mimic many inflammatory and neoplastic diseases. Considering the low incidence of this atypical localization, laryngeal Leishmaniasis, is rarely contemplated by physicians in differential diagnoses of laryngeal tumour lesions. We present the case of a 62-year-old immunocompetent subject who developed a single Leishmania mucosal lesion on the left vocal cord, simulating a laryngeal cancer. A case report and discussion of the clinical case by referring to the literature. Specific therapy with miltefosine led to clinical and endoscopic improvement. We had no relapse after three years of follow-up. This clinical case highlights the need to consider isolated laryngeal Leishmaniasis in the differential diagnoses of laryngeal tumour lesions, even in immunocompetent subjects who live in endemic zones, in order to ensure an early and correct therapeutic approach.

Inter-Identity Autobiographical Amnesia in Patients with Dissociative Identity Disorder

PubMed Central

Huntjens, Rafaële J. C.; Verschuere, Bruno; McNally, Richard J.

2012-01-01

Background A major symptom of Dissociative Identity Disorder (DID; formerly Multiple Personality Disorder) is dissociative amnesia, the inability to recall important personal information. Only two case studies have directly addressed autobiographical memory in DID. Both provided evidence suggestive of dissociative amnesia. The aim of the current study was to objectively assess transfer of autobiographical information between identities in a larger sample of DID patients. Methods Using a concealed information task, we assessed recognition of autobiographical details in an amnesic identity. Eleven DID patients, 27 normal controls, and 23 controls simulating DID participated. Controls and simulators were matched to patients on age, education level, and type of autobiographical memory tested. Findings Although patients subjectively reported amnesia for the autobiographical details included in the task, the results indicated transfer of information between identities. Conclusion The results call for a revision of the DID definition. The amnesia criterion should be modified to emphasize its subjective nature. PMID:22815769

Inter-identity autobiographical amnesia in patients with dissociative identity disorder.

PubMed

Huntjens, Rafaële J C; Verschuere, Bruno; McNally, Richard J

2012-01-01

A major symptom of Dissociative Identity Disorder (DID; formerly Multiple Personality Disorder) is dissociative amnesia, the inability to recall important personal information. Only two case studies have directly addressed autobiographical memory in DID. Both provided evidence suggestive of dissociative amnesia. The aim of the current study was to objectively assess transfer of autobiographical information between identities in a larger sample of DID patients. Using a concealed information task, we assessed recognition of autobiographical details in an amnesic identity. Eleven DID patients, 27 normal controls, and 23 controls simulating DID participated. Controls and simulators were matched to patients on age, education level, and type of autobiographical memory tested. Although patients subjectively reported amnesia for the autobiographical details included in the task, the results indicated transfer of information between identities. The results call for a revision of the DID definition. The amnesia criterion should be modified to emphasize its subjective nature.

Simulating patient-specific heart shape and motion using SPECT perfusion images with the MCAT phantom

NASA Astrophysics Data System (ADS)

Faber, Tracy L.; Garcia, Ernest V.; Lalush, David S.; Segars, W. Paul; Tsui, Benjamin M.

2001-05-01

The spline-based Mathematical Cardiac Torso (MCAT) phantom is a realistic software simulation designed to simulate single photon emission computed tomographic (SPECT) data. It incorporates a heart model of known size and shape; thus, it is invaluable for measuring accuracy of acquisition, reconstruction, and post-processing routines. New functionality has been added by replacing the standard heart model with left ventricular (LV) epicaridal and endocardial surface points detected from actual patient SPECT perfusion studies. LV surfaces detected from standard post-processing quantitation programs are converted through interpolation in space and time into new B-spline models. Perfusion abnormalities are added to the model based on results of standard perfusion quantification. The new LV is translated and rotated to fit within existing atria and right ventricular models, which are scaled based on the size of the LV. Simulations were created for five different patients with myocardial infractions who had undergone SPECT perfusion imaging. Shape, size, and motion of the resulting activity map were compared visually to the original SPECT images. In all cases, size, shape and motion of simulated LVs matched well with the original images. Thus, realistic simulations with known physiologic and functional parameters can be created for evaluating efficacy of processing algorithms.

Preoperative easily misdiagnosed telangiectatic osteosarcoma: clinical-radiologic-pathologic correlations.

PubMed

Gao, Zhen-Hua; Yin, Jun-Qiang; Liu, Da-Wei; Meng, Quan-Fei; Li, Jia-Ping

2013-12-11

To describe the clinical, imaging, and pathologic characteristics and diagnostic methods of telangiectatic osteosarcoma (TOS) for improving the diagnostic level. The authors retrospectively reviewed patient demographics, serum alkaline phosphatase (AKP) levels, preoperative biopsy pathologic reports, pathologic materials, imaging findings, and treatment outcomes from 26 patients with TOS. Patient images from radiography (26 cases) and magnetic resonance (MR) imaging (22 cases) were evaluated by 3 authors in consensus for intrinsic characteristics. There were 15 male and 11 female patients in the study, with an age of 9-32 years (mean age 15.9 years). Eighteen of 26 patients died of lung metastases within 5 years of follow-up. The distal femur was affected more commonly (14 cases, 53.8%). Regarding serum AKP, normal (8 cases) or mildly elevated (18 cases) levels were found before preoperative chemotherapy. Radiographs showed geographic bone lysis without sclerotic margin (26 cases), cortical destruction (26 cases), periosteal new bone formation (24 cases), soft-tissue mass (23 cases), and matrix mineralization (4 cases). The aggressive radiographic features of TOS simulated the appearance of conventional high-grade intramedullary osteosarcoma, though different from aneurysmal bone cyst. MR images demonstrated multiple big (16 cases) or small (6 cases) cystic spaces, fluid-fluid levels (14 cases), soft-tissue mass (22 cases), and thick peripheral and septal enhancement (22 cases). Nine of 26 cases were misdiagnosed as aneurysmal bone cysts by preoperative core-needle biopsy, owing to the absence of viable high-grade sarcomatous cells in the small tissue samples. The aggressive growth pattern with occasional matrix mineralization, and multiple big or small fluid-filled cavities with thick peripheral, septal, and nodular tissue surrounding the fluid-filled cavities are characteristic imaging features of TOS, and these features are helpful in making the correct preoperative diagnosis of TOS.

Fuzzy Naive Bayesian model for medical diagnostic decision support.

PubMed

Wagholikar, Kavishwar B; Vijayraghavan, Sundararajan; Deshpande, Ashok W

2009-01-01

This work relates to the development of computational algorithms to provide decision support to physicians. The authors propose a Fuzzy Naive Bayesian (FNB) model for medical diagnosis, which extends the Fuzzy Bayesian approach proposed by Okuda. A physician's interview based method is described to define a orthogonal fuzzy symptom information system, required to apply the model. For the purpose of elaboration and elicitation of characteristics, the algorithm is applied to a simple simulated dataset, and compared with conventional Naive Bayes (NB) approach. As a preliminary evaluation of FNB in real world scenario, the comparison is repeated on a real fuzzy dataset of 81 patients diagnosed with infectious diseases. The case study on simulated dataset elucidates that FNB can be optimal over NB for diagnosing patients with imprecise-fuzzy information, on account of the following characteristics - 1) it can model the information that, values of some attributes are semantically closer than values of other attributes, and 2) it offers a mechanism to temper exaggerations in patient information. Although the algorithm requires precise training data, its utility for fuzzy training data is argued for. This is supported by the case study on infectious disease dataset, which indicates optimality of FNB over NB for the infectious disease domain. Further case studies on large datasets are required to establish utility of FNB.

Using simulation to isolate physician variation in intensive care unit admission decision making for critically ill elders with end-stage cancer: a pilot feasibility study.

PubMed

Barnato, Amber E; Hsu, Heather E; Bryce, Cindy L; Lave, Judith R; Emlet, Lillian L; Angus, Derek C; Arnold, Robert M

2008-12-01

To determine the feasibility of high-fidelity simulation for studying variation in intensive care unit admission decision making for critically ill elders with end-stage cancer. Mixed qualitative and quantitative analysis of physician subjects participating in a simulation scenario using hospital set, actors, medical chart, and vital signs tracings. The simulation depicted a 78-yr-old man with metastatic gastric cancer, life-threatening hypoxia most likely attributable to cancer progression, and stable preferences to avoid intensive care unit admission and intubation. Two independent raters assessed the simulations and subjects completed a postsimulation web-based survey and debriefing interview. Peter M. Winter Institute for Simulation Education and Research at the University of Pittsburgh. Twenty-seven hospital-based attending physicians, including 6 emergency physicians, 13 hospitalists, and 8 intensivists. Outcomes included qualitative report of clinical verisimilitude during the debriefing interview, survey-reported diagnosis and prognosis, and observed treatment decisions. Independent variables included physician demographics, risk attitude, and reactions to uncertainty. All (100%) reported that the case and simulation were highly realistic, and their diagnostic and prognostic assessments were consistent with our intent. Eight physicians (29.6%) admitted the patient to the intensive care unit. Among the eight physicians who admitted the patient to the intensive care unit, three (37%) initiated palliation, two (25%) documented the patient's code status (do not intubate/do not resuscitate), and one intubated the patient. Among the 19 physicians who did not admit the patient to the intensive care unit, 13 (68%) initiated palliation and 5 (42%) documented code status. Intensivists and emergency physicians (p = 0.048) were more likely to admit the patient to the intensive care unit. Years since medical school graduation were inversely associated with the initiation of palliative care (p = 0.043). Simulation can reproduce the decision context of intensive care unit triage for a critically ill patient with terminal illness. When faced with an identical patient, hospital-based physicians from the same institution vary significantly in their treatment decisions.

Simulated Patient Studies: An Ethical Analysis

PubMed Central

Rhodes, Karin V; Miller, Franklin G

2012-01-01

Context In connection with health care reform, the U.S. Department of Health and Human Services commissioned a “mystery shopper,” or simulated patient study, to measure access to primary care. But the study was shelved because of public controversy over “government spying” on doctors. Opponents of the study also raised ethical concerns about the use of deception with human subjects without soliciting their informed consent. Methods We undertook an ethical analysis of the use of simulated patient techniques in health services research, with a particular focus on research measuring access to care. Using a case study, we explored relevant methodological considerations and ethical principles relating to deceptive research without informed consent, as well as U.S. federal regulations permitting exceptions to consent. Findings Several relevant considerations both favor and oppose soliciting consent for simulated patient studies. Making research participation conditional on informed consent protects the autonomy of research subjects and shields them from unreasonable exposure to research risks. However, scientific validity is also an important ethical principle of human subjects research, as the net risks to subjects must be justified by the value to society of the knowledge to be gained. The use of simulated patients to monitor access is a naturalistic and scientifically sound experimental design that can answer important policy-relevant questions, with minimal risks to human subjects. As interaction between researchers and subjects increases, however, so does the need for consent. Conclusions As long as adequate protections of confidentiality of research data are in place, minimally intrusive simulated patient research that gathers policy-relevant data on the health system without the consent of individuals working in that system can be ethically justified when the risks and burdens to research subjects are minimal and the research has the potential to generate socially valuable knowledge. PMID:23216428

SU-D-BRD-06: Automated Population-Based Planning for Whole Brain Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schreibmann, E; Fox, T; Crocker, I

2014-06-01

Purpose: Treatment planning for whole brain radiation treatment is technically a simple process but in practice it takes valuable clinical time of repetitive and tedious tasks. This report presents a method that automatically segments the relevant target and normal tissues and creates a treatment plan in only a few minutes after patient simulation. Methods: Segmentation is performed automatically through morphological operations on the soft tissue. The treatment plan is generated by searching a database of previous cases for patients with similar anatomy. In this search, each database case is ranked in terms of similarity using a customized metric designed formore » sensitivity by including only geometrical changes that affect the dose distribution. The database case with the best match is automatically modified to replace relevant patient info and isocenter position while maintaining original beam and MLC settings. Results: Fifteen patients were used to validate the method. In each of these cases the anatomy was accurately segmented to mean Dice coefficients of 0.970 ± 0.008 for the brain, 0.846 ± 0.009 for the eyes and 0.672 ± 0.111 for the lens as compared to clinical segmentations. Each case was then subsequently matched against a database of 70 validated treatment plans and the best matching plan (termed auto-planned), was compared retrospectively with the clinical plans in terms of brain coverage and maximum doses to critical structures. Maximum doses were reduced by a maximum of 20.809 Gy for the left eye (mean 3.533), by 13.352 (1.311) for the right eye, and by 27.471 (4.856), 25.218 (6.315) for the left and right lens. Time from simulation to auto-plan was 3-4 minutes. Conclusion: Automated database- based matching is an alternative to classical treatment planning that improves quality while providing a cost—effective solution to planning through modifying previous validated plans to match a current patient's anatomy.« less

A Comparison of Educational Interventions to Enhance Cultural Competency in Pharmacy Students

PubMed Central

Jonkman, Lauren; Connor, Sharon; Hall, Deanne

2013-01-01

Objective. To determine the degree to which 3 different educational interventions enhance cultural competency in pharmacy students. Methods. Students were equally divided among a simulated-patient activity group, a written case-scenarios group, and a formal lecture group. Mean scores for pre- and post-intervention cultural self-assessment surveys were compared. Results. In the simulation group, there were significant positive changes in the cultural skills and cultural desire components; in the case-scenario group, there was a significant positive change in the cultural awareness component; and in the lecture group, there were significant positive changes in the cultural skills and cultural empathy components. With respect to the cultural skills component, there was greater post-intervention improvement in the simulation and lecture groups than in the case-scenario group. Conclusions. There were significant positive changes within each group, indicating that ideologies and behaviors may be altered based on the educational intervention received. However, a 1-hour practicum may not be sufficient to enhance cultural competency. PMID:23716744

Modeling Test and Treatment Strategies for Presymptomatic Alzheimer Disease

PubMed Central

Burke, James F.; Langa, Kenneth M.; Hayward, Rodney A.; Albin, Roger L.

2014-01-01

Objectives In this study, we developed a model of presymptomatic treatment of Alzheimer disease (AD) after a screening diagnostic evaluation and explored the circumstances required for an AD prevention treatment to produce aggregate net population benefit. Methods Monte Carlo simulation methods were used to estimate outcomes in a simulated population derived from data on AD incidence and mortality. A wide variety of treatment parameters were explored. Net population benefit was estimated in aggregated QALYs. Sensitivity analyses were performed by individually varying the primary parameters. Findings In the base-case scenario, treatment effects were uniformly positive, and net benefits increased with increasing age at screening. A highly efficacious treatment (i.e. relative risk 0.6) modeled in the base-case is estimated to save 20 QALYs per 1000 patients screened and 221 QALYs per 1000 patients treated. Conclusions Highly efficacious presymptomatic screen and treat strategies for AD are likely to produce substantial aggregate population benefits that are likely greater than the benefits of aspirin in primary prevention of moderate risk cardiovascular disease (28 QALYS per 1000 patients treated), even in the context of an imperfect treatment delivery environment. PMID:25474698

[Tuberculous pseudotumour, a challenging diagnosis].

PubMed

Snene, H; Ben Mansour, A; Toujani, S; Ben Salah, N; Mjid, M; Ouahchi, Y; Mehiri, N; Beji, M; Cherif, J; Louzir, B

2018-03-01

The pseudotumorous form of tuberculosis is a rare entity. Whatever its location, it can simulate neoplasia by its radiological and/or endoscopic appearances. We highlight the diagnostic difficulties associated with this type of presentation. We performed a retrospective study of inpatient records from 2003 to 2016 in the pneumology department of La Rabta Hospital to identify cases of thoracic tuberculous pseudo-tumor. Seventeen patients were identified. The median age was 41 years and their symptomatology was dominated by cough and general debility. All had abnormal radiology with 10 cases of suspect lesions. Fibre-optic bronchoscopy revealed endobronchial abnormalities in 11 cases. The median overall diagnostic delay was 97 days. The diagnosis was confirmed bacteriologically in five cases, histologically in 14 cases and based on clinical presumption in one case. The progression was favourable: 13 patients have been declared cured and four patients are still undergoing treatment. Making a positive diagnosis of thoracic tuberculous pseudotumour can be difficult, as bacteriological samples are often negative. This can lead to a significant delay in diagnosis and treatment. Copyright © 2017 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Multiple hepatic lesions in a case of isolated hepatic tuberculosis simulating metastases on 18F-FDG PET/CT imaging.

PubMed

Karunanithi, Sellam; Sharma, Punit; Jain, Tarun Kumar; Vijay, Maneesh Kumar; Kumar, Rakesh

2014-01-01

Hepatic tuberculosis is an unusual form of extrapulmonary tuberculosis and constitutes less than 1% of all cases of tuberculosis. Imaging studies for hepatic tuberculosis are nonspecific and mimic primary or metastatic carcinoma. Here we present ¹⁸F-FDG PET/CT images of a 25-year-old male patient with isolated hepatic tuberculosis.

Three-dimensional analysis of the respiratory interplay effect in helical tomotherapy: Baseline variations cause the greater part of dose inhomogeneities seen.

PubMed

Tudor, G Samuel J; Harden, Susan V; Thomas, Simon J

2014-03-01

Dose differences from those planned can occur due to the respiratory interplay effect on helical tomotherapy. The authors present a technique to calculate single-fraction doses in three-dimensions resulting from craniocaudal motion applied to a patient CT set. The technique is applied to phantom and patient plans using patient respiratory traces. An additional purpose of the work is to determine the contribution toward the interplay effect of different components of the respiratory trace. MATLAB code used to calculate doses to a CT dataset from a helical tomotherapy plan has been modified to permit craniocaudal motion and improved temporal resolution. Real patient traces from seven patients were applied to ten phantom plans of differing field width, modulation factor, pitch and fraction dose, and simulations made with peak-to-peak amplitudes ranging from 0 to 2.5 cm. PTV voxels near the superior or inferior limits of the PTV are excluded from the analysis. The maximum dose discrepancy compared with the static case recorded along with the proportion of voxels receiving more than 10% and 20% different from prescription dose. The analysis was repeated with the baseline variation of the respiratory trace removed, leaving the cyclic component of motion only. Radiochromic film was used on one plan-trace combination and compared with the software simulation. For one case, filtered traces were generated and used in simulations which consisted only of frequencies near to particular characteristic frequencies of the treatment delivery. Intraslice standard deviation of dose differences was used to identify potential MLC interplay, which was confirmed using nonmodulated simulations. Software calculations were also conducted for four realistic patient plans and modeling movement of a patient CT set with amplitudes informed by the observed motion of the GTV on 4DCT. The maximum magnitude of dose difference to a PTV voxel due to the interplay effect within a particular plan-trace combination for peak-to-peak amplitudes of up to 2.5 cm ranged from 4.5% to 51.6% (mean: 23.8%) of the dose delivered in the absence of respiratory motion. For cyclic motion only, the maximum dose differences in each combination ranged from 2.1% to 26.2% (mean: 9.2%). There is reasonable correspondence between an example of the phantom plan simulations and radiochromic film measurement. The filtered trace simulations revealed that frequencies close to the characteristic frequency of the jaw motion across the target were found to generate greater interplay effect than frequencies close to the gantry frequency or MLC motion. There was evidence of interplay between respiratory motion and MLC modulation, but this is small compared with the interplay between respiratory motion and jaw motion. For patient-plan simulations, dose discrepancies are seen of up to 9.0% for a patient with 0.3 cm peak-to-peak respiratory amplitude and up to 17.7% for a patient with 0.9 cm peak-to-peak amplitude. These values reduced to 1.3% and 6.5%, respectively, when only cyclic motion was considered. Software has been developed to simulate craniocaudal respiratory motion in phantom and patient plans using real patient respiratory traces. Decomposition of the traces into baseline andcyclic components reveals that the large majority of the interplay effect seen with the full trace is due to baseline variation during treatment.

The impact on revenue of increasing patient volume at surgical suites with relatively high operating room utilization.

PubMed

Dexter, F; Macario, A; Lubarsky, D A

2001-05-01

We previously studied hospitals in the United States of America that are losing money despite limiting the hours that operating room (OR) staff are available to care for patients undergoing elective surgery. These hospitals routinely keep utilization relatively high to maximize revenue. We tested, using discrete-event computer simulation, whether increasing patient volume while being reimbursed less for each additional patient can reliably achieve an increase in revenue when initial adjusted OR utilization is 90%. We found that increasing the volume of referred patients by the amount expected to fill the surgical suite (100%/90%) would increase utilization by <1% for a hospital surgical suite (with longer duration cases) and 4% for an ambulatory surgery suite (with short cases). The increase in patient volume would result in longer patient waiting times for surgery and more patients leaving the surgical queue. With a 15% reduction in payment for the new patients, the increase in volume may not increase revenue and can even decrease the contribution margin for the hospital surgical suite. The implication is that for hospitals with a relatively high OR utilization, signing discounted contracts to increase patient volume by the amount expected to "fill" the OR can have the net effect of decreasing the contribution margin (i.e., profitability). Hospitals may try to attract new surgical volume by offering discounted rates. For hospitals with a relatively high operating room utilization (e.g., 90%), computer simulations predict that increasing patient volume by the amount expected to "fill" the operating room can have the net effect of decreasing contribution margin (i.e., profitability).

Clinical decision-making by midwives: managing case complexity.

PubMed

Cioffi, J; Markham, R

1997-02-01

In making clinical judgements, it is argued that midwives use 'shortcuts' or heuristics based on estimated probabilities to simplify the decision-making task. Midwives (n = 30) were given simulated patient assessment situations of high and low complexity and were required to think aloud. Analysis of verbal protocols showed that subjective probability judgements (heuristics) were used more frequently in the high than low complexity case and predominated in the last quarter of the assessment period for the high complexity case. 'Representativeness' was identified more frequently in the high than in the low case, but was the dominant heuristic in both. Reports completed after each simulation suggest that heuristics based on memory for particular conditions affect decisions. It is concluded that midwives use heuristics, derived mainly from their clinical experiences, in an attempt to save cognitive effort and to facilitate reasonably accurate decisions in the decision-making process.

[Diagnosis and treatment of pediatric anismus].

PubMed

Ding, Shu-qing; Ding, Yi-jiang; Chen, Yong-tian; Ye, Hui

2006-11-01

To explore the diagnosis and treatment methods of pediatric anismus. Twenty-nine patients with idiopathic chronic constipation, diagnosed with anismus by colon barium contrast and anorectal manometry from Nov. 2001 to Nov. 2004 in our hospital, were investigated retrospectively. This group consisted of 13 men and 16 women whose mean age was (6.7+/-4.0) years. Hirschsprung diseases were excluded from the patients by colon barium contrast and rectoanal inhibitory reflex (RAIR) examination. Normal RAIR (5-10 ml elicited) was showed on 21 cases while weakened RAIR (15-30 ml elicited) was showed on 8 cases. After the diagnosis, the patients were treated by toilet training, diet regulation and laxative for 1-2 months. 4 cases were recovered, 5 cases were improved and 20 cases were relied on glycerin suppository. Four cases, relied on glycerin suppository, underwent Lynn procedure and had good results after 5-24 months follow-up. Two cases were re-examined by anorectal manometry 3 and 6 months after surgery, the resting pressure and the high pressure zone (HPZ) decreased, but the simulation defecation reflex was still abnormal. The diagnosis of pediatric anismus relies on history of constipation, combined with anorectal manometry and colon barium contrast. Lynn procedure could be chosen for the patients unsatisfied in toilet training and other non-operative treatment.

Simulating the behavior of patients who leave a public hospital emergency department without being seen by a physician: a cellular automaton and agent-based framework.

PubMed

Yousefi, Milad; Yousefi, Moslem; Fogliatto, F S; Ferreira, R P M; Kim, J H

2018-01-11

The objective of this study was to develop an agent based modeling (ABM) framework to simulate the behavior of patients who leave a public hospital emergency department (ED) without being seen (LWBS). In doing so, the study complements computer modeling and cellular automata (CA) techniques to simulate the behavior of patients in an ED. After verifying and validating the model by comparing it with data from a real case study, the significance of four preventive policies including increasing number of triage nurses, fast-track treatment, increasing the waiting room capacity and reducing treatment time were investigated by utilizing ordinary least squares regression. After applying the preventing policies in ED, an average of 42.14% reduction in the number of patients who leave without being seen and 6.05% reduction in the average length of stay (LOS) of patients was reported. This study is the first to apply CA in an ED simulation. Comparing the average LOS before and after applying CA with actual times from emergency department information system showed an 11% improvement. The simulation results indicated that the most effective approach to reduce the rate of LWBS is applying fast-track treatment. The ABM approach represents a flexible tool that can be constructed to reflect any given environment. It is also a support system for decision-makers to assess the relative impact of control strategies.

Simulating the behavior of patients who leave a public hospital emergency department without being seen by a physician: a cellular automaton and agent-based framework

PubMed Central

Yousefi, Milad; Yousefi, Moslem; Fogliatto, F.S.; Ferreira, R.P.M.; Kim, J.H.

2018-01-01

The objective of this study was to develop an agent based modeling (ABM) framework to simulate the behavior of patients who leave a public hospital emergency department (ED) without being seen (LWBS). In doing so, the study complements computer modeling and cellular automata (CA) techniques to simulate the behavior of patients in an ED. After verifying and validating the model by comparing it with data from a real case study, the significance of four preventive policies including increasing number of triage nurses, fast-track treatment, increasing the waiting room capacity and reducing treatment time were investigated by utilizing ordinary least squares regression. After applying the preventing policies in ED, an average of 42.14% reduction in the number of patients who leave without being seen and 6.05% reduction in the average length of stay (LOS) of patients was reported. This study is the first to apply CA in an ED simulation. Comparing the average LOS before and after applying CA with actual times from emergency department information system showed an 11% improvement. The simulation results indicated that the most effective approach to reduce the rate of LWBS is applying fast-track treatment. The ABM approach represents a flexible tool that can be constructed to reflect any given environment. It is also a support system for decision-makers to assess the relative impact of control strategies. PMID:29340526

Simulation-based interpersonal communication skills training for neurosurgical residents.

PubMed

Harnof, Sagi; Hadani, Moshe; Ziv, Amitai; Berkenstadt, Haim

2013-09-01

Communication skills are an important component of the neurosurgery residency training program. We developed a simulation-based training module for neurosurgery residents in which medical, communication and ethical dilemmas are presented by role-playing actors. To assess the first national simulation-based communication skills training for neurosurgical residents. Eight scenarios covering different aspects of neurosurgery were developed by our team: (1) obtaining informed consent for an elective surgery, (2) discharge of a patient following elective surgery, (3) dealing with an unsatisfied patient, (4) delivering news of intraoperative complications, (5) delivering news of a brain tumor to parents of a 5 year old boy, (6) delivering news of brain death to a family member, (7) obtaining informed consent for urgent surgery from the grandfather of a 7 year old boy with an epidural hematoma, and (8) dealing with a case of child abuse. Fifteen neurosurgery residents from all major medical centers in Israel participated in the training. The session was recorded on video and was followed by videotaped debriefing by a senior neurosurgeon and communication expert and by feedback questionnaires. All trainees participated in two scenarios and observed another two. Participants largely agreed that the actors simulating patients represented real patients and family members and that the videotaped debriefing contributed to the teaching of professional skills. Simulation-based communication skill training is effective, and together with thorough debriefing is an excellent learning and practical method for imparting communication skills to neurosurgery residents. Such simulation-based training will ultimately be part of the national residency program.

Assessing cardiac physical examination skills using simulation technology and real patients: a comparison study.

PubMed

Hatala, Rose; Issenberg, S Barry; Kassen, Barry; Cole, Gary; Bacchus, C Maria; Scalese, Ross J

2008-06-01

High-stakes assessments of doctors' physical examination skills often employ standardised patients (SPs) who lack physical abnormalities. Simulation technology provides additional opportunities to assess these skills by mimicking physical abnormalities. The current study examined the relationship between internists' cardiac physical examination competence as assessed with simulation technology compared with that assessed with real patients (RPs). The cardiac physical examination skills and bedside diagnostic accuracy of 28 internists were assessed during an objective structured clinical examination (OSCE). The OSCE included 3 modalities of cardiac patients: RPs with cardiac abnormalities; SPs combined with computer-based, audio-video simulations of auscultatory abnormalities, and a cardiac patient simulator (CPS) manikin. Four cardiac diagnoses and their associated cardiac findings were matched across modalities. At each station, 2 examiners independently rated a participant's physical examination technique and global clinical competence. Two investigators separately scored diagnostic accuracy. Inter-rater reliability between examiners for global ratings (GRs) ranged from 0.75-0.78 for the different modalities. Although there was no significant difference between participants' mean GRs for each modality, the correlations between participants' performances on each modality were low to modest: RP versus SP, r = 0.19; RP versus CPS, r = 0.22; SP versus CPS, r = 0.57 (P < 0.01). Methodological limitations included variability between modalities in the components contributing to examiners' GRs, a paucity of objective outcome measures and restricted case sampling. No modality provided a clear 'gold standard' for the assessment of cardiac physical examination competence. These limitations need to be addressed before determining the optimal patient modality for high-stakes assessment purposes.

ARCHERRT – A GPU-based and photon-electron coupled Monte Carlo dose computing engine for radiation therapy: Software development and application to helical tomotherapy

PubMed Central

Su, Lin; Yang, Youming; Bednarz, Bryan; Sterpin, Edmond; Du, Xining; Liu, Tianyu; Ji, Wei; Xu, X. George

2014-01-01

Purpose: Using the graphical processing units (GPU) hardware technology, an extremely fast Monte Carlo (MC) code ARCHERRT is developed for radiation dose calculations in radiation therapy. This paper describes the detailed software development and testing for three clinical TomoTherapy® cases: the prostate, lung, and head & neck. Methods: To obtain clinically relevant dose distributions, phase space files (PSFs) created from optimized radiation therapy treatment plan fluence maps were used as the input to ARCHERRT. Patient-specific phantoms were constructed from patient CT images. Batch simulations were employed to facilitate the time-consuming task of loading large PSFs, and to improve the estimation of statistical uncertainty. Furthermore, two different Woodcock tracking algorithms were implemented and their relative performance was compared. The dose curves of an Elekta accelerator PSF incident on a homogeneous water phantom were benchmarked against DOSXYZnrc. For each of the treatment cases, dose volume histograms and isodose maps were produced from ARCHERRT and the general-purpose code, GEANT4. The gamma index analysis was performed to evaluate the similarity of voxel doses obtained from these two codes. The hardware accelerators used in this study are one NVIDIA K20 GPU, one NVIDIA K40 GPU, and six NVIDIA M2090 GPUs. In addition, to make a fairer comparison of the CPU and GPU performance, a multithreaded CPU code was developed using OpenMP and tested on an Intel E5-2620 CPU. Results: For the water phantom, the depth dose curve and dose profiles from ARCHERRT agree well with DOSXYZnrc. For clinical cases, results from ARCHERRT are compared with those from GEANT4 and good agreement is observed. Gamma index test is performed for voxels whose dose is greater than 10% of maximum dose. For 2%/2mm criteria, the passing rates for the prostate, lung case, and head & neck cases are 99.7%, 98.5%, and 97.2%, respectively. Due to specific architecture of GPU, modified Woodcock tracking algorithm performed inferior to the original one. ARCHERRT achieves a fast speed for PSF-based dose calculations. With a single M2090 card, the simulations cost about 60, 50, 80 s for three cases, respectively, with the 1% statistical error in the PTV. Using the latest K40 card, the simulations are 1.7–1.8 times faster. More impressively, six M2090 cards could finish the simulations in 8.9–13.4 s. For comparison, the same simulations on Intel E5-2620 (12 hyperthreading) cost about 500–800 s. Conclusions: ARCHERRT was developed successfully to perform fast and accurate MC dose calculation for radiotherapy using PSFs and patient CT phantoms. PMID:24989378

ARCHERRT - a GPU-based and photon-electron coupled Monte Carlo dose computing engine for radiation therapy: software development and application to helical tomotherapy.

PubMed

Su, Lin; Yang, Youming; Bednarz, Bryan; Sterpin, Edmond; Du, Xining; Liu, Tianyu; Ji, Wei; Xu, X George

2014-07-01

Using the graphical processing units (GPU) hardware technology, an extremely fast Monte Carlo (MC) code ARCHERRT is developed for radiation dose calculations in radiation therapy. This paper describes the detailed software development and testing for three clinical TomoTherapy® cases: the prostate, lung, and head & neck. To obtain clinically relevant dose distributions, phase space files (PSFs) created from optimized radiation therapy treatment plan fluence maps were used as the input to ARCHERRT. Patient-specific phantoms were constructed from patient CT images. Batch simulations were employed to facilitate the time-consuming task of loading large PSFs, and to improve the estimation of statistical uncertainty. Furthermore, two different Woodcock tracking algorithms were implemented and their relative performance was compared. The dose curves of an Elekta accelerator PSF incident on a homogeneous water phantom were benchmarked against DOSXYZnrc. For each of the treatment cases, dose volume histograms and isodose maps were produced from ARCHERRT and the general-purpose code, GEANT4. The gamma index analysis was performed to evaluate the similarity of voxel doses obtained from these two codes. The hardware accelerators used in this study are one NVIDIA K20 GPU, one NVIDIA K40 GPU, and six NVIDIA M2090 GPUs. In addition, to make a fairer comparison of the CPU and GPU performance, a multithreaded CPU code was developed using OpenMP and tested on an Intel E5-2620 CPU. For the water phantom, the depth dose curve and dose profiles from ARCHERRT agree well with DOSXYZnrc. For clinical cases, results from ARCHERRT are compared with those from GEANT4 and good agreement is observed. Gamma index test is performed for voxels whose dose is greater than 10% of maximum dose. For 2%/2mm criteria, the passing rates for the prostate, lung case, and head & neck cases are 99.7%, 98.5%, and 97.2%, respectively. Due to specific architecture of GPU, modified Woodcock tracking algorithm performed inferior to the original one. ARCHERRT achieves a fast speed for PSF-based dose calculations. With a single M2090 card, the simulations cost about 60, 50, 80 s for three cases, respectively, with the 1% statistical error in the PTV. Using the latest K40 card, the simulations are 1.7-1.8 times faster. More impressively, six M2090 cards could finish the simulations in 8.9-13.4 s. For comparison, the same simulations on Intel E5-2620 (12 hyperthreading) cost about 500-800 s. ARCHERRT was developed successfully to perform fast and accurate MC dose calculation for radiotherapy using PSFs and patient CT phantoms.

Usefulness of three-dimensional(3D) simulation software in hepatectomy for pediatric hepatoblastoma.

PubMed

Zhang, Gang; Zhou, Xian-Jun; Zhu, Cheng-Zhan; Dong, Qian; Su, Lin

2016-09-01

Hepatoblastoma (HB) is the most common malignant liver tumor in childhood. Complete HB surgical resection which is technically demanding is the cornerstone of effective therapy with a good prognosis. The aim of our study is to evaluate the usefulness of 3D simulation software in assisting hepatectomy in pediatric patients with HB. 21 children with HB who underwent hepatectomy were enrolled in this study. All patients underwent computer tomography (CT) imaging preoperatively. CT images from 11 cases (from September 2013 to August 2015) were reconstructed with Hisense CAS, and performed hetpatectomy. While 10 cases (from September 2011 to August 2013) without 3D simulation were token as the control group. The clinical outcome were analyzed and compared between the 2 groups. All the HB were successfully removed for all patients and there was no positive margins in the surgical specimens, no complications, and no recurrences. For the reconstructing group, 3D simulation software successfully reconstructed the 3D images of liver and were used as a navigator in the operation room during hepatectomy. Anatomic hepatectomy were successfully completed for all patients after operation planning using the software. There was no obvious discrepancy between the virtual and the actual hepatectomy. The mean operation time was shorter (142.18 ± 21.87 min VS. the control group, 173.5 ± 54.88 min, p = 0.047) and intraoperative bleeding was less (28.73 ± 14.17 ml VS. 42.8 ± 41.12 ml, p = 0.011) in the reconstructing group. Moreover, postoperative hospital stay tended to be shorter in the reconstructing group (11.18 ± 2.78d VS. the control group 13 ± 3.46d, P = 0.257). 3D simulation software facilitates the investigation of the complex liver structure, contributes to the optimal operation planning, and enables an individualized anatomic hepatectomy for each pediatric patient with HB. Copyright © 2016 Elsevier Ltd. All rights reserved.

SU-F-J-43: Positional Variation of Implanted Fiducial Markers Over the Course of Image Guided Radiotherapy for Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, S; Jacob, R; Popple, R

2016-06-15

Purpose: Pancreas is a soft-tissue organ, implanted fiducials can change positions due to migration or tissue deformation. This study quantified positional variation of fiducials in IGRT for pancreatic cancer. Methods: 20 patients had at least 3 gold fiducials implanted in pancreas under EUS guidance. Patients had 4D-CT simulation for gated treatment. Daily gated OBI kV images (Turebeam) were used for positional alignment with fiducials for total of 25 or 28 fractions. Relative distances among 3 fiducials (d{sub 1–} {sub 2}, d{sub 1–3}, d{sub 2–3}) were measured from 4D-CT end-of-expiration phase bin; and from gated kV images in first, mid, andmore » last fraction (n=180). Results: The median duration between implant and simulation was 11 (range 0–41) days. The median duration between simulation and first fraction was 17 (range 8–24) days. The median relative distance was 12 (range 4–78) mm for d{sub 1–2}, 24 (range 6–80) mm for d{sub 1–3}, and 19 (range 5–63) mm for d{sub 2–3}. The median deviation was 1 mm for d{sub 1–2}, d{sub 1–3}, d{sub 2–3} between simulation and first fraction, first and mid fraction, mid and last fraction (n=180). Two patients (10%) had deviation >= 5 mm (5, 11 mm) between simulation and first fraction. One patient (5%) had deviation >= 5 mm (11 mm) between first and mid fraction. No patient (0%) had deviation >= 5 mm between mid and last fraction. In all 3 cases with deviation >=5 mm, only one fiducial was significantly deviated. No clear evidence that deviation size was associated with time interval between implant and first fraction. Conclusion: Implanted gold fiducials were quite stable over time in their relative positions in pancreas. Our data suggested at least 3 fiducials are needed. In cases that one fiducial was significantly deviated in daily kV images, this fiducial should be excluded in image guidance.« less

Modeling of Radiotherapy Linac Source Terms Using ARCHER Monte Carlo Code: Performance Comparison for GPU and MIC Parallel Computing Devices

NASA Astrophysics Data System (ADS)

Lin, Hui; Liu, Tianyu; Su, Lin; Bednarz, Bryan; Caracappa, Peter; Xu, X. George

2017-09-01

Monte Carlo (MC) simulation is well recognized as the most accurate method for radiation dose calculations. For radiotherapy applications, accurate modelling of the source term, i.e. the clinical linear accelerator is critical to the simulation. The purpose of this paper is to perform source modelling and examine the accuracy and performance of the models on Intel Many Integrated Core coprocessors (aka Xeon Phi) and Nvidia GPU using ARCHER and explore the potential optimization methods. Phase Space-based source modelling for has been implemented. Good agreements were found in a tomotherapy prostate patient case and a TrueBeam breast case. From the aspect of performance, the whole simulation for prostate plan and breast plan cost about 173s and 73s with 1% statistical error.

Cost-minimization analysis favours intravenous ferric carboxymaltose over ferric sucrose or oral iron as preoperative treatment in patients with colon cancer and iron deficiency anaemia.

PubMed

Calvet, Xavier; Gené, Emili; ÀngelRuíz, Miquel; Figuerola, Ariadna; Villoria, Albert; Cucala, Mercedes; Mearin, Fermín; Delgado, Salvadora; Calleja, Jose Luis

2016-01-01

Ferric Carboxymaltose (FCM), Iron Sucrose (IS) and Oral Iron (OI) are alternative treatments for preoperative anaemia. To compare the cost implications, using a cost-minimization analysis, of three alternatives: FCM vs. IS vs. OI for treating iron-deficient anaemia before surgery in patients with colon cancer. Data from 282 patients with colorectal cancer and anaemia were obtained from a previous study. One hundred and eleven received FCS, 16 IS and 155 OI. Costs of intravenous iron drugs were obtained from the Spanish Regulatory Agency. Direct and indirect costs were obtained from the analytical accounting unit of the Hospital. In the base case mean costs per patient were calculated. Sensitivity analysis and probabilistic Monte Carlo simulation were performed. Total costs per patient were 1827® in the FCM group, 2312® in the IS group and 2101® in the OI group. Cost savings per patient for FCM treatment were 485® compared to IS and 274® compared to OI. A Monte Carlo simulation favoured the use of FCM in 84.7% and 84.4% of simulations when compared to IS and OI, respectively. FCM infusion before surgery reduced costs in patients with colon cancer and iron-deficiency anaemia when compared with OI and IS.

Aortic dissection simulation models for clinical support: fluid-structure interaction vs. rigid wall models.

PubMed

Alimohammadi, Mona; Sherwood, Joseph M; Karimpour, Morad; Agu, Obiekezie; Balabani, Stavroula; Díaz-Zuccarini, Vanessa

2015-04-15

The management and prognosis of aortic dissection (AD) is often challenging and the use of personalised computational models is being explored as a tool to improve clinical outcome. Including vessel wall motion in such simulations can provide more realistic and potentially accurate results, but requires significant additional computational resources, as well as expertise. With clinical translation as the final aim, trade-offs between complexity, speed and accuracy are inevitable. The present study explores whether modelling wall motion is worth the additional expense in the case of AD, by carrying out fluid-structure interaction (FSI) simulations based on a sample patient case. Patient-specific anatomical details were extracted from computed tomography images to provide the fluid domain, from which the vessel wall was extrapolated. Two-way fluid-structure interaction simulations were performed, with coupled Windkessel boundary conditions and hyperelastic wall properties. The blood was modelled using the Carreau-Yasuda viscosity model and turbulence was accounted for via a shear stress transport model. A simulation without wall motion (rigid wall) was carried out for comparison purposes. The displacement of the vessel wall was comparable to reports from imaging studies in terms of intimal flap motion and contraction of the true lumen. Analysis of the haemodynamics around the proximal and distal false lumen in the FSI model showed complex flow structures caused by the expansion and contraction of the vessel wall. These flow patterns led to significantly different predictions of wall shear stress, particularly its oscillatory component, which were not captured by the rigid wall model. Through comparison with imaging data, the results of the present study indicate that the fluid-structure interaction methodology employed herein is appropriate for simulations of aortic dissection. Regions of high wall shear stress were not significantly altered by the wall motion, however, certain collocated regions of low and oscillatory wall shear stress which may be critical for disease progression were only identified in the FSI simulation. We conclude that, if patient-tailored simulations of aortic dissection are to be used as an interventional planning tool, then the additional complexity, expertise and computational expense required to model wall motion is indeed justified.

LBM-EP: Lattice-Boltzmann method for fast cardiac electrophysiology simulation from 3D images.

PubMed

Rapaka, S; Mansi, T; Georgescu, B; Pop, M; Wright, G A; Kamen, A; Comaniciu, Dorin

2012-01-01

Current treatments of heart rhythm troubles require careful planning and guidance for optimal outcomes. Computational models of cardiac electrophysiology are being proposed for therapy planning but current approaches are either too simplified or too computationally intensive for patient-specific simulations in clinical practice. This paper presents a novel approach, LBM-EP, to solve any type of mono-domain cardiac electrophysiology models at near real-time that is especially tailored for patient-specific simulations. The domain is discretized on a Cartesian grid with a level-set representation of patient's heart geometry, previously estimated from images automatically. The cell model is calculated node-wise, while the transmembrane potential is diffused using Lattice-Boltzmann method within the domain defined by the level-set. Experiments on synthetic cases, on a data set from CESC'10 and on one patient with myocardium scar showed that LBM-EP provides results comparable to an FEM implementation, while being 10 - 45 times faster. Fast, accurate, scalable and requiring no specific meshing, LBM-EP paves the way to efficient and detailed models of cardiac electrophysiology for therapy planning.

Solving the patient zero inverse problem by using generalized simulated annealing

NASA Astrophysics Data System (ADS)

Menin, Olavo H.; Bauch, Chris T.

2018-01-01

Identifying patient zero - the initially infected source of a given outbreak - is an important step in epidemiological investigations of both existing and emerging infectious diseases. Here, the use of the Generalized Simulated Annealing algorithm (GSA) to solve the inverse problem of finding the source of an outbreak is studied. The classical disease natural histories susceptible-infected (SI), susceptible-infected-susceptible (SIS), susceptible-infected-recovered (SIR) and susceptible-infected-recovered-susceptible (SIRS) in a regular lattice are addressed. Both the position of patient zero and its time of infection are considered unknown. The algorithm performance with respect to the generalization parameter q˜v and the fraction ρ of infected nodes for whom infection was ascertained is assessed. Numerical experiments show the algorithm is able to retrieve the epidemic source with good accuracy, even when ρ is small, but present no evidence to support that GSA performs better than its classical version. Our results suggest that simulated annealing could be a helpful tool for identifying patient zero in an outbreak where not all cases can be ascertained.

Nephrogenic adenoma of the urinary tract: A 6-year single center experience.

PubMed

Turcan, Didem; Acikalin, Mustafa Fuat; Yilmaz, Evrim; Canaz, Funda; Arik, Deniz

2017-07-01

Nephrogenic adenoma is an uncommon benign lesion that occurs at several sites in urinary tract, from the renal pelvis to urethra, with the highest frequency in urinary bladder. Nephrogenic adenoma displays a broad spectrum of architectural and cytological features. Hence, recognition of its characteristic histopathological features is needed to distinguish this lesion from its mimickers. A retrospective series of 21 cases of nephrogenic adenoma in 18 patients, which were diagnosed in our department between 2010 and 2016, were analyzed. All histological slides were reviewed by two pathologists and the diagnosis of each case was confirmed. Immunohistochemistry was performed for PAX-8 in all cases. CK7, PAX-2, PSA, p53, p63, GATA-3 and α-methylacyl-CoA racemase (AMACR) were applied in problematic cases. The most common location of the lesion was urinary bladder (14 patients) followed by renal pelvis (2 patients), ureter (1 patient) and urethra (1 patient). A history of urothelial carcinoma and repeated TUR procedures were observed in 12 patients. There were 2 pediatric patients aged 3 years. Both of them had undergone previous urosurgery because of megaureter in one and bladder exstrophy in the other. Other clinical antecedents included bladder diverticulum (1 patient), cystitis (1 patient) and nephrolithiasis (1 patient). Recurrence of lesion was seen in two patients (once in one case and twice in the other one). The median time to disease recurrence in these patients was 11 months (range, 2-20 months). Histologically, the lesions exhibited various morphological findings, with mixed (15 cases, 71.4%), pure tubular (3 cases, 14.3%), pure papillary (2 cases, 9.5%) and pure flat (1 case, 4.8%) growth patterns. Of the 15 cases with mixed patterns, 8 cases were tubulocystic and flat, 3 cases were tubular and flat, 2 cases were tubular, papillary and flat, 1 case was tubulocystic, papillary and flat, and 1 case was tubular and papillary. Flat pattern was observed in 15 cases (71.4%). It was seen in association with other patterns in 14 cases (mixed morphology) and purely in 1 case. Our findings suggested that the flat pattern is a frequent finding in nephrogenic adenomas. Notably one case in this series showed superficial extension into bladder muscularis propria. Histologically nephrogenic adenoma may simulate a variety of malignancies. Awareness of characteristic morphologic features of nephrogenic adenoma is needed to diagnose this lesion correctly. Copyright © 2017 Elsevier GmbH. All rights reserved.

Design and development of compact monitoring system for disaster remote health centres.

PubMed

Santhi, S; Sadasivam, G S

2015-02-01

To enhance speedy communication between the patient and the doctor through newly proposed routing protocol at the mobile node. The proposed model is applied for a telemedicine application during disaster recovery management. In this paper, Energy Efficient Link Stability Routing Protocol (EELSRP) has been developed by simulation and real time. This framework is designed for the immediate healing of affected persons in remote areas, especially at the time of the disaster where there is no hospital proximity. In case of disasters, there might be an outbreak of infectious diseases. In such cases, the patient's medical record is also transferred by the field operator from disaster place to the hospital to facilitate the identification of the disease-causing agent and to prescribe the necessary medication. The heterogeneous networking framework provides reliable, energy efficientand speedy communication between the patient and the doctor using the proposed routing protocol at the mobile node. The performance of the simulation and real time versions of the Energy Efficient Link Stability Routing Protocol (EELSRP) protocol has been analyzed. Experimental results prove the efficiency of the real-time version of EESLRP protocol. The packet delivery ratio and throughput of the real time version of EELSRP protocol is increased by 3% and 10%, respectively, when compared to the simulated version of EELSRP. The end-to-end delay and energy consumption are reduced by 10% and 2% in the real time version of EELSRP.

What are the appropriate methods for analyzing patient-reported outcomes in randomized trials when data are missing?

PubMed

Hamel, J F; Sebille, V; Le Neel, T; Kubis, G; Boyer, F C; Hardouin, J B

2017-12-01

Subjective health measurements using Patient Reported Outcomes (PRO) are increasingly used in randomized trials, particularly for patient groups comparisons. Two main types of analytical strategies can be used for such data: Classical Test Theory (CTT) and Item Response Theory models (IRT). These two strategies display very similar characteristics when data are complete, but in the common case when data are missing, whether IRT or CTT would be the most appropriate remains unknown and was investigated using simulations. We simulated PRO data such as quality of life data. Missing responses to items were simulated as being completely random, depending on an observable covariate or on an unobserved latent trait. The considered CTT-based methods allowed comparing scores using complete-case analysis, personal mean imputations or multiple-imputations based on a two-way procedure. The IRT-based method was the Wald test on a Rasch model including a group covariate. The IRT-based method and the multiple-imputations-based method for CTT displayed the highest observed power and were the only unbiased method whatever the kind of missing data. Online software and Stata® modules compatibles with the innate mi impute suite are provided for performing such analyses. Traditional procedures (listwise deletion and personal mean imputations) should be avoided, due to inevitable problems of biases and lack of power.

Simulated human patients and patient-centredness: The uncanny hybridity of nursing education, technology, and learning to care.

PubMed

Ireland, Aileen V

2017-01-01

Positioned within a hybrid of the human and technology, professional nursing practice has always occupied a space that is more than human. In nursing education, technology is central in providing tools with which practice knowledge is mobilized so that students can safely engage with simulated human patients without causing harm to real people. However, while there is an increased emphasis on deploying these simulated humans as emissaries from person-centred care to demonstrate what it is like to care for real humans, the nature of what is really going on in simulation-what is real and what is simulated-is very rarely discussed and poorly understood. This paper explores how elements of postcolonial critical thought can aid in understanding the challenges of educating nurses to provide person-centred care within a healthcare culture that is increasingly reliant on technology. Because nursing education is itself a hybrid of real and simulated practice, it provides an appropriate case study to explore the philosophical question of technology in healthcare discourse, particularly as it relates to the relationship between the human patient and its uncanny simulated double. Drawing on postcolonial elements such as the uncanny, diaspora, hybridity, and créolité, the hybrid conditions of nursing education are examined in order to open up new possibilities of thinking about how learning to care is entangled with this technological space to assist in shaping professional knowledge of person-centred care. Considering these issues through a postcolonial lens opens up questions about the nature of the difficulty in using simulated human technologies in clinical education, particularly with the paradoxical aim of providing person-centred care within a climate that increasingly characterized as posthuman. © 2016 John Wiley & Sons Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toltz, A; Seuntjens, J; Hoesl, M

Purpose: With the aim of reducing acute esophageal radiation toxicity in pediatric patients receiving craniospinal irradiation (CSI), we investigated the implementation of an in-vivo, adaptive proton therapy range verification methodology. Simulation experiments and in-phantom measurements were conducted to validate the range verification technique for this clinical application. Methods: A silicon diode array system has been developed and experimentally tested in phantom for passively scattered proton beam range verification for a prostate treatment case by correlating properties of the detector signal to the water equivalent path length (WEPL). We propose to extend the methodology to verify range distal to the vertebralmore » body for pediatric CSI cases by placing this small volume dosimeter in the esophagus of the anesthetized patient immediately prior to treatment. A set of calibration measurements was performed to establish a time signal to WEPL fit for a “scout” beam in a solid water phantom. Measurements are compared against Monte Carlo simulation in GEANT4 using the Tool for Particle Simulation (TOPAS). Results: Measurements with the diode array in a spread out Bragg peak of 14 cm modulation width and 15 cm range (177 MeV passively scattered beam) in solid water were successfully validated against proton fluence rate simulations in TOPAS. The resulting calibration curve allows for a sensitivity analysis of detector system response with dose rate in simulation and with individual diode position through simulation on patient CT data. Conclusion: Feasibility has been shown for the application of this range verification methodology to pediatric CSI. An in-vivo measurement to determine the WEPL to the inner surface of the esophagus will allow for personalized adjustment of the treatment plan to ensure sparing of the esophagus while confirming target coverage. A Toltz acknowledges partial support by the CREATE Medical Physics Research Training Network grant of the Natural Sciences and Engineering Research Council (Grant number: 432290)« less

Night driving simulation in a randomized prospective comparison of Visian toric implantable collamer lens and conventional PRK for moderate to high myopic astigmatism.

PubMed

Schallhorn, Steven; Tanzer, David; Sanders, Donald R; Sanders, Monica; Brown, Mitch; Kaupp, Sandor E

2010-05-01

To compare changes in simulated night driving performance after Visian Toric Implantable Collamer Lens (TICL; STAAR Surgical) implantation and photorefractive keratectomy (PRK) for the correction of moderate to high myopic astigmatism. This prospective, randomized study consisted of 43 eyes implanted with the TICL (20 bilateral cases) and 45 eyes receiving conventional PRK (VISX Star S3 excimer laser) with mitomycin C (22 bilateral cases) for moderate to high myopia (-6.00 to -20.00 diopters[D] sphere) measured at the spectacle plane and 1.00 to 4.00 D of astigmatism. As a substudy, 27 eyes of 14 TICL patients and 41 eyes of 21 PRK patients underwent a simulated night driving test. The detection and identification distances of road signs and hazards with the Night Driving Simulator (Vision Sciences Research Corp) were measured with and without a glare source before and 6 months after each procedure. No significant difference was noted in the pre- to postoperative Night Driving Simulator in detection distances with and without the glare source between the TICL and PRK groups. The differences in identification distances without glare were significantly better for business and traffic road signs and pedestrian hazards in the TICL group relative to the PRK group whereas with glare, only the pedestrian hazards were significantly better. A clinically relevant change of Night Driving Simulator performance (>0.5 seconds change in ability to identify tasks postoperatively) was significantly better in the TICL group (with and without glare) for all identification tasks. The TICL performed better than conventional PRK in the pre- to postoperative Night Driving Simulator testing with and without a glare source present. Copyright 2010, SLACK Incorporated.

Implementation of Monte Carlo Dose calculation for CyberKnife treatment planning

NASA Astrophysics Data System (ADS)

Ma, C.-M.; Li, J. S.; Deng, J.; Fan, J.

2008-02-01

Accurate dose calculation is essential to advanced stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) especially for treatment planning involving heterogeneous patient anatomy. This paper describes the implementation of a fast Monte Carlo dose calculation algorithm in SRS/SRT treatment planning for the CyberKnife® SRS/SRT system. A superposition Monte Carlo algorithm is developed for this application. Photon mean free paths and interaction types for different materials and energies as well as the tracks of secondary electrons are pre-simulated using the MCSIM system. Photon interaction forcing and splitting are applied to the source photons in the patient calculation and the pre-simulated electron tracks are repeated with proper corrections based on the tissue density and electron stopping powers. Electron energy is deposited along the tracks and accumulated in the simulation geometry. Scattered and bremsstrahlung photons are transported, after applying the Russian roulette technique, in the same way as the primary photons. Dose calculations are compared with full Monte Carlo simulations performed using EGS4/MCSIM and the CyberKnife treatment planning system (TPS) for lung, head & neck and liver treatments. Comparisons with full Monte Carlo simulations show excellent agreement (within 0.5%). More than 10% differences in the target dose are found between Monte Carlo simulations and the CyberKnife TPS for SRS/SRT lung treatment while negligible differences are shown in head and neck and liver for the cases investigated. The calculation time using our superposition Monte Carlo algorithm is reduced up to 62 times (46 times on average for 10 typical clinical cases) compared to full Monte Carlo simulations. SRS/SRT dose distributions calculated by simple dose algorithms may be significantly overestimated for small lung target volumes, which can be improved by accurate Monte Carlo dose calculations.

