Sample records for diagnostic yield interpretation
-
Comparing diagnostic tests on benefit-risk.
Pennello, Gene; Pantoja-Galicia, Norberto; Evans, Scott
2016-01-01
Comparing diagnostic tests on accuracy alone can be inconclusive. For example, a test may have better sensitivity than another test yet worse specificity. Comparing tests on benefit risk may be more conclusive because clinical consequences of diagnostic error are considered. For benefit-risk evaluation, we propose diagnostic yield, the expected distribution of subjects with true positive, false positive, true negative, and false negative test results in a hypothetical population. We construct a table of diagnostic yield that includes the number of false positive subjects experiencing adverse consequences from unnecessary work-up. We then develop a decision theory for evaluating tests. The theory provides additional interpretation to quantities in the diagnostic yield table. It also indicates that the expected utility of a test relative to a perfect test is a weighted accuracy measure, the average of sensitivity and specificity weighted for prevalence and relative importance of false positive and false negative testing errors, also interpretable as the cost-benefit ratio of treating non-diseased and diseased subjects. We propose plots of diagnostic yield, weighted accuracy, and relative net benefit of tests as functions of prevalence or cost-benefit ratio. Concepts are illustrated with hypothetical screening tests for colorectal cancer with test positive subjects being referred to colonoscopy.
-
Aihara, Hiroyuki; Kumar, Nitin; Thompson, Christopher C
2018-04-19
An education system for narrow band imaging (NBI) interpretation requires sufficient exposure to key features. However, access to didactic lectures by experienced teachers is limited in the United States. To develop and assess the effectiveness of a colorectal lesion identification tutorial. In the image analysis pretest, subjects including 9 experts and 8 trainees interpreted 50 white light (WL) and 50 NBI images of colorectal lesions. Results were not reviewed with subjects. Trainees then participated in an online tutorial emphasizing NBI interpretation in colorectal lesion analysis. A post-test was administered and diagnostic yields were compared to pre-education diagnostic yields. Under the NBI mode, experts showed higher diagnostic yields (sensitivity 91.5% [87.3-94.4], specificity 90.6% [85.1-94.2], and accuracy 91.1% [88.5-93.7] with substantial interobserver agreement [κ value 0.71]) compared to trainees (sensitivity 89.6% [84.8-93.0], specificity 80.6% [73.5-86.3], and accuracy 86.0% [82.6-89.2], with substantial interobserver agreement [κ value 0.69]). The online tutorial improved the diagnostic yields of trainees to the equivalent level of experts (sensitivity 94.1% [90.0-96.6], specificity 89.0% [83.0-93.2], and accuracy 92.0% [89.3-94.7], p < 0.001 with substantial interobserver agreement [κ value 0.78]). This short, online tutorial improved diagnostic performance and interobserver agreement. © 2018 S. Karger AG, Basel.
-
Feeney, Daniel A; Ober, Christopher P; Snyder, Laura A; Hill, Sara A; Jessen, Carl R
2013-01-01
Peritoneal, mesenteric, and omental diseases are important causes of morbidity and mortality in humans and animals, although information in the veterinary literature is limited. The purposes of this retrospective study were to determine whether objectively applied ultrasound interpretive criteria are statistically useful in differentiating among cytologically defined normal, inflammatory, and neoplastic peritoneal conditions in dogs and cats. A second goal was to determine the cytologically interpretable yield on ultrasound-guided, fine-needle sampling of peritoneal, mesenteric, or omental structures. Sonographic criteria agreed upon by the authors were retrospectively and independently applied by two radiologists to the available ultrasound images without knowledge of the cytologic diagnosis and statistically compared to the ultrasound-guided, fine-needle aspiration cytologic interpretations. A total of 72 dogs and 49 cats with abdominal peritoneal, mesenteric, or omental (peritoneal) surface or effusive disease and 17 dogs and 3 cats with no cytologic evidence of inflammation or neoplasia were included. The optimized, ultrasound criteria-based statistical model created independently for each radiologist yielded an equation-based diagnostic category placement accuracy of 63.2-69.9% across the two involved radiologists. Regional organ-associated masses or nodules as well as aggregated bowel and peritoneal thickening were more associated with peritoneal neoplasia whereas localized, severely complex fluid collections were more associated with inflammatory peritoneal disease. The cytologically interpretable yield for ultrasound-guided fine-needle sampling was 72.3% with no difference between species, making this a worthwhile clinical procedure. © 2013 Veterinary Radiology & Ultrasound.
-
X-ray power and yield measurements at the refurbished Z machine
Jones, M. C.; Ampleford, D. J.; Cuneo, M. E.; ...
2014-08-04
Advancements have been made in the diagnostic techniques to measure accurately the total radiated x-ray yield and power from z-pinch loads at the Z Machine with high accuracy. The Z-accelerator is capable of outputting 2MJ and 330 TW of x-ray yield and power, and accurately measuring these quantities is imperative. We will describe work over the past several years which include the development of new diagnostics, improvements to existing diagnostics, and implementation of automated data analysis routines. A set of experiments were conducted on the Z machine where the load and machine configuration were held constant. During this shot series,more » it was observed that total z-pinch x-ray emission power determined from the two common techniques for inferring the x-ray power, Kimfol filtered x-ray diode diagnostic and the Total Power and Energy diagnostic gave 450 TW and 327 TW respectively. Our analysis shows the latter to be the more accurate interpretation. More broadly, the comparison demonstrates the necessity to consider spectral response and field of view when inferring xray powers from z-pinch sources.« less
-
Autoadaptivity and optimization in distributed ECG interpretation.
Augustyniak, Piotr
2010-03-01
This paper addresses principal issues of the ECG interpretation adaptivity in a distributed surveillance network. In the age of pervasive access to wireless digital communication, distributed biosignal interpretation networks may not only optimally solve difficult medical cases, but also adapt the data acquisition, interpretation, and transmission to the variable patient's status and availability of technical resources. The background of such adaptivity is the innovative use of results from the automatic ECG analysis to the seamless remote modification of the interpreting software. Since the medical relevance of issued diagnostic data depends on the patient's status, the interpretation adaptivity implies the flexibility of report content and frequency. Proposed solutions are based on the research on human experts behavior, procedures reliability, and usage statistics. Despite the limited scale of our prototype client-server application, the tests yielded very promising results: the transmission channel occupation was reduced by 2.6 to 5.6 times comparing to the rigid reporting mode and the improvement of the remotely computed diagnostic outcome was achieved in case of over 80% of software adaptation attempts.
-
Effect of Radiologists’ Diagnostic Work-up Volume on Interpretive Performance
Anderson, Melissa L.; Smith, Robert A.; Carney, Patricia A.; Miglioretti, Diana L.; Monsees, Barbara S.; Sickles, Edward A.; Taplin, Stephen H.; Geller, Berta M.; Yankaskas, Bonnie C.; Onega, Tracy L.
2014-01-01
Purpose To examine radiologists’ screening performance in relation to the number of diagnostic work-ups performed after abnormal findings are discovered at screening mammography by the same radiologist or by different radiologists. Materials and Methods In an institutional review board–approved HIPAA-compliant study, the authors linked 651 671 screening mammograms interpreted from 2002 to 2006 by 96 radiologists in the Breast Cancer Surveillance Consortium to cancer registries (standard of reference) to evaluate the performance of screening mammography (sensitivity, false-positive rate [FPRfalse-positive rate], and cancer detection rate [CDRcancer detection rate]). Logistic regression was used to assess the association between the volume of recalled screening mammograms (“own” mammograms, where the radiologist who interpreted the diagnostic image was the same radiologist who had interpreted the screening image, and “any” mammograms, where the radiologist who interpreted the diagnostic image may or may not have been the radiologist who interpreted the screening image) and screening performance and whether the association between total annual volume and performance differed according to the volume of diagnostic work-up. Results Annually, 38% of radiologists performed the diagnostic work-up for 25 or fewer of their own recalled screening mammograms, 24% performed the work-up for 0–50, and 39% performed the work-up for more than 50. For the work-up of recalled screening mammograms from any radiologist, 24% of radiologists performed the work-up for 0–50 mammograms, 32% performed the work-up for 51–125, and 44% performed the work-up for more than 125. With increasing numbers of radiologist work-ups for their own recalled mammograms, the sensitivity (P = .039), FPRfalse-positive rate (P = .004), and CDRcancer detection rate (P < .001) of screening mammography increased, yielding a stepped increase in women recalled per cancer detected from 17.4 for 25 or fewer mammograms to 24.6 for more than 50 mammograms. Increases in work-ups for any radiologist yielded significant increases in FPRfalse-positive rate (P = .011) and CDRcancer detection rate (P = .001) and a nonsignificant increase in sensitivity (P = .15). Radiologists with a lower annual volume of any work-ups had consistently lower FPRfalse-positive rate, sensitivity, and CDRcancer detection rate at all annual interpretive volumes. Conclusion These findings support the hypothesis that radiologists may improve their screening performance by performing the diagnostic work-up for their own recalled screening mammograms and directly receiving feedback afforded by means of the outcomes associated with their initial decision to recall. Arranging for radiologists to work up a minimum number of their own recalled cases could improve screening performance but would need systems to facilitate this workflow. © RSNA, 2014 Online supplemental material is available for this article. PMID:24960110
-
Effect of radiologists' diagnostic work-up volume on interpretive performance.
Buist, Diana S M; Anderson, Melissa L; Smith, Robert A; Carney, Patricia A; Miglioretti, Diana L; Monsees, Barbara S; Sickles, Edward A; Taplin, Stephen H; Geller, Berta M; Yankaskas, Bonnie C; Onega, Tracy L
2014-11-01
To examine radiologists' screening performance in relation to the number of diagnostic work-ups performed after abnormal findings are discovered at screening mammography by the same radiologist or by different radiologists. In an institutional review board-approved HIPAA-compliant study, the authors linked 651 671 screening mammograms interpreted from 2002 to 2006 by 96 radiologists in the Breast Cancer Surveillance Consortium to cancer registries (standard of reference) to evaluate the performance of screening mammography (sensitivity, false-positive rate [ FPR false-positive rate ], and cancer detection rate [ CDR cancer detection rate ]). Logistic regression was used to assess the association between the volume of recalled screening mammograms ("own" mammograms, where the radiologist who interpreted the diagnostic image was the same radiologist who had interpreted the screening image, and "any" mammograms, where the radiologist who interpreted the diagnostic image may or may not have been the radiologist who interpreted the screening image) and screening performance and whether the association between total annual volume and performance differed according to the volume of diagnostic work-up. Annually, 38% of radiologists performed the diagnostic work-up for 25 or fewer of their own recalled screening mammograms, 24% performed the work-up for 0-50, and 39% performed the work-up for more than 50. For the work-up of recalled screening mammograms from any radiologist, 24% of radiologists performed the work-up for 0-50 mammograms, 32% performed the work-up for 51-125, and 44% performed the work-up for more than 125. With increasing numbers of radiologist work-ups for their own recalled mammograms, the sensitivity (P = .039), FPR false-positive rate (P = .004), and CDR cancer detection rate (P < .001) of screening mammography increased, yielding a stepped increase in women recalled per cancer detected from 17.4 for 25 or fewer mammograms to 24.6 for more than 50 mammograms. Increases in work-ups for any radiologist yielded significant increases in FPR false-positive rate (P = .011) and CDR cancer detection rate (P = .001) and a nonsignificant increase in sensitivity (P = .15). Radiologists with a lower annual volume of any work-ups had consistently lower FPR false-positive rate , sensitivity, and CDR cancer detection rate at all annual interpretive volumes. These findings support the hypothesis that radiologists may improve their screening performance by performing the diagnostic work-up for their own recalled screening mammograms and directly receiving feedback afforded by means of the outcomes associated with their initial decision to recall. Arranging for radiologists to work up a minimum number of their own recalled cases could improve screening performance but would need systems to facilitate this workflow.
-
The rapid evolution of molecular genetic diagnostics in neuromuscular diseases.
Volk, Alexander E; Kubisch, Christian
2017-10-01
The development of massively parallel sequencing (MPS) has revolutionized molecular genetic diagnostics in monogenic disorders. The present review gives a brief overview of different MPS-based approaches used in clinical diagnostics of neuromuscular disorders (NMDs) and highlights their advantages and limitations. MPS-based approaches like gene panel sequencing, (whole) exome sequencing, (whole) genome sequencing, and RNA sequencing have been used to identify the genetic cause in NMDs. Although gene panel sequencing has evolved as a standard test for heterogeneous diseases, it is still debated, mainly because of financial issues and unsolved problems of variant interpretation, whether genome sequencing (and to a lesser extent also exome sequencing) of single patients can already be regarded as routine diagnostics. However, it has been shown that the inclusion of parents and additional family members often leads to a substantial increase in the diagnostic yield in exome-wide/genome-wide MPS approaches. In addition, MPS-based RNA sequencing just enters the research and diagnostic scene. Next-generation sequencing increasingly enables the detection of the genetic cause in highly heterogeneous diseases like NMDs in an efficient and affordable way. Gene panel sequencing and family-based exome sequencing have been proven as potent and cost-efficient diagnostic tools. Although clinical validation and interpretation of genome sequencing is still challenging, diagnostic RNA sequencing represents a promising tool to bypass some hurdles of diagnostics using genomic DNA.
-
Helbig, Katherine L; Farwell Hagman, Kelly D; Shinde, Deepali N; Mroske, Cameron; Powis, Zöe; Li, Shuwei; Tang, Sha; Helbig, Ingo
2016-09-01
To assess the yield of diagnostic exome sequencing (DES) and to characterize the molecular findings in characterized and novel disease genes in patients with epilepsy. In an unselected sample of 1,131 patients referred for DES, overall results were compared between patients with and without epilepsy. DES results were examined based on age of onset and epilepsy diagnosis. Positive/likely positive results were identified in 112/293 (38.2%) epilepsy patients compared with 210/732 (28.7%) patients without epilepsy (P = 0.004). The diagnostic yield in characterized disease genes among patients with epilepsy was 33.4% (105/314). KCNQ2, MECP2, FOXG1, IQSEC2, KMT2A, and STXBP1 were most commonly affected by de novo alterations. Patients with epileptic encephalopathies had the highest rate of positive findings (43.4%). A likely positive novel genetic etiology was proposed in 14/200 (7%) patients with epilepsy; this frequency was highest in patients with epileptic encephalopathies (17%). Three genes (COQ4, DNM1, and PURA) were initially reported as likely positive novel disease genes and were subsequently corroborated in independent peer-reviewed publications. DES with analysis and interpretation of both characterized and novel genetic etiologies is a useful diagnostic tool in epilepsy, particularly in severe early-onset epilepsy. The reporting on novel genetic etiologies may further increase the diagnostic yield.Genet Med 18 9, 898-905.
-
A readers' guide to the interpretation of diagnostic test properties: clinical example of sepsis.
Fischer, Joachim E; Bachmann, Lucas M; Jaeschke, Roman
2003-07-01
One of the most challenging practical and daily problems in intensive care medicine is the interpretation of the results from diagnostic tests. In neonatology and pediatric intensive care the early diagnosis of potentially life-threatening infections is a particularly important issue. A plethora of tests have been suggested to improve diagnostic decision making in the clinical setting of infection which is a clinical example used in this article. Several criteria that are critical to evidence-based appraisal of published data are often not adhered to during the study or in reporting. To enhance the critical appraisal on articles on diagnostic tests we discuss various measures of test accuracy: sensitivity, specificity, receiver operating characteristic curves, positive and negative predictive values, likelihood ratios, pretest probability, posttest probability, and diagnostic odds ratio. We suggest the following minimal requirements for reporting on the diagnostic accuracy of tests: a plot of the raw data, multilevel likelihood ratios, the area under the receiver operating characteristic curve, and the cutoff yielding the highest discriminative ability. For critical appraisal it is mandatory to report confidence intervals for each of these measures. Moreover, to allow comparison to the readers' patient population authors should provide data on study population characteristics, in particular on the spectrum of diseases and illness severity.
-
Chandler, Natalie; Best, Sunayna; Hayward, Jane; Faravelli, Francesca; Mansour, Sahar; Kivuva, Emma; Tapon, Dagmar; Male, Alison; DeVile, Catherine; Chitty, Lyn S
2018-03-29
PurposeUnexpected fetal abnormalities occur in 2-5% of pregnancies. While traditional cytogenetic and microarray approaches achieve diagnosis in around 40% of cases, lack of diagnosis in others impedes parental counseling, informed decision making, and pregnancy management. Postnatally exome sequencing yields high diagnostic rates, but relies on careful phenotyping to interpret genotype results. Here we used a multidisciplinary approach to explore the utility of rapid fetal exome sequencing for prenatal diagnosis using skeletal dysplasias as an exemplar.MethodsParents in pregnancies undergoing invasive testing because of sonographic fetal abnormalities, where multidisciplinary review considered skeletal dysplasia a likely etiology, were consented for exome trio sequencing (both parents and fetus). Variant interpretation focused on a virtual panel of 240 genes known to cause skeletal dysplasias.ResultsDefinitive molecular diagnosis was made in 13/16 (81%) cases. In some cases, fetal ultrasound findings alone were of sufficient severity for parents to opt for termination. In others, molecular diagnosis informed accurate prediction of outcome, improved parental counseling, and enabled parents to terminate or continue the pregnancy with certainty.ConclusionTrio sequencing with expert multidisciplinary review for case selection and data interpretation yields timely, high diagnostic rates in fetuses presenting with unexpected skeletal abnormalities. This improves parental counseling and pregnancy management.Genetics in Medicine advance online publication, 29 March 2018; doi:10.1038/gim.2018.30.
-
The role of molecular genetic analysis in the diagnosis of primary ciliary dyskinesia.
Kim, Raymond H; A Hall, David; Cutz, Ernest; Knowles, Michael R; Nelligan, Kathleen A; Nykamp, Keith; Zariwala, Maimoona A; Dell, Sharon D
2014-03-01
Primary ciliary dyskinesia (PCD) is an autosomal recessive genetic disorder of motile cilia. The diagnosis of PCD has previously relied on ciliary analysis with transmission electron microscopy or video microscopy. However, patients with PCD may have normal ultrastructural appearance, and ciliary analysis has limited accessibility. Alternatively, PCD can be diagnosed by demonstrating biallelic mutations in known PCD genes. Genetic testing is emerging as a diagnostic tool to complement ciliary analysis where interpretation and access may delay diagnosis. To determine the diagnostic yield of genetic testing of patients with a confirmed or suspected diagnosis of PCD in a multiethnic urban center. Twenty-eight individuals with confirmed PCD on transmission electron microscopy of ciliary ultrastructure and 24 individuals with a probable diagnosis of PCD based on a classical PCD phenotype and low nasal nitric oxide had molecular analysis of 12 genes associated with PCD. Of 49 subjects who underwent ciliary biopsy, 28 (57%) were diagnosed with PCD through an ultrastructural defect. Of the 52 individuals who underwent molecular genetic analysis, 22 (42%) individuals had two mutations in known PCD genes. Twenty-four previously unreported mutations in known PCD genes were observed. Combining both diagnostic modalities of biopsy and molecular genetics, the diagnostic yield increased to 69% compared with 57% based on biopsy alone. The diagnosis of PCD is challenging and has traditionally relied on ciliary biopsy, which is unreliable as the sole criterion for a definitive diagnosis. Molecular genetic analysis can be used as a complementary test to increase the diagnostic yield.
-
Code of Federal Regulations, 2011 CFR
2011-10-01
... interpretation of diagnostic radiology and other diagnostic tests. 415.180 Section 415.180 Public Health CENTERS... for the interpretation of diagnostic radiology and other diagnostic tests. (a) General rule. Physician fee schedule payment is made for the interpretation of diagnostic radiology and other diagnostic tests...
-
Code of Federal Regulations, 2010 CFR
2010-10-01
... interpretation of diagnostic radiology and other diagnostic tests. 415.180 Section 415.180 Public Health CENTERS... for the interpretation of diagnostic radiology and other diagnostic tests. (a) General rule. Physician fee schedule payment is made for the interpretation of diagnostic radiology and other diagnostic tests...
-
Two-dimensional interpreter for field-reversed configurations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steinhauer, Loren, E-mail: lstein@uw.edu
2014-08-15
An interpretive method is developed for extracting details of the fully two-dimensional (2D) “internal” structure of field-reversed configurations (FRC) from common diagnostics. The challenge is that only external and “gross” diagnostics are routinely available in FRC experiments. Inferring such critical quantities as the poloidal flux and the particle inventory has commonly relied on a theoretical construct based on a quasi-one-dimensional approximation. Such inferences sometimes differ markedly from the more accurate, fully 2D reconstructions of equilibria. An interpreter based on a fully 2D reconstruction is needed to enable realistic within-the-shot tracking of evolving equilibrium properties. Presented here is a flexible equilibriummore » reconstruction with which an extensive data base of equilibria was constructed. An automated interpreter then uses this data base as a look-up table to extract evolving properties. This tool is applied to data from the FRC facility at Tri Alpha Energy. It yields surprising results at several points, such as the inferences that the local β (plasma pressure/external magnetic pressure) of the plasma climbs well above unity and the poloidal flux loss time is somewhat longer than previously thought, both of which arise from full two-dimensionality of FRCs.« less
-
Magnetic resonance imaging for the ophthalmologist: A primer
Simha, Arathi; Irodi, Aparna; David, Sarada
2012-01-01
Magnetic resonance imaging (MRI) and computerized tomography (CT) have added a new dimension in the diagnosis and management of ocular and orbital diseases. Although CT is more widely used, MRI is the modality of choice in select conditions and can be complimentary to CT in certain situations. The diagnostic yield is best when the ophthalmologist and radiologist work together. Ophthalmologists should be able to interpret these complex imaging modalities as better clinical correlation is then possible. In this article, we attempt to describe the basic principles of MRI and its interpretation, avoiding confusing technical terms. PMID:22824600
-
Prohászka, Zoltán
2008-07-06
Haemolytic uremic syndrome and thrombotic thrombocytopenic purpura are overlapping clinical entities based on historical classification. Recent developments in the unfolding of the pathomechanisms of these diseases resulted in the creation of a molecular etiology-based classification. Understanding of some causative relationships yielded detailed diagnostic approaches, novel therapeutic options and thorough prognostic assortment of the patients. Although haemolytic uremic syndrome and thrombotic thrombocytopenic purpura are rare diseases with poor prognosis, the precise molecular etiology-based diagnosis might properly direct the therapy of the affected patients. The current review focuses on the theoretical background and detailed description of the available diagnostic possibilities, and some practical information necessary for the interpretation of their results.
-
Natriuretic peptides: Diagnostic and therapeutic use
Pandit, Kaushik; Mukhopadhyay, Pradip; Ghosh, Sujoy; Chowdhury, Subhankar
2011-01-01
Natriuretic peptides (NPs) are hormones which are mainly secreted from heart and have important natriuretic and kaliuretic properties. There are four different groups NPs identified till date [atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), C-type natriuretic peptide (CNP) and dendroaspis natriuretic peptide, a D-type natriuretic peptide (DNP)], each with its own characteristic functions. The N-terminal part of the prohormone of BNP, NT-proBNP, is secreted alongside BNP and has been documented to have important diagnostic value in heart failure. NPs or their fragments have been subjected to scientific observation for their diagnostic value and this has yielded important epidemiological data for interpretation. However, little progress has been made in harnessing the therapeutic potential of these cardiac hormones. PMID:22145138
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Koeylue, U.O.
1997-05-01
An in situ particulate diagnostic/analysis technique is outlined based on the Rayleigh-Debye-Gans polydisperse fractal aggregate (RDG/PFA) scattering interpretation of absolute angular light scattering and extinction measurements. Using proper particle refractive index, the proposed data analysis method can quantitatively yield all aggregate parameters (particle volume fraction, f{sub v}, fractal dimension, D{sub f}, primary particle diameter, d{sub p}, particle number density, n{sub p}, and aggregate size distribution, pdf(N)) without any prior knowledge about the particle-laden environment. The present optical diagnostic/interpretation technique was applied to two different soot-containing laminar and turbulent ethylene/air nonpremixed flames in order to assess its reliability. The aggregate interpretationmore » of optical measurements yielded D{sub f}, d{sub p}, and pdf(N) that are in excellent agreement with ex situ thermophoretic sampling/transmission electron microscope (TS/TEM) observations within experimental uncertainties. However, volume-equivalent single particle models (Rayleigh/Mie) overestimated d{sub p} by about a factor of 3, causing an order of magnitude underestimation in n{sub p}. Consequently, soot surface areas and growth rates were in error by a factor of 3, emphasizing that aggregation effects need to be taken into account when using optical diagnostics for a reliable understanding of soot formation/evolution mechanism in flames. The results also indicated that total soot emissivities were generally underestimated using Rayleigh analysis (up to 50%), mainly due to the uncertainties in soot refractive indices at infrared wavelengths. This suggests that aggregate considerations may not be essential for reasonable radiation heat transfer predictions from luminous flames because of fortuitous error cancellation, resulting in typically a 10 to 30% net effect.« less
-
Riedel thyroiditis: Fine needle aspiration findings of a rare entity.
Weidner, Anna-Sophie; Molina, David; DeSimone, Robert A; Cohen, Marc A; Giorgadze, Tamar; Scognamiglio, Theresa; Hoda, Rana S
2015-09-01
Riedel thyroiditis is a rare fibrosing disorder characterized by extension of the fibroinflammatory process beyond the thyroid capsule. Due to the nature of this lesion, fine-needle aspiration often yields scant material and may be interpreted as non-diagnostic. In this report, we describe cytologic features that allow the cytopathologist to favor a diagnosis of Riedel thyroiditis, thereby guiding appropriate further work-up and management. © 2015 Wiley Periodicals, Inc.
-
Fault diagnosis model for power transformers based on information fusion
NASA Astrophysics Data System (ADS)
Dong, Ming; Yan, Zhang; Yang, Li; Judd, Martin D.
2005-07-01
Methods used to assess the insulation status of power transformers before they deteriorate to a critical state include dissolved gas analysis (DGA), partial discharge (PD) detection and transfer function techniques, etc. All of these approaches require experience in order to correctly interpret the observations. Artificial intelligence (AI) is increasingly used to improve interpretation of the individual datasets. However, a satisfactory diagnosis may not be obtained if only one technique is used. For example, the exact location of PD cannot be predicted if only DGA is performed. However, using diverse methods may result in different diagnosis solutions, a problem that is addressed in this paper through the introduction of a fuzzy information infusion model. An inference scheme is proposed that yields consistent conclusions and manages the inherent uncertainty in the various methods. With the aid of information fusion, a framework is established that allows different diagnostic tools to be combined in a systematic way. The application of information fusion technique for insulation diagnostics of transformers is proved promising by means of examples.
-
Novotny, Tomas; Bond, Raymond; Andrsova, Irena; Koc, Lumir; Sisakova, Martina; Finlay, Dewar; Guldenring, Daniel; Spinar, Jindrich; Malik, Marek
2017-05-01
Most contemporary 12-lead electrocardiogram (ECG) devices offer computerized diagnostic proposals. The reliability of these automated diagnoses is limited. It has been suggested that incorrect computer advice can influence physician decision-making. This study analyzed the role of diagnostic proposals in the decision process by a group of fellows of cardiology and other internal medicine subspecialties. A set of 100 clinical 12-lead ECG tracings was selected covering both normal cases and common abnormalities. A team of 15 junior Cardiology Fellows and 15 Non-Cardiology Fellows interpreted the ECGs in 3 phases: without any diagnostic proposal, with a single diagnostic proposal (half of them intentionally incorrect), and with four diagnostic proposals (only one of them being correct) for each ECG. Self-rated confidence of each interpretation was collected. Availability of diagnostic proposals significantly increased the diagnostic accuracy (p<0.001). Nevertheless, in case of a single proposal (either correct or incorrect) the increase of accuracy was present in interpretations with correct diagnostic proposals, while the accuracy was substantially reduced with incorrect proposals. Confidence levels poorly correlated with interpretation scores (rho≈2, p<0.001). Logistic regression showed that an interpreter is most likely to be correct when the ECG offers a correct diagnostic proposal (OR=10.87) or multiple proposals (OR=4.43). Diagnostic proposals affect the diagnostic accuracy of ECG interpretations. The accuracy is significantly influenced especially when a single diagnostic proposal (either correct or incorrect) is provided. The study suggests that the presentation of multiple computerized diagnoses is likely to improve the diagnostic accuracy of interpreters. Copyright © 2017 Elsevier B.V. All rights reserved.
-
Bespamyatnov, Igor O; Rowan, William L; Granetz, Robert S
2008-10-01
Charge exchange recombination spectroscopy on Alcator C-Mod relies on the use of the diagnostic neutral beam injector as a source of neutral particles which penetrate deep into the plasma. It employs the emission resulting from the interaction of the beam atoms with fully ionized impurity ions. To interpret the emission from a given point in the plasma as the density of emitting impurity ions, the density of beam atoms must be known. Here, an analysis of beam propagation is described which yields the beam density profile throughout the beam trajectory from the neutral beam injector to the core of the plasma. The analysis includes the effects of beam formation, attenuation in the neutral gas surrounding the plasma, and attenuation in the plasma. In the course of this work, a numerical simulation and an analytical approximation for beam divergence are developed. The description is made sufficiently compact to yield accurate results in a time consistent with between-shot analysis.
-
Oneda, Beatrice; Baldinger, Rosa; Reissmann, Regina; Reshetnikova, Irina; Krejci, Pavel; Masood, Rahim; Ochsenbein-Kölble, Nicole; Bartholdi, Deborah; Steindl, Katharina; Morotti, Denise; Faranda, Marzia; Baumer, Alessandra; Asadollahi, Reza; Joset, Pascal; Niedrist, Dunja; Breymann, Christian; Hebisch, Gundula; Hüsler, Margaret; Mueller, René; Prentl, Elke; Wisser, Josef; Zimmermann, Roland; Rauch, Anita
2014-06-01
The objective of this study was to determine for the first time the reliability and the diagnostic power of high-resolution microarray testing in routine prenatal diagnostics. We applied high-resolution chromosomal microarray testing in 464 cytogenetically normal prenatal samples with any indication for invasive testing. High-resolution testing revealed a diagnostic yield of 6.9% and 1.6% in cases of fetal ultrasound anomalies and cases of advanced maternal age (AMA), respectively, which is similar to previous studies using low-resolution microarrays. In three (0.6%) additional cases with an indication of AMA, an aberration in susceptibility risk loci was detected. Moreover, one case (0.2%) showed an X-linked aberration in a female fetus, a finding relevant for future family planning. We found the rate of cases, in which the parents had to be tested for interpretation of unreported copy number variants (3.7%), and the rate of remaining variants of unknown significance (0.4%) acceptably low. Of note, these findings did not cause termination of pregnancy after expert genetic counseling. The 0.4% rate of confined placental mosaicism was similar to that observed by conventional karyotyping and notably involved a case of placental microdeletion. High-resolution prenatal microarray testing is a reliable technique that increases diagnostic yield by at least 17.3% when compared with conventional karyotyping, without an increase in the frequency of variants of uncertain significance. © 2014 John Wiley & Sons, Ltd.
-
Diagnostic Performance of Electronic Syndromic Surveillance Systems in Acute Care
Kashiouris, M.; O’Horo, J.C.; Pickering, B.W.; Herasevich, V.
2013-01-01
Context Healthcare Electronic Syndromic Surveillance (ESS) is the systematic collection, analysis and interpretation of ongoing clinical data with subsequent dissemination of results, which aid clinical decision-making. Objective To evaluate, classify and analyze the diagnostic performance, strengths and limitations of existing acute care ESS systems. Data Sources All available to us studies in Ovid MEDLINE, Ovid EMBASE, CINAHL and Scopus databases, from as early as January 1972 through the first week of September 2012. Study Selection: Prospective and retrospective trials, examining the diagnostic performance of inpatient ESS and providing objective diagnostic data including sensitivity, specificity, positive and negative predictive values. Data Extraction Two independent reviewers extracted diagnostic performance data on ESS systems, including clinical area, number of decision points, sensitivity and specificity. Positive and negative likelihood ratios were calculated for each healthcare ESS system. A likelihood matrix summarizing the various ESS systems performance was created. Results The described search strategy yielded 1639 articles. Of these, 1497 were excluded on abstract information. After full text review, abstraction and arbitration with a third reviewer, 33 studies met inclusion criteria, reporting 102,611 ESS decision points. The yielded I2 was high (98.8%), precluding meta-analysis. Performance was variable, with sensitivities ranging from 21% –100% and specificities ranging from 5%-100%. Conclusions There is significant heterogeneity in the diagnostic performance of the available ESS implements in acute care, stemming from the wide spectrum of different clinical entities and ESS systems. Based on the results, we introduce a conceptual framework using a likelihood ratio matrix for evaluation and meaningful application of future, frontline clinical decision support systems. PMID:23874359
-
Shriberg, Lawrence D; Strand, Edythe A; Fourakis, Marios; Jakielski, Kathy J; Hall, Sheryl D; Karlsson, Heather B; Mabie, Heather L; McSweeny, Jane L; Tilkens, Christie M; Wilson, David L
2017-04-14
The purpose of this 2nd article in this supplement is to report validity support findings for the Pause Marker (PM), a proposed single-sign diagnostic marker of childhood apraxia of speech (CAS). PM scores and additional perceptual and acoustic measures were obtained from 296 participants in cohorts with idiopathic and neurogenetic CAS, adult-onset apraxia of speech and primary progressive apraxia of speech, and idiopathic speech delay. Adjusted for questionable specificity disagreements with a pediatric Mayo Clinic diagnostic standard, the estimated sensitivity and specificity, respectively, of the PM were 86.8% and 100% for the CAS cohort, yielding positive and negative likelihood ratios of 56.45 (95% confidence interval [CI]: [1.15, 2763.31]) and 0.13 (95% CI [0.06, 0.30]). Specificity of the PM for 4 cohorts totaling 205 participants with speech delay was 98.5%. These findings are interpreted as providing support for the PM as a near-conclusive diagnostic marker of CAS.
-
NASA Technical Reports Server (NTRS)
Lee, Timothy J.; Head-Gordon, Martin; Rendell, Alistair P.; Langhoff, Stephen R. (Technical Monitor)
1995-01-01
A diagnostic for perturbation theory calculations, S(sub 2), is defined and numerical results are compared to the established T(sub 1) diagnostic from coupled-cluster theory. S(sub 2) is the lowest order non-zero contribution to a perturbation expansion of T(sub 1). S(sub 2) is a reasonable estimate of the importance of non-dynamical electron correlation, although not as reliable as T(sub 1). S(sub 2) values less than or equal to 0.012 suggest that low orders of perturbation theory should yield reasonable results; S(sub 2) values between 0.012-0.015 suggest that caution is required in interpreting results from low orders of perturbation theory; S(sub 2) values greater than or equal to 0.015 indicate that low orders of perturbation theory are not reliable for accurate results. Although not required mathematically, S(sub 2) is always less than T(sub 1) for the examples studied here.
-
Dunbar, R; Naidoo, P; Beyers, N; Langley, I
2017-04-01
Cape Town, South Africa. To compare the diagnostic yield for smear/culture and Xpert® MTB/RIF algorithms and to investigate the mechanisms influencing tuberculosis (TB) yield. We developed and validated an operational model of the TB diagnostic process, first with the smear/culture algorithm and then with the Xpert algorithm. We modelled scenarios by varying TB prevalence, adherence to diagnostic algorithms and human immunodeficiency virus (HIV) status. This enabled direct comparisons of diagnostic yield in the two algorithms to be made. Routine data showed that diagnostic yield had decreased over the period of the Xpert algorithm roll-out compared to the yield when the smear/culture algorithm was in place. However, modelling yield under identical conditions indicated a 13.3% increase in diagnostic yield from the Xpert algorithm compared to smear/culture. The model demonstrated that the extensive use of culture in the smear/culture algorithm and the decline in TB prevalence are the main factors contributing to not finding an increase in diagnostic yield in the routine data. We demonstrate the benefits of an operational model to determine the effect of scale-up of a new diagnostic algorithm, and recommend that policy makers use operational modelling to make appropriate decisions before new diagnostic algorithms are scaled up.
-
Antibody detection tests improve the sensitivity of tuberculosis diagnosis in cattle.
Casal, C; Infantes, J A; Risalde, M A; Díez-Guerrier, A; Domínguez, M; Moreno, I; Romero, B; de Juan, L; Sáez, J L; Juste, R; Gortázar, C; Domínguez, L; Bezos, J
2017-06-01
We evaluated the sensitivity (Se) of the single cervical intradermal tuberculin (SIT) test, two interferon-gamma (IFN-γ) assays and three different antibody detection techniques for bovine tuberculosis (bTB) diagnosis in 131 mixed beef breed cattle. The results of the diagnostic techniques performed over the whole herd, and over the animals confirmed as infected based on the presence of lesions compatible with the disease and/or M. bovis isolation were compared to determine apparent prevalence (AP) and Se. The Se of the SIT test (severe interpretation) was 63.7% (95% CI, 54.54-72.00), while the Se of the IFN-γ assays ranged between 60.2% and 92%. The proportion of infected cattle detected by the different antibody detection techniques ranged from 65.5% to 87.6%. Three of the antibody detection techniques yielded a significant higher (p<0.05) Se than that achieved with the official diagnostic techniques. In addition, the interpretation in parallel of cellular and antibody detection techniques reached the highest Se: 98.2% (95% CI, 93.78-99.51) suggesting that the use of diagnostic techniques detecting both cellular and humoral responses could be considered as an alternative in the control of bTB outbreaks in high prevalence settings. Copyright © 2017 Elsevier Ltd. All rights reserved.
-
Sansović, Ivona; Ivankov, Ana-Maria; Bobinec, Adriana; Kero, Mijana; Barišić, Ingeborg
2017-06-14
To determine the diagnostic yield and criteria that could help to classify and interpret the copy number variations (CNVs) detected by chromosomal microarray (CMA) technique in patients with congenital and developmental abnormalities including dysmorphia, developmental delay (DD) or intellectual disability (ID), autism spectrum disorders (ASD) and congenital anomalies (CA). CMA analysis was performed in 337 patients with DD/ID with or without dysmorphism, ASD, and/or CA. In 30 of 337 patients, chromosomal imbalances had previously been detected by classical cytogenetic and molecular cytogenetic methods. In 73 of 337 patients, clinically relevant variants were detected and better characterized. Most of them were >1 Mb. Variants of unknown clinical significance (VOUS) were discovered in 35 patients. The most common VOUS size category was <300 kb (40.5%). Deletions and de novo imbalances were more frequent in pathogenic CNV than in VOUS category. CMA had a high diagnostic yield of 43/307, excluding patients previously detected by other methods. CMA was valuable in establishing the diagnosis in a high proportion of patients. Criteria for classification and interpretation of CNVs include CNV size and type, mode of inheritance, and genotype-phenotype correlation. Agilent ISCA v2 Human Genome 8x60 K oligonucleotide microarray format proved to be reasonable resolution for clinical use, particularly in the regions that are recommended by the International Standard Cytogenomic Array (ISCA) Consortium and associated with well-established syndromes.
-
Diagnostic reliability of MMPI-2 computer-based test interpretations.
Pant, Hina; McCabe, Brian J; Deskovitz, Mark A; Weed, Nathan C; Williams, John E
2014-09-01
Reflecting the common use of the MMPI-2 to provide diagnostic considerations, computer-based test interpretations (CBTIs) also typically offer diagnostic suggestions. However, these diagnostic suggestions can sometimes be shown to vary widely across different CBTI programs even for identical MMPI-2 profiles. The present study evaluated the diagnostic reliability of 6 commercially available CBTIs using a 20-item Q-sort task developed for this study. Four raters each sorted diagnostic classifications based on these 6 CBTI reports for 20 MMPI-2 profiles. Two questions were addressed. First, do users of CBTIs understand the diagnostic information contained within the reports similarly? Overall, diagnostic sorts of the CBTIs showed moderate inter-interpreter diagnostic reliability (mean r = .56), with sorts for the 1/2/3 profile showing the highest inter-interpreter diagnostic reliability (mean r = .67). Second, do different CBTIs programs vary with respect to diagnostic suggestions? It was found that diagnostic sorts of the CBTIs had a mean inter-CBTI diagnostic reliability of r = .56, indicating moderate but not strong agreement across CBTIs in terms of diagnostic suggestions. The strongest inter-CBTI diagnostic agreement was found for sorts of the 1/2/3 profile CBTIs (mean r = .71). Limitations and future directions are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.
-
Boyce, Matthew R; Menya, Diana; Turner, Elizabeth L; Laktabai, Jeremiah; Prudhomme-O'Meara, Wendy
2018-05-18
Malaria rapid diagnostic tests (RDTs) are a simple, point-of-care technology that can improve the diagnosis and subsequent treatment of malaria. They are an increasingly common diagnostic tool, but concerns remain about their use by community health workers (CHWs). These concerns regard the long-term trends relating to infection prevention measures, the interpretation of test results and adherence to treatment protocols. This study assessed whether CHWs maintained their competency at conducting RDTs over a 12-month timeframe, and if this competency varied with specific CHW characteristics. From June to September, 2015, CHWs (n = 271) were trained to conduct RDTs using a 3-day validated curriculum and a baseline assessment was completed. Between June and August, 2016, CHWs (n = 105) were randomly selected and recruited for follow-up assessments using a 20-step checklist that classified steps as relating to safety, accuracy, and treatment; 103 CHWs participated in follow-up assessments. Poisson regressions were used to test for associations between error count data at follow-up and Poisson regression models fit using generalized estimating equations were used to compare data across time-points. At both baseline and follow-up observations, at least 80% of CHWs correctly completed 17 of the 20 steps. CHWs being 50 years of age or older was associated with increased total errors and safety errors at baseline and follow-up. At follow-up, prior experience conducting RDTs was associated with fewer errors. Performance, as it related to the correct completion of all checklist steps and safety steps, did not decline over the 12 months and performance of accuracy steps improved (mean error ratio: 0.51; 95% CI 0.40-0.63). Visual interpretation of RDT results yielded a CHW sensitivity of 92.0% and a specificity of 97.3% when compared to interpretation by the research team. None of the characteristics investigated was found to be significantly associated with RDT interpretation. With training, most CHWs performing RDTs maintain diagnostic testing competency over at least 12 months. CHWs generally perform RDTs safely and accurately interpret results. Younger age and prior experiences with RDTs were associated with better testing performance. Future research should investigate the mode by which CHW characteristics impact RDT procedures.
-
Radiologists’ Interpretive Skills in Screening vs. Diagnostic Mammography: Are They Related?
Elmore, Joann G.; Cook, Andrea J.; Bogart, Andy; Carney, Patricia A.; Geller, Berta; Taplin, Stephen; Buist, Diana SM; Onega, Tracy; Lee, Christoph I.; Miglioretti, Diana L.
2016-01-01
Purpose To determine whether radiologists who perform well in screening also perform well in interpreting diagnostic mammography. Materials & Methods We evaluated the accuracy of 468 radiologists interpreting 2,234,947 screening and 196,164 diagnostic mammograms. Adjusting for site, radiologist, and patient characteristics, we identified radiologists with performance in the highest tertile and compared to those with lower performance. Results A moderate correlation was noted for radiologists’ accuracy when interpreting screening versus their accuracy on diagnostic exams: sensitivity (rspearman=0.51, 95% CI: 0.22, 0.80; P=0.0006), specificity (rspearman=0.40, 95% CI: 0.30, 0.49; P<0.0001). Conclusion Different educational approaches to screening and diagnostic imaging should be considered. PMID:27438069
-
Delineating Extramammary Findings at Breast MR Imaging.
Gao, Yiming; Ibidapo, Opeyemi; Toth, Hildegard K; Moy, Linda
2017-01-01
Breast magnetic resonance (MR) imaging is the only breast imaging modality that consistently encompasses extramammary structures in the thorax and upper abdomen. Incidental extramammary findings on breast MR images of patients with a history of breast cancer or other malignancies are significantly more likely to be malignant and may affect staging and treatment. An understanding of the frequency, distribution, and context of extramammary findings on breast MR images and a familiarity with common and uncommon sites of breast cancer metastasis inform the differential diagnosis and prompt the appropriate diagnostic next step, to differentiate benign from malignant findings. High-yield organ systems on breast MR images, as reflected by a high positive predictive value for malignancy, are correlated with known distant sites of breast cancer metastasis in the bone, lung, liver, and lymph nodes. Staging is considered when disease involves the skin and chest wall. Unusual sites of breast cancer metastasis from invasive lobular carcinoma are discussed, including the gastrointestinal tract, peritoneum, and adrenal glands. Nonmalignant clinically important findings involving the cardiovascular and gastrointestinal systems are reviewed, and potential pitfalls in diagnosis and interpretation are highlighted. A consistently systematic diagnostic approach is emphasized for identifying extramammary abnormalities on breast MR images. All things considered, the radiologist should be able to improve diagnostic sensitivity and specificity while interpreting extramammary findings on breast MR images. © RSNA, 2017.
-
Segura-Grau, A; Sáez-Fernández, A; Rodríguez-Lorenzo, A; Díaz-Rodríguez, N
2014-01-01
Ultrasound is a non-invasive, accessible, and versatile diagnostic technique that uses high frequency ultrasound waves to define outline the organs of the human body, with no ionising radiation, in real time and with the capacity to visual several planes. The high diagnostic yield of the technique, together with its ease of uses plus the previously mentioned characteristics, has currently made it a routine method in daily medical practice. It is for this reason that the multidisciplinary character of this technique is being strengthened every day. To be able to perform the technique correctly requires knowledge of the physical basis of ultrasound, the method and the equipment, as well as of the human anatomy, in order to have the maximum information possible to avoid diagnostic errors due to poor interpretation or lack of information. Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.
-
Cardiac Auscultation Using Smartphones: Pilot Study.
Kang, Si-Hyuck; Joe, Byunggill; Yoon, Yeonyee; Cho, Goo-Yeong; Shin, Insik; Suh, Jung-Won
2018-02-28
Cardiac auscultation is a cost-effective, noninvasive screening tool that can provide information about cardiovascular hemodynamics and disease. However, with advances in imaging and laboratory tests, the importance of cardiac auscultation is less appreciated in clinical practice. The widespread use of smartphones provides opportunities for nonmedical expert users to perform self-examination before hospital visits. The objective of our study was to assess the feasibility of cardiac auscultation using smartphones with no add-on devices for use at the prehospital stage. We performed a pilot study of patients with normal and pathologic heart sounds. Heart sounds were recorded on the skin of the chest wall using 3 smartphones: the Samsung Galaxy S5 and Galaxy S6, and the LG G3. Recorded heart sounds were processed and classified by a diagnostic algorithm using convolutional neural networks. We assessed diagnostic accuracy, as well as sensitivity, specificity, and predictive values. A total of 46 participants underwent heart sound recording. After audio file processing, 30 of 46 (65%) heart sounds were proven interpretable. Atrial fibrillation and diastolic murmur were significantly associated with failure to acquire interpretable heart sounds. The diagnostic algorithm classified the heart sounds into the correct category with high accuracy: Galaxy S5, 90% (95% CI 73%-98%); Galaxy S6, 87% (95% CI 69%-96%); and LG G3, 90% (95% CI 73%-98%). Sensitivity, specificity, positive predictive value, and negative predictive value were also acceptable for the 3 devices. Cardiac auscultation using smartphones was feasible. Discrimination using convolutional neural networks yielded high diagnostic accuracy. However, using the built-in microphones alone, the acquisition of reproducible and interpretable heart sounds was still a major challenge. ClinicalTrials.gov NCT03273803; https://clinicaltrials.gov/ct2/show/NCT03273803 (Archived by WebCite at http://www.webcitation.org/6x6g1fHIu). ©Si-Hyuck Kang, Byunggill Joe, Yeonyee Yoon, Goo-Yeong Cho, Insik Shin, Jung-Won Suh. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 28.02.2018.
-
Cardiac Auscultation Using Smartphones: Pilot Study
Kang, Si-Hyuck; Joe, Byunggill; Yoon, Yeonyee; Cho, Goo-Yeong; Shin, Insik
2018-01-01
Background Cardiac auscultation is a cost-effective, noninvasive screening tool that can provide information about cardiovascular hemodynamics and disease. However, with advances in imaging and laboratory tests, the importance of cardiac auscultation is less appreciated in clinical practice. The widespread use of smartphones provides opportunities for nonmedical expert users to perform self-examination before hospital visits. Objective The objective of our study was to assess the feasibility of cardiac auscultation using smartphones with no add-on devices for use at the prehospital stage. Methods We performed a pilot study of patients with normal and pathologic heart sounds. Heart sounds were recorded on the skin of the chest wall using 3 smartphones: the Samsung Galaxy S5 and Galaxy S6, and the LG G3. Recorded heart sounds were processed and classified by a diagnostic algorithm using convolutional neural networks. We assessed diagnostic accuracy, as well as sensitivity, specificity, and predictive values. Results A total of 46 participants underwent heart sound recording. After audio file processing, 30 of 46 (65%) heart sounds were proven interpretable. Atrial fibrillation and diastolic murmur were significantly associated with failure to acquire interpretable heart sounds. The diagnostic algorithm classified the heart sounds into the correct category with high accuracy: Galaxy S5, 90% (95% CI 73%-98%); Galaxy S6, 87% (95% CI 69%-96%); and LG G3, 90% (95% CI 73%-98%). Sensitivity, specificity, positive predictive value, and negative predictive value were also acceptable for the 3 devices. Conclusions Cardiac auscultation using smartphones was feasible. Discrimination using convolutional neural networks yielded high diagnostic accuracy. However, using the built-in microphones alone, the acquisition of reproducible and interpretable heart sounds was still a major challenge. Trial Registration ClinicalTrials.gov NCT03273803; https://clinicaltrials.gov/ct2/show/NCT03273803 (Archived by WebCite at http://www.webcitation.org/6x6g1fHIu) PMID:29490899
-
ERIC Educational Resources Information Center
Pierangelo, Roger; Giuliani, George
This manual is a guide to the special education diagnostic process and covers the various stages of evaluation, interpretation, diagnosis, prescription, and remediation. Test information includes: explanations of the most commonly used diagnostic tests, coverage of the areas measured by each test, interpretation of test patterns for commonly used…
-
Theurer, M E; White, B J; Larson, R L; Schroeder, T C
2015-03-01
Bovine respiratory disease is an economically important syndrome in the beef industry, and diagnostic accuracy is important for optimal disease management. The objective of this study was to determine whether improving diagnostic sensitivity or specificity was of greater economic value at varied levels of respiratory disease prevalence by using Monte Carlo simulation. Existing literature was used to populate model distributions of published sensitivity, specificity, and performance (ADG, carcass weight, yield grade, quality grade, and mortality risk) differences among calves based on clinical respiratory disease status. Data from multiple cattle feeding operations were used to generate true ranges of respiratory disease prevalence and associated mortality. Input variables were combined into a single model that calculated estimated net returns for animals by diagnostic category (true positive, false positive, false negative, and true negative) based on the prevalence, sensitivity, and specificity for each iteration. Net returns for each diagnostic category were multiplied by the proportion of animals in each diagnostic category to determine group profitability. Apparent prevalence was categorized into low (<15%) and high (≥15%) groups. For both apparent prevalence categories, increasing specificity created more rapid, positive change in net returns than increasing sensitivity. Improvement of diagnostic specificity, perhaps through a confirmatory test interpreted in series or pen-level diagnostics, can increase diagnostic value more than improving sensitivity. Mortality risk was the primary driver for net returns. The results from this study are important for determining future research priorities to analyze diagnostic techniques for bovine respiratory disease and provide a novel way for modeling diagnostic tests.
-
Kalinga, Akili K; Mwanziva, Charles; Chiduo, Sarah; Mswanya, Christopher; Ishengoma, Deus I; Francis, Filbert; Temu, Lucky; Mahikwano, Lucas; Mgata, Saidi; Amoo, George; Anova, Lalaine; Wurrapa, Eyako; Zwingerman, Nora; Ferro, Santiago; Bhat, Geeta; Fine, Ian; Vesely, Brian; Waters, Norman; Kreishman-Deitrick, Mara; Hickman, Mark; Paris, Robert; Kamau, Edwin; Ohrt, Colin; Kavishe, Reginald A
2018-05-29
Although microscopy is a standard diagnostic tool for malaria and the gold standard, it is infrequently used because of unavailability of laboratory facilities and the absence of skilled readers in poor resource settings. Malaria rapid diagnostic tests (RDT) are currently used instead of or as an adjunct to microscopy. However, at very low parasitaemia (usually < 100 asexual parasites/µl), the test line on malaria rapid diagnostic tests can be faint and consequently hard to visualize and this may potentially affect the interpretation of the test results. Fio Corporation (Canada), developed an automated RDT reader named Deki Reader™ for automatic analysis and interpretation of rapid diagnostic tests. This study aimed to compare visual assessment and automated Deki Reader evaluations to interpret malaria rapid diagnostic tests against microscopy. Unlike in the previous studies where expert laboratory technicians interpreted the test results visually and operated the device, in this study low cadre health care workers who have not attended any formal professional training in laboratory sciences were employed. Finger prick blood from 1293 outpatients with fever was tested for malaria using RDT and Giemsa-stained microscopy for thick and thin blood smears. Blood samples for RDTs were processed according to manufacturers' instructions automated in the Deki Reader. Results of malaria diagnoses were compared between visual and the automated devise reading of RDT and microscopy. The sensitivity of malaria rapid diagnostic test results interpreted by the Deki Reader was 94.1% and that of visual interpretation was 93.9%. The specificity of malaria rapid diagnostic test results was 71.8% and that of human interpretation was 72.0%. The positive predictive value of malaria RDT results by the Deki Reader and visual interpretation was 75.8 and 75.4%, respectively, while the negative predictive values were 92.8 and 92.4%, respectively. The accuracy of RDT as interpreted by DR and visually was 82.6 and 82.1%, respectively. There was no significant difference in performance of RDTs interpreted by either automated DR or visually by unskilled health workers. However, despite the similarities in performance parameters, the device has proven useful because it provides stepwise guidance on processing RDT, data transfer and reporting.
-
The inverse skin effect in the Z-pinch and plasma focus
DOE Office of Scientific and Technical Information (OSTI.GOV)
Usenko, P. L., E-mail: otd4@expd.vniief.ru; Gaganov, V. V.
The inverse skin effect and its influence on the dynamics of high-current Z-pinch and plasma focus discharges in deuterium are analyzed. It is shown that the second compression responsible for the major fraction of the neutron yield can be interpreted as a result of the inverse skin effect resulting in the axial concentration of the longitudinal current density and the appearance of a reversed current in the outer layers of plasma pinches. Possible conditions leading to the enhancement of the inverse skin effect and accessible for experimental verification by modern diagnostics are formulated.
-
Décary, Simon; Frémont, Pierre; Pelletier, Bruno; Fallaha, Michel; Belzile, Sylvain; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Feldman, Debbie; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François
2018-04-01
To assess the validity of diagnostic clusters combining history elements and physical examination tests to diagnose or exclude patellofemoral pain (PFP). Prospective diagnostic study. Orthopedic outpatient clinics, family medicine clinics, and community-dwelling. Consecutive patients (N=279) consulting one of the participating orthopedic surgeons (n=3) or sport medicine physicians (n=2) for any knee complaint. Not applicable. History elements and physical examination tests were obtained by a trained physiotherapist blinded to the reference standard: a composite diagnosis including both physical examination tests and imaging results interpretation performed by an expert physician. Penalized logistic regression (least absolute shrinkage and selection operator) was used to identify history elements and physical examination tests associated with the diagnosis of PFP, and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures including sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios with associated 95% confidence intervals (CIs) were calculated. Two hundred seventy-nine participants were evaluated, and 75 had a diagnosis of PFP (26.9%). Different combinations of history elements and physical examination tests including the age of participants, knee pain location, difficulty descending stairs, patellar facet palpation, and passive knee extension range of motion were associated with a diagnosis of PFP and used in clusters to accurately discriminate between individuals with PFP and individuals without PFP. Two diagnostic clusters developed to confirm the presence of PFP yielded a positive likelihood ratio of 8.7 (95% CI, 5.2-14.6) and 3 clusters to exclude PFP yielded a negative likelihood ratio of .12 (95% CI, .06-.27). Diagnostic clusters combining common history elements and physical examination tests that can accurately diagnose or exclude PFP compared to various knee disorders were developed. External validation is required before clinical use. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
-
Irwin, R John; Irwin, Timothy C
2011-06-01
Making clinical decisions on the basis of diagnostic tests is an essential feature of medical practice and the choice of the decision threshold is therefore crucial. A test's optimal diagnostic threshold is the threshold that maximizes expected utility. It is given by the product of the prior odds of a disease and a measure of the importance of the diagnostic test's sensitivity relative to its specificity. Choosing this threshold is the same as choosing the point on the Receiver Operating Characteristic (ROC) curve whose slope equals this product. We contend that a test's likelihood ratio is the canonical decision variable and contrast diagnostic thresholds based on likelihood ratio with two popular rules of thumb for choosing a threshold. The two rules are appealing because they have clear graphical interpretations, but they yield optimal thresholds only in special cases. The optimal rule can be given similar appeal by presenting indifference curves, each of which shows a set of equally good combinations of sensitivity and specificity. The indifference curve is tangent to the ROC curve at the optimal threshold. Whereas ROC curves show what is feasible, indifference curves show what is desirable. Together they show what should be chosen. Copyright © 2010 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.
-
Endobronchial Ultrasound-guided Transbronchial Needle Aspiration Using 19-G Needle for Sarcoidosis.
Balwan, Akshu
2018-05-16
Flexible bronchoscopy with endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) is increasingly being used to obtain pathology specimens for diagnosis of sarcoidosis. There is wide variation in reported diagnostic yield in literature. New TBNA needles are available in the market but data are lacking about their diagnostic yield especially for sarcoidosis. This study reports the diagnostic yield of bronchoscopy with EBUS-TBNA using ViziShot FLEX 19-G needle in a series of patients with suspected sarcoidosis. This is a retrospective chart review for diagnostic yield of the 19-G EBUS-TBNA needle for suspected sarcoidosis. Eighty-six EBUS bronchoscopies were performed, 15 were done with clinical suspicion of sarcoidosis. The 19-G needle was used for all cases of suspected sarcoidosis. The procedure was diagnostic of sarcoidosis in 14 (93.3%) patients by TBNA with 1 nondiagnostic bronchoscopy. Procedural diagnostic yield was 93.3%. Eighty-five percent (28/33) of sampled lymph nodes were positive for noncaseating granulomas. The yield of transbronchial lung biopsy (TBLB) and endobronchial lung biopsy was 38% (5/13) and 43% (6/14), respectively. TBLB and endobronchial lung biopsy did not add to the diagnostic yield of the procedure. No significant adverse events were noted. This series reports a higher diagnostic yield than most other published studies and opens platform for direct comparison of each available needle. It also adds to the safety data for this larger needle. In addition, it raises doubt into utility of TBLB for diagnosis of sarcoidosis, which can increase the procedural complications.
-
NASA Astrophysics Data System (ADS)
Einstein, Gnanatheepam; Udayakumar, Kanniyappan; Aruna, Prakasarao; Ganesan, Singaravelu
2017-03-01
Fluorescence of Protein has been widely used in diagnostic oncology for characterizing cellular metabolism. However, the intensity of fluorescence emission is affected due to the absorbers and scatterers in tissue, which may lead to error in estimating exact protein content in tissue. Extraction of intrinsic fluorescence from measured fluorescence has been achieved by different methods. Among them, Monte Carlo based method yields the highest accuracy for extracting intrinsic fluorescence. In this work, we have attempted to generate a lookup table for Monte Carlo simulation of fluorescence emission by protein. Furthermore, we fitted the generated lookup table using an empirical relation. The empirical relation between measured and intrinsic fluorescence is validated using tissue phantom experiments. The proposed relation can be used for estimating intrinsic fluorescence of protein for real-time diagnostic applications and thereby improving the clinical interpretation of fluorescence spectroscopic data.
-
Ginter, Paula S; Varma, Sonal; Liu, Yi-Fang; Shin, Sandra J
2015-12-01
The Minimal Carcinoma (MC) Triple Stain is a tri-chromogen multiplex immunostain (CK7, p63, and E-cadherin) helpful in classifying morphologically ambiguous and/or small carcinomas as either ductal or lobular and/or in situ or invasive. We compared the utility of this stain with two commercially available duplex/multiplex immunostains: Breast Triple Stain (BTS) (Clarient, Aliso Viejo, CA; CK5, p63, and CK8/18) and LC/DC Breast Cocktail (LCDC) (Biocare, Concord, CA; E-cadherin and p120). Ninety-seven mammary carcinomas stained with the MC Triple Stain, BTS, and LCDC were compared. The MC Triple Stain, LCDC, and BTS were diagnostic in 90 (93%) of 97, 82 (85%) of 97, and 85 (88%) of 97 of cases, respectively. All stains showed decreased diagnostic utility due to variability in tissue integrity, quality of the staining, and/or ease of interpretation. In cases where all immunostains were interpretable, the MC Triple Stain yielded the most information. When technically sufficient, all three immunostains demonstrated relative strengths and weaknesses in their ability to provide diagnostic information with the highest consistency and ease of use. Many cases stained with LCDC were technically insufficient due to a suboptimal staining protocol provided by the company. Overall, the MC Triple Stain outperformed BTS and LCDC by more consistently providing more diagnostic information. The MC Triple Stain is a viable alternative to other multiplex immunostains in evaluating small foci of carcinoma, particularly when both the histologic type and extent of disease (in situ vs invasive) require clarification. Copyright© by the American Society for Clinical Pathology.
-
2010-01-01
Background Proton Magnetic Resonance (MR) Spectroscopy (MRS) is a widely available technique for those clinical centres equipped with MR scanners. Unlike the rest of MR-based techniques, MRS yields not images but spectra of metabolites in the tissues. In pathological situations, the MRS profile changes and this has been particularly described for brain tumours. However, radiologists are frequently not familiar to the interpretation of MRS data and for this reason, the usefulness of decision-support systems (DSS) in MRS data analysis has been explored. Results This work presents the INTERPRET DSS version 3.0, analysing the improvements made from its first release in 2002. Version 3.0 is aimed to be a program that 1st, can be easily used with any new case from any MR scanner manufacturer and 2nd, improves the initial analysis capabilities of the first version. The main improvements are an embedded database, user accounts, more diagnostic discrimination capabilities and the possibility to analyse data acquired under additional data acquisition conditions. Other improvements include a customisable graphical user interface (GUI). Most diagnostic problems included have been addressed through a pattern-recognition based approach, in which classifiers based on linear discriminant analysis (LDA) were trained and tested. Conclusions The INTERPRET DSS 3.0 allows radiologists, medical physicists, biochemists or, generally speaking, any person with a minimum knowledge of what an MR spectrum is, to enter their own SV raw data, acquired at 1.5 T, and to analyse them. The system is expected to help in the categorisation of MR Spectra from abnormal brain masses. PMID:21114820
-
Maltha, Jessica; Gillet, Philippe; Heutmekers, Marloes; Bottieau, Emmanuel; Van Gompel, Alfons; Jacobs, Jan
2013-01-01
In the past malaria rapid diagnostic tests (RDTs) for self-diagnosis by travelers were considered suboptimal due to poor performance. Nowadays RDTs for self-diagnosis are marketed and available through the internet. The present study assessed RDT products marketed for self-diagnosis for diagnostic accuracy and quality of labeling, content and instructions for use (IFU). Diagnostic accuracy of eight RDT products was assessed with a panel of stored whole blood samples comprising the four Plasmodium species (n = 90) as well as Plasmodium negative samples (n = 10). IFUs were assessed for quality of description of procedure and interpretation and for lay-out and readability level. Errors in packaging and content were recorded. Two products gave false-positive test lines in 70% and 80% of Plasmodium negative samples, precluding their use. Of the remaining products, 4/6 had good to excellent sensitivity for the diagnosis of Plasmodium falciparum (98.2%-100.0%) and Plasmodium vivax (93.3%-100.0%). Sensitivity for Plasmodium ovale and Plasmodium malariae diagnosis was poor (6.7%-80.0%). All but one product yielded false-positive test lines after reading beyond the recommended reading time. Problems with labeling (not specifying target antigens (n = 3), and content (desiccant with no humidity indicator (n = 6)) were observed. IFUs had major shortcomings in description of test procedure and interpretation, poor readability and lay-out and user-unfriendly typography. Strategic issues (e.g. the need for repeat testing and reasons for false-negative tests) were not addressed in any of the IFUs. Diagnostic accuracy of RDTs for self-diagnosis was variable, with only 4/8 RDT products being reliable for the diagnosis of P. falciparum and P. vivax, and none for P. ovale and P. malariae. RDTs for self-diagnosis need improvements in IFUs (content and user-friendliness), labeling and content before they can be considered for self-diagnosis by the traveler.
-
Maltha, Jessica; Gillet, Philippe; Heutmekers, Marloes; Bottieau, Emmanuel; Van Gompel, Alfons; Jacobs, Jan
2013-01-01
Introduction In the past malaria rapid diagnostic tests (RDTs) for self-diagnosis by travelers were considered suboptimal due to poor performance. Nowadays RDTs for self-diagnosis are marketed and available through the internet. The present study assessed RDT products marketed for self-diagnosis for diagnostic accuracy and quality of labeling, content and instructions for use (IFU). Methods Diagnostic accuracy of eight RDT products was assessed with a panel of stored whole blood samples comprising the four Plasmodium species (n = 90) as well as Plasmodium negative samples (n = 10). IFUs were assessed for quality of description of procedure and interpretation and for lay-out and readability level. Errors in packaging and content were recorded. Results Two products gave false-positive test lines in 70% and 80% of Plasmodium negative samples, precluding their use. Of the remaining products, 4/6 had good to excellent sensitivity for the diagnosis of Plasmodium falciparum (98.2%–100.0%) and Plasmodium vivax (93.3%–100.0%). Sensitivity for Plasmodium ovale and Plasmodium malariae diagnosis was poor (6.7%–80.0%). All but one product yielded false-positive test lines after reading beyond the recommended reading time. Problems with labeling (not specifying target antigens (n = 3), and content (desiccant with no humidity indicator (n = 6)) were observed. IFUs had major shortcomings in description of test procedure and interpretation, poor readability and lay-out and user-unfriendly typography. Strategic issues (e.g. the need for repeat testing and reasons for false-negative tests) were not addressed in any of the IFUs. Conclusion Diagnostic accuracy of RDTs for self-diagnosis was variable, with only 4/8 RDT products being reliable for the diagnosis of P. falciparum and P. vivax, and none for P. ovale and P. malariae. RDTs for self-diagnosis need improvements in IFUs (content and user-friendliness), labeling and content before they can be considered for self-diagnosis by the traveler. PMID:23301027
-
Bowling, Mark R; Kohan, Matthew W; Walker, Paul; Efird, Jimmy; Ben Or, Sharon
2015-01-01
Navigational bronchoscopy is utilized to guide biopsies of peripheral lung nodules and place fiducial markers for treatment of limited stage lung cancer with stereotactic body radiotherapy. The type of sedation used for this procedure remains controversial. We performed a retrospective chart review to evaluate the differences of diagnostic yield and overall success of the procedure based on anesthesia type. Electromagnetic navigational bronchoscopy was performed using the superDimension software system. Once the targeted lesion was within reach, multiple tissue samples were obtained. Statistical analysis was used to correlate the yield with the type of sedation among other factors. A successful procedure was defined if a diagnosis was made or a fiducial marker was adequately placed. Navigational bronchoscopy was performed on a total of 120 targeted lesions. The overall complication rate of the procedure was 4.1%. The diagnostic yield and success of the procedure was 74% and 87%, respectively. Duration of the procedure was the only significant difference between the general anesthesia and IV sedation groups (mean, 58 vs. 43 min, P=0.0005). A larger tumor size was associated with a higher diagnostic yield (P=0.032). All other variables in terms of effect on diagnostic yield and an unsuccessful procedure did not meet statistical significance. Navigational bronchoscopy is a safe and effective pulmonary diagnostic tool with relatively low complication rate. The diagnostic yield and overall success of the procedure does not seem to be affected by the type of sedation used.
-
Ali, Muhammad S; Sethi, Jaskaran; Taneja, Amit; Musani, Ali; Maldonado, Fabien
2018-06-07
Indeterminate peripheral pulmonary lesions often require tissue diagnosis. If non-surgical biopsy techniques are considered, deciding between bronchoscopic transbronchial vs. CT guided transthoracic biopsy can be difficult. The former has a low diagnostic yield with a low complication risk, while the latter has a better diagnostic yield but a higher complication rate. Investigators have looked at various lesion characteristics that can predict the diagnostic yield of guided bronchoscopic biopsies. While consensus exists that larger size and proximity to the hilum increase the diagnostic yield, there is ongoing debate about the association between CT bronchus sign (air-filled bronchus in close proximity of the lesion as seen on CT) and the diagnostic yield of guided bronchoscopic modalities. To perform a meta-analysis and systematic review, determining the association between CT bronchus sign and the diagnostic yield of guided bronchoscopy for peripheral pulmonary lesions. MEDLINE, Embase, Scopus and Google Scholar were searched in January 2018 for guided bronchoscopy studies that had assessed the impact of CT bronchus sign on the diagnostic yield. The quality of included studies was assessed using Quality Assessment, Data Abstraction and Synthesis-2 tool. Meta-analysis was performed using MedCalc (version 18). Odds ratios were used to compare yield of lesions with and without bronchus sign. Random effects model was used when significant heterogeneity was observed (I2>40%). For 2199 lesions with CT bronchus sign, the overall weighted diagnostic yield was 74.1% (95% CI: 68.3-79.5%). For 971 lesions without CT bronchus sign, the overall weighted diagnostic yield was 49.6% (95% CI: 39.6-59.5%). The odds ratio for successfully diagnosing a lesion with CT bronchus was 3.4 (95% CI: 2.4-5.0). Possible sources of heterogeneity in the meta-analysis included differences in study designs, guidance modalities and cancer prevalence. The odds ratio for successfully diagnosing a lesion with CT bronchus sign was relatively lower for prospective studies. Peripheral pulmonary lesions with CT bronchus sign are more likely to be diagnosed with guided bronchoscopy as compared to the lesions without CT bronchus sign. Clinicians should consider this along with the lesion size and distance from hilum, when contemplating guided bronchoscopy for peripheral pulmonary lesions. To perform a meta-analysis and systematic review, determining the impact of CT bronchus sign on the diagnostic yield of guided bronchoscopy for peripheral pulmonary lesions. MEDLINE, Embase, Scopus and Google Scholar were searched in January 2018 for guided bronchoscopy studies that had assessed the impact of CT bronchus sign on the diagnostic yield. The quality of included studies was assessed using Quality Assessment, Data Abstraction and Synthesis-2 tool. Meta-analysis was performed using MedCalc (version 18). Odds ratios were used to compare yield of lesions with and without bronchus sign. Random effects model was used when significant heterogeneity was observed (I2>40%). For 2199 lesions with CT bronchus sign, the overall weighted diagnostic yield was 74.1% (95% CI: 68.3-79.5%). For 971 lesions without CT bronchus, the overall weighted diagnostic yield was 49.6% (95% CI: 39.6-59.5%). The odds ratio for successfully diagnosing a lesion with CT bronchus was 3.4 (95% CI: 2.4-5.0). I² index was 62.1 therefore random effects model was used. Peripheral pulmonary lesions with CT bronchus sign are much more likely to be successfully diagnosed with guided bronchoscopy as compared to the lesions without CT bronchus sign. Clinicians should consider the presence (or absence) of CT bronchus sign along with the size of the lesion and distance from the hilum, when contemplating guided bronchoscopic modalities for peripheral pulmonary lesions.
-
Mordini, Federico E; Haddad, Tariq; Hsu, Li-Yueh; Kellman, Peter; Lowrey, Tracy B; Aletras, Anthony H; Bandettini, W Patricia; Arai, Andrew E
2014-01-01
This study's primary objective was to determine the sensitivity, specificity, and accuracy of fully quantitative stress perfusion cardiac magnetic resonance (CMR) versus a reference standard of quantitative coronary angiography. We hypothesized that fully quantitative analysis of stress perfusion CMR would have high diagnostic accuracy for identifying significant coronary artery stenosis and exceed the accuracy of semiquantitative measures of perfusion and qualitative interpretation. Relatively few studies apply fully quantitative CMR perfusion measures to patients with coronary disease and comparisons to semiquantitative and qualitative methods are limited. Dual bolus dipyridamole stress perfusion CMR exams were performed in 67 patients with clinical indications for assessment of myocardial ischemia. Stress perfusion images alone were analyzed with a fully quantitative perfusion (QP) method and 3 semiquantitative methods including contrast enhancement ratio, upslope index, and upslope integral. Comprehensive exams (cine imaging, stress/rest perfusion, late gadolinium enhancement) were analyzed qualitatively with 2 methods including the Duke algorithm and standard clinical interpretation. A 70% or greater stenosis by quantitative coronary angiography was considered abnormal. The optimum diagnostic threshold for QP determined by receiver-operating characteristic curve occurred when endocardial flow decreased to <50% of mean epicardial flow, which yielded a sensitivity of 87% and specificity of 93%. The area under the curve for QP was 92%, which was superior to semiquantitative methods: contrast enhancement ratio: 78%; upslope index: 82%; and upslope integral: 75% (p = 0.011, p = 0.019, p = 0.004 vs. QP, respectively). Area under the curve for QP was also superior to qualitative methods: Duke algorithm: 70%; and clinical interpretation: 78% (p < 0.001 and p < 0.001 vs. QP, respectively). Fully quantitative stress perfusion CMR has high diagnostic accuracy for detecting obstructive coronary artery disease. QP outperforms semiquantitative measures of perfusion and qualitative methods that incorporate a combination of cine, perfusion, and late gadolinium enhancement imaging. These findings suggest a potential clinical role for quantitative stress perfusion CMR. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
-
Boonsarngsuk, Viboon; Kanoksil, Wasana; Laungdamerongchai, Sarangrat
2015-04-01
There are many sampling techniques dedicated to radial endobronchial ultrasound (R-EBUS) guided flexible bronchoscopy (FB). However, data regarding the diagnostic performances among bronchoscopic sampling techniques is limited. This study was conducted to compare the diagnostic yields among bronchoscopic sampling techniques in the diagnosis of peripheral pulmonary lesions (PPLs). A prospective study was conducted on 112 patients who were diagnosed with PPLs and underwent R-EBUS-guided FB between Oct 2012 and Sep 2014. Sampling techniques-including transbronchial biopsy (TBB), brushing cell block, brushing smear, rinsed fluid of brushing, and bronchoalveolar lavage (BAL)-were evaluated for the diagnosis. The mean diameter of the PPLs was 23.5±9.5 mm. The final diagnoses included 76 malignancies and 36 benign lesions. The overall diagnostic yield of R-EBUS-guided bronchoscopy was 80.4%; TBB gave the highest yield among the 112 specimens: 70.5%, 34.8%, 62.5%, 50.0% and 42.0% for TBB, brushing cell block, brushing smear, rinsed brushing fluid, and BAL fluid (BALF), respectively (P<0.001). TBB provided high diagnostic yield irrespective of the size and etiology of the PPLs. The combination of TBB and brushing smear achieved the maximum diagnostic yield. Of 31 infectious PPLs, BALF culture gave additional microbiological information in 20 cases. TBB provided the highest diagnostic yield; however, to achieve the highest diagnostic performance, TBB, brushing smear and BAL techniques should be performed together.
-
Lewiss, Resa E; Chan, Wilma; Sheng, Alexander Y; Soto, Jorge; Castro, Alexandra; Meltzer, Andrew C; Cherney, Alan; Kumaravel, Manickam; Cody, Dianna; Chen, Esther H
2015-12-01
The appropriate selection and accurate interpretation of diagnostic imaging is a crucial skill for emergency practitioners. To date, the majority of the published literature and research on competency assessment comes from the subspecialty of point-of-care ultrasound. A group of radiologists, physicists, and emergency physicians convened at the 2015 Academic Emergency Medicine consensus conference to discuss and prioritize a research agenda related to education, assessment, and competency in ordering and interpreting diagnostic imaging. A set of questions for the continued development of an educational curriculum on diagnostic imaging for trainees and competency assessment using specific assessment methods based on current best practices was delineated. The research priorities were developed through an iterative consensus-driven process using a modified nominal group technique that culminated in an in-person breakout session. The four recommendations are: 1) develop a diagnostic imaging curriculum for emergency medicine (EM) residency training; 2) develop, study, and validate tools to assess competency in diagnostic imaging interpretation; 3) evaluate the role of simulation in education, assessment, and competency measures for diagnostic imaging; 4) study is needed regarding the American College of Radiology Appropriateness Criteria, an evidence-based peer-reviewed resource in determining the use of diagnostic imaging, to maximize its value in EM. In this article, the authors review the supporting reliability and validity evidence and make specific recommendations for future research on the education, competency, and assessment of learning diagnostic imaging. © 2015 by the Society for Academic Emergency Medicine.
-
Siddique, Iqbal; Mohan, Krishna; Hasan, Fuad; Memon, Anjum; Patty, Istvan; Al-Nakib, Basil
2005-11-28
To assess the appropriateness of referrals and to determine the diagnostic yield of colonoscopy according to the 2000 guidelines of the American Society for Gastrointestinal Endoscopy (ASGE). A total of 736 consecutive patients (415 males, 321 females; mean age 43.6+/-16.6 years) undergoing colonoscopy during October 2001-March 2002 were prospectively enrolled in the study. The 2000 ASGE guidelines were used to assess the appropriateness of the indications for the procedure. Diagnostic yield was defined as the ratio between significant findings detected on colonoscopy and the total number of procedures performed for that indication. The large majority (64%) of patients had colonoscopy for an indication that was considered "generally indicated", it was "generally not indicated" for 20%, and it was "not listed" for 16% in the guidelines. The diagnostic yield of colonoscopy was highest for the "generally indicated" (38%) followed by "not listed" (13%) and "generally not indicated" (5%) categories. In the multivariable analysis, the diagnostic yield was independently associated with the appropriateness of indication that was "generally indicated" (odds ratio=12.3) and referrals by gastroenterologist (odds ratio =1.9). There is a high likelihood of inappropriate referrals for colonoscopy in an open-access endoscopy system. The diagnostic yield of the procedure is dependent on the appropriateness of indication and referring physician's specialty. Certain indications "not listed" in the guidelines have an intermediate diagnostic yield and further studies are required to evaluate whether they should be included in future revisions of the ASGE guidelines.
-
Petranovic, Milena; Gilman, Matthew D; Muniappan, Ashok; Hasserjian, Robert P; Digumarthy, Subba R; Muse, Victorine V; Sharma, Amita; Shepard, Jo-Anne O; Wu, Carol C
2015-10-01
The purpose of this study was to evaluate the diagnostic yield and accuracy of CT-guided percutaneous biopsy of anterior mediastinal masses and assess prebiopsy characteristics that may help to select patients with the highest diagnostic yield. Retrospective review of all CT-guided percutaneous biopsies of the anterior mediastinum conducted at our institution from January 2003 through December 2012 was performed to collect data regarding patient demographics, imaging characteristics of biopsied masses, presence of complications, and subsequent surgical intervention or medical treatment (or both). Cytology, core biopsy pathology, and surgical pathology results were recorded. A per-patient analysis was performed using two-tailed t test, Fisher's exact test, and Pearson chi-square test. The study cohort included 52 patients (32 men, 20 women; mean age, 49 years) with mean diameter of mediastinal mass of 6.9 cm. Diagnostic yield of CT-guided percutaneous biopsy was 77% (40/52), highest for thymic neoplasms (100% [11/11]). Non-diagnostic results were seen in 12 of 52 patients (23%), primarily in patients with lymphoma (75% [9/12]). Fine-needle aspiration yielded the correct diagnosis in 31 of 52 patients (60%), and core biopsy had a diagnostic rate of 77% (36/47). None of the core biopsies were discordant with surgical pathology. There was no statistically significant difference between the diagnostic and the nondiagnostic groups in patient age, lesion size, and presence of necrosis. The complication rate was 3.8% (2/52), all small self-resolving pneumothoraces. CT-guided percutaneous biopsy is a safe diagnostic procedure with high diagnostic yield (77%) for anterior mediastinal lesions, highest for thymic neoplasms (100%), and can potentially obviate more invasive procedures.
-
Diagnostic Yield of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration
2011-01-01
Background: New transbronchial needle aspiration (TBNA) technologies have been developed, but their clinical effectiveness and determinants of diagnostic yield have not been quantified. Prospective data are needed to determine risk-adjusted diagnostic yield. Methods: We prospectively enrolled patients undergoing TBNA of mediastinal lymph nodes in the American College of Chest Physicians Quality Improvement Registry, Evaluation, and Education (AQuIRE) multicenter database and recorded clinical, procedural, and provider information. All clinical decisions, including type of TBNA used (conventional vs endobronchial ultrasound-guided), were made by the attending bronchoscopist. The primary outcome was obtaining a specific diagnosis. Results: We enrolled 891 patients at six hospitals. Most procedures (95%) were performed with ultrasound guidance. A specific diagnosis was made in 447 cases. Unadjusted diagnostic yields were 37% to 54% for different hospitals, with significant between-hospital heterogeneity (P = .0001). Diagnostic yield was associated with annual hospital TBNA volume (OR, 1.003; 95% CI, 1.000-1.006; P = .037), smoking (OR, 1.55; 95% CI, 1.02-2.34; P = .042), biopsy of more than two sites (OR, 0.57; 95% CI, 0.38-0.85; P = .015), lymph node size (reference > 1-2 cm, ≤ 1 cm: OR, 0.51; 95% CI, 0.34-0.77; P = .003; > 2-3 cm: OR, 2.49; 95% CI, 1.61-3.85; P < .001; and > 3 cm: OR, 3.61; 95% CI, 2.17-6.00; P < .001), and positive PET scan (OR, 3.12; 95% CI, 1.39-7.01; P = .018). Biopsy was performed on more and smaller nodes at high-volume hospitals (P < .0001). Conclusions: To our knowledge, this is the first bronchoscopy study of risk-adjusted diagnostic yields on a hospital-level basis. High-volume hospitals were associated with high diagnostic yields. This study also demonstrates the value of procedural registries as a quality improvement tool. A larger number and variety of participating hospitals is needed to verify these results and to further investigate other determinants of diagnostic yield. PMID:21659432
-
Promsuwicha, Orathai; Kankhao, Supattra; Songmuang, Wayuree; Auewarakul, Chirayu U
2014-12-01
Diagnosis of hematologic malignancies requires a multidisciplinary approach. Flow cytometry (FCM) has become an essential tool for immunophenotypic studies of malignant hematopoietic cells. To evaluate the utilization trend of FCM and its diagnostic yields for hematologic malignancy at a major teaching hospital in Thailand. FCM results of bone marrow (BM) and peripheral blood (PB) specimens during 2000-2013 were analyzed and compared to clinical diagnosis. Overall, 7,982 specimens were submitted for diagnostic FCM including 6,561 BM and 1,421 PB. The number of specimens analyzedwas 121, 142, 164, 299, 491, 431, 690, 611, 719, 744, 725, 863, 955 and 1,027, respectively, from 2000 to 2013. The most common clinical diagnoses requested for FCM were acute leukemia (5,911 cases, 74%) followed by lymphoma (1,419 cases, 17.8%), and chronic lymphocytic leukemia (CLL) (634 cases, 7.94%). The highest diagnostic yield of FCM was found in acute leukemia cases (69.71%) followed by CLL (35.33%). Only 15.43% of clinically suspected lymphoma cases were positive by FCM. Overutilization of PB (35.6% of cases) instead of BM for lymphoma staging significantly contributed to low diagnostic yields of lymphoma by FCM as circulating tumor cells may not be present in such cases. FCM has an increasing role in the diagnosis of hematologic malignancies in Thai patients over the past 14 years with the highest diagnostic yield in acute leukemia. Appropriate specimen types and study indications are required in order to reduce futility of costly diagnostic tests and improve diagnostic yields.
-
Lennon, Anne Marie; Kapoor, Sumit; Khashab, Mouen; Corless, Erin; Amateau, Stuart; Dunbar, Kerry; Chandrasekhara, Vinay; Singh, Vikesh; Okolo, Patrick I
2012-05-01
Endoscopic retrograde cholangiopancreatography (ERCP) is often unsuccessful in patients with Roux-en-Y anatomy. Augmented enteroscopy allows deep insertion into the small bowel and can be useful in patients with Roux-en-Y anatomy. The aim of this study was to compare single balloon assisted ERCP (SBE-ERCP) and spiral assisted ERCP (SE-ERCP) in patients with Roux-en-Y anatomy in terms of diagnostic and therapeutic yield, procedure time, and complications. This is a retrospective cohort study of consecutive patients with Roux-en-Y anatomy who underwent SBE-ERCP or SE-ERCP between October 2007 and March 2011. Diagnostic yield was defined as successful duct cannulation. Therapeutic yield was defined as the ability to successfully carry out endoscopic therapy in those cannulated. Procedure time and complications were assessed. Thirty-four consecutive patients with Roux-en-Y anatomy underwent 54 ERCP procedures. The overall diagnostic yield was 44.4% with no significant difference between the diagnostic yield of SBE-ERCP (48.3%) and SE-ERCP (40%). The diagnostic yield was lower in patients with gastric by-pass (38.9%) compared with other types of Roux-en-Y anatomy (47.2%) but this was not statistically significant (P = 0.772). The overall therapeutic yield was 93.8%, with a therapeutic yield of 100% for SBE-ERCP and 87.5% for SE-ERCP (P = 1.0). There was one perforation during SBE-ERCP, giving a complication rate of 3.5%. The mean procedure time did not differ between the two techniques. Diagnostic and therapeutic yields are similar with SBE-ERCP and SE-ERCP in patients with Roux-en-Y anatomy with no significant difference in procedure time or complication rates.
-
Radiological interpretation of images displayed on tablet computers: a systematic review.
Caffery, L J; Armfield, N R; Smith, A C
2015-06-01
To review the published evidence and to determine if radiological diagnostic accuracy is compromised when images are displayed on a tablet computer and thereby inform practice on using tablet computers for radiological interpretation by on-call radiologists. We searched the PubMed and EMBASE databases for studies on the diagnostic accuracy or diagnostic reliability of images interpreted on tablet computers. Studies were screened for inclusion based on pre-determined inclusion and exclusion criteria. Studies were assessed for quality and risk of bias using Quality Appraisal of Diagnostic Reliability Studies or the revised Quality Assessment of Diagnostic Accuracy Studies tool. Treatment of studies was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). 11 studies met the inclusion criteria. 10 of these studies tested the Apple iPad(®) (Apple, Cupertino, CA). The included studies reported high sensitivity (84-98%), specificity (74-100%) and accuracy rates (98-100%) for radiological diagnosis. There was no statistically significant difference in accuracy between a tablet computer and a digital imaging and communication in medicine-calibrated control display. There was a near complete consensus from authors on the non-inferiority of diagnostic accuracy of images displayed on a tablet computer. All of the included studies were judged to be at risk of bias. Our findings suggest that the diagnostic accuracy of radiological interpretation is not compromised by using a tablet computer. This result is only relevant to the Apple iPad and to the modalities of CT, MRI and plain radiography. The iPad may be appropriate for an on-call radiologist to use for radiological interpretation.
-
2010-01-01
Background Abnormal results of diagnostic laboratory tests can be difficult to interpret when disease probability is very low. Although most physicians generally do not use Bayesian calculations to interpret abnormal results, their estimates of pretest disease probability and reasons for ordering diagnostic tests may - in a more implicit manner - influence test interpretation and further management. A better understanding of this influence may help to improve test interpretation and management. Therefore, the objective of this study was to examine the influence of physicians' pretest disease probability estimates, and their reasons for ordering diagnostic tests, on test result interpretation, posttest probability estimates and further management. Methods Prospective study among 87 primary care physicians in the Netherlands who each ordered laboratory tests for 25 patients. They recorded their reasons for ordering the tests (to exclude or confirm disease or to reassure patients) and their pretest disease probability estimates. Upon receiving the results they recorded how they interpreted the tests, their posttest probability estimates and further management. Logistic regression was used to analyse whether the pretest probability and the reasons for ordering tests influenced the interpretation, the posttest probability estimates and the decisions on further management. Results The physicians ordered tests for diagnostic purposes for 1253 patients; 742 patients had an abnormal result (64%). Physicians' pretest probability estimates and their reasons for ordering diagnostic tests influenced test interpretation, posttest probability estimates and further management. Abnormal results of tests ordered for reasons of reassurance were significantly more likely to be interpreted as normal (65.8%) compared to tests ordered to confirm a diagnosis or exclude a disease (27.7% and 50.9%, respectively). The odds for abnormal results to be interpreted as normal were much lower when the physician estimated a high pretest disease probability, compared to a low pretest probability estimate (OR = 0.18, 95% CI = 0.07-0.52, p < 0.001). Conclusions Interpretation and management of abnormal test results were strongly influenced by physicians' estimation of pretest disease probability and by the reason for ordering the test. By relating abnormal laboratory results to their pretest expectations, physicians may seek a balance between over- and under-reacting to laboratory test results. PMID:20158908
-
Houben, Paul H H; van der Weijden, Trudy; Winkens, Bjorn; Winkens, Ron A G; Grol, Richard P T M
2010-02-16
Abnormal results of diagnostic laboratory tests can be difficult to interpret when disease probability is very low. Although most physicians generally do not use Bayesian calculations to interpret abnormal results, their estimates of pretest disease probability and reasons for ordering diagnostic tests may--in a more implicit manner--influence test interpretation and further management. A better understanding of this influence may help to improve test interpretation and management. Therefore, the objective of this study was to examine the influence of physicians' pretest disease probability estimates, and their reasons for ordering diagnostic tests, on test result interpretation, posttest probability estimates and further management. Prospective study among 87 primary care physicians in the Netherlands who each ordered laboratory tests for 25 patients. They recorded their reasons for ordering the tests (to exclude or confirm disease or to reassure patients) and their pretest disease probability estimates. Upon receiving the results they recorded how they interpreted the tests, their posttest probability estimates and further management. Logistic regression was used to analyse whether the pretest probability and the reasons for ordering tests influenced the interpretation, the posttest probability estimates and the decisions on further management. The physicians ordered tests for diagnostic purposes for 1253 patients; 742 patients had an abnormal result (64%). Physicians' pretest probability estimates and their reasons for ordering diagnostic tests influenced test interpretation, posttest probability estimates and further management. Abnormal results of tests ordered for reasons of reassurance were significantly more likely to be interpreted as normal (65.8%) compared to tests ordered to confirm a diagnosis or exclude a disease (27.7% and 50.9%, respectively). The odds for abnormal results to be interpreted as normal were much lower when the physician estimated a high pretest disease probability, compared to a low pretest probability estimate (OR = 0.18, 95% CI = 0.07-0.52, p < 0.001). Interpretation and management of abnormal test results were strongly influenced by physicians' estimation of pretest disease probability and by the reason for ordering the test. By relating abnormal laboratory results to their pretest expectations, physicians may seek a balance between over- and under-reacting to laboratory test results.
-
Siddique, Iqbal; Mohan, Krishna; Hasan, Fuad; Memon, Anjum; Patty, Istvan; Al-Nakib, Basil
2005-01-01
AIM: To assess the appropriateness of referrals and to determine the diagnostic yield of colonoscopy according to the 2000 guidelines of the American Society for Gastrointestinal Endoscopy (ASGE). METHODS: A total of 736 consecutive patients (415 males, 321 females; mean age 43.6±16.6 years) undergoing colonoscopy during October 2001-March 2002 were prospectively enrolled in the study. The 2000 ASGE guidelines were used to assess the appropriateness of the indications for the procedure. Diagnostic yield was defined as the ratio between significant findings detected on colonoscopy and the total number of procedures performed for that indication. RESULTS: The large majority (64%) of patients had colonoscopy for an indication that was considered “generally indicated”, it was “generally not indicated” for 20%, and it was “not listed” for 16% in the guidelines. The diagnostic yield of colonoscopy was highest for the “generally indicated” (38%) followed by “not listed” (13%) and “generally not indicated” (5%) categories. In the multivariable analysis, the diagnostic yield was independently associated with the appropriateness of indication that was “generally indicated” (odds ratio=12.3) and referrals by gastroenterologist (odds ratio =1.9). CONCLUSION: There is a high likelihood of inappropriate referrals for colonoscopy in an open-access endoscopy system. The diagnostic yield of the procedure is dependent on the appropriateness of indication and referring physician’s specialty. Certain indications “not listed” in the guidelines have an intermediate diagnostic yield and further studies are required to evaluate whether they should be included in future revisions of the ASGE guidelines. PMID:16437607
-
(18)F-FDG uptake predicts diagnostic yield of transbronchial biopsy in peripheral lung cancer.
Umeda, Yukihiro; Demura, Yoshiki; Anzai, Masaki; Matsuoka, Hiroki; Araya, Tomoyuki; Nishitsuji, Masaru; Nishi, Koichi; Tsuchida, Tatsuro; Sumida, Yasuyuki; Morikawa, Miwa; Ameshima, Shingo; Ishizaki, Takeshi; Kasahara, Kazuo; Ishizuka, Tamotsu
2014-07-01
Recent advances in endobronchial ultrasonography with a guide sheath (EBUS-GS) have enabled better visualization of distal airways, while virtual bronchoscopic navigation (VBN) has been shown useful as a guide to navigate the bronchoscope. However, indications for utilizing VBN and EBUS-GS are not always clear. To clarify indications for a bronchoscopic examination using VBN and EBUS-GS, we evaluated factors that predict the diagnostic yield of a transbronchial biopsy (TBB) procedure for peripheral lung cancer (PLC) lesions. We retrospectively reviewed the charts of 194 patients with 201 PLC lesions (≤3cm mean diameter), and analyzed the association of diagnostic yield of TBB with [(18)F]-fluoro-2-deoxy-d-glucose ((18)F-FDG) positron emission tomography and chest computed tomography (CT) findings. The diagnostic yield of TBB using VBN and EBUS-GS was 66.7%. High maximum standardized uptake value (SUVmax), positive bronchus sign, and ground-glass opacity component shown on CT were all significant predictors of diagnostic yield, while multivariate analysis showed only high (18)F-FDG uptake (SUVmax ≥2.8) and positive bronchus sign as significant predictors. Diagnostic yield was higher for PLC lesions with high (18)F-FDG uptake (SUVmax ≥2.8) and positive bronchus sign (84.6%) than for those with SUVmax <2.8 and negative bronchus sign (33.3%). High (18)F-FDG uptake was also correlated with tumor invasiveness. High (18)F-FDG uptake predicted the diagnostic yield of TBB using VBN and EBUS-GS for PLC lesions. (18)F-FDG uptake and bronchus sign may indicate for the accurate application of bronchoscopy with those modalities for diagnosing PLC. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
-
21 CFR 868.1900 - Diagnostic pulmonary-function interpretation calculator.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Diagnostic pulmonary-function interpretation calculator. 868.1900 Section 868.1900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... pulmonary-function values. (b) Classification. Class II (performance standards). ...
-
21 CFR 868.1900 - Diagnostic pulmonary-function interpretation calculator.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Diagnostic pulmonary-function interpretation calculator. 868.1900 Section 868.1900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... pulmonary-function values. (b) Classification. Class II (performance standards). ...
-
Yan, Lei; Ikemura, Kenji; Park, Ji-Weon
2018-02-01
Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided core-needle biopsy (EUS-CNB) are widely used for diagnosis of pancreatic tumors. The aim of our study was to compare the diagnostic performance of ROSE EUS-FNA and EUS-CNB for diagnosis of pancreatic malignancy during the same EUS. Patients who underwent both FNA and CNB during the same EUS for pancreatic solid lesion were reviewed retrospectively. Sample adequacy, diagnostic yield (defined as percentage of definitive diagnosis), sensitivity and specificity for malignancy were compared between FNA and CNB. A total of 48 patients with solid pancreatic lesions were evaluated. The proportions of adequate samples were 48/48 (100%) for FNA and 45/48 (93.7%) for core biopsy (P = .24). The diagnostic yield was 42/48 (87.5%) and 33/48 (68.7%) for FNA and CNB respectively (P = .046). The incremental increase in diagnostic yield by combining both methods was 2/48 (4%). The diagnostic yield for malignancy was 30/32 (93.7%) for FNA and 23/32 (71.8%) for CNB (P = .043). The sensitivity for the diagnosis of malignancy for FNA and CNB were 90.6% and 69%, respectively (P = .045). The specificity was 100% for both methods. The sensitivity for diagnosing malignancy increased to 93.8% when the two methods were combined. The difference in diagnostic yield was not associated with lesion size or location. EUS-guided FNA is a superior method of assessing solid pancreatic lesion and pancreatic malignancy with better diagnostic yield and higher sensitivity than EUS-CNB. © 2017 Wiley Periodicals, Inc.
-
Use of an Additional 19-G EBUS-TBNA Needle Increases the Diagnostic Yield of EBUS-TBNA.
Garrison, Garth; Leclair, Timothy; Balla, Agnes; Wagner, Sarah; Butnor, Kelly; Anderson, Scott R; Kinsey, C Matthew
2018-06-12
Although endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has an excellent diagnostic yield, there remain cases where the diagnosis is not obtained. We hypothesized that additional sampling with a 19-G EBUS-TBNA needle may increase diagnostic yield in a subset of cases where additional tissue sampling was required. Indications for use of the 19-G needle following 22-G sampling with rapid on-site cytologic examination were: (1) diagnostic uncertainty of the on-site cytopathologist (eg, nondiagnostic, probable lymphoma, etc.), (2) non-small cell lung cancer with probable need for molecular genetic and/or PD-L1 testing, or (3) need for a larger tissue sample for consideration of inclusion in a research protocol. A 19-G EBUS-TBNA needle was utilized following standard sampling with a 22-G needle in 48 patients (50 sites) during the same procedure. Although the diagnostic yield between the needles was equivalent, the concordance rate was only 83%. The 19-G determined a diagnosis in 4 additional patients (8%) and provided additional histopathologic information in 6 other cases (12%). Conversely, in 3 cases (6%) diagnostic information was provided only by the 22-G needle. Compared with 22-G EBUS-TBNA alone, sampling with both the 22- and 19-G EBUS needles resulted in an increase in diagnostic yield from 92% to 99% (P=0.045) and a number needed to sample of 13 patients to provide one additional diagnosis. There were no significant complications. In select cases where additional tissue may be needed, sampling with a 19-G EBUS needle following standard aspiration with a 22-G needle results in an increase in diagnostic yield.
-
Interventional radiology; Diagnostic radiology; X-ray imaging ... DIAGNOSTIC RADIOLOGY Diagnostic radiology helps health care professionals see structures inside your body. Doctors that specialize in the interpretation ...
-
Multiomics tools for the diagnosis and treatment of rare neurological disease.
Crowther, L M; Poms, M; Plecko, Barbara
2018-05-01
Conventional workup of rare neurological disease is frequently hampered by diagnostic delay or lack of diagnosis. While biomarkers have been established for many neurometabolic disorders, improved methods are required for diagnosis of previously unidentified or underreported causes of rare neurological disease. This would result in a higher diagnostic yield and increased patient numbers required for interventional studies. Recent studies using next-generation sequencing and metabolomics have led to identification of novel disease-causing genes and biomarkers. This combined approach can assist in overcoming challenges associated with analyzing and interpreting the large amount of data obtained from each technique. In particular, metabolomics can support the pathogenicity of sequence variants in genes encoding enzymes or transporters involved in metabolic pathways. Moreover, metabolomics can show the broader perturbation caused by inborn errors of metabolism and identify a metabolic fingerprint of metabolic disorders. As such, using "omics" has great potential to meet the current needs for improved diagnosis and elucidation of rare neurological disease.
-
Radiological interpretation of images displayed on tablet computers: a systematic review
Armfield, N R; Smith, A C
2015-01-01
Objective: To review the published evidence and to determine if radiological diagnostic accuracy is compromised when images are displayed on a tablet computer and thereby inform practice on using tablet computers for radiological interpretation by on-call radiologists. Methods: We searched the PubMed and EMBASE databases for studies on the diagnostic accuracy or diagnostic reliability of images interpreted on tablet computers. Studies were screened for inclusion based on pre-determined inclusion and exclusion criteria. Studies were assessed for quality and risk of bias using Quality Appraisal of Diagnostic Reliability Studies or the revised Quality Assessment of Diagnostic Accuracy Studies tool. Treatment of studies was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Results: 11 studies met the inclusion criteria. 10 of these studies tested the Apple iPad® (Apple, Cupertino, CA). The included studies reported high sensitivity (84–98%), specificity (74–100%) and accuracy rates (98–100%) for radiological diagnosis. There was no statistically significant difference in accuracy between a tablet computer and a digital imaging and communication in medicine-calibrated control display. There was a near complete consensus from authors on the non-inferiority of diagnostic accuracy of images displayed on a tablet computer. All of the included studies were judged to be at risk of bias. Conclusion: Our findings suggest that the diagnostic accuracy of radiological interpretation is not compromised by using a tablet computer. This result is only relevant to the Apple iPad and to the modalities of CT, MRI and plain radiography. Advances in knowledge: The iPad may be appropriate for an on-call radiologist to use for radiological interpretation. PMID:25882691
-
An evaluation of consensus techniques for diagnostic interpretation
NASA Astrophysics Data System (ADS)
Sauter, Jake N.; LaBarre, Victoria M.; Furst, Jacob D.; Raicu, Daniela S.
2018-02-01
Learning diagnostic labels from image content has been the standard in computer-aided diagnosis. Most computer-aided diagnosis systems use low-level image features extracted directly from image content to train and test machine learning classifiers for diagnostic label prediction. When the ground truth for the diagnostic labels is not available, reference truth is generated from the experts diagnostic interpretations of the image/region of interest. More specifically, when the label is uncertain, e.g. when multiple experts label an image and their interpretations are different, techniques to handle the label variability are necessary. In this paper, we compare three consensus techniques that are typically used to encode the variability in the experts labeling of the medical data: mean, median and mode, and their effects on simple classifiers that can handle deterministic labels (decision trees) and probabilistic vectors of labels (belief decision trees). Given that the NIH/NCI Lung Image Database Consortium (LIDC) data provides interpretations for lung nodules by up to four radiologists, we leverage the LIDC data to evaluate and compare these consensus approaches when creating computer-aided diagnosis systems for lung nodules. First, low-level image features of nodules are extracted and paired with their radiologists semantic ratings (1= most likely benign, , 5 = most likely malignant); second, machine learning multi-class classifiers that handle deterministic labels (decision trees) and probabilistic vectors of labels (belief decision trees) are built to predict the lung nodules semantic ratings. We show that the mean-based consensus generates the most robust classi- fier overall when compared to the median- and mode-based consensus. Lastly, the results of this study show that, when building CAD systems with uncertain diagnostic interpretation, it is important to evaluate different strategies for encoding and predicting the diagnostic label.