Pilot study on effectiveness of simulation for surgical robot design using manipulability.

PubMed

Kawamura, Kazuya; Seno, Hiroto; Kobayashi, Yo; Fujie, Masakatsu G

2011-01-01

Medical technology has advanced with the introduction of robot technology, which facilitates some traditional medical treatments that previously were very difficult. However, at present, surgical robots are used in limited medical domains because these robots are designed using only data obtained from adult patients and are not suitable for targets having different properties, such as children. Therefore, surgical robots are required to perform specific functions for each clinical case. In addition, the robots must exhibit sufficiently high movability and operability for each case. In the present study, we focused on evaluation of the mechanism and configuration of a surgical robot by a simulation based on movability and operability during an operation. We previously proposed the development of a simulator system that reproduces the conditions of a robot and a target in a virtual patient body to evaluate the operability of the surgeon during an operation. In the present paper, we describe a simple experiment to verify the condition of the surgical assisting robot during an operation. In this experiment, the operation imitating suturing motion was carried out in a virtual workspace, and the surgical robot was evaluated based on manipulability as an indicator of movability. As the result, it was confirmed that the robot was controlled with low manipulability of the left side manipulator during the suturing. This simulation system can verify the less movable condition of a robot before developing an actual robot. Our results show the effectiveness of this proposed simulation system.

An 'inflammatory' variant of solar purpura: a simulant of leukocytoclastic vasculitis and neutrophilic dermatoses.

PubMed

Wood, Benjamin A; LeBoit, Philip E

2013-08-01

To study the clinical and pathological features of cases of apparent solar purpura, with attention to the recently described phenomenon of inflammatory changes within otherwise typical lesions. We studied 95 cases diagnosed as solar purpura and identified 10 cases (10.5%) in which significant neutrophilic inflammation was present, potentially simulating a leukocytoclastic vasculitis or neutrophilic dermatosis. An additional three cases were identified in subsequent routine practice. The clinical features, including follow-up for subsequent development of vasculitis and histological features were studied. In all cases the histological features were typical of solar purpura, with the exception of inflammatory changes, typically associated with clefting of elastotic stroma. Clinical follow-up information was available for all patients and none developed subsequent evidence of a cutaneous or systemic vasculitis or neutrophilic dermatosis. Inflammatory changes appear to be more frequent in solar purpura than is generally recognised. Awareness of this histological variation and correlation with the clinical findings and evolution is important in avoiding misdiagnosis.

Anaplastic ependymoma simulating glioblastoma in the cerebrum of an adult.

PubMed

Shintaku, Masayuki; Hashimoto, Kenji

2012-01-01

A case of anaplastic ependymoma of the cerebral hemisphere in which the histopathological features closely simulated those of glioblastoma is reported. The patient was a 72-year-old woman with a large, well-demarcated tumor in the left temporal lobe. The tumor was totally extirpated, but recurred 18 months later, and the patient died after 4 months. The extirpated tumor was well circumscribed from the surrounding brain tissue and consisted of a sheet-like, dense proliferation of atypical, short spindle or polygonal cells. Extensive geographic necrosis with nuclear pseudopalisading was seen. Although perivascular pseudorosettes were observed in many areas, true ependymal rosettes were absent. Immunohistochemistry for glial fibrillary acidic protein and epithelial membrane antigen and ultrastructural study confirmed the ependymal nature of tumor cells. The histopathological spectrum of anaplastic ependymoma is very wide and reflects the basically dual characteristics of ependymal cells: epithelial and glial phenotypes. The present case indicates that some anaplastic ependymomas strongly express the glial phenotype and also show remarkable anaplastic cytological features, thus closely simulating glioblastoma. The diagnostic criteria for anaplastic ependymoma, and the nosological position of highly anaplastic ependymoma and its possible clinical implications, are briefly discussed.

Differences in Faculty and Standardized Patient Scores on Professionalism for Second-Year Podiatric Medical Students During a Standardized Simulated Patient Encounter.

PubMed

Mahoney, James M; Vardaxis, Vassilios; Anwar, Noreen; Hagenbucher, Jacob

2018-03-01

This study examined the differences between faculty and trained standardized patient (SP) evaluations on student professionalism during a second-year podiatric medicine standardized simulated patient encounter. Forty-nine second-year podiatric medicine students were evaluated for their professionalism behavior. Eleven SPs performed an assessment in real-time, and one faculty member performed a secondary assessment after observing a videotape of the encounter. Five domains were chosen for evaluation from a validated professionalism assessment tool. Significant differences were identified in the professionalism domains of "build a relationship" ( P = .008), "gather information" ( P = .001), and share information ( P = .002), where the faculty scored the students higher than the SP for 24.5%, 18.9%, and 26.5% of the cases, respectively. In addition, the faculty scores were higher than the SP scores in all of the "gather information" subdomains; however, the difference in scores was significant only in the "question appropriately" ( P = .001) and "listen and clarify" ( P = .003) subdomains. This study showed that professionalism scores for second-year podiatric medical students during a simulated patient encounter varied significantly between faculty and SPs. Further consideration needs to be given to determine the source of these differences.

Roles and Educational Effects of Clinical Case Studies in Home Medical Care.

PubMed

Ohsawa, Tomoji; Shimazoe, Takao

2017-01-01

Due to the progression of aging in Japan, pharmacists need to participate in home medical care. To enable pharmacists with no previous experience to participate in home medical care of patients with various diseases in the home environment, it is necessary to adopt an approach of training them in advance. It is thought useful for such clinical training to include patient case studies, which may facilitate the training of pharmacists for home medical care through simulated experience. "The working group to create home clinical cases for education" was launched by a group of university faculty, who have educational knowledge, and trained pharmacists who work with the patients at home. The home care cases were compiled by the university faculty members and the home care practice pharmacists. Working pharmacists and students at pharmaceutical college studied the same case studies of home medical care, and their self-evaluations were compared. They showed that the students rated themselves higher than the pharmacists. One of the reasons was the systematic education of the case studies. The clinical case studies are a good educational tool to promote home care medicine in pharmacies and university pharmaceutical colleges.

Improving nurses' perceptions of competency in diabetes self-management education through the use of simulation and problem-based learning.

PubMed

Tschannen, Dana; Aebersold, Michelle; Sauter, Cecilia; Funnell, Martha M

2013-06-01

Nurses who provide case management can improve care practice and outcomes among patients who have type 2 diabetes through appropriate training and systems of care. This study was conducted to improve ambulatory care nurses' perceptions of competency in empowerment-based skills required for diabetes self-management education after participation in a multifaceted educational session that included problem-based learning and simulation. After participation in the multifaceted educational session, nurses (n = 21) perceived that the education provided an excellent opportunity for knowledge uptake and applicability to their respective work settings. The learning strategies provided opportunities for engagement in a safe and relaxed atmosphere. The simulation experience allowed participants to deliberately practice the competencies. These nurses considered this a very effective learning activity. Through the use of problem-based learning and simulation, nurses may be able to more efficiently and effectively develop the necessary skills to provide effective case management of chronic disease. Copyright 2013, SLACK Incorporated.

Cost-effectiveness of diabetes case management for low-income populations.

PubMed

Gilmer, Todd P; Roze, Stéphane; Valentine, William J; Emy-Albrecht, Katrina; Ray, Joshua A; Cobden, David; Nicklasson, Lars; Philis-Tsimikas, Athena; Palmer, Andrew J

2007-10-01

To evaluate the cost-effectiveness of Project Dulce, a culturally specific diabetes case management and self-management training program, in four cohorts defined by insurance status. Clinical and cost data on 3,893 persons with diabetes participating in Project Dulce were used as inputs into a diabetes simulation model. The Center for Outcomes Research Diabetes Model, a published, peer-reviewed and validated simulation model of diabetes, was used to evaluate life expectancy, quality-adjusted life expectancy (QALY), cumulative incidence of complications and direct medical costs over patient lifetimes (40-year time horizon) from a third-party payer perspective. Cohort characteristics, treatment effects, and case management costs were derived using a difference in difference design comparing data from the Project Dulce program to a cohort of historical controls. Long-term costs were derived from published U.S. sources. Costs and clinical benefits were discounted at 3.0 percent per annum. Sensitivity analyses were performed. Incremental cost-effectiveness ratios of $10,141, $24,584, $44,941, and $69,587 per QALY gained were estimated for Project Dulce participants versus control in the uninsured, County Medical Services, Medi-Cal, and commercial insurance cohorts, respectively. The Project Dulce diabetes case management program was associated with cost-effective improvements in quality-adjusted life expectancy and decreased incidence of diabetes-related complications over patient lifetimes. Diabetes case management may be particularly cost effective for low-income populations.

Renal surgery in the new millennium.

PubMed

Delvecchio, F C; Preminger, G M

2000-11-01

In the not too distant future, the minimally invasive renal surgeon will be able to practice an operation on a difficult case on a three-dimensional virtual reality simulator, providing all attributes of the real procedure. The patient's imaging studies will be imported into the simulator to better mimic particular anatomy. When confident enough of his or her skills, the surgeon will start operating on the patient using the same virtual reality simulator/telepresence surgery console system, which will permit the live surgery to be conducted by robots hundreds of miles away. The robots will manipulate miniature endoscopes or control minimally or noninvasive ablative technologies. Endoscopic/laparoscopic footage of the surgical procedure will be stored digitally in optical disks to be used later in telementoring of a surgery resident. All this and more will be possible in the not so distant third millennium.

[Simulation of lung motions using an artificial neural network].

PubMed

Laurent, R; Henriet, J; Salomon, M; Sauget, M; Nguyen, F; Gschwind, R; Makovicka, L

2011-04-01

A way to improve the accuracy of lung radiotherapy for a patient is to get a better understanding of its lung motion. Indeed, thanks to this knowledge it becomes possible to follow the displacements of the clinical target volume (CTV) induced by the lung breathing. This paper presents a feasibility study of an original method to simulate the positions of points in patient's lung at all breathing phases. This method, based on an artificial neural network, allowed learning the lung motion on real cases and then to simulate it for new patients for which only the beginning and the end breathing data are known. The neural network learning set is made up of more than 600 points. These points, shared out on three patients and gathered on a specific lung area, were plotted by a MD. The first results are promising: an average accuracy of 1mm is obtained for a spatial resolution of 1 × 1 × 2.5mm(3). We have demonstrated that it is possible to simulate lung motion with accuracy using an artificial neural network. As future work we plan to improve the accuracy of our method with the addition of new patient data and a coverage of the whole lungs. Copyright © 2010 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

Lenticular fibroxanthomatous nodule.

PubMed

Lee, Seok J; Ling, Jun X; Aaberg, Thomas M; Grossniklaus, Hans E

2003-02-01

To describe two patients with unique lenticular nodular proliferations. Observational case reports. The clinical histories and pathologic findings of two patients with lenticular nodular proliferations were reviewed. One patient with persistent hyperplastic primary vitreous and another patient with trauma developed lenticular nodular proliferations. The nodules were vascularized collections of foamy histiocytes, multinucleated cells, lens capsule, and lens epithelium that had undergone fibrous metaplasia. The lesions were classified as lenticular fibroxanthomatous nodules. A lenticular fibroxanthomatous nodule is a unique clinicopathologic entity that should be differentiated from Soemmerring ring, Elschnig pearl, and other simulating entities such as juvenile xanthogranuloma.

A SAS-based solution to evaluate study design efficiency of phase I pediatric oncology trials via discrete event simulation.

PubMed

Barrett, Jeffrey S; Jayaraman, Bhuvana; Patel, Dimple; Skolnik, Jeffrey M

2008-06-01

Previous exploration of oncology study design efficiency has focused on Markov processes alone (probability-based events) without consideration for time dependencies. Barriers to study completion include time delays associated with patient accrual, inevaluability (IE), time to dose limiting toxicities (DLT) and administrative and review time. Discrete event simulation (DES) can incorporate probability-based assignment of DLT and IE frequency, correlated with cohort in the case of DLT, with time-based events defined by stochastic relationships. A SAS-based solution to examine study efficiency metrics and evaluate design modifications that would improve study efficiency is presented. Virtual patients are simulated with attributes defined from prior distributions of relevant patient characteristics. Study population datasets are read into SAS macros which select patients and enroll them into a study based on the specific design criteria if the study is open to enrollment. Waiting times, arrival times and time to study events are also sampled from prior distributions; post-processing of study simulations is provided within the decision macros and compared across designs in a separate post-processing algorithm. This solution is examined via comparison of the standard 3+3 decision rule relative to the "rolling 6" design, a newly proposed enrollment strategy for the phase I pediatric oncology setting.

Development of a Numerical Method for Patient-Specific Cerebral Circulation Using 1D-0D Simulation of the Entire Cardiovascular System with SPECT Data.

PubMed

Zhang, Hao; Fujiwara, Naoya; Kobayashi, Masaharu; Yamada, Shigeki; Liang, Fuyou; Takagi, Shu; Oshima, Marie

2016-08-01

The detailed flow information in the circle of Willis (CoW) can facilitate a better understanding of disease progression, and provide useful references for disease treatment. We have been developing a one-dimensional-zero-dimensional (1D-0D) simulation method for the entire cardiovascular system to obtain hemodynamics information in the CoW. This paper presents a new method for applying 1D-0D simulation to an individual patient using patient-specific data. The key issue is how to adjust the deviation of physiological parameters, such as peripheral resistance, from literature data when patient-specific geometry is used. In order to overcome this problem, we utilized flow information from single photon emission computed tomography (SPECT) data. A numerical method was developed to optimize physiological parameters by adjusting peripheral cerebral resistance to minimize the difference between the resulting flow rate and the SPECT data in the efferent arteries of the CoW. The method was applied to three cases using different sets of patient-specific data in order to investigate the hemodynamics of the CoW. The resulting flow rates in the afferent arteries were compared to those of the phase-contrast magnetic resonance angiography (PC-MRA) data. Utilization of the SPECT data combined with the PC-MRA data showed a good agreement in flow rates in the afferent arteries of the CoW with those of PC-MRA data for all three cases. The results also demonstrated that application of SPECT data alone could provide the information on the ratios of flow distributions among arteries in the CoW.

A simulation model for determining the optimal size of emergency teams on call in the operating room at night.

PubMed

van Oostrum, Jeroen M; Van Houdenhoven, Mark; Vrielink, Manon M J; Klein, Jan; Hans, Erwin W; Klimek, Markus; Wullink, Gerhard; Steyerberg, Ewout W; Kazemier, Geert

2008-11-01

Hospitals that perform emergency surgery during the night (e.g., from 11:00 pm to 7:30 am) face decisions on optimal operating room (OR) staffing. Emergency patients need to be operated on within a predefined safety window to decrease morbidity and improve their chances of full recovery. We developed a process to determine the optimal OR team composition during the night, such that staffing costs are minimized, while providing adequate resources to start surgery within the safety interval. A discrete event simulation in combination with modeling of safety intervals was applied. Emergency surgery was allowed to be postponed safely. The model was tested using data from the main OR of Erasmus University Medical Center (Erasmus MC). Two outcome measures were calculated: violation of safety intervals and frequency with which OR and anesthesia nurses were called in from home. We used the following input data from Erasmus MC to estimate distributions of all relevant parameters in our model: arrival times of emergency patients, durations of surgical cases, length of stay in the postanesthesia care unit, and transportation times. In addition, surgeons and OR staff of Erasmus MC specified safety intervals. Reducing in-house team members from 9 to 5 increased the fraction of patients treated too late by 2.5% as compared to the baseline scenario. Substantially more OR and anesthesia nurses were called in from home when needed. The use of safety intervals benefits OR management during nights. Modeling of safety intervals substantially influences the number of emergency patients treated on time. Our case study showed that by modeling safety intervals and applying computer simulation, an OR can reduce its staff on call without jeopardizing patient safety.

A cost-effectiveness analysis of "test" versus "treat" patients hospitalized with suspected influenza in Hong Kong.

PubMed

You, Joyce H S; Chan, Eva S K; Leung, Maggie Y K; Ip, Margaret; Lee, Nelson L S

2012-01-01

Seasonal and 2009 H1N1 influenza viruses may cause severe diseases and result in excess hospitalization and mortality in the older and younger adults, respectively. Early antiviral treatment may improve clinical outcomes. We examined potential outcomes and costs of test-guided versus empirical treatment in patients hospitalized for suspected influenza in Hong Kong. We designed a decision tree to simulate potential outcomes of four management strategies in adults hospitalized for severe respiratory infection suspected of influenza: "immunofluorescence-assay" (IFA) or "polymerase-chain-reaction" (PCR)-guided oseltamivir treatment, "empirical treatment plus PCR" and "empirical treatment alone". Model inputs were derived from literature. The average prevalence (11%) of influenza in 2010-2011 (58% being 2009 H1N1) among cases of respiratory infections was used in the base-case analysis. Primary outcome simulated was cost per quality-adjusted life-year (QALY) expected (ICER) from the Hong Kong healthcare providers' perspective. In base-case analysis, "empirical treatment alone" was shown to be the most cost-effective strategy and dominated the other three options. Sensitivity analyses showed that "PCR-guided treatment" would dominate "empirical treatment alone" when the daily cost of oseltamivir exceeded USD18, or when influenza prevalence was <2.5% and the predominant circulating viruses were not 2009 H1N1. Using USD50,000 as the threshold of willingness-to-pay, "empirical treatment alone" and "PCR-guided treatment" were cost-effective 97% and 3% of time, respectively, in 10,000 Monte-Carlo simulations. During influenza epidemics, empirical antiviral treatment appears to be a cost-effective strategy in managing patients hospitalized with severe respiratory infection suspected of influenza, from the perspective of healthcare providers in Hong Kong.

A virtual source model for Monte Carlo simulation of helical tomotherapy.

PubMed

Yuan, Jiankui; Rong, Yi; Chen, Quan

2015-01-08

The purpose of this study was to present a Monte Carlo (MC) simulation method based on a virtual source, jaw, and MLC model to calculate dose in patient for helical tomotherapy without the need of calculating phase-space files (PSFs). Current studies on the tomotherapy MC simulation adopt a full MC model, which includes extensive modeling of radiation source, primary and secondary jaws, and multileaf collimator (MLC). In the full MC model, PSFs need to be created at different scoring planes to facilitate the patient dose calculations. In the present work, the virtual source model (VSM) we established was based on the gold standard beam data of a tomotherapy unit, which can be exported from the treatment planning station (TPS). The TPS-generated sinograms were extracted from the archived patient XML (eXtensible Markup Language) files. The fluence map for the MC sampling was created by incorporating the percentage leaf open time (LOT) with leaf filter, jaw penumbra, and leaf latency contained from sinogram files. The VSM was validated for various geometry setups and clinical situations involving heterogeneous media and delivery quality assurance (DQA) cases. An agreement of < 1% was obtained between the measured and simulated results for percent depth doses (PDDs) and open beam profiles for all three jaw settings in the VSM commissioning. The accuracy of the VSM leaf filter model was verified in comparing the measured and simulated results for a Picket Fence pattern. An agreement of < 2% was achieved between the presented VSM and a published full MC model for heterogeneous phantoms. For complex clinical head and neck (HN) cases, the VSM-based MC simulation of DQA plans agreed with the film measurement with 98% of planar dose pixels passing on the 2%/2 mm gamma criteria. For patient treatment plans, results showed comparable dose-volume histograms (DVHs) for planning target volumes (PTVs) and organs at risk (OARs). Deviations observed in this study were consistent with literature. The VSM-based MC simulation approach can be feasibly built from the gold standard beam model of a tomotherapy unit. The accuracy of the VSM was validated against measurements in homogeneous media, as well as published full MC model in heterogeneous media.

A virtual source model for Monte Carlo simulation of helical tomotherapy

PubMed Central

Yuan, Jiankui; Rong, Yi

2015-01-01

The purpose of this study was to present a Monte Carlo (MC) simulation method based on a virtual source, jaw, and MLC model to calculate dose in patient for helical tomotherapy without the need of calculating phase‐space files (PSFs). Current studies on the tomotherapy MC simulation adopt a full MC model, which includes extensive modeling of radiation source, primary and secondary jaws, and multileaf collimator (MLC). In the full MC model, PSFs need to be created at different scoring planes to facilitate the patient dose calculations. In the present work, the virtual source model (VSM) we established was based on the gold standard beam data of a tomotherapy unit, which can be exported from the treatment planning station (TPS). The TPS‐generated sinograms were extracted from the archived patient XML (eXtensible Markup Language) files. The fluence map for the MC sampling was created by incorporating the percentage leaf open time (LOT) with leaf filter, jaw penumbra, and leaf latency contained from sinogram files. The VSM was validated for various geometry setups and clinical situations involving heterogeneous media and delivery quality assurance (DQA) cases. An agreement of <1% was obtained between the measured and simulated results for percent depth doses (PDDs) and open beam profiles for all three jaw settings in the VSM commissioning. The accuracy of the VSM leaf filter model was verified in comparing the measured and simulated results for a Picket Fence pattern. An agreement of <2% was achieved between the presented VSM and a published full MC model for heterogeneous phantoms. For complex clinical head and neck (HN) cases, the VSM‐based MC simulation of DQA plans agreed with the film measurement with 98% of planar dose pixels passing on the 2%/2 mm gamma criteria. For patient treatment plans, results showed comparable dose‐volume histograms (DVHs) for planning target volumes (PTVs) and organs at risk (OARs). Deviations observed in this study were consistent with literature. The VSM‐based MC simulation approach can be feasibly built from the gold standard beam model of a tomotherapy unit. The accuracy of the VSM was validated against measurements in homogeneous media, as well as published full MC model in heterogeneous media. PACS numbers: 87.53.‐j, 87.55.K‐ PMID:25679157

Contact and photocontact allergy to oxybenzone.

PubMed

Lenique, P; Machet, L; Vaillant, L; Bensaïd, P; Muller, C; Khallouf, R; Lorette, G

1992-03-01

The purpose of this study was to determine the frequency of contact allergy and photocontact allergy to sunscreens. A consecutive series of 54 patients with suspected clinical photosensitivity were assessed. All had the same standardized photobiological investigation from January 1989 to December 1990, including patch tests and photopatch tests with 6 sunscreen agents. Oxybenzone was found to cause 4 cases of allergic contact dermatitis (with photoaggravation in 2), and 3 cases of photocontact dermatitis (13% of patients). This is probably due to the wide distribution of oxybenzone in sunscreens and other cosmetics, 2 patients with polymorphic light eruption and persistent light reactivity, respectively, were regular sunscreen users. Photobiological investigation is necessary to ensure accurate diagnosis, since sunscreen contact or photocontact allergy may simulate other photosensitivity eruptions.

Budget impact analysis of thrombolysis for stroke in Spain: a discrete event simulation model.

PubMed

Mar, Javier; Arrospide, Arantzazu; Comas, Mercè

2010-01-01

Thrombolysis within the first 3 hours after the onset of symptoms of a stroke has been shown to be a cost-effective treatment because treated patients are 30% more likely than nontreated patients to have no residual disability. The objective of this study was to calculate by means of a discrete event simulation model the budget impact of thrombolysis in Spain. The budget impact analysis was based on stroke incidence rates and the estimation of the prevalence of stroke-related disability in Spain and its translation to hospital and social costs. A discrete event simulation model was constructed to represent the flow of patients with stroke in Spain. If 10% of patients with stroke from 2000 to 2015 would receive thrombolytic treatment, the prevalence of dependent patients in 2015 would decrease from 149,953 to 145,922. For the first 6 years, the cost of intervention would surpass the savings. Nevertheless, the number of cases in which patient dependency was avoided would steadily increase, and after 2006 the cost savings would be greater, with a widening difference between the cost of intervention and the cost of nonintervention, until 2015. The impact of thrombolysis on society's health and social budget indicates a net benefit after 6 years, and the improvement in health grows continuously. The validation of the model demonstrates the adequacy of the discrete event simulation approach in representing the epidemiology of stroke to calculate the budget impact.

Acquired simulated brown syndrome following surgical repair of medial orbital wall fracture.

PubMed

Hwang, Jong-uk; Lim, Hyun Taek

2005-03-01

Simulated Brown syndrome is a term applied to a myriad of disorders that cause a Brown syndrome-like motility. We encountered a case of acquired simulated Brown syndrome in a 41-year-old man following surgical repair of fractures of both medial orbital walls. He suffered from diplopia in primary gaze, associated with hypotropia of the affected eye. We performed an ipsilateral recession of the left inferior rectus muscle as a single-stage intraoperative adjustment procedure under topical anesthesia, rather than the direct approach to the superior oblique tendon. Postoperatively, the patient was asymptomatic in all diagnostic gaze positions.

Phase-contrast MRI versus numerical simulation to quantify hemodynamical changes in cerebral aneurysms after flow diverter treatment

PubMed Central

Frolov, Sergey; Prothmann, Sascha; Liepsch, Dieter; Balasso, Andrea; Berg, Philipp; Kaczmarz, Stephan; Kirschke, Jan Stefan

2018-01-01

Cerebral aneurysms are a major risk factor for intracranial bleeding with devastating consequences for the patient. One recently established treatment is the implantation of flow-diverters (FD). Methods to predict their treatment success before or directly after implantation are not well investigated yet. The aim of this work was to quantitatively study hemodynamic parameters in patient-specific models of treated cerebral aneurysms and its correlation with the clinical outcome. Hemodynamics were evaluated using both computational fluid dynamics (CFD) and phase contrast (PC) MRI. CFD simulations and in vitro MRI measurements were done under similar flow conditions and results of both methods were comparatively analyzed. For preoperative and postoperative distribution of hemodynamic parameters, CFD simulations and PC-MRI velocity measurements showed similar results. In both cases where no occlusion of the aneurysm was observed after six months, a flow reduction of about 30-50% was found, while in the clinically successful case with complete occlusion of the aneurysm after 6 months, the flow reduction was about 80%. No vortex was observed in any of the three models after treatment. The results are in agreement with recent studies suggesting that CFD simulations can predict post-treatment aneurysm flow alteration already before implantation of a FD and PC-MRI could validate the predicted hemodynamic changes right after implantation of a FD. PMID:29304062

Driving simulator and neuropsychological [corrected] testing in OSAS before and under CPAP therapy.

PubMed

Orth, M; Duchna, H-W; Leidag, M; Widdig, W; Rasche, K; Bauer, T T; Walther, J W; de Zeeuw, J; Malin, J-P; Schultze-Werninghaus, G; Kotterba, S

2005-11-01

Patients with obstructive sleep apnoea syndrome (OSAS) have an increased car accident rate. Investigations on accident frequency are based on case history, insurance reports and driving simulator studies. The present study combines neuropsychological testing of different attention aspects engaged in driving a car and driving simulation to evaluate a suitable instrument for assessing therapeutic effects of continuous positive airway pressure (CPAP). Driving simulator investigation and neuropsychological testing of alertness, vigilance and divided attention were performed in 31 patients with polysomnographically confirmed OSAS (apnoea-hypopnoea index 24.8+/-21.5.h(-1)) before, and 2 and 42 days after initiation of CPAP. Divided attention and alertness improved significantly during CPAP, whereas vigilance remained unchanged. However, accident frequency (OSAS before therapy: 2.7+/-2.0; 2 days after CPAP: 1.5+/-1.4; 42 days after CPAP: 0.9+/-1.3) and frequency of concentration faults (OSAS before therapy: 12.4+/-5.1; 2 days after CPAP: 6.5+/-3.9; 42 days after CPAP: 4.9+/-3.3) decreased in the simulated driving situation after 2 and 42 days of therapy. There was no relation between accident frequency, concentration faults and daytime sleepiness, as measured by the Epworth Sleepiness Scale, and polysomnographic or neuropsychological findings, respectively. In conclusion, the present results suggest that driving simulation is a possible benchmark parameter of driving performance in obstructive sleep apnoea syndrome patients.

TH-A-18C-04: Ultrafast Cone-Beam CT Scatter Correction with GPU-Based Monte Carlo Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Y; Southern Medical University, Guangzhou; Bai, T

2014-06-15

Purpose: Scatter artifacts severely degrade image quality of cone-beam CT (CBCT). We present an ultrafast scatter correction framework by using GPU-based Monte Carlo (MC) simulation and prior patient CT image, aiming at automatically finish the whole process including both scatter correction and reconstructions within 30 seconds. Methods: The method consists of six steps: 1) FDK reconstruction using raw projection data; 2) Rigid Registration of planning CT to the FDK results; 3) MC scatter calculation at sparse view angles using the planning CT; 4) Interpolation of the calculated scatter signals to other angles; 5) Removal of scatter from the raw projections;more » 6) FDK reconstruction using the scatter-corrected projections. In addition to using GPU to accelerate MC photon simulations, we also use a small number of photons and a down-sampled CT image in simulation to further reduce computation time. A novel denoising algorithm is used to eliminate MC scatter noise caused by low photon numbers. The method is validated on head-and-neck cases with simulated and clinical data. Results: We have studied impacts of photo histories, volume down sampling factors on the accuracy of scatter estimation. The Fourier analysis was conducted to show that scatter images calculated at 31 angles are sufficient to restore those at all angles with <0.1% error. For the simulated case with a resolution of 512×512×100, we simulated 10M photons per angle. The total computation time is 23.77 seconds on a Nvidia GTX Titan GPU. The scatter-induced shading/cupping artifacts are substantially reduced, and the average HU error of a region-of-interest is reduced from 75.9 to 19.0 HU. Similar results were found for a real patient case. Conclusion: A practical ultrafast MC-based CBCT scatter correction scheme is developed. The whole process of scatter correction and reconstruction is accomplished within 30 seconds. This study is supported in part by NIH (1R01CA154747-01), The Core Technology Research in Strategic Emerging Industry, Guangdong, China (2011A081402003)« less

Assessment of disease management of insomnia at community pharmacies through simulated visits in Pakistan.

PubMed

Hussain, Azhar; Ibrahim, Mohamed Izham; Malik, Madeeha

2013-10-01

The study aimed to document the state of insomnia management at community pharmacies in Pakistan. A cross-sectional study was conducted at randomly selected 371 pharmacies in three cities of Pakistan. Simulated patient visits were performed to collect information on case management of insomnia in terms of history taking and patient counseling at community pharmacies. The data was coded, entered and analyzed by using SPSS Version 16. Kruskal-Wallis and Mann Whitney tests (p<0.05) were performed to find out differences. The patients were mainly handled by salesman 83.8% (n=311), by pharmacist 3.5% (n=13) and pharmacy assistants 12.7% (n=47). The mean dispensing time was 1.11 minutes (SD=5.61) with the range of 0.5 - 6 minutes. Of the 371 simulated patients who visited the pharmacies, 72.8% (n=270) subjects were given medicines and 24.3% (n=90) subjects were referred to the doctor for treatment of insomnia. 61.8% (n=193) of the subjects were given benzodiazepines, 35.6% (n=111) antihistamines and 2.6% (n=8) NSAIDs at community pharmacies in the three cities. The mean cost of treatment in case of insomnia was PKR12.7 (SD=10.13, median=10). The disease management of insomnia by community pharmacies in Pakistan is not appropriate. The overall process of history taking, medication counselling and referral practices at community pharmacies either located in rural or urban setting and irrespective of the provider type and location of pharmacies, in the three cities is limited.

SU-F-BRD-02: Application of ARCHERRT-- A GPU-Based Monte Carlo Dose Engine for Radiation Therapy -- to Tomotherapy and Patient-Independent IMRT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, L; Du, X; Liu, T

Purpose: As a module of ARCHER -- Accelerated Radiation-transport Computations in Heterogeneous EnviRonments, ARCHER{sub RT} is designed for RadioTherapy (RT) dose calculation. This paper describes the application of ARCHERRT on patient-dependent TomoTherapy and patient-independent IMRT. It also conducts a 'fair' comparison of different GPUs and multicore CPU. Methods: The source input used for patient-dependent TomoTherapy is phase space file (PSF) generated from optimized plan. For patient-independent IMRT, the open filed PSF is used for different cases. The intensity modulation is simulated by fluence map. The GEANT4 code is used as benchmark. DVH and gamma index test are employed to evaluatemore » the accuracy of ARCHER{sub RT} code. Some previous studies reported misleading speedups by comparing GPU code with serial CPU code. To perform a fairer comparison, we write multi-thread code with OpenMP to fully exploit computing potential of CPU. The hardware involved in this study are a 6-core Intel E5-2620 CPU and 6 NVIDIA M2090 GPUs, a K20 GPU and a K40 GPU. Results: Dosimetric results from ARCHER{sub RT} and GEANT4 show good agreement. The 2%/2mm gamma test pass rates for different clinical cases are 97.2% to 99.7%. A single M2090 GPU needs 50~79 seconds for the simulation to achieve a statistical error of 1% in the PTV. The K40 card is about 1.7∼1.8 times faster than M2090 card. Using 6 M2090 card, the simulation can be finished in about 10 seconds. For comparison, Intel E5-2620 needs 507∼879 seconds for the same simulation. Conclusion: We successfully applied ARCHER{sub RT} to Tomotherapy and patient-independent IMRT, and conducted a fair comparison between GPU and CPU performance. The ARCHER{sub RT} code is both accurate and efficient and may be used towards clinical applications.« less

Teaching undergraduate nursing students critical thinking: An innovative informatics strategy.

PubMed

Warren, Judith J; Connors, Helen R; Weaver, Charlotte; Simpson, Roy

2006-01-01

Simulated e-Health Delivery System (SEEDS) uses a clinical information system (CIS) to teach students how to process data from virtual patient case studies and work with information technology. SEEDS was developed in response to the Institute of Medicine recommendation that students be taught about information systems in order to improve quality patient care and reduce errors. Curriculum implications, implementation of the system, and technology challenges are discussed.

Distance Learning Can Be as Effective as Traditional Learning for Medical Students in the Initial Assessment of Trauma Patients.

PubMed

Farahmand, Shervin; Jalili, Ebrahim; Arbab, Mona; Sedaghat, Mojtaba; Shirazi, Mandana; Keshmiri, Fatemeh; Azizpour, Arsalan; Valadkhani, Somayeh; Bagheri-Hariri, Shahram

2016-09-01

Distance learning is expanding and replacing the traditional academic medical settings. Managing trauma patients seems to be a prerequisite skill for medical students. This study has been done to evaluate the efficiency of distance learning on performing the initial assessment and management in trauma patients, compared with the traditional learning among senior medical students. One hundred and twenty senior medical students enrolled in this single-blind quasi-experimental study and were equally divided into the experimental (distance learning) and control group (traditional learning). All participants did a written MCQ before the study. The control group attended a workshop with a 50-minute lecture on initial management of trauma patients and a case simulation scenario followed by a hands-on session. On the other hand, the experimental group was given a DVD with a similar 50-minute lecture and a case simulation scenario, and they also attended a hands-on session to practice the skills. Both groups were evaluated by a trauma station in an objective structured clinical examination (OSCE) after a month. The performance in the experimental group was statistically better (P=0.001) in OSCE. Distance learning seems to be an appropriate adjunct to traditional learning.

An exploratory examination of medical gas booms versus traditional headwalls in intensive care unit design.

PubMed

Pati, Debajyoti; Evans, Jennie; Waggener, Laurie; Harvey, Tom

2008-01-01

Should power, medical gases, and monitoring and communications systems be located in a headwall or a ceiling-mounted boom in intensive care unit (ICU) rooms? Often, only the financial costs could be determined for the options, whereas data regarding its potential influence on teamwork, safety, and efficiency are lacking. Hence, purchase decisions are more arbitrary than evidence based. This study simulated care delivery in settings with a traditional headwall and a ceiling boom. Observed were the way the following elements were managed and the extent either system affected flexibility, ergonomics, and teamwork: tubing for intravenous fluids, medical gases, and suction drainage; monitoring leads and equipment power cords; and the medical equipment itself. Simulation runs involving 6 scenarios were conducted with the voluntary participation of 2 physicians, 2 nurse practitioners, 2 respiratory therapists, and 4 registered nurses at a children's tertiary care center in December 2007. Analysis suggests that booms have an advantage over headwalls in case of high-acuity ICU patients and when procedures are performed inside patient rooms. However, in case of lower-acuity ICU patients, as well as when procedures are not typically conducted in the patient room, booms may not provide a proportionate level of advantage when compared with the additional cost involved in its procurement.

Ordering Molecular Genetic Tests and Reporting Results

PubMed Central

Lubin, Ira M.; Caggana, Michele; Constantin, Carolyn; Gross, Susan J.; Lyon, Elaine; Pagon, Roberta A.; Trotter, Tracy L.; Wilson, Jean Amos; McGovern, Margaret M.

2008-01-01

Previous studies have suggested that patient care may be compromised as a consequence of poor communication between clinicians and laboratory professionals in cases in which molecular genetic test results are reported. To understand better the contributing factors to such compromised care, we investigated both pre- and postanalytical processes using cystic fibrosis mutation analysis as our model. We found that although the majority of test requisition forms requested patient/family information that was necessary for the proper interpretation of test results, in many cases, these data were not provided by the individuals filling out the forms. We found instances in which result reports for simulated diagnostic testing described individuals as carriers where only a single mutation was found with no comment pertaining to a diagnosis of cystic fibrosis. Similarly, reports based on simulated scenarios for carrier testing were problematic when no mutations were identified, and the patient's race/ethnicity and family history were not discussed in reference to residual risk of disease. Remarkably, a pilot survey of obstetrician-gynecologists revealed that office staff, including secretaries, often helped order genetic tests and reported test results to patients, raising questions about what efforts are undertaken to ensure personnel competency. These findings are reviewed in light of what efforts should be taken to improve the quality of test-ordering and result-reporting practices. PMID:18669879

The role of patient simulation and incident reporting in the development and evaluation of medical devices and the training of their users.

PubMed

Dieckmann, P; Rall, M; Ostergaard, D

2009-01-01

We describe how simulation and incident reporting can be used in combination to make the interaction between people, (medical) technology and organisation safer for patients and users. We provide the background rationale for our conceptual ideas and apply the concepts to the analysis of an actual incident report. Simulation can serve as a laboratory to analyse such cases and to create relevant and effective training scenarios based on such analyses. We will describe a methodological framework for analysing simulation scenarios in a way that allows discovering and discussing mismatches between conceptual models of the device design and mental models users hold about the device and its use. We further describe how incident reporting systems can be used as one source of data to conduct the necessary needs analyses - both for training and further needs for closer analysis of specific devices or some of their special features or modes during usability analyses.

Patient-specific biomechanical model of hypoplastic left heart to predict post-operative cardio-circulatory behaviour.

PubMed

Cutrì, Elena; Meoli, Alessio; Dubini, Gabriele; Migliavacca, Francesco; Hsia, Tain-Yen; Pennati, Giancarlo

2017-09-01

Hypoplastic left heart syndrome is a complex congenital heart disease characterised by the underdevelopment of the left ventricle normally treated with a three-stage surgical repair. In this study, a multiscale closed-loop cardio-circulatory model is created to reproduce the pre-operative condition of a patient suffering from such pathology and virtual surgery is performed. Firstly, cardio-circulatory parameters are estimated using a fully closed-loop cardio-circulatory lumped parameter model. Secondly, a 3D standalone FEA model is build up to obtain active and passive ventricular characteristics and unloaded reference state. Lastly, the 3D model of the single ventricle is coupled to the lumped parameter model of the circulation obtaining a multiscale closed-loop pre-operative model. Lacking any information on the fibre orientation, two cases were simulated: (i) fibre distributed as in the physiological right ventricle and (ii) fibre as in the physiological left ventricle. Once the pre-operative condition is satisfactorily simulated for the two cases, virtual surgery is performed. The post-operative results in the two cases highlighted similar hemodynamic behaviour but different local mechanics. This finding suggests that the knowledge of the patient-specific fibre arrangement is important to correctly estimate the single ventricle's working condition and consequently can be valuable to support clinical decision. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Virtual planning for craniomaxillofacial surgery--7 years of experience.

PubMed

Adolphs, Nicolai; Haberl, Ernst-Johannes; Liu, Weichen; Keeve, Erwin; Menneking, Horst; Hoffmeister, Bodo

2014-07-01

Contemporary computer-assisted surgery systems more and more allow for virtual simulation of even complex surgical procedures with increasingly realistic predictions. Preoperative workflows are established and different commercially software solutions are available. Potential and feasibility of virtual craniomaxillofacial surgery as an additional planning tool was assessed retrospectively by comparing predictions and surgical results. Since 2006 virtual simulation has been performed in selected patient cases affected by complex craniomaxillofacial disorders (n = 8) in addition to standard surgical planning based on patient specific 3d-models. Virtual planning could be performed for all levels of the craniomaxillofacial framework within a reasonable preoperative workflow. Simulation of even complex skeletal displacements corresponded well with the real surgical result and soft tissue simulation proved to be helpful. In combination with classic 3d-models showing the underlying skeletal pathology virtual simulation improved planning and transfer of craniomaxillofacial corrections. Additional work and expenses may be justified by increased possibilities of visualisation, information, instruction and documentation in selected craniomaxillofacial procedures. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Digital Tools to Enhance Clinical Reasoning.

PubMed

Manesh, Reza; Dhaliwal, Gurpreet

2018-05-01

Physicians can improve their diagnostic acumen by adopting a simulation-based approach to analyzing published cases. The tight coupling of clinical problems and their solutions affords physicians the opportunity to efficiently upgrade their illness scripts (structured knowledge of a specific disease) and schemas (structured frameworks for common problems). The more times clinicians practice accessing and applying those knowledge structures through published cases, the greater the odds that they will have an enhanced approach to similar patient-cases in the future. This article highlights digital resources that increase the number of cases a clinician experiences and learns from. Copyright © 2017 Elsevier Inc. All rights reserved.

[The Einstein sign].

PubMed

Treska, V

2003-02-01

Untreated rupture of an aneurysm of the abdominal aorta is fatal in almost 100% of the patients. In the majority of cases the assessment of a correct, early diagnosis is simple (hypotension, backache, abdominal pain, pulsating resistance in the abdomen) and makes a prompt surgical or endovascular operation possible. In some instances however rupture of aneurysms of the abdominal aorta simulates other clinical conditions (acute cholecystitis, acute diverculitis of the sigmoid) which may delay the correct diagnosis and reduce the patient's chance of survival. The author describes, based on historical documents, the treacherous course of the disease in the scientific genius Albert Einstein where rupture of an aneurysm simulated acute cholecystitis, and in the world literature this symptomatology was subsequently described as Einstein's sign.

Structured Communication: Teaching Delivery of Difficult News with Simulated Resuscitations in an Emergency Medicine Clerkship

PubMed Central

Lamba, Sangeeta; Nagurka, Roxanne; Offin, Michael; Scott, Sandra R.

2015-01-01

Introduction The objective is to describe the implementation and outcomes of a structured communication module used to supplement case-based simulated resuscitation training in an emergency medicine (EM) clerkship. Methods We supplemented two case-based simulated resuscitation scenarios (cardiac arrest and blunt trauma) with role-play in order to teach medical students how to deliver news of death and poor prognosis to family of the critically ill or injured simulated patient. Quantitative outcomes were assessed with pre and post-clerkship surveys. Secondarily, students completed a written self-reflection (things that went well and why; things that did not go well and why) to further explore learner experiences with communication around resuscitation. Qualitative analysis identified themes from written self-reflections. Results A total of 120 medical students completed the pre and post-clerkship surveys. Majority of respondents reported that they had witnessed or role-played the delivery of difficult news, but only few had real-life experience of delivering news of death (20/120, 17%) and poor prognosis (34/120, 29%). This communication module led to statistically significant increased scores for comfort, confidence, and knowledge with communicating difficult news of death and poor prognosis. Pre-post scores increased for those agreeing with statements (somewhat/very much) for delivery of news of poor prognosis: comfort 69% to 81%, confidence 66% to 81% and knowledge 76% to 90% as well as for statements regarding delivery of news of death: comfort 52% to 68%, confidence 57% to 76% and knowledge 76% to 90%. Respondents report that patient resuscitations (simulated and/or real) generated a variety of strong emotional responses such as anxiety, stress, grief and feelings of loss and failure. Conclusion A structured communication module supplements simulated resuscitation training in an EM clerkship and leads to a self-reported increase in knowledge, comfort, and competence in communicating difficult news of death and poor prognosis to family. Educators may need to seek ways to address the strong emotions generated in learners with real and simulated patient resuscitations. PMID:25834685

A study on the predictability of acute lymphoblastic leukaemia response to treatment using a hybrid oncosimulator.

PubMed

Ouzounoglou, Eleftherios; Kolokotroni, Eleni; Stanulla, Martin; Stamatakos, Georgios S

2018-02-06

Efficient use of Virtual Physiological Human (VPH)-type models for personalized treatment response prediction purposes requires a precise model parameterization. In the case where the available personalized data are not sufficient to fully determine the parameter values, an appropriate prediction task may be followed. This study, a hybrid combination of computational optimization and machine learning methods with an already developed mechanistic model called the acute lymphoblastic leukaemia (ALL) Oncosimulator which simulates ALL progression and treatment response is presented. These methods are used in order for the parameters of the model to be estimated for retrospective cases and to be predicted for prospective ones. The parameter value prediction is based on a regression model trained on retrospective cases. The proposed Hybrid ALL Oncosimulator system has been evaluated when predicting the pre-phase treatment outcome in ALL. This has been correctly achieved for a significant percentage of patient cases tested (approx. 70% of patients). Moreover, the system is capable of denying the classification of cases for which the results are not trustworthy enough. In that case, potentially misleading predictions for a number of patients are avoided, while the classification accuracy for the remaining patient cases further increases. The results obtained are particularly encouraging regarding the soundness of the proposed methodologies and their relevance to the process of achieving clinical applicability of the proposed Hybrid ALL Oncosimulator system and VPH models in general.

Interventional radiology virtual simulator for liver biopsy.

PubMed

Villard, P F; Vidal, F P; ap Cenydd, L; Holbrey, R; Pisharody, S; Johnson, S; Bulpitt, A; John, N W; Bello, F; Gould, D

2014-03-01

Training in Interventional Radiology currently uses the apprenticeship model, where clinical and technical skills of invasive procedures are learnt during practice in patients. This apprenticeship training method is increasingly limited by regulatory restrictions on working hours, concerns over patient risk through trainees' inexperience and the variable exposure to case mix and emergencies during training. To address this, we have developed a computer-based simulation of visceral needle puncture procedures. A real-time framework has been built that includes: segmentation, physically based modelling, haptics rendering, pseudo-ultrasound generation and the concept of a physical mannequin. It is the result of a close collaboration between different universities, involving computer scientists, clinicians, clinical engineers and occupational psychologists. The technical implementation of the framework is a robust and real-time simulation environment combining a physical platform and an immersive computerized virtual environment. The face, content and construct validation have been previously assessed, showing the reliability and effectiveness of this framework, as well as its potential for teaching visceral needle puncture. A simulator for ultrasound-guided liver biopsy has been developed. It includes functionalities and metrics extracted from cognitive task analysis. This framework can be useful during training, particularly given the known difficulties in gaining significant practice of core skills in patients.

Image- and model-based surgical planning in otolaryngology.

PubMed

Korves, B; Klimek, L; Klein, H M; Mösges, R

1995-10-01

Preoperative evaluation of any operating field is essential for the preparation of surgical procedures. The relationship between pathology and adjacent structures, and anatomically dangerous sites need to be analyzed for the determination of intraoperative action. For the simulation of surgery using three-dimensional imaging or individually manufactured plastic patient models, the authors have worked out different procedures. A total of 481 surgical interventions in the maxillofacial region, paranasal sinuses, orbit, and the anterior and middle skull base, in addition to neurotologic procedures were presurgically simulated using three-dimensional imaging and image manipulation. An intraoperative simulation device, part of the Aachen Computer-Assisted Surgery System, had been applied in 407 of these cases. In seven patients, stereolithography was used to create plastic patient models for the preparation of reconstructive surgery and prostheses fabrication. The disadvantages of this process include time and cost; however, the advantages included (1) a better understanding of the anatomic relationships, (2) the feasibility of presurgical simulation of the prevailing procedure, (3) an improved intraoperative localization accuracy, (4) prostheses fabrication in reconstructive procedures with an approach to more accuracy, (5) permanent recordings for future requirements or reconstructions, and (6) improved residency education.

MO-DE-210-07: Investigation of Treatment Interferences of a Novel Robotic Ultrasound Radiotherapy Guidance System with Clinical VMAT Plans for Liver SBRT Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, R; Bruder, R; Schweikard, A

Purpose: To evaluate the proportion of liver SBRT cases in which robotic ultrasound image guidance concurrent with beam delivery can be deployed without interfering with clinically used VMAT beam configurations. Methods: A simulation environment incorporating LINAC, couch, planning CT, and robotic ultrasound guidance hardware was developed. Virtual placement of the robotic ultrasound hardware was guided by a target visibility map rendered on the CT surface. The map was computed on GPU by using the planning CT to simulate ultrasound propagation and attenuation along rays connecting skin surface points to a rasterized imaging target. The visibility map was validated in amore » prostate phantom experiment by capturing live ultrasound images of the prostate from different phantom locations. In 20 liver SBRT patients treated with VMAT, the simulation environment was used to place the robotic hardware and ultrasound probe at imaging locations indicated on the visibility map. Imaging targets were either entire PTV (range 5.9–679.5 ml) or entire GTV (range 0.9–343.4 ml). Presence or absence of mechanical collisions with LINAC, couch, and patient body as well as interferences with treated beams were recorded. Results: For PTV targets, robotic ultrasound guidance without mechanical collision was possible in 80% of the cases and guidance without beam interference was possible in 60% of the cases. For the smaller GTV targets, these proportions were 95% and 85% correspondingly. GTV size (1/20), elongated shape (1/20), and depth (1/20) were the main factors limiting the availability of non-interfering imaging positions. Conclusion: This study indicates that for VMAT liver SBRT, robotic ultrasound tracking of a relevant internal target would be possible in 85% of cases while using treatment plans currently deployed in the clinic. With beam re-planning in accordance with the presence of robotic ultrasound guidance, intra-fractional ultrasound guidance may be an option for 95% of the liver SBRT cases. This project was funded by NIH Grant R41CA174089.« less

The Clinical Health Economics System Simulation (CHESS): a teaching tool for systems- and practice-based learning.

PubMed

Voss, John D; Nadkarni, Mohan M; Schectman, Joel M

2005-02-01

Academic medical centers face barriers to training physicians in systems- and practice-based learning competencies needed to function in the changing health care environment. To address these problems, at the University of Virginia School of Medicine the authors developed the Clinical Health Economics System Simulation (CHESS), a computerized team-based quasi-competitive simulator to teach the principles and practical application of health economics. CHESS simulates treatment costs to patients and society as well as physician reimbursement. It is scenario based with residents grouped into three teams, each team playing CHESS using differing (fee-for-service or capitated) reimbursement models. Teams view scenarios and select from two or three treatment options that are medically justifiable yet have different potential cost implications. CHESS displays physician reimbursement and patient and societal costs for each scenario as well as costs and income summarized across all scenarios extrapolated to a physician's entire patient panel. The learners are asked to explain these findings and may change treatment options and other variables such as panel size and case mix to conduct sensitivity analyses in real time. Evaluations completed in 2003 by 68 (94%) CHESS resident and faculty participants at 19 U.S. residency programs preferred CHESS to a traditional lecture-and-discussion format to learn about medical decision making, physician reimbursement, patient costs, and societal costs. Ninety-eight percent reported increased knowledge of health economics after viewing the simulation. CHESS demonstrates the potential of computer simulation to teach health economics and other key elements of practice- and systems-based competencies.

Cutaneous protothecosis - Case report*

PubMed Central

da Silva, Pâmela Craveiro Gomes; Silva, Sabrina Beirão da Costa e; Lima, Ricardo Barbosa; D'Acri, Antonio Macedo; Lupi, Omar; Martins, Carlos José

2013-01-01

Cutaneous protothecosis is a rare infection caused by achlorophyllic algae of the genus Prototheca. The lesions usually occur on exposed areas, related with trauma, in immunocompromised patients. The most common clinical presentation is a vesicobullous and ulcerative lesion with pustules and scabs, simulating bacterial, fungal or herpetic infections or eczema. The diagnosis is determined by agent identification through histopathology, culture and the carbohydrates assimilation test. The finding of morula-like spherules is characteristic of Prototheca sp. Its rarity and non-specific clinical aspect may difficult the disease diagnosis. We report a case of a diabetic patient, in chronic use of systemic corticosteroids, that developed a skin lesion after trauma to the right leg. PMID:24346914

Cutaneous protothecosis--case report.

PubMed

Silva, Pâmela Craveiro Gomes da; Costa e Silva, Sabrina Beirão da; Lima, Ricardo Barbosa; D'Acri, Antonio Macedo; Lupi, Omar; Martins, Carlos José

2013-01-01

Cutaneous protothecosis is a rare infection caused by achlorophyllic algae of the genus Prototheca. The lesions usually occur on exposed areas, related with trauma, in immunocompromised patients. The most common clinical presentation is a vesicobullous and ulcerative lesion with pustules and scabs, simulating bacterial, fungal or herpetic infections or eczema. The diagnosis is determined by agent identification through histopathology, culture and the carbohydrates assimilation test. The finding of morula-like spherules is characteristic of Prototheca sp. Its rarity and non-specific clinical aspect may difficult the disease diagnosis. We report a case of a diabetic patient, in chronic use of systemic corticosteroids, that developed a skin lesion after trauma to the right leg.

Impact of an All-or-Nothing Assignment Requirement under Medicare

PubMed Central

Mitchell, Janet B.; Cromwell, Jerry

1983-01-01

In an effort to raise assignment rates, some policymakers have considered dropping Medicare's case-by-case assignment option. Physicians would have to decide whether to accept all of their patients on assignment, or none of them. In a 1976 national survey, over two-thirds of the physicians stated they would take none of their patients on assignment if forced to choose. Simulation analysis showed that in that event, assignment rates nationwide would fall almost 10 percent. The mean supply of assigned visits would actually increase 11 percent for general practitioners, while decreasing 12-25 percent for general surgeons, internists, and obstetricians/gynecologists. PMID:10310000

Priority Queuing Models for Hospital Intensive Care Units and Impacts to Severe Case Patients

PubMed Central

Hagen, Matthew S.; Jopling, Jeffrey K; Buchman, Timothy G; Lee, Eva K.

2013-01-01

This paper examines several different queuing models for intensive care units (ICU) and the effects on wait times, utilization, return rates, mortalities, and number of patients served. Five separate intensive care units at an urban hospital are analyzed and distributions are fitted for arrivals and service durations. A system-based simulation model is built to capture all possible cases of patient flow after ICU admission. These include mortalities and returns before and after hospital exits. Patients are grouped into 9 different classes that are categorized by severity and length of stay (LOS). Each queuing model varies by the policies that are permitted and by the order the patients are admitted. The first set of models does not prioritize patients, but examines the advantages of smoothing the operating schedule for elective surgeries. The second set analyzes the differences between prioritizing admissions by expected LOS or patient severity. The last set permits early ICU discharges and conservative and aggressive bumping policies are contrasted. It was found that prioritizing patients by severity considerably reduced delays for critical cases, but also increased the average waiting time for all patients. Aggressive bumping significantly raised the return and mortality rates, but more conservative methods balance quality and efficiency with lowered wait times without serious consequences. PMID:24551379

Biofeedback defaecation training for anismus.