-
Lu, Yi; Yeung, Cecil; Radmanesh, Alireza; Wiemann, Robert; Black, Peter M.; Golby, Alexandra J.
2015-01-01
Objective Intraoperative MRI (IoMRI) guided brain biopsy provides a real time visual feedback of the lesion that is sampled during surgery. The objective of the study is to compare the diagnostic yield and safety profiles of ioMRI needle brain biopsy with two traditional brain biopsy methods: frame-based and frameless stereotactic brain biopsies. Methods A retrospective analysis from 288 consecutive needle brain biopsies in 277 patients undergoing stereotactic brain biopsy with any of the three biopsy methods at Brigham and Women's Hospital from 2000 to 2008 was performed. Variables such as age, sex, history of radiation and previous surgery, pathology results, complications and postoperative stays were analyzed. Results Over the course of eight years, 288 brain biopsies were performed. 253 (87.8%) biopsies yielded positive diagnostic tissue. Young age (<40 years), history of brain radiation or surgery were significant negative predictors for a positive biopsy diagnostic yield. Excluding patients with prior radiation or surgeries, no significant difference in diagnostic yield was detected among the three groups, with frame-based, frameless and ioMRI guided needle biopsies yield 96.9%, 91.8% and 89.9% positive diagnostic yield, respectively. 19 biopsies (6.6%) were complicated by serious adverse events. The ioMRI-guided brain biopsy was associated with less serious adverse events and the shortest postoperative hospital stay. Conclusions Frame-based, frameless stereotactic and ioMRI guided brain needle biopsy have comparable diagnostic yield for patients with no prior treatments (either radiation or surgery). IoMRI guided brain biopsy is associated with fewer serious adverse events and shorter hospital stay. PMID:25088233
-
Quinn, S F; Neubauer, N M; Sheley, R C; Demlow, T A; Szumowski, J
1996-01-01
MR imaging was used to evaluate the integrity of silicone breast implants in 54 women with 108 implants. MR images were interpreted by relatively inexperienced readers who tried to reproduce the experiences reported in the literature. The study examines the interobserver agreement using different diagnostic signs and the influence of experience on interpretation errors. Prospective and retrospective interpretations were compared with surgical findings at the time of explanation. Diagnostic indicators, including the linguine sign, the inverted tear drop sign, the C sign, water droplets mixed with silicone, and extracapsular globules of silicone, were evaluated for diagnostic efficacy and interobserver agreement. The prospective sensitivity and specificity were 87% and 78%, respectively. With the retrospective interpretations, the sensitivity and specificity increased to 93% and 92%, respectively. Most of the prospective false-positive interpretations were due to misinterpreting radial folds as signs of implant rupture. Six implants interpreted retrospectively as false positives had gross amounts of silicone around the implants at surgery but there were no obvious rents in the implant shells. There was fair to excellent interobserver agreement with the individual diagnostic signs except for extracapsular globules of silicone. All of the signs had specificities of greater than 90%. The sensitivities of the individual signs were less than the overall retrospective sensitivity. With experience, the sensitivity improved from 87% to 93% and the specificity improved from 78% to 92%. This study helps substantiate the use of diagnostic signs used by other authors to detect silicone loss from breast implants by MR imaging; however, questions remain as to the clinical role of MR imaging in evaluating implants for silicone loss.
-
ADHD Rating Scale-IV: Checklists, Norms, and Clinical Interpretation
ERIC Educational Resources Information Center
Pappas, Danielle
2006-01-01
This article reviews the "ADHD Rating Scale-IV: Checklist, norms, and clinical interpretation," is a norm-referenced checklist that measures the symptoms of attention deficit/hyperactivity disorder (ADHD) according to the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric…
-
Nitzsche, Björn; Lobsien, Donald; Seeger, Johannes; Schneider, Holm; Boltze, Johannes
2014-01-01
Cerebrovascular diseases are significant causes of death and disability in humans. Improvements in diagnostic and therapeutic approaches strongly rely on adequate gyrencephalic, large animal models being demanded for translational research. Ovine stroke models may represent a promising approach but are currently limited by insufficient knowledge regarding the venous system of the cerebral angioarchitecture. The present study was intended to provide a comprehensive anatomical analysis of the intracranial venous system in sheep as a reliable basis for the interpretation of experimental results in such ovine models. We used corrosion casts as well as contrast-enhanced magnetic resonance venography to scrutinize blood drainage from the brain. This combined approach yielded detailed and, to some extent, novel findings. In particular, we provide evidence for chordae Willisii and lateral venous lacunae, and report on connections between the dorsal and ventral sinuses in this species. For the first time, we also describe venous confluences in the deep cerebral venous system and an ‘anterior condylar confluent’ as seen in humans. This report provides a detailed reference for the interpretation of venous diagnostic imaging findings in sheep, including an assessment of structure detectability by in vivo (imaging) versus ex vivo (corrosion cast) visualization methods. Moreover, it features a comprehensive interspecies-comparison of the venous cerebral angioarchitecture in man, rodents, canines and sheep as a relevant large animal model species, and describes possible implications for translational cerebrovascular research. PMID:24736654
-
NASA Astrophysics Data System (ADS)
De Boissieu, Florian; Sevin, Brice; Cudahy, Thomas; Mangeas, Morgan; Chevrel, Stéphane; Ong, Cindy; Rodger, Andrew; Maurizot, Pierre; Laukamp, Carsten; Lau, Ian; Touraivane, Touraivane; Cluzel, Dominique; Despinoy, Marc
2018-02-01
Accurate maps of Earth's geology, especially its regolith, are required for managing the sustainable exploration and development of mineral resources. This paper shows how airborne imaging hyperspectral data collected over weathered peridotite rocks in vegetated, mountainous terrane in New Caledonia were processed using a combination of methods to generate a regolith-geology map that could be used for more efficiently targeting Ni exploration. The image processing combined two usual methods, which are spectral feature extraction and support vector machine (SVM). This rationale being the spectral features extraction can rapidly reduce data complexity by both targeting only the diagnostic mineral absorptions and masking those pixels complicated by vegetation, cloud and deep shade. SVM is a supervised classification method able to generate an optimal non-linear classifier with these features that generalises well even with limited training data. Key minerals targeted are serpentine, which is considered as an indicator for hydrolysed peridotitic rock, and iron oxy-hydroxides (hematite and goethite), which are considered as diagnostic of laterite development. The final classified regolith map was assessed against interpreted regolith field sites, which yielded approximately 70% similarity for all unit types, as well as against a regolith-geology map interpreted using traditional datasets (not hyperspectral imagery). Importantly, the hyperspectral derived mineral map provided much greater detail enabling a more precise understanding of the regolith-geological architecture where there are exposed soils and rocks.
-
Vij, Abhinav; Seale, Melanie K.; Desai, Gaurav; Halpern, Elkan; Faquin, William C.; Parangi, Sareh; Hahn, Peter F.; Daniels, Gilbert H.
2012-01-01
Background Five percent to 20% of thyroid nodule fine-needle aspiration (FNA) samples are nondiagnostic. The objective of this study was to determine whether a combination of FNA and core biopsy (CFNACB) would yield a higher proportion of diagnostic readings compared with FNA alone in patients with a history of one or more prior nondiagnostic FNA readings. Methods We conducted a retrospective study of 90 core biopsies (CBs) performed in 82 subjects (55 women and 27 men) between 2006 and 2008 in an outpatient clinic. Results CFNACB yielded a diagnostic reading in 87%. The diagnostic reading yield of the CB component of CFNACB was significantly superior to the concurrent FNA component, with CB yielding a diagnosis in 77% of cases and FNA yielding a diagnosis in 47% (p<0.0001). The combination of CB and FNA had a higher diagnostic reading yield than either alone. In 69 nodules that had only one prior nondiagnostic FNA, CB was diagnostic in 74%, FNA was diagnostic in 52%, CFNACB was diagnostic in 87%, and CB performed significantly better than FNA (p=0.0135). In 21 nodules with two or more prior nondiagnostic FNAs, CFNACB and CB were diagnostic in 86%, FNA was diagnostic in 29%, and CB was significantly better than FNA (p=0.0005). Clinical, ultrasound, or histopathologic follow-up was available for 81% (73/90) of the CFNACB procedures. No subject with a benign CFNACB reading was diagnosed with thyroid malignancy in the follow-up period (range 4–37 months, mean 18 months), although one subject had minimal increase in nodule size and was awaiting repeat sonography at study conclusion. Conclusion Thyroid nodule CFNACB is safe and clinically useful in selected patients when a prior FNA reading is nondiagnostic. CFNACB is superior to either CB or FNA alone. CFNACB should be strongly considered as an alternative to surgery in individuals with two prior nondiagnostic FNAs. PMID:22304390
-
Mc Laughlin, Patrick; Neill, Siobhan O; Fanning, Noel; Mc Garrigle, Anne Marie; Connor, Owen J O; Wyse, Gerry; Maher, Michael M
2012-04-01
Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.
-
Mason, Jay W; Hancock, E William; Gettes, Leonard S
2007-03-01
This statement provides a concise list of diagnostic terms for ECG interpretation that can be shared by students, teachers, and readers of electrocardiography. This effort was motivated by the existence of multiple automated diagnostic code sets containing imprecise and overlapping terms. An intended outcome of this statement list is greater uniformity of ECG diagnosis and a resultant improvement in patient care. The lexicon includes primary diagnostic statements, secondary diagnostic statements, modifiers, and statements for the comparison of ECGs. This diagnostic lexicon should be reviewed and updated periodically.
-
Cairns, Andrew W; Bond, Raymond R; Finlay, Dewar D; Breen, Cathal; Guldenring, Daniel; Gaffney, Robert; Gallagher, Anthony G; Peace, Aaron J; Henn, Pat
2016-12-01
The 12-lead Electrocardiogram (ECG) presents a plethora of information and demands extensive knowledge and a high cognitive workload to interpret. Whilst the ECG is an important clinical tool, it is frequently incorrectly interpreted. Even expert clinicians are known to impulsively provide a diagnosis based on their first impression and often miss co-abnormalities. Given it is widely reported that there is a lack of competency in ECG interpretation, it is imperative to optimise the interpretation process. Predominantly the ECG interpretation process remains a paper based approach and whilst computer algorithms are used to assist interpreters by providing printed computerised diagnoses, there are a lack of interactive human-computer interfaces to guide and assist the interpreter. An interactive computing system was developed to guide the decision making process of a clinician when interpreting the ECG. The system decomposes the interpretation process into a series of interactive sub-tasks and encourages the clinician to systematically interpret the ECG. We have named this model 'Interactive Progressive based Interpretation' (IPI) as the user cannot 'progress' unless they complete each sub-task. Using this model, the ECG is segmented into five parts and presented over five user interfaces (1: Rhythm interpretation, 2: Interpretation of the P-wave morphology, 3: Limb lead interpretation, 4: QRS morphology interpretation with chest lead and rhythm strip presentation and 5: Final review of 12-lead ECG). The IPI model was implemented using emerging web technologies (i.e. HTML5, CSS3, AJAX, PHP and MySQL). It was hypothesised that this system would reduce the number of interpretation errors and increase diagnostic accuracy in ECG interpreters. To test this, we compared the diagnostic accuracy of clinicians when they used the standard approach (control cohort) with clinicians who interpreted the same ECGs using the IPI approach (IPI cohort). For the control cohort, the (mean; standard deviation; confidence interval) of the ECG interpretation accuracy was (45.45%; SD=18.1%; CI=42.07, 48.83). The mean ECG interpretation accuracy rate for the IPI cohort was 58.85% (SD=42.4%; CI=49.12, 68.58), which indicates a positive mean difference of 13.4%. (CI=4.45, 22.35) An N-1 Chi-square test of independence indicated a 92% chance that the IPI cohort will have a higher accuracy rate. Interpreter self-rated confidence also increased between cohorts from a mean of 4.9/10 in the control cohort to 6.8/10 in the IPI cohort (p=0.06). Whilst the IPI cohort had greater diagnostic accuracy, the duration of ECG interpretation was six times longer when compared to the control cohort. We have developed a system that segments and presents the ECG across five graphical user interfaces. Results indicate that this approach improves diagnostic accuracy but with the expense of time, which is a valuable resource in medical practice. Copyright © 2016 Elsevier Inc. All rights reserved.
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ackart, R.S.; Munzel, T.L.; Rodriguez, J.J.
1982-07-01
Nineteen consecutive patients with clinically suspected sarcoidosis underwent /sup 67/Ga-scintigraphy prior to transbronchial lung biopsy (TBLB) to determine if /sup 67/Ga uptake in lung parenchyma would increase the diagnostic yield of the biopsy procedure. Biopsies were obtained from the areas showing parenchymal uptake on the /sup 67/Ga scan in 13 of the 19 patients. In the six patients not demonstrating uptake of /sup 67/Ga in the lung parenchyma, biopsies were obtained at random from the right lower lobe. There was no correlation between /sup 67/Ga uptake in hilar nodes or pulmonary parenchyma tissue and the diagnostic yield from TBLB. Researchersmore » conclude that /sup 67/Ga scanning is neither efficacious nor cost-effective in predicting the diagnostic yield of TBLB in sarcoidosis.« less
-
Iguchi, Toshihiro; Hiraki, Takao; Matsui, Yusuke; Fujiwara, Hiroyasu; Sakurai, Jun; Masaoka, Yoshihisa; Gobara, Hideo; Kanazawa, Susumu
2018-01-01
To evaluate retrospectively the diagnostic yield, safety, and risk factors for diagnostic failure of computed tomography (CT) fluoroscopy-guided renal tumour biopsy. Biopsies were performed for 208 tumours (mean diameter 2.3 cm; median diameter 2.1 cm; range 0.9-8.5 cm) in 199 patients. One hundred and ninety-nine tumours were ≤4 cm. All 208 initial procedures were divided into diagnostic success and failure groups. Multiple variables related to the patients, lesions, and procedures were assessed to determine the risk factors for diagnostic failure. After performing 208 initial and nine repeat biopsies, 180 malignancies and 15 benign tumours were pathologically diagnosed, whereas 13 were not diagnosed. In 117 procedures, 118 Grade I and one Grade IIIa adverse events (AEs) occurred. Neither Grade ≥IIIb AEs nor tumour seeding were observed within a median follow-up period of 13.7 months. Logistic regression analysis revealed only small tumour size (≤1.5 cm; odds ratio 3.750; 95% confidence interval 1.362-10.326; P = 0.011) to be a significant risk factor for diagnostic failure. CT fluoroscopy-guided renal tumour biopsy is a safe procedure with a high diagnostic yield. A small tumour size (≤1.5 cm) is a significant risk factor for diagnostic failure. • CT fluoroscopy-guided renal tumour biopsy has a high diagnostic yield. • CT fluoroscopy-guided renal tumour biopsy is safe. • Small tumour size (≤1.5 cm) is a risk factor for diagnostic failure.
-
Lin, Abraham; Harris, Mitchell; Zalis, Michael
2010-07-01
Electronic medical record (EMR) systems permit integration of contextual nonimaging EMR data into examination interpretation; however, the extra effort required to search and review these nonradiologic data are not well characterized. We assessed the gross frequency and pattern of EMR usage in the interpretation of diagnostic CT and MRI examinations. We defined nonradiologic EMR data as laboratory data, nonimaging specialty report, clinical note, and administrative data not available on PACS. For abdominal, neuroradiologic, and musculoskeletal CT and MRI, we prospectively recorded the time required for image analysis (including prior imaging studies and their reports), nonradiologic EMR use, and initial report drafting by fellows and staff in randomized sessions. We assessed EMR use as a fraction of work activity and according to technique, subspecialty, inpatient status, and radiologist experience. We observed 372 CT and MRI interpretations by 33 radiologists. For CT, radiologists used the EMR in 34% of abdominal, 57% of neuroradiologic, and 38% of musculoskeletal interpretations. For MRI, EMR was used in 73% of abdominal, 56% of neuroradiologic, and 33% of musculoskeletal interpretations. For CT, EMR usage comprised 18%, 14%, and 18% of diagnostic effort (image analysis plus EMR use) for abdominal, neuroradiologic, and musculoskeletal interpretations, respectively; for MRI, EMR usage comprised 21%, 16%, and 15% of diagnostic effort for abdominal, neuroradiologic, and musculoskeletal interpretations, respectively. Frequency of EMR use was significantly greater for neuroradiology CT and abdominal MRI (p < 0.05, Fisher's test). EMR usage was not consistently related to inpatient status for CT or radiologist experience. For CT and MRI interpretation, EMR usage is frequent and comprises a significant fraction of diagnostic effort.
-
Watemberg, Nathan; Tziperman, Barak; Dabby, Ron; Hasan, Mariana; Zehavi, Liora; Lerman-Sagie, Tally
2005-05-01
To report on the usefulness of adding video recording to routine EEG studies of infants and children with frequent paroxysmal events. We analyzed the efficacy of this diagnostic means during a 4-year period. The decision whether to add video recording was made by the pediatric EEG interpreter at the time of the study. Studies were planned to last between 20 and 30 min, and, if needed, were extended by the EEG interpreter. For most studies, video recording was added from the beginning of EEG recording. In a minority of cases, the addition of video was implemented during the first part of the EEG test, as clinical events became obvious. In these cases, a new study (file) was begun. The success rate was analyzed according to the indications for the EEG study: paroxysmal eye movements, tremor, suspected seizures, myoclonus, staring episodes, suspected stereotypias and tics, absence epilepsy follow-up, cyanotic episodes, and suspected psychogenic nonepileptic events. Video recording was added to 137 of 666 routine studies. Mean patient age was 4.8 years. The nature of the event was determined in 61 (45%) of the EEG studies. Twenty-eight percent were hospitalized patients. The average study duration was 26 min. This diagnostic means was particularly useful for paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and psychogenic nonepileptic events. About 46% of 116 patients for whom cognitive data were available were mentally retarded. EEG with added video recording was successfully performed in all 116 cases and provided useful information in 29 (55%) of these 53 patients. Adding video recording to routine EEG was helpful in 45% of cases referred for frequent paroxysmal events. This technique proved useful for hospitalized children as well as for outpatients. Moreover, it was successfully applied in cognitively impaired patients. Infants and children with paroxysmal eye movements, staring spells, myoclonic jerks, stereotypias, and pseudoseizures especially benefited from this diagnostic means. Because of its low cost and the little discomfort imposed on the patient and his or her family, this technique should be considered as a first diagnostic step in children with frequent paroxysmal events.
-
Fernández-Bussy, Sebastián; Labarca, Gonzalo; Canals, Sofia; Caviedes, Iván; Folch, Erik; Majid, Adnan
2015-01-01
OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive diagnostic test with a high diagnostic yield for suspicious central pulmonary lesions and for mediastinal lymph node staging. The main objective of this study was to describe the diagnostic yield of EBUS-TBNA for mediastinal lymph node staging in patients with suspected lung cancer. METHODS: Prospective study of patients undergoing EBUS-TBNA for diagnosis. Patients ≥ 18 years of age were recruited between July of 2010 and August of 2013. We recorded demographic variables, radiological characteristics provided by axial CT of the chest, location of the lesion in the mediastinum as per the International Association for the Study of Lung Cancer classification, and definitive diagnostic result (EBUS with a diagnostic biopsy or a definitive diagnostic method). RESULTS: Our analysis included 354 biopsies, from 145 patients. Of those 145 patients, 54.48% were male. The mean age was 63.75 years. The mean lymph node size was 15.03 mm, and 90 lymph nodes were smaller than 10.0 mm. The EBUS-TBNA method showed a sensitivity of 91.17%, a specificity of 100.0%, and a negative predictive value of 92.9%. The most common histological diagnosis was adenocarcinoma. CONCLUSIONS: EBUS-TBNA is a diagnostic tool that yields satisfactory results in the staging of neoplastic mediastinal lesions. PMID:26176519
-
Demographic and Practice Characteristics of Pathologists Who Enjoy Breast Tissue Interpretation
Oster, Natalia V.; Geller, Berta; Carney, Patricia A.; Reisch, Lisa M.; Onega, Tracy; Weaver, Donald L.; Frederick, Paul; Elmore, Joann G.
2015-01-01
Summary Physician attributes, job satisfaction and confidence in clinical skills are associated with enhanced performance and better patient outcomes. We surveyed 252 pathologists to evaluate associations between enjoyment of breast pathology, demographic/clinical characteristics and diagnostic performance. Diagnostic performance was determined by agreement with patient cases previously reviewed by a panel of experienced pathologists. Eighty-three percent of study participants reported enjoying breast pathology. Pathologists who enjoy breast interpretation were more likely to review ≥10 cases/week (p=0.003), report breast interpretation expertise (p=0.013), and high levels of confidence interpreting breast pathology (p<0.001). These pathologists were less likely to report that the field was challenging (p<0.001) and that breast cases make them more nervous than other types of pathology (p<0.001). Enjoyment was not associated with diagnostic performance. Millions of women undergo breast biopsy annually, thus it is reassuring that although nearly a fifth of practicing pathologists who interpret breast tissue report not enjoying the field, precision is not impacted. PMID:25554017
-
Yavarna, Tarunashree; Al-Dewik, Nader; Al-Mureikhi, Mariam; Ali, Rehab; Al-Mesaifri, Fatma; Mahmoud, Laila; Shahbeck, Noora; Lakhani, Shenela; AlMulla, Mariam; Nawaz, Zafar; Vitazka, Patrik; Alkuraya, Fowzan S; Ben-Omran, Tawfeg
2015-09-01
Clinical exome sequencing (CES) has become an increasingly popular diagnostic tool in patients with heterogeneous genetic disorders, especially in those with neurocognitive phenotypes. Utility of CES in consanguineous populations has not yet been determined on a large scale. A clinical cohort of 149 probands from Qatar with suspected Mendelian, mainly neurocognitive phenotypes, underwent CES from July 2012 to June 2014. Intellectual disability and global developmental delay were the most common clinical presentations but our cohort displayed other phenotypes, such as epilepsy, dysmorphism, microcephaly and other structural brain anomalies and autism. A pathogenic or likely pathogenic mutation, including pathogenic CNVs, was identified in 89 probands for a diagnostic yield of 60%. Consanguinity and positive family history predicted a higher diagnostic yield. In 5% (7/149) of cases, CES implicated novel candidate disease genes (MANF, GJA9, GLG1, COL15A1, SLC35F5, MAGE4, NEUROG1). CES uncovered two coexisting genetic disorders in 4% (6/149) and actionable incidental findings in 2% (3/149) of cases. Average time to diagnosis was reduced from 27 to 5 months. CES, which already has the highest diagnostic yield among all available diagnostic tools in the setting of Mendelian disorders, appears to be particularly helpful diagnostically in the highly consanguineous Middle Eastern population.
-
2013-01-01
Background Accurate prediction of Helicobacter pylori infection status on endoscopic images can contribute to early detection of gastric cancer, especially in Asia. We identified the diagnostic yield of endoscopy for H. pylori infection at various endoscopist career levels and the effect of two years of training on diagnostic yield. Methods A total of 77 consecutive patients who underwent endoscopy were analyzed. H. pylori infection status was determined by histology, serology, and the urea breast test and categorized as H. pylori-uninfected, -infected, or -eradicated. Distinctive endoscopic findings were judged by six physicians at different career levels: beginner (<500 endoscopies), intermediate (1500–5000), and advanced (>5000). Diagnostic yield and inter- and intra-observer agreement on H. pylori infection status were evaluated. Values were compared between the two beginners after two years of training. The kappa (K) statistic was used to calculate agreement. Results For all physicians, the diagnostic yield was 88.9% for H. pylori-uninfected, 62.1% for H. pylori-infected, and 55.8% for H. pylori-eradicated. Intra-observer agreement for H. pylori infection status was good (K > 0.6) for all physicians, while inter-observer agreement was lower (K = 0.46) for beginners than for intermediate and advanced (K > 0.6). For all physicians, good inter-observer agreement in endoscopic findings was seen for atrophic change (K = 0.69), regular arrangement of collecting venules (K = 0.63), and hemorrhage (K = 0.62). For beginners, the diagnostic yield of H. pylori-infected/eradicated status and inter-observer agreement of endoscopic findings were improved after two years of training. Conclusions The diagnostic yield of endoscopic diagnosis was high for H. pylori-uninfected cases, but was low for H. pylori-eradicated cases. In beginners, daily training on endoscopic findings improved the low diagnostic yield. PMID:23947684
-
Correcting the MoCA for education: effect on sensitivity.
Gagnon, Genevieve; Hansen, Kevin T; Woolmore-Goodwin, Sarah; Gutmanis, Iris; Wells, Jennie; Borrie, Michael; Fogarty, Jennifer
2013-09-01
The goal of this study was to quantify the impact of the suggested education correction on the sensitivity and specificity of the Montreal Cognitive Assessment (MoCA). Twenty-five outpatients with dementia and 39 with amnestic mild cognitive impairment (aMCI) underwent a diagnostic evaluation, which included the MoCA. Thirty-seven healthy controls also completed the MoCA and psychiatric, medical, neurological, functional, and cognitive difficulties were ruled out. For the total MoCA score, unadjusted for education, a cut-off score of 26 yielded the best balance between sensitivity and specificity (80% and 89% respectively) in identifying cognitive impairment (people with either dementia or aMCI, versus controls). When applying the education correction, sensitivity decreased from 80% to 69% for a small specificity increase (89% to 92%). The cut-off score yielding the best balance between sensitivity and specificity for the education adjusted MoCA score fell to 25 (61% and 97%, respectively). Adjusting the MoCA total score for education had a detrimental effect on sensitivity with only a slight increase in specificity. Clinically, this loss in sensitivity can lead to an increased number of false negatives, as education level does not always correlate to premorbid intellectual function. Clinical judgment about premorbid status should guide interpretation. However, as this effect may be cohort specific, age and education corrected norms and cut-offs should be developed to help guide MoCA interpretation.
-
Mason, Jay W; Hancock, E William; Gettes, Leonard S; Bailey, James J; Childers, Rory; Deal, Barbara J; Josephson, Mark; Kligfield, Paul; Kors, Jan A; Macfarlane, Peter; Pahlm, Olle; Mirvis, David M; Okin, Peter; Rautaharju, Pentti; Surawicz, Borys; van Herpen, Gerard; Wagner, Galen S; Wellens, Hein
2007-03-13
This statement provides a concise list of diagnostic terms for ECG interpretation that can be shared by students, teachers, and readers of electrocardiography. This effort was motivated by the existence of multiple automated diagnostic code sets containing imprecise and overlapping terms. An intended outcome of this statement list is greater uniformity of ECG diagnosis and a resultant improvement in patient care. The lexicon includes primary diagnostic statements, secondary diagnostic statements, modifiers, and statements for the comparison of ECGs. This diagnostic lexicon should be reviewed and updated periodically.
-
Mason, Jay W; Hancock, E William; Gettes, Leonard S; Bailey, James J; Childers, Rory; Deal, Barbara J; Josephson, Mark; Kligfield, Paul; Kors, Jan A; Macfarlane, Peter; Pahlm, Olle; Mirvis, David M; Okin, Peter; Rautaharju, Pentti; Surawicz, Borys; van Herpen, Gerard; Wagner, Galen S; Wellens, Hein
2007-03-13
This statement provides a concise list of diagnostic terms for ECG interpretation that can be shared by students, teachers, and readers of electrocardiography. This effort was motivated by the existence of multiple automated diagnostic code sets containing imprecise and overlapping terms. An intended outcome of this statement list is greater uniformity of ECG diagnosis and a resultant improvement in patient care. The lexicon includes primary diagnostic statements, secondary diagnostic statements, modifiers, and statements for the comparison of ECGs. This diagnostic lexicon should be reviewed and updated periodically.
-
Battaglia, A; Bianchini, E; Carey, J C
1999-01-01
The Consensus Conference of the American College of Medical Genetics has established guidelines regarding the evaluation of patients with mental retardation (MR) [Curry et al., Am. J. Med. Genet. 72:468-477, 1997]. They emphasized the high diagnostic utility of cytogenetic studies and of neuroimaging in certain clinical settings. However, data on the diagnostic yield of these studies in well-characterized populations of individuals with MR are scant. Majnemer and Shevell [J. Pediatr. 127:193-199, 1995] attained a diagnostic yield of 63%. However, this study included only 60 patients and the classification included pathogenetic and causal groups. The Stella Maris Institute has evaluated systematically patients with developmental delay (DD)/MR and performed various laboratory studies and neuroimaging in almost all patients. We report a retrospective analysis of the diagnostic yield of 120 consecutive patients observed at our Institute during the first 6 months of 1996. There were 77 males and 43 females; 47 were mildly delayed (IQ 70-50), 31 were moderately delayed (IQ 50-35), and 42 were severely delayed (IQ 35-20). Diagnostic studies (history, physical examination, standard cytogenetics, fragile X testing, molecular studies, electroencephalography, electromyography, nerve conduction studies, neuroimaging, and metabolic screening tests) yielded a causal diagnosis in 50 (41.6%) and a pathogenetic diagnosis in 47 (39.2%) of the 120 patients. Causal categories included chromosomal abnormalities (14), Fra(X) syndromes (4), known MCA/MR syndromes (19), fetal environmental syndromes (1), neurometabolic (3) disorders, neurocutaneous (3) disorders, hypoxic-ischemic encephalopathy (3), other encephalopathies (1), and congenital bilateral perisylvian syndrome (2). Pathogenetic categories included idiopathic MCA/MR syndromes (35), epileptic syndromes (10), and isolated lissencephaly sequence (2). Diagnostic yield did not differ across categories and degree of DD. Our results, while confirming the diagnostic utility of cytogenetic/molecular genetic, and neuroimaging studies, suggest the usefulness of accurate electroencephalogram recordings, and stress the importance of a thorough physical examination. Referral to a university child neurology and psychiatry service, where a comprehensive assessment with a selected battery of investigations is possible, yields etiologic findings in a high percentage of DD/MR patients, with important implications for management, prognosis and recurrence risk estimate.
-
Effectiveness of Toyota process redesign in reducing thyroid gland fine-needle aspiration error.
Raab, Stephen S; Grzybicki, Dana Marie; Sudilovsky, Daniel; Balassanian, Ronald; Janosky, Janine E; Vrbin, Colleen M
2006-10-01
Our objective was to determine whether the Toyota Production System process redesign resulted in diagnostic error reduction for patients who underwent cytologic evaluation of thyroid nodules. In this longitudinal, nonconcurrent cohort study, we compared the diagnostic error frequency of a thyroid aspiration service before and after implementation of error reduction initiatives consisting of adoption of a standardized diagnostic terminology scheme and an immediate interpretation service. A total of 2,424 patients underwent aspiration. Following terminology standardization, the false-negative rate decreased from 41.8% to 19.1% (P = .006), the specimen nondiagnostic rate increased from 5.8% to 19.8% (P < .001), and the sensitivity increased from 70.2% to 90.6% (P < .001). Cases with an immediate interpretation had a lower noninterpretable specimen rate than those without immediate interpretation (P < .001). Toyota process change led to significantly fewer diagnostic errors for patients who underwent thyroid fine-needle aspiration.
-
Benefit-risk Evaluation for Diagnostics: A Framework (BED-FRAME).
Evans, Scott R; Pennello, Gene; Pantoja-Galicia, Norberto; Jiang, Hongyu; Hujer, Andrea M; Hujer, Kristine M; Manca, Claudia; Hill, Carol; Jacobs, Michael R; Chen, Liang; Patel, Robin; Kreiswirth, Barry N; Bonomo, Robert A
2016-09-15
The medical community needs systematic and pragmatic approaches for evaluating the benefit-risk trade-offs of diagnostics that assist in medical decision making. Benefit-Risk Evaluation of Diagnostics: A Framework (BED-FRAME) is a strategy for pragmatic evaluation of diagnostics designed to supplement traditional approaches. BED-FRAME evaluates diagnostic yield and addresses 2 key issues: (1) that diagnostic yield depends on prevalence, and (2) that different diagnostic errors carry different clinical consequences. As such, evaluating and comparing diagnostics depends on prevalence and the relative importance of potential errors. BED-FRAME provides a tool for communicating the expected clinical impact of diagnostic application and the expected trade-offs of diagnostic alternatives. BED-FRAME is a useful fundamental supplement to the standard analysis of diagnostic studies that will aid in clinical decision making. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.
-
Francisco-Pascual, Jaume; Santos-Ortega, Alba; Roca-Luque, Ivo; Rivas-Gándara, Nuria; Pérez-Rodón, Jordi; Milà-Pascual, Laia; García-Dorado, David; Moya-Mitjans, Àngel
2018-05-24
To assess the diagnostic yield and cost-effectiveness of a diagnostic protocol based on the systematic use of latest-generation external loop recorders (ELRs) compared with the classic diagnostic strategy for patients with recurrent unexplained palpitations. Two cohorts of consecutive patients referred for diagnosis of unexplained palpitations to the outpatient clinic of the arrhythmia unit were compared: a prospective cohort after the implementation of a new diagnostic protocol based on the systematic use of ELRs, and another, retrospective, cohort before the implementation of the protocol. The cost of diagnosis was calculated based on the number of complementary examinations, visits to outpatient clinics, or emergency department visits required to reach a diagnosis, and its costs according the prices published for the local health system. One hundred and forty-nine patients were included (91 in the ELR group, 58 in the control group). The diagnostic yield was higher in the ELR group (79 [86.8%] definitive diagnoses in the ELR group vs 12 [20.7%] in the control group, P < .001). The cost per diagnosis was €375.13 in the ELR group and €5184.75 in the control group (P < .001). The cost-effectiveness study revealed that the systematic use of ELR resulted in a cost reduction of €11.30 for each percentage point of increase in diagnosis yield. In patients with recurrent unexplained palpitations, evaluation by means of a study protocol that considers the systematic use of a latest-generation ELR increases diagnostic yield while reducing the cost per diagnosis. Copyright © 2018 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
-
Snyder, C R; Larsen, D L; Bloom, L J
1976-04-01
There was no difference in the acceptance of a general personality interpretation supposedly based on psychological, graphological, or astrological assessment procedures. Ss told that their general personality interpretation was based on one of the three assessment procedures, however, accepted the interpretation to a greater degree than did Ss told the interpretation was "generally true of people." S faith in all assessment procedures and perceived diagnostician skill increased significantly from before to after receipt of the diagnostic feedback. Ss elicited a halo response after they had received the interpretation, such that they generated a highly consistent positive (or negative) view of the assessment procedures and diagnostician skills. Implications of results from this acceptance paradigm were discussed for diagnosticians and therapists.
-
Tuuli, Methodius G; Odibo, Anthony O
2011-08-01
The objective of this article is to discuss the rationale for common statistical tests used for the analysis and interpretation of prenatal diagnostic imaging studies. Examples from the literature are used to illustrate descriptive and inferential statistics. The uses and limitations of linear and logistic regression analyses are discussed in detail.
-
Anti-retroviral therapy-induced status epilepticus in "pseudo-HIV serodeconversion".
Etgen, Thorleif; Eberl, Bernhard; Freudenberger, Thomas
2010-01-01
Diligence in the interpretation of results is essential as information gained from the psychiatric patient's history might often be restricted. Nonobservance of established guidelines may lead to a wrong diagnosis, induce a false therapy and result in life-threatening situations. Communication errors between hospitals and doctors and uncritical acceptance of prior diagnoses add substantially to this problem. We present a patient with alcohol-related dementia who received anti-retroviral therapy that promoted a non-convulsive status epilepticus. HIV serodeconversion was considered after our laboratory result yielded a HIV-negative status. Critical review of previous diagnostic investigations revealed several errors in the diagnosis of HIV infection leading to a "pseudo-serodeconversion." Finally, anti-retroviral therapy could be discontinued. Copyright © 2010 Elsevier Inc. All rights reserved.
-
NASA Technical Reports Server (NTRS)
Wagner, Jeffrey; Hapke, Bruce; Wells, Eddie
1987-01-01
The reflectance spectra of powdered samples of selected minerals, meteorites, lunar materials and frosts are presented as an aid in the interpretation of present and future remote sensing data of solar system objects. Spectra obtained in separate wavelength regions have been combined and normalized, yielding coverage from 92 to 1800 nm. Spectral features include reflectance maxima in the far UV region produced by valence-conduction interband transitions, and reflectance minima in the near UV, visible and near IR regions, produced by charge transfer and crystal field transitions. Specific maxima and minima are diagnostic of mineral type and composition; additionally, the minerals present in mixtures such as meteorites and lunar samples can be determined.
-
Ellingford, Jamie M; Barton, Stephanie; Bhaskar, Sanjeev; Williams, Simon G; Sergouniotis, Panagiotis I; O'Sullivan, James; Lamb, Janine A; Perveen, Rahat; Hall, Georgina; Newman, William G; Bishop, Paul N; Roberts, Stephen A; Leach, Rick; Tearle, Rick; Bayliss, Stuart; Ramsden, Simon C; Nemeth, Andrea H; Black, Graeme C M
2016-05-01
To compare the efficacy of whole genome sequencing (WGS) with targeted next-generation sequencing (NGS) in the diagnosis of inherited retinal disease (IRD). Case series. A total of 562 patients diagnosed with IRD. We performed a direct comparative analysis of current molecular diagnostics with WGS. We retrospectively reviewed the findings from a diagnostic NGS DNA test for 562 patients with IRD. A subset of 46 of 562 patients (encompassing potential clinical outcomes of diagnostic analysis) also underwent WGS, and we compared mutation detection rates and molecular diagnostic yields. In addition, we compared the sensitivity and specificity of the 2 techniques to identify known single nucleotide variants (SNVs) using 6 control samples with publically available genotype data. Diagnostic yield of genomic testing. Across known disease-causing genes, targeted NGS and WGS achieved similar levels of sensitivity and specificity for SNV detection. However, WGS also identified 14 clinically relevant genetic variants through WGS that had not been identified by NGS diagnostic testing for the 46 individuals with IRD. These variants included large deletions and variants in noncoding regions of the genome. Identification of these variants confirmed a molecular diagnosis of IRD for 11 of the 33 individuals referred for WGS who had not obtained a molecular diagnosis through targeted NGS testing. Weighted estimates, accounting for population structure, suggest that WGS methods could result in an overall 29% (95% confidence interval, 15-45) uplift in diagnostic yield. We show that WGS methods can detect disease-causing genetic variants missed by current NGS diagnostic methodologies for IRD and thereby demonstrate the clinical utility and additional value of WGS. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
-
Wildgruber, Moritz; Wrede, Christian E; Zorger, Niels; Müller-Wille, René; Hamer, Okka W; Zeman, Florian; Stroszczynski, Christian; Heiss, Peter
2017-03-01
The diagnostic yield of computed tomography angiography (CTA) compared to digital subtraction angiography (DSA) for major obscure gastrointestinal bleeding (OGIB) is not known. Aim of the study was to prospectively evaluate the diagnostic yield of CTA versus DSA for the diagnosis of major OGIB. The institutional review board approved the study and informed consent was obtained from each patient. Patients with major OGIB were prospectively enrolled to undergo both CTA and DSA. Two blinded radiologists each reviewed the CTA and DSA images retrospectively and independently. Contrast material extravasation into the gastrointestinal lumen was considered diagnostic for active bleeding. Primary end point of the study was the diagnostic yield, defined as the frequency a technique identified an active bleeding or a potential bleeding lesion. The diagnostic yield of CTA and DSA were compared by McNemar's test. 24 consecutive patients (11 men; median age 64 years) were included. CTA and DSA identified an active bleeding or a potential bleeding lesion in 92% (22 of 24 patients; 95% CI 72%-99%) and 29% (7 of 24 patients; 95% CI 12%-49%) of patients, respectively (p<0.001). CTA and DSA identified an active bleeding in 42% (10 of 24; 95% CI 22%-63%) and 21% (5 of 24; 95% CI 7%-42%) of patients, respectively (p=0.06). Due to the lower invasiveness and higher diagnostic yield CTA should be favored over DSA for the diagnosis of major OGIB. Copyright © 2016. Published by Elsevier B.V.
-
Peralta, Victor; Cuesta, Manuel J
2005-11-15
The objective was to ascertain the underlying factor structure of alternative definitions of schizophrenia, and to examine the distribution of schizophrenia-related variables against the resulting factor solution. Twenty-three diagnostic schemes of schizophrenia were applied to 660 patients presenting with psychotic symptoms regardless of the specific diagnosis of psychotic disorder. Factor analysis of the 23 diagnostic schemes yielded three interpretable factors explaining 58% of the variance, the first factor (general schizophrenia factor) accounting for most of the variance (36%). On the basis of the general schizophrenia factor score, the sample was divided in quintile groups representing 5 levels of schizophrenia definition (absent, doubtful, very broad, broad and narrow) and the distribution of a number of schizophrenia-related variables was examined across the groups. This grouping procedure was used for examining the comparative validity of alternative levels of categorically defined schizophrenia and an ordinal (i.e. dimensional) definition. Overall, schizophrenia-related variables displayed a dose-response relationship with level of schizophrenia definition. Logistic regression analyses revealed that the dimensional definition explained more variance in the schizophrenia-related variables than the alternative levels for defining schizophrenia categorically. These results are consistent with a unitary and dimensional construct of schizophrenia with no clear "points of rarity" at its boundaries, thus supporting the continuum hypothesis of the psychotic illness.
-
Late-night salivary cortisol measurement in the diagnosis of Cushing's syndrome.
Carroll, Ty; Raff, Hershel; Findling, James W
2008-06-01
Making a definite diagnosis of Cushing's syndrome is a challenging problem. Unsuspected Cushing's syndrome occurs in 2-3% of patients with poorly controlled diabetes, 0.5-1% with hypertension, 6-9% with incidental adrenal masses, and 11% with unexplained osteoporosis and vertebral fractures. The increasing recognition of this syndrome highlights the need for a simple, sensitive, and specific diagnostic test. Patients with Cushing's syndrome consistently do not reach a normal nadir of cortisol secretion at night. The measurement of late-night salivary cortisol levels might, therefore, provide a new diagnostic approach for this disorder. Salivary cortisol concentrations reflect those of active free cortisol in plasma and saliva samples can easily be obtained in a nonstressful environment (e.g. at home). Late-night salivary cortisol measurement yields excellent overall diagnostic accuracy for Cushing's syndrome, with a sensitivity of 92-100% and a specificity of 93-100%. Several factors can, however, make interpretation of results difficult; these factors include disturbed sleep-wake cycles, contamination of samples (particularly by topical corticosteroids), and illnesses known to cause physiologic activation of the pituitary-adrenal axis. In this Review, we discuss the methods and value of measuring salivary cortisol for the diagnosis of Cushing's syndrome, and put forward some recommendations to maximize accuracy of results.
-
Goyal, Abhishek; Gupta, Dheeraj; Agarwal, Ritesh; Bal, Amanjit; Nijhawan, Raje; Aggarwal, Ashutosh N
2014-07-01
The exact position of routine bronchoscopic sampling techniques in diagnostic workup of sarcoidosis is often debated. Herein, we ascertain the role of transbronchial needle aspiration (TBNA), endobronchial ultrasound-guided TBNA (EBUS-TBNA), transbronchial lung biopsy (TBLB), and endobronchial biopsy (EBB) in diagnosis of sarcoidosis. Consecutive patients with suspected sarcoidosis who underwent fiberoptic bronchoscopy were studied. TBLB, EBB, TBNA, or EBUS-TBNA was performed as indicated in a standardized manner. A diagnosis of sarcoidosis was established based on the finding of non-necrotizing granulomas or on clinical grounds at 6-month follow-up. Individual and cumulative yield of various procedures and their correlation with clinicoradiologic parameters was analyzed. Of the 164 patients studied, 151 were finally diagnosed as sarcoidosis. Granulomas were demonstrated in 127 (84.2%) patients. Diagnostic yield of TBLB, EBB, TBNA, and EBUS-TBNA was 68.7%, 49.6%, 22.43%, and 57.1%, respectively. Cumulative yields of various procedures were: EBB+TBLB 81.4%; TBLB+TBNA 73.7%; TBNA+EBB 62.9%; TBLB+EBB+TBNA 86.9%; and TBLB+EBB+EBUS-TBNA 86.4%. In those with visible mucosal abnormalities, TBLB+EBB conferred the highest diagnostic yield (92.8%). Clinical findings or radiologic stage had no impact on diagnostic yield. TBLB is an important tool in bronchoscopic diagnosis of sarcoidosis. If endobronchial abnormalities are seen during bronchoscopy, TBLB with EBB gives the best results otherwise TBLB combined with conventional TBNA and EBB or EBUS-TBNA are required to maximize the diagnostic yield.
-
The Composition of Normative Groups and Diagnostic Decision Making: Shooting Ourselves in the Foot
ERIC Educational Resources Information Center
Pena, Elizabeth D.; Spaulding, Tammie J.; Plante, Elena
2006-01-01
Purpose: The normative group of a norm-referenced test is intended to provide a basis for interpreting test scores. However, the composition of the normative group may facilitate or impede different types of diagnostic interpretations. This article considers who should be included in a normative sample and how this decision must be made relative…
-
Zhou, Jian-hua; Shan, Hong-bo; Ou, Wei; Mo, Yun-xian; Xiang, Jin; Wang, Yu; Wang, Si-yu
2018-01-01
Based on the option that ultrasound-guided core needle biopsy (US-CNB) of the enhanced portion of anterior mediastinal masses (AMMs) identified by contrast-enhanced ultrasound (CEUS) would harvest viable tissue and benefit the histological diagnoses, a retrospective study was performed to elucidate the correlation between the prebiopsy CEUS and diagnostic yield of AMMs and found that CEUS potentially improved the diagnostic yield of AMMs compared with conventional US with a significant increase in the cellularity of samples. Furthermore, the marginal blood flow signals and absence of necrosis can predict the diagnostic yield of AMM. It was concluded that US-CNB of the viable part of AMMs, as verified by CEUS, was able to harvest sufficient tissue with more cellularity that could be used for ancillary studies and improve the diagnostic yield. And CEUS was recommended to those patients with AMMs undergoing repeated US-CNB, with the absence of marginal blood signals or presence of necrosis. PMID:29581992
-
Akulian, Jason; Lechtzin, Noah; Yasin, Faiza; Kamdar, Biren; Ernst, Armin; Ost, David E.; Ray, Cynthia; Greenhill, Sarah R.; Jimenez, Carlos A.; Filner, Joshua; Feller-Kopman, David
2013-01-01
Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure originally performed using a 22-gauge (22G) needle. A recently introduced 21-gauge (21G) needle may improve the diagnostic yield and sample adequacy of EBUS-TBNA, but prior smaller studies have shown conflicting results. To our knowledge, this is the largest study undertaken to date to determine whether the 21G needle adds diagnostic benefit. Methods: We retrospectively evaluated the results of 1,299 patients from the American College of Chest Physicians Quality Improvement Registry, Education, and Evaluation (AQuIRE) Diagnostic Registry who underwent EBUS-TBNA between February 2009 and September 2010 at six centers throughout the United States. Data collection included patient demographics, sample adequacy, and diagnostic yield. Analysis consisted of univariate and multivariate hierarchical logistic regression comparing diagnostic yield and sample adequacy of EBUS-TBNA specimens by needle gauge. Results: A total of 1,235 patients met inclusion criteria. Sample adequacy was obtained in 94.9% of the 22G needle group and in 94.6% of the 21G needle group (P = .81). A diagnosis was made in 51.4% of the 22G and 51.3% of the 21G groups (P = .98). Multivariate hierarchical logistic regression showed no statistical difference in sample adequacy or diagnostic yield between the two groups. The presence of rapid onsite cytologic evaluation was associated with significantly fewer needle passes per procedure when using the 21G needle (P < .001). Conclusions: There is no difference in specimen adequacy or diagnostic yield between the 21G and 22G needle groups. EBUS-TBNA in conjunction with rapid onsite cytologic evaluation and a 21G needle is associated with fewer needle passes compared with a 22G needle. PMID:23632441
-
Monroe, Glen R; Frederix, Gerardus W; Savelberg, Sanne M C; de Vries, Tamar I; Duran, Karen J; van der Smagt, Jasper J; Terhal, Paulien A; van Hasselt, Peter M; Kroes, Hester Y; Verhoeven-Duif, Nanda M; Nijman, Isaäc J; Carbo, Ellen C; van Gassen, Koen L; Knoers, Nine V; Hövels, Anke M; van Haelst, Mieke M; Visser, Gepke; van Haaften, Gijs
2016-09-01
This study investigated whole-exome sequencing (WES) yield in a subset of intellectually disabled patients referred to our clinical diagnostic center and calculated the total costs of these patients' diagnostic trajectory in order to evaluate early WES implementation. We compared 17 patients' trio-WES yield with the retrospective costs of diagnostic procedures by comprehensively examining patient records and collecting resource use information for each patient, beginning with patient admittance and concluding with WES initiation. We calculated cost savings using scenario analyses to evaluate the costs replaced by WES when used as a first diagnostic tool. WES resulted in diagnostically useful outcomes in 29.4% of patients. The entire traditional diagnostic trajectory average cost was $16,409 per patient, substantially higher than the $3,972 trio-WES cost. WES resulted in average cost savings of $3,547 for genetic and metabolic investigations in diagnosed patients and $1,727 for genetic investigations in undiagnosed patients. The increased causal variant detection yield by WES and the relatively high costs of the entire traditional diagnostic trajectory suggest that early implementation of WES is a relevant and cost-efficient option in patient diagnostics. This information is crucial for centers considering implementation of WES and serves as input for future value-based research into diagnostics.Genet Med 18 9, 949-956.
-
Tammimies, Kristiina; Marshall, Christian R; Walker, Susan; Kaur, Gaganjot; Thiruvahindrapuram, Bhooma; Lionel, Anath C; Yuen, Ryan K C; Uddin, Mohammed; Roberts, Wendy; Weksberg, Rosanna; Woodbury-Smith, Marc; Zwaigenbaum, Lonnie; Anagnostou, Evdokia; Wang, Zhuozhi; Wei, John; Howe, Jennifer L; Gazzellone, Matthew J; Lau, Lynette; Sung, Wilson W L; Whitten, Kathy; Vardy, Cathy; Crosbie, Victoria; Tsang, Brian; D'Abate, Lia; Tong, Winnie W L; Luscombe, Sandra; Doyle, Tyna; Carter, Melissa T; Szatmari, Peter; Stuckless, Susan; Merico, Daniele; Stavropoulos, Dimitri J; Scherer, Stephen W; Fernandez, Bridget A
2015-09-01
The use of genome-wide tests to provide molecular diagnosis for individuals with autism spectrum disorder (ASD) requires more study. To perform chromosomal microarray analysis (CMA) and whole-exome sequencing (WES) in a heterogeneous group of children with ASD to determine the molecular diagnostic yield of these tests in a sample typical of a developmental pediatric clinic. The sample consisted of 258 consecutively ascertained unrelated children with ASD who underwent detailed assessments to define morphology scores based on the presence of major congenital abnormalities and minor physical anomalies. The children were recruited between 2008 and 2013 in Newfoundland and Labrador, Canada. The probands were stratified into 3 groups of increasing morphological severity: essential, equivocal, and complex (scores of 0-3, 4-5, and ≥6). All probands underwent CMA, with WES performed for 95 proband-parent trios. The overall molecular diagnostic yield for CMA and WES in a population-based ASD sample stratified in 3 phenotypic groups. Of 258 probands, 24 (9.3%, 95%CI, 6.1%-13.5%) received a molecular diagnosis from CMA and 8 of 95 (8.4%, 95%CI, 3.7%-15.9%) from WES. The yields were statistically different between the morphological groups. Among the children who underwent both CMA and WES testing, the estimated proportion with an identifiable genetic etiology was 15.8% (95%CI, 9.1%-24.7%; 15/95 children). This included 2 children who received molecular diagnoses from both tests. The combined yield was significantly higher in the complex group when compared with the essential group (pairwise comparison, P = .002). [table: see text]. Among a heterogeneous sample of children with ASD, the molecular diagnostic yields of CMA and WES were comparable, and the combined molecular diagnostic yield was higher in children with more complex morphological phenotypes in comparison with the children in the essential category. If replicated in additional populations, these findings may inform appropriate selection of molecular diagnostic testing for children affected by ASD.