PubMed

Lestàr, B; Penninckx, F; Kerremans, R

1991-11-01

Anismus, paradoxical external sphincter function, spastic pelvic floor syndrome, rectoanal dysnergia, abdomino-levator incoordination for abdominopelvic asychronism, are all due to paradoxical contraction of the striated sphincter apparatus during voiding and is characterised by prolonged and excessive straining at stool. Biofeedback is the treatment of choice and has to be introduced at an early stage. We present the results of an ambulatory approach based on the integration of simulated balloon defaecation with small (50 ml) as well as constant rectal sensation volume, defaecometry and anal manometry. The pathophysiology visualised by the patient's own anorectal pressure recordings on the screen of a personal computer is explained and corrected. Sixteen patients were treated and followed for at least 1 year. Manometric data were normal except for an increased minimum residual pressure and rectal compliance. Nine patients could not evacuate a 50 ml bolus initially. Simulated defaecation became possible in seven out of these nine patients when the bolus was increased up to the individual constant rectal sensation volume. Two patients could not evacuate this volume either, while defaecation was made much less laborious in the other seven patients. Paradoxical contraction was immediately corrected in 7/16 cases. Also, as an immediate, objective benefit of a single training session, improved defaecation of a 50 ml bolus was observed in 11 patients. This effect was preserved after 6 weeks in nine cases; symptomatic recurrence did not occur in these patients during follow-up. This method of defaecation training has many advantages as compared with sphincter training using EMG electrodes eventually performed in the absence of a desire to defaecate or in lying position.(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of the Incubation Period for Invasive Listeriosis.

PubMed

Angelo, Kristina M; Jackson, Kelly A; Wong, Karen K; Hoekstra, Robert M; Jackson, Brendan R

2016-12-01

We characterized incubation periods among outbreak-associated listeriosis cases, using a simulation model to account for patients with multiple exposure dates. The median was 11 days; 90% of cases occurred within 28 days, and incubation periods varied by clinical manifestation. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Preoperative easily misdiagnosed telangiectatic osteosarcoma: clinical–radiologic–pathologic correlations

PubMed Central

Gao, Zhen-Hua; Yin, Jun-Qiang; Liu, Da-Wei; Meng, Quan-Fei

2013-01-01

Abstract Purpose: To describe the clinical, imaging, and pathologic characteristics and diagnostic methods of telangiectatic osteosarcoma (TOS) for improving the diagnostic level. Materials and methods: The authors retrospectively reviewed patient demographics, serum alkaline phosphatase (AKP) levels, preoperative biopsy pathologic reports, pathologic materials, imaging findings, and treatment outcomes from 26 patients with TOS. Patient images from radiography (26 cases) and magnetic resonance (MR) imaging (22 cases) were evaluated by 3 authors in consensus for intrinsic characteristics. There were 15 male and 11 female patients in the study, with an age of 9–32 years (mean age 15.9 years). Results: Eighteen of 26 patients died of lung metastases within 5 years of follow-up. The distal femur was affected more commonly (14 cases, 53.8%). Regarding serum AKP, normal (8 cases) or mildly elevated (18 cases) levels were found before preoperative chemotherapy. Radiographs showed geographic bone lysis without sclerotic margin (26 cases), cortical destruction (26 cases), periosteal new bone formation (24 cases), soft-tissue mass (23 cases), and matrix mineralization (4 cases). The aggressive radiographic features of TOS simulated the appearance of conventional high-grade intramedullary osteosarcoma, though different from aneurysmal bone cyst. MR images demonstrated multiple big (16 cases) or small (6 cases) cystic spaces, fluid-fluid levels (14 cases), soft-tissue mass (22 cases), and thick peripheral and septal enhancement (22 cases). Nine of 26 cases were misdiagnosed as aneurysmal bone cysts by preoperative core-needle biopsy, owing to the absence of viable high-grade sarcomatous cells in the small tissue samples. Conclusion: The aggressive growth pattern with occasional matrix mineralization, and multiple big or small fluid-filled cavities with thick peripheral, septal, and nodular tissue surrounding the fluid-filled cavities are characteristic imaging features of TOS, and these features are helpful in making the correct preoperative diagnosis of TOS. PMID:24334494

High-fidelity hybrid simulation of allergic emergencies demonstrates improved preparedness for office emergencies in pediatric allergy clinics.

PubMed

Kennedy, Joshua L; Jones, Stacie M; Porter, Nicholas; White, Marjorie L; Gephardt, Grace; Hill, Travis; Cantrell, Mary; Nick, Todd G; Melguizo, Maria; Smith, Chris; Boateng, Beatrice A; Perry, Tamara T; Scurlock, Amy M; Thompson, Tonya M

2013-01-01

Simulation models that used high-fidelity mannequins have shown promise in medical education, particularly for cases in which the event is uncommon. Allergy physicians encounter emergencies in their offices, and these can be the source of much trepidation. To determine if case-based simulations with high-fidelity mannequins are effective in teaching and retention of emergency management team skills. Allergy clinics were invited to Arkansas Children's Hospital Pediatric Understanding and Learning through Simulation Education center for a 1-day workshop to evaluate skills concerning the management of allergic emergencies. A Clinical Emergency Preparedness Team Performance Evaluation was developed to evaluate the competence of teams in several areas: leadership and/or role clarity, closed-loop communication, team support, situational awareness, and scenario-specific skills. Four cases, which focus on common allergic emergencies, were simulated by using high-fidelity mannequins and standardized patients. Teams were evaluated by multiple reviewers by using video recording and standardized scoring. Ten to 12 months after initial training, an unannounced in situ case was performed to determine retention of the skills training. Clinics showed significant improvements for role clarity, teamwork, situational awareness, and scenario-specific skills during the 1-day workshop (all P < .003). Follow-up in situ scenarios 10-12 months later demonstrated retention of skills training at both clinics (all P ≤ .004). Clinical Emergency Preparedness Team Performance Evaluation scores demonstrated improved team management skills with simulation training in office emergencies. Significant recall of team emergency management skills was demonstrated months after the initial training. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Arthroscopic Shoulder Surgical Simulation Training Curriculum: Transfer Reliability and Maintenance of Skill Over Time.

PubMed

Dunn, John C; Belmont, Philip J; Lanzi, Joseph; Martin, Kevin; Bader, Julia; Owens, Brett; Waterman, Brian R

2015-01-01

Surgical education is evolving as work hour constraints limit the exposure of residents to the operating room. Potential consequences may include erosion of resident education and decreased quality of patient care. Surgical simulation training has become a focus of study in an effort to counter these challenges. Previous studies have validated the use of arthroscopic surgical simulation programs both in vitro and in vivo. However, no study has examined if the gains made by residents after a simulation program are retained after a period away from training. In all, 17 orthopedic surgery residents were randomized into simulation or standard practice groups. All subjects were oriented to the arthroscopic simulator, a 14-point anatomic checklist, and Arthroscopic Surgery Skill Evaluation Tool (ASSET). The experimental group received 1 hour of simulation training whereas the control group had no additional training. All subjects performed a recorded, diagnostic arthroscopy intraoperatively. These videos were scored by 2 blinded, fellowship-trained orthopedic surgeons and outcome measures were compared within and between the groups. After 1 year in which neither group had exposure to surgical simulation training, all residents were retested intraoperatively and scored in the exact same fashion. Individual surgical case logs were reviewed and surgical case volume was documented. There was no difference between the 2 groups after initial simulation testing and there was no correlation between case volume and initial scores. After training, the simulation group improved as compared with baseline in mean ASSET (p = 0.023) and mean time to completion (p = 0.01). After 1 year, there was no difference between the groups in any outcome measurements. Although individual technical skills can be cultivated with surgical simulation training, these advancements can be lost without continued education. It is imperative that residency programs implement a simulation curriculum and continue to train throughout the academic year. Published by Elsevier Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pollard, J; Prajapati, S; Gao, S

Purpose: To evaluate correlation between the reproducibility of tumor position under feedback guided voluntary deep inspiration breath hold gating at simulation and at treatment. Methods: All patients treated with breath hold (BH) have 3-6 BH CTs taken at simulation (sim). In addition, if the relationship between the tumor and nearby bony anatomy on treatment BH CT(or CBCT) is found to be greater than 5 mm different at treatment than it was at sim, a repeat BH CT is taken before treatment. We retrospectively analyzed the sim CTs for 19 patients who received BH SBRT lung treatments and had repeat BHmore » CT on treatment. We evaluated the reproducibility of the tumor position during the simulation CTs and compared this to the reproducibility of the tumor position on the repeat treatment CT with our in-house CT alignment software (CT-Assisted Targeting for Radiotherapy). Results: Comparing the tumor position for multiple simulation BH CTs, we calculated: maximum difference (max) = 0.69cm; average difference (x) = 0.28cm; standard deviation (σ) = 0.18cm. Comparing the repeat BH CBCTs on treatment days we calculated: max = 0.44cm; x = 0.16cm; σ = 0.22cm. We also found that for 95% of our BH cases, the absolute variation in tumor position within the same imaging day was within 5mm of the range at the time of simulation and treatment. We found that 75% of the BH cases had less residual tumor motion on treatment days than at simulation. Conclusion: This suggests that a GTV contour based upon the residual tumor motion in multiple BH datasets plus 2 mm margin should be sufficient to cover the full range of residual tumor motion on treatment days.« less

Homozygosity mapping on a single patient: identification of homozygous regions of recent common ancestry by using population data.

PubMed

Zhang, Lu; Yang, Wanling; Ying, Dingge; Cherny, Stacey S; Hildebrandt, Friedhelm; Sham, Pak Chung; Lau, Yu Lung

2011-03-01

Homozygosity mapping has played an important role in detecting recessive mutations using families of consanguineous marriages. However, detection of regions identical and homozygosity by descent (HBD) when family data are not available, or when relationships are unknown, is still a challenge. Making use of population data from high-density SNP genotyping may allow detection of regions HBD from recent common founders in singleton patients without genealogy information. We report a novel algorithm that detects such regions by estimating the population haplotype frequencies (HF) for an entire homozygous region. We also developed a simulation method to evaluate the probability of HBD and linkage to disease for a homozygous region by examining the best regions in unaffected controls from the host population. The method can be applied to diseases of Mendelian inheritance but can also be extended to complex diseases to detect rare founder mutations that affect a very small number of patients using either multiplex families or sporadic cases. Testing of the method on both real cases (singleton affected) and simulated data demonstrated its superb sensitivity and robustness under genetic heterogeneity. © 2011 Wiley-Liss, Inc.

Immediate balloon deflation for prevention of persistent phrenic nerve palsy during pulmonary vein isolation by balloon cryoablation.

PubMed

Ghosh, Justin; Sepahpour, Ali; Chan, Kim H; Singarayar, Suresh; McGuire, Mark A

2013-05-01

Persistent phrenic nerve palsy is the most frequent complication of cryoballoon ablation for atrial fibrillation and can be disabling. To describe a technique-immediate balloon deflation (IBD)-for the prevention of persistent phrenic nerve palsy, provide data for its use, and describe in vitro simulations performed to investigate the effect of IBD on the atrium and pulmonary vein. Cryoballoon procedures for atrial fibrillation were analyzed retrospectively (n = 130). IBD was performed in patients developing phrenic nerve dysfunction (n = 22). In vitro simulations were performed by using phantoms. No adverse events occurred, and all patients recovered normal phrenic nerve function before leaving the procedure room. No patient developed persistent phrenic nerve palsy. The mean cryoablation time to onset of phrenic nerve dysfunction was 144 ± 64 seconds. Transient phrenic nerve dysfunction was seen more frequently with the 23-mm balloon than with the 28-mm balloon (11 of 39 cases vs 11 of 81 cases; P = .036). Balloon rewarming was faster following IBD. The time to return to 0 and 20° C was shorter in the IBD group (6.7 vs 8.9 seconds; P = .007 and 16.7 vs 37.6 seconds; P<.0001). In vitro simulations confirmed that IBD caused more rapid tissue warming (time to 0°C, 14.0 ± 3.4 seconds vs 46.0 ± 8.1; P = .0001) and is unlikely to damage the atrium or pulmonary vein. IBD results in more rapid tissue rewarming, causes no adverse events, and appears to prevent persistent phrenic nerve palsy. Simulations suggest that IBD is unlikely to damage the atrium or pulmonary vein. Copyright © 2013 Heart Rhythm Society. All rights reserved.

Wall Shear Stress Distribution in a Patient-Specific Cerebral Aneurysm Model using Reduced Order Modeling

NASA Astrophysics Data System (ADS)

Han, Suyue; Chang, Gary Han; Schirmer, Clemens; Modarres-Sadeghi, Yahya

2016-11-01

We construct a reduced-order model (ROM) to study the Wall Shear Stress (WSS) distributions in image-based patient-specific aneurysms models. The magnitude of WSS has been shown to be a critical factor in growth and rupture of human aneurysms. We start the process by running a training case using Computational Fluid Dynamics (CFD) simulation with time-varying flow parameters, such that these parameters cover the range of parameters of interest. The method of snapshot Proper Orthogonal Decomposition (POD) is utilized to construct the reduced-order bases using the training CFD simulation. The resulting ROM enables us to study the flow patterns and the WSS distributions over a range of system parameters computationally very efficiently with a relatively small number of modes. This enables comprehensive analysis of the model system across a range of physiological conditions without the need to re-compute the simulation for small changes in the system parameters.

Using discrete event computer simulation to improve patient flow in a Ghanaian acute care hospital.

PubMed

Best, Allyson M; Dixon, Cinnamon A; Kelton, W David; Lindsell, Christopher J; Ward, Michael J

2014-08-01

Crowding and limited resources have increased the strain on acute care facilities and emergency departments worldwide. These problems are particularly prevalent in developing countries. Discrete event simulation is a computer-based tool that can be used to estimate how changes to complex health care delivery systems such as emergency departments will affect operational performance. Using this modality, our objective was to identify operational interventions that could potentially improve patient throughput of one acute care setting in a developing country. We developed a simulation model of acute care at a district level hospital in Ghana to test the effects of resource-neutral (eg, modified staff start times and roles) and resource-additional (eg, increased staff) operational interventions on patient throughput. Previously captured deidentified time-and-motion data from 487 acute care patients were used to develop and test the model. The primary outcome was the modeled effect of interventions on patient length of stay (LOS). The base-case (no change) scenario had a mean LOS of 292 minutes (95% confidence interval [CI], 291-293). In isolation, adding staffing, changing staff roles, and varying shift times did not affect overall patient LOS. Specifically, adding 2 registration workers, history takers, and physicians resulted in a 23.8-minute (95% CI, 22.3-25.3) LOS decrease. However, when shift start times were coordinated with patient arrival patterns, potential mean LOS was decreased by 96 minutes (95% CI, 94-98), and with the simultaneous combination of staff roles (registration and history taking), there was an overall mean LOS reduction of 152 minutes (95% CI, 150-154). Resource-neutral interventions identified through discrete event simulation modeling have the potential to improve acute care throughput in this Ghanaian municipal hospital. Discrete event simulation offers another approach to identifying potentially effective interventions to improve patient flow in emergency and acute care in resource-limited settings. Copyright © 2014 Elsevier Inc. All rights reserved.

Helicopter Evacuation Following a Rural Trauma: An Emergency Medicine Simulation Scenario Using Innovative Simulation Technology

PubMed Central

Whalen, Desmond; Harty, Chris; Ravalia, Mohamed; Renouf, Tia; Alani, Sabrina; Brown, Robert

2016-01-01

The relevance of simulation as a teaching tool for medical professionals working in rural and remote contexts is apparent when low-frequency, high-risk situations are considered. Simulation training has been shown to enhance learning and improve patient outcomes in urban settings. However, there are few simulation scenarios designed to teach rural trauma management during complex medical transportation. In this technical report, we present a scenario using a medevac helicopter (Replica of Sikorsky S-92 designed by Virtual Marine Technology, St. John's, NL) at a rural community. This case can be used for training primary care physicians who are working in a rural or remote setting, or as an innovative addition to emergency medicine and pre-hospital care training programs. PMID:27081585

ARCHER{sub RT} – A GPU-based and photon-electron coupled Monte Carlo dose computing engine for radiation therapy: Software development and application to helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Lin; Du, Xining; Liu, Tianyu

Purpose: Using the graphical processing units (GPU) hardware technology, an extremely fast Monte Carlo (MC) code ARCHER{sub RT} is developed for radiation dose calculations in radiation therapy. This paper describes the detailed software development and testing for three clinical TomoTherapy® cases: the prostate, lung, and head and neck. Methods: To obtain clinically relevant dose distributions, phase space files (PSFs) created from optimized radiation therapy treatment plan fluence maps were used as the input to ARCHER{sub RT}. Patient-specific phantoms were constructed from patient CT images. Batch simulations were employed to facilitate the time-consuming task of loading large PSFs, and to improvemore » the estimation of statistical uncertainty. Furthermore, two different Woodcock tracking algorithms were implemented and their relative performance was compared. The dose curves of an Elekta accelerator PSF incident on a homogeneous water phantom were benchmarked against DOSXYZnrc. For each of the treatment cases, dose volume histograms and isodose maps were produced from ARCHER{sub RT} and the general-purpose code, GEANT4. The gamma index analysis was performed to evaluate the similarity of voxel doses obtained from these two codes. The hardware accelerators used in this study are one NVIDIA K20 GPU, one NVIDIA K40 GPU, and six NVIDIA M2090 GPUs. In addition, to make a fairer comparison of the CPU and GPU performance, a multithreaded CPU code was developed using OpenMP and tested on an Intel E5-2620 CPU. Results: For the water phantom, the depth dose curve and dose profiles from ARCHER{sub RT} agree well with DOSXYZnrc. For clinical cases, results from ARCHER{sub RT} are compared with those from GEANT4 and good agreement is observed. Gamma index test is performed for voxels whose dose is greater than 10% of maximum dose. For 2%/2mm criteria, the passing rates for the prostate, lung case, and head and neck cases are 99.7%, 98.5%, and 97.2%, respectively. Due to specific architecture of GPU, modified Woodcock tracking algorithm performed inferior to the original one. ARCHER{sub RT} achieves a fast speed for PSF-based dose calculations. With a single M2090 card, the simulations cost about 60, 50, 80 s for three cases, respectively, with the 1% statistical error in the PTV. Using the latest K40 card, the simulations are 1.7–1.8 times faster. More impressively, six M2090 cards could finish the simulations in 8.9–13.4 s. For comparison, the same simulations on Intel E5-2620 (12 hyperthreading) cost about 500–800 s. Conclusions: ARCHER{sub RT} was developed successfully to perform fast and accurate MC dose calculation for radiotherapy using PSFs and patient CT phantoms.« less

Assessment of score- and Rasch-based methods for group comparison of longitudinal patient-reported outcomes with intermittent missing data (informative and non-informative).

PubMed

de Bock, Élodie; Hardouin, Jean-Benoit; Blanchin, Myriam; Le Neel, Tanguy; Kubis, Gildas; Sébille, Véronique

2015-01-01

The purpose of this study was to identify the most adequate strategy for group comparison of longitudinal patient-reported outcomes in the presence of possibly informative intermittent missing data. Models coming from classical test theory (CTT) and item response theory (IRT) were compared. Two groups of patients' responses to dichotomous items with three times of assessment were simulated. Different cases were considered: presence or absence of a group effect and/or a time effect, a total of 100 or 200 patients, 4 or 7 items and two different values for the correlation coefficient of the latent trait between two consecutive times (0.4 or 0.9). Cases including informative and non-informative intermittent missing data were compared at different rates (15, 30 %). These simulated data were analyzed with CTT using score and mixed model (SM) and with IRT using longitudinal Rasch mixed model (LRM). The type I error, the power and the bias of the group effect estimations were compared between the two methods. This study showed that LRM performs better than SM. When the rate of missing data rose to 30 %, estimations were biased with SM mainly for informative missing data. Otherwise, LRM and SM methods were comparable concerning biases. However, regardless of the rate of intermittent missing data, power of LRM was higher compared to power of SM. In conclusion, LRM should be favored when the rate of missing data is higher than 15 %. For other cases, SM and LRM provide similar results.

Melorheostosis of the ulna.

PubMed

Abdullah, Shalimar; Pang, Gerry M H; Mohamed-Haflah, Nor Hazla; Sapuan, Jamari

2011-10-01

Melorheostosis is a rare osteosclerotic bone dysplasia. It is usually characterized by dull and aching pain, reduced joint motion and contractures. Classic radiograph findings are of undulating cortical hyperostosis along the length of the bone, simulating a "dripping candlewax appearance". We report two cases of melorheostosis of the ulna bone, diagnosed 6 years apart in two different females in their early 20s. Both the patients presented with the characteristic features of dull and aching pain in the forearm and were treated conservatively. However, we misdiagnosed the first case as bone malignancy and subjected the patient to a biopsy. For the second case, with hindsight we made the correct diagnosis based only on the classic clinical history and radiographs. We believe that the discussion of a misdiagnosed case of melorheostosis with salient findings may be important for clinicians and orthopedicians in day-to-day clinical practice. Copyright © 2011. Published by Elsevier B.V.

Educational potential of a virtual patient system for caring for traumatized patients in primary care

PubMed Central

2013-01-01

Background Virtual Patients (VPs) have been used in undergraduate healthcare education for many years. This project is focused on using VPs for training professionals to care for highly vulnerable patient populations. The aim of the study was to evaluate if Refugee Trauma VPs was perceived as an effective and engaging learning tool by primary care professionals (PCPs) in a Primary Health Care Centre (PHC). Methods A VP system was designed to create realistic and engaging VP cases for Refugee Trauma for training refugee patient interview, use of established trauma and mental health instruments as well as to give feedback to the learners. The patient interview section was based on video clips with a Bosnian actor with a trauma story and mental health problems. The video clips were recorded in Bosnian language to further increase the realism, but also subtitled in English. The system was evaluated by 11 volunteering primary health clinicians at the Lynn Community Health Centre, Lynn, Massachusetts, USA. The participants were invited to provide insights/feedback about the system’s usefulness and educational value. A mixed methodological approach was used, generating both quantitative and qualitative data. Results Self-reported dimensions of clinical care, pre and post questionnaire questions on the PCPs clinical worldview, motivation to use the VP, and IT Proficiency. Construct items used in these questionnaires had previously demonstrated high face and construct validity. The participants ranked the mental status examination more positively after the simulation exercise compared to before the simulation. Follow up interviews supported the results. Conclusions Even though virtual clinical encounters are quite a new paradigm in PHC, the participants in the present study considered our VP case to be a relevant and promising educational tool. Next phase of our project will be a RCT study including comparison with specially prepared paper-cases and determinative input on improving clinical diagnosis and treatment of the traumatized refugee patient. PMID:23957962

Fast Numerical Simulation of Focused Ultrasound Treatments During Respiratory Motion With Discontinuous Motion Boundaries.

PubMed

Schwenke, Michael; Georgii, Joachim; Preusser, Tobias

2017-07-01

Focused ultrasound (FUS) is rapidly gaining clinical acceptance for several target tissues in the human body. Yet, treating liver targets is not clinically applied due to a high complexity of the procedure (noninvasiveness, target motion, complex anatomy, blood cooling effects, shielding by ribs, and limited image-based monitoring). To reduce the complexity, numerical FUS simulations can be utilized for both treatment planning and execution. These use-cases demand highly accurate and computationally efficient simulations. We propose a numerical method for the simulation of abdominal FUS treatments during respiratory motion of the organs and target. Especially, a novel approach is proposed to simulate the heating during motion by solving Pennes' bioheat equation in a computational reference space, i.e., the equation is mathematically transformed to the reference. The approach allows for motion discontinuities, e.g., the sliding of the liver along the abdominal wall. Implementing the solver completely on the graphics processing unit and combining it with an atlas-based ultrasound simulation approach yields a simulation performance faster than real time (less than 50-s computing time for 100 s of treatment time) on a modern off-the-shelf laptop. The simulation method is incorporated into a treatment planning demonstration application that allows to simulate real patient cases including respiratory motion. The high performance of the presented simulation method opens the door to clinical applications. The methods bear the potential to enable the application of FUS for moving organs.

[Risk assessment of rescue helicopter or ambulance transport of patients ingesting hazardous volatile materials].

PubMed

Takegawa, Ryosuke; Ohnishi, Mitsuo; Hirose, Tomoya; Hatano, Yayoi; Imada, Yuko; Endo, Yoko; Shimazu, Takeshi

2016-03-01

In cases of transport by rescue helicopter or ambulance of patients having ingested hazardous substances, medical personnel may be at a certain risk of inhaling the substances. However, few reports have addressed such risk of causing secondary casualties. This simulation study aimed to assess the risk of inhalation of hydrogen sulfide and chlo-opicrin in the cabin of a helicopter or an ambulance transporting a patient who has ingested calcium polysulfide or chloropicrin, which were previously reported to cause secondary casualties. Concentrations of hydrogen sulfide and chloropicrin were assessed on the following as-umptions :The patient ingested 100 mL of the causative or original chemical. All chemical substances reacted with the gastric juice or were thoroughly vomited and evaporated uniformly within the cabin space of the helicopter or ambulance. Environmental conditions were 20 *degrees at 1 atmosphere of pres-ure in a 5 m3 cabin volume in the helicopter and a 13.5 m3 cabin volume in the ambulance. In the case of calcium polysulfide ingestion which produced hydrogen sulfide, its concen-ration reached 774 ppm in the helicopter and 287 ppm in the ambulance. For chloropicrin ingestion, the concentrations were 4,824 ppm and 1,787 ppm, respectively. The simulated concentration of hydrogen sulfide was more than 500 ppm in the heli-opter, which may lead to respiratory paralysis and death. The simulated concentration of chloropicrin was more than 300 ppm, which has a risk of death within 10 minutes. Currently, as far as Japanese laws are concerned, there are no restrictions requiring pretransport assessment or setting criteria for transporting patients who might have ingested hazardous substances that could cause secondary casu-lties when vomited. When patients who might have ingested hazardous chemicals are transported, it is important to recognize the risk of causing secondary casualties by vomiting the chemicals.

Cuboid oedema due to peroneus longus tendinopathy: a report of four cases.

PubMed

O'Donnell, Paul; Saifuddin, Asif

2005-07-01

To highlight focal bone abnormality in the cuboid due to tendinopathy of the adjacent peroneus longus. A retrospective review was carried out of the relevant clinical and imaging features. Two male and two female patients were studied, mean age 51.5 years (range 32-67 years), referred with foot pain and imaging showing an abnormal cuboid thought to represent either tumour or infection. A long history of foot pain was usual with a maximum of 8 years. Radiographs were normal in two cases and showed erosion in two, one of which exhibited periosteal new bone formation affecting the cuboid. Bone scintigraphy was undertaken in two patients, both of whom showed increased uptake of isotope. MRI, performed in all patients, showed oedema in the cuboid adjacent to the peroneus longus tendon. The tendon and/or paratendinous tissues were abnormal in all cases, but no tendon discontinuity was identified. One patient possessed an os peroneum. Unequivocal evidence of bone erosion was seen using MRI in three patients, but with greater clarity in two cases using CT. Additional findings of tenosynovitis of tibialis posterior, oedema in the adjacent medial malleolus and synovitis of multiple joints in the foot were seen in one patient. Imaging diagnosis was made in all cases avoiding bone biopsy, but surgical exploration of the peroneal tendons was performed in two cases and biopsy of ankle synovium in one. Oedema with erosion of the cuboid bone, simulating a bone lesion (cuboid "pseudotumour"), may be caused by adjacent tendinopathy of peroneus longus. It is vital to be aware of this entity to avoid unnecessary biopsy of the cuboid.

Assessing the robustness of passive scattering proton therapy with regard to local recurrence in stage III non-small cell lung cancer: a secondary analysis of a phase II trial.

PubMed

Zhu, Zhengfei; Liu, Wei; Gillin, Michael; Gomez, Daniel R; Komaki, Ritsuko; Cox, James D; Mohan, Radhe; Chang, Joe Y

2014-05-06

We assessed the robustness of passive scattering proton therapy (PSPT) plans for patients in a phase II trial of PSPT for stage III non-small cell lung cancer (NSCLC) by using the worst-case scenario method, and compared the worst-case dose distributions with the appearance of locally recurrent lesions. Worst-case dose distributions were generated for each of 9 patients who experienced recurrence after concurrent chemotherapy and PSPT to 74 Gy(RBE) for stage III NSCLC by simulating and incorporating uncertainties associated with set-up, respiration-induced organ motion, and proton range in the planning process. The worst-case CT scans were then fused with the positron emission tomography (PET) scans to locate the recurrence. Although the volumes enclosed by the prescription isodose lines in the worst-case dose distributions were consistently smaller than enclosed volumes in the nominal plans, the target dose coverage was not significantly affected: only one patient had a recurrence outside the prescription isodose lines in the worst-case plan. PSPT is a relatively robust technique. Local recurrence was not associated with target underdosage resulting from estimated uncertainties in 8 of 9 cases.

Robustness Recipes for Minimax Robust Optimization in Intensity Modulated Proton Therapy for Oropharyngeal Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voort, Sebastian van der; Section of Nuclear Energy and Radiation Applications, Department of Radiation, Science and Technology, Delft University of Technology, Delft; Water, Steven van de

Purpose: We aimed to derive a “robustness recipe” giving the range robustness (RR) and setup robustness (SR) settings (ie, the error values) that ensure adequate clinical target volume (CTV) coverage in oropharyngeal cancer patients for given gaussian distributions of systematic setup, random setup, and range errors (characterized by standard deviations of Σ, σ, and ρ, respectively) when used in minimax worst-case robust intensity modulated proton therapy (IMPT) optimization. Methods and Materials: For the analysis, contoured computed tomography (CT) scans of 9 unilateral and 9 bilateral patients were used. An IMPT plan was considered robust if, for at least 98% of themore » simulated fractionated treatments, 98% of the CTV received 95% or more of the prescribed dose. For fast assessment of the CTV coverage for given error distributions (ie, different values of Σ, σ, and ρ), polynomial chaos methods were used. Separate recipes were derived for the unilateral and bilateral cases using one patient from each group, and all 18 patients were included in the validation of the recipes. Results: Treatment plans for bilateral cases are intrinsically more robust than those for unilateral cases. The required RR only depends on the ρ, and SR can be fitted by second-order polynomials in Σ and σ. The formulas for the derived robustness recipes are as follows: Unilateral patients need SR = −0.15Σ{sup 2} + 0.27σ{sup 2} + 1.85Σ − 0.06σ + 1.22 and RR=3% for ρ = 1% and ρ = 2%; bilateral patients need SR = −0.07Σ{sup 2} + 0.19σ{sup 2} + 1.34Σ − 0.07σ + 1.17 and RR=3% and 4% for ρ = 1% and 2%, respectively. For the recipe validation, 2 plans were generated for each of the 18 patients corresponding to Σ = σ = 1.5 mm and ρ = 0% and 2%. Thirty-four plans had adequate CTV coverage in 98% or more of the simulated fractionated treatments; the remaining 2 had adequate coverage in 97.8% and 97.9%. Conclusions: Robustness recipes were derived that can be used in minimax robust optimization of IMPT treatment plans to ensure adequate CTV coverage for oropharyngeal cancer patients.« less

An Assessment of an Oral Examination Format for Evaluating Clinical Competence in Emergency Medicine.

ERIC Educational Resources Information Center

Solomon, David J.; And Others

1990-01-01

In July 1989 the American Board of Emergency Medicine conducted a field test of the oral recertification examination process. Sixteen examiners and 25 examinees participated in the field test. The examination included 3 chart-stimulated recall and 3 simulated-patient encounter cases. (MLW)

Quality assurance study of caries risk assessment performance by clinical faculty members in a school of dentistry.

PubMed

Rechmann, Peter; Featherstone, John D B

2014-09-01

The goal of this quality assurance study was to explore the decision making of clinical faculty members at the University of California, San Francisco School of Dentistry predoctoral dental clinic in terms of caries risk level assignment using the caries risk assessment (CRA) as part of the Caries Management by Risk Assessment (CAMBRA) concept. This research was done in part to determine if additional training and calibration were needed for these faculty members. The study tested the reliability and reproducibility of the caries risk levels assigned by different clinical teachers who completed CRA forms for simulated patients. In the first step, five clinical teachers assigned caries risk levels for thirteen simulated patients. Six months later, the same five plus an additional nine faculty members assigned caries risk levels to the same thirteen simulated and nine additional cases. While the intra-examiner reliability with weighted kappa strength of agreement was very high, the inter-examiner agreements with a gold standard were on average only moderate. In total, 20 percent of the presented high caries risk cases were underestimated at caries levels too low, even when obvious caries disease indicators were present. This study suggests that more consistent training and calibration of clinical faculty members as well as students are needed.

Religious stigmata as malingering artifact

PubMed Central

Bonamonte, Domenico; Vestita, Michelangelo; Filoni, Angela; Giudice, Giuseppe; Angelini, Gianni

2016-01-01

Abstract Rationale: Artifacts or simulated diseases are self-inflicted conditions caused by various means and for different purposes. Disease simulation can be motivated, among other things, by illegal purposes, to escape from civil duties or prison sentences, for example, or to exploit specific situations in order to receive a range of benefits. In such cases, the simulator is fully aware of his or her actions and intentions. Diagnoses, Interventions and Outcomes: We report the case of a 42-year-old woman who, for 3 consecutive years, showed religious stigmata on the forehead and on the dorsal surface of hands and feet immediately before Easter. Lesions showed an acute onset, manifested as erosions and ulcerations, and healed a few days after Easter. Stigmata were immediately made public and every year faithful and curious people went in procession to the house of the patient, offering different kinds of gifts. After intervention of the police authority in the early days of the third episode, the patient and her family repented of their actions. Cutaneous lesions healed in few days and similar events did not occur during the following 2 years. Lessons: Regardless of personal beliefs, the possibility that stigmata could be self-inflicted for illegal or profit purposes should always be considered. PMID:27930512

A randomized trial of teaching clinical skills using virtual and live standardized patients.

PubMed

Triola, M; Feldman, H; Kalet, A L; Zabar, S; Kachur, E K; Gillespie, C; Anderson, M; Griesser, C; Lipkin, M

2006-05-01

We developed computer-based virtual patient (VP) cases to complement an interactive continuing medical education (CME) course that emphasizes skills practice using standardized patients (SP). Virtual patient simulations have the significant advantages of requiring fewer personnel and resources, being accessible at any time, and being highly standardized. Little is known about the educational effectiveness of these new resources. We conducted a randomized trial to assess the educational effectiveness of VPs and SPs in teaching clinical skills. To determine the effectiveness of VP cases when compared with live SP cases in improving clinical skills and knowledge. Randomized trial. Fifty-five health care providers (registered nurses 45%, physicians 15%, other provider types 40%) who attended a CME program. Participants were randomized to receive either 4 live cases (n=32) or 2 live and 2 virtual cases (n=23). Other aspects of the course were identical for both groups. Participants in both groups were equivalent with respect to pre-post workshop improvement in comfort level (P=.66) and preparedness to respond (P=.61), to screen (P=.79), and to care (P=.055) for patients using the skills taught. There was no difference in subjective ratings of effectiveness of the VPs and SPs by participants who experienced both (P=.79). Improvement in diagnostic abilities were equivalent in groups who experienced cases either live or virtually. Improvements in performance and diagnostic ability were equivalent between the groups and participants rated VP and SP cases equally. Including well-designed VPs has a potentially powerful and efficient place in clinical skills training for practicing health care workers.

Hepatitis C virus infection can mimic type 1 (antinuclear antibody positive) autoimmune chronic active hepatitis.

PubMed Central

Pawlotsky, J M; Deforges, L; Bretagne, S; André, C; Métreau, J M; Thiers, V; Zafrani, E S; Goossens, M; Duval, J; Mavier, J P

1993-01-01

Hepatitis C virus (HCV) has been shown to induce anti-liver-kidney microsomal-1 (LKM1) antibody positive chronic active hepatitis, simulating type 2 autoimmune chronic active hepatitis. The cases of five patients presenting with features of type 1 (antinuclear antibody positive) autoimmune chronic active hepatitis and extrahepatic autoimmune manifestations, in whom immunosuppressive treatment had no effect on liver disease are presented. In these patients, HCV infection could be shown by the presence in serum of anti-HCV antibodies and HCV-RNA detected by polymerase chain reaction. These cases suggest the following: (a) chronic HCV infection can mimic type 1, as well as type 2, autoimmune chronic active hepatitis; (b) HCV infection might be systematically sought in patients presenting with features of type 1 autoimmune chronic active hepatitis, with special care in patients who are unresponsive to immunosuppressive treatment. Images Figure PMID:7686122

Brachial Plexus Injury from CT-Guided RF Ablation Under General Anesthesia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shankar, Sridhar, E-mail: shankars@ummhc.org; Sonnenberg, Eric van; Silverman, Stuart G.

2005-06-15

Brachial plexus injury in a patient under general anesthesia (GA) is not uncommon, despite careful positioning and, particularly, awareness of the possibility. The mechanism of injury is stretching and compression of the brachial plexus over a prolonged period. Positioning the patient within the computed tomography (CT) gantry for abdominal or chest procedures can simulate a surgical procedure, particularly when GA is used. The potential for brachial plexus injury is increased if the case is prolonged and the patient's arms are raised above the head to avoid CT image degradation from streak artifacts. We report a case of profound brachial plexusmore » palsy following a CT-guided radiofrequency ablation procedure under GA. Fortunately, the patient recovered completely. We emphasize the mechanism of injury and detail measures to combat this problem, such that radiologists are aware of this potentially serious complication.« less

Hemodynamic simulations in coronary aneurysms of children with Kawasaki disease

NASA Astrophysics Data System (ADS)

Sengupta, Dibyendu; Burns, Jane; Marsden, Alison

2009-11-01

Kawasaki disease (KD) is a serious pediatric illness affecting the cardiovascular system. One of the most serious complications of KD, occurring in about 25% of untreated cases, is the formation of large aneurysms in the coronary arteries, which put patients at risk for myocardial infarction. In this project we performed patient specific computational simulations of blood flow in aneurysmal left and right coronary arteries of a KD patient to gain an understanding about their hemodynamics. Models were constructed from CT data using custom software. Typical pulsatile flow waveforms were applied at the model inlets, while resistance and RCR lumped models were applied and compared at the outlets. Simulated pressure waveforms compared well with typical physiologic data. High wall shear stress values are found in the narrow region at the base of the aneurysm and low shear values occur in regions of recirculation. A Lagrangian approach has been adopted to perform particle tracking and compute particle residence time in the recirculation. Our long-term goal will be to develop links between hemodynamics and the risk for thrombus formation in order to assist in clinical decision-making.

Performance characteristics of a conformal ultra-wideband multilayer applicator (CUMLA) for hyperthermia in veterinary patients: a pilot evaluation of its use in the adjuvant treatment of non-resectable tumours.

PubMed

Smrkovski, O A; Koo, Y; Kazemi, R; Lembcke, L M; Fathy, A; Liu, Q; Phillips, J C

2013-03-01

Performance and clinical characteristics of a novel hyperthermia antenna operating at 434 MHz were evaluated for the adjuvant treatment of locally advanced superficial tumours in cats, dogs and horses. Electromagnetic simulations were performed to determine electric field characteristics and compared to simulations for a flat microwave antenna with similar dimensions. Simulation results show a reduced skin surface and backfield irradiation and improved directional irradiation (at broadside) compared to a flat antenna. Radiated power and penetration is notably increased with a penetration depth of 4.59 cm compared to 2.74 cm for the flat antenna. Clinical use of the antenna was then evaluated in six animals with locoregionally advanced solid tumours receiving adjuvant chemotherapy. During clinical applications, therapeutic temperatures were achieved at depths ≥4 cm. Objective responses were seen in all patients; tissue toxicity in one case limited further therapy. This antenna provides compact, efficient, focused and deep-penetrating clinical hyperthermia for the treatment of solid tumours in veterinary patients. © 2011 Blackwell Publishing Ltd.

Interdisciplinary pharmacometrics linking oseltamivir pharmacology, influenza epidemiology and health economics to inform antiviral use in pandemics.

PubMed

Kamal, Mohamed A; Smith, Patrick F; Chaiyakunapruk, Nathorn; Wu, David B C; Pratoomsoot, Chayanin; Lee, Kenneth K C; Chong, Huey Yi; Nelson, Richard E; Nieforth, Keith; Dall, Georgina; Toovey, Stephen; Kong, David C M; Kamauu, Aaron; Kirkpatrick, Carl M; Rayner, Craig R

2017-07-01

A modular interdisciplinary platform was developed to investigate the economic impact of oseltamivir treatment by dosage regimen under simulated influenza pandemic scenarios. The pharmacology module consisted of a pharmacokinetic distribution of oseltamivir carboxylate daily area under the concentration-time curve at steady state (simulated for 75 mg and 150 mg twice daily regimens for 5 days) and a pharmacodynamic distribution of viral shedding duration obtained from phase II influenza inoculation data. The epidemiological module comprised a susceptible, exposed, infected, recovered (SEIR) model to which drug effect on the basic reproductive number (R 0 ), a measure of transmissibility, was linked by reduction of viral shedding duration. The number of infected patients per population of 100 000 susceptible individuals was simulated for a series of pandemic scenarios, varying oseltamivir dose, R 0 (1.9 vs. 2.7), and drug uptake (25%, 50%, and 80%). The number of infected patients for each scenario was entered into the health economics module, a decision analytic model populated with branch probabilities, disease utility, costs of hospitalized patients developing complications, and case-fatality rates. Change in quality-adjusted life years was determined relative to base case. Oseltamivir 75 mg relative to no treatment reduced the median number of infected patients, increased change in quality-adjusted life years by deaths averted, and was cost-saving under all scenarios; 150 mg relative to 75 mg was not cost effective in low transmissibility scenarios but was cost saving in high transmissibility scenarios. This methodological study demonstrates proof of concept that the disciplines of pharmacology, disease epidemiology and health economics can be linked in a single quantitative framework. © 2017 The British Pharmacological Society.

Performance factors of mobile rich media job aids for community health workers

PubMed Central

Florez-Arango, Jose F; Dunn, Kim; Zhang, Jiajie

2011-01-01

Objective To study and analyze the possible benefits on performance of community health workers using point-of-care clinical guidelines implemented as interactive rich media job aids on small-format mobile platforms. Design A crossover study with one intervention (rich media job aids) and one control (traditional job aids), two periods, with 50 community health workers, each subject solving a total 15 standardized cases per period per period (30 cases in total per subject). Measurements Error rate per case and task, protocol compliance. Results A total of 1394 cases were evaluated. Intervention reduces errors by an average of 33.15% (p=0.001) and increases protocol compliance 30.18% (p<0.001). Limitations Medical cases were presented on human patient simulators in a laboratory setting, not on real patients. Conclusion These results indicate encouraging prospects for mHealth technologies in general, and the use of rich media clinical guidelines on cell phones in particular, for the improvement of community health worker performance in developing countries. PMID:21292702

Performance factors of mobile rich media job aids for community health workers.

PubMed

Florez-Arango, Jose F; Iyengar, M Sriram; Dunn, Kim; Zhang, Jiajie

2011-01-01

To study and analyze the possible benefits on performance of community health workers using point-of-care clinical guidelines implemented as interactive rich media job aids on small-format mobile platforms. A crossover study with one intervention (rich media job aids) and one control (traditional job aids), two periods, with 50 community health workers, each subject solving a total 15 standardized cases per period per period (30 cases in total per subject). Error rate per case and task, protocol compliance. A total of 1394 cases were evaluated. Intervention reduces errors by an average of 33.15% (p = 0.001) and increases protocol compliance 30.18% (p < 0.001). Limitations Medical cases were presented on human patient simulators in a laboratory setting, not on real patients. These results indicate encouraging prospects for mHealth technologies in general, and the use of rich media clinical guidelines on cell phones in particular, for the improvement of community health worker performance in developing countries.

Attenuation-emission alignment in cardiac PET∕CT based on consistency conditions

PubMed Central

Alessio, Adam M.; Kinahan, Paul E.; Champley, Kyle M.; Caldwell, James H.

2010-01-01

Purpose: In cardiac PET and PET∕CT imaging, misaligned transmission and emission images are a common problem due to respiratory and cardiac motion. This misalignment leads to erroneous attenuation correction and can cause errors in perfusion mapping and quantification. This study develops and tests a method for automated alignment of attenuation and emission data. Methods: The CT-based attenuation map is iteratively transformed until the attenuation corrected emission data minimize an objective function based on the Radon consistency conditions. The alignment process is derived from previous work by Welch et al. [“Attenuation correction in PET using consistency information,” IEEE Trans. Nucl. Sci. 45, 3134–3141 (1998)] for stand-alone PET imaging. The process was evaluated with the simulated data and measured patient data from multiple cardiac ammonia PET∕CT exams. The alignment procedure was applied to simulations of five different noise levels with three different initial attenuation maps. For the measured patient data, the alignment procedure was applied to eight attenuation-emission combinations with initially acceptable alignment and eight combinations with unacceptable alignment. The initially acceptable alignment studies were forced out of alignment a known amount and quantitatively evaluated for alignment and perfusion accuracy. The initially unacceptable studies were compared to the proposed aligned images in a blinded side-by-side review. Results: The proposed automatic alignment procedure reduced errors in the simulated data and iteratively approaches global minimum solutions with the patient data. In simulations, the alignment procedure reduced the root mean square error to less than 5 mm and reduces the axial translation error to less than 1 mm. In patient studies, the procedure reduced the translation error by >50% and resolved perfusion artifacts after a known misalignment for the eight initially acceptable patient combinations. The side-by-side review of the proposed aligned attenuation-emission maps and initially misaligned attenuation-emission maps revealed that reviewers preferred the proposed aligned maps in all cases, except one inconclusive case. Conclusions: The proposed alignment procedure offers an automatic method to reduce attenuation correction artifacts in cardiac PET∕CT and provides a viable supplement to subjective manual realignment tools. PMID:20384256

Trialability, observability and risk reduction accelerating individual innovation adoption decisions.

PubMed

Hayes, Kathryn J; Eljiz, Kathy; Dadich, Ann; Fitzgerald, Janna-Anneke; Sloan, Terry

2015-01-01

The purpose of this paper is to provide a retrospective analysis of computer simulation's role in accelerating individual innovation adoption decisions. The process innovation examined is Lean Systems Thinking, and the organizational context is the imaging department of an Australian public hospital. Intrinsic case study methods including observation, interviews with radiology and emergency personnel about scheduling procedures, mapping patient appointment processes and document analysis were used over three years and then complemented with retrospective interviews with key hospital staff. The multiple data sources and methods were combined in a pragmatic and reflexive manner to explore an extreme case that provides potential to act as an instructive template for effective change. Computer simulation of process change ideas offered by staff to improve patient-flow accelerated the adoption of the process changes, largely because animated computer simulation permitted experimentation (trialability), provided observable predictions of change results (observability) and minimized perceived risk. The difficulty of making accurate comparisons between time periods in a health care setting is acknowledged. This work has implications for policy, practice and theory, particularly for inducing the rapid diffusion of process innovations to address challenges facing health service organizations and national health systems. Originality/value - The research demonstrates the value of animated computer simulation in presenting the need for change, identifying options, and predicting change outcomes and is the first work to indicate the importance of trialability, observability and risk reduction in individual adoption decisions in health services.

Junior physician skill and behaviour in resuscitation: a simulation study.

PubMed

Høyer, Christian Bjerre; Christensen, Erika F; Eika, Berit

2009-02-01

Physicians are expected to manage their role as teamleader during resuscitation. During inter-hospital transfer the physician has the highest medical credentials on a small team. The aim of this study was to describe physician behaviour as teamleaders in a simulated cardiac arrest during inter-hospital transfer. Our goal was to pinpoint deficits in knowledge and skill integration and make recommendations for improvements in education. An ambulance was the framework for the simulation; the scenario a patient with acute coronary syndrome suffering ventricular fibrillation during transportation. Physicians (graduation age < or =5 years) working in internal medicine departments in Denmark were studied. The ambulance crew was instructed to be passive to clarify the behaviour of the physicians. 72 physicians were studied. Chest compressions were initiated in 71 cases, ventilation and defibrillation in 72. The median times for arrival of the driver in the patient cabin, initiation of ventilation and chest compressions, and first defibrillation were all less than 1min. Medication was administered in 63/72 simulations (88%), after a median time of 210 s. Adrenaline was the preferred initial drug administered (58/63, 92%). Tasks delegated were ventilations, chest compressions, defibrillation, and administration of medication (97%, 92%, 42%, and 10% of cases, respectively). Junior physicians performed well with respect to the treatment given and the delegation of tasks. However, variations in the time of initiation it took for each treatment indicated lack of leadership skills. It is imperative that the education of physicians includes training in leadership.

[Simulation training in the management of obstetric emergencies. A review of the literature].

PubMed

Bogne, V; Kirkpatrick, C; Englert, Y

2014-01-01

To assess the value of simulation based training in the management of obstetric emergencies. A search by keywords: obstetrics, gynecology, simulation, drills, emergency training restricted to randomized trials led to a selection of eight articles. Shoulder dystocia simulation unmasked deficiencies in performing Mc Robert maneuver in nearly 20% of doctors in training as well as ineffective and potentially harmful maneuver such as pressure on the uterine fundus. Delivery of the impacted shoulder improved from 42.9% to 83.3% after simulation training leading to a shorter head to body delivery interval. In postpartum haemorrhage simulation, lack of knowledge on prostaglandins and alkaloids of ergot, delay to transfer the patient to the operating room (82% of cases) and a poor communication between different professionals were identified. Post simulation improvement was seen in knowledge, technical skills, team spirit and structured communication. In severe preeclampsia simulation, mistakes such as injection of undiluted magnesium sulphate, caesarean section on an unstable patient were identified and reduced by 75%. Management of magnesium sulphate toxicity was also improved after simulation training. This review confirms the potential of simulation in training health professionals on management of obstetrics emergencies. Although the integration of this training modality into the curriculum of health care professionals in obstetrics and gynaecology seems beneficial, questions on the cost, the minimum standard of facilities, type of mannequins, human resources and frequency of drills required to achieve the learning objectives remain unanswered.

Optical design of a novel instrument that uses the Hartmann-Shack sensor and Zernike polynomials to measure and simulate customized refraction correction surgery outcomes and patient satisfaction

NASA Astrophysics Data System (ADS)

Yasuoka, Fatima M. M.; Matos, Luciana; Cremasco, Antonio; Numajiri, Mirian; Marcato, Rafael; Oliveira, Otavio G.; Sabino, Luis G.; Castro N., Jarbas C.; Bagnato, Vanderlei S.; Carvalho, Luis A. V.

2016-03-01

An optical system that conjugates the patient's pupil to the plane of a Hartmann-Shack (HS) wavefront sensor has been simulated using optical design software. And an optical bench prototype is mounted using mechanical eye device, beam splitter, illumination system, lenses, mirrors, mirrored prism, movable mirror, wavefront sensor and camera CCD. The mechanical eye device is used to simulate aberrations of the eye. From this device the rays are emitted and travelled by the beam splitter to the optical system. Some rays fall on the camera CCD and others pass in the optical system and finally reach the sensor. The eye models based on typical in vivo eye aberrations is constructed using the optical design software Zemax. The computer-aided outcomes of each HS images for each case are acquired, and these images are processed using customized techniques. The simulated and real images for low order aberrations are compared using centroid coordinates to assure that the optical system is constructed precisely in order to match the simulated system. Afterwards a simulated version of retinal images is constructed to show how these typical eyes would perceive an optotype positioned 20 ft away. Certain personalized corrections are allowed by eye doctors based on different Zernike polynomial values and the optical images are rendered to the new parameters. Optical images of how that eye would see with or without corrections of certain aberrations are generated in order to allow which aberrations can be corrected and in which degree. The patient can then "personalize" the correction to their own satisfaction. This new approach to wavefront sensing is a promising change in paradigm towards the betterment of the patient-physician relationship.

Detailed prospective peer review in a community radiation oncology clinic.

PubMed

Mitchell, James D; Chesnut, Thomas J; Eastham, David V; Demandante, Carlo N; Hoopes, David J

In 2012, we instituted detailed prospective peer review of new cases. We present the outcomes of peer review on patient management and time required for peer review. Peer review rounds were held 3 to 4 days weekly and required 2 physicians to review pertinent information from the electronic medical record and treatment planning system. Eight aspects were reviewed for each case: 1) workup and staging; 2) treatment intent and prescription; 3) position, immobilization, and simulation; 4) motion assessment and management; 5) target contours; 6) normal tissue contours; 7) target dosimetry; and 8) normal tissue dosimetry. Cases were marked as, "Meets standard of care," "Variation," or "Major deviation." Changes in treatment plan were noted. As our process evolved, we recorded the time spent reviewing each case. From 2012 to 2014, we collected peer review data on 442 of 465 (95%) radiation therapy patients treated in our hospital-based clinic. Overall, 91 (20.6%) of the cases were marked as having a variation, and 3 (0.7%) as major deviation. Forty-two (9.5%) of the cases were altered after peer review. An overall peer review score of "Variation" or "Major deviation" was highly associated with a change in treatment plan (P < .01). Changes in target contours were recommended in 10% of cases. Gastrointestinal cases were significantly associated with a change in treatment plan after peer review. Indicators on position, immobilization, simulation, target contours, target dosimetry, motion management, normal tissue contours, and normal tissue dosimetry were significantly associated with a change in treatment plan. The mean time spent on each case was 7 minutes. Prospective peer review is feasible in a community radiation oncology practice. Our process led to changes in 9.5% of cases. Peer review should focus on technical factors such as target contours and dosimetry. Peer review required 7 minutes per case. Published by Elsevier Inc.

A Multi-Institutional Simulation Boot Camp for Pediatric Cardiac Critical Care Nurse Practitioners.

PubMed

Brown, Kristen M; Mudd, Shawna S; Hunt, Elizabeth A; Perretta, Julianne S; Shilkofski, Nicole A; Diddle, J Wesley; Yurasek, Gregory; Bembea, Melania; Duval-Arnould, Jordan; Nelson McMillan, Kristen

2018-06-01

Assess the effect of a simulation "boot camp" on the ability of pediatric nurse practitioners to identify and treat a low cardiac output state in postoperative patients with congenital heart disease. Additionally, assess the pediatric nurse practitioners' confidence and satisfaction with simulation training. Prospective pre/post interventional pilot study. University simulation center. Thirty acute care pediatric nurse practitioners from 13 academic medical centers in North America. We conducted an expert opinion survey to guide curriculum development. The curriculum included didactic sessions, case studies, and high-fidelity simulation, based on high-complexity cases, congenital heart disease benchmark procedures, and a mix of lesion-specific postoperative complications. To cover multiple, high-complexity cases, we implemented Rapid Cycle Deliberate Practice method of teaching for selected simulation scenarios using an expert driven checklist. Knowledge was assessed with a pre-/posttest format (maximum score, 100%). A paired-sample t test showed a statistically significant increase in the posttest scores (mean [SD], pre test, 36.8% [14.3%] vs post test, 56.0% [15.8%]; p < 0.001). Time to recognize and treat an acute deterioration was evaluated through the use of selected high-fidelity simulation. Median time improved overall "time to task" across these scenarios. There was a significant increase in the proportion of clinically time-sensitive tasks completed within 5 minutes (pre, 60% [30/50] vs post, 86% [43/50]; p = 0.003] Confidence and satisfaction were evaluated with a validated tool ("Student Satisfaction and Self-Confidence in Learning"). Using a five-point Likert scale, the participants reported a high level of satisfaction (4.7 ± 0.30) and performance confidence (4.8 ± 0.31) with the simulation experience. Although simulation boot camps have been used effectively for training physicians and educating critical care providers, this was a novel approach to educating pediatric nurse practitioners from multiple academic centers. The course improved overall knowledge, and the pediatric nurse practitioners reported satisfaction and confidence in the simulation experience.

Commercial flight and patients with intracranial mass lesions: a caveat. Report of two cases.

PubMed

Zrinzo, Ludvic U; Crocker, Matthew; Zrinzo, Laurence V; Thomas, David G T; Watkins, Laurence

2006-10-01

The authors report two cases of neurological deterioration following long commercial flights. Both individuals harbored intracranial space-occupying lesions. The authors assert that preexisting reduced intracranial compliance diminishes an individual's reserve to accommodate the physiological changes resulting from a commercial flight. Airline passengers are exposed to a mild degree of hypercapnia as well as conditions that simulate those of high-altitude ascents. High-altitude cerebral edema following an ascent to great heights is one facet of acute mountain sickness and can be life threatening in conditions similar to those present on commercial flights. Comparable reports documenting neurological deterioration at high altitudes in patients with coexisting space-occupying lesions were also reviewed.