-
Fan, Yanjie; Wu, Yanming; Wang, Lili; Wang, Yu; Gong, Zhuwen; Qiu, Wenjuan; Wang, Jingmin; Zhang, Huiwen; Ji, Xing; Ye, Jun; Han, Lianshu; Jin, Xingming; Shen, Yongnian; Li, Fei; Xiao, Bing; Liang, Lili; Zhang, Xia; Liu, Xiaomin; Gu, Xuefan; Yu, Yongguo
2018-05-24
Developmental delay (DD) and intellectual disability (ID) are frequently associated with a broad spectrum of additional phenotypes. Chromosomal microarray analysis (CMA) has been recommended as a first-tier test for DD/ID in general, whereas the diagnostic yield differs significantly among DD/ID patients with different comorbid conditions. To investigate the genotype-phenotype correlation, we examined the characteristics of identified pathogenic copy number variations (pCNVs) and compared the diagnostic yields among patient subgroups with different co-occurring conditions. This study is a retrospective review of CMA results generated from a mixed cohort of 710 Chinese patients with DD/ID. A total of 247 pCNVs were identified in 201 patients (28%). A large portion of these pCNVs were copy number losses, and the size of copy number losses was generally smaller than gains. The diagnostic yields were significantly higher in subgroups with co-occurring congenital heart defects (55%), facial dysmorphism (39%), microcephaly (34%) or hypotonia (35%), whereas co-occurring conditions of skeletal malformation (26%), brain malformation (24%) or epilepsy (24%) did not alter the yield. In addition, the diagnostic yield nominally correlated with ID severity. Varied yields exist in DD/ID patients with different phenotypic presentation. The presence of comorbid conditions can be among factors to consider when planning CMA.
-
Walters, Glenn D; Diamond, Pamela M; Magaletta, Philip R
2010-03-01
Three indicators derived from the Personality Assessment Inventory (PAI) Alcohol Problems scale (ALC)-tolerance/high consumption, loss of control, and negative social and psychological consequences-were subjected to taxometric analysis-mean above minus below a cut (MAMBAC), maximum covariance (MAXCOV), and latent mode factor analysis (L-Mode)-in 1,374 federal prison inmates (905 males, 469 females). Whereas the total sample yielded ambiguous results, the male subsample produced dimensional results, and the female subsample produced taxonic results. Interpreting these findings in light of previous taxometric research on alcohol abuse and dependence it is speculated that while alcohol use disorders may be taxonic in female offenders, they are probably both taxonic and dimensional in male offenders. Two models of male alcohol use disorder in males are considered, one in which the diagnostic features are categorical and the severity of symptomatology is dimensional, and one in which some diagnostic features (e.g., withdrawal) are taxonic and other features (e.g., social problems) are dimensional.
-
Bourque, Jamieson M.; Beller, George A.
2015-01-01
Exercise stress electrocardiography (ExECG) is underutilized as the initial test modality in patients with interpretable electrocardiograms able to exercise. Although, stress myocardial imaging techniques provide valuable diagnostic and prognostic information, variables derived from ExECG can yield substantial data for risk stratification, either supplementary to imaging variables, or without concurrent imaging. In addition to exercise-induced ischemic ST depression, such markers as ST segment elevation in lead AVR, abnormal heart rate recovery post-exercise, failure to achieve target heart rate, and poor exercise capacity improve risk stratification of ExECG. For example, patients achieving ≥10 METS on ExECG have a very low prevalence of inducible ischemia and an excellent prognosis. In contrast, cardiac imaging techniques add diagnostic and prognostic value in higher risk populations (e.g. poor functional capacity, diabetes, chronic kidney disease). Optimal test selection for symptomatic patients with suspected coronary artery disease requires a patient-centered approach factoring in the risk/benefit ratio and cost-effectiveness. PMID:26563861
-
Nasal potential difference measurements in diagnosis of cystic fibrosis: an international survey.
Naehrlich, Lutz; Ballmann, Manfred; Davies, Jane; Derichs, Nico; Gonska, Tanja; Hjelte, Lena; van Konigsbruggen-Rietschel, Silke; Leal, Teresinha; Melotti, Paola; Middleton, Peter; Tümmler, Burkhard; Vermeulen, Francois; Wilschanski, Michael
2014-01-01
The role of nasal potential difference (NPD) measurement as a diagnostic test for cystic fibrosis (CF) is a subject of global controversy because of the lack of validation studies, clear reference values, and standardized protocols for diagnostic NPD. To determine diagnostic NPD frequency, protocols, interpretation, and rater agreement, we surveyed the 18 NPD centres of the European Cystic Fibrosis Society Diagnostic Network Working Group. Fifteen centres reported performing 373 diagnostic NPDs in 2012. Most use the CFF-TDN-SOP (67%) and the chloride-free + isoproterenol response of the side with the largest response (47%) as diagnostic criteria and use centre-specific reference ranges. Rater agreement for five NPD tracings - in general - was good, but poor in tracings with different responses between the two nostrils. NPD is frequently used as a diagnostic and research tool for CF. Performance is highly standardized, centre-specific reference ranges are established, and rater agreement - in general - is good. Centre-independent diagnostic criteria and reference ranges must be defined by multicentre validation studies to improve standardized interpretation for diagnostic use. © 2013.
-
Artificial neural networks in mammography interpretation and diagnostic decision making.
Ayer, Turgay; Chen, Qiushi; Burnside, Elizabeth S
2013-01-01
Screening mammography is the most effective means for early detection of breast cancer. Although general rules for discriminating malignant and benign lesions exist, radiologists are unable to perfectly detect and classify all lesions as malignant and benign, for many reasons which include, but are not limited to, overlap of features that distinguish malignancy, difficulty in estimating disease risk, and variability in recommended management. When predictive variables are numerous and interact, ad hoc decision making strategies based on experience and memory may lead to systematic errors and variability in practice. The integration of computer models to help radiologists increase the accuracy of mammography examinations in diagnostic decision making has gained increasing attention in the last two decades. In this study, we provide an overview of one of the most commonly used models, artificial neural networks (ANNs), in mammography interpretation and diagnostic decision making and discuss important features in mammography interpretation. We conclude by discussing several common limitations of existing research on ANN-based detection and diagnostic models and provide possible future research directions.
-
Diagnostic yield and safety of closed needle pleural biopsy in exudative pleural effusion.
Rajawat, Govind Singh; Batra, Supreet; Takhar, Rajendra Prasad; Rathi, Lalit; Bhandari, Chand; Gupta, Manohar Lal
2017-01-01
Closed pleural biopsy was previously considered a procedure of choice in cases of undiagnosed pleural effusion with good efficacy. Currently, the closed pleural biopsy has been replaced by thoracoscopic biopsy but not easily available in resource-limited setups. The objective of this study was to analyze the diagnostic yield and safety of closed needle pleural biopsy in exudative pleural effusion and assessment of patients' characteristics with the yield of pleural biopsy. This was a cross-sectional study. This study was conducted at Institute of Respiratory Diseases, SMS Medical College, Jaipur, a tertiary care center of West India. A total of 250 cases of pleural effusion were evaluated with complete pleural fluid biochemical, microbiological, and cytological examination. Out of these 250 patients, 59 were excluded from the study as the diagnosis could be established on initial pleural fluid examination. The remaining (191) patients were considered for closed pleural biopsy with Abrams pleural biopsy needle. The main outcome measure was diagnostic yield in the form of confirming diagnosis. Out of the 191 patients with exudative lymphocytic pleural effusion, 123 (64.40%) were diagnosed on the first pleural biopsy. Among the remaining 68 patients, 22 patients had repeat pleural biopsy with a diagnostic yield of 59.9%. The overall pleural biopsy could establish the diagnosis in 136 (71.20%) patients with pleural effusion. The most common diagnosis on pleural biopsy was malignancy followed by tuberculosis. Closed pleural biopsy provides diagnostic yield nearly comparative to thoracoscopy in properly selected patients of pleural effusions. In view of good yield, low cost, easy availability, and very low complication rate, it should be used routinely in all cases of undiagnosed exudative lymphocytic pleural effusion. There was no comparison with a similar group undergoing thoracoscopic pleural biopsy.
-
Leighton, Jonathan A; Helper, Debra J; Gralnek, Ian M; Dotan, Iris; Fernandez-Urien, Ignacio; Lahat, Adi; Malik, Pramod; Mullin, Gerard E; Rosa, Bruno
2017-01-01
Crohn's disease (CD) is typically diagnosed with ileocolonoscopy (IC); however, when inflammation is localized solely in the small bowel, visualization of the entire small-bowel mucosa can be challenging. The aim of this study was to compare the diagnostic yield of a pan-enteric video capsule endoscope (small-bowel colon [SBC] capsule) versus IC in patients with active CD. This was a prospective, multicenter study. Patients with known active CD and proven bowel luminal patency underwent a standardized colon cleansing protocol followed by ingestion of the capsule. After passage of the capsule, IC was performed and recorded. Lesions indicative of active CD were assessed. One hundred fourteen subjects were screened; 66 subjects completed both endoscopic procedures. The per-subject diagnostic yield rate for active CD lesions was 83.3% for SBC and 69.7% for IC (yield difference, 13.6%; 95% confidence interval [CI], 2.6%-24.7%); 65% of subjects had active CD lesions identified by both modalities. Of the 12 subjects who were positive for active CD by SBC only, 5 subjects were found to have active CD lesions in the terminal ileum. Three subjects were positive for active CD by IC only. Three hundred fifty-five classifying bowel segments were analyzed; the per-segment diagnostic yield rate was 40.6% for SBC and 32.7% for IC (yield difference 7.9%; 95% CI, 3.3%-12.4%). This preliminary study shows that the diagnostic yields for SBC might be higher than IC; however, the magnitude of difference between the two is difficult to estimate. Further study is needed to confirm these findings. Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.
-
Electromagnetic navigation diagnostic bronchoscopy for small peripheral lung lesions.
Makris, D; Scherpereel, A; Leroy, S; Bouchindhomme, B; Faivre, J-B; Remy, J; Ramon, P; Marquette, C-H
2007-06-01
The present study prospectively evaluated the diagnostic yield and safety of electromagnetic navigation-guided bronchoscopy biopsy, for small peripheral lung lesions in patients where standard techniques were nondiagnostic. The study was conducted in a tertiary medical centre on 40 consecutive patients considered unsuitable for straightforward surgery or computed tomography (CT)-guided transthoracic needle aspiration biopsy, due to comorbidities. The lung lesion diameter was mean+/-sem 23.5+/-1.5 mm and the depth from the visceral-costal pleura was 14.9+/-2 mm. Navigation was facilitated by an electromagnetic tracking system which could detect a position sensor incorporated into a flexible catheter advanced through a bronchoscope. Information obtained during bronchoscopy was superimposed on previously acquired CT data. Divergence between CT data and data obtained during bronchoscopy was calculated by the system's software as a measure of navigational accuracy. All but one of the target lesions was reached and the overall diagnostic yield was 62.5% (25-40). Diagnostic yield was significantly affected by CT-to-body divergence; yield was 77.2% when estimated divergence was
-
Boal Carvalho, Pedro; Magalhães, Joana; Dias de Castro, Francisca; Gonçalves, Tiago Cúrdia; Rosa, Bruno; Moreira, Maria João; Cotter, José
2016-02-01
Small bowel capsule endoscopy represents the initial investigation for obscure gastrointestinal bleeding. Flexible spectral imaging colour enhancement (FICE) is a virtual chromoendoscopy technique designed to enhance mucosal lesions, available in different settings according to light wavelength-- FICE1, 2 and 3. To compare the diagnostic yield of FICE1 and white light during capsule endoscopy in patients with obscure gastrointestinal bleeding. Retrospective single-centre study including 60 consecutive patients referred for small bowel capsule endoscopy for obscure gastrointestinal bleeding. Endoscopies were independently reviewed in FICE1 and white light; findings were then reviewed by another researcher, establishing a gold standard. Diagnostic yield was defined as the presence of lesions with high bleeding potential (P2) angioectasias, ulcers or tumours. Diagnostic yield using FICE1 was significantly higher than white light (55% vs. 42%, p=0.021). A superior number of P2 lesions was detected with FICE1 (74 vs. 44, p=0.003), particularly angioectasias (54 vs. 26, p=0.002), but not ulcers or tumours. FICE1 was significantly superior to white light, resulting in a 13% improvement in diagnostic yield, and potentially bleeding lesions particularly angioectasias were more often observed. Our results support the use of FICE1 while reviewing small bowel capsule endoscopy for obscure gastrointestinal bleeding. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
-
NASA Technical Reports Server (NTRS)
Zimetbaum, P. J.; Kim, K. Y.; Josephson, M. E.; Goldberger, A. L.; Cohen, D. J.
1998-01-01
BACKGROUND: Continuous-loop event recorders are widely used for the evaluation of palpitations, but the optimal duration of monitoring is unknown. OBJECTIVE: To determine the yield, timing, and incremental cost-effectiveness of each week of event monitoring for palpitations. DESIGN: Prospective cohort study. PATIENTS: 105 consecutive outpatients referred for the placement of a continuous-loop event recorder for the evaluation of palpitations. MEASUREMENTS: Diagnostic yield, incremental cost, and cost-effectiveness for each week of monitoring. RESULTS: The diagnostic yield of continuous-loop event recorders was 1.04 diagnoses per patient in week 1, 0.15 diagnoses per patient in week 2, and 0.01 diagnoses per patient in week 3 and beyond. Over time, the cost-effectiveness ratio increased from $98 per new diagnosis in week 1 to $576 per new diagnosis in week 2 and $5832 per new diagnosis in week 3. CONCLUSIONS: In patients referred for evaluation of palpitations, the diagnostic yield of continuous-loop event recording decreases rapidly after 2 weeks of monitoring. A 2-week monitoring period is reasonably cost-effective for most patients and should be the standard period for continuous-loop event recording for the evaluation of palpitations.
-
NASA Astrophysics Data System (ADS)
Yang, Thomas; Shen, Yang; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh
2017-03-01
Silicon testing results are regularly collected for a particular lot of wafers to study yield loss from test result diagnostics. Product engineers will analyze the diagnostic results and perform a number of physical failure analyses to detect systematic defects which cause yield loss for these sets of wafers in order to feedback the information to process engineers for process improvements. Most of time, the systematic defects that are detected are major issues or just one of the causes for the overall yield loss. This paper will present a working flow for using design analysis techniques combined with diagnostic methods to systematically transform silicon testing information into physical layout information. A new set of the testing results are received from a new lot of wafers for the same product. We can then correlate all the diagnostic results from different periods of time to check which blocks or nets have been highlighted or stop occurring on the failure reports in order to monitor process changes which impact the yield. The design characteristic analysis flow is also implemented to find 1) the block connections on a design that have failed electrical test or 2) frequently used cells that been highlighted multiple times.
-
Konishi, Masaru; Lindh, Christina; Nilsson, Mats; Tanimoto, Keiji; Rohlin, Madeleine
2012-08-01
The aims of this study were to review the literature on intraoral digital radiography in endodontic treatment with focus on technical parameters and to propose recommendations for improving the quality of reports in future publications. Two electronic databases were searched. Titles and abstracts were selected according to preestablished criteria. Data were extracted using a model of image acquisition and interpretation. The literature search yielded 233 titles and abstracts; 61 reports were read in full text. Recent reports presented technical parameters more thoroughly than older reports. Most reported important parameters for the x-ray unit, but for image interpretation only about one-half of the publications cited resolution of the display system and fewer than one-half bit depth of the graphics card. The methodologic quality of future publications must be improved to permit replication of studies and comparison of results between studies in dental digital radiography. Our recommendations can improve the quality of studies on diagnostic accuracy. Copyright © 2012 Mosby, Inc. All rights reserved.
-
Diagnostic Yield of Computed Tomography Scan for Pediatric Hearing Loss: A Systematic Review
Chen, Jenny X.; Kachniarz, Bart; Shin, Jennifer J.
2015-01-01
Background Computed tomography (CT) has been used in the assessment of pediatric hearing loss, but concern regarding radiation risk and increased utilization of magnetic resonance imaging (MRI) have prompted us toward a more quantitative and sophisticated understanding of CT’s potential diagnostic yield. Objective To perform a systematic review to analyze the diagnostic yield of CT for pediatric hearing loss, including subgroup evaluation according to impairment severity and laterality, as well as the specific findings of enlarged vestibular aqueduct and narrow cochlear nerve canal. Data Sources PubMed, EMBASE, and the Cochrane Library were assessed from the date of their inception to December 2013. In addition, manual searches of bibliographies were performed and topic experts were contacted. Review Methods Data from studies describing the use of CT in the diagnostic evaluation of pediatric patients with hearing loss of unknown etiology were evaluated, according to a priori inclusion/exclusion criteria. Two independent evaluators corroborated the extracted data. Heterogeneity was evaluated according to the I2 statistic. Results In 50 criteria-meeting studies, the overall diagnostic yield of CT ranged from 7% to 74%, with the strongest and aggregate data demonstrating a point estimate of 30%. This estimate corresponded to a number needed to image of 4 (range, 2–15). The most commonly identified findings were enlarged vestibular aqueduct and cochlear anomalies. The largest studies showed a 4% to 7% yield for narrow cochlear nerve canal. Conclusion These data, along with similar analyses of radiation risk and risks/benefits of sedated MRI, may be used to help guide the choice of diagnostic imaging. PMID:25186339
-
Skin prick tests and allergy diagnosis.
Antunes, João; Borrego, Luís; Romeira, Ana; Pinto, Paula
2009-01-01
Skin testing remains an essential diagnostic tool in modern allergy practice. A significant variability has been reported regarding technical procedures, interpretation of results and documentation. This review has the aim of consolidating methodological recommendations through a critical analysis on past and recent data. This will allow a better understanding on skin prick test (SPT) history; technique; (contra-) indications; interpretation of results; diagnostic pitfalls; adverse reactions; and variability factors.
-
ROC analysis for diagnostic accuracy of fracture by using different monitors.
Liang, Zhigang; Li, Kuncheng; Yang, Xiaolin; Du, Xiangying; Liu, Jiabin; Zhao, Xin; Qi, Xiangdong
2006-09-01
The purpose of this study was to compare diagnostic accuracy by using two types of monitors. Four radiologists with 10 years experience twice interpreted the films of 77 fracture cases by using the ViewSonic P75f+ and BARCO MGD221 monitors, with a time interval of 3 weeks. Each time the radiologists used one type of monitor to interpret the images. The image browser used was the Unisight software provided by Atlastiger Company (Shanghai, China), and interpretation result was analyzed via the LABMRMC software. In studies of receiver operating characteristics to score the presence or absence of fracture, the results of images interpreted through monochromic monitors showed significant statistical difference compared to those interpreted using the color monitors. A significant difference was observed in the results obtained by using two kinds of monitors. Color monitors cannot serve as substitutes for monochromatic monitors in the process of interpreting computed radiography (CR) images with fractures.
-
Pulmonary Infiltrates in Immunosuppressed Patients: Analysis of a Diagnostic Protocol
Danés, Cristina; González-Martín, Julián; Pumarola, Tomàs; Rañó, Ana; Benito, Natividad; Torres, Antoni; Moreno, Asunción; Rovira, Montserrat; Puig de la Bellacasa, Jorge
2002-01-01
A diagnostic protocol was started to study the etiology of pulmonary infiltrates in immunosuppressed patients. The diagnostic yields of the different techniques were analyzed, with special emphasis on the importance of the sample quality and the role of rapid techniques in the diagnostic strategy. In total, 241 patients with newly developed pulmonary infiltrates within a period of 19 months were included. Noninvasive or invasive evaluation was performed according to the characteristics of the infiltrates. Diagnosis was achieved in 202 patients (84%); 173 patients (72%) had pneumonia, and specific etiologic agents were found in 114 (66%). Bronchoaspirate and bronchoalveolar lavage showed the highest yields, either on global analysis (23 of 35 specimens [66%] and 70 of 134 specimens [52%], respectively) or on analysis of each type of pneumonia. A tendency toward better results with optimal-quality samples was observed, and a statistically significant difference was found in sputum bacterial culture. Rapid diagnostic tests yielded results in 71 of 114 (62.2%) diagnoses of etiological pneumonia. PMID:12037077
-
Cairns, Andrew W; Bond, Raymond R; Finlay, Dewar D; Guldenring, Daniel; Badilini, Fabio; Libretti, Guido; Peace, Aaron J; Leslie, Stephen J
The 12-lead Electrocardiogram (ECG) has been used to detect cardiac abnormalities in the same format for more than 70years. However, due to the complex nature of 12-lead ECG interpretation, there is a significant cognitive workload required from the interpreter. This complexity in ECG interpretation often leads to errors in diagnosis and subsequent treatment. We have previously reported on the development of an ECG interpretation support system designed to augment the human interpretation process. This computerised decision support system has been named 'Interactive Progressive based Interpretation' (IPI). In this study, a decision support algorithm was built into the IPI system to suggest potential diagnoses based on the interpreter's annotations of the 12-lead ECG. We hypothesise semi-automatic interpretation using a digital assistant can be an optimal man-machine model for ECG interpretation. To improve interpretation accuracy and reduce missed co-abnormalities. The Differential Diagnoses Algorithm (DDA) was developed using web technologies where diagnostic ECG criteria are defined in an open storage format, Javascript Object Notation (JSON), which is queried using a rule-based reasoning algorithm to suggest diagnoses. To test our hypothesis, a counterbalanced trial was designed where subjects interpreted ECGs using the conventional approach and using the IPI+DDA approach. A total of 375 interpretations were collected. The IPI+DDA approach was shown to improve diagnostic accuracy by 8.7% (although not statistically significant, p-value=0.1852), the IPI+DDA suggested the correct interpretation more often than the human interpreter in 7/10 cases (varying statistical significance). Human interpretation accuracy increased to 70% when seven suggestions were generated. Although results were not found to be statistically significant, we found; 1) our decision support tool increased the number of correct interpretations, 2) the DDA algorithm suggested the correct interpretation more often than humans, and 3) as many as 7 computerised diagnostic suggestions augmented human decision making in ECG interpretation. Statistical significance may be achieved by expanding sample size. Copyright © 2017 Elsevier Inc. All rights reserved.
-
Zweben, S. J.; Terry, J. L.; Stotler, D. P.; ...
2017-04-27
Gas puff imaging (GPI) is a diagnostic of plasma turbulence which uses a puff of neutral gas at the plasma edge to increase the local visible light emission for improved space-time resolution of plasma fluctuations. This paper reviews gas puff imaging diagnostics of edge plasma turbulence in magnetic fusion research, with a focus on the instrumentation, diagnostic cross-checks, and interpretation issues. The gas puff imaging hardware, optics, and detectors are described for about 10 GPI systems implemented over the past similar to 15 years. Comparison of GPI results with other edge turbulence diagnostic results is described, and many common featuresmore » are observed. Here, several issues in the interpretation of GPI measurements are discussed, and potential improvements in hardware and modeling are suggested.« less
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zweben, S. J.; Terry, J. L.; Stotler, D. P.
Gas puff imaging (GPI) is a diagnostic of plasma turbulence which uses a puff of neutral gas at the plasma edge to increase the local visible light emission for improved space-time resolution of plasma fluctuations. This paper reviews gas puff imaging diagnostics of edge plasma turbulence in magnetic fusion research, with a focus on the instrumentation, diagnostic cross-checks, and interpretation issues. The gas puff imaging hardware, optics, and detectors are described for about 10 GPI systems implemented over the past similar to 15 years. Comparison of GPI results with other edge turbulence diagnostic results is described, and many common featuresmore » are observed. Here, several issues in the interpretation of GPI measurements are discussed, and potential improvements in hardware and modeling are suggested.« less
-
Understanding the properties of diagnostic tests - Part 2: Likelihood ratios.
Ranganathan, Priya; Aggarwal, Rakesh
2018-01-01
Diagnostic tests are used to identify subjects with and without disease. In a previous article in this series, we examined some attributes of diagnostic tests - sensitivity, specificity, and predictive values. In this second article, we look at likelihood ratios, which are useful for the interpretation of diagnostic test results in everyday clinical practice.
-
Adaptation of an articulated fetal skeleton model to three-dimensional fetal image data
NASA Astrophysics Data System (ADS)
Klinder, Tobias; Wendland, Hannes; Wachter-Stehle, Irina; Roundhill, David; Lorenz, Cristian
2015-03-01
The automatic interpretation of three-dimensional fetal images poses specific challenges compared to other three-dimensional diagnostic data, especially since the orientation of the fetus in the uterus and the position of the extremities is highly variable. In this paper, we present a comprehensive articulated model of the fetal skeleton and the adaptation of the articulation for pose estimation in three-dimensional fetal images. The model is composed out of rigid bodies where the articulations are represented as rigid body transformations. Given a set of target landmarks, the model constellation can be estimated by optimization of the pose parameters. Experiments are carried out on 3D fetal MRI data yielding an average error per case of 12.03+/-3.36 mm between target and estimated landmark positions.
-
NASA Astrophysics Data System (ADS)
Lar'kin, A.; Uryupina, D.; Ivanov, K.; Savel'ev, A.; Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M.; Spohr, K.; Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T.
2014-09-01
By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition.
-
Closed percutaneous pleural biopsy. A lost art in the new era.
Khadadah, Mousa E; Muqim, Abdulaziz T; Al-Mutairi, Abdulla D; Nahar, Ibrahim K; Sharma, Prem N; Behbehani, Nasser H; El-Maradni, Nabeel M
2009-06-01
To assess the association between size and number of biopsy specimens obtained by percutaneous closed pleural biopsy, with overall diagnostic yield in general, and histopathological evidence of tuberculosis pleurisy, in particular. One hundred and forty-three patients, with a high index of clinically having tuberculous pleurisy, were referred to the respiratory division of Mubarak Al-Kabeer Hospital in Kuwait during a 9-year period (January 1999 to December 2007). All subjects with exudative lymphocytic predominant effusion underwent percutaneous closed pleural biopsy, looking for tuberculous granulomas. The clinical diagnosis and pathological characteristics (number and size of biopsy samples) were analyzed. Overall diagnostic yield of percutaneous closed pleural biopsy in all cases was noticed to be 52%. The larger biopsy sample size of 3 mm and more, and the higher number of specimens (> or = 4) were significantly associated with an increased diagnostic yield for tuberculous pleurisy (p=0.007 and 0.047). Obtaining 4 or more biopsy samples, and larger specimens of 3mm and more for histopathological evaluation, through percutaneous pleural biopsy, results in a better diagnostic yield for tuberculous pleurisy.
-
NASA Technical Reports Server (NTRS)
Fronzek, Stefan; Pirttioja, Nina; Carter, Timothy R.; Bindi, Marco; Hoffmann, Holger; Palosuo, Taru; Ruiz-Ramos, Margarita; Tao, Fulu; Trnka, Miroslav; Acutis, Marco;
2017-01-01
Crop growth simulation models can differ greatly in their treatment of key processes and hence in their response to environmental conditions. Here, we used an ensemble of 26 process-based wheat models applied at sites across a European transect to compare their sensitivity to changes in temperature (minus 2 to plus 9 degrees Centigrade) and precipitation (minus 50 to plus 50 percent). Model results were analysed by plotting them as impact response surfaces (IRSs), classifying the IRS patterns of individual model simulations, describing these classes and analysing factors that may explain the major differences in model responses. The model ensemble was used to simulate yields of winter and spring wheat at four sites in Finland, Germany and Spain. Results were plotted as IRSs that show changes in yields relative to the baseline with respect to temperature and precipitation. IRSs of 30-year means and selected extreme years were classified using two approaches describing their pattern. The expert diagnostic approach (EDA) combines two aspects of IRS patterns: location of the maximum yield (nine classes) and strength of the yield response with respect to climate (four classes), resulting in a total of 36 combined classes defined using criteria pre-specified by experts. The statistical diagnostic approach (SDA) groups IRSs by comparing their pattern and magnitude, without attempting to interpret these features. It applies a hierarchical clustering method, grouping response patterns using a distance metric that combines the spatial correlation and Euclidian distance between IRS pairs. The two approaches were used to investigate whether different patterns of yield response could be related to different properties of the crop models, specifically their genealogy, calibration and process description. Although no single model property across a large model ensemble was found to explain the integrated yield response to temperature and precipitation perturbations, the application of the EDA and SDA approaches revealed their capability to distinguish: (i) stronger yield responses to precipitation for winter wheat than spring wheat; (ii) differing strengths of response to climate changes for years with anomalous weather conditions compared to period-average conditions; (iii) the influence of site conditions on yield patterns; (iv) similarities in IRS patterns among models with related genealogy; (v) similarities in IRS patterns for models with simpler process descriptions of root growth and water uptake compared to those with more complex descriptions; and (vi) a closer correspondence of IRS patterns in models using partitioning schemes to represent yield formation than in those using a harvest index. Such results can inform future crop modelling studies that seek to exploit the diversity of multi-model ensembles, by distinguishing ensemble members that span a wide range of responses as well as those that display implausible behaviour or strong mutual similarities.
-
Diagnostic pathology in 2012: development of digital pathology in an open access journal
2013-01-01
Abstract Herein we describe and interpret the digital world of diagnostic surgical pathology, and take the in Pathology leading Open Access Journal Diagnostic Pathology as example. Virtual slide http://www.diagnosticpathology.diagnomx.eu/vs/1944221953867351 PMID:23305209
-
[Diagnostic yield of video capsule endoscopy in premenopausal women with iron-deficiency anemia].
Garrido Durán, Carmen; Iyo Miyashiro, Eduardo; Páez Cumpa, Claudia; Khorrami Minaei, Sam; Erimeiku Barahona, Alicia; Llompart Rigo, Alfredo
2015-01-01
Clinical practice guidelines recommend video capsule endoscopy (VCE) studies in patients with iron-deficiency anemia (IDA) after conventional upper and lower endoscopies but there is a need for studies demonstrating the diagnostic yield, clinical impact, and cost in some patient subgroups. 1.To determine the diagnostic yield of VCE in premenopausal women with IDA compared with that in men and postmenopausal women. 2. To identify the presence of VCE predictors in premenopausal women. 3. To estimate the cost-clinical impact relationship associated with VCE in this indication. We retrospectively analyzed 408 patients who underwent VCE. Patients with IDA were enrolled (premenopausal, postmenopausal women, and men), with previous normal work-up by conventional endoscopies. A total of 249 patients were enrolled: 131 women (52.6%), of which 51 were premenopausal and 80 were post-menopausal, and 118 men. The mean age was 60.7±16 years. The diagnostic yield of VCE for the diagnosis of IDA was 44.6% (95% CI 39.9 - 50.8). Diagnostic yield was 50.8% vs 38.9% in men vs women (p=0.05) and was 55% vs 13.7% in postmenopausal vs premenopausal women (p<0.001). No predictors of small bowel lesions were found in premenopausal women. The most common findings in the postmenopausal group were angioectasias (70.5%) and erosions (57.1%) in the premenopausal group. The cost in premenopausal women was 44.727€ and 86.3% of the procedures had no clinical impact. The diagnostic yield of VCE is low in the etiological study of IDA in premenopausal women and there is no cost-effectiveness in relation to clinical impact. No predictors of small bowel lesions were found in this group. Copyright © 2015 Elsevier España, S.L.U. and AEEH y AEG. All rights reserved.
-
Vissers, Lisenka E L M; van Nimwegen, Kirsten J M; Schieving, Jolanda H; Kamsteeg, Erik-Jan; Kleefstra, Tjitske; Yntema, Helger G; Pfundt, Rolph; van der Wilt, Gert Jan; Krabbenborg, Lotte; Brunner, Han G; van der Burg, Simone; Grutters, Janneke; Veltman, Joris A; Willemsen, Michèl A A P
2017-09-01
Implementation of novel genetic diagnostic tests is generally driven by technological advances because they promise shorter turnaround times and/or higher diagnostic yields. Other aspects, including impact on clinical management or cost-effectiveness, are often not assessed in detail prior to implementation. We studied the clinical utility of whole-exome sequencing (WES) in complex pediatric neurology in terms of diagnostic yield and costs. We analyzed 150 patients (and their parents) presenting with complex neurological disorders of suspected genetic origin. In a parallel study, all patients received both the standard diagnostic workup (e.g., cerebral imaging, muscle biopsies or lumbar punctures, and sequential gene-by-gene-based testing) and WES simultaneously. Our unique study design allowed direct comparison of diagnostic yield of both trajectories and provided insight into the economic implications of implementing WES in this diagnostic trajectory. We showed that WES identified significantly more conclusive diagnoses (29.3%) than the standard care pathway (7.3%) without incurring higher costs. Exploratory analysis of WES as a first-tier diagnostic test indicates that WES may even be cost-saving, depending on the extent of other tests being omitted. Our data support such a use of WES in pediatric neurology for disorders of presumed genetic origin.Genet Med advance online publication 23 March 2017.
-
Vissers, Lisenka E.L.M.; van Nimwegen, Kirsten J.M.; Schieving, Jolanda H.; Kamsteeg, Erik-Jan; Kleefstra, Tjitske; Yntema, Helger G.; Pfundt, Rolph; van der Wilt, Gert Jan; Krabbenborg, Lotte; Brunner, Han G.; van der Burg, Simone; Grutters, Janneke; Veltman, Joris A.; Willemsen, Michèl A.A.P.
2017-01-01
Purpose: Implementation of novel genetic diagnostic tests is generally driven by technological advances because they promise shorter turnaround times and/or higher diagnostic yields. Other aspects, including impact on clinical management or cost-effectiveness, are often not assessed in detail prior to implementation. Methods: We studied the clinical utility of whole-exome sequencing (WES) in complex pediatric neurology in terms of diagnostic yield and costs. We analyzed 150 patients (and their parents) presenting with complex neurological disorders of suspected genetic origin. In a parallel study, all patients received both the standard diagnostic workup (e.g., cerebral imaging, muscle biopsies or lumbar punctures, and sequential gene-by-gene–based testing) and WES simultaneously. Results: Our unique study design allowed direct comparison of diagnostic yield of both trajectories and provided insight into the economic implications of implementing WES in this diagnostic trajectory. We showed that WES identified significantly more conclusive diagnoses (29.3%) than the standard care pathway (7.3%) without incurring higher costs. Exploratory analysis of WES as a first-tier diagnostic test indicates that WES may even be cost-saving, depending on the extent of other tests being omitted. Conclusion: Our data support such a use of WES in pediatric neurology for disorders of presumed genetic origin. Genet Med advance online publication 23 March 2017 PMID:28333917
-
ERIC Educational Resources Information Center
Reinhold, Simone
2015-01-01
The research presented in this paper focuses on the cognitive diagnostic strategies that prospective elementary mathematics teachers (PTs) use in their reflections of one-on-one diagnostic interviews with children in grade one. Thereby, it responds to the detected lack of knowledge regarding qualitative facets of diagnostic proceeding in interview…
-
De Maio, Peter; White, Lawrence M; Bleakney, Robert; Menezes, Ravi J; Theodoropoulos, John
2014-07-01
To evaluate the diagnostic performance of viewing magnetic resonance (MR) images on a handheld mobile device compared with a conventional radiology workstation for the diagnosis of intra-articular knee pathology. Prospective comparison study. Tertiary care center. Fifty consecutive subjects who had MR imaging of the knee followed by knee arthroscopy were prospectively evaluated. Two musculoskeletal radiologists independently reviewed each MR study using 2 different viewers: the OsiriX DICOM viewer software on an Apple iPhone 3GS device and eFilm Workstation software on a conventional picture archiving and communications system workstation. Sensitivity and specificity of the iPhone and workstation interpretations was performed using knee arthroscopy as the reference standard. Intraobserver concordance and agreement between the iPhone and workstation interpretations were determined. There was no statistically significant difference between the 2 devices for each paired comparison of diagnostic performance. For the iPhone interpretations, sensitivity ranged from 77% (13 of 17) for the lateral meniscus to 100% (17 of 17) for the anterior cruciate ligament. Specificity ranged from 74% (14 of 19) for cartilage to 100% (50 of 50) for the posterior cruciate ligament. There was a very high level of interobserver and intraobserver agreement between devices and readers. The iPhone reads took longer than the corresponding workstation reads, with a significant mean difference between the iPhone and workstation reads of 3.98 minutes (P < 0.001). The diagnostic performance of interpreting MR images on a handheld mobile device for the assessment of intra-articular knee pathology is similar to that of a conventional radiology workstation, however, requires a longer viewing time. Timely and accurate interpretation of complex medical images using mobile device solutions could result in new workflow efficiencies and ultimately improve patient care.
-
Chow, Benjamin J W; Freeman, Michael R; Bowen, James M; Levin, Leslie; Hopkins, Robert B; Provost, Yves; Tarride, Jean-Eric; Dennie, Carole; Cohen, Eric A; Marcuzzi, Dan; Iwanochko, Robert; Moody, Alan R; Paul, Narinder; Parker, John D; O'Reilly, Daria J; Xie, Feng; Goeree, Ron
2011-06-13
Computed tomographic coronary angiography (CTCA) has gained clinical acceptance for the detection of obstructive coronary artery disease. Although single-center studies have demonstrated excellent accuracy, multicenter studies have yielded variable results. The true diagnostic accuracy of CTCA in the "real world" remains uncertain. We conducted a field evaluation comparing multidetector CTCA with invasive CA (ICA) to understand CTCA's diagnostic accuracy in a real-world setting. A multicenter cohort study of patients awaiting ICA was conducted between September 2006 and June 2009. All patients had either a low or an intermediate pretest probability for coronary artery disease and underwent CTCA and ICA within 10 days. The results of CTCA and ICA were interpreted visually by local expert observers who were blinded to all clinical data and imaging results. Using a patient-based analysis (diameter stenosis ≥50%) of 169 patients, the sensitivity, specificity, positive predictive value, and negative predictive value were 81.3% (95% confidence interval [CI], 71.0%-89.1%), 93.3% (95% CI, 85.9%-97.5%), 91.6% (95% CI, 82.5%-96.8%), and 84.7% (95% CI, 76.0%-91.2%), respectively; the area under receiver operating characteristic curve was 0.873. The diagnostic accuracy varied across centers (P < .001), with a sensitivity, specificity, positive predictive value, and negative predictive value ranging from 50.0% to 93.2%, 92.0% to 100%, 84.6% to 100%, and 42.9% to 94.7%, respectively. Compared with ICA, CTCA appears to have good accuracy; however, there was variability in diagnostic accuracy across centers. Factors affecting institutional variability need to be better understood before CTCA is universally adopted. Additional real-world evaluations are needed to fully understand the impact of CTCA on clinical care. clinicaltrials.gov Identifier: NCT00371891.
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Minoshima, S.; Frey, K.A.; Koeppe, R.A.
1995-07-01
To improve the diagnostic performance of PET as an aid in evaluating patients suspected of having Alzheimer`s disease, the authors developed a fully automated method which generates comprehensive image presentations and objective diagnostic indices. Fluorine-18-fluorodeoxyglucose PET image sets were collected from 37 patients with probable Alzheimer`s disease (including questionable and mild dementia), 22 normal subjects and 5 patients with cerebrovascular disease. Following stereotactic anatomic standardization, metabolic activity on an individual`s PET image set was extracted to a set of predefined surface pixels (three-dimensional stereotactic surface projection, 3D-SSP), which was used in the subsequent analysis. A normal database was created bymore » averaging extracted datasets of the normal subjects. Patients` datasets were compared individually with the normal database by calculating a Z-score on a pixel-by-pixel basis and were displayed in 3D-SSP views for visual inspections. Diagnostic indices were then generated based on averaged Z-scores for the association cortices. Patterns and severities of metabolic reduction in patients with probable Alzheimer`s disease were seen in the standard 3D-SSP views of extracted raw data and statistical Z-scores. When discriminating patients with probable Alzheimer`s disease from normal subjects, diagnostic indices of the parietal association cortex and unilaterally averaged parietal-temporal-frontal cortex showed sensitivities of 95% and 97%, respectively, with a specificity of 100%. Neither index yielded false-positive results for cerebrovascular disease. 3D-SSP enables quantitative data extraction and reliable localization of metabolic abnormalities by means of stereotactic coordinates. The proposed method is a promising approach for interpreting functional brain PET scans. 45 refs., 5 figs.« less
-
Pickett, William; Kukaswadia, Atif; Thompson, Wendy; Frechette, Mylene; McFaull, Steven; Dowdall, Hilary; Brison, Robert J
2014-01-01
This study assessed the use and clinical yield of diagnostic imaging (radiography, computed tomography, and medical resonance imaging) ordered to assist in the diagnosis of acute neck injuries presenting to emergency departments (EDs) in Kingston, Ontario, from 2002-2003 to 2009-2010. Acute neck injury cases were identified using records from the Kingston sites of the Canadian National Ambulatory Care Reporting System. Use of radiography was analyzed over time and related to proportions of cases diagnosed with clinically significant cervical spine injuries. A total of 4,712 neck injury cases were identified. Proportions of cases referred for diagnostic imaging to the neck varied significantly over time, from 30.4% in 2002-2003 to 37.6% in 2009-2010 (ptrend = 0.02). The percentage of total cases that were positive for clinically significant cervical spine injury ("clinical yield") also varied from a low of 5.8% in 2005-2006 to 9.2% in 2008-2009 (ptrend = 0.04), although the clinical yield of neck-imaged cases did not increase across the study years (ptrend = 0.23). Increased clinical yield was not observed in association with higher neck imaging rates whether that yield was expressed as a percentage of total cases positive for clinically significant injury (p = 0.29) or as a percentage of neck-imaged cases that were positive (p = 0.77). We observed increases in the use of diagnostic images over time, reflecting a need to reinforce an existing clinical decision rule for cervical spine radiography. Temporal increases in the clinical yield for total cases may suggest a changing case mix or more judicious use of advanced types of diagnostic imaging.
-
Panel-Based Clinical Genetic Testing in 85 Children with Inherited Retinal Disease.
Taylor, Rachel L; Parry, Neil R A; Barton, Stephanie J; Campbell, Christopher; Delaney, Claire M; Ellingford, Jamie M; Hall, Georgina; Hardcastle, Claire; Morarji, Jiten; Nichol, Elisabeth J; Williams, Lindsi C; Douzgou, Sofia; Clayton-Smith, Jill; Ramsden, Simon C; Sharma, Vinod; Biswas, Susmito; Lloyd, I Chris; Ashworth, Jane L; Black, Graeme C; Sergouniotis, Panagiotis I
2017-07-01
To assess the clinical usefulness of genetic testing in a pediatric population with inherited retinal disease (IRD). Single-center retrospective case series. Eighty-five unrelated children with a diagnosis of isolated or syndromic IRD who were referred for clinical genetic testing between January 2014 and July 2016. Participants underwent a detailed ophthalmic examination, accompanied by electrodiagnostic testing (EDT) and dysmorphologic assessment where appropriate. Ocular and extraocular features were recorded using Human Phenotype Ontology terms. Subsequently, multigene panel testing (105 or 177 IRD-associated genes) was performed in an accredited diagnostic laboratory, followed by clinical variant interpretation. Diagnostic yield and clinical usefulness of genetic testing. Overall, 78.8% of patients (n = 67) received a probable molecular diagnosis; 7.5% (n = 5) of these had autosomal dominant disease, 25.4% (n = 17) had X-linked disease, and 67.2% (n = 45) had autosomal recessive disease. In a further 5.9% of patients (n = 5), a single heterozygous ABCA4 variant was identified; all these participants had a spectrum of clinical features consistent with ABCA4 retinopathy. Most participants (84.7%; n = 72) had undergone EDT and 81.9% (n = 59) of these patients received a probable molecular diagnosis. The genes most frequently mutated in the present cohort were CACNA1F and ABCA4, accounting for 14.9% (n = 10) and 11.9% (n = 8) of diagnoses respectively. Notably, in many cases, genetic testing helped to distinguish stationary from progressive IRD subtypes and to establish a precise diagnosis in a timely fashion. Multigene panel testing pointed to a molecular diagnosis in 84.7% of children with IRD. The diagnostic yield in the study population was significantly higher compared with that in previously reported unselected IRD cohorts. Approaches similar to the one described herein are expected to become a standard component of care in pediatric ophthalmology. We propose the introduction of genetic testing early in the diagnostic pathway in children with clinical and/or electrophysiologic findings, suggestive of IRD. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
-
A novel molecular diagnostics platform for somatic and germline precision oncology.
Cabanillas, Rubén; Diñeiro, Marta; Castillo, David; Pruneda, Patricia C; Penas, Cristina; Cifuentes, Guadalupe A; de Vicente, Álvaro; Durán, Noelia S; Álvarez, Rebeca; Ordóñez, Gonzalo R; Cadiñanos, Juan
2017-07-01
Next-generation sequencing (NGS) opens new options in clinical oncology, from therapy selection to genetic counseling. However, realization of this potential not only requires succeeding in the bioinformatics and interpretation of the results, but also in their integration into the clinical practice. We have developed a novel NGS diagnostic platform aimed at detecting (1) somatic genomic alterations associated with the response to approved targeted cancer therapies and (2) germline mutations predisposing to hereditary malignancies. Next-generation sequencing libraries enriched in the exons of 215 cancer genes (97 for therapy selection and 148 for predisposition, with 30 informative for both applications), as well as selected introns from 17 genes involved in drug-related rearrangements, were prepared from 39 tumors (paraffin-embedded tissues/cytologies), 36 germline samples (blood) and 10 cell lines using hybrid capture. Analysis of NGS results was performed with specifically developed bioinformatics pipelines. The platform detects single-nucleotide variants (SNVs) and insertions/deletions (indels) with sensitivity and specificity >99.5% (allelic frequency ≥0.1), as well as copy-number variants (CNVs) and rearrangements. Somatic testing identified tailored approved targeted drugs in 35/39 tumors (89.74%), showing a diagnostic yield comparable to that of leading commercial platforms. A somatic EGFR p.E746_S752delinsA mutation in a mediastinal metastasis from a breast cancer prompted its anatomopathologic reassessment, its definite reclassification as a lung cancer and its treatment with gefitinib (partial response sustained for 15 months). Testing of 36 germline samples identified two pathogenic mutations (in CDKN2A and BRCA2 ). We propose a strategy for interpretation and reporting of results adaptable to the aim of the request, the availability of tumor and/or normal samples and the scope of the informed consent. With an adequate methodology, it is possible to translate to the clinical practice the latest advances in precision oncology, integrating under the same platform the identification of somatic and germline genomic alterations.
-
Yarmus, Lonny B; Akulian, Jason; Lechtzin, Noah; Yasin, Faiza; Kamdar, Biren; Ernst, Armin; Ost, David E; Ray, Cynthia; Greenhill, Sarah R; Jimenez, Carlos A; Filner, Joshua; Feller-Kopman, David
2013-04-01
Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure originally performed using a 22-gauge (22G) needle. A recently introduced 21-gauge (21G) needle may improve the diagnostic yield and sample adequacy of EBUS-TBNA, but prior smaller studies have shown conflicting results. To our knowledge, this is the largest study undertaken to date to determine whether the 21G needle adds diagnostic benefit. We retrospectively evaluated the results of 1,299 patients from the American College of Chest Physicians Quality Improvement Registry, Education, and Evaluation (AQuIRE) Diagnostic Registry who underwent EBUS-TBNA between February 2009 and September 2010 at six centers throughout the United States. Data collection included patient demographics, sample adequacy, and diagnostic yield. Analysis consisted of univariate and multivariate hierarchical logistic regression comparing diagnostic yield and sample adequacy of EBUS-TBNA specimens by needle gauge. A total of 1,235 patients met inclusion criteria. Sample adequacy was obtained in 94.9% of the 22G needle group and in 94.6% of the 21G needle group (P = .81). A diagnosis was made in 51.4% of the 22G and 51.3% of the 21G groups (P = .98). Multivariate hierarchical logistic regression showed no statistical difference in sample adequacy or diagnostic yield between the two groups. The presence of rapid onsite cytologic evaluation was associated with significantly fewer needle passes per procedure when using the 21G needle (P < .001). There is no difference in specimen adequacy or diagnostic yield between the 21G and 22G needle groups. EBUS-TBNA in conjunction with rapid onsite cytologic evaluation and a 21G needle is associated with fewer needle passes compared with a 22G needle.
-
NASA Astrophysics Data System (ADS)
Sun, Xiaobin; Xu, Yongxin; Lin, Lixiang
2015-05-01
Parameter estimates of artesian aquifers where piezometric head is above ground level are largely made through free-flowing and recovery tests. The straight-line method proposed by Jacob-Lohman is often used for interpretation of flow rate measured at flowing artesian boreholes. However, the approach fails to interpret the free-flowing test data from two artesian boreholes in the fractured-rock aquifer in Table Mountain Group (TMG) of South Africa. The diagnostic plot method using the reciprocal rate derivative is adapted to evaluate the artesian aquifer properties. The variation of the derivative helps not only identify flow regimes and discern the boundary conditions, but also facilitates conceptualization of the aquifer system and selection of an appropriate model for data interpretation later on. Test data from two free-flowing tests conducted in different sites in TMG are analysed using the diagnostic plot method. Based on the results, conceptual models and appropriate approaches are developed to evaluate the aquifer properties. The advantages and limitations of using the diagnostic plot method on free-flowing test data are discussed.
-
Peace, Aaron; Ramsewak, Adesh; Cairns, Andrew; Finlay, Dewar; Guldenring, Daniel; Clifford, Gari; Bond, Raymond
2015-01-01
The 12-lead electrocardiogram (ECG) is a crucial diagnostic tool. However, the ideal method to assess competency in ECG interpretation remains unclear. We sought to evaluate whether keypad response technology provides a rapid, interactive way to assess ECG knowledge. 75 participants were enrolled [32 (43%) Primary Care Physicians, 24 (32%) Hospital Medical Staff and 19 (25%) Nurse Practitioners]. Nineteen ECGs with 4 possible answers were interpreted. Out of 1425 possible decisions 1054 (73.9%) responses were made. Only 570/1425 (40%) of the responses were correct. Diagnostic accuracy varied (0% to 78%, mean 42%±21%) across the entire cohort. Participation was high, (median 83%, IQR 50%-100%). Hospital Medical Staff had significantly higher diagnostic accuracy than nurse practitioners (50±20% vs. 38±19%, p=0.04) and Primary Care Physicians (50±20% vs. 40±21%, p=0.07) although not significant. Interactive voting systems can be rapidly and successfully used to assess ECG interpretation. Further education is necessary to improve diagnostic accuracy. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
-
[Diagnostic rentability of close pleural biopsy: Tru-cut vs. Cope].
Valdez-López, Héctor Glenn; Cano-Rodríguez, Alma Iris; Montemayor-Chapa, Mario; Castillo-Sánchez, Juan Francisco
2018-01-01
The prevalence of pleural effusion in Mexico is over 400 per 100 000 inhabitants. The etiology is infectious in 45.7% and neoplastic in 32.6%. Closed pleural biopsy sensibility is 48-70% in cancer and 50-59% in tuberculosis using Cope or Abrams needle. In 1989, Tru-cut needle biopsy was described in a small study for massive pleural effusions with a sensibility of 86%. Our Institute has a wide experience with this infrequently procedure with reliable results than using Cope needle. Diagnostic yield should be evaluated. We aimed to evaluate the diagnostic yield of Tru-cut vs. standard Cope biopsy in the histopathological diagnosis of pleural effusion. Experimental, not blinded, analytical, cross-sectional study. We studied 44 patients (24 male and 20 female) with exudative pleural effusion over a period of 14 months. Every patient underwent four Tru-cut and four Cope needle biopsies. The diagnostic yield of both methods was compared. The mean age of patients was 61.4 ± 12.2 years. The diagnosis was achieved in 25 (57%) of patients using Tru-cut and 22 (50%) of patients using Cope's closed pleural biopsy. The diagnostic value was not significantly higher (p = 0.41). The most common diagnoses were adenocarcinoma (20.5%), mesothelioma (15.9%) and tuberculosis (15.9%). The diagnostic yield of Tru-cut needle biopsy is slightly higher than Cope pleural biopsy, very similar to that reported previously. The experience in this procedure is an advantage in our clinical practice.
-
Jackson, Sara L.; Frederick, Paul D.; Pepe, Margaret S.; Nelson, Heidi D.; Weaver, Donald L.; Allison, Kimberly H.; Carney, Patricia A.; Geller, Berta M.; Tosteson, Anna N. A.; Onega, Tracy; Elmore, Joann G.
2017-01-01
Background Surgeons may receive a different diagnosis when a breast biopsy is interpreted by a second pathologist. The extent to which diagnostic agreement by the same pathologist varies at two time points is unknown. Participants and Methods Pathologists from 8 U.S. states independently interpreted 60 breast specimens, one glass slide per case, on 2 occasions separated by ≥9 months. Reproducibility was assessed by comparing interpretations between the two time points; associations between reproducibility (intra-observer agreement rates) and characteristics of pathologists and cases were determined and also compared with inter-observer agreement of baseline interpretations. Results Sixty-five percent of invited, responding pathologists were eligible and consented; 49 interpreted glass slides in both study phases resulting in 2,940 interpretations. Intra-observer agreement rates between the two phases were 92% (95% CI 88%-95%) for invasive breast cancer, 84% (95% CI 81%-87%) for ductal carcinoma in situ (DCIS), 53% (95% CI 47%-59%) for atypia, and 84% (95% CI 81%-86%) for benign without atypia. When comparing all study participants' case interpretations at baseline, inter-observer agreement rates were 89% (95% CI 84%-92%) for invasive cancer, 79% (95% CI 76%-81%) for DCIS, 43% (95% CI 41%-45%) for atypia, and 77% (95% CI 74%-79%) for benign without atypia. Conclusions Interpretive agreement between two time points by the same individual pathologists was low for atypia, and similar to observed rates of agreement for atypia between different pathologists. Physicians and patients should be aware of the diagnostic challenges associated with a breast biopsy diagnosis of atypia when considering treatment and surveillance decisions. PMID:27913946
-
Jackson, Sara L; Frederick, Paul D; Pepe, Margaret S; Nelson, Heidi D; Weaver, Donald L; Allison, Kimberly H; Carney, Patricia A; Geller, Berta M; Tosteson, Anna N A; Onega, Tracy; Elmore, Joann G
2017-05-01
Surgeons may receive a different diagnosis when a breast biopsy is interpreted by a second pathologist. The extent to which diagnostic agreement by the same pathologist varies at two time points is unknown. Pathologists from eight U.S. states independently interpreted 60 breast specimens, one glass slide per case, on two occasions separated by ≥9 months. Reproducibility was assessed by comparing interpretations between the two time points; associations between reproducibility (intraobserver agreement rates); and characteristics of pathologists and cases were determined and also compared with interobserver agreement of baseline interpretations. Sixty-five percent of invited, responding pathologists were eligible and consented; 49 interpreted glass slides in both study phases, resulting in 2940 interpretations. Intraobserver agreement rates between the two phases were 92% [95% confidence interval (CI) 88-95] for invasive breast cancer, 84% (95% CI 81-87) for ductal carcinoma-in-situ, 53% (95% CI 47-59) for atypia, and 84% (95% CI 81-86) for benign without atypia. When comparing all study participants' case interpretations at baseline, interobserver agreement rates were 89% (95% CI 84-92) for invasive cancer, 79% (95% CI 76-81) for ductal carcinoma-in-situ, 43% (95% CI 41-45) for atypia, and 77% (95% CI 74-79) for benign without atypia. Interpretive agreement between two time points by the same individual pathologist was low for atypia and was similar to observed rates of agreement for atypia between different pathologists. Physicians and patients should be aware of the diagnostic challenges associated with a breast biopsy diagnosis of atypia when considering treatment and surveillance decisions.
-
Córdoba, Marta; Rodriguez-Quiroga, Sergio Alejandro; Vega, Patricia Analía; Salinas, Valeria; Perez-Maturo, Josefina; Amartino, Hernán; Vásquez-Dusefante, Cecilia; Medina, Nancy; González-Morón, Dolores; Kauffman, Marcelo Andrés
2018-01-01
Diagnostic trajectories for neurogenetic disorders frequently require the use of considerable time and resources, exposing patients and families to so-called "diagnostic odysseys". Previous studies have provided strong evidence for increased diagnostic and clinical utility of whole-exome sequencing in medical genetics. However, specific reports assessing its utility in a setting such as ours- a neurogeneticist led academic group serving in a low-income country-are rare. To assess the diagnostic yield of WES in patients suspected of having a neurogenetic condition and explore the cost-effectiveness of its implementation in a research group located in an Argentinean public hospital. This is a prospective study of the clinical utility of WES in a series of 40 consecutive patients selected from a Neurogenetic Clinic of a tertiary Hospital in Argentina. We evaluated patients retrospectively for previous diagnostic trajectories. Diagnostic yield, clinical impact on management and economic diagnostic burden were evaluated. We demonstrated the clinical utility of Whole Exome Sequencing in our patient cohort, obtaining a diagnostic yield of 40% (95% CI, 24.8%-55.2%) among a diverse group of neurological disorders. The average age at the time of WES was 23 (range 3-70). The mean time elapsed from symptom onset to WES was 11 years (range 3-42). The mean cost of the diagnostic workup prior to WES was USD 1646 (USD 1439 to 1853), which is 60% higher than WES cost in our center. WES for neurogenetics proved to be an effective, cost- and time-saving approach for the molecular diagnosis of this heterogeneous and complex group of patients.
-
Diagnosis and treatment of histoplasmosis in solid organ transplant patients.
Gajurel, Kiran; Dhakal, Reshika; Deresinski, Stan
2018-05-05
Unlike immunocompetent hosts, solid organ transplant (SOT) recipients with posttransplant histoplasmosis (PTH) often present with disseminated disease and have an attributable mortality of approximately 10%. In this review, we discuss currently available diagnostic tests and treatment strategies in PTH. None of the available tests have a 100% diagnostic accuracy. Histoplasma antigen assays are the most sensitive commercially available tests. However, crossreactivity of histoplasma antigen with aspergillus galactomannan and false positive histoplasma antigen tests because of rabbit antithymocyte globulin may cause difficulty in interpreting positive test results in transplant recipients. Molecular assays such as amplification and sequencing of 'panfungal' portions of the 28S ribosomal RNA from clinical specimens appear to be promising.Lipid formulations of amphotericin B and itraconazole are the drugs of choice in the treatment of PTH. Other extended spectrum azoles also appear to be effective, but, like itraconazole, problems with drug interactions and prolongation of the QTc interval (except for isavuconazole, which shortens the QTc interval) remain. Mycophenolate therapy is associated with severe disease and should be stopped during active disease and, if feasible, calcineurin inhibitors and steroids should be reduced. A combination of various tests (culture, antigen tests, nucleic amplification tests, etc.) should be used to optimize diagnostic yield. The role of unbiased next generation sequencing for early diagnosis and newer azoles in the treatment needs to be further explored.
-
Nendaz, Mathieu R; Gut, Anne M; Perrier, Arnaud; Louis-Simonet, Martine; Blondon-Choa, Katherine; Herrmann, François R; Junod, Alain F; Vu, Nu V
2006-01-01
BACKGROUND Clinical experience, features of data collection process, or both, affect diagnostic accuracy, but their respective role is unclear. OBJECTIVE, DESIGN Prospective, observational study, to determine the respective contribution of clinical experience and data collection features to diagnostic accuracy. METHODS Six Internists, 6 second year internal medicine residents, and 6 senior medical students worked up the same 7 cases with a standardized patient. Each encounter was audiotaped and immediately assessed by the subjects who indicated the reasons underlying their data collection. We analyzed the encounters according to diagnostic accuracy, information collected, organ systems explored, diagnoses evaluated, and final decisions made, and we determined predictors of diagnostic accuracy by logistic regression models. RESULTS Several features significantly predicted diagnostic accuracy after correction for clinical experience: early exploration of correct diagnosis (odds ratio [OR] 24.35) or of relevant diagnostic hypotheses (OR 2.22) to frame clinical data collection, larger number of diagnostic hypotheses evaluated (OR 1.08), and collection of relevant clinical data (OR 1.19). CONCLUSION Some features of data collection and interpretation are related to diagnostic accuracy beyond clinical experience and should be explicitly included in clinical training and modeled by clinical teachers. Thoroughness in data collection should not be considered a privileged way to diagnostic success. PMID:17105525
-
Student Interpretations of Diagnostic Feedback
ERIC Educational Resources Information Center
Doe, Christine
2015-01-01
Diagnostic assessment is increasingly being recognized as a potentially beneficial tool for teaching and learning (Jang, 2012). There have been calls in the research literature for students to receive diagnostic feedback and for researchers to investigate how such feedback is used by students. Therefore, this study examined how students…
-
7T MRI in focal epilepsy with unrevealing conventional field strength imaging.
De Ciantis, Alessio; Barba, Carmen; Tassi, Laura; Cosottini, Mirco; Tosetti, Michela; Costagli, Mauro; Bramerio, Manuela; Bartolini, Emanuele; Biagi, Laura; Cossu, Massimo; Pelliccia, Veronica; Symms, Mark R; Guerrini, Renzo
2016-03-01
To assess the diagnostic yield of 7T magnetic resonance imaging (MRI) in detecting and characterizing structural lesions in patients with intractable focal epilepsy and unrevealing conventional (1.5 or 3T) MRI. We conducted an observational clinical imaging study on 21 patients (17 adults and 4 children) with intractable focal epilepsy, exhibiting clinical and electroencephalographic features consistent with a single seizure-onset zone (SOZ) and unrevealing conventional MRI. Patients were enrolled at two tertiary epilepsy surgery centers and imaged at 7T, including whole brain (three-dimensional [3D] T1 -weighted [T1W] fast-spoiled gradient echo (FSPGR), 3D susceptibility-weighted angiography [SWAN], 3D fluid-attenuated inversion recovery [FLAIR]) and targeted imaging (2D T2*-weighted dual-echo gradient-recalled echo [GRE] and 2D gray-white matter tissue border enhancement [TBE] fast spin echo inversion recovery [FSE-IR]). MRI studies at 1.5 or 3T deemed unrevealing at the referral center were reviewed by three experts in epilepsy imaging. Reviewers were provided information regarding the suspected localization of the SOZ. The same team subsequently reviewed 7T images. Agreement in imaging interpretation was reached through consensus-based discussions based on visual identification of structural abnormalities and their likely correlation with clinical and electrographic data. 7T MRI revealed structural lesions in 6 (29%) of 21 patients. The diagnostic gain in detection was obtained using GRE and FLAIR images. Four of the six patients with abnormal 7T underwent epilepsy surgery. Histopathology revealed focal cortical dysplasia (FCD) in all. In the remaining 15 patients (71%), 7T MRI remained unrevealing; 4 of the patients underwent epilepsy surgery and histopathologic evaluation revealed gliosis. 7T MRI improves detection of epileptogenic FCD that is not visible at conventional field strengths. A dedicated protocol including whole brain FLAIR and GRE images at 7T targeted at the suspected SOZ increases the diagnostic yield. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.
-
Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments
Hatarik, R.; Sayre, D. B.; Caggiano, J. A.; ...
2015-11-12
For a long time, neutron time-of-flight diagnostics been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d+t→n+α (DT) and d+d→n+³He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, which is also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (T ion) and cold fuel areal density. We explain such novel methodologies used to determine neutron yield, apparent T ion and DSR.
-
Dual-energy CT for the diagnosis of gout: an accuracy and diagnostic yield study.
Bongartz, Tim; Glazebrook, Katrina N; Kavros, Steven J; Murthy, Naveen S; Merry, Stephen P; Franz, Walter B; Michet, Clement J; Veetil, Barath M Akkara; Davis, John M; Mason, Thomas G; Warrington, Kenneth J; Ytterberg, Steven R; Matteson, Eric L; Crowson, Cynthia S; Leng, Shuai; McCollough, Cynthia H
2015-06-01
To assess the accuracy of dual-energy CT (DECT) for diagnosing gout, and to explore whether it can have any impact on clinical decision making beyond the established diagnostic approach using polarising microscopy of synovial fluid (diagnostic yield). Diagnostic single-centre study of 40 patients with active gout, and 41 individuals with other types of joint disease. Sensitivity and specificity of DECT for diagnosing gout was calculated against a combined reference standard (polarising and electron microscopy of synovial fluid). To explore the diagnostic yield of DECT scanning, a third cohort was assembled consisting of patients with inflammatory arthritis and risk factors for gout who had negative synovial fluid polarising microscopy results. Among these patients, the proportion of subjects with DECT findings indicating a diagnosis of gout was assessed. The sensitivity and specificity of DECT for diagnosing gout was 0.90 (95% CI 0.76 to 0.97) and 0.83 (95% CI 0.68 to 0.93), respectively. All false negative patients were observed among patients with acute, recent-onset gout. All false positive patients had advanced knee osteoarthritis. DECT in the diagnostic yield cohort revealed evidence of uric acid deposition in 14 out of 30 patients (46.7%). DECT provides good diagnostic accuracy for detection of monosodium urate (MSU) deposits in patients with gout. However, sensitivity is lower in patients with recent-onset disease. DECT has a significant impact on clinical decision making when gout is suspected, but polarising microscopy of synovial fluid fails to demonstrate the presence of MSU crystals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
-
Some diagnostic interpretations from railgun plasma profile experiments
NASA Astrophysics Data System (ADS)
Stainsby, D. F.; Bedford, A. J.
1984-03-01
Some aspects of a railgun experimental series to investigate plasma profiles are reviewed. Certain diagnostic records clearly show plasma leakage past the projectile, and correspondence between various in-bore events and muzzle voltage. A muzzle flash detector is shown to have a useful role as a plasma diagnostic tool.
-
Comparison of Sample Adequacy and Diagnostic Yield of 19- and 22-G EBUS-TBNA Needles.
Chaddha, Udit; Ronaghi, Reza; Elatre, Waafa; Chang, Ching-Fei; Mahdavi, Ramyar
2018-05-16
The 2016 CHEST consensus guidelines recommend use of either 21- or 22-G needles for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). We decided to prospectively compare sample adequacy and diagnostic yield of the 19-G with the 22-G EBUS needle, hypothesizing that a larger gauge difference might magnify the differences between 2 needle sizes. Twenty-seven patients undergoing EBUS-TBNA at our institution were evaluated. All cases were performed by a single operator formally trained in interventional pulmonology. Both Olympus 19- and 22-G needles were used at each lymph node station in an alternating manner. Rapid on-site cytology evaluation was used and a separate cell block was prepared for each needle at each station. Fifty-six lymph nodes were analyzed. Diagnoses included cancer (36%, including 1 lymphoma), reactive lymphoid tissue (53%), and sarcoidosis (11%). One hundred sixty-two and 163 passes were made with the 22- and 19-G needle, respectively. Sample adequacy was 73% and 46% with the 22 and 19-G needle, respectively (P<0.001). Significantly fewer passes were bloody with the 22-G compared with the 19-G needle (19% vs. 59%; P<0.001). Diagnostic yield was not different between the 22- and 19-G needles (95% vs. 93%; P=0.62). In addition to no difference in diagnostic yield, the 19-G needle yielded samples that were frequently less adequate and more often bloody compared with the 22-G needle. Despite the larger caliber lumen, we conclude that the 19-G needle does not confer a diagnostic advantage.
-
Incorporating uncertainty into medical decision making: an approach to unexpected test results.
Bianchi, Matt T; Alexander, Brian M; Cash, Sydney S
2009-01-01
The utility of diagnostic tests derives from the ability to translate the population concepts of sensitivity and specificity into information that will be useful for the individual patient: the predictive value of the result. As the array of available diagnostic testing broadens, there is a temptation to de-emphasize history and physical findings and defer to the objective rigor of technology. However, diagnostic test interpretation is not always straightforward. One significant barrier to routine use of probability-based test interpretation is the uncertainty inherent in pretest probability estimation, the critical first step of Bayesian reasoning. The context in which this uncertainty presents the greatest challenge is when test results oppose clinical judgment. It is this situation when decision support would be most helpful. The authors propose a simple graphical approach that incorporates uncertainty in pretest probability and has specific application to the interpretation of unexpected results. This method quantitatively demonstrates how uncertainty in disease probability may be amplified when test results are unexpected (opposing clinical judgment), even for tests with high sensitivity and specificity. The authors provide a simple nomogram for determining whether an unexpected test result suggests that one should "switch diagnostic sides.'' This graphical framework overcomes the limitation of pretest probability uncertainty in Bayesian analysis and guides decision making when it is most challenging: interpretation of unexpected test results.
-
Gonzalez, Araceli; Rozenman, Michelle; Langley, Audra K; Kendall, Philip C; Ginsburg, Golda S; Compton, Scott; Walkup, John T; Birmaher, Boris; Albano, Anne Marie; Piacentini, John
2017-06-01
Anxiety disorders are among the most common mental health problems in youth, and faulty interpretation bias has been positively linked to anxiety severity, even within anxiety-disordered youth. Quick, reliable assessment of interpretation bias may be useful in identifying youth with certain types of anxiety or assessing changes on cognitive bias during intervention. This study examined the factor structure, reliability, and validity of the Self-report of Ambiguous Social Situations for Youth (SASSY) scale, a self-report measure developed to assess interpretation bias in youth. Participants (N=488, age 7 to 17) met diagnostic criteria for Social Phobia, Generalized Anxiety Disorder, and/or Separation Anxiety Disorder. An exploratory factor analysis was performed on baseline data from youth participating in a large randomized clinical trial. Exploratory factor analysis yielded two factors (Accusation/Blame, Social Rejection). The SASSY full scale and Social Rejection factor demonstrated adequate internal consistency, convergent validity with social anxiety, and discriminant validity as evidenced by non-significant correlations with measures of non-social anxiety. Further, the SASSY Social Rejection factor accurately distinguished children and adolescents with Social Phobia from those with other anxiety disorders, supporting its criterion validity, and revealed sensitivity to changes with treatment. Given the relevance to youth with social phobia, pre- and post-intervention data were examined for youth social phobia to test sensitivity to treatment effects; results suggested that SASSY scores reduced for treatment responders. Findings suggest the potential utility of the SASSY Social Rejection factor as a quick, reliable, and efficient way of assessing interpretation bias in anxious youth, particularly as related to social concerns, in research and clinical settings.
-
Aarsand, Aasne K; Villanger, Jørild H; Støle, Egil; Deybach, Jean-Charles; Marsden, Joanne; To-Figueras, Jordi; Badminton, Mike; Elder, George H; Sandberg, Sverre
2011-11-01
The porphyrias are a group of rare metabolic disorders whose diagnosis depends on identification of specific patterns of porphyrin precursor and porphyrin accumulation in urine, blood, and feces. Diagnostic tests for porphyria are performed by specialized laboratories in many countries. Data regarding the analytical and diagnostic performance of these laboratories are scarce. We distributed 5 sets of multispecimen samples from different porphyria patients accompanied by clinical case histories to 18-21 European specialist porphyria laboratories/centers as part of a European Porphyria Network organized external analytical and postanalytical quality assessment (EQA) program. The laboratories stated which analyses they would normally have performed given the case histories and reported results of all porphyria-related analyses available, interpretative comments, and diagnoses. Reported diagnostic strategies initially showed considerable diversity, but the number of laboratories applying adequate diagnostic strategies increased during the study period. We found an average interlaboratory CV of 50% (range 12%-152%) for analytes in absolute concentrations. Result normalization by forming ratios to the upper reference limits did not reduce this variation. Sixty-five percent of reported results were within biological variation-based analytical quality specifications. Clinical interpretation of the obtained analytical results was accurate, and most laboratories established the correct diagnosis in all distributions. Based on a case-based EQA scheme, variations were apparent in analytical and diagnostic performance between European specialist porphyria laboratories. Our findings reinforce the use of EQA schemes as an essential tool to assess both analytical and diagnostic processes and thereby to improve patient care in rare diseases.
-
ERIC Educational Resources Information Center
Al-Mamari, Watfa; Al-Saegh, Abeer; Al-Kindy, Adila; Bruwer, Zandre; Al-Murshedi, Fathiya; Al-Thihli, Khalid
2015-01-01
Autism Spectrum Disorders are a complicated group of disorders characterized with heterogeneous genetic etiologies. The genetic investigations for this group of disorders have expanded considerably over the past decade. In our study we designed a tired approach and studied the diagnostic yield of chromosomal microarray analysis on patients…
-
Ho, Dora Y; Lin, Margaret; Schaenman, Joanna; Rosso, Fernando; Leung, Ann N C; Coutre, Steven E; Sista, Ramachandra R; Montoya, Jose G
2011-01-01
Haematological patients with neutropenic fever are frequently evaluated with chest computed tomography (CT) to rule out invasive fungal infections (IFI). We retrospectively analysed data from 100 consecutive patients with neutropenic fever and abnormal chest CT from 1998 to 2005 to evaluate their chest CT findings and the yield of diagnostic approaches employed. For their initial CTs, 79% had nodular opacities, with 24.1% associated with the halo sign. Other common CT abnormalities included pleural effusions (48%), ground glass opacities (37%) and consolidation (31%). The CT findings led to a change in antifungal therapy in 54% of the patients. Fifty-six patients received diagnostic procedures, including 46 bronchoscopies, 25 lung biopsies and seven sinus biopsies, with a diagnostic yield for IFI of 12.8%, 35.0% and 83.3%, respectively. In conclusion, chest CT plays an important role in the evaluation of haematological patients with febrile neutropenia and often leads to a change in antimicrobial therapy. Pulmonary nodules are the most common radiological abnormality. Sinus or lung biopsies have a high-diagnostic yield for IFI as compared to bronchoscopy. Patients with IFI may not have sinus/chest symptoms, and thus, clinicians should have a low threshold for performing sinus/chest imaging, and if indicated and safe, a biopsy of the abnormal areas. © 2009 Blackwell Verlag GmbH.
-
Recent sheath physics studies on DIII-D
NASA Astrophysics Data System (ADS)
Watkins, J. G.; Labombard, B.; Stangeby, P. C.; Lasnier, C. J.; McLean, A. G.; Nygren, R. E.; Boedo, J. A.; Leonard, A. W.; Rudakov, D. L.
2015-08-01
A study to examine some current issues in the physics of the plasma sheath has been recently carried out in DIII-D low power Ohmic plasmas using both flush and domed Langmuir probes, divertor Thomson scattering (DTS), an infrared camera (IRTV), and a new calorimeter triple probe assembly mounted on the Divertor Materials Evaluation System (DIMES). The sheath power transmission factor was found to be consistent with the theoretically predicted value of 7 (±2) for low power plasmas. Using this factor, the three heat flux profiles derived from the LP, DTS, and calorimeter diagnostic measurements agree. Comparison of flush and domed Langmuir probes and divertor Thomson scattering indicates that proper interpretation of flush probe data to get target plate density and temperature is feasible and could potentially yield accurate measurements of target plate conditions where the probes are located.
-
NASA Astrophysics Data System (ADS)
Neelin, J.; Langenbrunner, B.; Meyerson, J. E.
2012-12-01
Precipitation changes under global warming are often discussed in terms of wet areas receiving more precipitation and dry areas receiving less, sometimes termed the "rich-get-richer" effect. Since the first use of this term, it has been known that contributions can be broken diagnostically into a relatively straightforward tendency associated with moisture increases acted on by the climatological circulation and dynamical feedbacks associated with changes in circulation. A number of studies indicate the latter to be prone to yield scatter in model projections of precipitation change. At the spatial scales of the major monsoon regions, substantial contributions from dynamical feedbacks tend to occur. Factors affecting this dependence will be reviewed with an eye to asking how the community can make succinct statements without oversimplifying the challenges at the regional scale.
-
Bronchoalveolar lavage in malignancy.
Poletti, Venerino; Poletti, Giovanni; Murer, Bruno; Saragoni, Luca; Chilosi, Marco
2007-10-01
Bronchoalveolar lavage is a useful diagnostic tool in diffuse or disseminated lung malignancies that do not involve the bronchial structures visible by endoscopy. The neoplastic histotype and the intraparenchymal neoplastic growth pattern are good predictors for diagnostic yield; adenocarcinoma, and tumors with lymphangitic or lepidic growth patterns are more easily diagnosed by bronchoalveolar lavage; in these cases the diagnostic yield reported is higher than 80%. In hematologic malignancies the diagnostic yield is quite good in secondary diffuse indolent B cell lymphomas and in primary B cell lymphomas of mucosa-associated lymphoid tissue (MALT) type but low in Hodgkin disease. Morphological analysis may be implemented by immunocytochemical or molecular tests to identify the cell lineage and the presence of monoclonality. Disorders in which bronchioloalveolar cell hyperplasia/dysplasia is a significant morphological component may have cytological features in bronchoalveolar lavage fluid that mimic lung neoplasms: acute respiratory distress syndrome (ARDS), acute interstitial pneumonitis (AIP), and acute exacerbation of idiopathic pulmonary fibrosis are the most important clinical entities in this group.
-
Delfiner, Matthew S; Martinez, Luis R; Pavia, Charles S
2016-01-01
Laboratory diagnostic tests have an essential role in patient care, and the increasing number of medical and health professions schools focusing on teaching laboratory medicine to pre-clinical students reflects this importance. However, data validating the pedagogical methods that best influence students' comprehension and interpretation of diagnostic tests have not been well described. The Gram stain is a simple yet significant and frequently used diagnostic test in the clinical setting that helps classify bacteria into two major groups, Gram positive and negative, based on their cell wall structure. We used this technique to assess which educational strategies may improve students' learning and competency in medical diagnostic techniques. Hence, in this randomized controlled study, we compared the effectiveness of several educational strategies (e.g. workshop, discussion, or lecture) in first year medical students' competency in comprehension and interpretation of the Gram stain procedure. We demonstrated that a hands-on practical workshop significantly enhances students' competency in memorization and overall comprehension of the technique. Interestingly, most students irrespective of their cohort showed difficulty in answering Gram stain-related analytical questions, suggesting that more emphasis should be allocated by the instructors to clearly explain the interpretation of the diagnostic test results to students in medical and health professional schools. This proof of principle study highlights the need of practical experiences on laboratory medical techniques during pre-clinical training to facilitate future medical doctors' and healthcare professionals' basic understanding and competency in diagnostic testing for better patient care.
-
Clinical decision making using teleradiology in urology.
Lee, B R; Allaf, M; Moore, R; Bohlman, M; Wang, G M; Bishoff, J T; Jackman, S V; Cadeddu, J A; Jarrett, T W; Khazan, R; Kavoussi, L R
1999-01-01
Using a personal computer-based teleradiology system, we compared accuracy, confidence, and diagnostic ability in the interpretation of digitized radiographs to determine if teleradiology-imported studies convey sufficient information to make relevant clinical decisions involving urology. Variables of diagnostic accuracy, confidence, image quality, interpretation, and the impact of clinical decisions made after viewing digitized radiographs were compared with those of original radiographs. We evaluated 956 radiographs that included 94 IV pyelograms, four voiding cystourethrograms, and two nephrostograms. The radiographs were digitized and transferred over an Ethernet network to a remote personal computer-based viewing station. The digitized images were viewed by urologists and graded according to confidence in making a diagnosis, image quality, diagnostic difficulty, clinical management based on the image itself, and brief patient history. The hard-copy radiographs were then interpreted immediately afterward, and diagnostic decisions were reassessed. All analog radiographs were reviewed by an attending radiologist. Ninety-seven percent of the decisions made from the digitized radiographs did not change after reviewing conventional radiographs of the same case. When comparing the variables of clinical confidence, quality of the film on the teleradiology system versus analog films, and diagnostic difficulty, we found no statistical difference (p > .05) between the two techniques. Overall accuracy in interpreting the digitized images on the teleradiology system was 88% by urologists compared with that of the attending radiologist's interpretation of the analog radiographs. However, urologists detected findings on five (5%) analog radiographs that had been previously unreported by the radiologist. Viewing radiographs transmitted to a personal computer-based viewing station is an appropriate means of reviewing films with sufficient quality on which to base clinical decisions. Our focus was whether decisions made after viewing the transmitted radiographs would change after viewing the hard-copy images of the same case. In 97% of the cases, the decision did not change. In those cases in which management was altered, recommendation of further imaging studies was the most common factor.
-
ERIC Educational Resources Information Center
Jang, Eunice Eunhee; Dunlop, Maggie; Park, Gina; van der Boom, Edith H.
2015-01-01
One critical issue with cognitive diagnostic assessment (CDA) lies in its lack of research evidence that shows how diagnostic feedback from CDA is interpreted and used by young students. This mixed methods research examined how holistic diagnostic feedback (HDF) is processed by young learners with different profiles of reading skills, goal…
-
Córdoba, Marta; Rodriguez-Quiroga, Sergio Alejandro; Vega, Patricia Analía; Salinas, Valeria; Perez-Maturo, Josefina; Amartino, Hernán; Vásquez-Dusefante, Cecilia; Medina, Nancy; González-Morón, Dolores; Kauffman, Marcelo Andrés
2018-01-01
Background Diagnostic trajectories for neurogenetic disorders frequently require the use of considerable time and resources, exposing patients and families to so-called “diagnostic odysseys”. Previous studies have provided strong evidence for increased diagnostic and clinical utility of whole-exome sequencing in medical genetics. However, specific reports assessing its utility in a setting such as ours- a neurogeneticist led academic group serving in a low-income country—are rare. Objectives To assess the diagnostic yield of WES in patients suspected of having a neurogenetic condition and explore the cost-effectiveness of its implementation in a research group located in an Argentinean public hospital. Methods This is a prospective study of the clinical utility of WES in a series of 40 consecutive patients selected from a Neurogenetic Clinic of a tertiary Hospital in Argentina. We evaluated patients retrospectively for previous diagnostic trajectories. Diagnostic yield, clinical impact on management and economic diagnostic burden were evaluated. Results We demonstrated the clinical utility of Whole Exome Sequencing in our patient cohort, obtaining a diagnostic yield of 40% (95% CI, 24.8%-55.2%) among a diverse group of neurological disorders. The average age at the time of WES was 23 (range 3–70). The mean time elapsed from symptom onset to WES was 11 years (range 3–42). The mean cost of the diagnostic workup prior to WES was USD 1646 (USD 1439 to 1853), which is 60% higher than WES cost in our center. Conclusions WES for neurogenetics proved to be an effective, cost- and time-saving approach for the molecular diagnosis of this heterogeneous and complex group of patients. PMID:29389947
-
Kim, Young Seon; Chang, Jung Min; Yi, Ann; Shin, Sung Ui; Lee, Myung Eun; Kim, Won Hwa; Cho, Nariya; Moon, Woo Kyung
2017-08-01
To compare the diagnostic accuracy and efficiency in the interpretation of digital breast tomosynthesis (DBT) images using a picture archiving and communication system (PACS) and a dedicated workstation. 97 DBT images obtained for screening or diagnostic purposes were stored in both a workstation and a PACS and evaluated in combination with digital mammography by three independent radiologists retrospectively. Breast Imaging-Reporting and Data System final assessments and likelihood of malignancy (%) were assigned and the interpretation time when using the workstation and PACS was recorded. Receiver operating characteristic curve analysis, sensitivities and specificities were compared with histopathological examination and follow-up data as a reference standard. Area under the receiver operating characteristic curve values for cancer detection (0.839 vs 0.815, p = 0.6375) and sensitivity (81.8% vs 75.8%, p = 0.2188) showed no statistically significant differences between the workstation and PACS. However, specificity was significantly higher when analysing on the workstation than when using PACS (83.7% vs 76.9%, p = 0.009). When evaluating DBT images using PACS, only one case was deemed necessary to be reanalysed using the workstation. The mean time to interpret DBT images on PACS (1.68 min/case) was significantly longer than that to interpret on the workstation (1.35 min/case) (p < 0.0001). Interpretation of DBT images using PACS showed comparable diagnostic performance to a dedicated workstation, even though it required a longer reading time. Advances in knowledge: Interpretation of DBT images using PACS is an alternative to evaluate the images when a dedicated workstation is not available.
-
Coetzer, Andre; Sabeta, Claude T.; Markotter, Wanda; Rupprecht, Charles E.; Nel, Louis H.
2014-01-01
The major etiological agent of rabies, rabies virus (RABV), accounts for tens of thousands of human deaths per annum. The majority of these deaths are associated with rabies cycles in dogs in resource-limited countries of Africa and Asia. Although routine rabies diagnosis plays an integral role in disease surveillance and management, the application of the currently recommended direct fluorescent antibody (DFA) test in countries on the African and Asian continents remains quite limited. A novel diagnostic assay, the direct rapid immunohistochemical test (dRIT), has been reported to have a diagnostic sensitivity and specificity equal to that of the DFA test while offering advantages in cost, time and interpretation. Prior studies used the dRIT utilized monoclonal antibody (MAb) cocktails. The objective of this study was to test the hypothesis that a biotinylated polyclonal antibody (PAb) preparation, applied in the dRIT protocol, would yield equal or improved results compared to the use of dRIT with MAbs. We also wanted to compare the PAb dRIT with the DFA test, utilizing the same PAb preparation with a fluorescent label. The PAb dRIT had a diagnostic sensitivity and specificity of 100%, which was shown to be marginally higher than the diagnostic efficacy observed for the PAb DFA test. The classical dRIT, relying on two-biotinylated MAbs, was applied to the same panel of samples and a reduced diagnostic sensitivity (83.50% and 90.78% respectively) was observed. Antigenic typing of the false negative samples indicated all of these to be mongoose RABV variants. Our results provided evidence that a dRIT with alternative antibody preparations, conjugated to a biotin moiety, has a diagnostic efficacy equal to that of a DFA relying on the same antibody and that the antibody preparation should be optimized for virus variants specific to the geographical area of focus. PMID:25254652
-
Coetzer, Andre; Sabeta, Claude T; Markotter, Wanda; Rupprecht, Charles E; Nel, Louis H
2014-09-01
The major etiological agent of rabies, rabies virus (RABV), accounts for tens of thousands of human deaths per annum. The majority of these deaths are associated with rabies cycles in dogs in resource-limited countries of Africa and Asia. Although routine rabies diagnosis plays an integral role in disease surveillance and management, the application of the currently recommended direct fluorescent antibody (DFA) test in countries on the African and Asian continents remains quite limited. A novel diagnostic assay, the direct rapid immunohistochemical test (dRIT), has been reported to have a diagnostic sensitivity and specificity equal to that of the DFA test while offering advantages in cost, time and interpretation. Prior studies used the dRIT utilized monoclonal antibody (MAb) cocktails. The objective of this study was to test the hypothesis that a biotinylated polyclonal antibody (PAb) preparation, applied in the dRIT protocol, would yield equal or improved results compared to the use of dRIT with MAbs. We also wanted to compare the PAb dRIT with the DFA test, utilizing the same PAb preparation with a fluorescent label. The PAb dRIT had a diagnostic sensitivity and specificity of 100%, which was shown to be marginally higher than the diagnostic efficacy observed for the PAb DFA test. The classical dRIT, relying on two-biotinylated MAbs, was applied to the same panel of samples and a reduced diagnostic sensitivity (83.50% and 90.78% respectively) was observed. Antigenic typing of the false negative samples indicated all of these to be mongoose RABV variants. Our results provided evidence that a dRIT with alternative antibody preparations, conjugated to a biotin moiety, has a diagnostic efficacy equal to that of a DFA relying on the same antibody and that the antibody preparation should be optimized for virus variants specific to the geographical area of focus.
-
ERIC Educational Resources Information Center
Seaton, Vaughn A.
1980-01-01
The veterinary diagnostic laboratory's prime role has been diagnosis and/or laboratory findings to assist a diagnosis. Interpretation and evaluation and more involvement with decision-making in monitoring groups of animals and their health status are seen as future roles for diagnostic laboratories. (MLW)
-
Optimisation of the digital radiographic imaging of suspected non-accidental injury
NASA Astrophysics Data System (ADS)
Offiah, Amaka
Aim: To optimise the digital (radiographic) imaging of children presenting with suspected non-accidental injury (NAI). Objectives: (i) To evaluate existing radiographic quality criteria, and to develop a more suitable system if these are found to be inapplicable to skeletal surveys obtained in suspected NAI. (ii) To document differences in image quality between conventional film-screen and the recently installed Fuji5000R computed radiography (CR) system at Great Ormond Street Hospital for Children, (iii) To document the extent of variability in the standard of skeletal surveys obtained in the UK for suspected NAI. (iv) To determine those radiographic parameters which yield the highest diagnostic accuracy, while still maintaining acceptable radiation dose to the child, (v) To determine how varying degrees of edge-enhancement affect diagnostic accuracy. (vi) To establish the accuracy of soft compared to hard copy interpretation of images in suspected NAI. Materials and Methods: (i) and (ii) Retrospective analysis of 286 paediatric lateral spine radiographs by two observers based on the Commission of European Communities (CEC) quality criteria, (iii) Review of the skeletal surveys of 50 consecutive infants referred from hospitals throughout the United Kingdom (UK) with suspected NAI. (iv) Phantom studies. Leeds TO. 10 and TO. 16 test objects were used to compare the relationship between film density, exposure parameters and visualisation of object details, (iv) Clinical study. Anteroposterior and lateral post mortem skull radiographs of six consecutive infants were obtained at various exposures. Six observers independently scored the images based on visualisation of five criteria, (v) and (vi) A study of diagnostic accuracy in which six observers independently interpreted 50 radiographs from printed copies (with varying degrees of edge-enhancement) and from a monitor. Results: The CEC criteria are useful for optimisation of imaging parameters and allow the detection of differences in quality of film-screen and digital images. There is much variability in the quality and number of radiographs performed as part of skeletal surveys in the UK for suspected NAI. The Leeds test objects are either not sensitive enough (TO. 10) or perhaps over sensitive (TO. 16) for the purposes of this project. Furthermore, the minimum spatial resolution required for digital imaging in NAI has not been established. Therefore the objective interpretation of phantom studies is difficult. There is scope for reduction of radiation dose to children with no effect on image quality. Diagnostic accuracy (fracture detection) in suspected NAI is generally low, and is not affected by image display modality. Conclusions: The CEC quality criteria are not applicable to the assessment of clinical image quality. A national protocol for skeletal surveys in NAI is required. Dedicated training, close supervision, collaboration and consistent exposure of radiologists to cases of NAI should improve diagnostic accuracy. The potential exists for dose reduction when performing skeletal surveys in children and infants with suspected NAI. Future studies should address this issue.
-
Watching diagnoses develop: Eye movements reveal symptom processing during diagnostic reasoning.
Scholz, Agnes; Krems, Josef F; Jahn, Georg
2017-10-01
Finding a probable explanation for observed symptoms is a highly complex task that draws on information retrieval from memory. Recent research suggests that observed symptoms are interpreted in a way that maximizes coherence for a single likely explanation. This becomes particularly clear if symptom sequences support more than one explanation. However, there are no existing process data available that allow coherence maximization to be traced in ambiguous diagnostic situations, where critical information has to be retrieved from memory. In this experiment, we applied memory indexing, an eye-tracking method that affords rich time-course information concerning memory-based cognitive processing during higher order thinking, to reveal symptom processing and the preferred interpretation of symptom sequences. Participants first learned information about causes and symptoms presented in spatial frames. Gaze allocation to emptied spatial frames during symptom processing and during the diagnostic response reflected the subjective status of hypotheses held in memory and the preferred interpretation of ambiguous symptoms. Memory indexing traced how the diagnostic decision developed and revealed instances of hypothesis change and biases in symptom processing. Memory indexing thus provided direct online evidence for coherence maximization in processing ambiguous information.
-
Casey, D T; Frenje, J A; Gatu Johnson, M; Séguin, F H; Li, C K; Petrasso, R D; Glebov, V Yu; Katz, J; Knauer, J P; Meyerhofer, D D; Sangster, T C; Bionta, R M; Bleuel, D L; Döppner, T; Glenzer, S; Hartouni, E; Hatchett, S P; Le Pape, S; Ma, T; MacKinnon, A; McKernan, M A; Moran, M; Moses, E; Park, H-S; Ralph, J; Remington, B A; Smalyuk, V; Yeamans, C B; Kline, J; Kyrala, G; Chandler, G A; Leeper, R J; Ruiz, C L; Cooper, G W; Nelson, A J; Fletcher, K; Kilkenny, J; Farrell, M; Jasion, D; Paguio, R
2012-10-01
A magnetic recoil spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.
-
Diagnostic concordance among pathologists interpreting breast biopsy specimens.
Elmore, Joann G; Longton, Gary M; Carney, Patricia A; Geller, Berta M; Onega, Tracy; Tosteson, Anna N A; Nelson, Heidi D; Pepe, Margaret S; Allison, Kimberly H; Schnitt, Stuart J; O'Malley, Frances P; Weaver, Donald L
2015-03-17
A breast pathology diagnosis provides the basis for clinical treatment and management decisions; however, its accuracy is inadequately understood. To quantify the magnitude of diagnostic disagreement among pathologists compared with a consensus panel reference diagnosis and to evaluate associated patient and pathologist characteristics. Study of pathologists who interpret breast biopsies in clinical practices in 8 US states. Participants independently interpreted slides between November 2011 and May 2014 from test sets of 60 breast biopsies (240 total cases, 1 slide per case), including 23 cases of invasive breast cancer, 73 ductal carcinoma in situ (DCIS), 72 with atypical hyperplasia (atypia), and 72 benign cases without atypia. Participants were blinded to the interpretations of other study pathologists and consensus panel members. Among the 3 consensus panel members, unanimous agreement of their independent diagnoses was 75%, and concordance with the consensus-derived reference diagnoses was 90.3%. The proportions of diagnoses overinterpreted and underinterpreted relative to the consensus-derived reference diagnoses were assessed. Sixty-five percent of invited, responding pathologists were eligible and consented to participate. Of these, 91% (N = 115) completed the study, providing 6900 individual case diagnoses. Compared with the consensus-derived reference diagnosis, the overall concordance rate of diagnostic interpretations of participating pathologists was 75.3% (95% CI, 73.4%-77.0%; 5194 of 6900 interpretations). Among invasive carcinoma cases (663 interpretations), 96% (95% CI, 94%-97%) were concordant, and 4% (95% CI, 3%-6%) were underinterpreted; among DCIS cases (2097 interpretations), 84% (95% CI, 82%-86%) were concordant, 3% (95% CI, 2%-4%) were overinterpreted, and 13% (95% CI, 12%-15%) were underinterpreted; among atypia cases (2070 interpretations), 48% (95% CI, 44%-52%) were concordant, 17% (95% CI, 15%-21%) were overinterpreted, and 35% (95% CI, 31%-39%) were underinterpreted; and among benign cases without atypia (2070 interpretations), 87% (95% CI, 85%-89%) were concordant and 13% (95% CI, 11%-15%) were overinterpreted. Disagreement with the reference diagnosis was statistically significantly higher among biopsies from women with higher (n = 122) vs lower (n = 118) breast density on prior mammograms (overall concordance rate, 73% [95% CI, 71%-75%] for higher vs 77% [95% CI, 75%-80%] for lower, P < .001), and among pathologists who interpreted lower weekly case volumes (P < .001) or worked in smaller practices (P = .034) or nonacademic settings (P = .007). In this study of pathologists, in which diagnostic interpretation was based on a single breast biopsy slide, overall agreement between the individual pathologists' interpretations and the expert consensus-derived reference diagnoses was 75.3%, with the highest level of concordance for invasive carcinoma and lower levels of concordance for DCIS and atypia. Further research is needed to understand the relationship of these findings with patient management.
-
Hernández-Ibáñez, C; Blazquez-Sánchez, N; Aguilar-Bernier, M; Fúnez-Liébana, R; Rivas-Ruiz, F; de Troya-Martín, M
Incisional biopsy may not always provide a correct classification of histologic subtypes of basal cell carcinoma (BCC). High-frequency ultrasound (HFUS) imaging of the skin is useful for the diagnosis and management of this tumor. The main aim of this study was to compare the diagnostic value of HFUS compared with punch biopsy for the correct classification of histologic subtypes of primary BCC. We also analyzed the influence of tumor size and histologic subtype (single subtype vs. mixed) on the diagnostic yield of HFUS and punch biopsy. Retrospective observational study of primary BCCs treated by the Dermatology Department of Hospital Costa del Sol in Marbella, Spain, between october 2013 and may 2014. Surgical excision was preceded by HFUS imaging (Dermascan C © , 20-MHz linear probe) and a punch biopsy in all cases. We compared the overall diagnostic yield and accuracy (sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) of HFUS and punch biopsy against the gold standard (excisional biopsy with serial sections) for overall and subgroup results. We studied 156 cases. The overall diagnostic yield was 73.7% for HFUS (sensitivity, 74.5%; specificity, 73%) and 79.9% for punch biopsy (sensitivity, 76%; specificity, 82%). In the subgroup analyses, HFUS had a PPV of 93.3% for superficial BCC (vs. 92% for punch biopsy). In the analysis by tumor size, HFUS achieved an overall diagnostic yield of 70.4% for tumors measuring 40mm 2 or less and 77.3% for larger tumors; the NPV was 82% in both size groups. Punch biopsy performed better in the diagnosis of small lesions (overall diagnostic yield of 86.4% for lesions ≤40mm 2 vs. 72.6% for lesions >40mm 2 ). HFUS imaging was particularly useful for ruling out infiltrating BCCs, diagnosing simple, superficial BCCs, and correctly classifying BCCs larger than 40mm 2 . Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.
-
Krummen, David E; Patel, Mitul; Nguyen, Hong; Ho, Gordon; Kazi, Dhruv S; Clopton, Paul; Holland, Marian C; Greenberg, Scott L; Feld, Gregory K; Faddis, Mitchell N; Narayan, Sanjiv M
2010-11-01
Quantitative ECG Analysis. Optimal atrial tachyarrhythmia management is facilitated by accurate electrocardiogram interpretation, yet typical atrial flutter (AFl) may present without sawtooth F-waves or RR regularity, and atrial fibrillation (AF) may be difficult to separate from atypical AFl or rapid focal atrial tachycardia (AT). We analyzed whether improved diagnostic accuracy using a validated analysis tool significantly impacts costs and patient care. We performed a prospective, blinded, multicenter study using a novel quantitative computerized algorithm to identify atrial tachyarrhythmia mechanism from the surface ECG in patients referred for electrophysiology study (EPS). In 122 consecutive patients (age 60 ± 12 years) referred for EPS, 91 sustained atrial tachyarrhythmias were studied. ECGs were also interpreted by 9 physicians from 3 specialties for comparison and to allow healthcare system modeling. Diagnostic accuracy was compared to the diagnosis at EPS. A Markov model was used to estimate the impact of improved arrhythmia diagnosis. We found 13% of typical AFl ECGs had neither sawtooth flutter waves nor RR regularity, and were misdiagnosed by the majority of clinicians (0/6 correctly diagnosed by consensus visual interpretation) but correctly by quantitative analysis in 83% (5/6, P = 0.03). AF diagnosis was also improved through use of the algorithm (92%) versus visual interpretation (primary care: 76%, P < 0.01). Economically, we found that these improvements in diagnostic accuracy resulted in an average cost-savings of $1,303 and 0.007 quality-adjusted-life-years per patient. Typical AFl and AF are frequently misdiagnosed using visual criteria. Quantitative analysis improves diagnostic accuracy and results in improved healthcare costs and patient outcomes. © 2010 Wiley Periodicals, Inc.
-
Thoracic ultrasound-assisted selection for pleural biopsy with Abrams needle.
Botana-Rial, Maribel; Leiro-Fernández, Virginia; Represas-Represas, Cristina; González-Piñeiro, Ana; Tilve-Gómez, Amara; Fernández-Villar, Alberto
2013-11-01
Closed pleural biopsy (CPB) in patients with malignant pleural effusion is less sensitive than cytology. Ultrasound-assisted CPB allows biopsies to be performed in the lower thoracic parietal pleura, where secondary spread from pleural metastases is initially more likely to be found. We analyzed whether choosing the point of entry for CPB with thoracic ultrasound assistance influences the diagnostic yield in malignant pleural effusion. This prospective study included patients who underwent CPB performed by an experienced pulmonologist in 2008-2010 (group A) and thoracic ultrasound was used to select the biopsy site. The results were compared with a historical series of CPB performed by the same pulmonologist without the assistance of thoracic ultrasound (group B). An Abrams needle was used in all cases. We analyzed the obtaining of pleural tissue and the diagnostic yield. We included 114 CPBs from group A (23% tuberculous pleural effusion, 27% malignant pleural effusion) and 67 CPBs from group B (24% tuberculous pleural effusion, 30% malignant pleural effusion) (P = .70). Pleural tissue was obtained in 96.5% of the group A CPBs and 89.6% of the group B CPBs (P = .05). The diagnostic yields of CPB for tuberculous pleural effusion and malignant pleural effusion in group A were 89.5% and 77.4%, respectively, and 91.7% and 60%, respectively, in group B (P = .80 for tuberculous pleural effusion, and P = .18 for malignant pleural effusion). Selecting the point of entry for CPB using thoracic ultrasound increases the likelihood of obtaining pleural tissue and the diagnostic yield, but without statistical significance. We recommend ultrasound-assisted CPB to investigate pleural effusion, since the diagnostic yield of a pleural biopsy with an Abrams needle increased by > 17% in subjects with malignant pleural effusion.
-
Information theoretic quantification of diagnostic uncertainty.
Westover, M Brandon; Eiseman, Nathaniel A; Cash, Sydney S; Bianchi, Matt T
2012-01-01
Diagnostic test interpretation remains a challenge in clinical practice. Most physicians receive training in the use of Bayes' rule, which specifies how the sensitivity and specificity of a test for a given disease combine with the pre-test probability to quantify the change in disease probability incurred by a new test result. However, multiple studies demonstrate physicians' deficiencies in probabilistic reasoning, especially with unexpected test results. Information theory, a branch of probability theory dealing explicitly with the quantification of uncertainty, has been proposed as an alternative framework for diagnostic test interpretation, but is even less familiar to physicians. We have previously addressed one key challenge in the practical application of Bayes theorem: the handling of uncertainty in the critical first step of estimating the pre-test probability of disease. This essay aims to present the essential concepts of information theory to physicians in an accessible manner, and to extend previous work regarding uncertainty in pre-test probability estimation by placing this type of uncertainty within a principled information theoretic framework. We address several obstacles hindering physicians' application of information theoretic concepts to diagnostic test interpretation. These include issues of terminology (mathematical meanings of certain information theoretic terms differ from clinical or common parlance) as well as the underlying mathematical assumptions. Finally, we illustrate how, in information theoretic terms, one can understand the effect on diagnostic uncertainty of considering ranges instead of simple point estimates of pre-test probability.