Improving operating room productivity via parallel anesthesia processing.

PubMed

Brown, Michael J; Subramanian, Arun; Curry, Timothy B; Kor, Daryl J; Moran, Steven L; Rohleder, Thomas R

2014-01-01

Parallel processing of regional anesthesia may improve operating room (OR) efficiency in patients undergoes upper extremity surgical procedures. The purpose of this paper is to evaluate whether performing regional anesthesia outside the OR in parallel increases total cases per day, improve efficiency and productivity. Data from all adult patients who underwent regional anesthesia as their primary anesthetic for upper extremity surgery over a one-year period were used to develop a simulation model. The model evaluated pure operating modes of regional anesthesia performed within and outside the OR in a parallel manner. The scenarios were used to evaluate how many surgeries could be completed in a standard work day (555 minutes) and assuming a standard three cases per day, what was the predicted end-of-day time overtime. Modeling results show that parallel processing of regional anesthesia increases the average cases per day for all surgeons included in the study. The average increase was 0.42 surgeries per day. Where it was assumed that three cases per day would be performed by all surgeons, the days going to overtime was reduced by 43 percent with parallel block. The overtime with parallel anesthesia was also projected to be 40 minutes less per day per surgeon. Key limitations include the assumption that all cases used regional anesthesia in the comparisons. Many days may have both regional and general anesthesia. Also, as a case study, single-center research may limit generalizability. Perioperative care providers should consider parallel administration of regional anesthesia where there is a desire to increase daily upper extremity surgical case capacity. Where there are sufficient resources to do parallel anesthesia processing, efficiency and productivity can be significantly improved. Simulation modeling can be an effective tool to show practice change effects at a system-wide level.

Human swallowing simulation based on videofluorography images using Hamiltonian MPS method

NASA Astrophysics Data System (ADS)

Kikuchi, Takahiro; Michiwaki, Yukihiro; Kamiya, Tetsu; Toyama, Yoshio; Tamai, Tasuku; Koshizuka, Seiichi

2015-09-01

In developed nations, swallowing disorders and aspiration pneumonia have become serious problems. We developed a method to simulate the behavior of the organs involved in swallowing to clarify the mechanisms of swallowing and aspiration. The shape model is based on anatomically realistic geometry, and the motion model utilizes forced displacements based on realistic dynamic images to reflect the mechanisms of human swallowing. The soft tissue organs are modeled as nonlinear elastic material using the Hamiltonian MPS method. This method allows for stable simulation of the complex swallowing movement. A penalty method using metaballs is employed to simulate contact between organ walls and smooth sliding along the walls. We performed four numerical simulations under different analysis conditions to represent four cases of swallowing, including a healthy volunteer and a patient with a swallowing disorder. The simulation results were compared to examine the epiglottic downfolding mechanism, which strongly influences the risk of aspiration.

Large-Scale Brain Simulation and Disorders of Consciousness. Mapping Technical and Conceptual Issues.

PubMed

Farisco, Michele; Kotaleski, Jeanette H; Evers, Kathinka

2018-01-01

Modeling and simulations have gained a leading position in contemporary attempts to describe, explain, and quantitatively predict the human brain's operations. Computer models are highly sophisticated tools developed to achieve an integrated knowledge of the brain with the aim of overcoming the actual fragmentation resulting from different neuroscientific approaches. In this paper we investigate the plausibility of simulation technologies for emulation of consciousness and the potential clinical impact of large-scale brain simulation on the assessment and care of disorders of consciousness (DOCs), e.g., Coma, Vegetative State/Unresponsive Wakefulness Syndrome, Minimally Conscious State. Notwithstanding their technical limitations, we suggest that simulation technologies may offer new solutions to old practical problems, particularly in clinical contexts. We take DOCs as an illustrative case, arguing that the simulation of neural correlates of consciousness is potentially useful for improving treatments of patients with DOCs.

Large-Scale Brain Simulation and Disorders of Consciousness. Mapping Technical and Conceptual Issues

PubMed Central

Farisco, Michele; Kotaleski, Jeanette H.; Evers, Kathinka

2018-01-01

Modeling and simulations have gained a leading position in contemporary attempts to describe, explain, and quantitatively predict the human brain’s operations. Computer models are highly sophisticated tools developed to achieve an integrated knowledge of the brain with the aim of overcoming the actual fragmentation resulting from different neuroscientific approaches. In this paper we investigate the plausibility of simulation technologies for emulation of consciousness and the potential clinical impact of large-scale brain simulation on the assessment and care of disorders of consciousness (DOCs), e.g., Coma, Vegetative State/Unresponsive Wakefulness Syndrome, Minimally Conscious State. Notwithstanding their technical limitations, we suggest that simulation technologies may offer new solutions to old practical problems, particularly in clinical contexts. We take DOCs as an illustrative case, arguing that the simulation of neural correlates of consciousness is potentially useful for improving treatments of patients with DOCs. PMID:29740372

Ordering molecular genetic tests and reporting results: practices in laboratory and clinical settings.

PubMed

Lubin, Ira M; Caggana, Michele; Constantin, Carolyn; Gross, Susan J; Lyon, Elaine; Pagon, Roberta A; Trotter, Tracy L; Wilson, Jean Amos; McGovern, Margaret M

2008-09-01

Previous studies have suggested that patient care may be compromised as a consequence of poor communication between clinicians and laboratory professionals in cases in which molecular genetic test results are reported. To understand better the contributing factors to such compromised care, we investigated both pre- and postanalytical processes using cystic fibrosis mutation analysis as our model. We found that although the majority of test requisition forms requested patient/family information that was necessary for the proper interpretation of test results, in many cases, these data were not provided by the individuals filling out the forms. We found instances in which result reports for simulated diagnostic testing described individuals as carriers where only a single mutation was found with no comment pertaining to a diagnosis of cystic fibrosis. Similarly, reports based on simulated scenarios for carrier testing were problematic when no mutations were identified, and the patient's race/ethnicity and family history were not discussed in reference to residual risk of disease. Remarkably, a pilot survey of obstetrician-gynecologists revealed that office staff, including secretaries, often helped order genetic tests and reported test results to patients, raising questions about what efforts are undertaken to ensure personnel competency. These findings are reviewed in light of what efforts should be taken to improve the quality of test-ordering and result-reporting practices.

Simulation of patient encounters using a virtual patient in periodontology instruction of dental students: design, usability, and learning effect in history-taking skills.

PubMed

Schittek Janda, M; Mattheos, N; Nattestad, A; Wagner, A; Nebel, D; Färbom, C; Lê, D-H; Attström, R

2004-08-01

Simulations are important educational tools in the development of health care competence. This study describes a virtual learning environment (VLE) for diagnosis and treatment planning in oral health care. The VLE is a web-based, database application where the learner uses free text communication on the screen to interact with patient data. The VLE contains forms for history taking, clinical images, clinical data and X-rays. After reviewing the patient information, the student proposes therapy and makes prognostic evaluations of the case in free text. A usability test of the application was performed with seven dental students. The usability test showed that the software responded with correct answers to the majority of the free text questions. The application is generic in its basic functions and can be adapted to other dental or medical subject areas. A randomised controlled trial was carried out with 39 students who attended instruction in history taking with problem-based learning cases, lectures and seminars. In addition, 16 of the 39 students were randomly chosen to practise history taking using the virtual patient prior to their first patient encounter. The performance of each student was recorded on video during the patient sessions. The type and order of the questions asked by the student and the degree of empathy displayed towards the patient were analysed systematically on the videos. The data indicate that students who also undertook history taking with a virtual patient asked more relevant questions, spent more time on patient issues, and performed a more complete history interview compared with students who had only undergone standard teaching. The students who had worked with the virtual patient also seemed to have more empathy for the patients than the students who had not. The practising of history taking with a virtual patient appears to improve the capability of dental students to take a relevant oral health history.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, H; Medin, P; Jiang, S

Purpose: In-treatment tumor localization is critical for the management of tumor motion in lung cancer radiotherapy. Conventional tumor-tracking methods using a kV or MV x-ray projection has limited contrast. To facilitate real-time, marker-less and low-dose in-treatment image tumor tracking, we propose a novel scheme using Compton scatter imaging. This study reports Monte Carlo (MC) simulations on this scheme for the purpose of proof-of-principle. Methods: A slit x-ray beam along the patient superior-inferior (SI) direction is directed to the patient, intersecting the patient lung at a 2D plane containing majority part of the tumor motion trajectory. X-ray photons are scattered duemore » to Compton effect from this plane, which are spatially collimated by, e.g., a pinhole, on one side of the plane and then captured by a detector behind it. The captured image, after correcting for x-ray attenuation and scatter angle variation, reflects the electron density, which allows visualization of the instantaneous anatomy on this plane. We performed MC studies on a phantom and a patient case for the initial test of this proposed method. Results: In the phantom case, the contrast-resolution calculated using tumor/lung as foreground/background for kV fluoroscopy, cone-beam CT, and scattering image were 0.0625, 0.6993, and 0.5290, respectively. In the patient case, tumor motion can be clearly observed in the scatter images. Compared to fluoroscopy, scattering imaging also significantly reduced imaging dose because of its narrower beam design. Conclusion: MC simulation studies demonstrated the potential of the proposed scheme in terms of capturing the instantaneous anatomy of a patient on a 2D plane. Clear visualization of the tumor will probably facilitate ‘marker-less’ and ‘real-time’ tumor tracking with low imaging dose. NIH (1R01CA154747-01, 1R21CA178787-01A1 and 1R21EB017978-01A1)« less

Introduction of virtual patients onto a final year anesthesia course: Hong Kong experience.

PubMed

Leung, Joseph Yc; Critchley, Lester Ah; Yung, Alex Lk; Kumta, Shekhar M

2011-01-01

e-Learning has revolutionized the way in which undergraduate medical education is delivered. One e-learning tool of note is the virtual patient (VP), a type of computer software that simulates real-life clinical scenarios, in which the learner emulates the role of health care provider to obtain the history, conduct examination, and make diagnoses and management decisions. VPs have been in use since 1993. Early designs were based on serial screen-cards of patient history, examination, investigations, diagnoses, treatment, and outcome, which the learner explored. With the development of web technology, VPs can now be accessed via the Internet and are more versatile, supporting different structural designs to suit a variety of learning objectives, and they can branch via different routes through a case. Using VPs has a number of advantages: 1) VPs improve access to learning material, 2) VPs help learners to acquire higher order cognitive skills like strategic thinking and decision making, 3) VPs provide a safe environment to practice, 4) VPs help to teach interdisciplinary care, and 5) VPs can be used instead of patients for examination. A number of well-known VP player systems are in use today: CASUS, CAMPUS, web-based Simulation of Patients, OpenLabyrinth, and vpSim. At the Chinese University of Hong Kong, we have also developed a web-based VP authoring and player system called Formative Assessment Case Studies (FACS), which is run by our Teaching and Learning Resources Centre. FACS has been integrated into Year-5 Anesthesia teaching since 2006. Three VP products have been developed: Anaesthesia FACS (six cases) that teaches preoperative assessment, Acute Pain Management FACS, and an eight-part longitudinal VP which tells the story of a patient's stay, and anesthesia care, for routine gynecological surgery. Students spend about 3 hours on each during a 2-week clinical attachment. Our VPs have been well received and have overcome problems of providing adequate clinical exposure.

Hypophosphatemic osteomalacia: a case simulating anklylosing spondylitis treated with anti-TNF therapy.

PubMed

Sivas, F; Yurdakul, F G; Durak, M; Hatipoğlu, G; Önal, E D; Bodur, H

2016-12-01

In this case, a young male patient diagnosed as hypophosphatemic osteomalacia and ankylosing spondylitis (AS) will be assessed by literature. A 32-year-old male patient who had been previously diagnosed as ankylosing spondylitis and hypophosphatemic osteomalacia was admitted to our clinic. In the beginning of the disease, he complained of pain on the first metatarsal bone and low back. Sacroiliac magnetic resonance (MR) images were interpreted as sacroiliitis. He was diagnosed as AS, and referred to many hospitals and received several therapies. He did not benefit from the treatment and his complaints worsened. The human leukocyte antigen (HLA) B-27 test was negative and alkaline phosphatase level was high. Old femur fractures were reported in the whole body bone scintigraphy. In addition, the patient was diagnosed with osteomalacia. While the patient was receiving vitamin D, oral phosphate, anti-tumor necrosis factor therapy was added. Patient's diagnosis was reevaluated. His final diagnosis was hypophosphatemic osteomalacia instead of ankylosing spondylitis.

Developing an efficient scheduling template of a chemotherapy treatment unit: A case study.

PubMed

Ahmed, Z; Elmekkawy, Ty; Bates, S

2011-01-01

This study was undertaken to improve the performance of a Chemotherapy Treatment Unit by increasing the throughput and reducing the average patient's waiting time. In order to achieve this objective, a scheduling template has been built. The scheduling template is a simple tool that can be used to schedule patients' arrival to the clinic. A simulation model of this system was built and several scenarios, that target match the arrival pattern of the patients and resources availability, were designed and evaluated. After performing detailed analysis, one scenario provide the best system's performance. A scheduling template has been developed based on this scenario. After implementing the new scheduling template, 22.5% more patients can be served. 1. CancerCare Manitoba is a provincially mandated cancer care agency. It is dedicated to provide quality care to those who have been diagnosed and are living with cancer. MacCharles Chemotherapy unit is specially built to provide chemotherapy treatment to the cancer patients of Winnipeg. In order to maintain an excellent service, it tries to ensure that patients get their treatment in a timely manner. It is challenging to maintain that goal because of the lack of a proper roster, the workload distribution and inefficient resource allotment. In order to maintain the satisfaction of the patients and the healthcare providers, by serving the maximum number of patients in a timely manner, it is necessary to develop an efficient scheduling template that matches the required demand with the availability of resources. This goal can be reached using simulation modelling. Simulation has proven to be an excellent modelling tool. It can be defined as building computer models that represent real world or hypothetical systems, and hence experimenting with these models to study system behaviour under different scenarios.1, 2 A study was undertaken at the Children's Hospital of Eastern Ontario to identify the issues behind the long waiting time of a emergency room.3 A 20---day field observation revealed that the availability of the staff physician and interaction affects the patient wait time. Jyväskylä et al.4 used simulation to test different process scenarios, allocate resources and perform activity---based cost analysis in the Emergency Department (ED) at the Central Hospital. The simulation also supported the study of a new operational method, named "triage-team" method without interrupting the main system. The proposed triage team method categorises the entire patient according to the urgency to see the doctor and allows the patient to complete the necessary test before being seen by the doctor for the first time. The simulation study showed that it will decrease the throughput time of the patient and reduce the utilisation of the specialist and enable the ordering all the tests the patient needs right after arrival, thus quickening the referral to treatment. Santibáñez et al.5 developed a discrete event simulation model of British Columbia Cancer Agency"s ambulatory care unit which was used to study the impact of scenarios considering different operational factors (delay in starting clinic), appointment schedule (appointment order, appointment adjustment, add---ons to the schedule) and resource allocation. It was found that the best outcomes were obtained when not one but multiple changes were implemented simultaneously. Sepúlveda et al.6 studied the M. D. Anderson Cancer Centre Orlando, which is a cancer treatment facility and built a simulation model to analyse and improve flow process and increase capacity in the main facility. Different scenarios were considered like, transferring laboratory and pharmacy areas, adding an extra blood draw room and applying different scheduling techniques of patients. The study shows that by increasing the number of short---term (four hours or less) patients in the morning could increase chair utilisation. Discrete event simulation also helps improve a service where staff are ignorant about the behaviour of the system as a whole; which can also be described as a real professional system. Niranjon et al.7 used simulation successfully where they had to face such constraints and lack of accessible data. Carlos et al. 8 used Total quality management and simulation - animation to improve the quality of the emergency room. Simulation was used to cover the key point of the emergency room and animation was used to indicate the areas of opportunity required. This study revealed that a long waiting time, overload personnel and increasing withdrawal rate of patients are caused by the lack of capacity in the emergency room. Baesler et al.9 developed a methodology for a cancer treatment facility to find stochastically a global optimum point for the control variables. A simulation model generated the output using a goal programming framework for all the objectives involved in the analysis. Later a genetic algorithm was responsible for performing the search for an improved solution. The control variables that were considered in this research are number of treatment chairs, number of drawing blood nurses, laboratory personnel, and pharmacy personnel. Guo et al. 10 presented a simulation framework considering demand for appointment, patient flow logic, distribution of resources, scheduling rules followed by the scheduler. The objective of the study was to develop a scheduling rule which will ensure that 95% of all the appointment requests should be seen within one week after the request is made to increase the level of patient satisfaction and balance the schedule of each doctor to maintain a fine harmony between "busy clinic" and "quiet clinic". Huschka et al.11 studied a healthcare system which was about to change their facility layout. In this case a simulation model study helped them to design a new healthcare practice by evaluating the change in layout before implementation. Historical data like the arrival rate of the patients, number of patients visited each day, patient flow logic, was used to build the current system model. Later, different scenarios were designed which measured the changes in the current layout and performance. Wijewickrama et al.12 developed a simulation model to evaluate appointment schedule (AS) for second time consultations and patient appointment sequence (PSEQ) in a multi---facility system. Five different appointment rule (ARULE) were considered: i) Baily; ii) 3Baily; iii) Individual (Ind); iv) two patients at a time (2AtaTime); v) Variable Interval and (V---I) rule. PSEQ is based on type of patients: Appointment patients (APs) and new patients (NPs). The different PSEQ that were studied in this study were: i) first--- come first---serve; ii) appointment patient at the beginning of the clinic (APBEG); iii) new patient at the beginning of the clinic (NPBEG); iv) assigning appointed and new patients in an alternating manner (ALTER); v) assigning a new patient after every five---appointment patients. Also patient no show (0% and 5%) and patient punctuality (PUNCT) (on---time and 10 minutes early) were also considered. The study found that ALTER---Ind. and ALTER5---Ind. performed best on 0% NOSHOW, on---time PUNCT and 5% NOSHOW, on---time PUNCT situation to reduce WT and IT per patient. As NOSHOW created slack time for waiting patients, their WT tends to reduce while IT increases due to unexpected cancellation. Earliness increases congestion whichin turn increases waiting time. Ramis et al.13 conducted a study of a Medical Imaging Center (MIC) to build a simulation model which was used to improve the patient journey through an imaging centre by reducing the wait time and making better use of the resources. The simulation model also used a Graphic User Interface (GUI) to provide the parameters of the centre, such as arrival rates, distances, processing times, resources and schedule. The simulation was used to measure the waiting time of the patients in different case scenarios. The study found that assigning a common function to the resource personnel could improve the waiting time of the patients. The objective of this study is to develop an efficient scheduling template that maximises the number of served patients and minimises the average patient's waiting time at the given resources availability. To accomplish this objective, we will build a simulation model which mimics the working conditions of the clinic. Then we will suggest different scenarios of matching the arrival pattern of the patients with the availability of the resources. Full experiments will be performed to evaluate these scenarios. Hence, a simple and practical scheduling template will be built based on the indentified best scenario. The developed simulation model is described in section 2, which consists of a description of the treatment room, and a description of the types of patients and treatment durations. In section 3, different improvement scenarios are described and their analysis is presented in section 4. Section 5 illustrates a scheduling template based on one of the improvement scenarios. Finally, the conclusion and future direction of our work is exhibited in section 6. 2. A simulation model represents the actual system and assists in visualising and evaluating the performance of the system under different scenarios without interrupting the actual system. Building a proper simulation model of a system consists of the following steps. Observing the system to understand the flow of the entities, key players, availability of resources and overall generic framework.Collecting the data on the number and type of entities, time consumed by the entities at each step of their journey, and availability of resources.After building the simulation model it is necessary to confirm that the model is valid. (ABSTRACT TRUNCATED)

Effects of Preoperative Simulation on Minimally Invasive Hybrid Lumbar Interbody Fusion.

PubMed

Rieger, Bernhard; Jiang, Hongzhen; Reinshagen, Clemens; Molcanyi, Marek; Zivcak, Jozef; Grönemeyer, Dietrich; Bosche, Bert; Schackert, Gabriele; Ruess, Daniel

2017-10-01

The main focus of this study was to evaluate how preoperative simulation affects the surgical work flow, radiation exposure, and outcome of minimally invasive hybrid lumbar interbody fusion (MIS-HLIF). A total of 132 patients who underwent single-level MIS-HLIF were enrolled in a cohort study design. Dose area product was analyzed in addition to surgical data. Once preoperative simulation was established, 66 cases (SIM cohort) were compared with 66 patients who had previously undergone MIS-HLIF without preoperative simulation (NO-SIM cohort). Dose area product was reduced considerably in the SIM cohort (320 cGy·cm 2 NO-SIM cohort: 470 cGy·cm 2 ; P < 0.01). Surgical time was shorter for the SIM cohort (155 minutes; NO-SIM cohort, 182 minutes; P < 0.05). SIM cohort had a better outcome in Numeric Rating Scale back at 6 months follow-up compared with the NO-SIM cohort (P < 0.05). Preoperative simulation reduced radiation exposure and resulted in less back pain at the 6 months follow-up time point. Preoperative simulation provided guidance in determining the correct cage height. Outcome controls enabled the surgeon to improve the procedure and the software algorithm. Copyright © 2017 Elsevier Inc. All rights reserved.

INCLUDING AORTIC VALVE MORPHOLOGY IN COMPUTATIONAL FLUID DYNAMICS SIMULATIONS: INITIAL FINDINGS AND APPLICATION TO AORTIC COARCTATION

PubMed Central

Wendell, David C.; Samyn, Margaret M.; Cava, Joseph R.; Ellwein, Laura M.; Krolikowski, Mary M.; Gandy, Kimberly L.; Pelech, Andrew N.; Shadden, Shawn C.; LaDisa, John F.

2012-01-01

Computational fluid dynamics (CFD) simulations quantifying thoracic aortic flow patterns have not included disturbances from the aortic valve (AoV). 80% of patients with aortic coarctation (CoA) have a bicuspid aortic valve (BAV) which may cause adverse flow patterns contributing to morbidity. Our objectives were to develop a method to account for the AoV in CFD simulations, and quantify its impact on local hemodynamics. The method developed facilitates segmentation of the AoV, spatiotemporal interpolation of segments, and anatomic positioning of segments at the CFD model inlet. The AoV was included in CFD model examples of a normal (tricuspid AoV) and a post-surgical CoA patient (BAV). Velocity, turbulent kinetic energy (TKE), time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) results were compared to equivalent simulations using a plug inlet profile. The plug inlet greatly underestimated TKE for both examples. TAWSS differences extended throughout the thoracic aorta for the CoA BAV, but were limited to the arch for the normal example. OSI differences existed mainly in the ascending aorta for both cases. The impact of AoV can now be included with CFD simulations to identify regions of deleterious hemodynamics thereby advancing simulations of the thoracic aorta one step closer to reality. PMID:22917990

Development and pilot of Case Manager: a virtual-patient experience for veterinary students.

PubMed

Byron, Julie K; Johnson, Susan E; Allen, L Clare V; Brilmyer, Cheryl; Griffiths, Robert P

2014-01-01

There is an increasing demand in veterinary education to engage students, teach and reinforce clinical reasoning, and provide access anytime/anywhere to quality learning opportunities. In addition, accrediting bodies are asking for more concrete documentation of essential clinical-skills outcomes. Unfortunately, during the clinical year in a referral hospital setting, students are at the mercy of chance regarding the types of cases they will encounter and the opportunities they will have to participate. Patient- and case-simulation technology is becoming more popular as a way to achieve these objectives in human and veterinary medical education. Many of the current options available to the veterinary medical education community to develop virtual-patient cases are too time-consuming, cost prohibitive, or difficult for the instructor or learner to use. In response, we developed a learning tool, Case Manager, which is low-cost and user-friendly. Case Manager was designed to meet the demands of veterinary education by providing students with an opportunity to cultivate clinical reasoning skills and allowing for real-time student feedback. We launched a pilot test with 37 senior veterinary medical students as part of their Small Animal Internal Medicine clinical rotation. Students reported that Case Manager increased their engagement with the material, improved diagnostic and problem-solving skills, and broadened their exposure to a variety of cases. In addition, students felt that Case Manager was superior to a more traditional, less interactive case presentation format.

Investigation of factors affecting hypothermic pelvic tissue cooling using bio-heat simulation based on MRI-segmented anatomic models.

PubMed

Lin, Yuting; Lin, Wei-Ching; Fwu, Peter T; Shih, Tzu-Ching; Yeh, Lee-Ren; Su, Min-Ying; Chen, Jeon-Hor

2015-10-01

This study applied a simulation method to map the temperature distribution based on magnetic resonance imaging (MRI) of individual patients, and investigated the influence of different pelvic tissue types as well as the choice of thermal property parameters on the efficiency of endorectal cooling balloon (ECB). MR images of four subjects with different prostate sizes and pelvic tissue compositions, including fatty tissue and venous plexus, were analyzed. The MR images acquired using endorectal coil provided a realistic geometry of deformed prostate that resembled the anatomy in the presence of ECB. A single slice with the largest two-dimensional (2D) cross-sectional area of the prostate gland was selected for analysis. The rectal wall, prostate gland, peri-rectal fatty tissue, peri-prostatic fatty tissue, peri-prostatic venous plexus, and urinary bladder were manually segmented. Pennes' bioheat thermal model was used to simulate the temperature distribution dynamics, by using an in-house finite element mesh based solver written in MATLAB. The results showed that prostate size and periprostatic venous plexus were two major factors affecting ECB cooling efficiency. For cases with negligible amount of venous plexus and small prostate, the average temperature in the prostate and neurovascular bundles could be cooled down to 25 °C within 30 min. For cases with abundant venous plexus and large prostate, the temperature could not reach 25 °C at the end of 3 h cooling. Large prostate made the cooling difficult to propagate through. The impact of fatty tissue on cooling effect was small. The filling of bladder with warm urine during the ECB cooling procedure did not affect the temperature in the prostate or NVB. In addition to the 2D simulation, in one case a 3D pelvic model was constructed for volumetric simulation. It was found that the 2D slice with the largest cross-sectional area of prostate had the most abundant venous plexus, and was the most difficult slice to cool, thus it may provide a conservative prediction of the cooling effect. This feasibility study demonstrated that the simulation tool could potentially be used for adjusting the setting of ECB for individual patients during hypothermic radical prostatectomy. Further studies using MR thermometry are required to validate the in silico results obtained using simulation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Investigation of factors affecting hypothermic pelvic tissue cooling using bio-heat simulation based on MRI-segmented anatomic models

PubMed Central

Lin, Yuting; Lin, Wei-Ching; Fwu, Peter T.; Shih, Tzu-Ching; Yeh, Lee-Ren; Su, Min-Ying; Chen, Jeon-Hor

2015-01-01

This study applied a simulation method to map the temperature distribution based on magnetic resonance imaging (MRI) of individual patients, and investigated the influence of different pelvic tissue types as well as the choice of thermal property parameters on the efficiency of endorectal cooling balloon (ECB). MR images of four subjects with different prostate sizes and pelvic tissue compositions, including fatty tissue and venous plexus, were analyzed. The MR images acquired using endorectal coil provided a realistic geometry of deformed prostate that resembled the anatomy in the presence of ECB. A single slice with the largest two-dimensional (2D) cross-sectional area of the prostate gland was selected for analysis. The rectal wall, prostate gland, peri-rectal fatty tissue, peri-prostatic fatty tissue, peri-prostatic venous plexus, and urinary bladder were manually segmented. Pennes’ bioheat thermal model was used to simulate the temperature distribution dynamics, by using an in-house finite element mesh based solver written in Matlab. The results showed that prostate size and periprostatic venous plexus were two major factors affecting ECB cooling efficiency. For cases with negligible amount of venous plexus and small prostate, the averaged temperature in the prostate and neurovascular bundles could be cooled down to 25°C within 30 minutes. For cases with abundant venous plexus and large prostate, the temperature could not reach 25°C at the end of 3 hours cooling. Large prostate made the cooling difficult to propagate through. The impact of fatty tissue on cooling effect was small. The filling of bladder with warm urine during the ECB cooling procedure did not affect the temperature in the prostate or NVB. In addition to the 2D simulation, in one case a 3D pelvic model was constructed for volumetric simulation. It was found that the 2D slice with the largest cross-sectional area of prostate had the most abundant venous plexus, and was the most difficult slice to cool, thus it may provide a conservative prediction of the cooling effect. This feasibility study demonstrated that the simulation tool could potentially be used for adjusting the setting of ECB for individual patients during hypothermic radical prostatectomy. Further studies using MR thermometry are required to validate the in silico results obtained using simulation. PMID:26198131

Bayesian mixture modeling for blood sugar levels of diabetes mellitus patients (case study in RSUD Saiful Anwar Malang Indonesia)

NASA Astrophysics Data System (ADS)

Budi Astuti, Ani; Iriawan, Nur; Irhamah; Kuswanto, Heri; Sasiarini, Laksmi

2017-10-01

Bayesian statistics proposes an approach that is very flexible in the number of samples and distribution of data. Bayesian Mixture Model (BMM) is a Bayesian approach for multimodal models. Diabetes Mellitus (DM) is more commonly known in the Indonesian community as sweet pee. This disease is one type of chronic non-communicable diseases but it is very dangerous to humans because of the effects of other diseases complications caused. WHO reports in 2013 showed DM disease was ranked 6th in the world as the leading causes of human death. In Indonesia, DM disease continues to increase over time. These research would be studied patterns and would be built the BMM models of the DM data through simulation studies where the simulation data built on cases of blood sugar levels of DM patients in RSUD Saiful Anwar Malang. The results have been successfully demonstrated pattern of distribution of the DM data which has a normal mixture distribution. The BMM models have succeed to accommodate the real condition of the DM data based on the data driven concept.

Case report: a work simulation program for a manual worker with a fracture injury.

PubMed

Chan, Chi-Chung; Chow, Jonathan H.W.

2000-01-01

Work rehabilitation programs targeting different client groups are available in nearly all major hospital occupational therapy departments in Hong Kong. Clients receiving work rehabilitation are referred from various out-patient clinics and other occupational therapists. Those clients experience limitation in work after their injuries or diseases and plan to return to work after rehabilitation. Program objectives are 1) to assist clients to reach maximum work capacity as rapidly as possible 2) to ensure clients return to work safely 3) to improve clients' work readiness. This case report describes an individualized work simulation program at a general hospital in Hong Kong provided for a typical client who is preparing to return to his worker role. Specific job analysis, goals and program rationale for the client are discussed.

Spontaneous Retroperitoneal Hematoma Simulating Ruptured Infrarenal Aortic Aneurysm in a Patient with End-Stage Renal Disease

PubMed Central

Li, JYY; Chan, YC; Qing, KX; Cheng, SW

2014-01-01

We reported a case of spontaneous retroperitoneal hematoma (SRH) simulating a ruptured infrarenal aortic aneurysm. A 72-year-old man with a history of infrarenal aortic aneurysm and end-stage renal disease on hemodialysis presented with malaise and nonspecific central abdominal pain and left loin discomfort. An emergency computed tomography scan showed a large retroperitoneal hematoma and clinical suspicion of ruptured infrarenal aortic aneurysm. However, the hematoma was discontinuous with the aneurysm sac and raised the clinical suspicion on dual pathology. The SRH was treated conservatively with transfusion of blood products, and the aneurysm was treated with nonemergency endovascular repair electively. This case demonstrates the importance of recognizing different clinical and radiological characteristics and be aware of dual pathology. PMID:28031651

Pretraining and posttraining assessment of residents' performance in the fourth accreditation council for graduate medical education competency: patient communication skills.

PubMed

Chandawarkar, Rajiv Y; Ruscher, Kimberly A; Krajewski, Aleksandra; Garg, Manish; Pfeiffer, Carol; Singh, Rekha; Longo, Walter E; Kozol, Robert A; Lesnikoski, Beth; Nadkarni, Prakash

2011-08-01

Structured communication curricula will improve surgical residents' ability to communicate effectively with patients. A prospective study approved by the institutional review board involved 44 University of Connecticut general surgery residents. Residents initially completed a written baseline survey to assess general communication skills awareness. In step 1 of the study, residents were randomized to 1 of 2 simulations using standardized patient instructors to mimic patients receiving a diagnosis of either breast or rectal cancer. The standardized patient instructors scored residents' communication skills using a case-specific content checklist and Master Interview Rating Scale. In step 2 of the study, residents attended a 3-part interactive program that comprised (1) principles of patient communication; (2) experiences of a surgeon (role as physician, patient, and patient's spouse); and (3) role-playing (3-resident groups played patient, physician, and observer roles and rated their own performance). In step 3, residents were retested as in step 1, using a crossover case design. Scores were analyzed using Wilcoxon signed rank test with a Bonferroni correction. Case-specific performance improved significantly, from a pretest content checklist median score of 8.5 (65%) to a posttest median of 11.0 (84%) (P = .005 by Wilcoxon signed rank test for paired ordinal data)(n = 44). Median Master Interview Rating Scale scores changed from 58.0 before testing (P = .10) to 61.5 after testing (P = .94). Difference between overall rectal cancer scores and breast cancer scores also were not significant. Patient communication skills need to be taught as part of residency training. With limited training, case-specific skills (herein, involving patients with cancer) are likely to improve more than general communication skills.

Virtual worlds and team training.

PubMed

Dev, Parvati; Youngblood, Patricia; Heinrichs, W Leroy; Kusumoto, Laura

2007-06-01

An important component of all emergency medicine residency programs is managing trauma effectively as a member of an emergency medicine team, but practice on live patients is often impractical and mannequin-based simulators are expensive and require all trainees to be physically present at the same location. This article describes a project to develop and evaluate a computer-based simulator (the Virtual Emergency Department) for distance training in teamwork and leadership in trauma management. The virtual environment provides repeated practice opportunities with life-threatening trauma cases in a safe and reproducible setting.

Cost-effectiveness analysis of 30-month vs 12-month dual antiplatelet therapy with clopidogrel and aspirin after drug-eluting stents in patients with acute coronary syndrome.

PubMed

Jiang, Minghuan; You, Joyce H S

2017-10-01

Continuation of dual antiplatelet therapy (DAPT) beyond 1 year reduces late stent thrombosis and ischemic events after drug-eluting stents (DES) but increases risk of bleeding. We hypothesized that extending DAPT from 12 months to 30 months in patients with acute coronary syndrome (ACS) after DES is cost-effective. A lifelong decision-analytic model was designed to simulate 2 antiplatelet strategies in event-free ACS patients who had completed 12-month DAPT after DES: aspirin monotherapy (75-162 mg daily) and continuation of DAPT (clopidogrel 75 mg daily plus aspirin 75-162 mg daily) for 18 months. Clinical event rates, direct medical costs, and quality-adjusted life-years (QALYs) gained were the primary outcomes from the US healthcare provider perspective. Base-case results showed DAPT continuation gained higher QALYs (8.1769 vs 8.1582 QALYs) at lower cost (USD42 982 vs USD44 063). One-way sensitivity analysis found that base-case QALYs were sensitive to odds ratio (OR) of cardiovascular death with DAPT continuation and base-case cost was sensitive to OR of nonfatal stroke with DAPT continuation. DAPT continuation remained cost-effective when the ORs of nonfatal stroke and cardiovascular death were below 1.241 and 1.188, respectively. In probabilistic sensitivity analysis, DAPT continuation was the preferred strategy in 74.75% of 10 000 Monte Carlo simulations at willingness-to-pay threshold of 50 000 USD/QALYs. Continuation of DAPT appears to be cost-effective in ACS patients who were event-free for 12-month DAPT after DES. The cost-effectiveness of DAPT for 30 months was highly subject to the OR of nonfatal stroke and OR of death with DAPT continuation. © 2017 Wiley Periodicals, Inc.

Is lecture dead? A preliminary study of medical students' evaluation of teaching methods in the preclinical curriculum.

PubMed

Zinski, Anne; Blackwell, Kristina T C Panizzi Woodley; Belue, F Mike; Brooks, William S

2017-09-22

To investigate medical students' perceptions of lecture and non-lecture-based instructional methods and compare preferences for use and quantity of each during preclinical training. We administered a survey to first- and second-year undergraduate medical students at the University of Alabama School of Medicine in Birmingham, Alabama, USA aimed to evaluate preferred instructional methods.  Using a cross-sectional study design, Likert scale ratings and student rankings were used to determine preferences among lecture, laboratory, team-based learning, simulation, small group case-based learning, large group case-based learning, patient presentation, and peer teaching. We calculated mean ratings for each instructional method and used chi-square tests to compare proportions of first- and second-year cohorts who ranked each in their top 5 preferred methods. Among participating students, lecture (M=3.6, SD=1.0), team based learning (M=4.2, SD=1.0), simulation (M=4.0, SD=1.0), small group case-based learning (M=3.8, SD=1.0), laboratory (M=3.6, SD=1.0), and patient presentation (M=3.8, SD=0.9) received higher scores than other instructional methods. Overall, second-year students ranked lecture lower (χ 2 (1, N=120) =16.33, p<0.0001) and patient presentation higher (χ 2 (1, N=120) =3.75, p=0.05) than first-year students. While clinically-oriented teaching methods were preferred by second-year medical students, lecture-based instruction was popular among first-year students. Results warrant further investigation to determine the ideal balance of didactic methods in undergraduate medical education, specifically curricula that employ patient-oriented instruction during the second preclinical year.

Quantitative measurement of interocular suppression in anisometropic amblyopia: a case-control study.

PubMed

Li, Jinrong; Hess, Robert F; Chan, Lily Y L; Deng, Daming; Yang, Xiao; Chen, Xiang; Yu, Minbin; Thompson, Benjamin

2013-08-01

The aims of this study were to assess (1) the relationship between interocular suppression and visual function in patients with anisometropic amblyopia, (2) whether suppression can be simulated in matched controls using monocular defocus or neutral density filters, (3) the effects of spectacle or rigid gas-permeable contact lens correction on suppression in patients with anisometropic amblyopia, and (4) the relationship between interocular suppression and outcomes of occlusion therapy. Case-control study (aims 1-3) and cohort study (aim 4). Forty-five participants with anisometropic amblyopia and 45 matched controls (mean age, 8.8 years for both groups). Interocular suppression was assessed using Bagolini striated lenses, neutral density filters, and an objective psychophysical technique that measures the amount of contrast imbalance between the 2 eyes that is required to overcome suppression (dichoptic motion coherence thresholds). Visual acuity was assessed using a logarithm minimum angle of resolution tumbling E chart and stereopsis using the Randot preschool test. Interocular suppression assessed using dichoptic motion coherence thresholds. Patients exhibited significantly stronger suppression than controls, and stronger suppression was correlated significantly with poorer visual acuity in amblyopic eyes. Reducing monocular acuity in controls to match that of cases using neutral density filters (luminance reduction) resulted in levels of interocular suppression comparable with that in patients. This was not the case for monocular defocus (optical blur). Rigid gas-permeable contact lens correction resulted in less suppression than spectacle correction, and stronger suppression was associated with poorer outcomes after occlusion therapy. Interocular suppression plays a key role in the visual deficits associated with anisometropic amblyopia and can be simulated in controls by inducing a luminance difference between the eyes. Accurate quantification of suppression using the dichoptic motion coherence threshold technique may provide useful information for the management and treatment of anisometropic amblyopia. Proprietary or commercial disclosure may be found after the references. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Virtual Surgery for Conduit Reconstruction of the Right Ventricular Outflow Tract.

PubMed

Ong, Chin Siang; Loke, Yue-Hin; Opfermann, Justin; Olivieri, Laura; Vricella, Luca; Krieger, Axel; Hibino, Narutoshi

2017-05-01

Virtual surgery involves the planning and simulation of surgical reconstruction using three-dimensional (3D) modeling based upon individual patient data, augmented by simulation of planned surgical alterations including implantation of devices or grafts. Here we describe a case in which virtual cardiac surgery aided us in determining the optimal conduit size to use for the reconstruction of the right ventricular outflow tract. The patient is a young adolescent male with a history of tetralogy of Fallot with pulmonary atresia, requiring right ventricle-to-pulmonary artery (RV-PA) conduit replacement. Utilizing preoperative magnetic resonance imaging data, virtual surgery was undertaken to construct his heart in 3D and to simulate the implantation of three different sizes of RV-PA conduit (18, 20, and 22 mm). Virtual cardiac surgery allowed us to predict the ability to implant a conduit of a size that would likely remain adequate in the face of continued somatic growth and also allow for the possibility of transcatheter pulmonary valve implantation at some time in the future. Subsequently, the patient underwent uneventful conduit change surgery with implantation of a 22-mm Hancock valved conduit. As predicted, the intrathoracic space was sufficient to accommodate the relatively large conduit size without geometric distortion or sternal compression. Virtual cardiac surgery gives surgeons the ability to simulate the implantation of prostheses of different sizes in relation to the dimensions of a specific patient's own heart and thoracic cavity in 3D prior to surgery. This can be very helpful in predicting optimal conduit size, determining appropriate timing of surgery, and patient education.

Comprehensive economic evaluation of thermotherapy for the treatment of cutaneous leishmaniasis in Colombia.

PubMed

Cardona-Arias, Jaiberth Antonio; López-Carvajal, Liliana; Tamayo-Plata, Mery Patricia; Vélez, Iván Darío

2018-01-29

Cutaneous leishmaniasis causes a high disease burden in Colombia, and available treatments present systemic toxicity, low patient compliance, contraindications, and high costs. The purpose of this study was to estimate the cost-effectiveness of thermotherapy versus Glucantime in patients with cutaneous leishmaniasis in Colombia. Cost-effectiveness study from an institutional perspective in 8133 incident cases. Data on therapeutic efficacy and safety were included, calculating standard costs; the outcomes were disability adjusted life years (DALYs) and the number of patients cured. The information sources were the Colombian Public Health Surveillance System, disease burden studies, and one meta-analysis of controlled clinical trials. Incremental cost-effectiveness was determined, and uncertainty was evaluated with tornado diagrams and Monte Carlo simulations. Thermotherapy would generate costs of US$ 501,621; the handling of adverse effects, US$ 29,224; and therapeutic failures, US$ 300,053. For Glucantime, these costs would be US$ 2,731,276, US$ 58,254, and US$ 406,298, respectively. With thermotherapy, the cost would be US$ 2062 per DALY averted and US$ 69 per patient cured; with Glucantime, the cost would be US$ 4241 per DALY averted and US$ 85 per patient cured. In Monte Carlo simulations, thermotherapy was the dominant strategy for DALYs averted in 67.9% of cases and highly cost-effective for patients cured in 72%. In Colombia, thermotherapy can be included as a cost-effective strategy for the management of cutaneous leishmaniasis. Its incorporation into clinical practice guidelines could represent savings of approximately US$ 10,488 per DALY averted and costs of US$ 116 per additional patient cured, compared to the use of Glucantime. These findings show the relevance of the incorporation of this treatment in our country and others with similar parasitological, clinical, and epidemiological patterns.

Computational replication of the patient-specific stenting procedure for coronary artery bifurcations: From OCT and CT imaging to structural and hemodynamics analyses.

PubMed

Chiastra, Claudio; Wu, Wei; Dickerhoff, Benjamin; Aleiou, Ali; Dubini, Gabriele; Otake, Hiromasa; Migliavacca, Francesco; LaDisa, John F

2016-07-26

The optimal stenting technique for coronary artery bifurcations is still debated. With additional advances computational simulations can soon be used to compare stent designs or strategies based on verified structural and hemodynamics results in order to identify the optimal solution for each individual's anatomy. In this study, patient-specific simulations of stent deployment were performed for 2 cases to replicate the complete procedure conducted by interventional cardiologists. Subsequent computational fluid dynamics (CFD) analyses were conducted to quantify hemodynamic quantities linked to restenosis. Patient-specific pre-operative models of coronary bifurcations were reconstructed from CT angiography and optical coherence tomography (OCT). Plaque location and composition were estimated from OCT and assigned to models, and structural simulations were performed in Abaqus. Artery geometries after virtual stent expansion of Xience Prime or Nobori stents created in SolidWorks were compared to post-operative geometry from OCT and CT before being extracted and used for CFD simulations in SimVascular. Inflow boundary conditions based on body surface area, and downstream vascular resistances and capacitances were applied at branches to mimic physiology. Artery geometries obtained after virtual expansion were in good agreement with those reconstructed from patient images. Quantitative comparison of the distance between reconstructed and post-stent geometries revealed a maximum difference in area of 20.4%. Adverse indices of wall shear stress were more pronounced for thicker Nobori stents in both patients. These findings verify structural analyses of stent expansion, introduce a workflow to combine software packages for solid and fluid mechanics analysis, and underscore important stent design features from prior idealized studies. The proposed approach may ultimately be useful in determining an optimal choice of stent and position for each patient. Copyright © 2015 Elsevier Ltd. All rights reserved.

Respiratory-gated CT as a tool for the simulation of breathing artifacts in PET and PET/CT.

PubMed

Hamill, J J; Bosmans, G; Dekker, A

2008-02-01

Respiratory motion in PET and PET/CT blurs the images and can cause attenuation-related errors in quantitative parameters such as standard uptake values. In rare instances, this problem even causes localization errors and the disappearance of tumors that should be detectable. Attenuation errors are severe near the diaphragm and can be enhanced when the attenuation correction is based on a CT series acquired during a breath-hold. To quantify the errors and identify the parameters associated with them, the authors performed a simulated PET scan based on respiratory-gated CT studies of five lung cancer patients. Diaphragmatic motion ranged from 8 to 25 mm in the five patients. The CT series were converted to 511-keV attenuation maps which were forward-projected and exponentiated to form sinograms of PET attenuation factors at each phase of respiration. The CT images were also segmented to form a PET object, moving with the same motion as the CT series. In the moving PET object, spherical 20 mm mobile tumors were created in the vicinity of the dome of the liver and immobile 20 mm tumors in the midchest region. The moving PET objects were forward-projected and attenuated, then reconstructed in several ways: phase-matched PET and CT, gated PET with ungated CT, ungated PET with gated CT, and conventional PET. Spatial resolution and statistical noise were not modeled. In each case, tumor uptake recovery factor was defined by comparing the maximum reconstructed pixel value with the known correct value. Mobile 10 and 30 mm tumors were also simulated in the case of a patient with 11 mm of breathing motion. Phase-matched gated PET and CT gave essentially perfect PET reconstructions in the simulation. Gated PET with ungated CT gave tumors of the correct shape, but recovery was too large by an amount that depended on the extent of the motion, as much as 90% for mobile tumors and 60% for immobile tumors. Gated CT with ungated PET resulted in blurred tumors and caused recovery errors between -50% and +75%. Recovery in clinical scans would be 0%-20% lower than stated because spatial resolution was not included in the simulation. Mobile tumors near the dome of the liver were subject to the largest errors in either case. Conventional PET for 20 mm tumors was quantitative in cases of motion less than 15 mm because of canceling errors in blurring and attenuation, but the recovery factors were too low by as much as 30% in cases of motion greater than 15 mm. The 10 mm tumors were blurred by motion to a greater extent, causing a greater SUV underestimation than in the case of 20 mm tumors, and the 30 mm tumors were blurred less. Quantitative PET imaging near the diaphragm requires proper matching of attenuation information to the emission information. The problem of missed tumors near the diaphragm can be reduced by acquiring attenuation-correction information near end expiration. A simple PET/CT protocol requiring no gating equipment also addresses this problem.

Effects of interactive instructional techniques in a web-based peripheral nervous system component for human anatomy.

PubMed

Allen, Edwin B; Walls, Richard T; Reilly, Frank D

2008-02-01

This study investigated the effects of interactive instructional techniques in a web-based peripheral nervous system (PNS) component of a first year medical school human anatomy course. Existing data from 9 years of instruction involving 856 students were used to determine (1) the effect of web-based interactive instructional techniques on written exam item performance and (2) differences between student opinions of the benefit level of five different types of interactive learning objects used. The interactive learning objects included Patient Case studies, review Games, Simulated Interactive Patients (SIP), Flashcards, and unit Quizzes. Exam item analysis scores were found to be significantly higher (p < 0.05) for students receiving the instructional treatment incorporating the web-based interactive learning objects than for students not receiving this treatment. Questionnaires using a five-point Likert scale were analysed to determine student opinion ratings of the interactive learning objects. Students reported favorably on the benefit level of all learning objects. Students rated the benefit level of the Simulated Interactive Patients (SIP) highest, and this rating was significantly higher (p < 0.05) than all other learning objects. This study suggests that web-based interactive instructional techniques improve student exam performance. Students indicated a strong acceptance of Simulated Interactive Patient learning objects.

[Model for unplanned self extubation of ICU patients using system dynamics approach].

PubMed

Song, Yu Gil; Yun, Eun Kyoung

2015-04-01

In this study a system dynamics methodology was used to identify correlation and nonlinear feedback structure among factors affecting unplanned extubation (UE) of ICU patients and to construct and verify a simulation model. Factors affecting UE were identified through a theoretical background established by reviewing literature and preceding studies and referencing various statistical data. Related variables were decided through verification of content validity by an expert group. A causal loop diagram (CLD) was made based on the variables. Stock & Flow modeling using Vensim PLE Plus Version 6.0 b was performed to establish a model for UE. Based on the literature review and expert verification, 18 variables associated with UE were identified and CLD was prepared. From the prepared CLD, a model was developed by converting to the Stock & Flow Diagram. Results of the simulation showed that patient stress, patient in an agitated state, restraint application, patient movability, and individual intensive nursing were variables giving the greatest effect to UE probability. To verify agreement of the UE model with real situations, simulation with 5 cases was performed. Equation check and sensitivity analysis on TIME STEP were executed to validate model integrity. Results show that identification of a proper model enables prediction of UE probability. This prediction allows for adjustment of related factors, and provides basic data do develop nursing interventions to decrease UE.

Tolerance design of patient-specific range QA using the DMAIC framework in proton therapy.

PubMed

Rah, Jeong-Eun; Shin, Dongho; Manger, Ryan P; Kim, Tae Hyun; Oh, Do Hoon; Kim, Dae Yong; Kim, Gwe-Ya

2018-02-01

To implement the DMAIC (Define-Measure-Analyze-Improve-Control) can be used for customizing the patient-specific QA by designing site-specific range tolerances. The DMAIC framework (process flow diagram, cause and effect, Pareto chart, control chart, and capability analysis) were utilized to determine the steps that need focus for improving the patient-specific QA. The patient-specific range QA plans were selected according to seven treatment site groups, a total of 1437 cases. The process capability index, C pm was used to guide the tolerance design of patient site-specific range. For prostate field, our results suggested that the patient range measurements were capable at the current tolerance level of ±1 mm in clinical proton plans. For other site-specific ranges, we analyzed that the tolerance tends to be overdesigned to insufficient process capability calculated by the patient-specific QA data. The customized tolerances were calculated for treatment sites. Control charts were constructed to simulate the patient QA time before and after the new tolerances were implemented. It is found that the total simulation QA time was decreased on average of approximately 20% after establishing new site-specific range tolerances. We simulated the financial impact of this project. The QA failure for whole process in proton therapy would lead up to approximately 30% increase in total cost. DMAIC framework can be used to provide an effective QA by setting customized tolerances. When tolerance design is customized, the quality is reasonably balanced with time and cost demands. © 2017 American Association of Physicists in Medicine.

Images created in a model eye during simulated cataract surgery can be the basis for images perceived by patients during cataract surgery

PubMed Central

Inoue, M; Uchida, A; Shinoda, K; Taira, Y; Noda, T; Ohnuma, K; Bissen-Miyajima, H; Hirakata, A

2014-01-01

Purpose To evaluate the images created in a model eye during simulated cataract surgery. Patients and methods This study was conducted as a laboratory investigation and interventional case series. An artificial opaque lens, a clear intraocular lens (IOL), or an irrigation/aspiration (I/A) tip was inserted into the ‘anterior chamber' of a model eye with the frosted posterior surface corresponding to the retina. Video images were recorded of the posterior surface of the model eye from the rear during simulated cataract surgery. The video clips were shown to 20 patients before cataract surgery, and the similarity of their visual perceptions to these images was evaluated postoperatively. Results The images of the moving lens fragments and I/A tip and the insertion of the IOL were seen from the rear. The image through the opaque lens and the IOL without moving objects was the light of the surgical microscope from the rear. However, when the microscope light was turned off after IOL insertion, the images of the microscope and operating room were observed by the room illumination from the rear. Seventy percent of the patients answered that the visual perceptions of moving lens fragments were similar to the video clips and 55% reported similarity with the IOL insertion. Eighty percent of the patients recommended that patients watch the video clip before their scheduled cataract surgery. Conclusions The patients' visual perceptions during cataract surgery can be reproduced in the model eye. Watching the video images preoperatively may help relax the patients during surgery. PMID:24788007

A virtual reality patient simulation system for teaching emergency response skills to U.S. Navy medical providers.

PubMed

Freeman, K M; Thompson, S F; Allely, E B; Sobel, A L; Stansfield, S A; Pugh, W M

2001-01-01

Rapid and effective medical intervention in response to civil and military-related disasters is crucial for saving lives and limiting long-term disability. Inexperienced providers may suffer in performance when faced with limited supplies and the demands of stabilizing casualties not generally encountered in the comparatively resource-rich hospital setting. Head trauma and multiple injury cases are particularly complex to diagnose and treat, requiring the integration and processing of complex multimodal data. In this project, collaborators adapted and merged existing technologies to produce a flexible, modular patient simulation system with both three-dimensional virtual reality and two-dimensional flat screen user interfaces for teaching cognitive assessment and treatment skills. This experiential, problem-based training approach engages the user in a stress-filled, high fidelity world, providing multiple learning opportunities within a compressed period of time and without risk. The system simulates both the dynamic state of the patient and the results of user intervention, enabling trainees to watch the virtual patient deteriorate or stabilize as a result of their decision-making speed and accuracy. Systems can be deployed to the field enabling trainees to practice repeatedly until their skills are mastered and to maintain those skills once acquired. This paper describes the technologies and the process used to develop the trainers, the clinical algorithms, and the incorporation of teaching points. We also characterize aspects of the actual simulation exercise through the lens of the trainee.

Fluid-structure interaction simulations of the Fontan procedure using variable wall properties.

PubMed

Long, C C; Hsu, M-C; Bazilevs, Y; Feinstein, J A; Marsden, A L

2012-05-01

Children born with single ventricle heart defects typically undergo a staged surgical procedure culminating in a total cavopulmonary connection (TCPC) or Fontan surgery. The goal of this work was to perform physiologic, patient-specific hemodynamic simulations of two post-operative TCPC patients by using fluid-structure interaction (FSI) simulations. Data from two patients are presented, and post-op anatomy is reconstructed from MRI data. Respiration rate, heart rate, and venous pressures are obtained from catheterization data, and inflow rates are obtained from phase contrast MRI data and are used together with a respiratory model. Lumped parameter (Windkessel) boundary conditions are used at the outlets. We perform FSI simulations by using an arbitrary Lagrangian-Eulerian finite element framework to account for motion of the blood vessel walls in the TCPC. This study is the first to introduce variable elastic properties for the different areas of the TCPC, including a Gore-Tex conduit. Quantities such as wall shear stresses and pressures at critical locations are extracted from the simulation and are compared with pressure tracings from clinical data as well as with rigid wall simulations. Hepatic flow distribution and energy efficiency are also calculated and compared for all cases. There is little effect of FSI on pressure tracings, hepatic flow distribution, and time-averaged energy efficiency. However, the effect of FSI on wall shear stress, instantaneous energy efficiency, and wall motion is significant and should be considered in future work, particularly for accurate prediction of thrombus formation. Copyright © 2012 John Wiley & Sons, Ltd.

Dual energy CT: How well can pseudo-monochromatic imaging reduce metal artifacts?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuchenbecker, Stefan, E-mail: stefan.kuchenbecker@dkfz.de; Faby, Sebastian; Sawall, Stefan

2015-02-15

Purpose: Dual Energy CT (DECT) provides so-called monoenergetic images based on a linear combination of the original polychromatic images. At certain patient-specific energy levels, corresponding to certain patient- and slice-dependent linear combination weights, e.g., E = 160 keV corresponds to α = 1.57, a significant reduction of metal artifacts may be observed. The authors aimed at analyzing the method for its artifact reduction capabilities to identify its limitations. The results are compared with raw data-based processing. Methods: Clinical DECT uses a simplified version of monochromatic imaging by linearly combining the low and the high kV images and by assigning an energymore » to that linear combination. Those pseudo-monochromatic images can be used by radiologists to obtain images with reduced metal artifacts. The authors analyzed the underlying physics and carried out a series expansion of the polychromatic attenuation equations. The resulting nonlinear terms are responsible for the artifacts, but they are not linearly related between the low and the high kV scan: A linear combination of both images cannot eliminate the nonlinearities, it can only reduce their impact. Scattered radiation yields additional noncanceling nonlinearities. This method is compared to raw data-based artifact correction methods. To quantify the artifact reduction potential of pseudo-monochromatic images, they simulated the FORBILD abdomen phantom with metal implants, and they assessed patient data sets of a clinical dual source CT system (100, 140 kV Sn) containing artifacts induced by a highly concentrated contrast agent bolus and by metal. In each case, they manually selected an optimal α and compared it to a raw data-based material decomposition in case of simulation, to raw data-based material decomposition of inconsistent rays in case of the patient data set containing contrast agent, and to the frequency split normalized metal artifact reduction in case of the metal implant. For each case, the contrast-to-noise ratio (CNR) was assessed. Results: In the simulation, the pseudo-monochromatic images yielded acceptable artifact reduction results. However, the CNR in the artifact-reduced images was more than 60% lower than in the original polychromatic images. In contrast, the raw data-based material decomposition did not significantly reduce the CNR in the virtual monochromatic images. Regarding the patient data with beam hardening artifacts and with metal artifacts from small implants the pseudo-monochromatic method was able to reduce the artifacts, again with the downside of a significant CNR reduction. More intense metal artifacts, e.g., as those caused by an artificial hip joint, could not be suppressed. Conclusions: Pseudo-monochromatic imaging is able to reduce beam hardening, scatter, and metal artifacts in some cases but it cannot remove them. In all cases, the CNR is significantly reduced, thereby rendering the method questionable, unless special post processing algorithms are implemented to restore the high CNR from the original images (e.g., by using a frequency split technique). Raw data-based dual energy decomposition methods should be preferred, in particular, because the CNR penalty is almost negligible.« less

Use of simulated electronic mail (e-mail) to assess medical student knowledge, professionalism, and communication skills.

PubMed

Christner, Jennifer G; Stansfield, R Brent; Schiller, Jocelyn H; Madenci, Arin; Keefer, Patricia M; Pituch, Ken

2010-10-01

Physicians communicate with patients using electronic mail (e-mail) with increasing frequency. Communication skills specific to e-mail do not appear to be taught explicitly in medical school. Therefore, the effect of an instructive session on effective e-mail communication was examined. Four simulated e-mails from a parent were developed. Students responded to an initial e-mail and then participated in a session on effective e-mail communication. Responses to a final e-mail were assessed using a rubric with subscores for medical knowledge, communication, and professionalism. Performance improved from the first to final e-mail response in the overall score and in each subscore. Improvement was sustained over the course of the academic year. Interrater reliability revealed good agreement. Communicating effectively with patients via e-mail is not intuitive but can be taught. It is feasible to introduce responses to a simulated e-mail case in a clinical clerkship as an assessment tool.

Scan, plan, print, practice, perform: Development and use of a patient-specific 3-dimensional printed model in adult cardiac surgery.

PubMed

Hermsen, Joshua L; Burke, Thomas M; Seslar, Stephen P; Owens, David S; Ripley, Beth A; Mokadam, Nahush A; Verrier, Edward D

2017-01-01

Static 3-dimensional printing is used for operative planning in cases that involve difficult anatomy. An interactive 3D print allowing deliberate surgical practice would represent an advance. Two patients with hypertrophic cardiomyopathy had 3-dimensional prints constructed preoperatively. Stereolithography files were generated by segmentation of chest computed tomographic scans. Prints were made with hydrogel material, yielding tissue-like models that can be surgically manipulated. Septal myectomy of the print was performed preoperatively in the simulation laboratory. Volumetric measures of print and patient resected specimens were compared. An assessment tool was developed and used to rate the utility of this process. Clinical and echocardiographic data were reviewed. There was congruence between volumes of print and patient resection specimens (patient 1, 3.5 cm 3 and 3.0 cm 3 , respectively; patient 2, 4.0 cm 3 and 4.0 cm 3 , respectively). The prints were rated useful (3.5 and 3.6 on a 5-point Likert scale) for preoperative visualization, planning, and practice. Intraoperative echocardiographic assessment showed adequate relief of left ventricular outflow tract obstruction (patient 1, 80 mm Hg to 18 mm Hg; patient 2, 96 mm Hg to 9 mm Hg). Both patients reported symptomatic improvement (New York Heart Association functional class III to class I). Three-dimensional printing of interactive hypertrophic cardiomyopathy heart models allows for patient-specific preoperative simulation. Resection volume relationships were congruous on both specimens and suggest evidence of construct validity. This model also holds educational promise for simulation of a low-volume, high-risk operation that is traditionally difficult to teach. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Hospital-Based Physicians' Intubation Decisions and Associated Mental Models when Managing a Critically and Terminally Ill Older Patient.

PubMed

Haliko, Shannon; Downs, Julie; Mohan, Deepika; Arnold, Robert; Barnato, Amber E

2018-04-01

Variation in the intensity of acute care treatment at the end of life is influenced more strongly by hospital and provider characteristics than patient preferences. We sought to describe physicians' mental models (i.e., thought processes) when encountering a simulated critically and terminally ill older patient, and to compare those models based on whether their treatment plan was patient preference-concordant or preference-discordant. Seventy-three hospital-based physicians from 3 academic medical centers engaged in a simulated patient encounter and completed a mental model interview while watching the video recording of their encounter. We used an "expert" model to code the interviews. We then used Kruskal-Wallis tests to compare the weighted mental model themes of physicians who provided preference-concordant treatment with those who provided preference-discordant treatment. Sixty-six (90%) physicians provided preference-concordant treatment and 7 (10%) provided preference-discordant treatment (i.e., they intubated the patient). Physicians who intubated the patient were more likely to emphasize the reversible and emergent nature of the patient situation (z = -2.111, P = 0.035), their own comfort (z = -2.764, P = 0.006), and rarely focused on explicit patient preferences (z = 2.380, P = 0.017). Post-decisional interviewing with audio/video prompting may induce hindsight bias. The expert model has not yet been validated and may not be exhaustive. The small sample size limits generalizability and power. Hospital-based physicians providing preference-discordant used a different mental model for decision making for a critically and terminally ill simulated case. These differences may offer targets for future interventions to promote preference-concordant care for seriously ill patients.

Motion compensation for MRI-compatible patient-mounted needle guide device: estimation of targeting accuracy in MRI-guided kidney cryoablations

NASA Astrophysics Data System (ADS)

Tokuda, Junichi; Chauvin, Laurent; Ninni, Brian; Kato, Takahisa; King, Franklin; Tuncali, Kemal; Hata, Nobuhiko

2018-04-01

Patient-mounted needle guide devices for percutaneous ablation are vulnerable to patient motion. The objective of this study is to develop and evaluate a software system for an MRI-compatible patient-mounted needle guide device that can adaptively compensate for displacement of the device due to patient motion using a novel image-based automatic device-to-image registration technique. We have developed a software system for an MRI-compatible patient-mounted needle guide device for percutaneous ablation. It features fully-automated image-based device-to-image registration to track the device position, and a device controller to adjust the needle trajectory to compensate for the displacement of the device. We performed: (a) a phantom study using a clinical MR scanner to evaluate registration performance; (b) simulations using intraoperative time-series MR data acquired in 20 clinical cases of MRI-guided renal cryoablations to assess its impact on motion compensation; and (c) a pilot clinical study in three patients to test its feasibility during the clinical procedure. FRE, TRE, and success rate of device-to-image registration were mm, mm, and 98.3% for the phantom images. The simulation study showed that the motion compensation reduced the targeting error for needle placement from 8.2 mm to 5.4 mm (p  <  0.0005) in patients under general anesthesia (GA), and from 14.4 mm to 10.0 mm () in patients under monitored anesthesia care (MAC). The pilot study showed that the software registered the device successfully in a clinical setting. Our simulation study demonstrated that the software system could significantly improve targeting accuracy in patients treated under both MAC and GA. Intraprocedural image-based device-to-image registration was feasible.

MCTP system model based on linear programming optimization of apertures obtained from sequencing patient image data maps.

PubMed

Ureba, A; Salguero, F J; Barbeiro, A R; Jimenez-Ortega, E; Baeza, J A; Miras, H; Linares, R; Perucha, M; Leal, A

2014-08-01

The authors present a hybrid direct multileaf collimator (MLC) aperture optimization model exclusively based on sequencing of patient imaging data to be implemented on a Monte Carlo treatment planning system (MC-TPS) to allow the explicit radiation transport simulation of advanced radiotherapy treatments with optimal results in efficient times for clinical practice. The planning system (called CARMEN) is a full MC-TPS, controlled through aMATLAB interface, which is based on the sequencing of a novel map, called "biophysical" map, which is generated from enhanced image data of patients to achieve a set of segments actually deliverable. In order to reduce the required computation time, the conventional fluence map has been replaced by the biophysical map which is sequenced to provide direct apertures that will later be weighted by means of an optimization algorithm based on linear programming. A ray-casting algorithm throughout the patient CT assembles information about the found structures, the mass thickness crossed, as well as PET values. Data are recorded to generate a biophysical map for each gantry angle. These maps are the input files for a home-made sequencer developed to take into account the interactions of photons and electrons with the MLC. For each linac (Axesse of Elekta and Primus of Siemens) and energy beam studied (6, 9, 12, 15 MeV and 6 MV), phase space files were simulated with the EGSnrc/BEAMnrc code. The dose calculation in patient was carried out with the BEAMDOSE code. This code is a modified version of EGSnrc/DOSXYZnrc able to calculate the beamlet dose in order to combine them with different weights during the optimization process. Three complex radiotherapy treatments were selected to check the reliability of CARMEN in situations where the MC calculation can offer an added value: A head-and-neck case (Case I) with three targets delineated on PET/CT images and a demanding dose-escalation; a partial breast irradiation case (Case II) solved with photon and electron modulated beams (IMRT + MERT); and a prostatic bed case (Case III) with a pronounced concave-shaped PTV by using volumetric modulated arc therapy. In the three cases, the required target prescription doses and constraints on organs at risk were fulfilled in a short enough time to allow routine clinical implementation. The quality assurance protocol followed to check CARMEN system showed a high agreement with the experimental measurements. A Monte Carlo treatment planning model exclusively based on maps performed from patient imaging data has been presented. The sequencing of these maps allows obtaining deliverable apertures which are weighted for modulation under a linear programming formulation. The model is able to solve complex radiotherapy treatments with high accuracy in an efficient computation time.

Evaluation of tumor localization in respiration motion-corrected cone-beam CT: Prospective study in lung

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dzyubak, Oleksandr; Kincaid, Russell; Hertanto, Agung

Purpose: Target localization accuracy of cone-beam CT (CBCT) images used in radiation treatment of respiratory disease sites is affected by motion artifacts (blurring and streaking). The authors have previously reported on a method of respiratory motion correction in thoracic CBCT at end expiration (EE). The previous retrospective study was limited to examination of reducing motion artifacts in a small number of patient cases. They report here on a prospective study in a larger group of lung cancer patients to evaluate respiratory motion-corrected (RMC)-CBCT ability to improve lung tumor localization accuracy and reduce motion artifacts in Linac-mounted CBCT images. A secondmore » study goal examines whether the motion correction derived from a respiration-correlated CT (RCCT) at simulation yields similar tumor localization accuracy at treatment. Methods: In an IRB-approved study, 19 lung cancer patients (22 tumors) received a RCCT at simulation, and on one treatment day received a RCCT, a respiratory-gated CBCT at end expiration, and a 1-min CBCT. A respiration monitor of abdominal displacement was used during all scans. In addition to a CBCT reconstruction without motion correction, the motion correction method was applied to the same 1-min scan. Projection images were sorted into ten bins based on abdominal displacement, and each bin was reconstructed to produce ten intermediate CBCT images. Each intermediate CBCT was deformed to the end expiration state using a motion model derived from RCCT. The deformed intermediate CBCT images were then added to produce a final RMC-CBCT. In order to evaluate the second study goal, the CBCT was corrected in two ways, one using a model derived from the RCCT at simulation [RMC-CBCT(sim)], the other from the RCCT at treatment [RMC-CBCT(tx)]. Image evaluation compared uncorrected CBCT, RMC-CBCT(sim), and RMC-CBCT(tx). The gated CBCT at end expiration served as the criterion standard for comparison. Using automatic rigid image registration, each CBCT was registered twice to the gated CBCT, first aligned to spine, second to tumor in lung. Localization discrepancy was defined as the difference between tumor and spine registration. Agreement in tumor localization with the gated CBCT was further evaluated by calculating a normalized cross correlation (NCC) of pixel intensities within a volume-of-interest enclosing the tumor in lung. Results: Tumor localization discrepancy was reduced with RMC-CBCT(tx) in 17 out of 22 cases relative to no correction. If one considers cases in which tumor motion is 5 mm or more in the RCCT, tumor localization discrepancy is reduced with RMC-CBCT(tx) in 14 out of 17 cases (p = 0.04), and with RMC-CBCT(sim) in 13 out of 17 cases (p = 0.05). Differences in localization discrepancy between correction models [RMC-CBCT(sim) vs RMC-CBCT(tx)] were less than 2 mm. In 21 out of 22 cases, improvement in NCC was higher with RMC-CBCT(tx) relative to no correction (p < 0.0001). Differences in NCC between RMC-CBCT(sim) and RMC-CBCT(tx) were small. Conclusions: Motion-corrected CBCT improves lung tumor localization accuracy and reduces motion artifacts in nearly all cases. Motion correction at end expiration using RCCT acquired at simulation yields similar results to that using a RCCT on the treatment day (2–3 weeks after simulation)« less

Evaluation of tumor localization in respiration motion-corrected cone-beam CT: prospective study in lung.

PubMed

Dzyubak, Oleksandr; Kincaid, Russell; Hertanto, Agung; Hu, Yu-Chi; Pham, Hai; Rimner, Andreas; Yorke, Ellen; Zhang, Qinghui; Mageras, Gig S

2014-10-01

Target localization accuracy of cone-beam CT (CBCT) images used in radiation treatment of respiratory disease sites is affected by motion artifacts (blurring and streaking). The authors have previously reported on a method of respiratory motion correction in thoracic CBCT at end expiration (EE). The previous retrospective study was limited to examination of reducing motion artifacts in a small number of patient cases. They report here on a prospective study in a larger group of lung cancer patients to evaluate respiratory motion-corrected (RMC)-CBCT ability to improve lung tumor localization accuracy and reduce motion artifacts in Linac-mounted CBCT images. A second study goal examines whether the motion correction derived from a respiration-correlated CT (RCCT) at simulation yields similar tumor localization accuracy at treatment. In an IRB-approved study, 19 lung cancer patients (22 tumors) received a RCCT at simulation, and on one treatment day received a RCCT, a respiratory-gated CBCT at end expiration, and a 1-min CBCT. A respiration monitor of abdominal displacement was used during all scans. In addition to a CBCT reconstruction without motion correction, the motion correction method was applied to the same 1-min scan. Projection images were sorted into ten bins based on abdominal displacement, and each bin was reconstructed to produce ten intermediate CBCT images. Each intermediate CBCT was deformed to the end expiration state using a motion model derived from RCCT. The deformed intermediate CBCT images were then added to produce a final RMC-CBCT. In order to evaluate the second study goal, the CBCT was corrected in two ways, one using a model derived from the RCCT at simulation [RMC-CBCT(sim)], the other from the RCCT at treatment [RMC-CBCT(tx)]. Image evaluation compared uncorrected CBCT, RMC-CBCT(sim), and RMC-CBCT(tx). The gated CBCT at end expiration served as the criterion standard for comparison. Using automatic rigid image registration, each CBCT was registered twice to the gated CBCT, first aligned to spine, second to tumor in lung. Localization discrepancy was defined as the difference between tumor and spine registration. Agreement in tumor localization with the gated CBCT was further evaluated by calculating a normalized cross correlation (NCC) of pixel intensities within a volume-of-interest enclosing the tumor in lung. Tumor localization discrepancy was reduced with RMC-CBCT(tx) in 17 out of 22 cases relative to no correction. If one considers cases in which tumor motion is 5 mm or more in the RCCT, tumor localization discrepancy is reduced with RMC-CBCT(tx) in 14 out of 17 cases (p = 0.04), and with RMC-CBCT(sim) in 13 out of 17 cases (p = 0.05). Differences in localization discrepancy between correction models [RMC-CBCT(sim) vs RMC-CBCT(tx)] were less than 2 mm. In 21 out of 22 cases, improvement in NCC was higher with RMC-CBCT(tx) relative to no correction (p < 0.0001). Differences in NCC between RMC-CBCT(sim) and RMC-CBCT(tx) were small. Motion-corrected CBCT improves lung tumor localization accuracy and reduces motion artifacts in nearly all cases. Motion correction at end expiration using RCCT acquired at simulation yields similar results to that using a RCCT on the treatment day (2-3 weeks after simulation).

In-situ medical simulation for pre-implementation testing of clinical service in a regional hospital in Hong Kong.

PubMed

Chen, P P; Tsui, N Tk; Fung, A Sw; Chiu, A Hf; Wong, W Cw; Leong, H T; Lee, P Sf; Lau, J Yw

2017-08-01

The implementation of a new clinical service is associated with anxiety and challenges that may prevent smooth and safe execution of the service. Unexpected issues may not be apparent until the actual clinical service commences. We present a novel approach to test the new clinical setting before actual implementation of our endovascular aortic repair service. In-situ simulation at the new clinical location would enable identification of potential process and system issues prior to implementation of the service. After preliminary planning, a simulation test utilising a case scenario with actual simulation of the entire care process was carried out to identify any logistic, equipment, settings or clinical workflow issues, and to trial a contingency plan for a surgical complication. All patient care including anaesthetic, surgical, and nursing procedures and processes were simulated and tested. Overall, 17 vital process and system issues were identified during the simulation as potential clinical concerns. They included difficult patient positioning, draping pattern, unsatisfactory equipment setup, inadequate critical surgical instruments, blood products logistics, and inadequate nursing support during crisis. In-situ simulation provides an innovative method to identify critical deficiencies and unexpected issues before implementation of a new clinical service. Life-threatening and serious practical issues can be identified and corrected before formal service commences. This article describes our experience with the use of simulation in pre-implementation testing of a clinical process or service. We found the method useful and would recommend it to others.

Simulated biologic intelligence used to predict length of stay and survival of burns.

PubMed

Frye, K E; Izenberg, S D; Williams, M D; Luterman, A

1996-01-01

From July 13, 1988, to May 14, 1995, 1585 patients with burns and no other injuries besides inhalation were treated; 4.5% did not survive. Artificial neural networks were trained on patient presentation data with known outcomes on 90% of the randomized cases. The remaining cases were then used to predict survival and length of stay in cases not trained on. Survival was predicted with more than 98% accuracy and length of stay to within a week with 72% accuracy in these cases. For anatomic area involved by burn, burns involving the feet, scalp, or both had the largest negative effect on the survival prediction. In survivors burns involving the buttocks, transport to this burn center by the military or by helicopter, electrical burns, hot tar burns, and inhalation were associated with increasing the length of stay prediction. Neural networks can be used to accurately predict the clinical outcome of a burn. What factors affect that prediction can be investigated.

Contrast‐enhanced computed tomography with myocardial three‐dimensional printing can guide treatment in symptomatic hypertrophic obstructive cardiomyopathy

PubMed Central

Hamatani, Yasuhiro; Amaki, Makoto; Kanzaki, Hideaki; Yamashita, Kizuku; Nakashima, Yasuteru; Shibata, Atsushi; Okada, Atsushi; Takahama, Hiroyuki; Hasegawa, Takuya; Shimahara, Yusuke; Sugano, Yasuo; Fujita, Tomoyuki; Shiraishi, Isao; Yasuda, Satoshi; Kobayashi, Junjiro

2017-01-01

Abstract Both surgical myectomy and percutaneous transluminal septal myocardial ablation are effective treatments for drug‐refractory symptomatic hypertrophic obstructive cardiomyopathy (HOCM). However, in some cases, it is not easy to elucidate the abnormal structure of left ventricular outflow obstruction to adopt these treatments. Here, we presented a young female patient with drug‐refractory symptomatic HOCM. In this case, contrast‐enhanced computed tomography enabled us to assess the suitability of percutaneous transluminal septal myocardial ablation. By creating three‐dimensional printed models using computed tomography data, we could also visualize intracardiac structure and simulate the surgical procedure. A multimodality assessment strategy is useful for evaluating patients complicated with drug‐refractory symptomatic HOCM. PMID:29154429

Clinical simulation as a boundary object in design of health IT-systems.

PubMed

Rasmussen, Stine Loft; Jensen, Sanne; Lyng, Karen Marie

2013-01-01

Healthcare organizations are very complex, holding numerous stakeholders with various approaches and goals towards the design of health IT-systems. Some of these differences may be approached by applying the concept of boundary objects in a participatory IT-design process. Traditionally clinical simulation provides the opportunity to evaluate the design and the usage of clinical IT-systems without endangering the patients and interrupting clinical work. In this paper we present how clinical simulation additionally holds the potential to function as a boundary object in the design process. The case points out that clinical simulation provides an opportunity for discussions and mutual learning among the various stakeholders involved in design of standardized electronic clinical documentation templates. The paper presents and discusses the use of clinical simulation in the translation, transfer and transformation of knowledge between various stakeholders in a large healthcare organization.

Computer-assisted preoperative simulation for positioning and fixation of plate in 2-stage procedure combining maxillary advancement by distraction technique and mandibular setback surgery.

PubMed

Suenaga, Hideyuki; Taniguchi, Asako; Yonenaga, Kazumichi; Hoshi, Kazuto; Takato, Tsuyoshi

2016-01-01

Computer-assisted preoperative simulation surgery is employed to plan and interact with the 3D images during the orthognathic procedure. It is useful for positioning and fixation of maxilla by a plate. We report a case of maxillary retrusion by a bilateral cleft lip and palate, in which a 2-stage orthognathic procedure (maxillary advancement by distraction technique and mandibular setback surgery) was performed following a computer-assisted preoperative simulation planning to achieve the positioning and fixation of the plate. A high accuracy was achieved in the present case. A 21-year-old male patient presented to our department with a complaint of maxillary retrusion following bilateral cleft lip and palate. Computer-assisted preoperative simulation with 2-stage orthognathic procedure using distraction technique and mandibular setback surgery was planned. The preoperative planning of the procedure resulted in good aesthetic outcomes. The error of the maxillary position was less than 1mm. The implementation of the computer-assisted preoperative simulation for the positioning and fixation of plate in 2-stage orthognathic procedure using distraction technique and mandibular setback surgery yielded good results. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Three-dimensional printed prototypes refine the anatomy of post-modified Norwood-1 complex aortic arch obstruction and allow presurgical simulation of the repair.

PubMed

Kiraly, Laszlo; Tofeig, Magdi; Jha, Neerod Kumar; Talo, Haitham

2016-02-01

Three-dimensional (3D) printed prototypes of malformed hearts have been used for education, communication, presurgical planning and simulation. We present a case of a 5-month old infant with complex obstruction at the neoaortic to transverse arch and descending aortic junction following the neonatal modified Norwood-1 procedure for hypoplastic left heart syndrome. Digital 3D models were created from a routine 64-slice CT dataset; then life-size solid and magnified hollow models were printed with a 3D printer. The solid model provided further insights into details of the anatomy, whereas the surgical approach and steps of the operation were simulated on the hollow model. Intraoperative assessment confirmed the anatomical accuracy of the 3D models. The operation was performed in accordance with preoperative simulation: sliding autologous flaps achieved relief of the obstruction without additional patching. Knowledge gained from the models fundamentally contributed to successful outcome and improved patient safety. This case study presents an effective use of 3D models in exploring complex spatial relationship at the aortic arch and in simulation-based planning of the operative procedure. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Stochastic resource allocation in emergency departments with a multi-objective simulation optimization algorithm.

PubMed

Feng, Yen-Yi; Wu, I-Chin; Chen, Tzu-Li

2017-03-01

The number of emergency cases or emergency room visits rapidly increases annually, thus leading to an imbalance in supply and demand and to the long-term overcrowding of hospital emergency departments (EDs). However, current solutions to increase medical resources and improve the handling of patient needs are either impractical or infeasible in the Taiwanese environment. Therefore, EDs must optimize resource allocation given limited medical resources to minimize the average length of stay of patients and medical resource waste costs. This study constructs a multi-objective mathematical model for medical resource allocation in EDs in accordance with emergency flow or procedure. The proposed mathematical model is complex and difficult to solve because its performance value is stochastic; furthermore, the model considers both objectives simultaneously. Thus, this study develops a multi-objective simulation optimization algorithm by integrating a non-dominated sorting genetic algorithm II (NSGA II) with multi-objective computing budget allocation (MOCBA) to address the challenges of multi-objective medical resource allocation. NSGA II is used to investigate plausible solutions for medical resource allocation, and MOCBA identifies effective sets of feasible Pareto (non-dominated) medical resource allocation solutions in addition to effectively allocating simulation or computation budgets. The discrete event simulation model of ED flow is inspired by a Taiwan hospital case and is constructed to estimate the expected performance values of each medical allocation solution as obtained through NSGA II. Finally, computational experiments are performed to verify the effectiveness and performance of the integrated NSGA II and MOCBA method, as well as to derive non-dominated medical resource allocation solutions from the algorithms.

Computer-based simulation training to improve learning outcomes in mannequin-based simulation exercises.

PubMed

Curtin, Lindsay B; Finn, Laura A; Czosnowski, Quinn A; Whitman, Craig B; Cawley, Michael J

2011-08-10

To assess the impact of computer-based simulation on the achievement of student learning outcomes during mannequin-based simulation. Participants were randomly assigned to rapid response teams of 5-6 students and then teams were randomly assigned to either a group that completed either computer-based or mannequin-based simulation cases first. In both simulations, students used their critical thinking skills and selected interventions independent of facilitator input. A predetermined rubric was used to record and assess students' performance in the mannequin-based simulations. Feedback and student performance scores were generated by the software in the computer-based simulations. More of the teams in the group that completed the computer-based simulation before completing the mannequin-based simulation achieved the primary outcome for the exercise, which was survival of the simulated patient (41.2% vs. 5.6%). The majority of students (>90%) recommended the continuation of simulation exercises in the course. Students in both groups felt the computer-based simulation should be completed prior to the mannequin-based simulation. The use of computer-based simulation prior to mannequin-based simulation improved the achievement of learning goals and outcomes. In addition to improving participants' skills, completing the computer-based simulation first may improve participants' confidence during the more real-life setting achieved in the mannequin-based simulation.

Health economic evaluation of plasma oxysterol screening in the diagnosis of Niemann-Pick Type C disease among intellectually disabled using discrete event simulation.

PubMed

van Karnebeek, Clara D M; Mohammadi, Tima; Tsao, Nicole; Sinclair, Graham; Sirrs, Sandra; Stockler, Sylvia; Marra, Carlo

2015-02-01

Recently a less invasive method of screening and diagnosing Niemann-Pick C (NP-C) disease has emerged. This approach involves the use of a metabolic screening test (oxysterol assay) instead of the current practice of clinical assessment of patients suspected of NP-C (review of medical history, family history and clinical examination for the signs and symptoms). Our objective is to compare costs and outcomes of plasma oxysterol screening versus current practice in diagnosis of NP-C disease among intellectually disabled (ID) patients using decision-analytic methods. A discrete event simulation model was conducted to follow ID patients through the diagnosis and treatment of NP-C, forecast the costs and effectiveness for a cohort of ID patients and compare the outcomes and costs in two different arms of the model: plasma oxysterol screening and routine diagnosis procedure (anno 2013) over 5 years of follow up. Data from published sources and clinical trials were used in simulation model. Unit costs and quality-adjusted life-years (QALYs) were discounted at a 3% annual rate in the base case analysis. Deterministic and probabilistic sensitivity analyses were conducted. The outcomes of the base case model showed that using plasma oxysterol screening for diagnosis of NP-C disease among ID patients is a dominant strategy. It would result in lower total cost and would slightly improve patients' quality of life. The average amount of cost saving was $3642 CAD and the incremental QALYs per each individual ID patient in oxysterol screening arm versus current practice of diagnosis NP-C was 0.0022 QALYs. Results of sensitivity analysis demonstrated robustness of the outcomes over the wide range of changes in model inputs. Whilst acknowledging the limitations of this study, we conclude that screening ID children and adolescents with oxysterol tests compared to current practice for the diagnosis of NP-C is a dominant strategy with clinical and economic benefits. The less costly, more sensitive and specific oxysterol test has potential to save costs to the healthcare system while improving patients' quality of life and may be considered as a routine tool in the NP-C diagnosis armamentarium for ID. Further research is needed to elucidate its effectiveness in patients presenting characteristics other than ID in childhood and adolescence. Copyright © 2014 Elsevier Inc. All rights reserved.

Incorporation of stochastic engineering models as prior information in Bayesian medical device trials.

PubMed

Haddad, Tarek; Himes, Adam; Thompson, Laura; Irony, Telba; Nair, Rajesh

2017-01-01

Evaluation of medical devices via clinical trial is often a necessary step in the process of bringing a new product to market. In recent years, device manufacturers are increasingly using stochastic engineering models during the product development process. These models have the capability to simulate virtual patient outcomes. This article presents a novel method based on the power prior for augmenting a clinical trial using virtual patient data. To properly inform clinical evaluation, the virtual patient model must simulate the clinical outcome of interest, incorporating patient variability, as well as the uncertainty in the engineering model and in its input parameters. The number of virtual patients is controlled by a discount function which uses the similarity between modeled and observed data. This method is illustrated by a case study of cardiac lead fracture. Different discount functions are used to cover a wide range of scenarios in which the type I error rates and power vary for the same number of enrolled patients. Incorporation of engineering models as prior knowledge in a Bayesian clinical trial design can provide benefits of decreased sample size and trial length while still controlling type I error rate and power.

Disease-Concordant Twins Empower Genetic Association Studies.

PubMed

Tan, Qihua; Li, Weilong; Vandin, Fabio

2017-01-01

Genome-wide association studies with moderate sample sizes are underpowered, especially when testing SNP alleles with low allele counts, a situation that may lead to high frequency of false-positive results and lack of replication in independent studies. Related individuals, such as twin pairs concordant for a disease, should confer increased power in genetic association analysis because of their genetic relatedness. We conducted a computer simulation study to explore the power advantage of the disease-concordant twin design, which uses singletons from disease-concordant twin pairs as cases and ordinary healthy samples as controls. We examined the power gain of the twin-based design for various scenarios (i.e., cases from monozygotic and dizygotic twin pairs concordant for a disease) and compared the power with the ordinary case-control design with cases collected from the unrelated patient population. Simulation was done by assigning various allele frequencies and allelic relative risks for different mode of genetic inheritance. In general, for achieving a power estimate of 80%, the sample sizes needed for dizygotic and monozygotic twin cases were one half and one fourth of the sample size of an ordinary case-control design, with variations depending on genetic mode. Importantly, the enriched power for dizygotic twins also applies to disease-concordant sibling pairs, which largely extends the application of the concordant twin design. Overall, our simulation revealed a high value of disease-concordant twins in genetic association studies and encourages the use of genetically related individuals for highly efficiently identifying both common and rare genetic variants underlying human complex diseases without increasing laboratory cost. © 2016 John Wiley & Sons Ltd/University College London.

Changes in self-efficacy, collective efficacy and patient outcome following interprofessional simulation training on postpartum haemorrhage.

PubMed

Egenberg, Signe; Øian, Pål; Eggebø, Torbjørn Moe; Arsenovic, Mirjana Grujic; Bru, Lars Edvin

2017-10-01

To examine whether interprofessional simulation training on management of postpartum haemorrhage enhances self-efficacy and collective efficacy and reduces the blood transfusion rate after birth. Postpartum haemorrhage is a leading cause of maternal morbidity and mortality worldwide, although it is preventable in most cases. Interprofessional simulation training might help improve the competence of health professionals dealing with postpartum haemorrhage, and more information is needed to determine its potential. Multimethod, quasi-experimental, pre-post intervention design. Interprofessional simulation training on postpartum haemorrhage was implemented for midwives, obstetricians and auxiliary nurses in a university hospital. Training included realistic scenarios and debriefing, and a measurement scale for perceived postpartum haemorrhage-specific self-efficacy, and collective efficacy was developed and implemented. Red blood cell transfusion was used as the dependent variable for improved patient outcome pre-post intervention. Self-efficacy and collective efficacy levels were significantly increased after training. The overall red blood cell transfusion rate did not change, but there was a significant reduction in the use of ≥5 units of blood products related to severe bleeding after birth. The study contributes to new knowledge on how simulation training through mastery and vicarious experiences, verbal persuasion and psychophysiological state might enhance postpartum haemorrhage-specific self-efficacy and collective efficacy levels and thereby predict team performance. The significant reduction in severe postpartum haemorrhage after training, indicated by reduction in ≥5 units of blood transfusions, corresponds well with the improvement in collective efficacy, and might reflect the emphasis on collective efforts to counteract severe cases of postpartum haemorrhage. Interprofessional simulation training in teams may contribute to enhanced prevention and management of postpartum haemorrhage, shown by a significant increase in perceived efficacy levels combined with an indicated reduction of severe postpartum haemorrhage after training. © 2016 John Wiley & Sons Ltd.

How detrimental is eye movement during photorefractive keratectomy to the patient's postoperative vision?

NASA Astrophysics Data System (ADS)

Taylor, Natalie M.; van Saarloos, Paul P.; Eikelboom, Robert H.

2000-06-01

This study aimed to gauge the effect of the patient's eye movement during Photo Refractive Keratectomy (PRK) on post- operative vision. A computer simulation of both the PRK procedure and the visual outcome has been performed. The PRK simulation incorporated the pattern of movement of the laser beam to perform a given correction, the beam characteristics, an initial corneal profile, and an eye movement scenario; and generated the corrected corneal profile. The regrowth of the epithelium was simulated by selecting the smoothing filter which, when applied to a corrected cornea with no patient eye movement, produced similar ray tracing results to the original corneal model. Ray tracing several objects, such as letters of various contrast and sizes was performed to assess the quality of the post-operative vision. Eye movement scenarios included no eye movement, constant decentration and normally distributed random eye movement of varying magnitudes. Random eye movement of even small amounts, such as 50 microns reduces the contrast sensitivity of the image. Constant decentration decenters the projected image on the retina, and in extreme cases can lead to astigmatism. Eye movements of the magnitude expected during laser refractive surgery have minimal effect on the final visual outcome.

[Complexity level simulation in the German diagnosis-related groups system: the financial effect of coding of comorbidity diagnostics in urology].

PubMed

Wenke, A; Gaber, A; Hertle, L; Roeder, N; Pühse, G

2012-07-01

Precise and complete coding of diagnoses and procedures is of value for optimizing revenues within the German diagnosis-related groups (G-DRG) system. The implementation of effective structures for coding is cost-intensive. The aim of this study was to prove whether higher costs can be refunded by complete acquisition of comorbidities and complications. Calculations were based on DRG data of the Department of Urology, University Hospital of Münster, Germany, covering all patients treated in 2009. The data were regrouped and subjected to a process of simulation (increase and decrease of patient clinical complexity levels, PCCL) with the help of recently developed software. In urology a strong dependency of quantity and quality of coding of secondary diagnoses on PCCL and subsequent profits was found. Departmental budgetary procedures can be optimized when coding is effective. The new simulation tool can be a valuable aid to improve profits available for distribution. Nevertheless, calculation of time use and financial needs by this procedure are subject to specific departmental terms and conditions. Completeness of coding of (secondary) diagnoses must be the ultimate administrative goal of patient case documentation in urology.

Spindle Cell Carcinoma of Nasal Cavity- A Case Report

PubMed Central

Mittal, Abhishek; Nagpal, Tapan

2016-01-01

Spindle Cell Carcinoma (SpCC), also known as Sarcomatoid Carcinoma, is a rare and peculiar biphasic malignant neoplasm that occurs mainly in the upper aero-digestive tract, mostly in larynx. SCC accounts for 3% of all squamous cell carcinomas (SCCs) in the head and neck region. It is a rare variant of SCC which shows spindled or pleomorphic tumour cells simulating a true sarcoma. We present a case report of SpCC nasal cavity in a 50-year-old female patient, presented with intermittent epistaxis from left nasal cavity. On physical examination, the patient had an ulcero-exophytic type of mass in the left nasal cavity and a smooth bulge on the left side of anterior hard palate. Patient underwent excision of nasal mass along with partial palatectomy by facial degloving approach and reconstruction of palate with naso-labial flap. The postoperative histopathological report showed SCC. Surgery forms the mainstay of treatment. Radiotherapy and Chemotherapy is warranted in order to improve treatment results. As only few cases have been reported, we report a case of this rare entity to contribute for better understanding and awareness of this rare malignancy. PMID:27190843

Potential impact of pharmacist interventions to reduce cost for Medicare Part D beneficiaries.

PubMed

Thatcher, Erin E; Vanwert, Elizabeth M; Erickson, Steven R

2013-06-01

The objective was to determine the impact of simulated pharmacist interventions on out-of-pocket cost, time to coverage gap, and cost per patient to the Medicare Part D program using actual patient cases from an adult general medicine clinic. Medication profiles of 100 randomly selected Medicare-eligible patients from a university-affiliated general internal medicine clinic were reviewed by a pharmacist to identify opportunities to cost-maximize the patients' therapies based on the plan. An online Part-D calculator, Aetna Medicare Rx Essentials, was used as the standard plan to determine medication cost and time to gap. The primary analysis was comparison of the patients' pre-review and post-review out-of-pocket cost, time to coverage gap, and cost to Medicare. A total of 65 patients had at least 1 simulated pharmacist cost intervention. The most common intervention was substituting for a less costly generic, followed by substituting a generic for a brand name. Projected patient cost savings was $476 per year. The average time to coverage gap was increased by 0.7 ±1.2 months. This study illustrates that the pharmacists may be able to reduce cost to some patients as well as to the Medicare Part D program.

The Many Faces of Patient-Centered Simulation: Implications for Researchers.

PubMed

Arnold, Jennifer L; McKenzie, Frederic Rick D; Miller, Jane Lindsay; Mancini, Mary E

2018-06-01

Patient-centered simulation for nonhealthcare providers is an emerging and innovative application for healthcare simulation. Currently, no consensus exists on what patient-centered simulation encompasses and outcomes research in this area is limited. Conceptually, patient-centered simulation aligns with the principles of patient- and family-centered care bringing this educational tool directly to patients and caregivers with the potential to improve patient care and outcomes. This descriptive article is a summary of findings presented at the 2nd International Meeting for Simulation in Healthcare Research Summit. Experts in the field delineated a categorization for better describing patient-centered simulation and reviewed the literature to identify a research agenda. Three types of patient-centered simulation patient-directed, patient-driven, and patient-specific are presented with research priorities identified for each. Patient-centered simulation has been shown to be an effective educational tool and has the potential to directly improve patient care outcomes. Presenting a typology for patient-centered simulation provides direction for future research.

Introduction of virtual patients onto a final year anesthesia course: Hong Kong experience

PubMed Central

Leung, Joseph YC; Critchley, Lester AH; Yung, Alex LK; Kumta, Shekhar M

2011-01-01

e-Learning has revolutionized the way in which undergraduate medical education is delivered. One e-learning tool of note is the virtual patient (VP), a type of computer software that simulates real-life clinical scenarios, in which the learner emulates the role of health care provider to obtain the history, conduct examination, and make diagnoses and management decisions. VPs have been in use since 1993. Early designs were based on serial screen-cards of patient history, examination, investigations, diagnoses, treatment, and outcome, which the learner explored. With the development of web technology, VPs can now be accessed via the Internet and are more versatile, supporting different structural designs to suit a variety of learning objectives, and they can branch via different routes through a case. Using VPs has a number of advantages: 1) VPs improve access to learning material, 2) VPs help learners to acquire higher order cognitive skills like strategic thinking and decision making, 3) VPs provide a safe environment to practice, 4) VPs help to teach interdisciplinary care, and 5) VPs can be used instead of patients for examination. A number of well-known VP player systems are in use today: CASUS, CAMPUS, web-based Simulation of Patients, OpenLabyrinth, and vpSim. At the Chinese University of Hong Kong, we have also developed a web-based VP authoring and player system called Formative Assessment Case Studies (FACS), which is run by our Teaching and Learning Resources Centre. FACS has been integrated into Year-5 Anesthesia teaching since 2006. Three VP products have been developed: Anaesthesia FACS (six cases) that teaches preoperative assessment, Acute Pain Management FACS, and an eight-part longitudinal VP which tells the story of a patient’s stay, and anesthesia care, for routine gynecological surgery. Students spend about 3 hours on each during a 2-week clinical attachment. Our VPs have been well received and have overcome problems of providing adequate clinical exposure. PMID:23745078

Third-degree burn leading to partial foot amputation--why a notebook is no laptop.

PubMed

Paprottka, Felix Julian; Machens, Hans-Günther; Lohmeyer, Jörn Andreas

2012-08-01

So far a few case reports about laptops causing burns have been published. Now for the first time, we report on a case, in which notebook-induced thermal injuries placed in a patient's lap resulted in severe second- and third-degree burns. As a consequence, a partial amputation of the left foot had to be performed. Furthermore, we measured maximum temperatures of 12 popular laptops, which were running full load for 3 h. For this experiment air circulation underneath the device was blocked in order to simulate surrounding conditions, which were present when the patient got injured. Although this setting may be the reason for most of all notebook burns, this kind of test has not been part of any scientific publication until now. Patients with lower extremity sensation, altered consciousness or decreased peripheral sensitivity have a higher risk for thermal injuries. Copyright © 2012. Published by Elsevier Ltd.

MO-G-17A-07: Improved Image Quality in Brain F-18 FDG PET Using Penalized-Likelihood Image Reconstruction Via a Generalized Preconditioned Alternating Projection Algorithm: The First Patient Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidtlein, CR; Beattie, B; Humm, J

2014-06-15

Purpose: To investigate the performance of a new penalized-likelihood PET image reconstruction algorithm using the 1{sub 1}-norm total-variation (TV) sum of the 1st through 4th-order gradients as the penalty. Simulated and brain patient data sets were analyzed. Methods: This work represents an extension of the preconditioned alternating projection algorithm (PAPA) for emission-computed tomography. In this new generalized algorithm (GPAPA), the penalty term is expanded to allow multiple components, in this case the sum of the 1st to 4th order gradients, to reduce artificial piece-wise constant regions (“staircase” artifacts typical for TV) seen in PAPA images penalized with only the 1stmore » order gradient. Simulated data were used to test for “staircase” artifacts and to optimize the penalty hyper-parameter in the root-mean-squared error (RMSE) sense. Patient FDG brain scans were acquired on a GE D690 PET/CT (370 MBq at 1-hour post-injection for 10 minutes) in time-of-flight mode and in all cases were reconstructed using resolution recovery projectors. GPAPA images were compared PAPA and RMSE-optimally filtered OSEM (fully converged) in simulations and to clinical OSEM reconstructions (3 iterations, 32 subsets) with 2.6 mm XYGaussian and standard 3-point axial smoothing post-filters. Results: The results from the simulated data show a significant reduction in the 'staircase' artifact for GPAPA compared to PAPA and lower RMSE (up to 35%) compared to optimally filtered OSEM. A simple power-law relationship between the RMSE-optimal hyper-parameters and the noise equivalent counts (NEC) per voxel is revealed. Qualitatively, the patient images appear much sharper and with less noise than standard clinical images. The convergence rate is similar to OSEM. Conclusions: GPAPA reconstructions using the 1{sub 1}-norm total-variation sum of the 1st through 4th-order gradients as the penalty show great promise for the improvement of image quality over that currently achieved with clinical OSEM reconstructions.« less

Artificial intelligence framework for simulating clinical decision-making: a Markov decision process approach.

PubMed

Bennett, Casey C; Hauser, Kris

2013-01-01

In the modern healthcare system, rapidly expanding costs/complexity, the growing myriad of treatment options, and exploding information streams that often do not effectively reach the front lines hinder the ability to choose optimal treatment decisions over time. The goal in this paper is to develop a general purpose (non-disease-specific) computational/artificial intelligence (AI) framework to address these challenges. This framework serves two potential functions: (1) a simulation environment for exploring various healthcare policies, payment methodologies, etc., and (2) the basis for clinical artificial intelligence - an AI that can "think like a doctor". This approach combines Markov decision processes and dynamic decision networks to learn from clinical data and develop complex plans via simulation of alternative sequential decision paths while capturing the sometimes conflicting, sometimes synergistic interactions of various components in the healthcare system. It can operate in partially observable environments (in the case of missing observations or data) by maintaining belief states about patient health status and functions as an online agent that plans and re-plans as actions are performed and new observations are obtained. This framework was evaluated using real patient data from an electronic health record. The results demonstrate the feasibility of this approach; such an AI framework easily outperforms the current treatment-as-usual (TAU) case-rate/fee-for-service models of healthcare. The cost per unit of outcome change (CPUC) was $189 vs. $497 for AI vs. TAU (where lower is considered optimal) - while at the same time the AI approach could obtain a 30-35% increase in patient outcomes. Tweaking certain AI model parameters could further enhance this advantage, obtaining approximately 50% more improvement (outcome change) for roughly half the costs. Given careful design and problem formulation, an AI simulation framework can approximate optimal decisions even in complex and uncertain environments. Future work is described that outlines potential lines of research and integration of machine learning algorithms for personalized medicine. Copyright © 2012 Elsevier B.V. All rights reserved.

Introduction of Virtual Patient Software to Enhance Physician Assistant Student Knowledge in Palliative Medicine.

PubMed

Prazak, Kristine A

2017-01-01

The purpose of this project was to infuse palliative medicine and end-of-life care creatively into physician assistant (PA) education. Nine second-year PA students volunteered to participate in this quasi-experimental, pretest-posttest pilot study. Students initially completed an anonymous survey evaluating seven domains of knowledge in palliative medicine coupled with a self-assessment in competence. Virtual patient software was then used to simulate clinical encounters that addressed major palliative care domains. Upon completion of these cases, the same survey, with the addition of three questions about their own personal feelings, was administered. Overall response was positive in regard to improved knowledge and the virtual patient experience. After completion of the cases, students rated their self-assessed skills higher in all domains than prior to completing the cases. Factual knowledge scores showed a slight but not significant improvement, with an average pre-survey score of 4.56 and post-survey score of 4.67. Using virtual patient software can be a way of infusing palliative medicine and end-of-life care into PA education. These encounters can then be modified to include interprofessional encounters within the health professions.

Multiscale modeling and simulation of blood flow in coronary artery bypass graft surgeries

NASA Astrophysics Data System (ADS)

Sankaran, Sethuraman; Esmaily Moghadam, Mahdi; Kahn, Andy; Marsden, Alison

2011-11-01

We present a computational framework for modeling and simulation of blood flow in patients who undergo coronary artery bypass graft (CABG) surgeries. We evaluate the influence of shape on the homeostatic state, cardiac output, and other quantities of interest. We present a case study on a patient with multiple CABG. We build a patient-specific model of the blood vessels comprised of the aorta, vessels branching from the top of the aorta (brachiocephalic artery and carotids) and the coronary arteries, in addition to bypass grafts. The rest of the circulatory system is modeled using lumped parameter 0D models comprised of resistances, compliances, inertances and elastance. An algorithm is presented that computes these parameters automatically given constraints on the flow. A Finite element framework is used to compute blood flow and pressure in the 3D model to which the 0D code is coupled at the model inlets and outlets. An adaptive closed loop BC is used to capture the coupling of the various outlets of the model with inlets, and is compared with a model with fixed inlet BC. We compare and contrast the pressure, flowrate, coronary perfusion, and PV curves obtained in the different cases. Further, we compare and contrast quantities of interest such as wall shear stress, wall shear stress gradients and oscillatory shear index for different surgical geometries and discuss implications of patient-specific optimization. I would like to acknowlege AHA for funding this work.

Evaluation of a problem-specific SBAR tool to improve after-hours nurse-physician phone communication: a randomized trial.

PubMed

Joffe, Erel; Turley, James P; Hwang, Kevin O; Johnson, Todd R; Johnson, Craig W; Bernstam, Elmer V

2013-11-01

After-hours telephone communications are common in patient management. Patterns of communication of key information during after-hours phone calls were evaluated, and the utility of problem-specific Situation, Background, Assessment, Recommendation (SBAR) forms in improving this communication was assessed. In a randomized trial using a simulated on-call setting, 20 nurses called physicians regarding six cases adapted from inpatient records and based on the six most common reasons for after-hours nurse-physician communication. Three of the cases were handled without the SBAR forms (control cases), and three cases were handled with the forms (SBAR cases). Two cue types of communication were evaluated: situation cues, which conveyed the patient's situation (for example, a patient is confused), and background cues, which conveyed problem-specific data indicated on the SBAR forms (for example, the patient has a low sodium level). Ninety-two phone calls were analyzed (43 SBAR/49 controls). Most of the nurses reported the situation cues (SBAR 88%, control 84%, p = .60) but not the background cues. There was a trend toward fewer background cues communicated in the SBAR cases (14% versus 31%, p = .08). In 14% of the cases, on average, nurses omitted information or reported wrong information regarding the background cue. Physicians asked questions that resulted in the communication of the cues in a minority of the cases when the background cues were not originally provided by the nurses (SBAR 6%, control 16%, p = .39). In after-hours phone communication between physicians and nurses, significant information was often not communicated and physicians did not elicit the necessary information. Simply providing an SBAR-based form did not ensure complete communication of key information.

Online virtual cases to teach resource stewardship.

PubMed

Zhou, Linghong Linda; Tait, Gordon; Sandhu, Sharron; Steiman, Amanda; Lake, Shirley

2018-06-11

As health care costs rise, medical education must focus on high-value clinical decision making. To teach and assess efficient resource use in rheumatology, online virtual interactive cases (VICs) were developed to simulate real patient encounters to increase price transparency and reinforce cost consciousness. To teach and assess efficient resource use in rheumatology, online virtual interactive cases (VICs) were developed METHODS: The VIC modules were distributed to a sample of medical students and internal medicine residents, who were required to assess patients, order appropriate investigations, develop differential diagnoses and formulate management plans. Each action was associated with a time and price, with the totals compared against ideals. Trainees were evaluated not only on their diagnosis and patient management, but also on the total time, cost and value of their selected workup. Trainee responses were tracked anonymously, with opportunity to provide feedback at the end of each case. Seventeen medical trainees completed a total of 48 VIC modules. On average, trainees spent CAN $227.52 and 68 virtual minutes on each case, which was lower than expected. This may have been the result of a low management score of 52.4%, although on average 92.0% of participants in each case achieved the correct diagnosis. In addition, 85.7% felt more comfortable working up similar cases, and 57.1% believed that the modules increased their ability to appropriately order cost-conscious rheumatology investigations. Our initial assessment of the VIC rheumatology modules was positive, supporting their role as an effective tool in teaching an approach to rheumatology patients, with an emphasis on resource stewardship. Future directions include the expansion of cases, based on feedback, wider dissemination and an evaluation of learning retention. © 2018 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Non prescribed sale of antibiotics in Riyadh, Saudi Arabia: A Cross Sectional Study

PubMed Central

2011-01-01

Background Antibiotics sales without medical prescriptions are increasingly recognized as sources of antimicrobial misuse that can exacerbate the global burden of antibiotic resistance. We aimed to determine the percentage of pharmacies who sell antibiotics without medical prescriptions, examining the potential associated risks of such practice in Riyadh, Saudi Arabia, by simulation of different clinical scenarios. Methods A cross sectional study of a quasi-random sample of pharmacies stratified by the five regions of Riyadh. Each pharmacy was visited once by two investigators who simulated having a relative with a specific clinical illness (sore throat, acute bronchitis, otitis media, acute sinusitis, diarrhea, and urinary tract infection (UTI) in childbearing aged women). Results A total of 327 pharmacies were visited. Antibiotics were dispensed without a medical prescription in 244 (77.6%) of 327, of which 231 (95%) were dispensed without a patient request. Simulated cases of sore throat and diarrhea resulted in an antibiotic being dispensed in (90%) of encounters, followed by UTI (75%), acute bronchitis (73%), otitis media (51%) and acute sinusitis (40%). Metronidazole (89%) and ciprofloxacin (86%) were commonly given for diarrhea and UTI, respectively, whereas amoxicillin/clavulanate was dispensed (51%) for the other simulated cases. None of the pharmacists asked about antibiotic allergy history or provided information about drug interactions. Only 23% asked about pregnancy status when dispensing antibiotics for UTI-simulated cases. Conclusions We observed that an antibiotic could be obtained in Riyadh without a medical prescription or an evidence-based indication with associated potential clinical risks. Strict enforcement and adherence to existing regulations are warranted. PMID:21736711

Non prescribed sale of antibiotics in Riyadh, Saudi Arabia: a cross sectional study.

PubMed

Bin Abdulhak, Aref A; Altannir, Mohamad A; Almansor, Mohammed A; Almohaya, Mohammed S; Onazi, Atallah S; Marei, Mohammed A; Aldossary, Oweida F; Obeidat, Sadek A; Obeidat, Mustafa A; Riaz, Muhammad S; Tleyjeh, Imad M

2011-07-07

Antibiotics sales without medical prescriptions are increasingly recognized as sources of antimicrobial misuse that can exacerbate the global burden of antibiotic resistance. We aimed to determine the percentage of pharmacies who sell antibiotics without medical prescriptions, examining the potential associated risks of such practice in Riyadh, Saudi Arabia, by simulation of different clinical scenarios. A cross sectional study of a quasi-random sample of pharmacies stratified by the five regions of Riyadh. Each pharmacy was visited once by two investigators who simulated having a relative with a specific clinical illness (sore throat, acute bronchitis, otitis media, acute sinusitis, diarrhea, and urinary tract infection (UTI) in childbearing aged women). A total of 327 pharmacies were visited. Antibiotics were dispensed without a medical prescription in 244 (77.6%) of 327, of which 231 (95%) were dispensed without a patient request. Simulated cases of sore throat and diarrhea resulted in an antibiotic being dispensed in (90%) of encounters, followed by UTI (75%), acute bronchitis (73%), otitis media (51%) and acute sinusitis (40%). Metronidazole (89%) and ciprofloxacin (86%) were commonly given for diarrhea and UTI, respectively, whereas amoxicillin/clavulanate was dispensed (51%) for the other simulated cases. None of the pharmacists asked about antibiotic allergy history or provided information about drug interactions. Only 23% asked about pregnancy status when dispensing antibiotics for UTI-simulated cases. We observed that an antibiotic could be obtained in Riyadh without a medical prescription or an evidence-based indication with associated potential clinical risks. Strict enforcement and adherence to existing regulations are warranted.

Implementation and evaluation of a dilation and evacuation simulation training curriculum.