-
Hailey, James R; Maleeff, Beverly E; Thomas, Heath C; Pearse, Gail; Klapwijk, Jan C; Cristofori, Patrizia G; Berridge, Brian; Kimbrough, Carie L; Parker, George A; Morton, Daniel; Elmore, Susan; Hardisty, Jerry F; Dybdal, Noel O; Rehagen, David A; Fikes, James D; Lamb, Martin; Biddle, Kathleen; Buetow, Bernard S; Carreira, Vinicius; Nyska, Abraham; Tripathi, Niraj K; Workman, Heather C; Bienvenu, Jean-Guy; Brees, Ingrid; Turk, James R; Adler, Rick R
2017-12-01
Spontaneous rodent progressive cardiomyopathy (PCM) in the Sprague Dawley rat may confound identification and/or interpretation of potential test article (TA)-related cardiotoxicity. Pathologists apply diagnostic term(s) and thresholds for diagnosing and assigning severity grades for PCM and/or PCM-like (PCM/like) lesions consistently within a study, which is necessary to identify and interpret TA-related findings. Due to differences in training and/or experiences, diagnostic terms and thresholds may vary between pathologists. Harmonized terminology and thresholds across studies will generate better historical control data, will likely enhance interpretation of study data, and may further enhance our understanding of the spontaneous change. An assessment of the diagnostic approaches of a group of 37 pathologists identified an approach that is relatively easily applied; and if adopted, it could enhance diagnostic consistency across studies. This approach uses the single "slash" term "necrosis/inflammatory cell infiltrate (NICI)" as the diagnosis for the spectrum of lesions seen in younger rats, uses no threshold for diagnosis (e.g., diagnose all lesions clearly identifiable as PCM/like), and uses aggregate lesion size of approximately ≥45% of the field of view (FOV) using a 10×/22 eyepiece and the 40× objective or approximately ≥100% of the FOV using the 60× objective as the criterion separating minimal from mild severities.
-
Arend, Carlos Frederico; Arend, Ana Amalia; da Silva, Tiago Rodrigues
2014-06-01
The aim of our study was to systematically compare different methodologies to establish an evidence-based approach based on tendon thickness and structure for sonographic diagnosis of supraspinatus tendinopathy when compared to MRI. US was obtained from 164 symptomatic patients with supraspinatus tendinopathy detected at MRI and 42 asymptomatic controls with normal MRI. Diagnostic yield was calculated for either maximal supraspinatus tendon thickness (MSTT) and tendon structure as isolated criteria and using different combinations of parallel and sequential testing at US. Chi-squared tests were performed to assess sensitivity, specificity, and accuracy of different diagnostic approaches. Mean MSTT was 6.68 mm in symptomatic patients and 5.61 mm in asymptomatic controls (P<.05). When used as an isolated criterion, MSTT>6.0mm provided best results for accuracy (93.7%) when compared to other measurements of tendon thickness. Also as an isolated criterion, abnormal tendon structure (ATS) yielded 93.2% accuracy for diagnosis. The best overall yield was obtained by both parallel and sequential testing using either MSTT>6.0mm or ATS as diagnostic criteria at no particular order, which provided 99.0% accuracy, 100% sensitivity, and 95.2% specificity. Among these parallel and sequential tests that provided best overall yield, additional analysis revealed that sequential testing first evaluating tendon structure required assessment of 258 criteria (vs. 261 for sequential testing first evaluating tendon thickness and 412 for parallel testing) and demanded a mean of 16.1s to assess diagnostic criteria and reach the diagnosis (vs. 43.3s for sequential testing first evaluating tendon thickness and 47.4s for parallel testing). We found that using either MSTT>6.0mm or ATS as diagnostic criteria for both parallel and sequential testing provides the best overall yield for sonographic diagnosis of supraspinatus tendinopathy when compared to MRI. Among these strategies, a two-step sequential approach first assessing tendon structure was advantageous because it required a lower number of criteria to be assessed and demanded less time to assess diagnostic criteria and reach the diagnosis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
-
Jiang, Yulei; Inciardi, Marc F; Edwards, Alexandra V; Papaioannou, John
2018-05-24
The purpose of this study was to compare diagnostic accuracy and interpretation time of screening automated breast ultrasound (ABUS) for women with dense breast tissue without and with use of a recently U.S. Food and Drug Administration-approved computer-aided detection (CAD) system for concurrent read. In a retrospective observer performance study, 18 radiologists interpreted a cancer-enriched set (i.e., cancer prevalence higher than in the original screening cohort) of 185 screening ABUS studies (52 with and 133 without breast cancer). These studies were from a large cohort of ABUS screened patients interpreted as BI-RADS density C or D. Each reader interpreted each case twice in a counterbalanced study, once without the CAD system and once with it, separated by 4 weeks. For each case, each reader identified abnormal findings and reported BI-RADS assessment category and level of suspicion for breast cancer. Interpretation time was recorded. Level of suspicion data were compared to evaluate diagnostic accuracy by means of the Dorfman-Berbaum-Metz method of jackknife with ANOVA ROC analysis. Interpretation times were compared by ANOVA. The ROC AUC was 0.848 with the CAD system, compared with 0.828 without it, for a difference of 0.020 (95% CI, -0.011 to 0.051) and was statistically noninferior to the AUC without the CAD system with respect to a margin of -0.05 (p = 0.000086). The mean interpretation time was 3 minutes 33 seconds per case without the CAD system and 2 minutes 24 seconds with it, for a difference of 1 minute 9 seconds saved (95% CI, 44-93 seconds; p = 0.000014), or a reduction in interpretation time to 67% of the time without the CAD system. Use of the concurrent-read CAD system for interpretation of screening ABUS studies of women with dense breast tissue who do not have symptoms is expected to make interpretation significantly faster and produce noninferior diagnostic accuracy compared with interpretation without the CAD system.
-
Second Preliminary Report on X-ray Yields from OMEGA II Targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fournier, K B; May, M J; MacLaren, S A
2006-08-28
We present details about X-ray yields measured with LLNL and SNL diagnostics in soft and moderately hard X-ray bands from laser-driven, doped-aerogel targets shot on 07/14/06 during the OMEGA II test series. Yields accurate to {+-}25% in the 5-15 keV band are measured with Livermore's HENWAY spectrometer. Yields in the sub-keV to 3.2 keV band are measured with LLNL's DANTE diagnostic, the DANTE yields may be 35-40% too large. SNL ran a PCD-based diagnostic that also measured X-ray yields in the spectral region above 4 keV, and also down to the nearly sub-keV range. The PCD and HENWAY and DANTEmore » numbers are compared. The time histories of the X-ray signals are measured with LLNL's H11 PCD, and from two SNL PCDs with comparable filtering. There is a persistent disagreement between the H11 PCD and SNL PCD measured FWHM, which is shown not to be due to analysis techniques. The recommended X-ray waveform is that from the SNL PCD p66k10, which was recorded on a fast, high-bandwidth TDS 6804 oscilloscope, and which are not plotted here.« less
-
A Proposed Programming System for Knuth's Mix Computer.
ERIC Educational Resources Information Center
Akers, Max Neil
A programing system using a hypothetical computer is proposed for use in teaching machine and assembly language programing courses. Major components such as monitor, assembler, interpreter, grader, and diagnostics are described. The interpreter is programed and documented for use on an IBM 360/67 computer. The interpreter can be used for teaching…
-
Body weight lower limits of fetal postmortem MRI at 1.5 T.
Jawad, N; Sebire, N J; Wade, A; Taylor, A M; Chitty, L S; Arthurs, O J
2016-07-01
To evaluate the diagnostic yield of postmortem magnetic resonance imaging (PM-MRI) compared with conventional autopsy in fetuses of early gestational age and low body weight. Fetuses of < 31 weeks' gestation that underwent 1.5-T PM-MRI and conventional autopsy were included. The findings of PM-MRI and conventional autopsy were reported blinded to each other. The reports of conventional autopsy and PM-MRI for each organ system (cardiovascular, neurological, abdominal, non-cardiac thoracic and musculoskeletal) were classified as either diagnostic or non-diagnostic. The likelihood of a non-diagnostic examination by PM-MRI was calculated according to fetal gestational age and body weight. Full datasets were examined of 204 fetuses, with mean gestational age of 20.95 ± 3.82 weeks (range, 12.0-30.7 weeks) and body-weight range of 15.9-1872 g. Body weight was the most significant predictor of diagnostic yield of PM-MRI. There was 95% confidence that 90% of fetuses will show diagnostic images by PM-MRI for all five organ systems when fetal body weight is ≥ 535 g, but < 50% of fetuses will have all five systems diagnostic on PM-MRI when body weight is < 122 g. PM-MRI is highly likely to provide adequate diagnostic images for fetuses with a body weight > 500 g. Below this weight, the diagnostic yield of standard 1.5-T PM-MRI decreases significantly. These data should help inform parents and clinicians on the suitability of performing PM-MRI in fetuses with low body weight. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
-
Martens, Leon; Goode, Grahame; Wold, Johan F H; Beck, Lionel; Martin, Georgina; Perings, Christian; Stolt, Pelle; Baggerman, Lucas
2014-01-01
To conduct a pilot study on the potential to optimise care pathways in syncope/Transient Loss of Consciousness management by using Lean Six Sigma methodology while maintaining compliance with ESC and/or NICE guidelines. Five hospitals in four European countries took part. The Lean Six Sigma methodology consisted of 3 phases: 1) Assessment phase, in which baseline performance was mapped in each centre, processes were evaluated and a new operational model was developed with an improvement plan that included best practices and change management; 2) Improvement phase, in which optimisation pathways and standardised best practice tools and forms were developed and implemented. Staff were trained on new processes and change-management support provided; 3) Sustaining phase, which included support, refinement of tools and metrics. The impact of the implementation of new pathways was evaluated on number of tests performed, diagnostic yield, time to diagnosis and compliance with guidelines. One hospital with focus on geriatric populations was analysed separately from the other four. With the new pathways, there was a 59% reduction in the average time to diagnosis (p = 0.048) and a 75% increase in diagnostic yield (p = 0.007). There was a marked reduction in repetitions of diagnostic tests and improved prioritisation of indicated tests. Applying a structured Lean Six Sigma based methodology to pathways for syncope management has the potential to improve time to diagnosis and diagnostic yield.
-
Martens, Leon; Goode, Grahame; Wold, Johan F. H.; Beck, Lionel; Martin, Georgina; Perings, Christian; Stolt, Pelle; Baggerman, Lucas
2014-01-01
Aims To conduct a pilot study on the potential to optimise care pathways in syncope/Transient Loss of Consciousness management by using Lean Six Sigma methodology while maintaining compliance with ESC and/or NICE guidelines. Methods Five hospitals in four European countries took part. The Lean Six Sigma methodology consisted of 3 phases: 1) Assessment phase, in which baseline performance was mapped in each centre, processes were evaluated and a new operational model was developed with an improvement plan that included best practices and change management; 2) Improvement phase, in which optimisation pathways and standardised best practice tools and forms were developed and implemented. Staff were trained on new processes and change-management support provided; 3) Sustaining phase, which included support, refinement of tools and metrics. The impact of the implementation of new pathways was evaluated on number of tests performed, diagnostic yield, time to diagnosis and compliance with guidelines. One hospital with focus on geriatric populations was analysed separately from the other four. Results With the new pathways, there was a 59% reduction in the average time to diagnosis (p = 0.048) and a 75% increase in diagnostic yield (p = 0.007). There was a marked reduction in repetitions of diagnostic tests and improved prioritisation of indicated tests. Conclusions Applying a structured Lean Six Sigma based methodology to pathways for syncope management has the potential to improve time to diagnosis and diagnostic yield. PMID:24927475
-
Mutation in an alternative transcript of CDKL5 in a boy with early-onset seizures.
Bodian, Dale L; Schreiber, John M; Vilboux, Thierry; Khromykh, Alina; Hauser, Natalie S
2018-06-01
Infantile-onset epilepsies are a set of severe, heterogeneous disorders for which clinical genetic testing yields causative mutations in ∼20%-50% of affected individuals. We report the case of a boy presenting with intractable seizures at 2 wk of age, for whom gene panel testing was unrevealing. Research-based whole-genome sequencing of the proband and four unaffected family members identified a de novo mutation, NM_001323289.1:c.2828_2829delGA in CDKL5, a gene associated with X-linked early infantile epileptic encephalopathy 2. CDKL5 has multiple alternative transcripts, and the mutation lies in an exon in the brain-expressed forms. The mutation was undetected by gene panel sequencing because of its intronic location in the CDKL5 transcript typically used to define the exons of this gene for clinical exon-based tests (NM_003159). This is the first report of a patient with a mutation in an alternative transcript of CDKL5 This finding suggests that incorporating alternative transcripts into the design and variant interpretation of exon-based tests, including gene panel and exome sequencing, could improve the diagnostic yield. © 2018 Bodian et al.; Published by Cold Spring Harbor Laboratory Press.
-
Mutation in an alternative transcript of CDKL5 in a boy with early-onset seizures
Bodian, Dale L.; Schreiber, John M.; Vilboux, Thierry; Khromykh, Alina; Hauser, Natalie S.
2018-01-01
Infantile-onset epilepsies are a set of severe, heterogeneous disorders for which clinical genetic testing yields causative mutations in ∼20%–50% of affected individuals. We report the case of a boy presenting with intractable seizures at 2 wk of age, for whom gene panel testing was unrevealing. Research-based whole-genome sequencing of the proband and four unaffected family members identified a de novo mutation, NM_001323289.1:c.2828_2829delGA in CDKL5, a gene associated with X-linked early infantile epileptic encephalopathy 2. CDKL5 has multiple alternative transcripts, and the mutation lies in an exon in the brain-expressed forms. The mutation was undetected by gene panel sequencing because of its intronic location in the CDKL5 transcript typically used to define the exons of this gene for clinical exon-based tests (NM_003159). This is the first report of a patient with a mutation in an alternative transcript of CDKL5. This finding suggests that incorporating alternative transcripts into the design and variant interpretation of exon-based tests, including gene panel and exome sequencing, could improve the diagnostic yield. PMID:29444904
-
Photoionization Modeling and the K Lines of Iron
NASA Technical Reports Server (NTRS)
Kallman, T. R.; Palmeri, P.; Bautista, M. A.; Mendoza, C.; Krolik, J. H.
2004-01-01
We calculate the efficiency of iron K line emission and iron K absorption in photoionized models using a new set of atomic data. These data are more comprehensive than those previously applied to the modeling of iron K lines from photoionized gases, and allow us to systematically examine the behavior of the properties of line emission and absorption as a function of the ionization parameter, density and column density of model constant density clouds. We show that, for example, the net fluorescence yield for the highly charged ions is sensitive to the level population distribution produced by photoionization, and these yields are generally smaller than those predicted assuming the population is according to statistical weight. We demonstrate that the effects of the many strongly damped resonances below the K ionization thresholds conspire to smear the edge, thereby potentially affecting the astrophysical interpretation of absorption features in the 7-9 keV energy band. We show that the centroid of the ensemble of K(alpha) lines, the K(beta) energy, and the ratio of the K(alpha(sub 1)) to K(alpha(sub 2)) components are all diagnostics of the ionization parameter of our model slabs.
-
Michelson, D J; Shevell, M I; Sherr, E H; Moeschler, J B; Gropman, A L; Ashwal, S
2011-10-25
To systematically review the evidence concerning the diagnostic yield of genetic and metabolic evaluation of children with global developmental delay or intellectual disability (GDD/ID). Relevant literature was reviewed, abstracted, and classified according to the 4-tiered American Academy of Neurology classification of evidence scheme. In patients with GDD/ID, microarray testing is diagnostic on average in 7.8% (Class III), G-banded karyotyping is abnormal in at least 4% (Class II and III), and subtelomeric fluorescence in situ hybridization is positive in 3.5% (Class I, II, and III). Testing for X-linked ID genes has a yield of up to 42% in males with an appropriate family history (Class III). FMR1 testing shows full expansion in at least 2% of patients with mild to moderate GDD/ID (Class II and III), and MeCP2 testing is diagnostic in 1.5% of females with moderate to severe GDD/ID (Class III). Tests for metabolic disorders have a yield of up to 5%, and tests for congenital disorders of glycosylation and cerebral creatine disorders have yields of up to 2.8% (Class III). Several genetic and metabolic screening tests have been shown to have a better than 1% diagnostic yield in selected populations of children with GDD/ID. These values should be among the many factors considered in planning the laboratory evaluation of such children.
-
Critically re-evaluating a common technique: Accuracy, reliability, and confirmation bias of EMG.
Narayanaswami, Pushpa; Geisbush, Thomas; Jones, Lyell; Weiss, Michael; Mozaffar, Tahseen; Gronseth, Gary; Rutkove, Seward B
2016-01-19
(1) To assess the diagnostic accuracy of EMG in radiculopathy. (2) To evaluate the intrarater reliability and interrater reliability of EMG in radiculopathy. (3) To assess the presence of confirmation bias in EMG. Three experienced academic electromyographers interpreted 3 compact discs with 20 EMG videos (10 normal, 10 radiculopathy) in a blinded, standardized fashion without information regarding the nature of the study. The EMGs were interpreted 3 times (discs A, B, C) 1 month apart. Clinical information was provided only with disc C. Intrarater reliability was calculated by comparing interpretations in discs A and B, interrater reliability by comparing interpretation between reviewers. Confirmation bias was estimated by the difference in correct interpretations when clinical information was provided. Sensitivity was similar to previous reports (77%, confidence interval [CI] 63%-90%); specificity was 71%, CI 56%-85%. Intrarater reliability was good (κ 0.61, 95% CI 0.41-0.81); interrater reliability was lower (κ 0.53, CI 0.35-0.71). There was no substantial confirmation bias when clinical information was provided (absolute difference in correct responses 2.2%, CI -13.3% to 17.7%); the study lacked precision to exclude moderate confirmation bias. This study supports that (1) serial EMG studies should be performed by the same electromyographer since intrarater reliability is better than interrater reliability; (2) knowledge of clinical information does not bias EMG interpretation substantially; (3) EMG has moderate diagnostic accuracy for radiculopathy with modest specificity and electromyographers should exercise caution interpreting mild abnormalities. This study provides Class III evidence that EMG has moderate diagnostic accuracy and specificity for radiculopathy. © 2015 American Academy of Neurology.
-
Critically re-evaluating a common technique
Geisbush, Thomas; Jones, Lyell; Weiss, Michael; Mozaffar, Tahseen; Gronseth, Gary; Rutkove, Seward B.
2016-01-01
Objectives: (1) To assess the diagnostic accuracy of EMG in radiculopathy. (2) To evaluate the intrarater reliability and interrater reliability of EMG in radiculopathy. (3) To assess the presence of confirmation bias in EMG. Methods: Three experienced academic electromyographers interpreted 3 compact discs with 20 EMG videos (10 normal, 10 radiculopathy) in a blinded, standardized fashion without information regarding the nature of the study. The EMGs were interpreted 3 times (discs A, B, C) 1 month apart. Clinical information was provided only with disc C. Intrarater reliability was calculated by comparing interpretations in discs A and B, interrater reliability by comparing interpretation between reviewers. Confirmation bias was estimated by the difference in correct interpretations when clinical information was provided. Results: Sensitivity was similar to previous reports (77%, confidence interval [CI] 63%–90%); specificity was 71%, CI 56%–85%. Intrarater reliability was good (κ 0.61, 95% CI 0.41–0.81); interrater reliability was lower (κ 0.53, CI 0.35–0.71). There was no substantial confirmation bias when clinical information was provided (absolute difference in correct responses 2.2%, CI −13.3% to 17.7%); the study lacked precision to exclude moderate confirmation bias. Conclusions: This study supports that (1) serial EMG studies should be performed by the same electromyographer since intrarater reliability is better than interrater reliability; (2) knowledge of clinical information does not bias EMG interpretation substantially; (3) EMG has moderate diagnostic accuracy for radiculopathy with modest specificity and electromyographers should exercise caution interpreting mild abnormalities. Classification of evidence: This study provides Class III evidence that EMG has moderate diagnostic accuracy and specificity for radiculopathy. PMID:26701380
-
Evolutionary fuzzy modeling human diagnostic decisions.
Peña-Reyes, Carlos Andrés
2004-05-01
Fuzzy CoCo is a methodology, combining fuzzy logic and evolutionary computation, for constructing systems able to accurately predict the outcome of a human decision-making process, while providing an understandable explanation of the underlying reasoning. Fuzzy logic provides a formal framework for constructing systems exhibiting both good numeric performance (accuracy) and linguistic representation (interpretability). However, fuzzy modeling--meaning the construction of fuzzy systems--is an arduous task, demanding the identification of many parameters. To solve it, we use evolutionary computation techniques (specifically cooperative coevolution), which are widely used to search for adequate solutions in complex spaces. We have successfully applied the algorithm to model the decision processes involved in two breast cancer diagnostic problems, the WBCD problem and the Catalonia mammography interpretation problem, obtaining systems both of high performance and high interpretability. For the Catalonia problem, an evolved system was embedded within a Web-based tool-called COBRA-for aiding radiologists in mammography interpretation.
-
THE EFFECT OF ADVANCE IN LACTATION AND GESTATION ON MAMMARY ACTIVITY.
Gaines, W L; Davidson, F A
1926-01-20
The rate of milk secretion in farrow cows may be expressed as See PDF for Equation, in which y = yield and t = time from calving. Pregnancy causes a decrease in yield which may be expressed as See PDF for Equation, in which i = inhibition or decrease in yield and p = time from conception. The constant K appears to be the same for various groups but b is roughly proportional to a. The decrease in yield associated with pregnancy is interpreted as due to a hormone. The hormone hypothesis also affords an interpretation of the increasing rate of milk secretion which occurs for a short time following parturition.
-
Ko, Yousang; Song, Jinkyung; Lee, Suh-Young; Moon, Jin-Wook; Mo, Eun-Kyung; Park, Ji Young; Kim, Joo-Hee; Park, Sunghoon; Hwang, Yong Il; Jang, Seung Hun; Jhun, Byung Woo; Sim, Yun Su; Shin, Tae Rim; Kim, Dong-Gyu; Hong, Ji Young; Lee, Chang Youl; Lee, Myung Goo; Kim, Cheol-Hong; Hyun, In Gyu; Park, Yong Bum
2017-01-01
Despite recent advances in methods for culturing Mycobacterium tuberculosis (MTB), the diagnostic yield of tuberculous pleural effusion (TBPE) remains unsatisfactory. However, unlike repeated sputum cultures of pulmonary tuberculosis, little is known about the role of repeated pleural cultures. We examined whether repeated pleural cultures are associated with increased MTB yield from TBPE. A multicenter, retrospective cohort study was performed from January 2012 to December 2015 in South Korea. Patients were categorized into two groups: single- or repeated-culture groups. The diagnostic yield of MTB and clinical, radiological, and pleural fluid characteristics were evaluated. Among the 329 patients with TBPE, 77 (23.4%) had repeated cultures and 252 (76.5%) had a single culture. Pleural culture was performed twice in all 77 patients in the repeated-culture group at a 1-day interval (inter-quartile range, 1.0-2.0). In the repeated-culture group, the yield of MTB from the first culture was 31.2%, which was similar to that in the single-culture group (31.2% vs. 29.8%, P = 0.887). However, the yield of MTB from the second culture (10/77, 13.0%) was more than that from the first. These results may be attributable to the insufficient immune clearance for MTB invasion into the pleural space between the first and second cultures. Over time, the yield of the second cultures decreased from 17.4% to 6.7% and then 6.3%. Finally, the overall yield of MTB in the repeated- and single-culture groups was 44.2% and 29.8% respectively (P < 0.001). The results showed that repeated pleural cultures increased MTB yield from TBPE in human immunodeficiency virus-negative individuals. Furthermore, repeated cultures may increase yield when carried out for two consecutive days.
-
Tam, Teck Lip Dexter; Lin, Ting Ting; Chua, Ming Hui
2017-06-21
Here we utilized new diagnostic tools in time-dependent density functional theory to explain the trend of intersystem crossing in benzo(bis)-X-diazole based donor-acceptor-donor type molecules. These molecules display a wide range of fluorescence quantum yields and triplet yields, making them excellent candidates for testing the validity of these diagnostic tools. We believe that these tools are cost-effective and can be applied to structurally similar organic chromophores to predict/explain the trends of intersystem crossing, and thus fluorescence quantum yields and triplet yields without the use of complex and expensive multireference configuration interaction or multireference pertubation theory methods.
-
Concordance in diagnostic testing for respiratory pathogens of bighorn sheep
Walsh, Daniel P.; Cassirer, E. Frances; Bonds, Michael D.; Brown, Daniel R.; Edwards, William H.; Weiser, Glen C.; Drew, Mark L.; Briggs, Robert E.; Fox, Karen A.; Miller, Michael W.; Shanthalingam, Sudarvili; Srikumaran, Subramaniam; Besser, Thomas E.
2016-01-01
Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep (Ovis canadensis), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae, Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi(median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimiaspp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.
-
Savant, Deepika; Bajaj, Jaya; Gimenez, Cecilia; Rafael, Oana C; Mirzamani, Neda; Chau, Karen; Klein, Melissa; Das, Kasturi
2017-01-01
Urine cytology is the most frequently utilized test to detect urothelial cancer. Secondary bladder neoplasms need to be recognized as this impacts patient management. We report our experience on nonurothelial malignancies (NUM) detected in urine cytology over a 10-year period. A 10-year retrospective search for patients with biopsy-proven NUM to the urothelial tract yielded 25 urine samples from 14 patients. Two cytopathologists blinded to the original cytology diagnosis reviewed the cytology and histology slides. The incidence, cytomorphologic features, diagnostic accuracy, factors influencing the diagnostic accuracy, and clinical impact of the cytology result were studied. The incidence of NUM was <1%. The male:female ratio was 1.3. An abnormality was detected in 60% of the cases; however, in only 4% of the cases, a primary site was identified accurately. Of the false negatives, 96% was deemed as sampling errors and 4% was interpretational. Patient management was not impacted in any of the false-negative cases due to concurrent or past tissue diagnosis. Colon cancer was the most frequent secondary tumor. Sampling error attributed to the false-negative results. Necrosis and dirty background was often associated with metastatic lesions from colon. Obtaining history of a primary tumor elsewhere was a key factor in diagnosis of a metastatic lesion. Hematopoietic malignancies remain to be a diagnostic challenge. Cytospin preparations were superior for evaluating nuclear detail and background material as opposed to monolayer (Thinprep) technology. Diagnostic accuracy was improved by obtaining immunohistochemistry. Diagn. Cytopathol. 2016. © 2016 Wiley Periodicals, Inc. Diagn. Cytopathol. 2017;45:22-28. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
-
Ohashi, Ryoko; Nagao, Michinobu; Nakamura, Izumi; Okamoto, Takahiro; Sakai, Shuji
2018-04-12
The aim of this study was to determine if the diagnostic performance of breast lesion examinations could be improved using both digital breast tomosynthesis (DBT) and conventional digital mammography (CDM). Our institutional review board approved the protocol, and patients were provided the opportunity to opt out of the study. A total of 628 patients aged 22-91 years with abnormal screening results or clinical symptoms were consecutively enrolled between June 2015 and March 2016. All patients underwent DBT and CDM, and 1164 breasts were retrospectively analyzed by three radiologists who interpreted the results based on the Breast Imaging Reporting and Data System. Categories 4 and 5 were considered positive, and pathological results were the gold standard. The diagnostic performance of CDM and CDM plus DBT was compared using the mean areas under the receiver operating characteristic (ROC) curves. A total of 100 breast cancer cases were identified. The areas under the ROC curves were 0.9160 (95% confidence interval 0.8779-0.9541) for CDM alone and 0.9376 (95% confidence interval 0.9019-0.9733) for CDM plus DBT. The cut-off values for both CDM alone and CDM plus DBT measurements were 4, with sensitivities of 61.0% (61/100) and 83.0% (83/100), respectively, and specificities of 99.1% (1054/1064) and 98.9% (1052/1064), respectively. CDM yielded 39 false-negative diagnoses, while CDM plus DBT identified breast cancer in 22 of those cases (56.4%). The combination of DBT and CDM for the diagnosis of breast cancer in women with abnormal examination findings or clinical symptoms proved effective and should be used to improve the diagnostic performance of breast cancer examinations.
-
ERIC Educational Resources Information Center
Gierl, Mark J.; Cui, Ying
2008-01-01
One promising application of diagnostic classification models (DCM) is in the area of cognitive diagnostic assessment in education. However, the successful application of DCM in educational testing will likely come with a price--and this price may be in the form of new test development procedures and practices required to yield data that satisfy…
-
North, Carol S; Pfefferbaum, Betty; Tucker, Phebe
2002-08-01
Empirical data from research studies are vital to guiding mental health interventions following disasters. However, few data are available for this purpose. Important advances in policy and procedures for the conduct of organized research emerged from the Oklahoma City bombing, yielding cooperative working relationships among researchers and culminating in the ethical attainment of informative research data. However, the academic community was again caught off guard after the September 11, 2001, terrorist attacks. Suggestions to surmount these obstacles include incorporating research infrastructures into disaster preparedness plans in advance; organizing the community of researchers; and working closely with major funding organizations. Methodological issues pertaining to measurement of psychopathology include the importance of obtaining diagnostic data; interpreting the meaning of symptoms in the absence of a psychiatric disorder; differentiating preexisting symptoms from those that emerged after the disaster, and optimal timing of postdisaster assessment.
-
Clinical application of next-generation sequencing for Mendelian diseases.
Jamuar, Saumya Shekhar; Tan, Ene-Choo
2015-06-16
Over the past decade, next-generation sequencing (NGS) has led to an exponential increase in our understanding of the genetic basis of Mendelian diseases. NGS allows for the analysis of multiple regions of the genome in one single reaction and has been shown to be a cost-effective and efficient tool in investigating patients with Mendelian diseases. More recently, NGS has been successfully deployed in the clinics, with a reported diagnostic yield of ~25 %. However, recommendations on clinical implementation of NGS are still evolving with numerous key challenges that impede the widespread use of genetics in everyday medicine. These challenges include when to order, on whom to order, what type of test to order, and how to interpret and communicate the results, including incidental findings, to the patient and family. In this review, we discuss these challenges and suggest guidelines on implementing NGS in the routine clinical workflow.
-
Pro and Contra: Provocation Tests in Drug Hypersensitivity
Soyer, Ozge; Sahiner, Umit Murat; Sekerel, Bulent Enis
2017-01-01
Drug provocation test (DPT) is the controlled administration of a drug to diagnose immune- or non-immune-mediated drug hypersensitivity and the last step for accurate recognition of drug hypersensitivity reactions when the previous diagnostic evaluations are negative or unavailable. A DPT is performed only if other conventional tests fail to yield conclusive results. In each clinical presentation, “to provoke or not to provoke” a patient should be decided after careful assessment of the risk–benefit ratio. Well-defined benefits of DPT include confirmative exclusion of diagnoses of drug hypersensitivity and provision of safe alternatives. However, disadvantages such as safety, difficulty in interpretations of results, lack of objective biomarkers, risks of resensitization, efficiency in daily practice, and lack of standardized protocols, are poorly debated. This review summarizes the current published research concerning DPT, with particular emphasis on the advantages and disadvantages of DPT in an evidence-based manner. PMID:28677662
-
Automatic enhancement of skin fluorescence localization due to refractive index matching
NASA Astrophysics Data System (ADS)
Churmakov, Dmitry Y.; Meglinski, Igor V.; Piletsky, Sergey A.; Greenhalgh, Douglas A.
2004-07-01
Fluorescence diagnostic techniques are notable amongst many other optical methods, as they offer high sensitivity and non-invasive measurements of tissue properties. However, a combination of multiple scattering and physical heterogeneity of biological tissues hampers the interpretation of the fluorescence measurements. The analyses of the spatial distribution of endogenous and exogenous fluorophores excitations within tissues and their contribution to the detected signal localization are essential for many applications. We have developed a novel Monte Carlo technique that gives a graphical perception of how the excitation and fluorescence detected signal are localized in tissues. Our model takes into account spatial distribution of fluorophores and their quantum yields. We demonstrate that matching of the refractive indices of ambient medium and topical skin layer improves spatial localization of the detected fluorescence signal within the tissue. This result is consistent with the recent conclusion that administering biocompatible agents results in higher image contrast.
-
Electrocardiographic interpretation skills of cardiology residents: are they competent?
Sibbald, Matthew; Davies, Edward G; Dorian, Paul; Yu, Eric H C
2014-12-01
Achieving competency at electrocardiogram (ECG) interpretation among cardiology subspecialty residents has traditionally focused on interpreting a target number of ECGs during training. However, there is little evidence to support this approach. Further, there are no data documenting the competency of ECG interpretation skills among cardiology residents, who become de facto the gold standard in their practice communities. We tested 29 Cardiology residents from all 3 years in a large training program using a set of 20 ECGs collected from a community cardiology practice over a 1-month period. Residents interpreted half of the ECGs using a standard analytic framework, and half using their own approach. Residents were scored on the number of correct and incorrect diagnoses listed. Overall diagnostic accuracy was 58%. Of 6 potentially life-threatening diagnoses, residents missed 36% (123 of 348) including hyperkalemia (81%), long QT (52%), complete heart block (35%), and ventricular tachycardia (19%). Residents provided additional inappropriate diagnoses on 238 ECGs (41%). Diagnostic accuracy was similar between ECGs interpreted using an analytic framework vs ECGs interpreted without an analytic framework (59% vs 58%; F(1,1333) = 0.26; P = 0.61). Cardiology resident proficiency at ECG interpretation is suboptimal. Despite the use of an analytic framework, there remain significant deficiencies in ECG interpretation among Cardiology residents. A more systematic method of addressing these important learning gaps is urgently needed. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
-
Code of Federal Regulations, 2011 CFR
2011-10-01
...) or professional component (PC) of a diagnostic test that was ordered by the physician or other... behalf of the beneficiary) for the TC or PC of the diagnostic test may not exceed the lowest of the... who supervised the TC, and with respect to the PC, the performing supplier is the physician who...
-
Investigating the Link Between Radiologists Gaze, Diagnostic Decision, and Image Content
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tourassi, Georgia; Voisin, Sophie; Paquit, Vincent C
2013-01-01
Objective: To investigate machine learning for linking image content, human perception, cognition, and error in the diagnostic interpretation of mammograms. Methods: Gaze data and diagnostic decisions were collected from six radiologists who reviewed 20 screening mammograms while wearing a head-mounted eye-tracker. Texture analysis was performed in mammographic regions that attracted radiologists attention and in all abnormal regions. Machine learning algorithms were investigated to develop predictive models that link: (i) image content with gaze, (ii) image content and gaze with cognition, and (iii) image content, gaze, and cognition with diagnostic error. Both group-based and individualized models were explored. Results: By poolingmore » the data from all radiologists machine learning produced highly accurate predictive models linking image content, gaze, cognition, and error. Merging radiologists gaze metrics and cognitive opinions with computer-extracted image features identified 59% of the radiologists diagnostic errors while confirming 96.2% of their correct diagnoses. The radiologists individual errors could be adequately predicted by modeling the behavior of their peers. However, personalized tuning appears to be beneficial in many cases to capture more accurately individual behavior. Conclusions: Machine learning algorithms combining image features with radiologists gaze data and diagnostic decisions can be effectively developed to recognize cognitive and perceptual errors associated with the diagnostic interpretation of mammograms.« less
-
NASA Technical Reports Server (NTRS)
Oreilly, Daniel; Williams, Robert; Yarborough, Kevin
1988-01-01
This is a tutorial/diagnostic system for training personnel in the use of the Space Shuttle Main Engine Controller (SSMEC) Simulation Lab. It also provides a diagnostic capable of isolating lab failures at least to the major lab component. The system was implemented using Hypercard, which is an program of hypermedia running on Apple Macintosh computers. Hypercard proved to be a viable platform for the development and use of sophisticated tutorial systems and moderately capable diagnostic systems. This tutorial/diagnostic system uses the basic Hypercard tools to provide the tutorial. The diagnostic part of the system uses a simple interpreter written in the Hypercard language (Hypertalk) to implement the backward chaining rule based logic commonly found in diagnostic systems using Prolog. Some of the advantages of Hypercard in developing this type of system include sophisticated graphics, animation, sound and voice capabilities, its ability as a hypermedia tool, and its ability to include digitized pictures. The major disadvantage is the slow execution time for evaluation of rules (due to the interpretive processing of the language). Other disadvantages include the limitation on the size of the cards, that color is not supported, that it does not support grey scale graphics, and its lack of selectable fonts for text fields.
-
Measures of accuracy and performance of diagnostic tests.
Drobatz, Kenneth J
2009-05-01
Diagnostic tests are integral to the practice of veterinary cardiology, any other specialty, and general veterinary medicine. Developing and understanding diagnostic tests is one of the cornerstones of clinical research. This manuscript describes the diagnostic test properties including sensitivity, specificity, predictive value, likelihood ratio, receiver operating characteristic curve. Review of practical book chapters and standard statistics manuscripts. Diagnostics such as sensitivity, specificity, predictive value, likelihood ratio, and receiver operating characteristic curve are described and illustrated. Basic understanding of how diagnostic tests are developed and interpreted is essential in reviewing clinical scientific papers and understanding evidence based medicine.
-
Salazar, Antonio J; Useche, Nicolás; Granja, Manuel; Morillo, Aníbal J; Bermúdez, Sonia
2017-01-01
The aim of this study was to evaluate the equivalence of brain CT interpretations performed using a diagnostic workstation and a mobile tablet computer, in a telestroke service. The ethics committee of our institution approved this retrospective study. A factorial design with 1452 interpretations was used. The assessed variables were the type of stroke classification, the presence of contraindications to the tPA administration, the presence of a hyperdense intracranial artery sign (HMCA), and the Alberta Stroke Program Early CT Score (ASPECTS) score. These variables were evaluated to determine the effect that the reading system had on their magnitudes. The achieved distribution of observed lesions using both the reading systems was not statistically different. The differences between the two reading systems to claim equivalence were 1.6% for hemorrhagic lesions, 4.5% for cases without lesion, and 5.2 for overall ischemic lesion. Equivalence was achieved at 2.1% for ASPECTS ≤ 6, 6.5% for the presence of imaging contraindication to the tPA administration, and 7.2% for the presence of HMCA. The diagnostic performance for detecting acute stroke is likely equivalent whether a tablet computer or a diagnostic workstation is used or not.
-
Trotz-Williams, L A; Mercer, N J; Paphitis, K; Walters, J M; Wallace, D; Kristjanson, E; Gubbay, J; Mazzulli, T
2017-02-01
In spite of a greatly reduced incidence rate due to vaccination, mumps outbreaks continue to occur in several areas of the world, sometimes in vaccinated populations. This article describes an outbreak in a highly vaccinated population in southwestern Ontario, Canada, and the challenges encountered in interpreting the results of diagnostic tests used in the outbreak. During the outbreak, patients were interviewed and classified according to the outbreak case definition, and specimens were collected for diagnostic testing according to Ontario guidelines. Twenty-seven individuals were classified as confirmed cases (n = 19) or suspect cases (n = 8) according to the case definition, only 9 of which were laboratory-confirmed cases: 7 confirmed by reverse transcriptase PCR (RT-PCR) and 2 by IgM serology. All 19 confirmed cases represented patients who were associated with secondary schools in the local area and had been vaccinated against mumps with one (n = 2) or two (n = 17) doses of the measles-mumps-rubella (MMR) vaccine. This is the first published report of an outbreak of mumps in Ontario in which all confirmed cases had been vaccinated against the disease. It highlights the limitations of and difficulties in interpreting current mumps diagnostic tests when used in vaccinated individuals. Copyright © 2017 American Society for Microbiology.
-
Useche, Nicolás; Granja, Manuel; Morillo, Aníbal J.; Bermúdez, Sonia
2017-01-01
Objective The aim of this study was to evaluate the equivalence of brain CT interpretations performed using a diagnostic workstation and a mobile tablet computer, in a telestroke service. Materials and Methods The ethics committee of our institution approved this retrospective study. A factorial design with 1452 interpretations was used. The assessed variables were the type of stroke classification, the presence of contraindications to the tPA administration, the presence of a hyperdense intracranial artery sign (HMCA), and the Alberta Stroke Program Early CT Score (ASPECTS) score. These variables were evaluated to determine the effect that the reading system had on their magnitudes. Results The achieved distribution of observed lesions using both the reading systems was not statistically different. The differences between the two reading systems to claim equivalence were 1.6% for hemorrhagic lesions, 4.5% for cases without lesion, and 5.2 for overall ischemic lesion. Equivalence was achieved at 2.1% for ASPECTS ≤ 6, 6.5% for the presence of imaging contraindication to the tPA administration, and 7.2% for the presence of HMCA. Conclusion The diagnostic performance for detecting acute stroke is likely equivalent whether a tablet computer or a diagnostic workstation is used or not. PMID:29250111
-
Mercer, N. J.; Paphitis, K.; Walters, J. M.; Wallace, D.; Kristjanson, E.; Gubbay, J.; Mazzulli, T.
2016-01-01
ABSTRACT In spite of a greatly reduced incidence rate due to vaccination, mumps outbreaks continue to occur in several areas of the world, sometimes in vaccinated populations. This article describes an outbreak in a highly vaccinated population in southwestern Ontario, Canada, and the challenges encountered in interpreting the results of diagnostic tests used in the outbreak. During the outbreak, patients were interviewed and classified according to the outbreak case definition, and specimens were collected for diagnostic testing according to Ontario guidelines. Twenty-seven individuals were classified as confirmed cases (n = 19) or suspect cases (n = 8) according to the case definition, only 9 of which were laboratory-confirmed cases: 7 confirmed by reverse transcriptase PCR (RT-PCR) and 2 by IgM serology. All 19 confirmed cases represented patients who were associated with secondary schools in the local area and had been vaccinated against mumps with one (n = 2) or two (n = 17) doses of the measles-mumps-rubella (MMR) vaccine. This is the first published report of an outbreak of mumps in Ontario in which all confirmed cases had been vaccinated against the disease. It highlights the limitations of and difficulties in interpreting current mumps diagnostic tests when used in vaccinated individuals. PMID:28003216
-
Iftikhar, Imran H; Alghothani, Lana; Sardi, Alejandro; Berkowitz, David; Musani, Ali I
2017-07-01
Transbronchial lung cryobiopsy is increasingly being used for the assessment of diffuse parenchymal lung diseases. Several studies have shown larger biopsy samples and higher yields compared with conventional transbronchial biopsies. However, the higher risk of bleeding and other complications has raised concerns for widespread use of this modality. To study the diagnostic accuracy and safety profile of transbronchial lung cryobiopsy and compare with video-assisted thoracoscopic surgery (VATS) by reviewing available evidence from the literature. Medline and PubMed were searched from inception until December 2016. Data on diagnostic performance were abstracted by constructing two-by-two contingency tables for each study. Data on a priori selected safety outcomes were collected. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool. Random effects meta-analyses were performed to obtain summary estimates of the diagnostic accuracy. The pooled diagnostic yield, pooled sensitivity, and pooled specificity of transbronchial lung cryobiopsy were 83.7% (76.9-88.8%), 87% (85-89%), and 57% (40-73%), respectively. The pooled diagnostic yield, pooled sensitivity, and pooled specificity of VATS were 92.7% (87.6-95.8%), 91.0% (89-92%), and 58% (31-81%), respectively. The incidence of grade 2 (moderate to severe) endobronchial bleeding after transbronchial lung cryobiopsy and of post-procedural pneumothorax was 4.9% (2.2-10.7%) and 9.5% (5.9-14.9%), respectively. Although the diagnostic test accuracy measures of transbronchial lung cryobiopsy lag behind those of VATS, with an acceptable safety profile and potential cost savings, the former could be considered as an alternative in the evaluation of patients with diffuse parenchymal lung diseases.
-
Diagnostic Concordance Among Pathologists Interpreting Breast Biopsy Specimens
Elmore, Joann G.; Longton, Gary M.; Carney, Patricia A.; Geller, Berta M.; Onega, Tracy; Tosteson, Anna N. A.; Nelson, Heidi D.; Pepe, Margaret S.; Allison, Kimberly H.; Schnitt, Stuart J.; O’Malley, Frances P.; Weaver, Donald L.
2015-01-01
IMPORTANCE A breast pathology diagnosis provides the basis for clinical treatment and management decisions; however, its accuracy is inadequately understood. OBJECTIVES To quantify the magnitude of diagnostic disagreement among pathologists compared with a consensus panel reference diagnosis and to evaluate associated patient and pathologist characteristics. DESIGN, SETTING, AND PARTICIPANTS Study of pathologists who interpret breast biopsies in clinical practices in 8 US states. EXPOSURES Participants independently interpreted slides between November 2011 and May 2014 from test sets of 60 breast biopsies (240 total cases, 1 slide per case), including 23 cases of invasive breast cancer, 73 ductal carcinoma in situ (DCIS), 72 with atypical hyperplasia (atypia), and 72 benign cases without atypia. Participants were blinded to the interpretations of other study pathologists and consensus panel members. Among the 3 consensus panel members, unanimous agreement of their independent diagnoses was 75%, and concordance with the consensus-derived reference diagnoses was 90.3%. MAIN OUTCOMES AND MEASURES The proportions of diagnoses overinterpreted and underinterpreted relative to the consensus-derived reference diagnoses were assessed. RESULTS Sixty-five percent of invited, responding pathologists were eligible and consented to participate. Of these, 91% (N = 115) completed the study, providing 6900 individual case diagnoses. Compared with the consensus-derived reference diagnosis, the overall concordance rate of diagnostic interpretations of participating pathologists was 75.3% (95% CI, 73.4%–77.0%; 5194 of 6900 interpretations). Consensus ReferenceDiagnosis Pathologist Interpretation vs Consensus-Derived Reference Diagnosis, % (95% CI) No. ofInterpretations Overall ConcordanceRate OverinterpretationRate UnderinterpretationRate Benign without atypia 2070 87 (85–89) 13 (11–15) Atypia 2070 48 (44–52) 17 (15–21) 35 (31–39) DCIS 2097 84 (82–86) 3 (2–4) 13 (12–15) Invasive carcinoma 663 96 (94–97) 4 (3–6) Disagreement with the reference diagnosis was statistically significantly higher among biopsies from women with higher (n = 122) vs lower (n = 118) breast density on prior mammograms (overall concordance rate, 73% [95% CI, 71%–75%] for higher vs 77% [95% CI, 75%–80%] for lower, P < .001), and among pathologists who interpreted lower weekly case volumes (P < .001) or worked in smaller practices (P = .034) or nonacademic settings (P = .007). CONCLUSIONS AND RELEVANCE In this study of pathologists, in which diagnostic interpretation was based on a single breast biopsy slide, overall agreement between the individual pathologists’ interpretations and the expert consensus–derived reference diagnoses was 75.3%, with the highest level of concordance for invasive carcinoma and lower levels of concordance for DCIS and atypia. Further research is needed to understand the relationship of these findings with patient management. PMID:25781441
-
Lee, Minju; Min, Byung-Hoon; Lee, Hyuk; Ahn, Sangjeong; Lee, Jun Haeng; Rhee, Poong-Lyul; Kim, Jae J.; Sohn, Tae Sung; Kim, Sung; Kim, Kyoung-Mee
2015-01-01
Abstract As treatment decisions for patients with gastric subepithelial tumors (SETs) largely depend on the histopathologic diagnosis, noninvasive and effective tissue acquisition methods are definitely required for proper management of gastric SETs. Recently, a new endoscopic ultrasonography-guided fine needle biopsy (EUS-FNB) device with ProCore reverse bevel technology was developed. We aimed to elucidate the feasibility and diagnostic yield of EUS-FNB with this new core biopsy needle device in patients with gastric SETs. A prospectively maintained database was retrospectively reviewed to identify consecutive patients who underwent EUS-FNB with a 22-gauge ProCore needle for gastric SETs 2 cm or larger. The main outcome measurement was the diagnostic yield of EUS-FNB. Procedure results were categorized into diagnostic, suggestive, or nondiagnostic. Of the 43 patients, needle punctures were successful in all cases irrespective of tumor location. EUS-FNB procedure results were diagnostic in 86.0%, suggestive in 4.7%, and nondiagnostic in 9.3% of cases, respectively. The diagnostic yield was the highest in fundus (100.0%), followed by body (89.5%), cardia (83.3%), and antrum (50.0%). All 18 patients with cardiac SET were finally diagnosed to have leiomyoma, and 16 patients with diagnostic or suggestive results avoided surgery. A heterogeneous echo pattern on EUS was found in 33.3% of cases with nondiagnostic or suggestive results and in 5.4% with diagnostic results. In multivariate analysis, no independent predictor of unsuccessful EUS-FNB with nondiagnostic or suggestive results was identified. Agreement between EUS-FNB and surgical pathology was 100% with respect to the diagnosis of gastrointestinal stromal tumor. However, there was a significant discrepancy in mitotic counts observed between the EUS-FNB and surgical specimens in patients with gastrointestinal stromal tumor. There were no significant procedure-related adverse events during and after the procedures. EUS-FNB with a 22G ProCore needle is a technically feasible, safe, and effective procedure for pathologic diagnosis of gastric SETs. This procedure can help refine surgical indications and facilitate a proper treatment decisions for gastric SETs, especially in the cardia. PMID:26448008
-
Value of percutaneous needle biopsy of small renal tumors in patients referred for cryoablation.
Iguchi, Toshihiro; Hiraki, Takao; Gobara, Hideo; Fujiwara, Hiroyasu; Sakurai, Jun; Matsui, Yusuke; Araki, Motoo; Nasu, Yasutomo; Kanazawa, Susumu
2017-04-01
To retrospectively evaluate the safety and diagnostic yield of needle biopsy of small renal tumors, and the clinical consequences of performing needle biopsy in patients referred for percutaneous cryoablation before their treatment. Biopsy was performed for 120 tumors (mean diameter, 2.2 cm) in 119 patients. All procedures were divided into diagnostic and non-diagnostic biopsies. Various variables were compared between the two groups. All cryoablation procedures were divided into two groups: procedures with or without simultaneous biopsy. The rates of benign or non-diagnostic tumors in each group were compared. After performing 120 initial and eight repeat biopsies, Grade 1 bleedings occurred in 44 cases. Six tumors were non-diagnostic and 114 were pathologically diagnosed. There were no significant variables between the diagnostic and non-diagnostic biopsies. Unnecessary cryoablation was avoided in nine benign lesions by performing biopsy in advance. Cryoablation performed simultaneously with biopsy included significantly more benign or non-diagnostic tumors than cryoablation performed after biopsy (15.2% vs. 1.4%; p = .01). Percutaneous biopsy of small renal tumors referred for cryoablation was a safe procedure with high diagnostic yield. The confirmation of pathological diagnosis prior to cryoablation is necessary because patients with benign tumors can avoid unnecessary treatment.
-
Mills, Anne M; Gradecki, Sarah E; Horton, Bethany J; Blackwell, Rebecca; Moskaluk, Christopher A; Mandell, James W; Mills, Stacey E; Cathro, Helen P
2018-01-01
Prior work has shown that digital images and microscopic slides can be interpreted with comparable diagnostic accuracy. Although accuracy has been well-validated, the interpretative time for digital images has scarcely been studied and concerns about efficiency remain a major barrier to adoption. We investigated the efficiency of digital pathology when compared with glass slide interpretation in the diagnosis of surgical pathology biopsy and resection specimens. Slides were pulled from 510 surgical pathology cases from 5 organ systems (gastrointestinal, gynecologic, liver, bladder, and brain). Original diagnoses were independently confirmed by 2 validating pathologists. Diagnostic slides were scanned using the Philips IntelliSite Pathology Solution. Each case was assessed independently on digital and optical by 3 reading pathologists, with a ≥6 week washout period between modalities. Reading pathologists recorded assessment times for each modality; digital times included time to load the case. Diagnostic accuracy was determined based on whether a rendered diagnosis differed significantly from the original diagnosis. Statistical analysis was performed to assess for differences in interpretative times across modalities. All 3 reading pathologists showed comparable diagnostic accuracy across optical and digital modalities (mean major discordance rates with original diagnosis: 4.8% vs. 4.4%, respectively). Mean assessment times ranged from 1.2 to 9.1 seconds slower on digital versus optical. The slowest reader showed a significant learning effect during the course of the study so that digital assessment times decreased over time and were comparable with optical times by the end of the series. Organ site and specimen type did not significantly influence differences in interpretative times. In summary, digital image reading times compare favorably relative to glass slides across a variety of organ systems and specimen types. Mean increase in assessment time is 4 seconds/case. This time can be minimized with experience and may be further balanced by the improved ease of electronic chart access allowed by digital slide viewing, as well as quantitative assessments which can be expedited on digital images.
-
García-Correa, J J E; Ramírez-García, J J; García-Contreras, L F; Fuentes-Orozco, C; Irusteta-Jiménez, L; Michel-Espinoza, L R; Carballo Uribe, A S; Torres Chávez, J A; González-Ojeda, A
Double-balloon enteroscopy has been improving the visualization of the entire intestine for more than a decade. It is a complementary method in the study of intestinal diseases that enables biopsies to be taken and treatments to be administered. Our aim was to describe its main indications, insertion routes, diagnostic/therapeutic yield, and complications. All patients referred to our unit with suspected small bowel pathology were included. The insertion route (oral/anal) was determined through diagnostic suspicion. The variables measured were: insertion route, small bowel examination extent, endoscopic diagnosis/treatment, biopsy/histopathology report, complications, and surgical findings. The study included 28 double-balloon enteroscopies performed on 23 patients, of which 10 were women and 13 were men (mean age of 52.95 years). The oral approach was the most widely used (n=21), the main indication was overt small bowel bleeding (n=16), and the general diagnostic yield was 65.21%. The therapeutic intervention rate was 39.1% and the procedure was effective in all the cases. The most widely used treatment was argon plasma therapy (n=7). The complication rate was 8.6%; one patient presented with low blood pressure due to active bleeding and another had deep mucosal laceration caused by the argon plasma. Double-balloon enteroscopy is a safe and efficacious method for the study and management of small bowel diseases, with an elevated diagnostic and therapeutic yield. Copyright © 2017 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.
-
Döring, Sophie; Arzi, Boaz; Barich, Catherine R; Hatcher, David C; Kass, Philip H; Verstraete, Frank J M
2018-01-01
OBJECTIVE To evaluate the diagnostic yield of dental radiography (Rad method) and 3 cone-beam CT (CBCT) methods for the identification of predefined anatomic landmarks in brachycephalic dogs. ANIMALS 19 client-owned brachycephalic dogs admitted for evaluation and treatment of dental disease. PROCEDURES 26 predefined anatomic landmarks were evaluated separately by use of the RAD method and 3 CBCT software modules (serial CBCT slices and custom cross sections, tridimensional rendering, and reconstructed panoramic views). A semiquantitative scoring system was used, and mean scores were calculated for each anatomic landmark and imaging method. The Friedman test was used to evaluate values for significant differences in diagnostic yield. For values that were significant, the Wilcoxon signed rank test was used with the Bonferroni-Holm multiple comparison adjustment to determine significant differences among each of the 6 possible pairs of diagnostic methods. RESULTS Differences of diagnostic yield among the Rad and 3 CBCT methods were significant for 19 of 26 anatomic landmarks. For these landmarks, Rad scores were significantly higher than scores for reconstructed panoramic views for 4 of 19 anatomic landmarks, but Rad scores were significantly lower than scores for reconstructed panoramic views for 8 anatomic landmarks, tridimensional rendering for 18 anatomic landmarks, and serial CBCT slices and custom cross sections for all 19 anatomic landmarks. CONCLUSIONS AND CLINICAL RELEVANCE CBCT methods were better suited than dental radiography for the identification of anatomic landmarks in brachycephalic dogs. Results of this study can serve as a basis for CBCT evaluation of dental disorders in brachycephalic dogs.
-
Koh, In J; Han, Seung B; In, Yong; Oh, Kwang J; Lee, Dae H; Kim, Tae K
2017-11-01
Leukocyte esterase (LE) was recently reported to be an accurate marker for diagnosing periprosthetic joint infection (PJI) as defined by the Musculoskeletal Infection Society (MSIS) criteria. However, the diagnostic value of the LE test for PJI after total knee arthroplasty (TKA), the reliability of the subjective visual interpretation of the LE test, and the correlation between the LE test results and the current MSIS criteria remain unclear. This study prospectively enrolled 60 patients undergoing revision TKA for either PJI or aseptic failure. Serological marker, synovial fluid, and histological analyses were performed in all cases. The PJI group comprised 38 cases that met the MSIS criteria and the other 22 cases formed the aseptic group. All the LE tests were interpreted using both visual judgment and automated colorimetric reader. When "++" results were considered to indicate a positive PJI, the sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy were 84, 100, 100, 79, and 90%, respectively. The visual interpretation agreed with the automated colorimetric reader in 90% of cases (Cronbach α = 0.894). The grade of the LE test was strongly correlated with the synovial white blood cell count (ρ = 0.695) and polymorphonuclear leukocyte percentage (ρ = 0.638) and moderately correlated with the serum C-reactive protein and erythrocyte sedimentation rate. The LE test has high diagnostic value for diagnosing PJI after TKA. Subjective visual interpretation of the LE test was reliable and valid for the current battery of PJI diagnostic tests according to the MSIS criteria. Copyright © 2017. Published by Elsevier Inc.
-
Martian Crustal Magnetism: What Have We Learned After Approximately 6 Years of MGS Observations?
NASA Technical Reports Server (NTRS)
Acuna, M. H.
2003-01-01
The MAG/ER investigation aboard the Mars Global Surveyor (MGS) has established conclusively that an internal, dynamo-generated field does not currently exist at Mars and discovered, unexpectedly, strong magnetization in the crust. An estimate of the upper limit of the current Mars dipole moment derived from the MGS data yields M < 2 x 10(exp 17) A-m2, which corresponds to a surface equatorial field strength of < 0.5 nT. The intense magnetization of the crust is closely associated with the ancient, heavily cratered high terrain, which lies south of Mars dichotomy boundary. The correlation of magnetization with the old terrain and the role of impacts, which have modified the magnetic properties of the crust, constitute a new and powerful diagnostic tool that is providing a unique view into the early thermal history of the planet, which was almost totally unknown prior to the arrival of MGS. Data from the Lunar Prospector mission complement contemporary analyses and interpretation of crustal magnetism in planetary system bodies that do not currently possess core dynamos. The observation of magnetic lineations over Terra Sirenum (Sirenum Fossae) and Terra Cimmeria, are suggestive of tectonic processes observed at Earth in association with sea-floor spreading and geomagnetic field reversals. If this association is correct, it would indicate the possible existence of plate tectonics and magnetic field reversals in Mars' early history. Alternative models involving fault/graben formation associated with the fracturing of a thin, magnetized crustal layer by tectonic or volcanism-induced stresses, yield equally valid interpretations. To date, no reliable correlation between topography, geology and crustal magnetism has been established and the origin of these remarkable Martian magnetic anomalies remains a mystery.
-
Beck, Irene R; Schmid, Nicole S; Berres, Manfred; Monsch, Andreas U
2014-06-01
The diagnosis of mild cognitive impairment (MCI) and dementia requires detailed neuropsychological examinations. These examinations typically yield a large number of outcome variables, which may complicate the interpretation and communication of results. The purposes of this study were the following: (i) to reduce a large data set of interrelated neuropsychological variables to a smaller number of cognitive dimensions; (ii) to create a common metric for these dimensions (z-scores); and (iii) to study the ability of the cognitive dimensions to distinguish between groups of patients with different types of cognitive impairment. We tested 1646 patients with different forms of dementia or with a major depression with a standard (n = 632) or, if cognitively less affected, a challenging neuropsychological battery (n = 1014). To identify the underlying cognitive dimensions of the two test batteries, maximum likelihood factor analyses with a promax rotation were conducted. To interpret the sum scores of the factors as standard scores, we divided them by the standard deviation of a cognitively healthy sample (n = 1145). The factor analyses yielded seven factors for each test battery. The cognitive dimensions in both test batteries distinguished patients with different forms of dementia (MCI, Alzheimer's dementia or frontotemporal dementia) and patients with major depression. Furthermore, patients with stable MCI could be separated from patients with progressing MCI. Discriminant analyses with an independent new sample of patients (n = 306) revealed that the new dimension scores distinguished new samples of patients with MCI from patients with Alzheimer's dementia with high accuracy. These findings suggest that these cognitive dimensions may benefit neuropsychological diagnostics. © 2013 The Authors International Journal of Geriatric Psychiatry Published by John Wiley & Sons Ltd.
-
Beck, Irene R; Schmid, Nicole S; Berres, Manfred; Monsch, Andreas U
2014-01-01
Objective The diagnosis of mild cognitive impairment (MCI) and dementia requires detailed neuropsychological examinations. These examinations typically yield a large number of outcome variables, which may complicate the interpretation and communication of results. The purposes of this study were the following: (i) to reduce a large data set of interrelated neuropsychological variables to a smaller number of cognitive dimensions; (ii) to create a common metric for these dimensions (z-scores); and (iii) to study the ability of the cognitive dimensions to distinguish between groups of patients with different types of cognitive impairment. Methods We tested 1646 patients with different forms of dementia or with a major depression with a standard (n = 632) or, if cognitively less affected, a challenging neuropsychological battery (n = 1014). To identify the underlying cognitive dimensions of the two test batteries, maximum likelihood factor analyses with a promax rotation were conducted. To interpret the sum scores of the factors as standard scores, we divided them by the standard deviation of a cognitively healthy sample (n = 1145). Results The factor analyses yielded seven factors for each test battery. The cognitive dimensions in both test batteries distinguished patients with different forms of dementia (MCI, Alzheimer's dementia or frontotemporal dementia) and patients with major depression. Furthermore, patients with stable MCI could be separated from patients with progressing MCI. Discriminant analyses with an independent new sample of patients (n = 306) revealed that the new dimension scores distinguished new samples of patients with MCI from patients with Alzheimer's dementia with high accuracy. Conclusion These findings suggest that these cognitive dimensions may benefit neuropsychological diagnostics. PMID:24227657
-
Simel, David L; Rennie, Drummond; Bossuyt, Patrick M M
2008-06-01
The Standards for Reporting of Diagnostic Accuracy (STARD) statement provided guidelines for investigators conducting diagnostic accuracy studies. We reviewed each item in the statement for its applicability to clinical examination diagnostic accuracy research, viewing each discrete aspect of the history and physical examination as a diagnostic test. Nonsystematic review of the STARD statement. Two former STARD Group participants and 1 editor of a journal series on clinical examination research reviewed each STARD item. Suggested interpretations and comments were shared to develop consensus. The STARD Statement applies generally well to clinical examination diagnostic accuracy studies. Three items are the most important for clinical examination diagnostic accuracy studies, and investigators should pay particular attention to their requirements: describe carefully the patient recruitment process, describe participant sampling and address if patients were from a consecutive series, and describe whether the clinicians were masked to the reference standard tests and whether the interpretation of the reference standard test was masked to the clinical examination components or overall clinical impression. The consideration of these and the other STARD items in clinical examination diagnostic research studies would improve the quality of investigations and strengthen conclusions reached by practicing clinicians. The STARD statement provides a very useful framework for diagnostic accuracy studies. The group correctly anticipated that there would be nuances applicable to studies of the clinical examination. We offer guidance that should enhance their usefulness to investigators embarking on original studies of a patient's history and physical examination.
-
Itri, Jason N; Jones, Lisa P; Kim, Woojin; Boonn, William W; Kolansky, Ana S; Hilton, Susan; Zafar, Hanna M
2014-04-01
Monitoring complications and diagnostic yield for image-guided procedures is an important component of maintaining high quality patient care promoted by professional societies in radiology and accreditation organizations such as the American College of Radiology (ACR) and Joint Commission. These outcome metrics can be used as part of a comprehensive quality assurance/quality improvement program to reduce variation in clinical practice, provide opportunities to engage in practice quality improvement, and contribute to developing national benchmarks and standards. The purpose of this article is to describe the development and successful implementation of an automated web-based software application to monitor procedural outcomes for US- and CT-guided procedures in an academic radiology department. The open source tools PHP: Hypertext Preprocessor (PHP) and MySQL were used to extract relevant procedural information from the Radiology Information System (RIS), auto-populate the procedure log database, and develop a user interface that generates real-time reports of complication rates and diagnostic yield by site and by operator. Utilizing structured radiology report templates resulted in significantly improved accuracy of information auto-populated from radiology reports, as well as greater compliance with manual data entry. An automated web-based procedure log database is an effective tool to reliably track complication rates and diagnostic yield for US- and CT-guided procedures performed in a radiology department.
-
Roth, Kjetil; Hardie, Jon Andrew; Andreassen, Alf Henrik; Leh, Friedemann; Eagan, Tomas Mikal Lind
2009-06-01
The choice of sampling techniques in bronchoscopy with sampling from a visible lesion will depend on the expected diagnostic yields and the costs of the sampling techniques. The aim of this study was to determine the most economical combination of sampling techniques when approaching endobronchial visible lesions. A cost minimization analysis was performed. All bronchoscopies from 2003 and 2004 at Haukeland university hospital, Bergen, Norway, were reviewed retrospectively for diagnostic yields. 162 patients with endobronchial disease were included. Potential sampling techniques used were biopsy, brushing, endobronchial needle aspiration (EBNA) and washings. Costs were estimated based on registration of equipment costs and personnel costs. Sensitivity analyses were performed to determine threshold values. The combination of biopsy, brushing and EBNA was the most economical strategy with an average cost of Euro 893 (95% CI: 657, 1336). The cost of brushing had to be below Euro 83 and it had to increase the diagnostic yield more than 2.2%, for biopsy and brushing to be more economical than biopsy alone. The combination of biopsy, brushing and EBNA was more economical than biopsy and brushing when the cost of EBNA was below Euro 205 and the increase in diagnostic yield was above 5.2%. In the current study setting, biopsy, brushing and EBNA was the most economical combination of sampling techniques for endobronchial visible lesions.
-
Doshi, Ankur M; Huang, Chenchan; Ginocchio, Luke; Shanbhogue, Krishna; Rosenkrantz, Andrew B
2017-12-01
To evaluate the impact of questionnaires completed by patients at the time of abdominopelvic CT performed for abdominal pain on the completeness of clinical information and the identification of potential causes of pain, compared with order requisitions alone. 100 outpatient CT examinations performed for the evaluation of abdominal pain were retrospectively reviewed. The specificity of the location of pain was compared between the order requisition and patient questionnaire. An abdominal imaging fellow (Reader 1) and abdominal radiologist (Reader 2) reviewed the examinations independently in two sessions 6 weeks apart (one with only the order requisition and one also with the questionnaire). Readers recorded identified causes of pain and rated their confidence in interpretation (1-5 scale; least to greatest confidence). In 30% of patients, the questionnaire provided a more specific location for pain. Among these, the pain was localized to a specific quadrant in 40%. With having access to the questionnaire, both readers identified additional causes for pain not identified in session 1 (Reader 1, 8.6% [7/81]; Reader 2 5.3% [4/75]). Additional identified causes of pain included diverticulitis, cystitis, peritoneal implants, epiploic appendagitis, osseous metastatic disease, umbilical hernia, gastritis, and SMA syndrome. Confidence in interpretation was significantly greater using the questionnaire for both readers (Reader 1: 4.8 ± 0.6 vs. 4.0 ± 0.5; Reader 2: 4.9 ± 0.3 vs. 4.7 ± 0.5, p < 0.001). Patient questionnaires provide additional relevant clinical history, increased diagnostic yield, and improve radiologists' confidence. Radiology practices are encouraged to implement questionnaires and make these readily available to radiologists at the time of interpretation.
-
Kelly, Brendan S; Rainford, Louise A; Darcy, Sarah P; Kavanagh, Eoin C; Toomey, Rachel J
2016-07-01
Purpose To investigate the development of chest radiograph interpretation skill through medical training by measuring both diagnostic accuracy and eye movements during visual search. Materials and Methods An institutional exemption from full ethical review was granted for the study. Five consultant radiologists were deemed the reference expert group, and four radiology registrars, five senior house officers (SHOs), and six interns formed four clinician groups. Participants were shown 30 chest radiographs, 14 of which had a pneumothorax, and were asked to give their level of confidence as to whether a pneumothorax was present. Receiver operating characteristic (ROC) curve analysis was carried out on diagnostic decisions. Eye movements were recorded with a Tobii TX300 (Tobii Technology, Stockholm, Sweden) eye tracker. Four eye-tracking metrics were analyzed. Variables were compared to identify any differences between groups. All data were compared by using the Friedman nonparametric method. Results The average area under the ROC curve for the groups increased with experience (0.947 for consultants, 0.792 for registrars, 0.693 for SHOs, and 0.659 for interns; P = .009). A significant difference in diagnostic accuracy was found between consultants and registrars (P = .046). All four eye-tracking metrics decreased with experience, and there were significant differences between registrars and SHOs. Total reading time decreased with experience; it was significantly lower for registrars compared with SHOs (P = .046) and for SHOs compared with interns (P = .025). Conclusion Chest radiograph interpretation skill increased with experience, both in terms of diagnostic accuracy and visual search. The observed level of experience at which there was a significant difference was higher for diagnostic accuracy than for eye-tracking metrics. (©) RSNA, 2016 Online supplemental material is available for this article.
-
Pfundt, Rolph; del Rosario, Marisol; Vissers, Lisenka E.L.M.; Kwint, Michael P.; Janssen, Irene M.; de Leeuw, Nicole; Yntema, Helger G.; Nelen, Marcel R.; Lugtenberg, Dorien; Kamsteeg, Erik-Jan; Wieskamp, Nienke; Stegmann, Alexander P.A.; Stevens, Servi J.C.; Rodenburg, Richard J.T.; Simons, Annet; Mensenkamp, Arjen R.; Rinne, Tuula; Gilissen, Christian; Scheffer, Hans; Veltman, Joris A.; Hehir-Kwa, Jayne Y.
2017-01-01
Purpose: Copy-number variation is a common source of genomic variation and an important genetic cause of disease. Microarray-based analysis of copy-number variants (CNVs) has become a first-tier diagnostic test for patients with neurodevelopmental disorders, with a diagnostic yield of 10–20%. However, for most other genetic disorders, the role of CNVs is less clear and most diagnostic genetic studies are generally limited to the study of single-nucleotide variants (SNVs) and other small variants. With the introduction of exome and genome sequencing, it is now possible to detect both SNVs and CNVs using an exome- or genome-wide approach with a single test. Methods: We performed exome-based read-depth CNV screening on data from 2,603 patients affected by a range of genetic disorders for which exome sequencing was performed in a diagnostic setting. Results: In total, 123 clinically relevant CNVs ranging in size from 727 bp to 15.3 Mb were detected, which resulted in 51 conclusive diagnoses and an overall increase in diagnostic yield of ~2% (ranging from 0 to –5.8% per disorder). Conclusions: This study shows that CNVs play an important role in a broad range of genetic disorders and that detection via exome-based CNV profiling results in an increase in the diagnostic yield without additional testing, bringing us closer to single-test genomics. Genet Med advance online publication 27 October 2016 PMID:28574513
-
Jabari, Hamidreza; Sami, Ramin; Fakhri, Mohammad; Kiani, Arda
2012-01-01
Forceps biopsy is the standard procedure to obtain specimens in endobronchial lesions. New studies have proposed flexible cryoprobe as an accepted alternative method for this technique. Although diagnostic use of the cryobiopsy is confirmed in few studies, there is paucity of data with regard to an optimum protocol for this method since one of the main considerations in cryobiopsy is the freezing time. To evaluate diagnostic yield and safety of endobronchial biopsies using the flexible cryoprobe. Moreover, different freezing times were assessed to propose an optimized protocol for this diagnostic modality. For each patient with a confirmed intrabronchial lesion, diagnostic o value of forceps biopsy, cryobiopsy in three seconds, cryobiopsy in five seconds and combined results of cryobiopsy in both timings were recorded. A total of 60 patients (39 males and 21 females; Mean age 56.7 +/- 13.3) were included. Specimens that were obtained by cryobiopsy in five seconds were significantly larger than those of forceps biopsy and cryobiopsy in three seconds (p < 0.001). We showed that the achieved diagnostic yields for all three methods were not statistically different (p > 0.05). Simultaneous usage of samples produced in both cryobiopsies can significantly improve the diagnostic yield (p = 0.02). Statistical analysis showed that there were no significant differences in case of bleeding frequency among the three sampling methods. This study confirmed safety and feasibility of cryobiopsy. Additionally, combination of sampling with two different cold induction timings would significantly increase sensitivity of this emerging technique..
-
Fritsch, Michael K; Bridge, Julia A; Schuster, Amy E; Perlman, Elizabeth J; Argani, Pedram
2003-01-01
Pediatric small round cell tumors still pose tremendous diagnostic problems. In difficult cases, the ability to detect tumor-specific gene fusion transcripts for several of these neoplasms, including Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/PNET), synovial sarcoma (SS), alveolar rhabdomyosarcoma (ARMS), and desmoplastic small round cell tumor (DSRCT) using reverse transcriptase-polymerase chain reaction (RT-PCR), can be extremely helpful. Few studies to date, however, have systematically examined several different tumor types for the presence of multiple different fusion transcripts in order to determine the specificity and sensitivity of the RT-PCR method, and no study has addressed this issue for formalin-fixed material. The objectives of this study were to address the specificity, sensitivity, and practicality of such an assay applied strictly to formalin-fixed tissue blocks. Our results demonstrate that, for these tumors, the overall sensitivity for detecting each fusion transcript is similar to that reported in the literature for RT-PCR on fresh or formalin-fixed tissues. The specificity of the assay is very high, being essentially 100% for each primer pair when interpreting the results from visual inspection of agarose gels. However, when these same agarose gels were examined using Southern blotting, a small number of tumors also yielded reproducibly detectable weak signals for unexpected fusion products, in addition to a strong signal for the expected fusion product. Fluorescence in situ hybridization (FISH) studies in one such case indicated that a rearrangement that would account for the unexpected fusion was not present, while another case was equivocal. The overall specificity for each primer pair used in this assay ranged from 94 to 100%. Therefore, RT-PCR using formalin-fixed paraffin-embedded tissue sections can be used to detect chimeric transcripts as a reliable, highly sensitive, and highly specific diagnostic assay. However, we strongly suggest that the final interpretation of the results from this assay be viewed in light of the other features of the case, including clinical history, histology, and immunohistochemistry, by the diagnostic pathologist. Additional studies such as FISH may be useful in clarifying the nature of equivocal or unexpected results.
-
Raschke, R A; Gallo, T; Curry, S C; Whiting, T; Padilla-Jones, A; Warkentin, T E; Puri, A
2017-08-01
Essentials We previously published a diagnostic algorithm for heparin-induced thrombocytopenia (HIT). In this study, we validated the algorithm in an independent large healthcare system. The accuracy was 98%, sensitivity 82% and specificity 99%. The algorithm has potential to improve accuracy and efficiency in the diagnosis of HIT. Background Heparin-induced thrombocytopenia (HIT) is a life-threatening drug reaction caused by antiplatelet factor 4/heparin (anti-PF4/H) antibodies. Commercial tests to detect these antibodies have suboptimal operating characteristics. We previously developed a diagnostic algorithm for HIT that incorporated 'four Ts' (4Ts) scoring and a stratified interpretation of an anti-PF4/H enzyme-linked immunosorbent assay (ELISA) and yielded a discriminant accuracy of 0.97 (95% confidence interval [CI], 0.93-1.00). Objectives The purpose of this study was to validate the algorithm in an independent patient population and quantitate effects that algorithm adherence could have on clinical care. Methods A retrospective cohort comprised patients who had undergone anti-PF4/H ELISA and serotonin release assay (SRA) testing in our healthcare system from 2010 to 2014. We determined the algorithm recommendation for each patient, compared recommendations with the clinical care received, and enumerated consequences of discrepancies. Operating characteristics were calculated for algorithm recommendations using SRA as the reference standard. Results Analysis was performed on 181 patients, 10 of whom were ruled in for HIT. The algorithm accurately stratified 98% of patients (95% CI, 95-99%), ruling out HIT in 158, ruling in HIT in 10 and recommending an SRA in 13 patients. Algorithm adherence would have obviated 165 SRAs and prevented 30 courses of unnecessary antithrombotic therapy for HIT. Diagnostic sensitivity was 0.82 (95% CI, 0.48-0.98), specificity 0.99 (95% CI, 0.97-1.00), PPV 0.90 (95% CI, 0.56-0.99) and NPV 0.99 (95% CI, 0.96-1.00). Conclusions An algorithm incorporating 4Ts scoring and a stratified interpretation of the anti-PF4/H ELISA has good operating characteristics and the potential to improve management of suspected HIT patients. © 2017 International Society on Thrombosis and Haemostasis.
-
Brewer, D E
2000-09-01
The results of cardiac tests must always be interpreted through the lens of pretest probabilities created by the history and the physical examination. Tests should be chosen with a clear diagnostic and prognostic purpose in mind. A clear understanding of the relationship between the history and physical examination and more technologic diagnostic testing improves the primary care physician's ability to evaluate potential cardiac disease in an efficient and cost-effective manner.
-
Interpretation of diagnostic data: 5. How to do it with simple maths.
1983-11-01
The use of simple maths with the likelihood ratio strategy fits in nicely with our clinical views. By making the most out of the entire range of diagnostic test results (i.e., several levels, each with its own likelihood ratio, rather than a single cut-off point and a single ratio) and by permitting us to keep track of the likelihood that a patient has the target disorder at each point along the diagnostic sequence, this strategy allows us to place patients at an extremely high or an extremely low likelihood of disease. Thus, the numbers of patients with ultimately false-positive results (who suffer the slings of labelling and the arrows of needless therapy) and of those with ultimately false-negative results (who therefore miss their chance for diagnosis and, possibly, efficacious therapy) will be dramatically reduced. The following guidelines will be useful in interpreting signs, symptoms and laboratory tests with the likelihood ratio strategy: Seek out, and demand from the clinical or laboratory experts who ought to know, the likelihood ratios for key symptoms and signs, and several levels (rather than just the positive and negative results) of diagnostic test results. Identify, when feasible, the logical sequence of diagnostic tests. Estimate the pretest probability of disease for the patient, and, using either the nomogram or the conversion formulas, apply the likelihood ratio that corresponds to the first diagnostic test result. While remembering that the resulting post-test probability or odds from the first test becomes the pretest probability or odds for the next diagnostic test, repeat the process for all the pertinent symptoms, signs and laboratory studies that pertain to the target disorder. However, these combinations may not be independent, and convergent diagnostic tests, if treated as independent, will combine to overestimate the final post-test probability of disease. You are now far more sophisticated in interpreting diagnostic tests than most of your teachers. In the last part of our series we will show you some rather complex strategies that combine diagnosis and therapy, quantify our as yet nonquantified ideas about use, and require the use of at least a hand calculator.
-
Interpretation of diagnostic data: 5. How to do it with simple maths.
1983-01-01
The use of simple maths with the likelihood ratio strategy fits in nicely with our clinical views. By making the most out of the entire range of diagnostic test results (i.e., several levels, each with its own likelihood ratio, rather than a single cut-off point and a single ratio) and by permitting us to keep track of the likelihood that a patient has the target disorder at each point along the diagnostic sequence, this strategy allows us to place patients at an extremely high or an extremely low likelihood of disease. Thus, the numbers of patients with ultimately false-positive results (who suffer the slings of labelling and the arrows of needless therapy) and of those with ultimately false-negative results (who therefore miss their chance for diagnosis and, possibly, efficacious therapy) will be dramatically reduced. The following guidelines will be useful in interpreting signs, symptoms and laboratory tests with the likelihood ratio strategy: Seek out, and demand from the clinical or laboratory experts who ought to know, the likelihood ratios for key symptoms and signs, and several levels (rather than just the positive and negative results) of diagnostic test results. Identify, when feasible, the logical sequence of diagnostic tests. Estimate the pretest probability of disease for the patient, and, using either the nomogram or the conversion formulas, apply the likelihood ratio that corresponds to the first diagnostic test result. While remembering that the resulting post-test probability or odds from the first test becomes the pretest probability or odds for the next diagnostic test, repeat the process for all the pertinent symptoms, signs and laboratory studies that pertain to the target disorder. However, these combinations may not be independent, and convergent diagnostic tests, if treated as independent, will combine to overestimate the final post-test probability of disease. You are now far more sophisticated in interpreting diagnostic tests than most of your teachers. In the last part of our series we will show you some rather complex strategies that combine diagnosis and therapy, quantify our as yet nonquantified ideas about use, and require the use of at least a hand calculator. PMID:6671182
-
Downscattered Neutron Imaging for ICF
NASA Astrophysics Data System (ADS)
Moran, Michael; Haan, Steven; Hatchett, Stephen; Izumi, Nobuhiko; Koch, Jeffrey; Lerche, Richard; Phillips, Thomas
2002-11-01
Diagnostics which measure the performance of implosions are critical for the success of ignition. Neutron yield, fusion-burn time history, and images are examples of important diagnostics. Neutron and x-ray images will record the geometries of compressed targets during the fusion-burn process. Such images provide a critical test of the accuracy of numerical modeling of ICF experiments. Imaging of downscattered neutrons, by using energy-resolved detection, offers the intriguing advantage of being able to provide independent images of burning and non-burning regions of the nuclear fuel. The usefulness of downscattered neutron imaging depends on both the information content of the data and on the quality of the data that can be recorded. The information content will relate to the characteristic neutron spectra that are associated with emission from different regions of the source. Numerical modeling of ICF fusion burn will be required to interpret the corresponding energy-dependent images. The exercise will be useful only if the images can be recorded with sufficient definition to reveal the spatial and energy-dependent features of interest. Several options are being evaluated with respect to the feasibility of providing the desired simultaneous spatial and energy resolution. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.
-
ERIC Educational Resources Information Center
Kunina-Habenicht, Olga; Rupp, André A.; Wilhelm, Oliver
2017-01-01
Diagnostic classification models (DCMs) hold great potential for applications in summative and formative assessment by providing discrete multivariate proficiency scores that yield statistically driven classifications of students. Using data from a newly developed diagnostic arithmetic assessment that was administered to 2032 fourth-grade students…
-
ERIC Educational Resources Information Center
Zhang, Jie; Wheeler, John J.
2010-01-01
The prevalence of autism has increased approximately four times in children in nearly one decade (California Health and Human Services Agency, 2003). It has been reported that explanations such as immigration, shifts in the interpretation of diagnostic criteria, improved identification, or diagnostic accuracies cannot explain the observed increase…
-
A reassessment of ground water flow conditions and specific yield at Borden and Cape Cod
Grimestad, Garry
2002-01-01
Recent widely accepted findings respecting the origin and nature of specific yield in unconfined aquifers rely heavily on water level changes observed during two pumping tests, one conducted at Borden, Ontario, Canada, and the other at Cape Cod, Massachusetts. The drawdown patterns observed during those tests have been taken as proof that unconfined specific yield estimates obtained from long-duration pumping tests should approach the laboratory-estimated effective porosity of representative aquifer formation samples. However, both of the original test reports included direct or referential descriptions of potential supplemental sources of pumped water that would have introduced intractable complications and errors into straightforward interpretations of the drawdown observations if actually present. Searches for evidence of previously neglected sources were performed by screening the original drawdown observations from both locations for signs of diagnostic skewing that should be present only if some of the extracted water was derived from sources other than main aquifer storage. The data screening was performed using error-guided computer assisted fitting techniques, capable of accurately sensing and simulating the effects of a wide range of non-traditional and external sources. The drawdown curves from both tests proved to be inconsistent with traditional single-source pumped aquifer models but consistent with site-specific alternatives that included significant contributions of water from external sources. The corrected pumping responses shared several important features. Unsaturated drainage appears to have ceased effectively at both locations within the first day of pumping, and estimates of specific yield stabilized at levels considerably smaller than the corresponding laboratory-measured or probable effective porosity. Separate sequential analyses of progressively later field observations gave stable and nearly constant specific yield estimates for each location, with no evidence from either test that more prolonged pumping would have induced substantially greater levels of unconfined specific yield.
-
Sehgal, Inderpaul Singh; Dhooria, Sahajal; Aggarwal, Ashutosh Nath; Agarwal, Ritesh
2018-04-01
Whether the use of rapid on-site cytologic evaluation (ROSE) increases the diagnostic yield of transbronchial needle aspiration (TBNA) remains unclear. This article is a systematic review of studies describing the utility of ROSE in subjects undergoing TBNA. The study included a systematic review of the PubMed, Embase, and Scopus databases for randomized controlled trials investigating the diagnostic yield of conventional transbronchial needle aspiration (c-TBNA) or endobronchial ultrasound (EBUS)-TBNA, with or without ROSE, in subjects with mediastinal lymphadenopathy. Five studies (618 subjects; two EBUS-TBNA, two c-TBNA, and one both) were identified. Overall, the studies were of good quality. The pooled risk difference (95% CI) of the diagnostic yield of EBUS-TBNA and c-TBNA was 0.04 (-0.01 to 0.09) and 0.12 (-0.08 to 0.33), respectively, suggesting no added benefit with ROSE. The use of ROSE during EBUS-TBNA (but not c-TBNA) resulted in significantly fewer needle passes (mean difference [95% CI], -1.1 [-2.2 to -0.005]; P < .001). There was no difference in the procedure time during EBUS-TBNA. The complication rate was significantly lower (OR [95% CI], 0.26 [0.10 to 0.71]; P = .009) when ROSE was used during c-TBNA due to fewer additional procedures required to make a diagnosis. There was evidence of heterogeneity in the studies involving c-TBNA but not EBUS-TBNA. There was no publication bias. The use of ROSE neither improved the diagnostic yield nor reduced the procedure time during TBNA. However, the use of ROSE was associated with fewer number of needle passes during EBUS-TBNA and overall lower requirement for additional bronchoscopy procedures during TBNA to make a final diagnosis. PROSPERO; No.: CRD42017058937; URL: www.crd.york.ac.uk/prospero/. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.
-
Professional Acceptance Of Electronic Images In Radiologic Practice
NASA Astrophysics Data System (ADS)
Gitlin, Joseph N.; Curtis, David J.; Kerlin, Barbara D.; Olmsted, William W.
1983-05-01
During the past four years, a large number of radiographic images have been interpreted in both film and video modes in an effort to determine the utility of digital/analogue systems in general practice. With the cooperation of the Department of Defense, the MITRE Corporation, and several university-based radiology departments, the Public Health Service has participated in laboratory experiments and a teleradiology field trial to meet this objective. During the field trial, 30 radiologists participated in the interpretation of more than 4,000 diagnostic x-ray examinations that were performed at distant clinics, digitized, and transmitted to a medical center for interpretation on video monitors. As part of the evaluation, all of the participating radiologists and the attending physicians at the clinics were queried regarding the teleradiology system, particularly with respect to the diagnostic quality of the electronic images. The original films for each of the 4,000 examinations were read independently, and the findings and impressions from each mode were compared to identify discrepancies. In addition, a sample of 530 cases was reviewed and interpreted by a consensus panel to measure the accuracy of findings and impressions of both film and video readings. The sample has been retained in an automated archive for future study at the National Center of Devices and Radiological Health facilities in Rockville, Maryland. The studies include a comparison of diagnostic findings and impressions from 1024 x 1024 matrices with those obtained from the 512 x 512 format used in the field trial. The archive also provides a database for determining the effect of data compression techniques on diagnostic interpretations and establishing the utility of image processing algorithms. The paper will include an analysis of the final results of the field trial and preliminary findings from the ongoing studies using the archive of cases at the National Center for Devices and Radiological Health. This paper was not available at the time of printing of the Proceedings.
-
Computed Tomography Window Blending: Feasibility in Thoracic Trauma.
Mandell, Jacob C; Wortman, Jeremy R; Rocha, Tatiana C; Folio, Les R; Andriole, Katherine P; Khurana, Bharti
2018-02-07
This study aims to demonstrate the feasibility of processing computed tomography (CT) images with a custom window blending algorithm that combines soft-tissue, bone, and lung window settings into a single image; to compare the time for interpretation of chest CT for thoracic trauma with window blending and conventional window settings; and to assess diagnostic performance of both techniques. Adobe Photoshop was scripted to process axial DICOM images from retrospective contrast-enhanced chest CTs performed for trauma with a window-blending algorithm. Two emergency radiologists independently interpreted the axial images from 103 chest CTs with both blended and conventional windows. Interpretation time and diagnostic performance were compared with Wilcoxon signed-rank test and McNemar test, respectively. Agreement with Nexus CT Chest injury severity was assessed with the weighted kappa statistic. A total of 13,295 images were processed without error. Interpretation was faster with window blending, resulting in a 20.3% time saving (P < .001), with no difference in diagnostic performance, within the power of the study to detect a difference in sensitivity of 5% as determined by post hoc power analysis. The sensitivity of the window-blended cases was 82.7%, compared to 81.6% for conventional windows. The specificity of the window-blended cases was 93.1%, compared to 90.5% for conventional windows. All injuries of major clinical significance (per Nexus CT Chest criteria) were correctly identified in all reading sessions, and all negative cases were correctly classified. All readers demonstrated near-perfect agreement with injury severity classification with both window settings. In this pilot study utilizing retrospective data, window blending allows faster preliminary interpretation of axial chest CT performed for trauma, with no significant difference in diagnostic performance compared to conventional window settings. Future studies would be required to assess the utility of window blending in clinical practice. Copyright © 2018 The Association of University Radiologists. All rights reserved.
-
Rational manipulation of digital EEG: pearls and pitfalls.
Seneviratne, Udaya
2014-12-01
The advent of digital EEG has provided greater flexibility and more opportunities in data analysis to optimize the diagnostic yield. Changing the filter settings, sensitivity, montages, and time-base are possible rational manipulations to achieve this goal. The options to use polygraphy, video, and quantification are additional useful features. Aliasing and loss of data are potential pitfalls in the use of digital EEG. This review illustrates some common clinical scenarios where rational manipulations can enhance the diagnostic EEG yield and potential pitfalls in the process.
-
Arias, Sixto; Lee, Hans; Semaan, Roy; Frimpong, Bernice; Ortiz, Ricardo; Feller-Kopman, David; Oakjones-Burgess, Karen; Yarmus, Lonny
2015-05-23
Lung nodule evaluation represents a clinical challenge especially in patients with intermediate risk for malignancy. Multiple technologies are presently available to sample nodules for pathological diagnosis. Those technologies can be divided into bronchoscopic and non-bronchoscopic interventions. Electromagnetic navigational bronchoscopy is being extensively used for the endobronchial approach to peripheral lung nodules but has been hindered by anatomic challenges resulting in a 70% diagnostic yield. Electromagnetic navigational guided transthoracic needle lung biopsy is novel non-bronchoscopic method that uses a percutaneous electromagnetic tip tracked needle to obtain core biopsy specimens. Electromagnetic navigational transthoracic needle aspiration complements bronchoscopic techniques potentially allowing the provider to maximize the diagnostic yield during one single procedure. This article describes a novel integrated diagnostic approach to pulmonary lung nodules. We propose the use of endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) for mediastinal staging; radial EBUS, navigational bronchoscopy and E-TTNA during one single procedure to maximize diagnostic yield and minimize the number of invasive procedures needed to obtain a diagnosis. This manuscript describes in detail how the navigation transthoracic procedure is performed. Additional clinical studies are needed to determine the clinical utility of this novel technology.
-
Validity Arguments for Diagnostic Assessment Using Automated Writing Evaluation
ERIC Educational Resources Information Center
Chapelle, Carol A.; Cotos, Elena; Lee, Jooyoung
2015-01-01
Two examples demonstrate an argument-based approach to validation of diagnostic assessment using automated writing evaluation (AWE). "Criterion"®, was developed by Educational Testing Service to analyze students' papers grammatically, providing sentence-level error feedback. An interpretive argument was developed for its use as part of…
-
Lionel, Anath C; Costain, Gregory; Monfared, Nasim; Walker, Susan; Reuter, Miriam S; Hosseini, S Mohsen; Thiruvahindrapuram, Bhooma; Merico, Daniele; Jobling, Rebekah; Nalpathamkalam, Thomas; Pellecchia, Giovanna; Sung, Wilson W L; Wang, Zhuozhi; Bikangaga, Peter; Boelman, Cyrus; Carter, Melissa T; Cordeiro, Dawn; Cytrynbaum, Cheryl; Dell, Sharon D; Dhir, Priya; Dowling, James J; Heon, Elise; Hewson, Stacy; Hiraki, Linda; Inbar-Feigenberg, Michal; Klatt, Regan; Kronick, Jonathan; Laxer, Ronald M; Licht, Christoph; MacDonald, Heather; Mercimek-Andrews, Saadet; Mendoza-Londono, Roberto; Piscione, Tino; Schneider, Rayfel; Schulze, Andreas; Silverman, Earl; Siriwardena, Komudi; Snead, O Carter; Sondheimer, Neal; Sutherland, Joanne; Vincent, Ajoy; Wasserman, Jonathan D; Weksberg, Rosanna; Shuman, Cheryl; Carew, Chris; Szego, Michael J; Hayeems, Robin Z; Basran, Raveen; Stavropoulos, Dimitri J; Ray, Peter N; Bowdin, Sarah; Meyn, M Stephen; Cohn, Ronald D; Scherer, Stephen W; Marshall, Christian R
2018-01-01
Purpose Genetic testing is an integral diagnostic component of pediatric medicine. Standard of care is often a time-consuming stepwise approach involving chromosomal microarray analysis and targeted gene sequencing panels, which can be costly and inconclusive. Whole-genome sequencing (WGS) provides a comprehensive testing platform that has the potential to streamline genetic assessments, but there are limited comparative data to guide its clinical use. Methods We prospectively recruited 103 patients from pediatric non-genetic subspecialty clinics, each with a clinical phenotype suggestive of an underlying genetic disorder, and compared the diagnostic yield and coverage of WGS with those of conventional genetic testing. Results WGS identified diagnostic variants in 41% of individuals, representing a significant increase over conventional testing results (24% P = 0.01). Genes clinically sequenced in the cohort (n = 1,226) were well covered by WGS, with a median exonic coverage of 40 × ±8 × (mean ±SD). All the molecular diagnoses made by conventional methods were captured by WGS. The 18 new diagnoses made with WGS included structural and non-exonic sequence variants not detectable with whole-exome sequencing, and confirmed recent disease associations with the genes PIGG, RNU4ATAC, TRIO, and UNC13A. Conclusion WGS as a primary clinical test provided a higher diagnostic yield than conventional genetic testing in a clinically heterogeneous cohort. PMID:28771251
-
Vitrectomy for the diagnosis and management of uveitis of unknown cause.
Margolis, Ron; Brasil, Oswaldo F M; Lowder, Careen Y; Singh, Rishi P; Kaiser, Peter K; Smith, Scott D; Perez, Victor L; Sonnie, Christine; Sears, Jonathan E
2007-10-01
To determine the diagnostic yield of tests commonly used for vitreous fluid analysis in eyes with suspected intraocular infection or malignancy. Noncomparative interventional case series. Forty-four consecutive patients (45 eyes) treated from 1998 through 2006 with posterior segment inflammation who underwent pars plana vitrectomy for diagnostic purposes. Vitreous specimens obtained via pars plana vitrectomy were analyzed by microbiologic culture, cytologic analysis, and flow cytometry. Diagnostic yield and sensitivity of each test performed on vitreous specimens and visual outcomes of eyes that underwent diagnostic vitrectomy (DVx). Preoperative diagnoses were infection in 15 eyes and malignancy in 30 eyes. Overall, vitreous analysis identified a specific cause in 9 (20%) of 45 eyes. The overall sensitivity of DVx was 63.6%. The sensitivities of individual tests were: culture, 50%; cytologic analysis, 66.7%; and flow cytometry, 83.3%. The yields of diagnostic tests were: culture, 5.7%; cytologic analysis, 14.3%; and flow cytometry, 20.6%. Final diagnoses were infection in 6 eyes, malignancy in 9 eyes, and idiopathic in 30 eyes. Mean visual acuity improved significantly in the first 6 months after DVx. Visual acuity improved in 60% of eyes, with 37.8% of eyes improving by 3 lines or more. Analysis of vitreous fluid by widely available tests is useful in identifying intraocular infection or malignancy. Most patients experienced a substantial improvement in vision.
-
Bartoletti, A; Bocconcelli, P; De Santo, T; Ghidini Ottonelli, A; Giuli, S; Massa, R; Svetlich, C; Tarsi, G; Corbucci, G; Tronconi, F; Vitale, E
2013-08-01
Aim of the study was to compare the diagnostic yield of implantable loop recorders (ILR) of two successive generations for the assessment of syncope. Data on patients who had undergone ILR implantation for unexplained syncope in four Italian public hospitals were retrospectively acquired from the Medtronic Clinical Service database. After implantation, routine follow-up examinations were performed every 90 days, while urgent examinations were carried out in the event of syncope recurrence. The following findings were regarded as diagnostic: ECG documentation of a syncope recurrence; documentation of any of the arrhythmias listed by the current guidelines as diagnostic findings even if asymptomatic. Between November 2002 and March 2010, 107 patients received an ILR (40 Medtronic Reveal® Plus; 67 Medtronic Reveal® DX/XT) and underwent at least one follow-up examination. Diagnoses were made in 7 (17.5%) and 24 (35.8%) (P=0.043) patients, with a median time of 228 and 65 days, respectively. Three (42.9%) and 21 (87.5%) (P=0.029) diagnoses were based on automatically detected events, while adverse outcomes occurred in 6 and in 1 (P=0.01) patients, respectively. Our results show that the new-generation device offer a higher diagnostic yield, mainly as a result of its improved automatic detection function, and is associated with fewer adverse outcomes.
-
Lionel, Anath C; Costain, Gregory; Monfared, Nasim; Walker, Susan; Reuter, Miriam S; Hosseini, S Mohsen; Thiruvahindrapuram, Bhooma; Merico, Daniele; Jobling, Rebekah; Nalpathamkalam, Thomas; Pellecchia, Giovanna; Sung, Wilson W L; Wang, Zhuozhi; Bikangaga, Peter; Boelman, Cyrus; Carter, Melissa T; Cordeiro, Dawn; Cytrynbaum, Cheryl; Dell, Sharon D; Dhir, Priya; Dowling, James J; Heon, Elise; Hewson, Stacy; Hiraki, Linda; Inbar-Feigenberg, Michal; Klatt, Regan; Kronick, Jonathan; Laxer, Ronald M; Licht, Christoph; MacDonald, Heather; Mercimek-Andrews, Saadet; Mendoza-Londono, Roberto; Piscione, Tino; Schneider, Rayfel; Schulze, Andreas; Silverman, Earl; Siriwardena, Komudi; Snead, O Carter; Sondheimer, Neal; Sutherland, Joanne; Vincent, Ajoy; Wasserman, Jonathan D; Weksberg, Rosanna; Shuman, Cheryl; Carew, Chris; Szego, Michael J; Hayeems, Robin Z; Basran, Raveen; Stavropoulos, Dimitri J; Ray, Peter N; Bowdin, Sarah; Meyn, M Stephen; Cohn, Ronald D; Scherer, Stephen W; Marshall, Christian R
2018-04-01
PurposeGenetic testing is an integral diagnostic component of pediatric medicine. Standard of care is often a time-consuming stepwise approach involving chromosomal microarray analysis and targeted gene sequencing panels, which can be costly and inconclusive. Whole-genome sequencing (WGS) provides a comprehensive testing platform that has the potential to streamline genetic assessments, but there are limited comparative data to guide its clinical use.MethodsWe prospectively recruited 103 patients from pediatric non-genetic subspecialty clinics, each with a clinical phenotype suggestive of an underlying genetic disorder, and compared the diagnostic yield and coverage of WGS with those of conventional genetic testing.ResultsWGS identified diagnostic variants in 41% of individuals, representing a significant increase over conventional testing results (24%; P = 0.01). Genes clinically sequenced in the cohort (n = 1,226) were well covered by WGS, with a median exonic coverage of 40 × ±8 × (mean ±SD). All the molecular diagnoses made by conventional methods were captured by WGS. The 18 new diagnoses made with WGS included structural and non-exonic sequence variants not detectable with whole-exome sequencing, and confirmed recent disease associations with the genes PIGG, RNU4ATAC, TRIO, and UNC13A.ConclusionWGS as a primary clinical test provided a higher diagnostic yield than conventional genetic testing in a clinically heterogeneous cohort.
-
Seijo, Luis M; Flandes, Javier; Somiedo, Maria V; Naya, Alba; Manjón, Josefina; Álvarez, Susana; Fernández-Navamuel, Iker
2016-01-01
Bronchoalveolar lavage (BAL) may be performed using a hand-held syringe or wall suction. The aim was to study BAL volume and diagnostic yields based on BAL technique. A total of 220 consecutive patients undergoing BAL at our center were included. Manual aspiration was performed in 115 patients (group 1), and wall suction (<50 mm Hg of negative pressure) was used in 105 patients (group 2). All bronchoscopies were performed under conscious sedation applying topical anesthesia with lidocaine. Three 50-ml sterile saline aliquots were instilled in all patients. The mean total amount of fluid recovered was 67 ± 20 ml in group 1 and 55 ± 22 ml in group 2 (p < 0.001). More patients in the manual aspiration group met American Thoracic Society criteria (recovery of ≥30% of instilled fluid) for an optimal BAL (81 vs. 59%; p < 0.001). The quantity of recovered fluid was also related to BAL location (p < 0.001) and radiologic findings (p = 0.002). Forty-eight (22%) BALs were diagnostic (23 in group 1 and 25 in group 2), including 37 positive bacterial cultures, 6 positive stains for Pneumocystis, and 5 cases of malignancy. No statistically significant difference in diagnostic yield was observed between the two groups. A BAL diagnosis was more likely in patients with certain radiologic (p = 0.033) and endoscopic findings (p = 0.001). When taking into account all bronchoscopic techniques performed during the procedure (e.g. biopsies, brushing, etc.), bronchoscopy was diagnostic in 37% of patients. Manual aspiration is superior to wall suction during BAL yielding a larger quantity of aspirate. Diagnostic yields are similar for both techniques. © 2016 S. Karger AG, Basel.
-
Lindley, Sarah W; Gillies, Elizabeth M; Hassell, Lewis A
2014-10-01
Surgical pathologists use a variety of phrases to communicate varying degrees of diagnostic certainty which have the potential to be interpreted differently than intended. This study sought to: (1) assess the setting, varieties and frequency of use of phrases of diagnostic uncertainty in the diagnostic line of surgical pathology reports, (2) evaluate use of uncertainty expressions by experience and gender, (3) determine how these phrases are interpreted by clinicians and pathologists, and (4) assess solutions to this communication problem. We evaluated 1500 surgical pathology reports to determine frequency of use of uncertainty terms, identified those most commonly used, and looked for variations in usage rates on the basis of case type, experience and gender. We surveyed 76 physicians at tumor boards who were asked to assign a percentage of certainty to diagnoses containing expressions of uncertainty. We found expressions of uncertainty in 35% of diagnostic reports, with no statistically significant difference in usage based on age or gender. We found wide variation in the percentage of certainty clinicians assigned to the phrases studied. We conclude that non-standardized language used in the communication of diagnostic uncertainty is a significant source of miscommunication, both amongst pathologists and between pathologists and clinicians. Copyright © 2014 The Authors. Published by Elsevier GmbH.. All rights reserved.