PubMed

York, Sloane L; McGaghie, William C; Kiley, Jessica; Hammond, Cassing

2016-06-01

To evaluate obstetrics and gynecology resident physicians' performance following a simulation curriculum on dilation and evacuation (D&E) procedures. This study included two phases: simulation curriculum development and resident physician performance evaluation following training on a D&E simulator. Trainees participated in two evaluations. Simulation training evaluated participants performing six cases on a D&E simulator, measuring procedural time and a 26-step checklist of D&E steps. The operative training portion evaluated residents' performance after training on the simulator using mastery learning techniques. Intra-operative evaluation was based on a 21-step checklist score, Objective Structured Assessment of Technical Skills (OSATS), and percentage of cases completed. Twenty-two residents participated in simulation training, demonstrating improved performance from cases one and two to cases five and six, as measured by checklist score and procedural time (p<.001 and p=.001, respectively). Of 10 participants in the operative training, all performed at least three D&Es, while seven performed at least six cases. While checklist scores did not change significantly from the first to sixth case (mean for first case: 18.3; for sixth case: 19.6; p=.593), OSATS ratings improved from case one (19.7) to case three (23.5; p=.001) and to case six (26.8; p=.005). Trainees completed approximately 71.6% of their first case (range: 21.4-100%). By case six, the six participants performed 81.2% of the case (range: 14.3-100%). D&E simulation using a newly-developed uterine model and simulation curriculum improves resident technical skills. Simulation training with mastery learning techniques transferred to high level of performance in OR using checklist. The OSATS measured skills and showed improvement in performance with subsequent cases. Implementation of a D&E simulation curriculum offers potential for improved surgical training and abortion provision. Copyright © 2016 Elsevier Inc. All rights reserved.

The application of the Practitioners in Applied Practice Model during breaking bad news communication training for medical students: a case study.

PubMed

Dunning, Rose; Laidlaw, Anita

2015-11-01

Breaking bad news is a key skill within clinical communication and one which can impact outcomes for both the patient and practitioner. The evidence base for effective clinical communication training in breaking bad news is scarce. Frameworks have been found to assist the practitioner, such as SPIKES; however, the pedagogical approach used alongside such frameworks can vary. This study sought to examine the impact of utilising the Practitioners in Applied Practice Model (PAPM) alongside the SPIKES framework for training undergraduate medical students in breaking bad news. A case study approach is used to highlight the impact of training based on the PAPM and SPIKES on patient-centred communication and simulated patient satisfaction with the clinical communication behaviour. Results showed that following training, both patient-centred behaviour and patient satisfaction improved. With detailed communication behaviour changes, a balance was established between rapport building behaviour, lifestyle and psychosocial talk alongside biomedical information. This case study shows how the PAPM could be utilised alongside the SPIKES framework to improve breaking bad news communication in medical undergraduate students and describes the behavioural basis of the improvement. Further research is required to show the generalisability of this training intervention. © The Author(s) 2015.

COMPUTATIONAL MITRAL VALVE EVALUATION AND POTENTIAL CLINICAL APPLICATIONS

PubMed Central

Chandran, Krishnan B.; Kim, Hyunggun

2014-01-01

The mitral valve (MV) apparatus consists of the two asymmetric leaflets, the saddle-shaped annulus, the chordae tendineae, and the papillary muscles. MV function over the cardiac cycle involves complex interaction between the MV apparatus components for efficient blood circulation. Common diseases of the MV include valvular stenosis, regurgitation, and prolapse. MV repair is the most popular and most reliable surgical treatment for early MV pathology. One of the unsolved problems in MV repair is to predict the optimal repair strategy for each patient. Although experimental studies have provided valuable information to improve repair techniques, computational simulations are increasingly playing an important role in understanding the complex MV dynamics, particularly with the availability of patient-specific real-time imaging modalities. This work presents a review of computational simulation studies of MV function employing finite element (FE) structural analysis and fluid-structure interaction (FSI) approach reported in the literature to date. More recent studies towards potential applications of computational simulation approaches in the assessment of valvular repair techniques and potential pre-surgical planning of repair strategies are also discussed. It is anticipated that further advancements in computational techniques combined with the next generations of clinical imaging modalities will enable physiologically more realistic simulations. Such advancement in imaging and computation will allow for patient-specific, disease-specific, and case-specific MV evaluation and virtual prediction of MV repair. PMID:25134487

Simulation as a Tool to Facilitate Practice Changes in Teams Taking Care of Patients Under Investigation for Ebola Virus Disease in Spain.

PubMed

Rojo, Elena; Oruña, Clara; Sierra, Dolores; García, Gema; Del Moral, Ignacio; Maestre, Jose M

2016-04-01

We analyzed the impact of simulation-based training on clinical practice and work processes on teams caring for patients with possible Ebola virus disease (EVD) in Cantabria, Spain. The Government of Spain set up a special committee for the management of EVD, and the Spanish Ministry of Health and foreign health services created an action protocol. Each region is responsible for selecting a reference hospital and an in-house care team to care for patients under investigation. Laboratory-confirmed cases of EVD have to be transferred to the Carlos III Health Institute in Madrid. Predeployment training and follow-up support are required to help personnel work safely and effectively. Simulation-based scenarios were designed to give staff the opportunity to practice before encountering a real-life situation. Lessons learned by each team during debriefings were listed, and a survey administered 3 months later assessed the implementation of practice and system changes. Implemented changes were related to clinical practice (eg, teamwork principles application), protocol implementation (eg, addition of new processes and rewriting of confusing parts), and system and workflow (eg, change of shift schedule and rearrangement of room equipment). Simulation can be used to detect needed changes in protocol or guidelines or can be adapted to meet the needs of a specific team.

Aneurysmal bone cyst: a hereditary disease?

PubMed

Leithner, Andreas; Machacek, Felix; Haas, Oskar A; Lang, Susanna; Ritschl, Peter; Radl, Roman; Windhager, Reinhard

2004-05-01

Recent genetic and immunohistochemical studies propose that the primary aneurysmal bone cyst is a tumour and not a reactive tumour-simulating lesion. Based on a familial case of aneurysmal bone cyst the authors contacted 135 patients with this disease. Sixty-eight females and 67 males (median age 14 years; range 2-73 years) were asked if other family members had bone lesions. One hundred and seven patients (79%) denied having other family members with lesions, 23 patients (17%) did not answer, and five patients (4%) gave evidence of other bone lesions in the family. These data indicate that a predisposing genetic defect could be part of a multifactorial pathogenesis in the development of some aneurysmal bone cysts.

Comparison of driving simulator performance and neuropsychological testing in narcolepsy.

PubMed

Kotterba, Sylvia; Mueller, Nicole; Leidag, Markus; Widdig, Walter; Rasche, Kurt; Malin, Jean-Pierre; Schultze-Werninghaus, Gerhard; Orth, Maritta

2004-09-01

Daytime sleepiness and cataplexy can increase automobile accident rates in narcolepsy. Several countries have produced guidelines for issuing a driving license. The aim of the study was to compare driving simulator performance and neuropsychological test results in narcolepsy in order to evaluate their predictive value regarding driving ability. Thirteen patients with narcolepsy (age: 41.5+/-12.9 years) and 10 healthy control patients (age: 55.1+/-7.8 years) were investigated. By computer-assisted neuropsychological testing, vigilance, alertness and divided attention were assessed. In a driving simulator patients and controls had to drive on a highway for 60 min (mean speed of 100 km/h). Different weather and daytime conditions and obstacles were presented. Epworth Sleepiness Scale-Scores were significantly raised (narcolepsy patients: 16.7+/-5.1, controls: 6.6+/-3.6, P < or = 0.001). The accident rate of the control patients increased (3.2+/-1.8 versus 1.3+/-1.5, P < or = 0.01). Significant differences in concentration lapses (e.g. tracking errors and deviation from speed limit) could not be revealed (9.8+/-3.5 versus 7.1+/-3.2, pns). Follow-up investigation in five patients after an optimising therapy could demonstrate the decrease in accidents due to concentration lapses (P < or = 0.05). Neuropsychological testing (expressed as percentage compared to a standardised control population) revealed deficits in alertness (32.3+/-28.6). Mean percentage scores of divided attention (56.9+/-25.4) and vigilance (58.7+/-26.8) were in a normal range. There was, however, a high inter-individual difference. There was no correlation between driving performance and neuropsychological test results or ESS Score. Neuropsychological test results did not significantly change in the follow-up. The difficulties encountered by the narcolepsy patient in remaining alert may account for sleep-related motor vehicle accidents. Driving simulator investigations are closely related to real traffic situations than isolated neuropsychological tests. At the present time the driving simulator seems to be a useful instrument judging driving ability especially in cases with ambiguous neuropsychological results.

Evaluating performance of risk identification methods through a large-scale simulation of observational data.

PubMed

Ryan, Patrick B; Schuemie, Martijn J

2013-10-01

There has been only limited evaluation of statistical methods for identifying safety risks of drug exposure in observational healthcare data. Simulations can support empirical evaluation, but have not been shown to adequately model the real-world phenomena that challenge observational analyses. To design and evaluate a probabilistic framework (OSIM2) for generating simulated observational healthcare data, and to use this data for evaluating the performance of methods in identifying associations between drug exposure and health outcomes of interest. Seven observational designs, including case-control, cohort, self-controlled case series, and self-controlled cohort design were applied to 399 drug-outcome scenarios in 6 simulated datasets with no effect and injected relative risks of 1.25, 1.5, 2, 4, and 10, respectively. Longitudinal data for 10 million simulated patients were generated using a model derived from an administrative claims database, with associated demographics, periods of drug exposure derived from pharmacy dispensings, and medical conditions derived from diagnoses on medical claims. Simulation validation was performed through descriptive comparison with real source data. Method performance was evaluated using Area Under ROC Curve (AUC), bias, and mean squared error. OSIM2 replicates prevalence and types of confounding observed in real claims data. When simulated data are injected with relative risks (RR) ≥ 2, all designs have good predictive accuracy (AUC > 0.90), but when RR < 2, no methods achieve 100 % predictions. Each method exhibits a different bias profile, which changes with the effect size. OSIM2 can support methodological research. Results from simulation suggest method operating characteristics are far from nominal properties.

A comparison between customized clear and removable orthodontic appliances manufactured using RP and CNC techniques.

PubMed

Martorelli, Massimo; Gerbino, Salvatore; Giudice, Michele; Ausiello, Pietro

2013-02-01

Aim of the research is to compare the orthodontic appliances fabricated by using rapid prototyping (RP) systems, in particular 3D printers, with those manufactured by using computer numerical control (CNC) milling machines. 3D printing is today a well-accepted technology to fabricate orthodontic aligners by using the thermoforming process, instead the potential of CNC systems in dentistry have not yet been sufficiently explored. One patient, with mal-positioned maxillary central and lateral incisors, was initially selected. In the computer aided virtual planning was defined that, for the treatment, the patient needed to wear a series of 7 removable orthodontic appliances (ROA) over a duration of 21 weeks, with one appliance for every 3 weeks. A non-contact reverse engineering (RE) structured-light 3D scanner was used to create the 3D STL model of the impression of the patient's mouth. Numerical FEM simulations were performed varying the position of applied forces (discrete and continuous forces) on the same model, simulating, in this way, 3 models with slice thickness of 0.2 mm, 0.1 mm (RP staircase effect) and without slicing (ideal case). To define the areas of application of forces, two configuration "i" and "i-1" of the treatment were overlapped. 6 patients to which for three steps (3rd, 4th and 5th step) were made to wear aligners fabricated starting from physical models by 3D printing (3DP-ROA) and afterwards, for the next steps (6th, 7th and 8th step), aligners fabricated starting from physical models by CNC milling machine (CNC-ROA), were selected. For the 6 patients wearing the CNC-ROA, it was observed a best fitting of the aligner to the teeth and a more rapid teeth movement than the 3DP-ROA (2 weeks compared to 3 weeks for every appliance). FEM simulations showed a more uniform stress distribution for CNC-ROA than 3DP-ROA. In this research, 6 different case studies and CAD-FEM simulations showed that, to fabricate an efficient clear and removable orthodontic aligner, it is necessary to consider a compromise of several factors. A lower staircase effect (lower layer thickness) and a higher physical prototype accuracy allow a better control of tooth movement. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Spiking Phineas Gage: a neurocomputational theory of cognitive-affective integration in decision making.

PubMed

Wagar, Brandon M; Thagard, Paul

2004-01-01

The authors present a neurological theory of how cognitive information and emotional information are integrated in the nucleus accumbens during effective decision making. They describe how the nucleus accumbens acts as a gateway to integrate cognitive information from the ventromedial prefrontal cortex and the hippocampus with emotional information from the amygdala. The authors have modeled this integration by a network of spiking artificial neurons organized into separate areas and used this computational model to simulate 2 kinds of cognitive-affective integration. The model simulates successful performance by people with normal cognitive-affective integration. The model also simulates the historical case of Phineas Gage as well as subsequent patients whose ability to make decisions became impeded by damage to the ventromedial prefrontal cortex.

SU-F-T-619: Dose Evaluation of Specific Patient Plans Based On Monte Carlo Algorithm for a CyberKnife Stereotactic Radiosurgery System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piao, J; PLA 302 Hospital, Beijing; Xu, S

2016-06-15

Purpose: This study will use Monte Carlo to simulate the Cyberknife system, and intend to develop the third-party tool to evaluate the dose verification of specific patient plans in TPS. Methods: By simulating the treatment head using the BEAMnrc and DOSXYZnrc software, the comparison between the calculated and measured data will be done to determine the beam parameters. The dose distribution calculated in the Raytracing, Monte Carlo algorithms of TPS (Multiplan Ver4.0.2) and in-house Monte Carlo simulation method for 30 patient plans, which included 10 head, lung and liver cases in each, were analyzed. The γ analysis with the combinedmore » 3mm/3% criteria would be introduced to quantitatively evaluate the difference of the accuracy between three algorithms. Results: More than 90% of the global error points were less than 2% for the comparison of the PDD and OAR curves after determining the mean energy and FWHM.The relative ideal Monte Carlo beam model had been established. Based on the quantitative evaluation of dose accuracy for three algorithms, the results of γ analysis shows that the passing rates (84.88±9.67% for head,98.83±1.05% for liver,98.26±1.87% for lung) of PTV in 30 plans between Monte Carlo simulation and TPS Monte Carlo algorithms were good. And the passing rates (95.93±3.12%,99.84±0.33% in each) of PTV in head and liver plans between Monte Carlo simulation and TPS Ray-tracing algorithms were also good. But the difference of DVHs in lung plans between Monte Carlo simulation and Ray-tracing algorithms was obvious, and the passing rate (51.263±38.964%) of γ criteria was not good. It is feasible that Monte Carlo simulation was used for verifying the dose distribution of patient plans. Conclusion: Monte Carlo simulation algorithm developed in the CyberKnife system of this study can be used as a reference tool for the third-party tool, which plays an important role in dose verification of patient plans. This work was supported in part by the grant from Chinese Natural Science Foundation (Grant No. 11275105). Thanks for the support from Accuray Corp.« less

The role of computer-aided 3D surgery and stereolithographic modelling for vector orientation in premaxillary and trans-sinusoidal maxillary distraction osteogenesis.

PubMed

Varol, Altan; Basa, Selçuk

2009-06-01

Maxillary distraction osteogenesis is a challenging procedure when it is performed with internal submerged distractors due to obligation of setting accurate distraction vectors. Five patients with severe maxillary retrognathy were planned with Mimics 10.01 CMF and Simplant 10.01 software. Distraction vectors and rods of distractors were arranged in 3D environment and on STL models. All patients were operated under general anaesthesia and complete Le Fort I downfracture was performed. All distractions were performed according to orientated vectors. All patients achieved stable occlusion and satisfactory aesthetic outcome at the end of the treatment period. Preoperative bending of internal maxillary distractors prevents significant loss of operation time. 3D computer-aided surgical simulation and model surgery provide accurate orientation of distraction vectors for premaxillary and internal trans-sinusoidal maxillary distraction. Combination of virtual surgical simulation and stereolithographic models surgery can be validated as an effective method of preoperative planning for complicated maxillofacial surgery cases.

Effectiveness of screening hospital admissions to detect asymptomatic carriers of Clostridium difficile: a modeling evaluation.

PubMed

Lanzas, Cristina; Dubberke, Erik R

2014-08-01

Both asymptomatic and symptomatic Clostridium difficile carriers contribute to new colonizations and infections within a hospital, but current control strategies focus only on preventing transmission from symptomatic carriers. Our objective was to evaluate the potential effectiveness of methods targeting asymptomatic carriers to control C. difficile colonization and infection (CDI) rates in a hospital ward: screening patients at admission to detect asymptomatic C. difficile carriers and placing positive patients into contact precautions. We developed an agent-based transmission model for C. difficile that incorporates screening and contact precautions for asymptomatic carriers in a hospital ward. We simulated scenarios that vary according to screening test characteristics, colonization prevalence, and type of strain present at admission. In our baseline scenario, on average, 42% of CDI cases were community-onset cases. Within the hospital-onset (HO) cases, approximately half were patients admitted as asymptomatic carriers who became symptomatic in the ward. On average, testing for asymptomatic carriers reduced the number of new colonizations and HO-CDI cases by 40%-50% and 10%-25%, respectively, compared with the baseline scenario. Test sensitivity, turnaround time, colonization prevalence at admission, and strain type had significant effects on testing efficacy. Testing for asymptomatic carriers at admission may reduce both the number of new colonizations and HO-CDI cases. Additional reductions could be achieved by preventing disease in patients who are admitted as asymptomatic carriers and developed CDI during the hospital stay.

[Osteoarticular coccidioidomicosis. Clinical and pathological study of 36 Mexican patients].

PubMed

Torres-Nájera, Manuel; de la Garza-Galván, Sergio; Cerda-Flores, Ricardo M; Nocedal-Rustrián, Fausto C; Calderón-Garcidueñas, Ana Laura

2006-01-01

Coccidioidomycosis (CM) is primarily a lung disease. Systemic spread occurs in 1% of cases and one of its manifestation is osteoarthritis. To describe the clinical and pathological characteristics of 36 patients with osteoarthritis by Coccidioides immitis (COA). The surgical pathology records of two medical institutions were reviewed; patients with clinical diagnosis of osteoarthritis and definitive histopathological diagnosis of COA were included in the study. Results were analyzed by contingence tables (RXC) and chi2 test. Twenty six adults (19 men, seven women) and 10 children (seven males, three females) were studied. The chi2 analysis demonstrated a predominance of disease in men (72.2%, p = 0.008). There was no difference between males and females in relation to history of mycotic disease or diagnosis of lung disease after the diagnosis of COA. Bone involvement (76% of cases) was more frequent that pure joint lesions and the predominant radiological lesion was of lytic type. 30.5% of patients (11 cases) had multiple bone lesions and eight of them were men with multiple vertebral bone lesions. The COA was the only manifestation of disease in 83% of the patients. Therefore is important to consider this etiology in patients of endemic area. The clinical and radiological spectrum of COA is wide and may include a dentigerous and synovial cyst or simulates metastatic disease. The recognition of the clinical manifestations of COA may contribute to an opportune diagnosis and treatment.

The case of "Miss Jacobs": adolescent simulated patients and the quality of their role playing, feedback, and personal impact.

PubMed

Bokken, Lonneke; van Dalen, Jan; Rethans, Jan-Joost

2010-12-01

Adolescents as standardized patients are relatively new in medical education. Studies have mostly explored the impact of role playing on adolescents trained to perform standardized patient roles for assessment purposes. No studies were found with regard to the quality of adolescents' role playing. We evaluated the effects of performing a patient role on adolescents trained as simulated patients (SPs) for teaching purposes (in contrast to standardized patients) and evaluated the quality of adolescent SPs' role playing and feedback. Nine young women, aged 16 to 18 years, were trained to portray roles of adolescents asking their general practitioner for an oral contraceptive. Three adolescent men were trained to portray roles of some of the girls' boyfriends. Each role was developed in consultation with the individual adolescent and was largely based on her own personal experience. Students rated the quality of the adolescent SP's role playing and feedback after each SP encounter on a previously validated questionnaire (the Maastricht Assessment of Simulated Patients). Both the adolescent SPs and faculty teachers both completed questionnaires on their experiences. Three hundred forty-one students rated the quality of the SPs' role playing and feedback with a mean score of 7.5 of 10. The faculty teachers were also generally positive about the role playing and feedback. Nevertheless, there were some concerns about the quality of the feedback. Adolescent SPs reported no negative effects because of their performance. Generally, students and teachers were satisfied with the quality of the role playing and feedback provided by the adolescent SPs. The adolescent SPs experienced no negative effects related to their performance, which confirms earlier findings among adolescent standardized patients.

Clinical applications of virtual navigation bronchial intervention.

PubMed

Kajiwara, Naohiro; Maehara, Sachio; Maeda, Junichi; Hagiwara, Masaru; Okano, Tetsuya; Kakihana, Masatoshi; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko

2018-01-01

In patients with bronchial tumors, we frequently consider endoscopic treatment as the first treatment of choice. All computed tomography (CT) must satisfy several conditions necessary to analyze images by Synapse Vincent. To select safer and more precise approaches for patients with bronchial tumors, we determined the indications and efficacy of virtual navigation intervention for the treatment of bronchial tumors. We examined the efficacy of virtual navigation bronchial intervention for the treatment of bronchial tumors located at a variety of sites in the tracheobronchial tree using a high-speed 3-dimensional (3D) image analysis system, Synapse Vincent. Constructed images can be utilized to decide on the simulation and interventional strategy as well as for navigation during interventional manipulation in two cases. Synapse Vincent was used to determine the optimal planning of virtual navigation bronchial intervention. Moreover, this system can detect tumor location and alsodepict surrounding tissues, quickly, accurately, and safely. The feasibility and safety of Synapse Vincent in performing useful preoperative simulation and navigation of surgical procedures can lead to safer, more precise, and less invasion for the patient, and makes it easy to construct an image, depending on the purpose, in 5-10 minutes using Synapse Vincent. Moreover, if the lesion is in the parenchyma or sub-bronchial lumen, it helps to perform simulation with virtual skeletal subtraction to estimate potential lesion movement. By using virtual navigation system for simulation, bronchial intervention was performed with no complications safely and precisely. Preoperative simulation using virtual navigation bronchial intervention reduces the surgeon's stress levels, particularly when highly skilled techniques are needed to operate on lesions. This task, including both preoperative simulation and intraoperative navigation, leads to greater safety and precision. These technological instruments are helpful for bronchial intervention procedures, and are also excellent devices for educational training.

Simulation and Feedback in Health Education: A Mixed Methods Study Comparing Three Simulation Modalities.

PubMed

Tait, Lauren; Lee, Kenneth; Rasiah, Rohan; Cooper, Joyce M; Ling, Tristan; Geelan, Benjamin; Bindoff, Ivan

2018-05-03

Background . There are numerous approaches to simulating a patient encounter in pharmacy education. However, little direct comparison between these approaches has been undertaken. Our objective was to investigate student experiences, satisfaction, and feedback preferences between three scenario simulation modalities (paper-, actor-, and computer-based). Methods . We conducted a mixed methods study with randomized cross-over of simulation modalities on final-year Australian graduate-entry Master of Pharmacy students. Participants completed case-based scenarios within each of three simulation modalities, with feedback provided at the completion of each scenario in a format corresponding to each simulation modality. A post-simulation questionnaire collected qualitative and quantitative responses pertaining to participant satisfaction, experiences, and feedback preferences. Results . Participants reported similar levels satisfaction across all three modalities. However, each modality resulted in unique positive and negative experiences, such as student disengagement with paper-based scenarios. Conclusion . Importantly, the themes of guidance and opportunity for peer discussion underlie the best forms of feedback for students. The provision of feedback following simulation should be carefully considered and delivered, with all three simulation modalities producing both positive and negative experiences in regard to their feedback format.

Computer tomography prototyping and virtual procedure simulation in difficult cases of hip replacement surgery.

PubMed

Parchi, Paolo Domenico; Ferrari, Vincenzo; Piolanti, Nicola; Andreani, Lorenzo; Condino, Sara; Evangelisti, Gisberto; Lisanti, Michele

2013-09-01

Each year approximately 1 million total hip replacements (THR) are performed worldwide. A percentage of failure due to surgical approach and imprecise implant placement still exists. These result in several serious complications. We propose an approach to plan, to simulate, and to assist prosthesis implantation for difficult cases of THR based on 3-D virtual models, generated by segmenting patients' CT images, 3-D solid models, obtained by rapid prototyping (RP), and virtual procedure simulation. We carried out 8 THR with the aid of 3-D reconstruction and RP. After each procedure a questionnaire was submitted to the surgeon to assess the perceived added value of the technology. In all cases, the surgeon evaluated the 3-D model as useful in order to perform the planning. The clinical results showed a mean increase in the Harris Hip Score of about 42.5 points. The mean time of prototyping was 7.3 hours, (min 3.5 hours, max 9.3 hours). The mean surgery time was 65 minutes (min 50 minutes, max 88 minutes). Our study suggests that meticulous preoperative planning is necessary in front of a great aberration of the joint and in absence of normal anatomical landmarks, CT scan is mandatory, and 3-D reconstruction with solid model is useful.

Molecular characterization, biofilm analysis and experimental biofouling study of Fusarium isolates from recent cases of fungal keratitis in New York State

PubMed Central

Dyavaiah, Madhu; Ramani, Rama; Chu, David S; Ritterband, David C; Shah, Mahendra K; Samsonoff, William A; Chaturvedi, Sudha; Chaturvedi, Vishnu

2007-01-01

Background To characterize Fusarium isolates from recent cases of fungal keratitis in contact lens wearers, and to investigate fungal association with MoistureLoc solution. Methods We studied six fungal isolates from recent cases of keratitis in New York State. The isolates were characterized by nucleotide sequencing and phylogenetic analyses of multiple genes, and then typed using minisatellite and microsatellite probes. Experimental fungal biofilm formation was tested by standard methods. MoistureLoc solutions were tested in biofouling studies for their efficacy in elimination of Fusarium contamination. Results Fusarium solani – corneal ulcers (2 isolates), lens case (1 isolate), and F. oxysporum – corneal ulcer (1 isolate), eye (1 isolate), were recovered from five patients. An opened bottle of MoistureLoc solution provided by a patient also yielded F. solani. Two distinct genotypes of F. solani as well as of F. oxysporum were present in the isolated strains. Remarkably, F. solani strains from the lens case and lens solution in one instance were similar, based on phylogenetic analyses and molecular typing. The solution isolate of F. solani formed biofilm on contact lenses in control conditions, but not when co-incubated with MoistureLoc solution. Both freshly opened and 3-month old MoistureLoc solutions effectively killed F. solani and F. oxysporum, when fungal contamination was simulated under recommended lens treatment regimen (4-hr). However, simulation of inappropriate use (15 – 60 min) led to the recovery of less than 1% of original inoculum of F. solani or F. oxysporum. Conclusion Temporary survival of F. solani and F. oxysporum in MoistureLoc suggested that improper lens cleaning regimen could be a possible contributing factor in recent infections. PMID:17263885

Virtual patients: development in cancer nursing education.

PubMed

Moule, Pam; Pollard, Katherine; Armoogum, Julie; Messer, Simon

2015-07-01

The number of men diagnosed with prostate cancer is increasing and internationally there are high incidence rates. It is important that nurses and healthcare professionals are enabled to provide appropriate care to those men affected by prostate cancer and their families. Despite this need, there is recognition that many professionals feel ill prepared and lack knowledge in a number of areas. This paper presents the development of a Virtual Patient (VP) online resource to support practitioner learning. To develop five online VP simulation scenarios to meet the learning needs of nurses and health-care professionals caring for men with prostate cancer. Topic areas for the VPs were taken from previous work exploring the needs of health care professionals working with men with prostate cancer. An initial scoping exercise involving nursing practitioners, students and a prostate cancer charity confirmed the focus of the case study scenarios. Service users and specialist practitioners reviewed an outline of each case study to ensure fidelity of the simulations scenarios. Cases were entered into UChoose, a web based interactive VP player and authoring tool. The final case studies were reviewed by a sample of both registered and non-registered nurses and nursing students. The majority of respondents reported an increase in knowledge and suggested that they would recommend the resource to others. A number of positive aspects of the resource were highlighted. Respondents also commented about areas of weakness, a number of which have been addressed subsequently. The VP case studies provided an opportunity to develop knowledge and confidence in caring for men with prostate cancer. The mode of delivery and the content was acceptable for less experienced and knowledgeable staff. Copyright © 2015 Elsevier Ltd. All rights reserved.

Linking Six Sigma to simulation: a new roadmap to improve the quality of patient care.

PubMed

Celano, Giovanni; Costa, Antonio; Fichera, Sergio; Tringali, Giuseppe

2012-01-01

Improving the quality of patient care is a challenge that calls for a multidisciplinary approach, embedding a broad spectrum of knowledge and involving healthcare professionals from diverse backgrounds. The purpose of this paper is to present an innovative approach that implements discrete-event simulation (DES) as a decision-supporting tool in the management of Six Sigma quality improvement projects. A roadmap is designed to assist quality practitioners and health care professionals in the design and successful implementation of simulation models within the define-measure-analyse-design-verify (DMADV) or define-measure-analyse-improve-control (DMAIC) Six Sigma procedures. A case regarding the reorganisation of the flow of emergency patients affected by vertigo symptoms was developed in a large town hospital as a preliminary test of the roadmap. The positive feedback from professionals carrying out the project looks promising and encourages further roadmap testing in other clinical settings. The roadmap is a structured procedure that people involved in quality improvement can implement to manage projects based on the analysis and comparison of alternative scenarios. The role of Six Sigma philosophy in improvement of the quality of healthcare services is recognised both by researchers and by quality practitioners; discrete-event simulation models are commonly used to improve the key performance measures of patient care delivery. The two approaches are seldom referenced and implemented together; however, they could be successfully integrated to carry out quality improvement programs. This paper proposes an innovative approach to bridge the gap and enrich the Six Sigma toolbox of quality improvement procedures with DES.

Impact of carotid stent cell design on vessel scaffolding: a case study comparing experimental investigation and numerical simulations.

PubMed

Conti, Michele; Van Loo, Denis; Auricchio, Ferdinando; De Beule, Matthieu; De Santis, Gianluca; Verhegghe, Benedict; Pirrelli, Stefano; Odero, Attilio

2011-06-01

To quantitatively evaluate the impact of carotid stent cell design on vessel scaffolding by using patient-specific finite element analysis of carotid artery stenting (CAS). The study was organized in 2 parts: (1) validation of a patient-specific finite element analysis of CAS and (2) evaluation of vessel scaffolding. Micro-computed tomography (CT) images of an open-cell stent deployed in a patient-specific silicone mock artery were compared with the corresponding finite element analysis results. This simulation was repeated for the closed-cell counterpart. In the second part, the stent strut distribution, as reflected by the inter-strut angles, was evaluated for both cell types in different vessel cross sections as a measure of scaffolding. The results of the patient-specific finite element analysis of CAS matched well with experimental stent deployment both qualitatively and quantitatively, demonstrating the reliability of the numerical approach. The measured inter-strut angles suggested that the closed-cell design provided superior vessel scaffolding compared to the open-cell counterpart. However, the full strut interconnection of the closed-cell design reduced the stent's ability to accommodate to the irregular eccentric profile of the vessel cross section, leading to a gap between the stent surface and the vessel wall. Even though this study was limited to a single stent design and one vascular anatomy, the study confirmed the capability of dedicated computer simulations to predict differences in scaffolding by open- and closed-cell carotid artery stents. These simulations have the potential to be used in the design of novel carotid stents or for procedure planning.

Interrater reliability of the Australasian Triage Scale for mental health patients.

PubMed

Creaton, Anne; Liew, Don; Knott, Jonathan; Wright, Melissa

2008-12-01

To evaluate interrater reliability of the Australasian Triage Scale (ATS) for mental health patients in ED. In a prospective descriptive study, triage nurses were shown video vignettes of simulated scenarios of mental health presentations. Trieurs (raters) were asked to allocate an ATS category (rating) to each case. The primary outcome was the degree of interrater reliability for each simulated case. Also assessed were differences between raters or settings, grouped by level of ED activity, state of origin, hospital type and familiarity with appropriate guidelines. Chi-squared analysis was used for independent categorical variables; the Friedman test was used to compare the triage scores between busy and quiet ED scenarios. Ordinal data results were compared using opartchi. All 90 eligible participants were enrolled. The highest interrater concordance was 65.6% whereas the lowest interrater concordance was 53.3%. Significant association occurred between the distribution of triage ratings, ED activity level and the state of origin. A busy ED resulted in the assignment of a more urgent ATS category and decrease in concordance. There is a need to develop and implement a validated, standardized national triage tool for mental health patients. The ATS per se is insufficient to ensure acceptable interrater reliability, particularly during busy periods in the ED, and between states. Given the influence the ATS has on key outcomes, it is imperative for this tool to be robust.

Exploring Learner Acceptance of the Use of Virtual Reality in Medical Education: A Case Study of Desktop and Projection-Based Display Systems

ERIC Educational Resources Information Center

Huang, Hsiu-Mei; Liaw, Shu-Sheng; Lai, Chung-Min

2016-01-01

Advanced technologies have been widely applied in medical education, including human-patient simulators, immersive virtual reality Cave Automatic Virtual Environment systems, and video conferencing. Evaluating learner acceptance of such virtual reality (VR) learning environments is a critical issue for ensuring that such technologies are used to…

Massive Air Embolism in a Fontan Patient

PubMed Central

Matte, Gregory S.; Kussman, Barry D.; Wagner, Joseph W.; Boyle, Sharon L.; Howe, Robert J.; Pigula, Frank A.; Emani, Sitaram M.

2011-01-01

Abstract: Most institutions performing cardiopulmonary bypass for congenital heart disease patients use an integrated hard shell cardiotomy and venous reservoir attached to an oxygenator. It is of paramount importance that the integrated reservoir be vented so as not to cause pressurization. A pressurized sealed cardiotomy has been reported to occur secondary to issues with vacuum assisted venous drainage systems as well as improper venting in general. We report a case of air embolus caused by retrograde propulsion of air through the venous line secondary to a pressurized cardiotomy reservoir in a patient with Fontan circulation. The mechanism of cardiotomy pressurization is described, and the scenario simulated in a mock circuit. PMID:21848177

Massive air embolism in a Fontan patient.

PubMed

Matte, Gregory S; Kussman, Barry D; Wagner, Joseph W; Boyle, Sharon L; Howe, Robert J; Pigula, Frank A; Emani, Sitaram M

2011-06-01

Most institutions performing cardiopulmonary bypass for congenital heart disease patients use an integrated hard shell cardiotomy and venous reservoir attached to an oxygenator. It is of paramount importance that the integrated reservoir be vented so as not to cause pressurization. A pressurized sealed cardiotomy has been reported to occur secondary to issues with vacuum assisted venous drainage systems as well as improper venting in general. We report a case of air embolus caused by retrograde propulsion of air through the venous line secondary to a pressurized cardiotomy reservoir in a patient with Fontan circulation. The mechanism of cardiotomy pressurization is described, and the scenario simulated in a mock circuit.

Verification of Dose Distribution in Carbon Ion Radiation Therapy for Stage I Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Irie, Daisuke; Saitoh, Jun-ichi, E-mail: junsaito@gunma-u.ac.jp; Shirai, Katsuyuki

Purpose: To evaluate robustness of dose distribution of carbon-ion radiation therapy (C-ion RT) in non-small cell lung cancer (NSCLC) and to identify factors affecting the dose distribution by simulated dose distribution. Methods and Materials: Eighty irradiation fields for delivery of C-ion RT were analyzed in 20 patients with stage I NSCLC. Computed tomography images were obtained twice before treatment initiation. Simulated dose distribution was reconstructed on computed tomography for confirmation under the same settings as actual treatment with respiratory gating and bony structure matching. Dose-volume histogram parameters, such as %D95 (percentage of D95 relative to the prescribed dose), were calculated.more » Patients with any field for which the %D95 of gross tumor volume (GTV) was below 90% were classified as unacceptable for treatment, and the optimal target margin for such cases was examined. Results: Five patients with a total of 8 fields (10% of total number of fields analyzed) were classified as unacceptable according to %D95 of GTV, although most patients showed no remarkable change in the dose-volume histogram parameters. Receiver operating characteristic curve analysis showed that tumor displacement and change in water-equivalent pathlength were significant predictive factors of unacceptable cases (P<.001 and P=.002, respectively). The main cause of degradation of the dose distribution was tumor displacement in 7 of the 8 unacceptable fields. A 6-mm planning target volume margin ensured a GTV %D95 of >90%, except in 1 extremely unacceptable field. Conclusions: According to this simulation analysis of C-ion RT for stage I NSCLC, a few fields were reported as unacceptable and required resetting of body position and reconfirmation. In addition, tumor displacement and change in water-equivalent pathlength (bone shift and/or chest wall thickness) were identified as factors influencing the robustness of dose distribution. Such uncertainties should be regarded in planning.« less

Patient-specific simulation of guidewire deformation during transcatheter aortic valve implantation.

PubMed

Vy, Phuoc; Auffret, Vincent; Castro, Miguel; Badel, Pierre; Rochette, Michel; Haigron, Pascal; Avril, Stéphane

2018-06-01

Transcatheter aortic valve implantation is a recent mini-invasive procedure to implant an aortic valve prosthesis. Prosthesis positioning in transcatheter aortic valve implantation appears as an important aspect for the success of the intervention. Accordingly, we developed a patient-specific finite element framework to predict the insertion of the stiff guidewire, used to position the aortic valve. We simulated the guidewire insertion for 2 patients based on their pre-operative CT scans. The model was designed to primarily predict the position and the angle of the guidewires in the aortic valve, and the results were successfully compared with intraoperative images. The present paper describes extensively the numerical model, which was solved by using the ANSYS software with an implicit resolution scheme, as well as the stabilization techniques which were used to overcome numerical instabilities. We performed sensitivity analysis on the properties of the guidewire (curvature angle, curvature radius, and stiffness) and the conditions of insertion (insertion force and orientation). We also explored the influence of the model parameters. The accuracy of the model was quantitatively evaluated as the distance and the angle difference between the simulated guidewires and the intraoperative ones. A good agreement was obtained between the model predictions and intraoperative views available for 2 patient cases. In conclusion, we showed that the shape of the guidewire in the aortic valve was mainly determined by the geometry of the patient's aorta and by the conditions of insertion (insertion force and orientation). Copyright © 2018 John Wiley & Sons, Ltd.

Air Force Operational Medicine: Using the Enterprise Estimating Supplies Program to Develop Materiel Solutions for the Operational Requirements of the Air Force Oral Surgery Team (FFMAX)

DTIC Science & Technology

2010-10-14

non-battle injuries , and illnesses. International Classification of Diseases, Ninth Revision (ICD-9) coded patient conditions that have been selected...The patient stream was used to simulate the equipment and supply requirements for the range of surgical cases and non-surgical injuries and illnesses...supplies” column identifies the items needed to complete the “Insert endo - trach tube” task at that level of capability. Not shown in this figure are

Investigation of ultra low-dose scans in the context of quantum-counting clinical CT

NASA Astrophysics Data System (ADS)

Weidinger, T.; Buzug, T. M.; Flohr, T.; Fung, G. S. K.; Kappler, S.; Stierstorfer, K.; Tsui, B. M. W.

2012-03-01

In clinical computed tomography (CT), images from patient examinations taken with conventional scanners exhibit noise characteristics governed by electronics noise, when scanning strongly attenuating obese patients or with an ultra-low X-ray dose. Unlike CT systems based on energy integrating detectors, a system with a quantum counting detector does not suffer from this drawback. Instead, the noise from the electronics mainly affects the spectral resolution of these detectors. Therefore, it does not contribute to the image noise in spectrally non-resolved CT images. This promises improved image quality due to image noise reduction in scans obtained from clinical CT examinations with lowest X-ray tube currents or obese patients. To quantify the benefits of quantum counting detectors in clinical CT we have carried out an extensive simulation study of the complete scanning and reconstruction process for both kinds of detectors. The simulation chain encompasses modeling of the X-ray source, beam attenuation in the patient, and calculation of the detector response. Moreover, in each case the subsequent image preprocessing and reconstruction is modeled as well. The simulation-based, theoretical evaluation is validated by experiments with a novel prototype quantum counting system and a Siemens Definition Flash scanner with a conventional energy integrating CT detector. We demonstrate and quantify the improvement from image noise reduction achievable with quantum counting techniques in CT examinations with ultra-low X-ray dose and strong attenuation.

Simple method to estimate mean heart dose from Hodgkin lymphoma radiation therapy according to simulation X-rays.

PubMed

van Nimwegen, Frederika A; Cutter, David J; Schaapveld, Michael; Rutten, Annemarieke; Kooijman, Karen; Krol, Augustinus D G; Janus, Cécile P M; Darby, Sarah C; van Leeuwen, Flora E; Aleman, Berthe M P

2015-05-01

To describe a new method to estimate the mean heart dose for Hodgkin lymphoma patients treated several decades ago, using delineation of the heart on radiation therapy simulation X-rays. Mean heart dose is an important predictor for late cardiovascular complications after Hodgkin lymphoma (HL) treatment. For patients treated before the era of computed tomography (CT)-based radiotherapy planning, retrospective estimation of radiation dose to the heart can be labor intensive. Patients for whom cardiac radiation doses had previously been estimated by reconstruction of individual treatments on representative CT data sets were selected at random from a case-control study of 5-year Hodgkin lymphoma survivors (n=289). For 42 patients, cardiac contours were outlined on each patient's simulation X-ray by 4 different raters, and the mean heart dose was estimated as the percentage of the cardiac contour within the radiation field multiplied by the prescribed mediastinal dose and divided by a correction factor obtained by comparison with individual CT-based dosimetry. According to the simulation X-ray method, the medians of the mean heart doses obtained from the cardiac contours outlined by the 4 raters were 30 Gy, 30 Gy, 31 Gy, and 31 Gy, respectively, following prescribed mediastinal doses of 25-42 Gy. The absolute-agreement intraclass correlation coefficient was 0.93 (95% confidence interval 0.85-0.97), indicating excellent agreement. Mean heart dose was 30.4 Gy with the simulation X-ray method, versus 30.2 Gy with the representative CT-based dosimetry, and the between-method absolute-agreement intraclass correlation coefficient was 0.87 (95% confidence interval 0.80-0.95), indicating good agreement between the two methods. Estimating mean heart dose from radiation therapy simulation X-rays is reproducible and fast, takes individual anatomy into account, and yields results comparable to the labor-intensive representative CT-based method. This simpler method may produce a meaningful measure of mean heart dose for use in studies of late cardiac complications. Copyright © 2015 Elsevier Inc. All rights reserved.

Virtual rehabilitation--benefits and challenges.

PubMed

Burdea, G C

2003-01-01

To discuss the advantages and disadvantages of rehabilitation applications of virtual reality. VR can be used as an enhancement to conventional therapy for patients with conditions ranging from musculoskeletal problems, to stroke-induced paralysis, to cognitive deficits. This approach is called "VR-augmented rehabilitation." Alternately, VR can replace conventional interventions altogether, in which case the rehabilitation is "VR-based." If the intervention is done at a distance, then it is called "telerehabilitation." Simulation exercises for post-stroke patients have been developed using a "teacher object" approach or a video game approach. Simulations for musculo-skeletal patients use virtual replicas of rehabilitation devices (such as rubber ball, power putty, peg board). Phobia-inducing virtual environments are prescribed for patients with cognitive deficits. VR-augmented rehabilitation has been shown effective for stroke patients in the chronic phase of the disease. VR-based rehabilitation has been improving patients with fear of flying, Vietnam syndrome, fear of heights, and chronic stroke patients. Telerehabilitation interventions using VR have improved musculo-skeletal and post-stroke patients, however less data is available at this time. Virtual reality presents significant advantages when applied to rehabilitation of patients with varied conditions. These advantages include patient motivation, adaptability and variability based on patient baseline, transparent data storage, online remote data access, economy of scale, reduced medical costs. Challenges in VR use for rehabilitation relate to lack of computer skills on the part of therapists, lack of support infrastructure, expensive equipment (initially), inadequate communication infrastructure (for telerehabilitation in rural areas), and patient safety concerns.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ureba, A.; Salguero, F. J.; Barbeiro, A. R.

Purpose: The authors present a hybrid direct multileaf collimator (MLC) aperture optimization model exclusively based on sequencing of patient imaging data to be implemented on a Monte Carlo treatment planning system (MC-TPS) to allow the explicit radiation transport simulation of advanced radiotherapy treatments with optimal results in efficient times for clinical practice. Methods: The planning system (called CARMEN) is a full MC-TPS, controlled through aMATLAB interface, which is based on the sequencing of a novel map, called “biophysical” map, which is generated from enhanced image data of patients to achieve a set of segments actually deliverable. In order to reducemore » the required computation time, the conventional fluence map has been replaced by the biophysical map which is sequenced to provide direct apertures that will later be weighted by means of an optimization algorithm based on linear programming. A ray-casting algorithm throughout the patient CT assembles information about the found structures, the mass thickness crossed, as well as PET values. Data are recorded to generate a biophysical map for each gantry angle. These maps are the input files for a home-made sequencer developed to take into account the interactions of photons and electrons with the MLC. For each linac (Axesse of Elekta and Primus of Siemens) and energy beam studied (6, 9, 12, 15 MeV and 6 MV), phase space files were simulated with the EGSnrc/BEAMnrc code. The dose calculation in patient was carried out with the BEAMDOSE code. This code is a modified version of EGSnrc/DOSXYZnrc able to calculate the beamlet dose in order to combine them with different weights during the optimization process. Results: Three complex radiotherapy treatments were selected to check the reliability of CARMEN in situations where the MC calculation can offer an added value: A head-and-neck case (Case I) with three targets delineated on PET/CT images and a demanding dose-escalation; a partial breast irradiation case (Case II) solved with photon and electron modulated beams (IMRT + MERT); and a prostatic bed case (Case III) with a pronounced concave-shaped PTV by using volumetric modulated arc therapy. In the three cases, the required target prescription doses and constraints on organs at risk were fulfilled in a short enough time to allow routine clinical implementation. The quality assurance protocol followed to check CARMEN system showed a high agreement with the experimental measurements. Conclusions: A Monte Carlo treatment planning model exclusively based on maps performed from patient imaging data has been presented. The sequencing of these maps allows obtaining deliverable apertures which are weighted for modulation under a linear programming formulation. The model is able to solve complex radiotherapy treatments with high accuracy in an efficient computation time.« less

A simulation of orientation dependent, global changes in camera sensitivity in ECT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bieszk, J.A.; Hawman, E.G.; Malmin, R.E.

1984-01-01

ECT promises the abilities to: 1) observe radioisotope distributions in a patient without the summation of overlying activity to reduce contrast, and 2) measure quantitatively these distributions to further and more accurately assess organ function. Ideally, camera-based ECT systems should have a performance that is independent of camera orientation or gantry angle. This study is concerned with ECT quantitation errors that can arise from angle-dependent variations of camera sensitivity. Using simulated phantoms representative of heart and liver sections, the effects of sensitivity changes on reconstructed images were assessed both visually and quantitatively based on ROI sums. The sinogram for eachmore » test image was simulated with 128 linear digitization and 180 angular views. The global orientation-dependent sensitivity was modelled by applying an angular sensitivity dependence to the sinograms of the test images. Four sensitivity variations were studied. Amplitudes of 0% (as a reference), 5%, 10%, and 25% with a costheta dependence were studied as well as a cos2theta dependence with a 5% amplitude. Simulations were done with and without Poisson noise to: 1) determine trends in the quantitative effects as a function of the magnitude of the variation, and 2) to see how these effects are manifested in studies having statistics comparable to clinical cases. For the most realistic sensitivity variation (costheta, 5% ampl.), the ROIs chosen in the present work indicated changes of <0.5% in the noiseless case and <5% for the case with Poisson noise. The effects of statistics appear to dominate any effects due to global, sinusoidal, orientation-dependent sensitivity changes in the cases studied.« less

The business case for quality improvement: oral anticoagulation for atrial fibrillation.

PubMed

Rose, Adam J; Berlowitz, Dan R; Ash, Arlene S; Ozonoff, Al; Hylek, Elaine M; Goldhaber-Fiebert, Jeremy D

2011-07-01

The potential to save money within a short time frame provides a more compelling "business case" for quality improvement than merely demonstrating cost-effectiveness. Our objective was to demonstrate the potential for cost savings from improved control in patients anticoagulated for atrial fibrillation. Our population consisted of 67 077 Veterans Health Administration patients anticoagulated for atrial fibrillation between October 1, 2006, and September 30, 2008. We simulated the number of adverse events and their associated costs and utilities, both before and after various degrees of improvement in percent time in therapeutic range (TTR). The simulation had a 2-year time horizon, and costs were calculated from the perspective of the payer. In the base-case analysis, improving TTR by 5% prevented 1114 adverse events, including 662 deaths; it gained 863 quality-adjusted life-years and saved $15.9 million compared with the status quo, not accounting for the cost of the quality improvement program. Improving TTR by 10% prevented 2087 events, gained 1606 quality-adjusted life-years, and saved $29.7 million. In sensitivity analyses, costs were most sensitive to the estimated risk of stroke and the expected stroke reduction from improved TTR. Utilities were most sensitive to the estimated risk of death and the expected mortality benefit from improved TTR. A quality improvement program to improve anticoagulation control probably would be cost-saving for the payer, even if it were only modestly effective in improving control and even without considering the value of improved health. This study demonstrates how to make a business case for a quality improvement initiative.

How does implant distribution affect 3D correction and bone-screw forces in thoracic adolescent idiopathic scoliosis spinal instrumentation?

PubMed

Le Navéaux, Franck; Larson, A Noelle; Labelle, Hubert; Wang, Xiaoyu; Aubin, Carl-Éric

2016-11-01

Optimal implant densities and configurations for thoracic spine instrumentation to treat adolescent idiopathic scoliosis remain unknown. The objective was to computationally assess the biomechanical effects of implant distribution on 3D curve correction and bone-implant forces. 3D patient-specific biomechanical spine models based on a multibody dynamic approach were created for 9 Lenke 1 patients who underwent posterior instrumentation (main thoracic Cobb: 43°-70°). For each case, a factorial design of experiments was used to generate 128 virtual implant configurations representative of existing implant patterns used in clinical practice. All instances except implant configuration were the same for each surgical scenario simulation. Simulation of the 128 implant configurations scenarios (mean implant density=1.32, range: 0.73-2) revealed differences of 2° to 10° in Cobb angle correction, 2° to 7° in thoracic kyphosis and 2° to 7° in apical vertebral rotation. The use of more implants, at the concave side only, was associated with higher Cobb angle correction (r=-0.41 to -0.90). Increased implant density was associated with higher apical vertebral rotation correction for seven cases (r=-0.20 to -0.48). It was also associated with higher bone-screw forces (r=0.22 to 0.64), with an average difference between the least and most constrained instrumentation constructs of 107N per implant at the end of simulated instrumentation. Low-density constructs, with implants mainly placed on the concave side, resulted in similar simulated curve correction as the higher-density patterns. Increasing the number of implants allows for only limited improvement of 3D correction and overconstrains the instrumentation construct, resulting in increased forces on the implants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of a Duplex Ultrasound Simulator and Preliminary Validation of Velocity Measurements in Carotid Artery Models.

PubMed

Zierler, R Eugene; Leotta, Daniel F; Sansom, Kurt; Aliseda, Alberto; Anderson, Mark D; Sheehan, Florence H

2016-07-01

Duplex ultrasound scanning with B-mode imaging and both color Doppler and Doppler spectral waveforms is relied upon for diagnosis of vascular pathology and selection of patients for further evaluation and treatment. In most duplex ultrasound applications, classification of disease severity is based primarily on alterations in blood flow velocities, particularly the peak systolic velocity (PSV) obtained from Doppler spectral waveforms. We developed a duplex ultrasound simulator for training and assessment of scanning skills. Duplex ultrasound cases were prepared from 2-dimensional (2D) images of normal and stenotic carotid arteries by reconstructing the common carotid, internal carotid, and external carotid arteries in 3 dimensions and computationally simulating blood flow velocity fields within the lumen. The simulator displays a 2D B-mode image corresponding to transducer position on a mannequin, overlaid by color coding of velocity data. A spectral waveform is generated according to examiner-defined settings (depth and size of the Doppler sample volume, beam steering, Doppler beam angle, and pulse repetition frequency or scale). The accuracy of the simulator was assessed by comparing the PSV measured from the spectral waveforms with the true PSV which was derived from the computational flow model based on the size and location of the sample volume within the artery. Three expert examiners made a total of 36 carotid artery PSV measurements based on the simulated cases. The PSV measured by the examiners deviated from true PSV by 8% ± 5% (N = 36). The deviation in PSV did not differ significantly between artery segments, normal and stenotic arteries, or examiners. To our knowledge, this is the first simulation of duplex ultrasound that can create and display real-time color Doppler images and Doppler spectral waveforms. The results demonstrate that an examiner can measure PSV from the spectral waveforms using the settings on the simulator with a mean absolute error in the velocity measurement of less than 10%. With the addition of cases with a range of pathologies, this duplex ultrasound simulator will be a useful tool for training health-care providers in vascular ultrasound applications and for assessing their skills in an objective and quantitative manner. © The Author(s) 2016.

Case management for at-risk elderly patients in the English integrated care pilots: observational study of staff and patient experience and secondary care utilisation

PubMed Central

Roland, Martin; Lewis, Richard; Steventon, Adam; Abel, Gary; Adams, John; Bardsley, Martin; Brereton, Laura; Chitnis, Xavier; Conklin, Annalijn; Staetsky, Laura; Tunkel, Sarah; Ling, Tom

2012-01-01

Introduction In 2009, the English Department of Health appointed 16 integrated care pilots which aimed to provide better integrated care. We report the quantitative results from a multi-method evaluation of six of the demonstration projects which used risk profiling tools to identify older people at risk of emergency hospital admission, combined with intensive case management for people identified as at risk. The interventions focused mainly on delivery system redesign and improved clinical information systems, two key elements of Wagner’s Chronic Care Model. Methods Questionnaires to staff and patients. Difference-in-differences analysis of secondary care utilisation using data on 3646 patients and 17,311 matched controls, and changes in overall secondary care utilisation. Results Most staff thought that care for their patients had improved. More patients reported having a care plan but they found it significantly harder to see a doctor or nurse of their choice and felt less involved in decisions about their care. Case management interventions were associated with a 9% increase in emergency admissions. We found some evidence of imbalance between cases and controls which could have biased this estimate, but simulations of the possible effect of unobserved confounders showed that it was very unlikely that the sites achieved their goal of reducing emergency admissions. However, we found significant reductions of 21% and 22% in elective admissions and outpatient attendance in the six months following an intervention, and overall inpatient and outpatient costs were significantly reduced by 9% during this period. Area level analyses of whole practice populations suggested that overall outpatient attendances were significantly reduced by 5% two years after the start of the case management schemes. Conclusion Case management may result in improvements in some aspects of care and has the potential to reduce secondary care costs. However, to improve patient experience, case management approaches need to be introduced in a way which respects patients’ wishes, for example the ability to see a familiar doctor or nurse. PMID:23593045

Development of an Experimental and Digital Cardiovascular Arterial Model for Transient Hemodynamic and Postural Change Studies: "A Preliminary Framework Analysis".

PubMed

Hewlin, Rodward L; Kizito, John P

2018-03-01

The ultimate goal of the present work is to aid in the development of tools to assist in the treatment of cardiovascular disease. Gaining an understanding of hemodynamic parameters for medical implants allow clinicians to have some patient-specific proposals for intervention planning. In the present work an experimental and digital computational fluid dynamics (CFD) arterial model consisting of a number of major arteries (aorta, carotid bifurcation, cranial, femoral, jejunal, and subclavian arteries) were fabricated to study: (1) the effects of local hemodynamics (flow parameters) on global hemodynamics (2) the effects of transition from bedrest to upright position (postural change) on hemodynamics, and (3) diffusion of dye (medical drug diffusion simulation) in the arterial system via experimental and numerical techniques. The experimental and digital arterial models used in the present study are the first 3-D systems reported in literature to incorporate the major arterial vessels that deliver blood from the heart to the cranial and femoral arteries. These models are also the first reported in literature to be used for flow parameter assessment via medical drug delivery and orthostatic postural change studies. The present work addresses the design of the experimental and digital arterial model in addition to the design of measuring tools used to measure hemodynamic parameters. The experimental and digital arterial model analyzed in the present study was developed from patient specific computed tomography angiography (CTA) scans and simplified geometric data. Segments such as the aorta (ascending and descending) and carotid bifurcation arteries of the experimental and digital arterial model was created from online available patient-specific CTA scan data provided by Charite' Clinical and Research Hospital. The cranial and coronary arteries were simplified arterial geometries developed from dimensional specification data used in previous work. For the patient specific geometries, a MATLAB code was written to upload the CTA scans of each artery, calculate the centroids, and produce surface splines at each discrete cross section along the lumen centerline to create the patient specific arterial geometries. The MATLAB code worked in conjunction with computer aided software (CAD) Solidworks to produce solid models of the patient specific geometries and united them with the simplified geometries to produce the full arterial model (CAD model). The CAD model was also used as a blueprint to fabricate the experimental model which was used for flow visualization via particle imaging velocimetry (PIV) and postural change studies. A custom pulse duplicator (pulsatile pump) was also designed and developed for the present work. The pulse duplicator is capable of producing patient-specific volumetric waveforms for inlet flow to the experimental arterial model. A simple fluid structure interaction (FSI) study was also conducted via optical techniques to establish the magnitude of vessel diameter change due to the pulsatile flow. A medical drug delivery (dye dispersion and tracing) case was simulated via a dye being dispersed into the pulsatile flow stream to measure the transit time of the dye front. Pressure waveforms for diseased cases (hypertension & stenotic cases) were also obtained from the experimental arterial model during postural changes from bedrest (0°) to upright position (90°). The postural changes were simulated via attaching the experimental model to a tile table the can transition from 0° to 90°. The PIV results obtained from the experimental model provided parametric data such as velocity and wall shear stress data. The medical drug delivery simulations (experimental and numerical) studies produce time dependent data which is useful for predicting flow trajectory and transit time of medical drug dispersion. In the case of postural change studies, pressure waveforms were obtained from the common carotid artery and the femoral sections to yield pressure difference data useful for orthostatic hypotension analysis. Flow parametric data such as vorticity (flow reversal), wall shear stress, normal stress, and medical drug transit data was also obtained from the digital arterial model CFD simulations. Although the present work is preliminary work, the experimental and digital models proves to be useful in providing flow parametric data of interest such as: (1) normal stress which is useful for predicting the magnitude of forces which could promote arterial rupture or dislodging of medical implants, (2) wall shear stress which is useful for analyzing the magnitude of drug transport at the arterial wall, (3) vorticity which is useful for predicting the magnitude of flow reversal, and (4) arterial compliance in the case of the experimental model which could be useful in the efforts of developing FSI numerical simulations that incorporates compliance which realistically models the flow in the arterial system.

'Simulation-based learning in psychiatry for undergraduates at the University of Zimbabwe medical school'.

PubMed

Piette, Angharad; Muchirahondo, Florence; Mangezi, Walter; Iversen, Amy; Cowan, Frances; Dube, Michelle; Peterkin, Hugh Grant-; Araya, Ricardo; Abas, Melanie

2015-02-21

The use of simulated patients to teach in psychiatry has not been reported from low-income countries. This is the first study using simulation teaching in psychiatry in Africa. The aim of this study was to introduce a novel method of psychiatric teaching to medical students at the University of Zimbabwe and assess its feasibility and preliminary effectiveness. We selected depression to simulate because students in Zimbabwe are most likely to see cases of psychoses during their ward-based clinical exposure. Zimbabwean psychiatrists adapted scenarios on depression and suicide based on ones used in London. Zimbabwean post-graduate trainee psychiatrists were invited to carry out the teaching and psychiatric nursing staff were recruited and trained in one hour to play the simulated patients (SPs). All students undertaking their psychiatry placement (n = 30) were allocated into groups for a short didactic lecture on assessing for clinical depression and then rotated around 3 scenarios in groups of 4-5 and asked to interview a simulated patient with signs of depression. Students received feedback from peers, SPs and facilitators. Students completed the Confidence in Assessing and Managing Depression (CAM-D) questionnaire before and after the simulation session and provided written free-text feedback. Post-graduate trainers, together with one consultant, facilitated the simulated teaching after three hours training. Student confidence scores increased from mean 15.90 to 20.05 (95% CI = 2.58- 5.71) t (20) = 5.52, (p > 0.0001) following the simulation teaching session. Free-text feedback was positive overall with students commenting that it was "helpful", "enjoyable" and "boosted confidence". In Zimbabwe, simulation teaching was acceptable and could be adapted with minimal effort by local psychiatrists and implemented by post-graduate trainees and one consultant, Students found it helpful and enjoyable and their confidence increased after the teaching. It offers students a broader exposure to psychiatric conditions than they receive during clinical attachment to the inpatient wards. Involving psychiatry trainees and nursing staff may be a sustainable approach in a setting with small number of consultants and limited funds to pay for professional actors.

Comparison of gatifloxacin and levofloxacin administered at various dosing regimens to hospitalised patients with community-acquired pneumonia: pharmacodynamic target attainment study using North American surveillance data for Streptococcus pneumoniae.

PubMed

Noreddin, Ayman M; Hoban, Daryl J; Zhanel, George G

2005-08-01

This work aimed at determining the target attainment potential of gatifloxacin and levofloxacin in specific age-related patient populations such as elderly (> or =65 years) versus younger (<65 years) hospitalised patients with community-acquired pneumonia (CAP). Previously described population pharmacokinetic models of gatifloxacin and levofloxacin administration in patients with serious CAP were utilised to simulate gatifloxacin and levofloxacin pharmacokinetics. Pharmacokinetic simulations and susceptibility data for Streptococcus pneumoniae from the ongoing national surveillance study, Canadian Respiratory Organism Susceptibility Study (CROSS), were then used to produce pharmacodynamic indices of free-drug area under the curve over 24h relative to the minimum inhibitory concentration (free-drug AUC(0-24)/MIC(all)). Monte Carlo simulations were then used to analyse target attainment both of gatifloxacin and levofloxacin to achieve free-drug AUC(0-24)/MIC(all)> or =30 against S. pneumoniae in patients with CAP. Dosing regimens for gatifloxacin were 400 mg once daily (qd) administered to younger patients (<65 years) and gatifloxacin 200 mg qd to elderly patients (> or =65 years). Dosing regimens for levofloxacin were simulated as 500 mg, 750 mg and 1000 mg qd administered to elderly patients as well as younger patients. Monte Carlo simulations using gatifloxacin 400mg against S. pneumoniae yielded probabilities of achieving free-drug AUC(0-24)/MIC(all) of 30 of 96.6% for all patients, 92.3% for younger patients and 97.7% for elderly patients. When administered to elderly patients, a reduced dose of gatifloxacin 200mg qd could achieve a target attainment potential of 91.4%. Monte Carlo simulation using levofloxacin 500 mg qd yielded probabilities of achieving free-drug AUC(0-24)/MIC(all) of 30 of 92.3% for all patients, 95.7% for elderly patients compared with 72.7% for younger patients. Using levofloxacin 750 mg and 1000 mg qd had probabilities of achieving free-drug AUC(0-24)/MIC(all) of 30 of 97.0% and 98.3%, 98.1% and 99.2%, and 90.1% and 95.2% for all patients, elderly patients and younger patients, respectively. The probability of achieving free-drug AUC(0-24)/MIC(all) of 100 was low both with gatifloxacin and levofloxacin, except in the case of elderly patients receiving levofloxacin in a dose of 1000 mg qd (78.5%). We conclude that gatifloxacin and levofloxacin pharmacokinetics in elderly patients with CAP are markedly different from those of younger patients. Higher gatifloxacin/levofloxacin AUC and longer half-life (t(1/2)) values in elderly patients with CAP compared with younger patients provide better pharmacodynamic parameters (free-drug AUC(0-24)/MIC) leading to a higher probability of pharmacodynamic target attainment and improved bacteriological outcome against S. pneumoniae. Gatifloxacin 400mg qd results in a high probability of target attainment and improved bacteriological outcome against S. pneumoniae both in young and elderly CAP patients. However, gatifloxacin administered at a lowered dose of 200 mg qd in elderly patients could still be successful in producing a favourable antibacterial effect. Levofloxacin administered at a dose of 750 mg qd results in a high probability of target attainment and improved bacteriological outcome against S. pneumoniae in all patients with CAP.

The effect of an educational intervention, based on clinical simulation, on the diagnosis of rheumatoid arthritis and osteoarthritis.

PubMed

Fernández-Ávila, Daniel G; Ruiz, Álvaro J; Gil, Fabián; Mora, Sergio A; Tobar, Carlos; Gutiérrez, Juan M; Rosselli, Diego

2018-03-01

The aim of the present study was to evaluate the effectiveness of an educational tool for general physicians, based on rheumatological clinical simulation, for the diagnosis of rheumatoid arthritis and osteoarthritis. A randomized clinical study was carried out, in which the physician research subjects were assigned to one of two groups: the experimental group (educational intervention for rheumatoid arthritis with clinical simulation) or the control group (educational intervention for the basic aspects of the diagnosis and treatment of osteoporosis). Four weeks after the educational intervention, the members of both groups completed an examination that included four clinical cases with real patients, two clinical cases with two clinical simulation models and six virtual clinical cases. In this examination, the participants noted clinical findings, established a diagnosis and defined the complementary tests they would request, if necessary, to corroborate their diagnosis. A total of 160 doctors participated (80 in the active educational intervention for rheumatoid arthritis and 80 in the control group), of whom 89 were women (56%). The mean age was 35 (standard deviation 7.7) years. Success was defined as a physician correctly diagnosing at least 10 of the 12 cases presented. A significant difference of 81.3% (95% confidence interval 72-90%; p < 0.001) in success was found in favour of the active group (88.8% versus 7.5%). A greater number of correct answers was found in the active group compared with the control group in the detection of clinical findings and in the number of complementary tests requested (p < 0.001). The study showed the effectiveness of an educational intervention based on clinical simulation to improve the diagnostic approach to rheumatoid arthritis and osteoarthritis. The results open a new horizon in the teaching of rheumatology. Copyright © 2017 John Wiley & Sons, Ltd.

Three-Dimensional Visualization with Large Data Sets: A Simulation of Spreading Cortical Depression in Human Brain

PubMed Central

Ertürk, Korhan Levent; Şengül, Gökhan

2012-01-01

We developed 3D simulation software of human organs/tissues; we developed a database to store the related data, a data management system to manage the created data, and a metadata system for the management of data. This approach provides two benefits: first of all the developed system does not require to keep the patient's/subject's medical images on the system, providing less memory usage. Besides the system also provides 3D simulation and modification options, which will help clinicians to use necessary tools for visualization and modification operations. The developed system is tested in a case study, in which a 3D human brain model is created and simulated from 2D MRI images of a human brain, and we extended the 3D model to include the spreading cortical depression (SCD) wave front, which is an electrical phoneme that is believed to cause the migraine. PMID:23258956

Visualization and simulated surgery of the left ventricle in the virtual pathological heart of the Virtual Physiological Human

PubMed Central

McFarlane, N. J. B.; Lin, X.; Zhao, Y.; Clapworthy, G. J.; Dong, F.; Redaelli, A.; Parodi, O.; Testi, D.

2011-01-01

Ischaemic heart failure remains a significant health and economic problem worldwide. This paper presents a user-friendly software system that will form a part of the virtual pathological heart of the Virtual Physiological Human (VPH2) project, currently being developed under the European Commission Virtual Physiological Human (VPH) programme. VPH2 is an integrated medicine project, which will create a suite of modelling, simulation and visualization tools for patient-specific prediction and planning in cases of post-ischaemic left ventricular dysfunction. The work presented here describes a three-dimensional interactive visualization for simulating left ventricle restoration surgery, comprising the operations of cutting, stitching and patching, and for simulating the elastic deformation of the ventricle to its post-operative shape. This will supply the quantitative measurements required for the post-operative prediction tools being developed in parallel in the same project. PMID:22670207

Simulated Conversations With Virtual Humans to Improve Patient-Provider Communication and Reduce Unnecessary Prescriptions for Antibiotics: A Repeated Measure Pilot Study.

PubMed

Schoenthaler, Antoinette; Albright, Glenn; Hibbard, Judith; Goldman, Ron

2017-04-19

Despite clear evidence that antibiotics do not cure viral infections, the problem of unnecessary prescribing of antibiotics in ambulatory care persists, and in some cases, prescribing patterns have increased. The overuse of antibiotics for treating viral infections has created numerous economic and clinical consequences including increased medical costs due to unnecessary hospitalizations, antibiotic resistance, disruption of gut bacteria, and obesity. Recent research has underscored the importance of collaborative patient-provider communication as a means to reduce the high rates of unnecessary prescriptions for antibiotics. However, most patients and providers do not feel prepared to engage in such challenging conversations. The aim of this pilot study was to assess the ability of a brief 15-min simulated role-play conversation with virtual humans to serve as a preliminary step to help health care providers and patients practice, and learn how to engage in effective conversations about antibiotics overuse. A total of 69 participants (35 providers and 34 patients) completed the simulation once in one sitting. A pre-post repeated measures design was used to assess changes in patients' and providers' self-reported communication behaviors, activation, and preparedness, intention, and confidence to effectively communicate in the patient-provider encounter. Changes in patients' knowledge and beliefs regarding antibiotic use were also evaluated. Patients experienced a short-term positive improvement in beliefs about appropriate antibiotic use for infection (F 1,30 =14.10, P=.001). Knowledge scores regarding the correct uses of antibiotics improved immediately postsimulation, but decreased at the 1-month follow-up (F 1,30 =31.16, P<.001). There was no change in patient activation and shared decision-making (SDM) scores in the total sample of patients (P>.10) Patients with lower levels of activation exhibited positive, short-term benefits in increased intent and confidence to discuss their needs and ask questions in the clinic visit, positive attitudes regarding participation in SDM with their provider, and accurate beliefs about the use of antibiotics (P<.10). The results also suggest small immediate gains in providers' attitudes about SDM (mean change 0.20; F 1,33 = 8.03, P=.01). This pilot study provided preliminary evidence on the efficacy of the use of simulated conversations with virtual humans as a tool to improve patient-provider communication (ie, through increasing patient confidence to actively participate in the visit and physician attitudes about SDM) for engaging in conversations about antibiotic use. Future research should explore if repeated opportunities to use the 15-min simulation as well as providing users with several different conversations to practice with would result in sustained improvements in antibiotics beliefs and knowledge and communication behaviors over time. The results of this pilot study offered several opportunities to improve on the simulation in order to bolster communication skills and knowledge retention. ©Antoinette Schoenthaler, Glenn Albright, Judith Hibbard, Ron Goldman. Originally published in JMIR Medical Education (http://mededu.jmir.org), 19.04.2017.

Incorporating Psychological Predictors of Treatment Response into Health Economic Simulation Models: A Case Study in Type 1 Diabetes.

PubMed

Kruger, Jen; Pollard, Daniel; Basarir, Hasan; Thokala, Praveen; Cooke, Debbie; Clark, Marie; Bond, Rod; Heller, Simon; Brennan, Alan

2015-10-01

. Health economic modeling has paid limited attention to the effects that patients' psychological characteristics have on the effectiveness of treatments. This case study tests 1) the feasibility of incorporating psychological prediction models of treatment response within an economic model of type 1 diabetes, 2) the potential value of providing treatment to a subgroup of patients, and 3) the cost-effectiveness of providing treatment to a subgroup of responders defined using 5 different algorithms. . Multiple linear regressions were used to investigate relationships between patients' psychological characteristics and treatment effectiveness. Two psychological prediction models were integrated with a patient-level simulation model of type 1 diabetes. Expected value of individualized care analysis was undertaken. Five different algorithms were used to provide treatment to a subgroup of predicted responders. A cost-effectiveness analysis compared using the algorithms to providing treatment to all patients. . The psychological prediction models had low predictive power for treatment effectiveness. Expected value of individualized care results suggested that targeting education at responders could be of value. The cost-effectiveness analysis suggested, for all 5 algorithms, that providing structured education to a subgroup of predicted responders would not be cost-effective. . The psychological prediction models tested did not have sufficient predictive power to make targeting treatment cost-effective. The psychological prediction models are simple linear models of psychological behavior. Collection of data on additional covariates could potentially increase statistical power. . By collecting data on psychological variables before an intervention, we can construct predictive models of treatment response to interventions. These predictive models can be incorporated into health economic models to investigate more complex service delivery and reimbursement strategies. © The Author(s) 2015.

Virtual reality lead extraction as a method for training new physicians: a pilot study.

PubMed

Maytin, Melanie; Daily, Thomas P; Carillo, Roger G

2015-03-01

It is estimated that the demand for transvenous lead extraction (TLE) has reached an annual extraction rate of nearly 24,000 patients worldwide. Despite technologic advances, TLE still has the potential for significant morbidity and mortality. Complication rates with TLE directly parallel operator experience. However, obtaining adequate training during and postfellowship can be difficult. Given the potential for catastrophic complications and the steep learning curve (up to 300 cases) associated with this procedure, we sought to validate a virtual reality (VR) lead extraction simulator as an innovative training and evaluation tool for physicians new to TLE. We randomized eight electrophysiology fellows to VR simulator versus conventional training. We compared procedural skill competency between the groups using simulator competency, tactile measurements, markers of proficiency and attitudes, and cognitive abilities battery. Practical skills and simulator complications differed significantly between the VR simulator and conventional training groups. The VR simulator group executed patient preparation and procedure performance better than the conventional group (P < 0.01). All four fellows randomized to conventional training experienced a simulator complication (two superior vena cava [SVC] tears, three right ventricle [RV] avulsions) versus one fellow in the VR simulator group (one SVC tear) (P = 0.02). Tactile measurements revealed a trend toward excess pushing versus pulling forces among the conventionally trained group. The time for lead removal was also significantly higher in the conventional training group (12.46 minutes vs 5.54 minutes, P = 0.02). There was no significant difference in baseline or posttraining cognitive ability. We contend that the implementation of alternative training tools such as a VR simulation model will improve physician training and allow for an innovative pathway to assess the achievement of competency. ©2014 Wiley Periodicals, Inc.

Hemodynamic Based Coronary Artery Aneurysm Thrombosis Risk Stratification in Kawasaki Disease Patients

NASA Astrophysics Data System (ADS)

Grande Gutierrez, Noelia; Mathew, M.; McCrindle, B.; Kahn, A.; Burns, J.; Marsden, A.

2017-11-01

Coronary artery aneurysms (CAA) as a result of Kawasaki Disease (KD) put patients at risk for thrombosis and myocardial infarction. Current AHA guidelines recommend CAA diameter >8 mm or Z-score >10 as the criterion for initiating systemic anticoagulation. Our hypothesis is that hemodynamic data derived from computational blood flow simulations is a better predictor of thrombosis than aneurysm diameter alone. Patient-specific coronary models were constructed from CMRI for a cohort of 10 KD patients (5 confirmed thrombosis cases) and simulations with fluid structure interaction were performed using the stabilized finite element Navier-Stokes solver available in SimVascular. We used a closed-loop lumped parameter network (LPN) to model the heart and vascular boundary conditions coupled numerically to the flow solver. An automated parameter estimation method was used to match LPN values to clinical data for each patient. Hemodynamic data analysis resulted in low correlation between Wall Shear Stress (WSS)/ Particle Residence Time (PRT) and CAA diameter but demonstrates the positive correlation between hemodynamics and adverse patient outcomes. Our results suggest that quantifying WSS and PRT should enable identification of regions at higher risk of thrombosis. We propose a quantitative method to non-invasively assess the abnormal flow in CAA following KD that could potentially improve clinical decision-making regarding anticoagulation therapy.

Bias correction of risk estimates in vaccine safety studies with rare adverse events using a self-controlled case series design.

PubMed

Zeng, Chan; Newcomer, Sophia R; Glanz, Jason M; Shoup, Jo Ann; Daley, Matthew F; Hambidge, Simon J; Xu, Stanley

2013-12-15

The self-controlled case series (SCCS) method is often used to examine the temporal association between vaccination and adverse events using only data from patients who experienced such events. Conditional Poisson regression models are used to estimate incidence rate ratios, and these models perform well with large or medium-sized case samples. However, in some vaccine safety studies, the adverse events studied are rare and the maximum likelihood estimates may be biased. Several bias correction methods have been examined in case-control studies using conditional logistic regression, but none of these methods have been evaluated in studies using the SCCS design. In this study, we used simulations to evaluate 2 bias correction approaches-the Firth penalized maximum likelihood method and Cordeiro and McCullagh's bias reduction after maximum likelihood estimation-with small sample sizes in studies using the SCCS design. The simulations showed that the bias under the SCCS design with a small number of cases can be large and is also sensitive to a short risk period. The Firth correction method provides finite and less biased estimates than the maximum likelihood method and Cordeiro and McCullagh's method. However, limitations still exist when the risk period in the SCCS design is short relative to the entire observation period.

Comparison of success of tracheal intubation using Macintosh laryngoscope-assisted Bonfils fiberscope and Truview video laryngoscope in simulated difficult airway

PubMed Central

Vivek, Bangaru; Sripriya, R.; Mishra, Gayatri; Ravishankar, M.; Parthasarathy, S.

2017-01-01

Background and Aims: Restriction of head and neck movements prevents the alignment of the oral, pharyngeal, and laryngeal axes and increases the incidence of difficult tracheal intubation in patients with cervical spine fractures. Video laryngoscopes have gained an important role in the management of difficult intubation, especially in situations with limited head and neck movements. This study compares the success of intubation using Macintosh laryngoscope assisted Bonfils® fiberscope (ML-BF) with TruviewPCD video laryngoscope (TV) in patients with simulated restricted head and neck movements. Material and Methods: One hundred and fifty-two patients satisfying the inclusion criteria were randomly allocated to two groups of 76 each. Patients were made to lie supine on the table without a pillow and a soft collar was used to restrict head and neck movements. After a standardized premedication-induction sequence, tracheal intubation was done either with ML-BF or TV. Success of intubation, time taken for successful intubation, hemodynamic changes, airway trauma, and postoperative oropharyngeal morbidity were noted. Results: Intubation was successful in all the 76 patients in direct laryngoscopy-Bonfils fiberscope group and 75 out of 76 patients in TV group within the specified time (90 s). The median time taken for successful intubation with TV and ML-BF were 44 (range 26–80) s and 49 (range 28–83) s, respectively. Hemodynamic changes, airway trauma, and postoperative oropharyngeal morbidity were similar in both groups. Conclusion: Both TV and ML-BF are equally effective for successful tracheal intubation in patients with simulated restricted head and neck movements. In cases of difficult laryngeal visualization with routine Macintosh laryngoscope, Bonfils can be used as an adjunct to achieve successful intubation in the same laryngoscopy attempt. PMID:28413282

The cost-benefit of federal investment in preventing Clostridium difficile infections through the use of a multifaceted infection control and antimicrobial stewardship program.

PubMed

Slayton, Rachel B; Scott, R Douglas; Baggs, James; Lessa, Fernanda C; McDonald, L Clifford; Jernigan, John A

2015-06-01

To determine the potential epidemiologic and economic value of the implementation of a multifaceted Clostridium difficile infection (CDI) control program at US acute care hospitals Markov model with a 5-year time horizon Patients whose data were used in our simulations were limited to hospitalized Medicare beneficiaries ≥65 years old. CDI is an important public health problem with substantial associated morbidity, mortality, and cost. Multifaceted national prevention efforts in the United Kingdom, including antimicrobial stewardship, patient isolation, hand hygiene, environmental cleaning and disinfection, and audit, resulted in a 59% reduction in CDI cases reported from 2008 to 2012. Our analysis was conducted from the federal perspective. The intervention we modeled included the following components: antimicrobial stewardship utilizing the Antimicrobial Use and Resistance module of the National Healthcare Safety Network (NHSN), use of contact precautions, and enhanced environmental cleaning. We parameterized our model using data from CDC surveillance systems, the AHRQ Healthcare Cost and Utilization Project, and literature reviews. To address uncertainty in our parameter estimates, we conducted sensitivity analyses for intervention effectiveness and cost, expenditures by other federal partners, and discount rate. Each simulation represented a cohort of 1,000 hospitalized patients over 1,000 trials. RESULTS In our base case scenario with 50% intervention effectiveness, we estimated that 509,000 CDI cases and 82,000 CDI-attributable deaths would be prevented over a 5-year time horizon. Nationally, the cost savings across all hospitalizations would be $2.5 billion (95% credible interval: $1.2 billion to $4.0 billion). The potential benefits of a multifaceted national CDI prevention program are sizeable from the federal perspective.

Accuracy and Radiation Dose Reduction of Limited-Range CT in the Evaluation of Acute Appendicitis in Pediatric Patients.

PubMed

Jin, Michael; Sanchez, Thomas R; Lamba, Ramit; Fananapazir, Ghaneh; Corwin, Michael T

2017-09-01

The purpose of this article is to determine the accuracy and radiation dose reduction of limited-range CT prescribed from the top of L2 to the top of the pubic symphysis in children with suspected acute appendicitis. We performed a retrospective study of 210 consecutive pediatric patients from December 11, 2012, through December 11, 2014, who underwent abdominopelvic CT for suspected acute appendicitis. Two radiologists independently reviewed the theoretic limited scans from the superior L2 vertebral body to the top of the pubic symphysis, to assess for visualization of the appendix, acute appendicitis, alternative diagnoses, and incidental findings. Separately, the same parameters were assessed on the full scan by the same two reviewers. Whole-body effective doses were determined for the full- and limited-range scans and were compared using the paired t test. The appendix or entire cecum was visualized on the limited scan in all cases, and no cases of acute appendicitis were missed on the simulated limited scan compared with the full scan. Two alternative diagnoses were missed with the limited scan: one case of hydronephrosis and one of acute acalculous cholecystitis. The mean effective dose for the original scan was 5.6 mSv and that for the simulated limited scan was 3.0 mSv, resulting in a dose reduction of 46.4% (p < 0.001). A limited-range CT examination performed from the top of L2 to the top of the pubic symphysis is as accurate as a full-range abdominopelvic CT in evaluating pediatric patients with suspected appendicitis and reduces the dose by approximately 46%.

Multivariable confounding adjustment in distributed data networks without sharing of patient-level data.

PubMed

Toh, Sengwee; Reichman, Marsha E; Houstoun, Monika; Ding, Xiao; Fireman, Bruce H; Gravel, Eric; Levenson, Mark; Li, Lingling; Moyneur, Erick; Shoaibi, Azadeh; Zornberg, Gwen; Hennessy, Sean

2013-11-01

It is increasingly necessary to analyze data from multiple sources when conducting public health safety surveillance or comparative effectiveness research. However, security, privacy, proprietary, and legal concerns often reduce data holders' willingness to share highly granular information. We describe and compare two approaches that do not require sharing of patient-level information to adjust for confounding in multi-site studies. We estimated the risks of angioedema associated with angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and aliskiren in comparison with beta-blockers within Mini-Sentinel, which has created a distributed data system of 18 health plans. To obtain the adjusted hazard ratios (HRs) and 95% confidence intervals (CIs), we performed (i) a propensity score-stratified case-centered logistic regression analysis, a method identical to a stratified Cox regression analysis but needing only aggregated risk set data, and (ii) an inverse variance-weighted meta-analysis, which requires only the site-specific HR and variance. We also performed simulations to further compare the two methods. Compared with beta-blockers, the adjusted HR was 3.04 (95% CI: 2.81, 3.27) for ACEIs, 1.16 (1.00, 1.34) for ARBs, and 2.85 (1.34, 6.04) for aliskiren in the case-centered analysis. The corresponding HRs were 2.98 (2.76, 3.21), 1.15 (1.00, 1.33), and 2.86 (1.35, 6.04) in the meta-analysis. Simulations suggested that the two methods may produce different results under certain analytic scenarios. The case-centered analysis and the meta-analysis produced similar results without the need to share patient-level data across sites in our empirical study, but may provide different results in other study settings. Copyright © 2013 John Wiley & Sons, Ltd.

Hydrodynamic and Longitudinal Impedance Analysis of Cerebrospinal Fluid Dynamics at the Craniovertebral Junction in Type I Chiari Malformation

PubMed Central

Martin, Bryn A.; Kalata, Wojciech; Shaffer, Nicholas; Fischer, Paul; Luciano, Mark; Loth, Francis

2013-01-01

Elevated or reduced velocity of cerebrospinal fluid (CSF) at the craniovertebral junction (CVJ) has been associated with type I Chiari malformation (CMI). Thus, quantification of hydrodynamic parameters that describe the CSF dynamics could help assess disease severity and surgical outcome. In this study, we describe the methodology to quantify CSF hydrodynamic parameters near the CVJ and upper cervical spine utilizing subject-specific computational fluid dynamics (CFD) simulations based on in vivo MRI measurements of flow and geometry. Hydrodynamic parameters were computed for a healthy subject and two CMI patients both pre- and post-decompression surgery to determine the differences between cases. For the first time, we present the methods to quantify longitudinal impedance (LI) to CSF motion, a subject-specific hydrodynamic parameter that may have value to help quantify the CSF flow blockage severity in CMI. In addition, the following hydrodynamic parameters were quantified for each case: maximum velocity in systole and diastole, Reynolds and Womersley number, and peak pressure drop during the CSF cardiac flow cycle. The following geometric parameters were quantified: cross-sectional area and hydraulic diameter of the spinal subarachnoid space (SAS). The mean values of the geometric parameters increased post-surgically for the CMI models, but remained smaller than the healthy volunteer. All hydrodynamic parameters, except pressure drop, decreased post-surgically for the CMI patients, but remained greater than in the healthy case. Peak pressure drop alterations were mixed. To our knowledge this study represents the first subject-specific CFD simulation of CMI decompression surgery and quantification of LI in the CSF space. Further study in a larger patient and control group is needed to determine if the presented geometric and/or hydrodynamic parameters are helpful for surgical planning. PMID:24130704

Approximate Bayesian algorithm to estimate the basic reproduction number in an influenza pandemic using arrival times of imported cases.

PubMed

Chong, Ka Chun; Zee, Benny Chung Ying; Wang, Maggie Haitian

2018-04-10

In an influenza pandemic, arrival times of cases are a proxy of the epidemic size and disease transmissibility. Because of intense surveillance of travelers from infected countries, detection is more rapid and complete than on local surveillance. Travel information can provide a more reliable estimation of transmission parameters. We developed an Approximate Bayesian Computation algorithm to estimate the basic reproduction number (R 0 ) in addition to the reporting rate and unobserved epidemic start time, utilizing travel, and routine surveillance data in an influenza pandemic. A simulation was conducted to assess the sampling uncertainty. The estimation approach was further applied to the 2009 influenza A/H1N1 pandemic in Mexico as a case study. In the simulations, we showed that the estimation approach was valid and reliable in different simulation settings. We also found estimates of R 0 and the reporting rate to be 1.37 (95% Credible Interval [CI]: 1.26-1.42) and 4.9% (95% CI: 0.1%-18%), respectively, in the 2009 influenza pandemic in Mexico, which were robust to variations in the fixed parameters. The estimated R 0 was consistent with that in the literature. This method is useful for officials to obtain reliable estimates of disease transmissibility for strategic planning. We suggest that improvements to the flow of reporting for confirmed cases among patients arriving at different countries are required. Copyright © 2018 Elsevier Ltd. All rights reserved.

SU-G-206-15: Effects of Dose Reduction On Emphysema Score

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, P; Wahi-Anwar, M; Kim, H

Purpose: The purpose of this study was to investigate the effects of reducing radiation dose levels on emphysema scores from lung cancer screening CT exams. Methods: 52 cases were selected from the National Lung Screening Trial (NLST) patients for which we had both the image series and the raw CT data. All scans were acquired with fixed effective mAs (25 for standard-sized patients, 40 for large patients) on a 64-slice scanner (Sensation 64, Siemens Healthcare) using 120kV, 64×0.6mm collimation and pitch 1.0. All images were reconstructed with 1mm slice thickness, B50 kernel. Based on a previously-published technique, we added noisemore » to the raw data to simulate reduced-dose versions at 50% and 25% of the original dose (approximately 1.0- and 0.5-mGy CTDIvol). Lung segmentations were obtained via region growing from manual seed point at a threshold of 600HU followed by manual removal of trachea and major airways. Lung segmentations were only performed on original dose scans, and mapped to simulated reduced-dose scans. Emphysema scores based on relative area of lung with attenuation values lower than −950HU (RA950) were computed for all cases. Results: Average RA950 of all 50 cases were 31.6 (±5.5), 32.5 (±4.9) and 32.8 (±4.6) for 100%, 50% and 25% dose level respectively. The average absolute difference in RA950 between simulated and original dose scans were 1.0 (±0.7) and 1.4 (±1.1) for 50% and 25% dose level respectively. Conclusion: RA950 is relatively robust to dose level, with a difference of no more than 5 from the original dose scans. The average RA950 of this population was high for a two reasons: This was a high risk population of patients with substantial smoking history; The use of B50 kernel, which may be biased towards high emphysema scores. Further exploration with smoother kernels will be conducted in the future. Institutional research agreement, Siemens Healthcare; Past recipient, research grant support, Siemens Healthcare; Consultant, Toshiba America Medical Systems; Consultant, Samsung Electronics; NIH grant support from U01 CA181156.« less

Varix of the vortex vein ampulla simulating choroidal melanoma: report of four cases.

PubMed

Gündüz, K; Shields, C L; Shields, J A

1998-01-01

Varix of the vortex vein ampulla is a condition that can cause diagnostic confusion with choroidal melanoma. A case series review was performed from the Ocular Oncology Service, Wills Eye Hospital. In all four cases, the patients were referred with the diagnosis of a small choroidal melanoma. The lesions were located in the nasal quadrant of the fundus near the equator. One patient had two lesions in the same quadrant. In all cases, the fundus lesion became more prominent when the eye gazed in the direction of the lesion and diminished in primary gaze. The mass measured up to 6.0 mm in base diameter and 2.5 mm in thickness in proper gaze. B-scan ultrasonography showed acoustic solidity and gaze-evoked dynamic enlargement of the lesion. Indocyanine green angiography demonstrated early pooling of dye and gaze-evoked fluctuation of the hyperfluorescence in the lesion. Color Doppler imaging, performed in one patient, showed a vascular lesion of venous origin that filled when the eye was placed in the direction of the lesion. Varix of the vortex vein is a condition that should be considered in the differential diagnosis of equatorial small choroidal melanoma. The dynamic nature of the lesion is characteristic and diagnostic.

Interprofessional collaboration between residents and nurses in general internal medicine: a qualitative study on behaviours enhancing teamwork quality.

PubMed

Muller-Juge, Virginie; Cullati, Stéphane; Blondon, Katherine S; Hudelson, Patricia; Maître, Fabienne; Vu, Nu V; Savoldelli, Georges L; Nendaz, Mathieu R

2014-01-01

Effective teamwork is necessary for optimal patient care. There is insufficient understanding of interactions between physicians and nurses on internal medicine wards. To describe resident physicians' and nurses' actual behaviours contributing to teamwork quality in the setting of a simulated internal medicine ward. A volunteer sample of 14 pairs of residents and nurses in internal medicine was asked to manage one non-urgent and one urgent clinical case in a simulated ward, using a high-fidelity manikin. After the simulation, participants attended a stimulated-recall session during which they viewed the videotape of the simulation and explained their actions and perceptions. All simulations were transcribed, coded, and analyzed, using a qualitative method (template analysis). Quality of teamwork was assessed, based on patient management efficiency and presence of shared management goals and of team spirit. Most resident-nurse pairs tended to interact in a traditional way, with residents taking the leadership and nurses executing medical prescriptions and assuming their own specific role. They also demonstrated different types of interactions involving shared responsibilities and decision making, constructive suggestions, active communication and listening, and manifestations of positive team building. The presence of a leader in the pair or a truly shared leadership between resident and nurse contributed to teamwork quality only if both members of the pair demonstrated sufficient autonomy. In case of a lack of autonomy of one member, the other member could compensate for it, if his/her own autonomy was sufficiently strong and if there were demonstrations of mutual listening, information sharing, and positive team building. Although they often relied on traditional types of interaction, residents and nurses also demonstrated readiness for increased sharing of responsibilities. Interprofessional education should insist on better redefinition of respective roles and reinforce behaviours shown to enhance teamwork quality.

Interprofessional Collaboration between Residents and Nurses in General Internal Medicine: A Qualitative Study on Behaviours Enhancing Teamwork Quality

PubMed Central

Muller-Juge, Virginie; Cullati, Stéphane; Blondon, Katherine S.; Hudelson, Patricia; Maître, Fabienne; Vu, Nu V.; Savoldelli, Georges L.; Nendaz, Mathieu R.

2014-01-01

Background Effective teamwork is necessary for optimal patient care. There is insufficient understanding of interactions between physicians and nurses on internal medicine wards. Objective To describe resident physicians’ and nurses’ actual behaviours contributing to teamwork quality in the setting of a simulated internal medicine ward. Methods A volunteer sample of 14 pairs of residents and nurses in internal medicine was asked to manage one non-urgent and one urgent clinical case in a simulated ward, using a high-fidelity manikin. After the simulation, participants attended a stimulated-recall session during which they viewed the videotape of the simulation and explained their actions and perceptions. All simulations were transcribed, coded, and analyzed, using a qualitative method (template analysis). Quality of teamwork was assessed, based on patient management efficiency and presence of shared management goals and of team spirit. Results Most resident-nurse pairs tended to interact in a traditional way, with residents taking the leadership and nurses executing medical prescriptions and assuming their own specific role. They also demonstrated different types of interactions involving shared responsibilities and decision making, constructive suggestions, active communication and listening, and manifestations of positive team building. The presence of a leader in the pair or a truly shared leadership between resident and nurse contributed to teamwork quality only if both members of the pair demonstrated sufficient autonomy. In case of a lack of autonomy of one member, the other member could compensate for it, if his/her own autonomy was sufficiently strong and if there were demonstrations of mutual listening, information sharing, and positive team building. Conclusions Although they often relied on traditional types of interaction, residents and nurses also demonstrated readiness for increased sharing of responsibilities. Interprofessional education should insist on better redefinition of respective roles and reinforce behaviours shown to enhance teamwork quality. PMID:24769672

Thoracoscopic anatomical lung segmentectomy using 3D computed tomography simulation without tumour markings for non-palpable and non-visualized small lung nodules.

PubMed

Kato, Hirohisa; Oizumi, Hiroyuki; Suzuki, Jun; Hamada, Akira; Watarai, Hikaru; Sadahiro, Mitsuaki

2017-09-01

Although wedge resection can be curative for small lung tumours, tumour marking is sometimes required for resection of non-palpable or visually undetectable lung nodules as a method for identification of tumours. Tumour marking sometimes fails and occasionally causes serious complications. We have performed many thoracoscopic segmentectomies using 3D computed tomography simulation for undetectable small lung tumours without any tumour markings. The aim of this study was to investigate whether thoracoscopic segmentectomy planned with 3D computed tomography simulation could precisely remove non-palpable and visually undetectable tumours. Between January 2012 and March 2016, 58 patients underwent thoracoscopic segmentectomy using 3D computed tomography simulation for non-palpable, visually undetectable tumours. Surgical outcomes were evaluated. A total of 35, 14 and 9 patients underwent segmentectomy, subsegmentectomy and segmentectomy combined with adjacent subsegmentectomy, respectively. All tumours were correctly resected without tumour marking. The median tumour size and distance from the visceral pleura was 14 ± 5.2 mm (range 5-27 mm) and 11.6 mm (range 1-38.8 mm), respectively. Median values related to the procedures were operative time, 176 min (range 83-370 min); blood loss, 43 ml (range 0-419 ml); duration of chest tube placement, 1 day (range 1-8 days); and postoperative hospital stay, 5 days (range 3-12 days). Two cases were converted to open thoracotomy due to bleeding. Three cases required pleurodesis for pleural fistula. No recurrences occurred during the mean follow-up period of 44.4 months (range 5-53 months). Thoracoscopic segmentectomy using 3D computed tomography simulation was feasible and could be performed to resect undetectable tumours with no tumour markings. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Social context modulates cognitive markers in Obsessive-Compulsive Disorder.

PubMed

Santamaría-García, Hernando; Soriano-Mas, Carles; Burgaleta, Miguel; Ayneto, Alba; Alonso, Pino; Menchón, José M; Cardoner, Narcis; Sebastián-Gallés, Nuria

2017-08-03

Error monitoring, cognitive control and motor inhibition control are proposed as cognitive alterations disrupted in obsessive-compulsive disorder (OCD). OCD has also been associated with an increased sensitivity to social evaluations. The effect of a social simulation over electrophysiological indices of cognitive alterations in OCD was examined. A case-control cross-sectional study measuring event-related potentials (ERP) for error monitoring (Error-Related Negativity), cognitive control (N2) and motor control (LRP) was conducted. We analyzed twenty OCD patients and twenty control participants. ERP were recorded during a social game consisting of a visual discrimination task, which was performed in the presence of a simulated superior or an inferior player. Significant social effects (different ERP amplitudes in Superior vs. Inferior player conditions) were found for OCD patients, but not for controls, in all ERP components. Performing the task against a simulated inferior player reduced abnormal ERP responses in OCD to levels observed in controls. The hierarchy-induced ERP effects were accompanied effects over reaction times in OCD patients. Social context modulates signatures of abnormal cognitive functioning in OCD, therefore experiencing a social superiority position impacts over cognitive processes in OCD such as error monitoring mechanisms. These results open the door for the research of new therapeutic choices.

Development, implementation and initial evaluation of narrative virtual patients for use in vocational mental health nurse training.

PubMed

Guise, Veslemøy; Chambers, Mary; Conradi, Emily; Kavia, Sheetal; Välimäki, Maritta

2012-08-01

Simulation techniques such as virtual patients (VPs) are valuable tools for teaching and learning a range of clinical proficiencies. Compared with other forms of simulation, however, the reported use of VPs within nursing is limited. Descriptions of simple, low cost methods for the development of VP devices could help facilitate their wider implementation and use in nursing education and training. In order to encourage broader use of VP technologies within nursing, this paper aims to expand current knowledge of VP creation by reference to the development of two virtual mental health patients produced for a multilingual e-learning course for European mental health nurses. Focusing on narrative VPs, the paper provides a brief overview of various types and potential uses of VP techniques, along with central elements of good practice in VP development. The five phase development framework used in the creation of the two VPs is presented. Processes detailed include the design and construction of case scenarios and multimedia components, in addition to initial usability and validity testing. VPs like those described here are a relatively inexpensive way of integrating virtual simulation technology into nursing education, particularly within online, blended and/or cross-cultural learning environments. Copyright © 2011 Elsevier Ltd. All rights reserved.

Towards personalised management of atherosclerosis via computational models in vascular clinics: technology based on patient-specific simulation approach

PubMed Central

Di Tomaso, Giulia; Agu, Obiekezie; Pichardo-Almarza, Cesar

2014-01-01

The development of a new technology based on patient-specific modelling for personalised healthcare in the case of atherosclerosis is presented. Atherosclerosis is the main cause of death in the world and it has become a burden on clinical services as it manifests itself in many diverse forms, such as coronary artery disease, cerebrovascular disease/stroke and peripheral arterial disease. It is also a multifactorial, chronic and systemic process that lasts for a lifetime, putting enormous financial and clinical pressure on national health systems. In this Letter, the postulate is that the development of new technologies for healthcare using computer simulations can, in the future, be developed as in-silico management and support systems. These new technologies will be based on predictive models (including the integration of observations, theories and predictions across a range of temporal and spatial scales, scientific disciplines, key risk factors and anatomical sub-systems) combined with digital patient data and visualisation tools. Although the problem is extremely complex, a simulation workflow and an exemplar application of this type of technology for clinical use is presented, which is currently being developed by a multidisciplinary team following the requirements and constraints of the Vascular Service Unit at the University College Hospital, London. PMID:26609369

A comparison of estimators from self-controlled case series, case-crossover design, and sequence symmetry analysis for pharmacoepidemiological studies.

PubMed

Takeuchi, Yoshinori; Shinozaki, Tomohiro; Matsuyama, Yutaka

2018-01-08

Despite the frequent use of self-controlled methods in pharmacoepidemiological studies, the factors that may bias the estimates from these methods have not been adequately compared in real-world settings. Here, we comparatively examined the impact of a time-varying confounder and its interactions with time-invariant confounders, time trends in exposures and events, restrictions, and misspecification of risk period durations on the estimators from three self-controlled methods. This study analyzed self-controlled case series (SCCS), case-crossover (CCO) design, and sequence symmetry analysis (SSA) using simulated and actual electronic medical records datasets. We evaluated the performance of the three self-controlled methods in simulated cohorts for the following scenarios: 1) time-invariant confounding with interactions between the confounders, 2) time-invariant and time-varying confounding without interactions, 3) time-invariant and time-varying confounding with interactions among the confounders, 4) time trends in exposures and events, 5) restricted follow-up time based on event occurrence, and 6) patient restriction based on event history. The sensitivity of the estimators to misspecified risk period durations was also evaluated. As a case study, we applied these methods to evaluate the risk of macrolides on liver injury using electronic medical records. In the simulation analysis, time-varying confounding produced bias in the SCCS and CCO design estimates, which aggravated in the presence of interactions between the time-invariant and time-varying confounders. The SCCS estimates were biased by time trends in both exposures and events. Erroneously short risk periods introduced bias to the CCO design estimate, whereas erroneously long risk periods introduced bias to the estimates of all three methods. Restricting the follow-up time led to severe bias in the SSA estimates. The SCCS estimates were sensitive to patient restriction. The case study showed that although macrolide use was significantly associated with increased liver injury occurrence in all methods, the value of the estimates varied. The estimations of the three self-controlled methods depended on various underlying assumptions, and the violation of these assumptions may cause non-negligible bias in the resulting estimates. Pharmacoepidemiologists should select the appropriate self-controlled method based on how well the relevant key assumptions are satisfied with respect to the available data.

Parameter estimation of brain tumors using intraoperative thermal imaging based on artificial tactile sensing in conjunction with artificial neural network

NASA Astrophysics Data System (ADS)

Sadeghi-Goughari, M.; Mojra, A.; Sadeghi, S.

2016-02-01

Intraoperative Thermal Imaging (ITI) is a new minimally invasive diagnosis technique that can potentially locate margins of brain tumor in order to achieve maximum tumor resection with least morbidity. This study introduces a new approach to ITI based on artificial tactile sensing (ATS) technology in conjunction with artificial neural networks (ANN) and feasibility and applicability of this method in diagnosis and localization of brain tumors is investigated. In order to analyze validity and reliability of the proposed method, two simulations were performed. (i) An in vitro experimental setup was designed and fabricated using a resistance heater embedded in agar tissue phantom in order to simulate heat generation by a tumor in the brain tissue; and (ii) A case report patient with parafalcine meningioma was presented to simulate ITI in the neurosurgical procedure. In the case report, both brain and tumor geometries were constructed from MRI data and tumor temperature and depth of location were estimated. For experimental tests, a novel assisted surgery robot was developed to palpate the tissue phantom surface to measure temperature variations and ANN was trained to estimate the simulated tumor’s power and depth. Results affirm that ITI based ATS is a non-invasive method which can be useful to detect, localize and characterize brain tumors.

Reality Imagined: The Choice to Use a Real-World Case in a Simulation

ERIC Educational Resources Information Center

Langfield, Danielle

2016-01-01

The use of a real-world case in a classroom simulation--in contrast to invented or disguised cases--is not widely recognized as a "combination" of two common active-learning strategies in political science: teaching with a case study and conducting a simulation. I argue that using such a simulation therefore can provide the benefits of…

Pitfalls of Ovarian Ablative Magnetic Resonance-guided Radiation Therapy for Refractory Endometriosis

PubMed Central

Tetar, Shyama; Bohoudi, Omar; Nieboer, Theodoor; Lagerwaard, Frank

2018-01-01

In this case presentation, we describe the challenges of performing magnetic resonance-guided radiation therapy (MRgRT) with plan adaptation in a patient with advanced endometriosis, in whom several prior therapeutic attempts were unsuccessful and extensive pelvic irradiation was regarded as being too toxic. Treatment was delivered in two sessions, first for the seemingly only active right ovary, and at a later stage for the left ovary. Some logistical problems were encountered during the preparation of the first treatment, which were subsequently optimized for the second treatment by using transvaginal ultrasound to determine the optimum time point for simulation and delivery. Using breath-hold gated delivery and plan adaptation, radiation dose to the bowel could be minimized, resulting in good tolerance of treatment. Because of the need to simulate and deliver in a brief optimal time span for visibility of the follicles in the ovaries, a single fraction dose of 8 Gy was used in our patient. Hormonal outcome after her second treatment is still pending. In conclusion, MRgRT with plan adaptation is feasible for the occasional patient with refractory endometriosis. Simulation and delivery needs to be synchronized with the menstrual cycle, ensuring that the Graafian follicles allow the ovaries to be visible on magnetic resonance imaging (MRI). Because the ovaries are only visible on T2-weighted MRI for a very brief period of time, we suggest that it is preferable to use single fraction radiotherapy with a brief interval between simulation imaging and delivery. PMID:29750135

Executing Medical Guidelines on the Web: Towards Next Generation Healthcare

NASA Astrophysics Data System (ADS)

Argüello, M.; Des, J.; Fernandez-Prieto, M. J.; Perez, R.; Paniagua, H.

There is still a lack of full integration between current Electronic Health Records (EHRs) and medical guidelines that encapsulate evidence-based medicine. Thus, general practitioners (GPs) and specialised physicians still have to read document-based medical guidelines and decide among various options for managing common non-life-threatening conditions where the selection of the most appropriate therapeutic option for each individual patient can be a difficult task. This paper presents a simulation framework and computational test-bed, called V.A.F. Framework, for supporting simulations of clinical situations that boosted the integration between Health Level Seven (HL7) and Semantic Web technologies (OWL, SWRL, and OWL-S) to achieve content layer interoperability between online clinical cases and medical guidelines, and therefore, it proves that higher integration between EHRs and evidence-based medicine can be accomplished which could lead to a next generation of healthcare systems that provide more support to physicians and increase patients' safety.

Quantitative analysis of surface electromyography during epileptic and nonepileptic convulsive seizures.

PubMed

Beniczky, Sándor; Conradsen, Isa; Moldovan, Mihai; Jennum, Poul; Fabricius, Martin; Benedek, Krisztina; Andersen, Noémi; Hjalgrim, Helle; Wolf, Peter

2014-07-01

To investigate the characteristics of sustained muscle activation during convulsive epileptic and psychogenic nonepileptic seizures (PNES), as compared to voluntary muscle activation. The main goal was to find surface electromyography (EMG) features that can distinguish between convulsive epileptic seizures and convulsive PNES. In this case-control study, surface EMG was recorded from the deltoid muscles during long-term video-electroencephalography (EEG) monitoring in 25 patients and in 21 healthy controls. A total of 46 clinical episodes were recorded: 28 generalized tonic-clonic seizures (GTCS) from 14 patients with epilepsy, and 18 convulsive PNES from 12 patients (one patient had both GTCS and PNES). The healthy controls were simulating GTCS. To quantitatively characterize the signals we calculated the following parameters: root mean square (RMS) of the amplitude, median frequency (MF), coherence, and duration of the seizures, of the clonic EMG discharges, and of the silent periods between the cloni. Based on wavelet analysis, we distinguished between a low-frequency component (LF 2-8 Hz) and a high-frequency component (HF 64-256 Hz). Duration of the seizure, and separation between the tonic and the clonic phases distinguished at group-level but not at individual level between convulsive PNES and GTCS. RMS, temporal dynamics of the HF/LF ratio, and the evolution of the silent periods differentiated between epileptic and nonepileptic convulsive seizures at the individual level. A combination between HF/LF ratio and RMS separated all PNES from the GTCS. A blinded review of the EMG features distinguished correctly between GTCS and convulsive PNES in all cases. The HF/LF ratio and the RMS of the PNES were smaller compared to the simulated seizures. In addition to providing insight into the mechanism of muscle activation during convulsive PNES, these results have diagnostic significance, at the individual level. Surface EMG features can accurately distinguish convulsive epileptic from nonepileptic psychogenic seizures, even in PNES cases without rhythmic clonic movements. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

Comparison of standardized patients with high-fidelity simulators for managing stress and improving performance in clinical deterioration: A mixed methods study.

PubMed

Ignacio, Jeanette; Dolmans, Diana; Scherpbier, Albert; Rethans, Jan-Joost; Chan, Sally; Liaw, Sok Ying

2015-12-01

The use of standardized patients in deteriorating patient simulations adds realism that can be valuable for preparing nurse trainees for stress and enhancing their performance during actual patient deterioration. Emotional engagement resulting from increased fidelity can provide additional stress for student nurses with limited exposure to real patients. To determine the presence of increased stress with the standardized patient modality, this study compared the use of standardized patients (SP) with the use of high-fidelity simulators (HFS) during deteriorating patient simulations. Performance in managing deteriorating patients was also compared. It also explored student nurses' insights on the use of standardized patients and patient simulators in deteriorating patient simulations as preparation for clinical placement. Fifty-seven student nurses participated in a randomized controlled design study with pre- and post-tests to evaluate stress and performance in deteriorating patient simulations. Performance was assessed using the Rescuing A Patient in Deteriorating Situations (RAPIDS) rating tool. Stress was measured using salivary alpha-amylase levels. Fourteen participants who joined the randomized controlled component then participated in focus group discussions that elicited their insights on SP use in patient deterioration simulations. Analysis of covariance (ANCOVA) results showed no significant difference (p=0.744) between the performance scores of the SP and HFS groups in managing deteriorating patients. Amylase levels were also not significantly different (p=0.317) between the two groups. Stress in simulation, awareness of patient interactions, and realism were the main themes that resulted from the thematic analysis. Performance and stress in deteriorating patient simulations with standardized patients did not vary from similar simulations using high-fidelity patient simulators. Data from focus group interviews, however, suggested that the use of standardized patients was perceived to be valuable in preparing students for actual patient deterioration management. Copyright © 2015 Elsevier Ltd. All rights reserved.

Does exposure to simulated patient cases improve accuracy of clinicians' predictive value estimates of diagnostic test results? A within-subjects experiment at St Michael's Hospital, Toronto, Canada.

PubMed

Armstrong, Bonnie; Spaniol, Julia; Persaud, Nav

2018-02-13

Clinicians often overestimate the probability of a disease given a positive test result (positive predictive value; PPV) and the probability of no disease given a negative test result (negative predictive value; NPV). The purpose of this study was to investigate whether experiencing simulated patient cases (ie, an 'experience format') would promote more accurate PPV and NPV estimates compared with a numerical format. Participants were presented with information about three diagnostic tests for the same fictitious disease and were asked to estimate the PPV and NPV of each test. Tests varied with respect to sensitivity and specificity. Information about each test was presented once in the numerical format and once in the experience format. The study used a 2 (format: numerical vs experience) × 3 (diagnostic test: gold standard vs low sensitivity vs low specificity) within-subjects design. The study was completed online, via Qualtrics (Provo, Utah, USA). 50 physicians (12 clinicians and 38 residents) from the Department of Family and Community Medicine at St Michael's Hospital in Toronto, Canada, completed the study. All participants had completed at least 1 year of residency. Estimation accuracy was quantified by the mean absolute error (MAE; absolute difference between estimate and true predictive value). PPV estimation errors were larger in the numerical format (MAE=32.6%, 95% CI 26.8% to 38.4%) compared with the experience format (MAE=15.9%, 95% CI 11.8% to 20.0%, d =0.697, P<0.001). Likewise, NPV estimation errors were larger in the numerical format (MAE=24.4%, 95% CI 14.5% to 34.3%) than in the experience format (MAE=11.0%, 95% CI 6.5% to 15.5%, d =0.303, P=0.015). Exposure to simulated patient cases promotes accurate estimation of predictive values in clinicians. This finding carries implications for diagnostic training and practice. © 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.

Association of Hospitalization for Neurosurgical Operations in Magnet Hospitals With Mortality and Length of Stay.

PubMed

Missios, Symeon; Bekelis, Kimon

2018-03-01

The association of Magnet hospital status with improved surgical outcomes remains an issue of debate. To investigate whether hospitalization in a Magnet hospital is associated with improved outcomes for patients undergoing neurosurgical operations. A cohort study was executed using all patients undergoing neurosurgical operations in New York registered in the Statewide Planning and Research Cooperative System database from 2009 to 2013. We examined the association of Magnet status hospitalization after neurosurgical operations with inpatient case fatality and length of stay (LOS). We employed an instrumental variable analysis to simulate a randomized trial. Overall, 190 787 patients underwent neurosurgical operations. Of these, 68 046 (35.7%) were hospitalized in Magnet hospitals, and 122 741 (64.3%) in non-Magnet institutions. Instrumental variable analysis demonstrated that hospitalization in Magnet hospitals was associated with decreased case fatality (adjusted difference, -0.8%; -95% confidence interval, -0.7% to -0.6%), and LOS (adjusted difference, -1.9; 95% confidence interval, -2.2 to -1.5) in comparison to non-Magnet hospitals. These associations were also observed in propensity score adjusted mixed effects models. These associations persisted in prespecified subgroups of patients undergoing spine surgery, craniotomy for tumor resection, or neurovascular interventions. We identified an association of Magnet hospitals with lower case fatality, and shorter LOS in a comprehensive New York State patient cohort undergoing neurosurgical procedures. Copyright © 2017 by the Congress of Neurological Surgeons

Treatment planning for heavy ion radiotherapy: clinical implementation and application.

PubMed

Jäkel, O; Krämer, M; Karger, C P; Debus, J

2001-04-01

The clinical implementation and application of a novel treatment planning system (TPS) for scanned ion beams is described, which is in clinical use for carbon ion treatments at the German heavy ion facility (GSI). All treatment plans are evaluated on the basis of biologically effective dose distributions. For therapy control, in-beam positron emission tomography (PET) and an online monitoring system for the beam intensity and position are used. The absence of a gantry restricts the treatment plans to horizontal beams. Most of the treatment plans consist of two nearly opposing lateral fields or sometimes orthogonal fields. In only a very few cases a single beam was used. For patients with very complex target volumes lateral and even distal field patching techniques were applied. Additional improvements can be achieved when the patient's head is fixed in a tilted position, in order to achieve sparing of the organs at risk. In order to test the stability of dose distributions in the case of patient misalignments we routinely simulate the effects of misalignments for patients with critical structures next to the target volume. The uncertainties in the range calculation are taken into account by a margin around the target volume of typically 2-3 mm, which can, however, be extended if the simulation demonstrates larger deviations. The novel TPS developed for scanned ion beams was introduced into clinical routine in December 1997 and was used for the treatment planning of 63 patients with head and neck tumours until July 2000. Planning strategies and methods were developed for this tumour location that facilitate the treatment of a larger number of patients with the scanned heavy ion beam in a clinical setting. Further developments aim towards a simultaneous optimization of the treatment field intensities and more effective procedures for the patient set-up. The results demonstrate that ion beams can be integrated into a clinical environment for treatment planning and delivery.

Multiblock High Order Large Eddy Simulation of Powered Fontan Hemodynamics: Towards Computational Surgery

PubMed Central

Delorme, Yann T.; Rodefeld, Mark D.; Frankel, Steven H.

2016-01-01

Children born with only one functional ventricle must typically undergo a series of three surgeries to obtain the so-called Fontan circulation in which the blood coming from the body passively flows from the Vena Cavae (VCs) to the Pulmonary Arteries (PAs) through the Total Cavopulmonary Connection (TCPC). The circulation is inherently inefficient due to the lack of a subpulmonary ventricle. Survivors face the risk of circulatory sequelae and eventual failure for the duration of their lives. Current efforts are focused on improving the outcomes of Fontan palliation, either passively by optimizing the TCPC, or actively by using mechanical support. We are working on a chronic implant that would be placed at the junction of the TCPC, and would provide the necessary pressure augmentation to re-establish a circulation that recapitulates a normal two-ventricle circulation. This implant is based on the Von Karman viscous pump and consists of a vaned impeller that rotates inside the TCPC. To evaluate the performance of such a device, and to study the flow features induced by the presence of the pump, Computational Fluid Dynamics (CFD) is used. CFD has become an important tool to understand hemodynamics owing to the possibility of simulating quickly a large number of designs and flow conditions without any harm for patients. The transitional and unsteady nature of the flow can make accurate simulations challenging. We developed and in-house high order Large Eddy Simulation (LES) solver coupled to a recent Immersed Boundary Method (IBM) to handle complex geometries. Multiblock capability is added to the solver to allow for efficient simulations of complex patient specific geometries. Blood simulations are performed in a complex patient specific TCPC geometry. In this study, simulations without mechanical assist are performed, as well as after virtual implantation of the temporary and chronic implants being developed. Instantaneous flow structures, hepatic factor distribution, and statistical data are presented for all three cases. PMID:28649147

Validation of a model to evaluate the role of radiographs in the diagnosis and treatment planning of periodontal diseases.

PubMed

Tugnait, A; Hirschmann, P N; Clerehugh, V

2006-08-01

The purposes of this study were (i) to see if an indirect method of design (paper patients) could be developed for study of change affected by radiographs on diagnostic outcome and planned treatment of periodontal patients and (ii) to investigate the effect of the nature of clinical examination on the value of radiographs in reaching a periodontal diagnosis. Paper cases could allow the design of examiner blind studies where repeatability could be assessed. 201 patients were assigned to one of four groups and clinically assessed according to group specifications. Radiographs were taken. Periodontal diagnoses and treatment plans were drawn up for each patient with and without radiographic information (real patient). Simulated paper transcriptions were made for each subject and diagnoses and treatment plans were again drawn up (paper patient). For many diagnoses and treatment options assessments were similar for real and paper patients. There was substantial agreement between periodontal diagnoses reached from real and paper assessments (kappa=0.68). Greater differences were seen for extractions and periodontal surgery. Paper assessments better replicated real assessments when more thorough clinical examinations were undertaken. The relatively time efficient Group 2 clinical assessment appeared to perform similarly to the extensive Group 4 clinical assessment. The model described may be useful for simulating real patients for studies of this nature. The Group 2 assessment appeared to give sufficient clinical information for patient management and may be an appropriate choice for initial diagnosis and treatment planning of periodontal patients.

Web-based radiology: a future to be created.

PubMed

Canadè, Adolfo; Palladino, Francesco; Pitzalis, Gianluca; Campioni, Paolo; Marano, Pasquale

2003-01-01

The impact of Internet on Medicine and Surgery is certainly remarkable, however the influence it had on Diagnostic Imaging was even stronger. The standardization of digital images acquired by the different medical imaging equipment has further facilitated the diffusion, transmission and communication in radiology within hospitals as well as on WEB. Radiology departments are bound to become "filmless" and with the present "tablet PC" radiological images will be directly transferred to the patient's bed in the relative electronic patient report. For radiology, interactive education could be envisaged with a tutor who guides the student(s) through the network. The Internet is an inexhaustible source of radiologic educational and information material with a number of sites of clinical cases, tutorial and teaching files, journals and magisterial lectures on-line. In a near future, the Internet could be applied in the simulation of clinicoradiologic cases or in applications of artificial intelligence with expert systems to support the solution of most complex cases.

SU-E-J-15: A Patient-Centered Scheme to Mitigate Impacts of Treatment Setup Error

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, L; Southern Medical University, Guangzhou; Tian, Z

2014-06-01

Purpose: Current Intensity Modulated Radiation Therapy (IMRT) is plan-centered. At each treatment fraction, we position the patient to match the setup in treatment plan. Inaccurate setup can compromise delivered dose distribution, and hence leading to suboptimal treatments. Moreover, current setup approach via couch shift under image guidance can correct translational errors, while rotational and deformation errors are hard to address. To overcome these problems, we propose in this abstract a patient-centered scheme to mitigate impacts of treatment setup errors. Methods: In the patient-centered scheme, we first position the patient on the couch approximately matching the planned-setup. Our Supercomputing Online Replanningmore » Environment (SCORE) is then employed to design an optimal treatment plan based on the daily patient geometry. It hence mitigates the impacts of treatment setup error and reduces the requirements on setup accuracy. We have conducted simulations studies in 10 head-and-neck (HN) patients to investigate the feasibility of this scheme. Rotational and deformation setup errors were simulated. Specifically, 1, 3, 5, 7 degrees of rotations were put on pitch, roll, and yaw directions; deformation errors were simulated by splitting neck movements into four basic types: rotation, lateral bending, flexion and extension. Setup variation ranges are based on observed numbers in previous studies. Dosimetric impacts of our scheme were evaluated on PTVs and OARs in comparison with original plan dose with original geometry and original plan recalculated dose with new setup geometries. Results: With conventional plan-centered approach, setup error could lead to significant PTV D99 decrease (−0.25∼+32.42%) and contralateral-parotid Dmean increase (−35.09∼+42.90%). The patientcentered approach is effective in mitigating such impacts to 0∼+0.20% and −0.03∼+5.01%, respectively. Computation time is <128 s. Conclusion: Patient-centered scheme is proposed to mitigate setup error impacts using replanning. Its superiority in terms of dosimetric impacts and feasibility has been shown through simulation studies on HN cases.« less

Anesthesia Technique and Outcomes of Mechanical Thrombectomy in Patients With Acute Ischemic Stroke.

PubMed

Bekelis, Kimon; Missios, Symeon; MacKenzie, Todd A; Tjoumakaris, Stavropoula; Jabbour, Pascal

2017-02-01

The impact of anesthesia technique on the outcomes of mechanical thrombectomy for acute ischemic stroke remains an issue of debate. We investigated the association of general anesthesia with outcomes in patients undergoing mechanical thrombectomy for ischemic stroke. We performed a cohort study involving patients undergoing mechanical thrombectomy for ischemic stroke from 2009 to 2013, who were registered in the New York Statewide Planning and Research Cooperative System database. An instrumental variable (hospital rate of general anesthesia) analysis was used to simulate the effects of randomization and investigate the association of anesthesia technique with case-fatality and length of stay. Among 1174 patients, 441 (37.6%) underwent general anesthesia and 733 (62.4%) underwent conscious sedation. Using an instrumental variable analysis, we identified that general anesthesia was associated with a 6.4% increased case-fatality (95% confidence interval, 1.9%-11.0%) and 8.4 days longer length of stay (95% confidence interval, 2.9-14.0) in comparison to conscious sedation. This corresponded to 15 patients needing to be treated with conscious sedation to prevent 1 death. Our results were robust in sensitivity analysis with mixed effects regression and propensity score-adjusted regression models. Using a comprehensive all-payer cohort of acute ischemic stroke patients undergoing mechanical thrombectomy in New York State, we identified an association of general anesthesia with increased case-fatality and length of stay. These considerations should be taken into account when standardizing acute stroke care. © 2017 American Heart Association, Inc.

Pseudo-acute myocardial infarction due to transient apical ventricular dysfunction syndrome (Takotsubo syndrome).

PubMed

Maciel, Bruno Araújo; Cidrão, Alan Alves de Lima; Sousa, Italo Bruno Dos Santos; Ferreira, José Adailson da Silva; Messias Neto, Valdevino Pedro

2013-03-01

Takotsubo syndrome is characterized by predominantly medial-apical transient left ventricular dysfunction, which is typically triggered by physical or emotional stress. The present article reports the case of a 61-year-old female patient presenting with dizziness, excessive sweating, and sudden state of ill feeling following an episode involving intense emotional stress. The physical examination and electrocardiogram were normal upon admission, but the troponin I and creatine kinase-MB concentrations were increased. Acute myocardial infarction without ST segment elevation was suspected, and coronary angiography was immediately performed, which showed severe diffuse left ventricular hypokinesia, medial-apical systolic ballooning, and a lack of significant coronary injury. The patient was referred to the intensive care unit and was successfully treated with supportive therapy. As this case shows, Takotsubo syndrome might simulate the clinical manifestations of acute myocardial infarction, and coronary angiography is necessary to distinguish between both myocardial infarction and myocardial infarction in the acute stage. The present patient progressed with spontaneous resolution of the ventricular dysfunction without any sequelae.

Case Mix Difference Can Affect Evaluation of Outcome of Treatment for Colorectal Cancer.

PubMed

Ljungman, David; Kodeda, Karl; Derwinger, Kristoffer

2015-07-01

To explore the potential effects of patient selection, for example by organization, on survival as outcome parameter in colorectal cancer treatment. The main cohort was identified in a Hospital-based registry and outcome data of all 2,717 patients operated on for colorectal cancer between 2000-2011 were evaluated. A simulation of different center settings was performed using several potential selection criteria, including emergency cases, referral surgery and palliative resection, and used for comparison of outcome data. Overall survival and cancer-specific survival can be significantly affected in both short-term (30-/90-day) mortality and long-term survival by factors of organizational level. Survival data as an outcome parameter can be affected by the composition of the patient cohort and thus reflect possible selection bias for example due to organization, referral patterns and practice customs. This potential bias should be acknowledged when making inter-hospital comparisons of outcome. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Pseudo-acute myocardial infarction due to transient apical ventricular dysfunction syndrome (Takotsubo syndrome)

PubMed Central

Maciel, Bruno Araújo; Cidrão, Alan Alves de Lima; Sousa, Ítalo Bruno dos Santos; Ferreira, José Adailson da Silva; Messias Neto, Valdevino Pedro

2013-01-01

Takotsubo syndrome is characterized by predominantly medial-apical transient left ventricular dysfunction, which is typically triggered by physical or emotional stress. The present article reports the case of a 61-year-old female patient presenting with dizziness, excessive sweating, and sudden state of ill feeling following an episode involving intense emotional stress. The physical examination and electrocardiogram were normal upon admission, but the troponin I and creatine kinase-MB concentrations were increased. Acute myocardial infarction without ST segment elevation was suspected, and coronary angiography was immediately performed, which showed severe diffuse left ventricular hypokinesia, medial-apical systolic ballooning, and a lack of significant coronary injury. The patient was referred to the intensive care unit and was successfully treated with supportive therapy. As this case shows, Takotsubo syndrome might simulate the clinical manifestations of acute myocardial infarction, and coronary angiography is necessary to distinguish between both myocardial infarction and myocardial infarction in the acute stage. The present patient progressed with spontaneous resolution of the ventricular dysfunction without any sequelae. PMID:23887762

Transperineal ultrasound-guided implantation of electromagnetic transponders in the prostatic fossa for localization and tracking during external beam radiation therapy.

PubMed

Garsa, Adam A; Verma, Vivek; Michalski, Jeff M; Gay, Hiram A

2014-01-01

To describe a transperineal ultrasound-guided technique for implantation of electromagnetic transponders into the prostatic fossa. Patients were placed in the dorsal lithotomy position, and local anesthetic was administered. On ultrasound, the bladder, urethra, vesicourethral anastomosis, rectum, and the prostatic fossa were carefully identified. Three transponders were implanted into the prostatic fossa under ultrasound guidance in a triangular configuration and implantation was verified by fluoroscopy. Patients underwent computed tomography (CT) simulation approximately 1 week later. All patients in this study were subsequently treated with intensity modulated radiation therapy (IMRT) to the prostatic fossa. From 2008 to 2012, 180 patients received transperineal implantation of electromagnetic transponders into the prostatic fossa and subsequently received IMRT. There were no cases of severe hematuria or rectal bleeding requiring intervention. There were no grade 3 or 4 toxicities. Three patients (1.7%) had a transponder missing on the subsequent CT simulation. Thirteen patients (7.3%) had transponder migration with a geometric residual that exceeded 2 mm for 3 consecutive days (5.6%) or rotation that exceeded 10 degrees for 5 consecutive days (1.7%). These patients underwent a resimulation CT scan to identify the new transponder coordinates. A transperineal technique for implantation of electromagnetic transponders into the prostatic fossa is safe and well tolerated, with no severe toxicity after implantation. There is a low rate of transponder loss or migration.

3D-printed soft-tissue physical models of renal malignancies for individualized surgical simulation: a feasibility study.

PubMed

Maddox, Michael M; Feibus, Allison; Liu, James; Wang, Julie; Thomas, Raju; Silberstein, Jonathan L

2018-03-01

To construct patient-specific physical three-dimensional (3D) models of renal units with materials that approximates the properties of renal tissue to allow pre-operative and robotic training surgical simulation, 3D physical kidney models were created (3DSystems, Rock Hill, SC) using computerized tomography to segment structures of interest (parenchyma, vasculature, collection system, and tumor). Images were converted to a 3D surface mesh file for fabrication using a multi-jet 3D printer. A novel construction technique was employed to approximate normal renal tissue texture, printers selectively deposited photopolymer material forming the outer shell of the kidney, and subsequently, an agarose gel solution was injected into the inner cavity recreating the spongier renal parenchyma. We constructed seven models of renal units with suspected malignancies. Partial nephrectomy and renorrhaphy were performed on each of the replicas. Subsequently all patients successfully underwent robotic partial nephrectomy. Average tumor diameter was 4.4 cm, warm ischemia time was 25 min, RENAL nephrometry score was 7.4, and surgical margins were negative. A comparison was made between the seven cases and the Tulane Urology prospectively maintained robotic partial nephrectomy database. Patients with surgical models had larger tumors, higher nephrometry score, longer warm ischemic time, fewer positive surgical margins, shorter hospitalization, and fewer post-operative complications; however, the only significant finding was lower estimated blood loss (186 cc vs 236; p = 0.01). In this feasibility study, pre-operative resectable physical 3D models can be constructed and used as patient-specific surgical simulation tools; further study will need to demonstrate if this results in improvement of surgical outcomes and robotic simulation education.

Development of real-time motion verification system using in-room optical images for respiratory-gated radiotherapy.

PubMed

Park, Yang-Kyun; Son, Tae-geun; Kim, Hwiyoung; Lee, Jaegi; Sung, Wonmo; Kim, Il Han; Lee, Kunwoo; Bang, Young-bong; Ye, Sung-Joon

2013-09-06

Phase-based respiratory-gated radiotherapy relies on the reproducibility of patient breathing during the treatment. To monitor the positional reproducibility of patient breathing against a 4D CT simulation, we developed a real-time motion verification system (RMVS) using an optical tracking technology. The system in the treatment room was integrated with a real-time position management system. To test the system, an anthropomorphic phantom that was mounted on a motion platform moved on a programmed breathing pattern and then underwent a 4D CT simulation with RPM. The phase-resolved anterior surface lines were extracted from the 4D CT data to constitute 4D reference lines. In the treatment room, three infrared reflective markers were attached on the superior, middle, and inferior parts of the phantom along with the body midline and then RMVS could track those markers using an optical camera system. The real-time phase information extracted from RPM was delivered to RMVS via in-house network software. Thus, the real-time anterior-posterior positions of the markers were simultaneously compared with the 4D reference lines. The technical feasibility of RMVS was evaluated by repeating the above procedure under several scenarios such as ideal case (with identical motion parameters between simulation and treatment), cycle change, baseline shift, displacement change, and breathing type changes (abdominal or chest breathing). The system capability for operating under irregular breathing was also investigated using real patient data. The evaluation results showed that RMVS has a competence to detect phase-matching errors between patient's motion during the treatment and 4D CT simulation. Thus, we concluded that RMVS could be used as an online quality assurance tool for phase-based gating treatments.

Effects of a System Thinking-Based Simulation Program for Congestive Heart Failure.

PubMed

Kim, Hyeon-Young; Yun, Eun Kyoung

2018-03-01

This study evaluated a system thinking-based simulation program for the care of patients with congestive heart failure. Participants were 67 undergraduate nursing students from a nursing college in Seoul, South Korea. The experimental group was given a 4-hour system-thinking program and a 2-hour simulation program, whereas the control group had a 4-hour case study and a 2-hour simulation program. There were significant improvements in critical thinking in both groups, but no significant group differences between educational methods (F = 3.26, P = .076). Problem-solving ability in the experimental group was significantly higher than in the control group (F = 5.04, P = .028). Clinical competency skills in the experimental group were higher than in the control group (t = 2.12, P = .038). A system thinking-based simulation program is a more effective learning method in terms of problem-solving ability and clinical competency skills compared to the existing simulation program. Further research using a longitudinal study is needed to test the long-term effect of the intervention and apply it to the nursing curriculum.

Safety interventions on the labor and delivery unit.

PubMed

Kacmar, Rachel M

2017-06-01

The present review highlights recent advances in efforts to improve patient safety on labor and delivery units and well tolerated care for pregnant patients in general. Recent studies in obstetric patient safety have a broad focus but repetitive themes for interdisciplinary training include: simulating critical events, having open multidisciplinary communication, frequent reviews of cases of maternal morbidity, and implementing maternal early warning systems. The National Partnership for Maternal Safety is also active in promoting care bundles across many topics on maternal safety. A culture of safety is the goal for all obstetric units. Achieving that ideal requires multidisciplinary collaboration, frequent reassessment for areas of improvement, and a culture of openness to change when improvement opportunities arise.

Estimated dose rates to members of the public from external exposure to patients with 131I thyroid treatment

DOE PAGES

Dewji, S.; Bellamy, M.; Hertel, N.; ...

2015-03-25

The purpose of this study is to estimate dose rates that may result from exposure to patients who had been administered iodine-131 ( 131I) as part of medical therapy were calculated. These effective dose rate estimates were compared with simplified assumptions under United States Nuclear Regulatory Commission Regulatory Guide 8.39, which does not consider body tissue attenuation nor time-dependent redistribution and excretion of the administered 131I. Methods: Dose rates were estimated for members of the public potentially exposed to external irradiation from patients recently treated with 131I. Tissue attenuation and iodine biokinetics were considered in the patient in a largermore » comprehensive effort to improve external dose rate estimates. The external dose rate estimates are based on Monte Carlo simulations using the Phantom with Movable Arms and Legs (PIMAL), previously developed by Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission. PIMAL was employed to model the relative positions of the 131I patient and members of the public in three exposure scenarios: (1) traveling on a bus in a total of six seated or standing permutations, (2) two nursing home cases where a caregiver is seated at 30 cm from the patient’s bedside and a nursing home resident seated 250 cm away from the patient in an adjacent bed, and (3) two hotel cases where the patient and a guest are in adjacent rooms with beds on opposite sides of the common wall, with the patient and guest both in bed and either seated back-to-back or lying head to head. The biokinetic model predictions of the retention and distribution of 131I in the patient assumed a single voiding of urinary bladder contents that occurred during the trip at 2, 4, or 8 h after 131I administration for the public transportation cases, continuous first-order voiding for the nursing home cases, and regular periodic voiding at 4, 8, or 12 h after administration for the hotel room cases. Organ specific activities of 131I in the thyroid, bladder, and combined remaining tissues were calculated as a function of time after administration. Exposures to members of the public were considered for 131I patients with normal thyroid uptake (peak thyroid uptake of ~27% of administered 131I), differentiated thyroid cancer (DTC, 5% uptake), and hyperthyroidism (80% uptake). Results: The scenario with the patient seated behind the member of the public yielded the highest dose rate estimate of seated public transportation exposure cases. The dose rate to the adjacent room guest was highest for the exposure scenario in which the hotel guest and patient are seated by a factor of ~4 for the normal and differentiated thyroid cancer uptake cases and by a factor of ~3 for the hyperthyroid case. Conclusions: It was determined that for all modeled cases, the DTC case yielded the lowest external dose rates, whereas the hyperthyroid case yielded the highest dose rates. In estimating external dose to members of the public from patients with 131I therapy, consideration must be given to (patient- and case-specific) administered 131I activities and duration of exposure for a more complete estimate. The method implemented here included a detailed calculation model, which provides a means to determine dose rate estimates for a range of scenarios. Finally, the method was demonstrated for variations of three scenarios, showing how dose rates are expected to vary with uptake, voiding pattern, and patient location.« less

Estimated dose rates to members of the public from external exposure to patients with 131I thyroid treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dewji, S.; Bellamy, M.; Hertel, N.

The purpose of this study is to estimate dose rates that may result from exposure to patients who had been administered iodine-131 ( 131I) as part of medical therapy were calculated. These effective dose rate estimates were compared with simplified assumptions under United States Nuclear Regulatory Commission Regulatory Guide 8.39, which does not consider body tissue attenuation nor time-dependent redistribution and excretion of the administered 131I. Methods: Dose rates were estimated for members of the public potentially exposed to external irradiation from patients recently treated with 131I. Tissue attenuation and iodine biokinetics were considered in the patient in a largermore » comprehensive effort to improve external dose rate estimates. The external dose rate estimates are based on Monte Carlo simulations using the Phantom with Movable Arms and Legs (PIMAL), previously developed by Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission. PIMAL was employed to model the relative positions of the 131I patient and members of the public in three exposure scenarios: (1) traveling on a bus in a total of six seated or standing permutations, (2) two nursing home cases where a caregiver is seated at 30 cm from the patient’s bedside and a nursing home resident seated 250 cm away from the patient in an adjacent bed, and (3) two hotel cases where the patient and a guest are in adjacent rooms with beds on opposite sides of the common wall, with the patient and guest both in bed and either seated back-to-back or lying head to head. The biokinetic model predictions of the retention and distribution of 131I in the patient assumed a single voiding of urinary bladder contents that occurred during the trip at 2, 4, or 8 h after 131I administration for the public transportation cases, continuous first-order voiding for the nursing home cases, and regular periodic voiding at 4, 8, or 12 h after administration for the hotel room cases. Organ specific activities of 131I in the thyroid, bladder, and combined remaining tissues were calculated as a function of time after administration. Exposures to members of the public were considered for 131I patients with normal thyroid uptake (peak thyroid uptake of ~27% of administered 131I), differentiated thyroid cancer (DTC, 5% uptake), and hyperthyroidism (80% uptake). Results: The scenario with the patient seated behind the member of the public yielded the highest dose rate estimate of seated public transportation exposure cases. The dose rate to the adjacent room guest was highest for the exposure scenario in which the hotel guest and patient are seated by a factor of ~4 for the normal and differentiated thyroid cancer uptake cases and by a factor of ~3 for the hyperthyroid case. Conclusions: It was determined that for all modeled cases, the DTC case yielded the lowest external dose rates, whereas the hyperthyroid case yielded the highest dose rates. In estimating external dose to members of the public from patients with 131I therapy, consideration must be given to (patient- and case-specific) administered 131I activities and duration of exposure for a more complete estimate. The method implemented here included a detailed calculation model, which provides a means to determine dose rate estimates for a range of scenarios. Finally, the method was demonstrated for variations of three scenarios, showing how dose rates are expected to vary with uptake, voiding pattern, and patient location.« less

Influence of learner knowledge and case complexity on handover accuracy and cognitive load: results from a simulation study.

PubMed

Young, John Q; van Dijk, Savannah M; O'Sullivan, Patricia S; Custers, Eugene J; Irby, David M; Ten Cate, Olle

2016-09-01

The handover represents a high-risk event in which errors are common and lead to patient harm. A better understanding of the cognitive mechanisms of handover errors is essential to improving handover education and practice. This paper reports on an experiment conducted to study the effects of learner knowledge, case complexity (i.e. cases with or without a clear diagnosis) and their interaction on handover accuracy and cognitive load. Participants were 52 Dutch medical students in Years 2 and 6. The experiment employed a repeated-measures design with two explanatory variables: case complexity (simple or complex) as the within-subject variable, and learner knowledge (as indicated by illness script maturity) as the between-subject covariate. The dependent variables were handover accuracy and cognitive load. Each participant performed a total of four simulated handovers involving two simple cases and two complex cases. Higher illness script maturity predicted increased handover accuracy (p < 0.001) and lower cognitive load (p = 0.007). Case complexity did not independently affect either outcome. For handover accuracy, there was no interaction between case complexity and illness script maturity. For cognitive load, there was an interaction effect between illness script maturity and case complexity, indicating that more mature illness scripts reduced cognitive load less in complex cases than in simple cases. Students with more mature illness scripts performed more accurate handovers and experienced lower cognitive load. For cognitive load, these effects were more pronounced in simple than complex cases. If replicated, these findings suggest that handover curricula and protocols should provide support that varies according to the knowledge of the trainee. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Performance of the Self Referencing Interferometer in the Presence of Simulated Deep Turbulence and Noise Effects

DTIC Science & Technology

2013-12-01

experimental and simulated cases at Rytov number 0.044...21 Figure 9. Branch point occurrence for experimental and simulated cases at Rytov number 0.044...22 Figure 10. Unwrapped phase data for experimental and simulated cases at Rytov number 0.044

DDS: The Dental Diagnostic Simulation System.

ERIC Educational Resources Information Center

Tira, Daniel E.

The Dental Diagnostic Simulation (DDS) System provides an alternative to simulation systems which represent diagnostic case studies of relatively limited scope. It may be used to generate simulated case studies in all of the dental specialty areas with case materials progressing through the gamut of the diagnostic process. The generation of a…

Use case driven approach to develop simulation model for PCS of APR1400 simulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong Wook, Kim; Hong Soo, Kim; Hyeon Tae, Kang

2006-07-01

The full-scope simulator is being developed to evaluate specific design feature and to support the iterative design and validation in the Man-Machine Interface System (MMIS) design of Advanced Power Reactor (APR) 1400. The simulator consists of process model, control logic model, and MMI for the APR1400 as well as the Power Control System (PCS). In this paper, a use case driven approach is proposed to develop a simulation model for PCS. In this approach, a system is considered from the point of view of its users. User's view of the system is based on interactions with the system and themore » resultant responses. In use case driven approach, we initially consider the system as a black box and look at its interactions with the users. From these interactions, use cases of the system are identified. Then the system is modeled using these use cases as functions. Lower levels expand the functionalities of each of these use cases. Hence, starting from the topmost level view of the system, we proceeded down to the lowest level (the internal view of the system). The model of the system thus developed is use case driven. This paper will introduce the functionality of the PCS simulation model, including a requirement analysis based on use case and the validation result of development of PCS model. The PCS simulation model using use case will be first used during the full-scope simulator development for nuclear power plant and will be supplied to Shin-Kori 3 and 4 plant. The use case based simulation model development can be useful for the design and implementation of simulation models. (authors)« less

Simulated Conversations With Virtual Humans to Improve Patient-Provider Communication and Reduce Unnecessary Prescriptions for Antibiotics: A Repeated Measure Pilot Study

PubMed Central

2017-01-01

Background Despite clear evidence that antibiotics do not cure viral infections, the problem of unnecessary prescribing of antibiotics in ambulatory care persists, and in some cases, prescribing patterns have increased. The overuse of antibiotics for treating viral infections has created numerous economic and clinical consequences including increased medical costs due to unnecessary hospitalizations, antibiotic resistance, disruption of gut bacteria, and obesity. Recent research has underscored the importance of collaborative patient-provider communication as a means to reduce the high rates of unnecessary prescriptions for antibiotics. However, most patients and providers do not feel prepared to engage in such challenging conversations. Objectives The aim of this pilot study was to assess the ability of a brief 15-min simulated role-play conversation with virtual humans to serve as a preliminary step to help health care providers and patients practice, and learn how to engage in effective conversations about antibiotics overuse. Methods A total of 69 participants (35 providers and 34 patients) completed the simulation once in one sitting. A pre-post repeated measures design was used to assess changes in patients’ and providers’ self-reported communication behaviors, activation, and preparedness, intention, and confidence to effectively communicate in the patient-provider encounter. Changes in patients’ knowledge and beliefs regarding antibiotic use were also evaluated. Results Patients experienced a short-term positive improvement in beliefs about appropriate antibiotic use for infection (F1,30=14.10, P=.001). Knowledge scores regarding the correct uses of antibiotics improved immediately postsimulation, but decreased at the 1-month follow-up (F1,30=31.16, P<.001). There was no change in patient activation and shared decision-making (SDM) scores in the total sample of patients (P>.10) Patients with lower levels of activation exhibited positive, short-term benefits in increased intent and confidence to discuss their needs and ask questions in the clinic visit, positive attitudes regarding participation in SDM with their provider, and accurate beliefs about the use of antibiotics (P<.10). The results also suggest small immediate gains in providers’ attitudes about SDM (mean change 0.20; F1,33= 8.03, P=.01). Conclusions This pilot study provided preliminary evidence on the efficacy of the use of simulated conversations with virtual humans as a tool to improve patient-provider communication (ie, through increasing patient confidence to actively participate in the visit and physician attitudes about SDM) for engaging in conversations about antibiotic use. Future research should explore if repeated opportunities to use the 15-min simulation as well as providing users with several different conversations to practice with would result in sustained improvements in antibiotics beliefs and knowledge and communication behaviors over time. The results of this pilot study offered several opportunities to improve on the simulation in order to bolster communication skills and knowledge retention. PMID:28428160

The effect of coaching on the simulated malingering of memory impairment.

PubMed

Rüsseler, Jascha; Brett, Alexandra; Klaue, Ulrike; Sailer, Michael; Münte, Thomas F

2008-10-07

Detecting malingering or exaggeration of impairments in brain function after traumatic brain injury is of increasing importance in neuropsychological assessment. Lawyers involved in brain injury litigation cases routinely coach their clients how to approach neuropsychological testing to their advantage. Thus, it is important to know how robust assessment methods are with respect to symptom malingering or exaggeration. The influence of different coaching methods on the simulated malingering of memory impairments is investigated in neurologically healthy participants using the Short-Term-Memory Test from the Bremer Symptom-Validierung (STM-BSV). Cut-offs were derived from patients with mild to severe traumatic brain injury. For comparison purposes, the German adaptation of the Rey Auditory Verbal Learning Test (AVLT), and the Rey 15 Items Test (FIT) were additionally administered. Four groups of neurologically healthy subjects were instructed to (1) perform as best as they can, (2) simulate brain injury, (3) simulate brain injury and received additional information about the sequelae of head trauma, (4) simulate brain injury and received additional information on how to avoid detection. Furthermore, a group of patients with mild to severe closed head injury performed the tests with best effort. The naïve simulator and the symptom coached groups were the easiest to detect, whereas the symptom plus test coached group was the hardest to detect. The AVLT and the FIT were not suited to detect simulators (sensitivities from 0% to 50.8% at 75% specificity) whereas the STM-BSV detected simulators with 67% - 88% sensitivity at a specificity of 73%. However, the STM-BSV was not robust to coaching. The present investigation shows that symptom validity testing as implemented in the BSV-STM is one clinically useful element in the detection of memory malingering. However, clinicians have to be aware that coaching influences performance in the test.

Computer-assisted design and finite element simulation of braces for the treatment of adolescent idiopathic scoliosis using a coronal plane radiograph and surface topography.

PubMed

Pea, Rany; Dansereau, Jean; Caouette, Christiane; Cobetto, Nikita; Aubin, Carl-Éric

2018-05-01

Orthopedic braces made by Computer-Aided Design and Manufacturing and numerical simulation were shown to improve spinal deformities correction in adolescent idiopathic scoliosis while using less material. Simulations with BraceSim (Rodin4D, Groupe Lagarrigue, Bordeaux, France) require a sagittal radiograph, not always available. The objective was to develop an innovative modeling method based on a single coronal radiograph and surface topography, and assess the effectiveness of braces designed with this approach. With a patient coronal radiograph and a surface topography, the developed method allowed the 3D reconstruction of the spine, rib cage and pelvis using geometric models from a database and a free form deformation technique. The resulting 3D reconstruction converted into a finite element model was used to design and simulate the correction of a brace. The developed method was tested with data from ten scoliosis cases. The simulated correction was compared to analogous simulations performed with a 3D reconstruction built using two radiographs and surface topography (validated gold standard reference). There was an average difference of 1.4°/1.7° for the thoracic/lumbar Cobb angle, and 2.6°/5.5° for the kyphosis/lordosis between the developed reconstruction method and the reference. The average difference of the simulated correction was 2.8°/2.4° for the thoracic/lumbar Cobb angles and 3.5°/5.4° the kyphosis/lordosis. This study showed the feasibility to design and simulate brace corrections based on a new modeling method with a single coronal radiograph and surface topography. This innovative method could be used to improve brace designs, at a lesser radiation dose for the patient. Copyright © 2018 Elsevier Ltd. All rights reserved.

Simulation of Benchmark Cases with the Terminal Area Simulation System (TASS)

NASA Technical Reports Server (NTRS)

Ahmad, Nash'at; Proctor, Fred

2011-01-01

The hydrodynamic core of the Terminal Area Simulation System (TASS) is evaluated against different benchmark cases. In the absence of closed form solutions for the equations governing atmospheric flows, the models are usually evaluated against idealized test cases. Over the years, various authors have suggested a suite of these idealized cases which have become standards for testing and evaluating the dynamics and thermodynamics of atmospheric flow models. In this paper, simulations of three such cases are described. In addition, the TASS model is evaluated against a test case that uses an exact solution of the Navier-Stokes equations. The TASS results are compared against previously reported simulations of these banchmark cases in the literature. It is demonstrated that the TASS model is highly accurate, stable and robust.

Simulation of Benchmark Cases with the Terminal Area Simulation System (TASS)

NASA Technical Reports Server (NTRS)

Ahmad, Nashat N.; Proctor, Fred H.

2011-01-01

The hydrodynamic core of the Terminal Area Simulation System (TASS) is evaluated against different benchmark cases. In the absence of closed form solutions for the equations governing atmospheric flows, the models are usually evaluated against idealized test cases. Over the years, various authors have suggested a suite of these idealized cases which have become standards for testing and evaluating the dynamics and thermodynamics of atmospheric flow models. In this paper, simulations of three such cases are described. In addition, the TASS model is evaluated against a test case that uses an exact solution of the Navier-Stokes equations. The TASS results are compared against previously reported simulations of these benchmark cases in the literature. It is demonstrated that the TASS model is highly accurate, stable and robust.

Transcranial phase aberration correction using beam simulations and MR-ARFI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vyas, Urvi, E-mail: urvi.vyas@gmail.com; Kaye, Elena; Pauly, Kim Butts

2014-03-15

Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focusedmore » ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus.« less

Identification of Patient Zero in Static and Temporal Networks: Robustness and Limitations

NASA Astrophysics Data System (ADS)

Antulov-Fantulin, Nino; Lančić, Alen; Šmuc, Tomislav; Štefančić, Hrvoje; Šikić, Mile

2015-06-01

Detection of patient zero can give new insights to epidemiologists about the nature of first transmissions into a population. In this Letter, we study the statistical inference problem of detecting the source of epidemics from a snapshot of spreading on an arbitrary network structure. By using exact analytic calculations and Monte Carlo estimators, we demonstrate the detectability limits for the susceptible-infected-recovered model, which primarily depend on the spreading process characteristics. Finally, we demonstrate the applicability of the approach in a case of a simulated sexually transmitted infection spreading over an empirical temporal network of sexual interactions.

Primary Mucinous Cystadenocarcinoma of the Breast with Endocervical-Like Mucinous Epithelium

PubMed Central

Lin, Dong-Liang; Hu, Ji-Lin; Shao, Shi-Hong; Sun, Dong-Mei; Wang, Ji-Gang

2013-01-01

Summary Background Primary mucinous cystadenocarcinoma of the breast is an extremely rare entity. To the best of our knowledge, only 17 patients have been described in the PubMed database. Case Report Here, we report a primary breast mucinous cystadenocarcinoma with endocervical-like mucinous epithelium in a 62-year-old woman. The patient was followed for 5 months without any adjuvant treatment and she continues to be disease free. Conclusions Primary breast mucinous cystadenocarcinoma usually displays unique pathologic and immunohistochemical characteristics simulating its ovarian counterparts; it seems to have a good prognosis after complete resection. PMID:24550753

Cost Utility Analysis of Topical Steroids Compared With Dietary Elimination for Treatment of Eosinophilic Esophagitis.

PubMed

Cotton, Cary C; Erim, Daniel; Eluri, Swathi; Palmer, Sarah H; Green, Daniel J; Wolf, W Asher; Runge, Thomas M; Wheeler, Stephanie; Shaheen, Nicholas J; Dellon, Evan S

2017-06-01

Topical corticosteroids or dietary elimination are recommended as first-line therapies for eosinophilic esophagitis, but data to directly compare these therapies are scant. We performed a cost utility comparison of topical corticosteroids and the 6-food elimination diet (SFED) in treatment of eosinophilic esophagitis, from the payer perspective. We used a modified Markov model based on current clinical guidelines, in which transition between states depended on histologic response simulated at the individual cohort-member level. Simulation parameters were defined by systematic review and meta-analysis to determine the base-case estimates and bounds of uncertainty for sensitivity analysis. Meta-regression models included adjustment for differences in study and cohort characteristics. In the base-case scenario, topical fluticasone was about as effective as SFED but more expensive at a 5-year time horizon ($9261.58 vs $5719.72 per person). SFED was more effective and less expensive than topical fluticasone and topical budesonide in the base-case scenario. Probabilistic sensitivity analysis revealed little uncertainty in relative treatment effectiveness. There was somewhat greater uncertainty in the relative cost of treatments; most simulations found SFED to be less expensive. In a cost utility analysis comparing topical corticosteroids and SFED for first-line treatment of eosinophilic esophagitis, the therapies were similar in effectiveness. SFED was on average less expensive, and more cost effective in most simulations, than topical budesonide and topical fluticasone, from a payer perspective and not accounting for patient-level costs or quality of life. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, A. Kyle, E-mail: kyle.jones@mdanderson.org

Purpose: To evaluate the sensitivity of the diagnostic radiological index of protection (DRIP), used to quantify the protective value of radioprotective garments, to procedural factors in fluoroscopy in an effort to determine an appropriate set of scatter-mimicking primary beams to be used in measuring the DRIP. Methods: Monte Carlo simulations were performed to determine the shape of the scattered x-ray spectra incident on the operator in different clinical fluoroscopy scenarios, including interventional radiology and interventional cardiology (IC). Two clinical simulations studied the sensitivity of the scattered spectrum to gantry angle and patient size, while technical factors were varied according tomore » measured automatic dose rate control (ADRC) data. Factorial simulations studied the sensitivity of the scattered spectrum to gantry angle, field of view, patient size, and beam quality for constant technical factors. Average energy (E{sub avg}) was the figure of merit used to condense fluence in each energy bin to a single numerical index. Results: Beam quality had the strongest influence on the scattered spectrum in fluoroscopy. Many procedural factors affect the scattered spectrum indirectly through their effect on primary beam quality through ADRC, e.g., gantry angle and patient size. Lateral C-arm rotation, common in IC, increased the energy of the scattered spectrum, regardless of the direction of rotation. The effect of patient size on scattered radiation depended on ADRC characteristics, patient size, and procedure type. Conclusions: The scattered spectrum striking the operator in fluoroscopy is most strongly influenced by primary beam quality, particularly kV. Use cases for protective garments should be classified by typical procedural primary beam qualities, which are governed by the ADRC according to the impacts of patient size, anatomical location, and gantry angle.« less

Sensitivity of the diagnostic radiological index of protection to procedural factors in fluoroscopy.

PubMed

Jones, A Kyle; Pasciak, Alexander S; Wagner, Louis K

2016-07-01

To evaluate the sensitivity of the diagnostic radiological index of protection (DRIP), used to quantify the protective value of radioprotective garments, to procedural factors in fluoroscopy in an effort to determine an appropriate set of scatter-mimicking primary beams to be used in measuring the DRIP. Monte Carlo simulations were performed to determine the shape of the scattered x-ray spectra incident on the operator in different clinical fluoroscopy scenarios, including interventional radiology and interventional cardiology (IC). Two clinical simulations studied the sensitivity of the scattered spectrum to gantry angle and patient size, while technical factors were varied according to measured automatic dose rate control (ADRC) data. Factorial simulations studied the sensitivity of the scattered spectrum to gantry angle, field of view, patient size, and beam quality for constant technical factors. Average energy (Eavg) was the figure of merit used to condense fluence in each energy bin to a single numerical index. Beam quality had the strongest influence on the scattered spectrum in fluoroscopy. Many procedural factors affect the scattered spectrum indirectly through their effect on primary beam quality through ADRC, e.g., gantry angle and patient size. Lateral C-arm rotation, common in IC, increased the energy of the scattered spectrum, regardless of the direction of rotation. The effect of patient size on scattered radiation depended on ADRC characteristics, patient size, and procedure type. The scattered spectrum striking the operator in fluoroscopy is most strongly influenced by primary beam quality, particularly kV. Use cases for protective garments should be classified by typical procedural primary beam qualities, which are governed by the ADRC according to the impacts of patient size, anatomical location, and gantry angle.

Improving Social Cognition in People with Schizophrenia with RC2S: Two Single-Case Studies.

PubMed

Peyroux, Elodie; Franck, Nicolas

2016-01-01

Difficulties in social interactions are a central characteristic of people with schizophrenia, and can be partly explained by impairments of social cognitive processes. New strategies of cognitive remediation have been recently developed to target these deficits. The RC2S therapy is an individualized and partly computerized program through which patients practice social interactions and develop social cognitive abilities with simulation techniques in a realistic environment. Here, we present the results of two case-studies involving two patients with schizophrenia presenting with specific profiles of impaired social cognition. Each patient completed three baseline sessions, 14 treatment sessions, and 3 follow-up sessions at the end of the therapy - and for 1 patient, another 3 sessions 9 months later. We used a multiple baseline design to assess specific components of social cognition according to the patients' profiles. Functioning and symptomatology were also assessed at the end of the treatment and 6 months later. Results highlight significant improvements in the targeted social cognitive processes and positive changes in functioning in the long term. The RC2S program seems, thus, to be a new useful program for social cognitive remediation in schizophrenia.

Independent dose verification system with Monte Carlo simulations using TOPAS for passive scattering proton therapy at the National Cancer Center in Korea

NASA Astrophysics Data System (ADS)

Shin, Wook-Geun; Testa, Mauro; Kim, Hak Soo; Jeong, Jong Hwi; Byeong Lee, Se; Kim, Yeon-Joo; Min, Chul Hee

2017-10-01

For the independent validation of treatment plans, we developed a fully automated Monte Carlo (MC)-based patient dose calculation system with the tool for particle simulation (TOPAS) and proton therapy machine installed at the National Cancer Center in Korea to enable routine and automatic dose recalculation for each patient. The proton beam nozzle was modeled with TOPAS to simulate the therapeutic beam, and MC commissioning was performed by comparing percent depth dose with the measurement. The beam set-up based on the prescribed beam range and modulation width was automated by modifying the vendor-specific method. The CT phantom was modeled based on the DICOM CT files with TOPAS-built-in function, and an in-house-developed C++ code directly imports the CT files for positioning the CT phantom, RT-plan file for simulating the treatment plan, and RT-structure file for applying the Hounsfield unit (HU) assignment, respectively. The developed system was validated by comparing the dose distributions with those calculated by the treatment planning system (TPS) for a lung phantom and two patient cases of abdomen and internal mammary node. The results of the beam commissioning were in good agreement of up to 0.8 mm2 g-1 for B8 option in both of the beam range and the modulation width of the spread-out Bragg peaks. The beam set-up technique can predict the range and modulation width with an accuracy of 0.06% and 0.51%, respectively, with respect to the prescribed range and modulation in arbitrary points of B5 option (128.3, 132.0, and 141.2 mm2 g-1 of range). The dose distributions showed higher than 99% passing rate for the 3D gamma index (3 mm distance to agreement and 3% dose difference) between the MC simulations and the clinical TPS in the target volume. However, in the normal tissues, less favorable agreements were obtained for the radiation treatment planning with the lung phantom and internal mammary node cases. The discrepancies might come from the limitations of the clinical TPS, which is the inaccurate dose calculation algorithm for the scattering effect, in the range compensator and inhomogeneous material. Moreover, the steep slope of the compensator, conversion of the HU values to the human phantom, and the dose calculation algorithm for the HU assignment also could be reasons of the discrepancies. The current study could be used for the independent dose validation of treatment plans including high inhomogeneities, the steep compensator, and riskiness such as lung, head & neck cases. According to the treatment policy, the dose discrepancies predicted with MC could be used for the acceptance decision of the original treatment plan.

TH-A-19A-11: Validation of GPU-Based Monte Carlo Code (gPMC) Versus Fully Implemented Monte Carlo Code (TOPAS) for Proton Radiation Therapy: Clinical Cases Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giantsoudi, D; Schuemann, J; Dowdell, S

Purpose: For proton radiation therapy, Monte Carlo simulation (MCS) methods are recognized as the gold-standard dose calculation approach. Although previously unrealistic due to limitations in available computing power, GPU-based applications allow MCS of proton treatment fields to be performed in routine clinical use, on time scales comparable to that of conventional pencil-beam algorithms. This study focuses on validating the results of our GPU-based code (gPMC) versus fully implemented proton therapy based MCS code (TOPAS) for clinical patient cases. Methods: Two treatment sites were selected to provide clinical cases for this study: head-and-neck cases due to anatomical geometrical complexity (air cavitiesmore » and density heterogeneities), making dose calculation very challenging, and prostate cases due to higher proton energies used and close proximity of the treatment target to sensitive organs at risk. Both gPMC and TOPAS methods were used to calculate 3-dimensional dose distributions for all patients in this study. Comparisons were performed based on target coverage indices (mean dose, V90 and D90) and gamma index distributions for 2% of the prescription dose and 2mm. Results: For seven out of eight studied cases, mean target dose, V90 and D90 differed less than 2% between TOPAS and gPMC dose distributions. Gamma index analysis for all prostate patients resulted in passing rate of more than 99% of voxels in the target. Four out of five head-neck-cases showed passing rate of gamma index for the target of more than 99%, the fifth having a gamma index passing rate of 93%. Conclusion: Our current work showed excellent agreement between our GPU-based MCS code and fully implemented proton therapy based MC code for a group of dosimetrically challenging patient cases.« less

Degrees of reality: airway anatomy of high-fidelity human patient simulators and airway trainers.

PubMed

Schebesta, Karl; Hüpfl, Michael; Rössler, Bernhard; Ringl, Helmut; Müller, Michael P; Kimberger, Oliver

2012-06-01

Human patient simulators and airway training manikins are widely used to train airway management skills to medical professionals. Furthermore, these patient simulators are employed as standardized "patients" to evaluate airway devices. However, little is known about how realistic these patient simulators and airway-training manikins really are. This trial aimed to evaluate the upper airway anatomy of four high-fidelity patient simulators and two airway trainers in comparison with actual patients by means of radiographic measurements. The volume of the pharyngeal airspace was the primary outcome parameter. Computed tomography scans of 20 adult trauma patients without head or neck injuries were compared with computed tomography scans of four high-fidelity patient simulators and two airway trainers. By using 14 predefined distances, two cross-sectional areas and three volume parameters of the upper airway, the manikins' similarity to a human patient was assessed. The pharyngeal airspace of all manikins differed significantly from the patients' pharyngeal airspace. The HPS Human Patient Simulator (METI®, Sarasota, FL) was the most realistic high-fidelity patient simulator (6/19 [32%] of all parameters were within the 95% CI of human airway measurements). The airway anatomy of four high-fidelity patient simulators and two airway trainers does not reflect the upper airway anatomy of actual patients. This finding may impact airway training and confound comparative airway device studies.

Effect of station examination item sampling on generalizability of student performance.

PubMed

Stratford, P W; Thomson, M A; Sanford, J; Saarinen, H; Dilworth, P; Solomon, P; Nixon, P; Fraser-MacDougall, V; Pierce-Fenn, H

1990-01-01

This article may be of interest to physical therapy educators who are responsible for structuring station or practical examinations used to evaluate physical therapy students. The global intent of the article is to provide information that may be useful in selecting test items. Specifically, the purposes of this study were 1) to examine how two item-sampling strategies (one based on different diagnostic concepts, or diagnostic probes, and the other based on different anatomical sites) influenced the generalizability of a station examination, 2) to determine the interrater reliability during the station examination, and 3) to determine whether the status of the rater (that of observer or simulated patient) influenced the rating. Using a nested study design, 24 physical therapy students were assessed by eight raters. The raters were randomly and equally assigned to four teams. Each team assessed six students. One rater acted as the simulated patient for the first three students in each group, and the other rater acted as observer. This order was reversed for the last three students. Each student performed nine mini-diagnostic patient cases consisting of three diagnostic probes reproduced at three different anatomical sites. The results demonstrate that 1) similar diagnostic concepts can be generalized across anatomical sites, although different concepts or skills cannot be generalized at a given anatomical site or across sites; 2) interrater reliability was excellent; and 3) the status of the raters (ie, simulated patient or observer) did not bias the ratings.(ABSTRACT TRUNCATED AT 250 WORDS)

Cost effectiveness of prostacyclins in pulmonary arterial hypertension.

PubMed

Roman, Antonio; Barberà, Joan A; Escribano, Pilar; Sala, Maria L; Febrer, Laia; Oyagüez, Itziar; Sabater, Eliazar; Casado, Miguel A

2012-05-01

Pulmonary arterial hypertension (PAH) is considered an orphan disease. Prostacyclins are the keystone for PAH treatment. Choosing between the three available prostacyclin therapies could be complicated because there are no comparison studies, so the final decision must be driven by factors such as efficacy, administration route, safety profile and economic aspects. This study provides a cost-effectiveness and cost-utility comparison of initiating prostacyclin therapy with three different treatment alternatives (inhaled iloprost [ILO], intravenous epoprostenol [EPO] and subcutaneous treprostinil [TRE]) for patients with PAH. The goal of this work is to help physicians with their therapeutic decision-making. A Markov model was built to simulate a patient cohort with class III PAH according to the classification of the New York Heart Association (NYHA). Four health states corresponding with the NYHA classes plus death were allowed for patients in the model. Changing the treatment was possible when patients worsened from functional class III to IV. The time horizon was 3 years, allowing patients to transition between health states on a 12-week cycle basis. The study perspective was that of the National Health System (NHS) [only direct medical costs were included]. Unitary costs were obtained from the Drug Catalogue and e-Salud Database in 2009 and are given in euros (€). Data on health resources and treatment pathways were informed by a four-member expert panel. Efficacy was obtained from pivotal clinical trials of ILO, EPO and TRE, the latter used in Spain as a foreign medication. Utilities for each health state were obtained from the literature. The final efficacy measure was life-years gained (LYG), and utilities were used to obtain quality-adjusted life-years (QALYs). Costs and effects were discounted at a 3% rate. To check for the robustness of the results, sensitivity analyses were performed. At the end of the 3 years, in the base case of the deterministic analysis, initiating prostacyclin therapy with iloprost was the less costly strategy (€132,840), followed by treprostinil (€359,869) and epoprostenol (€429,775). Epoprostenol has shown the best efficacy results with 2.73 LYG and 1.78 QALY, followed by iloprost (2.69 LYG and 1.74 QALY) and treprostinil (2.69 LYG and 1.73 QALY). Incremental cost-effectiveness ratios (ICER) and cost-utility ratios (ICUR) of epoprostenol versus iloprost and treprostinil were much above the €30,000 per LYG or QALY threshold commonly used in Spain. Iloprost was dominant compared with treprostinil. In the probabilistic analysis, epoprostenol, when compared with iloprost, was a dominant strategy in 15% of the simulations, but it was not a cost-effective option in 83% of the cases. When compared with treprostinil, epoprostenol was dominant in 43% of the simulations. Iloprost was dominant compared with treprostinil in 45% of the cases and it was a cost-effective alternative in 39% of the simulations. Initiating prostacyclin treatment with iloprost in patients with PAH, functional class III of the NYHA, is the less costly alternative for the NHS in Spain, with a good efficacy profile when compared with the other alternatives.

Virtual patient simulation in psychiatric care - A pilot study of digital support for collaborate learning.

PubMed

Sunnqvist, Charlotta; Karlsson, Karin; Lindell, Lisbeth; Fors, Uno

2016-03-01

Psychiatric and mental health nursing is built on a trusted nurse and patient relationship. Therefore communication and clinical reasoning are two important issues. Our experiences as teachers in psychiatric educational programmes are that the students feel anxiety and fear before they start their clinical practices in psychiatry. Therefore there is a need for bridging over the fear. Technology enhanced learning might support such activities so we used Virtual patients (VPs), an interactive computer simulations of real-life clinical scenarios. The aim of this study was to investigate 4th term nursing students' opinions on the use of Virtual Patients for assessment in a Mental Health and Ill-health course module. We asked 24 volunteering students to practise with five different VP cases during almost 10 weeks before the exam. The participants were gathered together for participating in a written and an oral evaluation. The students were positive to the use of VPs in psychiatry and were very positive to use VPs in their continued nursing education. It seems that Virtual Patients can be an activity producing pedagogic model promoting students' independent knowledge development, critical thinking, reflection and problem solving ability for nurse students in psychiatric care. Copyright © 2016 Elsevier Ltd. All rights reserved.