-
Might telesonography be a new useful diagnostic tool aboard merchant ships? A pilot study.
Nikolić, Nebojsa; Mozetić, Vladimir; Modrcin, Bob; Jaksić, Slaven
2006-01-01
Developments of new, ultra-light diagnostic ultrasound systems (UTS) and modern satellite telecommunication networks are opening new potential applications for diagnostic sonography. One such area is maritime medicine. It is our belief that ship officers can be trained to use diagnostic ultrasound systems with the aim to generate ultrasound images of sufficient quality to be interpreted by medical professionals qualified to read sonograms. To test our thesis we included lectures and hands on scanning practice to the current maritime medicine curriculum at the Faculty of Maritime Studies at the University of Rijeka. Following the didactic and practical training all participating students examined several patients, some with pathology some without. Images obtained by students were then submitted for interpretation to a qualified physician (specialist of general surgery trained in UTS) who was unaware of the patient's pathology. In total, 37 students performed 37 examinations and made 45 ultrasound images, on 3 patients. In this paper, results on this pilot study are presented. It is possible to teach ship officers to produce diagnostically usable ultrasound pictures aboard ships at sea. But before reaching final conclusion about applicability of telesonography on board merchant ships, further studies are necessary, that would include studies of economic feasibility, and on validity of introducing such a diagnostic tool to the maritime medical practice.
-
Oster, Natalia V; Carney, Patricia A; Allison, Kimberly H; Weaver, Donald L; Reisch, Lisa M; Longton, Gary; Onega, Tracy; Pepe, Margaret; Geller, Berta M; Nelson, Heidi D; Ross, Tyler R; Tosteson, Aanna N A; Elmore, Joann G
2013-02-05
Diagnostic test sets are a valuable research tool that contributes importantly to the validity and reliability of studies that assess agreement in breast pathology. In order to fully understand the strengths and weaknesses of any agreement and reliability study, however, the methods should be fully reported. In this paper we provide a step-by-step description of the methods used to create four complex test sets for a study of diagnostic agreement among pathologists interpreting breast biopsy specimens. We use the newly developed Guidelines for Reporting Reliability and Agreement Studies (GRRAS) as a basis to report these methods. Breast tissue biopsies were selected from the National Cancer Institute-funded Breast Cancer Surveillance Consortium sites. We used a random sampling stratified according to woman's age (40-49 vs. ≥50), parenchymal breast density (low vs. high) and interpretation of the original pathologist. A 3-member panel of expert breast pathologists first independently interpreted each case using five primary diagnostic categories (non-proliferative changes, proliferative changes without atypia, atypical ductal hyperplasia, ductal carcinoma in situ, and invasive carcinoma). When the experts did not unanimously agree on a case diagnosis a modified Delphi method was used to determine the reference standard consensus diagnosis. The final test cases were stratified and randomly assigned into one of four unique test sets. We found GRRAS recommendations to be very useful in reporting diagnostic test set development and recommend inclusion of two additional criteria: 1) characterizing the study population and 2) describing the methods for reference diagnosis, when applicable.
-
Enhanced CT images by the wavelet transform improving diagnostic accuracy of chest nodules.
Guo, Xiuhua; Liu, Xiangye; Wang, Huan; Liang, Zhigang; Wu, Wei; He, Qian; Li, Kuncheng; Wang, Wei
2011-02-01
The objective of this study was to compare the diagnostic accuracy in the interpretation of chest nodules using original CT images versus enhanced CT images based on the wavelet transform. The CT images of 118 patients with cancers and 60 with benign nodules were used in this study. All images were enhanced through an algorithm based on the wavelet transform. Two experienced radiologists interpreted all the images in two reading sessions. The reading sessions were separated by a minimum of 1 month in order to minimize the effect of observer's recall. The Mann-Whitney U nonparametric test was used to analyze the interpretation results between original and enhanced images. The Kruskal-Wallis H nonparametric test of K independent samples was used to investigate the related factors which could affect the diagnostic accuracy of observers. The area under the ROC curves for the original and enhanced images was 0.681 and 0.736, respectively. There is significant difference in diagnosing the malignant nodules between the original and enhanced images (z = 7.122, P < 0.001), whereas there is no significant difference in diagnosing the benign nodules (z = 0.894, P = 0.371). The results showed that there is significant difference between original and enhancement images when the size of nodules was larger than 2 cm (Z = -2.509, P = 0.012, indicating the size of the nodules is a critical evaluating factor of the diagnostic accuracy of observers). This study indicated that the image enhancement based on wavelet transform could improve the diagnostic accuracy of radiologists for the malignant chest nodules.
-
Final Report on X-ray Yields from OMEGA II Targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fournier, K B; May, M J; MacLaren, S A
2007-06-20
We present details about X-ray yields measured with Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL) diagnostics in soft and moderately hard X-ray bands from laser-driven, doped-aerogel targets shot on 07/14/06 during the OMEGA II test series. Yields accurate to {+-}25% in the 5-15 keV band are measured with Livermore's HENWAY spectrometer. Yields in the sub-keV to 3.2 keV band are measured with LLNL's DANTE diagnostic, the DANTE yields are accurate to 10-15%. SNL ran a PCD-based diagnostic that also measured X-ray yields in the spectral region above 4 keV, and also down to the sub-keV range. Themore » PCD and HENWAY and DANTE numbers are compared. The time histories of the moderately hard (h{nu} > 4 keV) X-ray signals are measured with LLNL's H11 PCD, and from two SNL PCDs with comparable filtration. There is general agreement between the H11 PCD and SNL PCD measured FWHM except for two of the shorter-laser-pulse shots, which is shown not to be due to analysis techniques. The recommended X-ray waveform is that from the SNL PCD p66k10, which was recorded on a fast, high-bandwidth TDS 6804 oscilloscope. X-ray waveforms from target emission in two softer spectral bands are also shown; the X-ray emissions have increasing duration as the spectral content gets softer.« less
-
Cryobiopsy: should this be used in place of endobronchial forceps biopsies?
Rubio, Edmundo R; le, Susanti R; Whatley, Ralph E; Boyd, Michael B
2013-01-01
Forceps biopsies of airway lesions have variable yields. The yield increases when combining techniques in order to collect more material. With the use of cryotherapy probes (cryobiopsy) larger specimens can be obtained, resulting in an increase in the diagnostic yield. However, the utility and safety of cryobiopsy with all types of lesions, including flat mucosal lesions, is not established. Demonstrate the utility/safety of cryobiopsy versus forceps biopsy to sample exophytic and flat airway lesions. Teaching hospital-based retrospective analysis. Retrospective analysis of patients undergoing cryobiopsies (singly or combined with forceps biopsies) from August 2008 through August 2010. Statistical Analysis. Wilcoxon signed-rank test. The comparative analysis of 22 patients with cryobiopsy and forceps biopsy of the same lesion showed the mean volumes of material obtained with cryobiopsy were significantly larger (0.696 cm(3) versus 0.0373 cm(3), P = 0.0014). Of 31 cryobiopsies performed, one had minor bleeding. Cryopbiopsy allowed sampling of exophytic and flat lesions that were located centrally or distally. Cryobiopsies were shown to be safe, free of artifact, and provided a diagnostic yield of 96.77%. Cryobiopsy allows safe sampling of exophytic and flat airway lesions, with larger specimens, excellent tissue preservation and high diagnostic accuracy.
-
Rennie, Drummond; Bossuyt, Patrick M. M.
2008-01-01
Summary Objective The Standards for Reporting of Diagnostic Accuracy (STARD) statement provided guidelines for investigators conducting diagnostic accuracy studies. We reviewed each item in the statement for its applicability to clinical examination diagnostic accuracy research, viewing each discrete aspect of the history and physical examination as a diagnostic test. Setting Nonsystematic review of the STARD statement. Interventions Two former STARD Group participants and 1 editor of a journal series on clinical examination research reviewed each STARD item. Suggested interpretations and comments were shared to develop consensus. Measurements and Main Results The STARD Statement applies generally well to clinical examination diagnostic accuracy studies. Three items are the most important for clinical examination diagnostic accuracy studies, and investigators should pay particular attention to their requirements: describe carefully the patient recruitment process, describe participant sampling and address if patients were from a consecutive series, and describe whether the clinicians were masked to the reference standard tests and whether the interpretation of the reference standard test was masked to the clinical examination components or overall clinical impression. The consideration of these and the other STARD items in clinical examination diagnostic research studies would improve the quality of investigations and strengthen conclusions reached by practicing clinicians. Conclusions The STARD statement provides a very useful framework for diagnostic accuracy studies. The group correctly anticipated that there would be nuances applicable to studies of the clinical examination. We offer guidance that should enhance their usefulness to investigators embarking on original studies of a patient’s history and physical examination. PMID:18347878
-
Ahrensberg, J M; Olesen, F; Hansen, R P; Schrøder, H; Vedsted, P
2013-01-01
Background: Early diagnosis of childhood cancer provides hope for better prognoses. Shorter diagnostic intervals (DI) in primary care require better knowledge of the association between presenting symptoms, interpretation of symptoms and the wording of the referral letter. Methods: A Danish nationwide population-based study. Data on 550 children aged <15 years with an incident cancer diagnosis (January 2007–December 2010) were collected through questionnaires to parents (response rate=69%) and general practitioners (GPs) (response rate=87%). The DI from the first presentation in general practice until diagnosis was categorised as short or long based on quartiles. Associations between variables and long DIs were assessed using logistic regression. Results: The GPs interpreted symptoms as ‘vague' in 25.4%, ‘serious' in 50.0% and ‘alarm' in 19.0% of cases. Symptom interpretation varied by cancer type (P<0.001) and was associated with the DI (P<0.001). Vomiting was associated with a shorter DI for central nervous system (CNS) tumours, and pain with a longer DI for leukaemia. Referral letter wording was associated with DI (P<0.001); the shortest DIs were observed when cancer suspicion was raised in the letter. Conclusion: The GPs play an important role in recognising early signs of childhood cancer as their symptom interpretation and referral wording have a profound impact on the diagnostic process. PMID:23449354
-
van Dijk, Joris D; van Dalen, Jorn A; Mouden, Mohamed; Ottervanger, Jan Paul; Knollema, Siert; Slump, Cornelis H; Jager, Pieter L
2018-04-01
Correction of motion has become feasible on cadmium-zinc-telluride (CZT)-based SPECT cameras during myocardial perfusion imaging (MPI). Our aim was to quantify the motion and to determine the value of automatic correction using commercially available software. We retrospectively included 83 consecutive patients who underwent stress-rest MPI CZT-SPECT and invasive fractional flow reserve (FFR) measurement. Eight-minute stress acquisitions were reformatted into 1.0- and 20-second bins to detect respiratory motion (RM) and patient motion (PM), respectively. RM and PM were quantified and scans were automatically corrected. Total perfusion deficit (TPD) and SPECT interpretation-normal, equivocal, or abnormal-were compared between the noncorrected and corrected scans. Scans with a changed SPECT interpretation were compared with FFR, the reference standard. Average RM was 2.5 ± 0.4 mm and maximal PM was 4.5 ± 1.3 mm. RM correction influenced the diagnostic outcomes in two patients based on TPD changes ≥7% and in nine patients based on changed visual interpretation. In only four of these patients, the changed SPECT interpretation corresponded with FFR measurements. Correction for PM did not influence the diagnostic outcomes. Respiratory motion and patient motion were small. Motion correction did not appear to improve the diagnostic outcome and, hence, the added value seems limited in MPI using CZT-based SPECT cameras.
-
Uneke, C J
2008-06-01
Malaria and typhoid fever still remain diseases of major public health importance in the tropics. Individuals in areas endemic for both the diseases are at substantial risk of contracting both these diseases, either concurrently or an acute infection superimposed on a chronic one. The objective of this report was to systematically review scientific data from studies conducted in the tropics on concurrent malaria and typhoid fever within the last two decades (1987-2007), to highlight the diagnostic challenges and the public health implications. Using the MedLine Entrez-PubMed search, relevant publications were identified for the review via the key words Malaria and Typhoid fever, which yielded 287 entries as of January 2008. Most of the studies reviewed expressed concern that poor diagnosis continues to hinder effective control of concurrent malaria and typhoid fever in the tropics due to: non-specific clinical presentation of the diseases; high prevalence of asymptomatic infections; lack of resources and insufficient access to trained health care providers and facilities; and widespread practice of self-treatment for clinically suspected malaria or typhoid fever. There were considerably higher rates of concurrent malaria and typhoid fever by Widal test compared to the bacteriological culture technique. Although culture technique remains the gold standard in typhoid fever diagnosis, Widal test is still of significant diagnostic value provided judicious interpretation of the test is made against a background of pertinent information. Malaria could be controlled through interventions to minimize human-vector contact, while improved personal hygiene, targeted vaccination campaigns and intensive community health education could help to control typhoid fever in the tropics.
-
Evaluating the Diagnostic Validity of a Facet-Based Formative Assessment System
ERIC Educational Resources Information Center
DeBarger, Angela Haydel; DiBello, Louis; Minstrell, Jim; Feng, Mingyu; Stout, William; Pellegrino, James; Haertel, Geneva; Harris, Christopher; Ructinger, Liliana
2011-01-01
This paper describes methods for an alignment study and psychometric analyses of a formative assessment system, Diagnoser Tools for physics. Diagnoser Tools begin with facet clusters as the interpretive framework for designing questions and instructional activities. Thus each question in the diagnostic assessments includes distractors that…
-
ECG Rhythm Analysis with Expert and Learner-Generated Schemas in Novice Learners
ERIC Educational Resources Information Center
Blissett, Sarah; Cavalcanti, Rodrigo; Sibbald, Matthew
2015-01-01
Although instruction using expert-generated schemas is associated with higher diagnostic performance, implementation is resource intensive. Learner-generated schemas are an alternative, but may be limited by increases in cognitive load. We compared expert- and learner-generated schemas for learning ECG rhythm interpretation on diagnostic accuracy,…
-
Benndorf, Matthias; Kotter, Elmar; Langer, Mathias; Herda, Christoph; Wu, Yirong; Burnside, Elizabeth S
2015-06-01
To develop and validate a decision support tool for mammographic mass lesions based on a standardized descriptor terminology (BI-RADS lexicon) to reduce variability of practice. We used separate training data (1,276 lesions, 138 malignant) and validation data (1,177 lesions, 175 malignant). We created naïve Bayes (NB) classifiers from the training data with tenfold cross-validation. Our "inclusive model" comprised BI-RADS categories, BI-RADS descriptors, and age as predictive variables; our "descriptor model" comprised BI-RADS descriptors and age. The resulting NB classifiers were applied to the validation data. We evaluated and compared classifier performance with ROC-analysis. In the training data, the inclusive model yields an AUC of 0.959; the descriptor model yields an AUC of 0.910 (P < 0.001). The inclusive model is superior to the clinical performance (BI-RADS categories alone, P < 0.001); the descriptor model performs similarly. When applied to the validation data, the inclusive model yields an AUC of 0.935; the descriptor model yields an AUC of 0.876 (P < 0.001). Again, the inclusive model is superior to the clinical performance (P < 0.001); the descriptor model performs similarly. We consider our classifier a step towards a more uniform interpretation of combinations of BI-RADS descriptors. We provide our classifier at www.ebm-radiology.com/nbmm/index.html . • We provide a decision support tool for mammographic masses at www.ebm-radiology.com/nbmm/index.html . • Our tool may reduce variability of practice in BI-RADS category assignment. • A formal analysis of BI-RADS descriptors may enhance radiologists' diagnostic performance.
-
Diagnostic Yield and Safety of Cerebellar and Brainstem Parenchymal Biopsy.
Tobin, W Oliver; Meyer, Fredric B; Keegan, B Mark
2015-12-01
We aimed to determine the diagnostic yield and safety of posterior fossa parenchymal biopsy. One-hundred-thirty-six patients who underwent 137 posterior fossa (brainstem or cerebellar) parenchymal biopsies at Mayo Clinic (Rochester, Minnesota, USA) between 1996 and 2009 were identified by chart review. Case histories; radiologic, surgical, and pathologic reports; and safety outcomes were assessed. Posterior fossa parenchymal biopsies were performed on 78 male and 58 female patients of median age 47 years (interquartile range 28-61). Preoperative clinical diagnosis in the majority of cases was of a malignant neoplasm. Glial neoplasm (51%) was the most common finding followed by lymphoma (7%) and neurosarcoidosis (7%). Normal tissue or nonspecific changes were observed in 28 cases (20%). Three deaths occurred: 2 at the time of biopsy (1%) and 1 due to underlying disease. All deaths occurred in patients who had a cerebellar biopsy. Transient neurologic deficits occurred in 15 patients (11%): worsening of presenting symptoms (4), cardiac arrhythmia (3), vertigo (2), diplopia (2), ataxia (3), seizure (1), decreased consciousness (1), and limb numbness (3). Sustained neurologic deficits occurred in 3 patients: fourth nerve palsy (1), hemiparesis (1), and facial numbness (1). The diagnostic yield of posterior fossa parenchymal biopsy in Mayo Clinic patients with diverse pathologies was 80%. The complication rate was 11% with the majority being transient, but 2 deaths were attributed to biopsy. Evaluation of the diagnostic yield and complication rate at individual neurosurgical centers is needed to determine generalizability of these results. Copyright © 2015 Elsevier Inc. All rights reserved.
-
Stavropoulos, Dimitri J; Merico, Daniele; Jobling, Rebekah; Bowdin, Sarah; Monfared, Nasim; Thiruvahindrapuram, Bhooma; Nalpathamkalam, Thomas; Pellecchia, Giovanna; Yuen, Ryan K C; Szego, Michael J; Hayeems, Robin Z; Shaul, Randi Zlotnik; Brudno, Michael; Girdea, Marta; Frey, Brendan; Alipanahi, Babak; Ahmed, Sohnee; Babul-Hirji, Riyana; Porras, Ramses Badilla; Carter, Melissa T; Chad, Lauren; Chaudhry, Ayeshah; Chitayat, David; Doust, Soghra Jougheh; Cytrynbaum, Cheryl; Dupuis, Lucie; Ejaz, Resham; Fishman, Leona; Guerin, Andrea; Hashemi, Bita; Helal, Mayada; Hewson, Stacy; Inbar-Feigenberg, Michal; Kannu, Peter; Karp, Natalya; Kim, Raymond H; Kronick, Jonathan; Liston, Eriskay; MacDonald, Heather; Mercimek-Mahmutoglu, Saadet; Mendoza-Londono, Roberto; Nasr, Enas; Nimmo, Graeme; Parkinson, Nicole; Quercia, Nada; Raiman, Julian; Roifman, Maian; Schulze, Andreas; Shugar, Andrea; Shuman, Cheryl; Sinajon, Pierre; Siriwardena, Komudi; Weksberg, Rosanna; Yoon, Grace; Carew, Chris; Erickson, Raith; Leach, Richard A; Klein, Robert; Ray, Peter N; Meyn, M Stephen; Scherer, Stephen W; Cohn, Ronald D; Marshall, Christian R
2016-01-01
The standard of care for first-tier clinical investigation of the aetiology of congenital malformations and neurodevelopmental disorders is chromosome microarray analysis (CMA) for copy-number variations (CNVs), often followed by gene(s)-specific sequencing searching for smaller insertion–deletions (indels) and single-nucleotide variant (SNV) mutations. Whole-genome sequencing (WGS) has the potential to capture all classes of genetic variation in one experiment; however, the diagnostic yield for mutation detection of WGS compared to CMA, and other tests, needs to be established. In a prospective study we utilised WGS and comprehensive medical annotation to assess 100 patients referred to a paediatric genetics service and compared the diagnostic yield versus standard genetic testing. WGS identified genetic variants meeting clinical diagnostic criteria in 34% of cases, representing a fourfold increase in diagnostic rate over CMA (8%; P value=1.42E−05) alone and more than twofold increase in CMA plus targeted gene sequencing (13%; P value=0.0009). WGS identified all rare clinically significant CNVs that were detected by CMA. In 26 patients, WGS revealed indel and missense mutations presenting in a dominant (63%) or a recessive (37%) manner. We found four subjects with mutations in at least two genes associated with distinct genetic disorders, including two cases harbouring a pathogenic CNV and SNV. When considering medically actionable secondary findings in addition to primary WGS findings, 38% of patients would benefit from genetic counselling. Clinical implementation of WGS as a primary test will provide a higher diagnostic yield than conventional genetic testing and potentially reduce the time required to reach a genetic diagnosis. PMID:28567303
-
Stavropoulos, Dimitri J; Merico, Daniele; Jobling, Rebekah; Bowdin, Sarah; Monfared, Nasim; Thiruvahindrapuram, Bhooma; Nalpathamkalam, Thomas; Pellecchia, Giovanna; Yuen, Ryan K C; Szego, Michael J; Hayeems, Robin Z; Shaul, Randi Zlotnik; Brudno, Michael; Girdea, Marta; Frey, Brendan; Alipanahi, Babak; Ahmed, Sohnee; Babul-Hirji, Riyana; Porras, Ramses Badilla; Carter, Melissa T; Chad, Lauren; Chaudhry, Ayeshah; Chitayat, David; Doust, Soghra Jougheh; Cytrynbaum, Cheryl; Dupuis, Lucie; Ejaz, Resham; Fishman, Leona; Guerin, Andrea; Hashemi, Bita; Helal, Mayada; Hewson, Stacy; Inbar-Feigenberg, Michal; Kannu, Peter; Karp, Natalya; Kim, Raymond; Kronick, Jonathan; Liston, Eriskay; MacDonald, Heather; Mercimek-Mahmutoglu, Saadet; Mendoza-Londono, Roberto; Nasr, Enas; Nimmo, Graeme; Parkinson, Nicole; Quercia, Nada; Raiman, Julian; Roifman, Maian; Schulze, Andreas; Shugar, Andrea; Shuman, Cheryl; Sinajon, Pierre; Siriwardena, Komudi; Weksberg, Rosanna; Yoon, Grace; Carew, Chris; Erickson, Raith; Leach, Richard A; Klein, Robert; Ray, Peter N; Meyn, M Stephen; Scherer, Stephen W; Cohn, Ronald D; Marshall, Christian R
2016-01-13
The standard of care for first-tier clinical investigation of the etiology of congenital malformations and neurodevelopmental disorders is chromosome microarray analysis (CMA) for copy number variations (CNVs), often followed by gene(s)-specific sequencing searching for smaller insertion-deletions (indels) and single nucleotide variant (SNV) mutations. Whole genome sequencing (WGS) has the potential to capture all classes of genetic variation in one experiment; however, the diagnostic yield for mutation detection of WGS compared to CMA, and other tests, needs to be established. In a prospective study we utilized WGS and comprehensive medical annotation to assess 100 patients referred to a paediatric genetics service and compared the diagnostic yield versus standard genetic testing. WGS identified genetic variants meeting clinical diagnostic criteria in 34% of cases, representing a 4-fold increase in diagnostic rate over CMA (8%) (p-value = 1.42e-05) alone and >2-fold increase in CMA plus targeted gene sequencing (13%) (p-value = 0.0009). WGS identified all rare clinically significant CNVs that were detected by CMA. In 26 patients, WGS revealed indel and missense mutations presenting in a dominant (63%) or a recessive (37%) manner. We found four subjects with mutations in at least two genes associated with distinct genetic disorders, including two cases harboring a pathogenic CNV and SNV. When considering medically actionable secondary findings in addition to primary WGS findings, 38% of patients would benefit from genetic counseling. Clinical implementation of WGS as a primary test will provide a higher diagnostic yield than conventional genetic testing and potentially reduce the time required to reach a genetic diagnosis.
-
Tribology behavior on scratch tests: Effects of yield strength
Feng, Biao
2017-03-07
In this paper, a three-dimensional (3D) scratch model is proposed to investigate the effects of yield strength of both coatings and substrates. With the help of combined Coulomb and plastic friction, the obtained results comprehensively interpret the experimental phenomena in most metals that with the growth of hardness after heat treatment the scratch friction coefficient (SFC) increases. This interpretation could not be done before. Scratch tests on the surface with or without the coating are discussed. Without the coating the SFC increases due to the decrease of the area with plastic slippage and/or the increase of friction stress during themore » increase of the yield strength in the material. With a softer substrate the friction stress decreases but the SFC increases, which is caused by the growth of the entire contact area and surface deformation. Conversely, with a stronger substrate the SFC decreases due to an intensified plastic slippage In conclusion, the obtained results pave a new way to understanding the effects of yield strength on scratch tests, interpret experimental phenomena, and should be helpful for an optimum design in experiments.« less
-
Tribology behavior on scratch tests: Effects of yield strength
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feng, Biao
In this paper, a three-dimensional (3D) scratch model is proposed to investigate the effects of yield strength of both coatings and substrates. With the help of combined Coulomb and plastic friction, the obtained results comprehensively interpret the experimental phenomena in most metals that with the growth of hardness after heat treatment the scratch friction coefficient (SFC) increases. This interpretation could not be done before. Scratch tests on the surface with or without the coating are discussed. Without the coating the SFC increases due to the decrease of the area with plastic slippage and/or the increase of friction stress during themore » increase of the yield strength in the material. With a softer substrate the friction stress decreases but the SFC increases, which is caused by the growth of the entire contact area and surface deformation. Conversely, with a stronger substrate the SFC decreases due to an intensified plastic slippage In conclusion, the obtained results pave a new way to understanding the effects of yield strength on scratch tests, interpret experimental phenomena, and should be helpful for an optimum design in experiments.« less
-
Suhanic, West; Crandall, Ian; Pennefather, Peter
2009-07-17
Deficits in clinical microbiology infrastructure exacerbate global infectious disease burdens. This paper examines how commodity computation, communication, and measurement products combined with open-source analysis and communication applications can be incorporated into laboratory medicine microbiology protocols. Those commodity components are all now sourceable globally. An informatics model is presented for guiding the use of low-cost commodity components and free software in the assembly of clinically useful and usable telemicrobiology workstations. The model incorporates two general principles: 1) collaborative diagnostics, where free and open communication and networking applications are used to link distributed collaborators for reciprocal assistance in organizing and interpreting digital diagnostic data; and 2) commodity engineering, which leverages globally available consumer electronics and open-source informatics applications, to build generic open systems that measure needed information in ways substantially equivalent to more complex proprietary systems. Routine microscopic examination of Giemsa and fluorescently stained blood smears for diagnosing malaria is used as an example to validate the model. The model is used as a constraint-based guide for the design, assembly, and testing of a functioning, open, and commoditized telemicroscopy system that supports distributed acquisition, exploration, analysis, interpretation, and reporting of digital microscopy images of stained malarial blood smears while also supporting remote diagnostic tracking, quality assessment and diagnostic process development. The open telemicroscopy workstation design and use-process described here can address clinical microbiology infrastructure deficits in an economically sound and sustainable manner. It can boost capacity to deal with comprehensive measurement of disease and care outcomes in individuals and groups in a distributed and collaborative fashion. The workstation enables local control over the creation and use of diagnostic data, while allowing for remote collaborative support of diagnostic data interpretation and tracking. It can enable global pooling of malaria disease information and the development of open, participatory, and adaptable laboratory medicine practices. The informatic model highlights how the larger issue of access to generic commoditized measurement, information processing, and communication technology in both high- and low-income countries can enable diagnostic services that are much less expensive, but substantially equivalent to those currently in use in high-income countries.
-
Sprague, Brian L; Arao, Robert F; Miglioretti, Diana L; Henderson, Louise M; Buist, Diana S M; Onega, Tracy; Rauscher, Garth H; Lee, Janie M; Tosteson, Anna N A; Kerlikowske, Karla; Lehman, Constance D
2017-04-01
Purpose To establish contemporary performance benchmarks for diagnostic digital mammography with use of recent data from the Breast Cancer Surveillance Consortium (BCSC). Materials and Methods Institutional review board approval was obtained for active or passive consenting processes or to obtain a waiver of consent to enroll participants, link data, and perform analyses. Data were obtained from six BCSC registries (418 radiologists, 92 radiology facilities). Mammogram indication and assessments were prospectively collected for women undergoing diagnostic digital mammography and linked with cancer diagnoses from state cancer registries. The study included 401 548 examinations conducted from 2007 to 2013 in 265 360 women. Results Overall diagnostic performance measures were as follows: cancer detection rate, 34.7 per 1000 (95% confidence interval [CI]: 34.1, 35.2); abnormal interpretation rate, 12.6% (95% CI: 12.5%, 12.7%); positive predictive value (PPV) of a biopsy recommendation (PPV 2 ), 27.5% (95% CI: 27.1%, 27.9%); PPV of biopsies performed (PPV 3 ), 30.4% (95% CI: 29.9%, 30.9%); false-negative rate, 4.8 per 1000 (95% CI: 4.6, 5.0); sensitivity, 87.8% (95% CI: 87.3%, 88.4%); and specificity, 90.5% (95% CI: 90.4%, 90.6%). Among cancers detected, 63.4% were stage 0 or 1 cancers, 45.6% were minimal cancers, the mean size of invasive cancers was 21.2 mm, and 69.6% of invasive cancers were node negative. Performance metrics varied widely across diagnostic indications, with cancer detection rate (64.5 per 1000) and abnormal interpretation rate (18.7%) highest for diagnostic mammograms obtained to evaluate a breast problem with a lump. Compared with performance during the screen-film mammography era, diagnostic digital performance showed increased abnormal interpretation and cancer detection rates and decreasing PPVs, with less than 70% of radiologists within acceptable ranges for PPV 2 and PPV 3 . Conclusion These performance measures can serve as national benchmarks that may help transform the marked variation in radiologists' diagnostic performance into targeted quality improvement efforts. © RSNA, 2017 Online supplemental material is available for this article.
-
Integrated Artificial Intelligence Approaches for Disease Diagnostics.
Vashistha, Rajat; Chhabra, Deepak; Shukla, Pratyoosh
2018-06-01
Mechanocomputational techniques in conjunction with artificial intelligence (AI) are revolutionizing the interpretations of the crucial information from the medical data and converting it into optimized and organized information for diagnostics. It is possible due to valuable perfection in artificial intelligence, computer aided diagnostics, virtual assistant, robotic surgery, augmented reality and genome editing (based on AI) technologies. Such techniques are serving as the products for diagnosing emerging microbial or non microbial diseases. This article represents a combinatory approach of using such approaches and providing therapeutic solutions towards utilizing these techniques in disease diagnostics.
-
45 CFR 170.314 - 2014 Edition electronic health record certification criteria.
Code of Federal Regulations, 2012 CFR
2012-10-01
... specified at § 170.207(h). (12) Image results. Electronically indicate to a user the availability of a patient's images and narrative interpretations (relating to the radiographic or other diagnostic test(s)) and enable electronic access to such images and narrative interpretations. (13) Family health history...
-
45 CFR 170.314 - 2014 Edition electronic health record certification criteria.
Code of Federal Regulations, 2013 CFR
2013-10-01
... specified at § 170.207(h). (12) Image results. Electronically indicate to a user the availability of a patient's images and narrative interpretations (relating to the radiographic or other diagnostic test(s)) and enable electronic access to such images and narrative interpretations. (13) Family health history...
-
Nonportable computed radiography of the chest--radiologists' acceptance
NASA Astrophysics Data System (ADS)
Gennari, Rose C.; Gur, David; Miketic, Linda M.; Campbell, William L.; Oliver, James H., III; Plunkett, Michael B.
1994-04-01
Following a large ROC study to assess diagnostic accuracy of PA chest computed radiography (CR) images displayed in a variety of formats, we asked nine experienced radiologists to subjectively assess their acceptance of and preferences for display modes in primary diagnosis of erect PA chest images. Our results indicate that radiologists felt somewhat less comfortable interpreting CR images displayed on either laser-printed films or workstations as compared to conventional films. The use of four minified images were thought to somewhat decrease diagnostic confidence, as well as to increase the time of interpretation. The reverse mode (black bone) images increased radiologists' confidence level in the detection of soft tissue abnormalities.
-
Smith, Hadley Stevens; Swint, J Michael; Lalani, Seema R; Yamal, Jose-Miguel; de Oliveira Otto, Marcia C; Castellanos, Stephan; Taylor, Amy; Lee, Brendan H; Russell, Heidi V
2018-05-14
Availability of clinical genomic sequencing (CGS) has generated questions about the value of genome and exome sequencing as a diagnostic tool. Analysis of reported CGS application can inform uptake and direct further research. This scoping literature review aims to synthesize evidence on the clinical and economic impact of CGS. PubMed, Embase, and Cochrane were searched for peer-reviewed articles published between 2009 and 2017 on diagnostic CGS for infant and pediatric patients. Articles were classified according to sample size and whether economic evaluation was a primary research objective. Data on patient characteristics, clinical setting, and outcomes were extracted and narratively synthesized. Of 171 included articles, 131 were case reports, 40 were aggregate analyses, and 4 had a primary economic evaluation aim. Diagnostic yield was the only consistently reported outcome. Median diagnostic yield in aggregate analyses was 33.2% but varied by broad clinical categories and test type. Reported CGS use has rapidly increased and spans diverse clinical settings and patient phenotypes. Economic evaluations support the cost-saving potential of diagnostic CGS. Multidisciplinary implementation research, including more robust outcome measurement and economic evaluation, is needed to demonstrate clinical utility and cost-effectiveness of CGS.
-
Factor regression for interpreting genotype-environment interaction in bread-wheat trials.
Baril, C P
1992-05-01
The French INRA wheat (Triticum aestivum L. em Thell.) breeding program is based on multilocation trials to produce high-yielding, adapted lines for a wide range of environments. Differential genotypic responses to variable environment conditions limit the accuracy of yield estimations. Factor regression was used to partition the genotype-environment (GE) interaction into four biologically interpretable terms. Yield data were analyzed from 34 wheat genotypes grown in four environments using 12 auxiliary agronomic traits as genotypic and environmental covariates. Most of the GE interaction (91%) was explained by the combination of only three traits: 1,000-kernel weight, lodging susceptibility and spike length. These traits are easily measured in breeding programs, therefore factor regression model can provide a convenient and useful prediction method of yield.
-
NASA Astrophysics Data System (ADS)
Cherdizov, R. K.; Fursov, F. I.; Kokshenev, V. A.; Kurmaev, N. E.; Labetsky, A. Yu; Ratakhin, N. A.; Shishlov, A. V.; Cikhardt, J.; Cikhardtova, B.; Klir, D.; Kravarik, J.; Kubes, P.; Rezac, K.; Dudkin, G. N.; Garapatsky, A. A.; Padalko, V. N.; Varlachev, V. A.
2017-05-01
The Z-pinch experiments with deuterium gas-puff surrounded by an outer plasma shell were carried out on the GIT-12 generator (Tomsk, Russia) at currents of 2 MA. The plasma shell consisting of hydrogen and carbon ions was formed by 48 plasma guns. The deuterium gas-puff was created by a fast electromagnetic valve. This configuration provides an efficient mode of the neutron production in DD reaction, and the neutron yield reaches a value above 1012 neutrons per shot. Neutron diagnostics included scintillation TOF detectors for determination of the neutron energy spectrum, bubble detectors BD-PND, a silver activation detector, and several activation samples for determination of the neutron yield analysed by a Sodium Iodide (NaI) and a high-purity Germanium (HPGe) detectors. Using this neutron diagnostic complex, we measured the total neutron yield and amount of high-energy neutrons.
-
Using pattern analysis methods to do fast detection of manufacturing pattern failures
NASA Astrophysics Data System (ADS)
Zhao, Evan; Wang, Jessie; Sun, Mason; Wang, Jeff; Zhang, Yifan; Sweis, Jason; Lai, Ya-Chieh; Ding, Hua
2016-03-01
At the advanced technology node, logic design has become extremely complex and is getting more challenging as the pattern geometry size decreases. The small sizes of layout patterns are becoming very sensitive to process variations. Meanwhile, the high pressure of yield ramp is always there due to time-to-market competition. The company that achieves patterning maturity earlier than others will have a great advantage and a better chance to realize maximum profit margins. For debugging silicon failures, DFT diagnostics can identify which nets or cells caused the yield loss. But normally, a long time period is needed with many resources to identify which failures are due to one common layout pattern or structure. This paper will present a new yield diagnostic flow, based on preliminary EFA results, to show how pattern analysis can more efficiently detect pattern related systematic defects. Increased visibility on design pattern related failures also allows more precise yield loss estimation.
-
Schönhals, E M; Ortega, F; Barandalla, L; Aragones, A; Ruiz de Galarreta, J I; Liao, J-C; Sanetomo, R; Walkemeier, B; Tacke, E; Ritter, E; Gebhardt, C
2016-04-01
SNPs in candidate genes Pain - 1, InvCD141 (invertases), SSIV (starch synthase), StCDF1 (transcription factor), LapN (leucine aminopeptidase), and cytoplasm type are associated with potato tuber yield, starch content and/or starch yield. Tuber yield (TY), starch content (TSC), and starch yield (TSY) are complex characters of high importance for the potato crop in general and for industrial starch production in particular. DNA markers associated with superior alleles of genes that control the natural variation of TY, TSC, and TSY could increase precision and speed of breeding new cultivars optimized for potato starch production. Diagnostic DNA markers are identified by association mapping in populations of tetraploid potato varieties and advanced breeding clones. A novel association mapping population of 282 genotypes including varieties, breeding clones and Andean landraces was assembled and field evaluated in Northern Spain for TY, TSC, TSY, tuber number (TN) and tuber weight (TW). The landraces had lower mean values of TY, TW, TN, and TSY. The population was genotyped for 183 microsatellite alleles, 221 single nucleotide polymorphisms (SNPs) in fourteen candidate genes and eight known diagnostic markers for TSC and TSY. Association test statistics including kinship and population structure reproduced five known marker-trait associations of candidate genes and discovered new ones, particularly for tuber yield and starch yield. The inclusion of landraces increased the number of detected marker-trait associations. Integration of the present association mapping results with previous QTL linkage mapping studies for TY, TSC, TSY, TW, TN, and tuberization revealed some hot spots of QTL for these traits in the potato genome. The genomic positions of markers linked or associated with QTL for complex tuber traits suggest high multiplicity and genome wide distribution of the underlying genes.
-
Heuristics and Cognitive Error in Medical Imaging.
Itri, Jason N; Patel, Sohil H
2018-05-01
The field of cognitive science has provided important insights into mental processes underlying the interpretation of imaging examinations. Despite these insights, diagnostic error remains a major obstacle in the goal to improve quality in radiology. In this article, we describe several types of cognitive bias that lead to diagnostic errors in imaging and discuss approaches to mitigate cognitive biases and diagnostic error. Radiologists rely on heuristic principles to reduce complex tasks of assessing probabilities and predicting values into simpler judgmental operations. These mental shortcuts allow rapid problem solving based on assumptions and past experiences. Heuristics used in the interpretation of imaging studies are generally helpful but can sometimes result in cognitive biases that lead to significant errors. An understanding of the causes of cognitive biases can lead to the development of educational content and systematic improvements that mitigate errors and improve the quality of care provided by radiologists.
-
Hahn, K D; Cooper, G W; Ruiz, C L; Fehl, D L; Chandler, G A; Knapp, P F; Leeper, R J; Nelson, A J; Smelser, R M; Torres, J A
2014-04-01
We present a general methodology to determine the diagnostic sensitivity that is directly applicable to neutron-activation diagnostics fielded on a wide variety of neutron-producing experiments, which include inertial-confinement fusion (ICF), dense plasma focus, and ion beam-driven concepts. This approach includes a combination of several effects: (1) non-isotropic neutron emission; (2) the 1/r(2) decrease in neutron fluence in the activation material; (3) the spatially distributed neutron scattering, attenuation, and energy losses due to the fielding environment and activation material itself; and (4) temporally varying neutron emission. As an example, we describe the copper-activation diagnostic used to measure secondary deuterium-tritium fusion-neutron yields on ICF experiments conducted on the pulsed-power Z Accelerator at Sandia National Laboratories. Using this methodology along with results from absolute calibrations and Monte Carlo simulations, we find that for the diagnostic configuration on Z, the diagnostic sensitivity is 0.037% ± 17% counts/neutron per cm(2) and is ∼ 40% less sensitive than it would be in an ideal geometry due to neutron attenuation, scattering, and energy-loss effects.
-
ERIC Educational Resources Information Center
Cui, Ying; Gierl, Mark; Guo, Qi
2016-01-01
The purpose of the current investigation was to describe how the artificial neural networks (ANNs) can be used to interpret student performance on cognitive diagnostic assessments (CDAs) and evaluate the performances of ANNs using simulation results. CDAs are designed to measure student performance on problem-solving tasks and provide useful…
-
Diagnostic Competence of Primary School Mathematics Teachers during Classroom Situations
ERIC Educational Resources Information Center
Hoth, Jessica; Döhrmann, Martina; Kaiser, Gabriele; Busse, Andreas; König, Johannes; Blömeke, Sigrid
2016-01-01
One of the main challenges for teachers during teaching in class is the diagnosis of students' learning and thinking processes. For this purpose, teachers must perceive relevant information, they need to interpret this information and finally, they need to respond and select suitable opportunities to learn. In this paper, diagnostic processes in…
-
Forceps biopsy and suction catheter for sampling in pulmonary nodules and infiltrates.
Peschke, Antje; Wiedemann, Bärbel; Höffken, Gert; Koschel, Dirk
2012-06-01
Transbronchial lung biopsy with forceps is a standard procedure in bronchoscopic tissue sampling. Suction catheter aspiration is another technique, but it is not widely known and almost no data exist regarding its diagnostic efficiency. 272 patients were included in a prospective and randomised study between February 2007 and October 2009. All were referred for bronchoscopic evaluation of pulmonary nodules/masses or infiltrates. We compared the diagnostic yield of forceps biopsy and suction catheter aspiration for a definite diagnosis and looked at whether such a diagnosis depends on the underlying pulmonary change. All patients underwent bronchoscopy with forceps biopsy and catheter aspiration. A definitive diagnosis was reached in a total of 183 (67.3%) patients, with catheter aspiration in 140 (51.5%) patients and with forceps biopsy in 136 (50.0%) patients. In 90 (33.1%) patients, a definite diagnosis could only be reached with the combination of both techniques. The diagnostic yield of forceps biopsy was better than catheter aspiration in infiltrates (p = 0.027), but was no different in nodules or masses (p = 0.09). Suction catheter aspiration is a useful technique of bronchoscopic tissue sampling. The combination of catheter aspiration and forceps biopsy results in a higher diagnostic yield than either method used alone.
-
Frameless robotically targeted stereotactic brain biopsy: feasibility, diagnostic yield, and safety.
Bekelis, Kimon; Radwan, Tarek A; Desai, Atman; Roberts, David W
2012-05-01
Frameless stereotactic brain biopsy has become an established procedure in many neurosurgical centers worldwide. Robotic modifications of image-guided frameless stereotaxy hold promise for making these procedures safer, more effective, and more efficient. The authors hypothesized that robotic brain biopsy is a safe, accurate procedure, with a high diagnostic yield and a safety profile comparable to other stereotactic biopsy methods. This retrospective study included 41 patients undergoing frameless stereotactic brain biopsy of lesions (mean size 2.9 cm) for diagnostic purposes. All patients underwent image-guided, robotic biopsy in which the SurgiScope system was used in conjunction with scalp fiducial markers and a preoperatively selected target and trajectory. Forty-five procedures, with 50 supratentorial targets selected, were performed. The mean operative time was 44.6 minutes for the robotic biopsy procedures. This decreased over the second half of the study by 37%, from 54.7 to 34.5 minutes (p < 0.025). The diagnostic yield was 97.8% per procedure, with a second procedure being diagnostic in the single nondiagnostic case. Complications included one transient worsening of a preexisting deficit (2%) and another deficit that was permanent (2%). There were no infections. Robotic biopsy involving a preselected target and trajectory is safe, accurate, efficient, and comparable to other procedures employing either frame-based stereotaxy or frameless, nonrobotic stereotaxy. It permits biopsy in all patients, including those with small target lesions. Robotic biopsy planning facilitates careful preoperative study and optimization of needle trajectory to avoid sulcal vessels, bridging veins, and ventricular penetration.
-
Singh, Neha; Pati, Hara Prasad P; Tyagi, Seema; Deka, Roopam; Sharma, Rahul; Saxena, Renu
2016-07-01
Flowcytometry has an essential role in the diagnosis and classification of acute leukemias. However, there exists a great degree of inter-laboratory variability on issues like panel selection, antibody combinations, gating strategies, fluorochromes, and clonal selection. The primary aim of this study was to derive a minimal panel of antibodies and evaluate its diagnostic usefulness in acute leukemias by flowcytometry by using the detailed immune-phenotype of different lineage-specific or non-specific markers. This prospective observational study involved 400 newly diagnosed cases of acute leukemias. Bone marrow aspirate samples were subjected to morphological evaluation, cytogenetics and flow cytometric immunophenotyping. A minimal panel of eight antibodies comprising of CD45/CD34/CD19/MPO/cytoCD3/CD64/CD117/CD79a was derived by applying different permutations and combinations with a diagnostic yield of 97.5%. The minimal panel was further validated by testing in an independent cohort of patients with similar demographic characteristics, where it showed a high diagnostic yield of 98% in comparison with the screening panels proposed by other recently published studies. It may be concluded that the diagnostic performance of the eight antibody panel is better than most other panels used across the different laboratories in terms of yield, number of antibodies used and the scientific approach used to derive and validate the results and so henceforth may be applied in any setting with limited resources for better diagnostic accuracy.
-
Clinical Utility of Blood Cell Histogram Interpretation
Bhagya, S.; Majeed, Abdul
2017-01-01
An automated haematology analyser provides blood cell histograms by plotting the sizes of different blood cells on X-axis and their relative number on Y-axis. Histogram interpretation needs careful analysis of Red Blood Cell (RBC), White Blood Cell (WBC) and platelet distribution curves. Histogram analysis is often a neglected part of the automated haemogram which if interpreted well, has significant potential to provide diagnostically relevant information even before higher level investigations are ordered. PMID:29207767
-
Clinical Utility of Blood Cell Histogram Interpretation.
Thomas, E T Arun; Bhagya, S; Majeed, Abdul
2017-09-01
An automated haematology analyser provides blood cell histograms by plotting the sizes of different blood cells on X-axis and their relative number on Y-axis. Histogram interpretation needs careful analysis of Red Blood Cell (RBC), White Blood Cell (WBC) and platelet distribution curves. Histogram analysis is often a neglected part of the automated haemogram which if interpreted well, has significant potential to provide diagnostically relevant information even before higher level investigations are ordered.
-
Marsh, Jessecae K; Burke, Christopher T; De Los Reyes, Andres
2016-02-01
How people interpret a mental disorder symptom has been shown to depend on the contextual life factors surrounding its presentation. Specifically, people are more likely to judge a symptom as clinically relevant if that symptom presents in a high-risk environment (e.g., child associates with deviant peers) relative to a low-risk environment (e.g., child associates with normative peer group). Importantly, not all symptoms are influenced by context to the same extent, and there is low agreement across people as to how this influence manifests. In this paper, we explore what factors predict the extent to which clinicians and laypeople interpret mental disorder symptoms as a function of diagnosis-congruent versus incongruent contextual information. We tested the impact of 2 statistical factors (prevalence and diagnosticity) and 2 more intuitive factors (diagnostic importance and abnormality) on the degree to which a symptom is interpreted differently in different contexts. Clinicians' impressions of the diagnosticity and importance of a symptom evidenced a curvilinear relationship with the use of context, with extremely important and unimportant as well as extremely diagnostic and nondiagnostic symptoms being less influenced by context. Laypeople showed a similar curvilinear relation between diagnosticity judgments and context effects. Additionally, clinicians showed a linear relationship between abnormality judgments and context use, with extremely abnormal symptoms being influenced less by context, whereas laypeople showed a curvilinear relationship between symptom abnormality and context use, with extremely abnormal and normal symptoms being influenced the most by context. We discuss implications of these findings for clinical diagnosis. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leonard Angello
2005-09-30
Power generators are concerned with the maintenance costs associated with the advanced turbines that they are purchasing. Since these machines do not have fully established Operation and Maintenance (O&M) track records, power generators face financial risk due to uncertain future maintenance costs. This risk is of particular concern, as the electricity industry transitions to a competitive business environment in which unexpected O&M costs cannot be passed through to consumers. These concerns have accelerated the need for intelligent software-based diagnostic systems that can monitor the health of a combustion turbine in real time and provide valuable information on the machine's performancemore » to its owner/operators. EPRI, Impact Technologies, Boyce Engineering, and Progress Energy have teamed to develop a suite of intelligent software tools integrated with a diagnostic monitoring platform that, in real time, interpret data to assess the 'total health' of combustion turbines. The 'Combustion Turbine Health Management System' (CTHMS) will consist of a series of 'Dynamic Link Library' (DLL) programs residing on a diagnostic monitoring platform that accepts turbine health data from existing monitoring instrumentation. CTHMS interprets sensor and instrument outputs, correlates them to a machine's condition, provide interpretative analyses, project servicing intervals, and estimate remaining component life. In addition, the CTHMS enables real-time anomaly detection and diagnostics of performance and mechanical faults, enabling power producers to more accurately predict critical component remaining useful life and turbine degradation.« less
-
Swartz, Jordan; Koziatek, Christian; Theobald, Jason; Smith, Silas; Iturrate, Eduardo
2017-05-01
Testing for venous thromboembolism (VTE) is associated with cost and risk to patients (e.g. radiation). To assess the appropriateness of imaging utilization at the provider level, it is important to know that provider's diagnostic yield (percentage of tests positive for the diagnostic entity of interest). However, determining diagnostic yield typically requires either time-consuming, manual review of radiology reports or the use of complex and/or proprietary natural language processing software. The objectives of this study were twofold: 1) to develop and implement a simple, user-configurable, and open-source natural language processing tool to classify radiology reports with high accuracy and 2) to use the results of the tool to design a provider-specific VTE imaging dashboard, consisting of both utilization rate and diagnostic yield. Two physicians reviewed a training set of 400 lower extremity ultrasound (UTZ) and computed tomography pulmonary angiogram (CTPA) reports to understand the language used in VTE-positive and VTE-negative reports. The insights from this review informed the arguments to the five modifiable parameters of the NLP tool. A validation set of 2,000 studies was then independently classified by the reviewers and by the tool; the classifications were compared and the performance of the tool was calculated. The tool was highly accurate in classifying the presence and absence of VTE for both the UTZ (sensitivity 95.7%; 95% CI 91.5-99.8, specificity 100%; 95% CI 100-100) and CTPA reports (sensitivity 97.1%; 95% CI 94.3-99.9, specificity 98.6%; 95% CI 97.8-99.4). The diagnostic yield was then calculated at the individual provider level and the imaging dashboard was created. We have created a novel NLP tool designed for users without a background in computer programming, which has been used to classify venous thromboembolism reports with a high degree of accuracy. The tool is open-source and available for download at http://iturrate.com/simpleNLP. Results obtained using this tool can be applied to enhance quality by presenting information about utilization and yield to providers via an imaging dashboard. Copyright © 2017 Elsevier B.V. All rights reserved.
-
Discriminant Validity of the WISC-IV Culture-Language Interpretive Matrix
ERIC Educational Resources Information Center
Styck, Kara M.; Watkins, Marley W.
2014-01-01
The Culture-Language Interpretive Matrix (C-LIM) was developed to help practitioners determine the validity of test scores obtained from students who are culturally and linguistically different from the normative group of a test. The present study used an idiographic approach to investigate the diagnostic utility of the C-LIM for the Wechsler…
-
ERIC Educational Resources Information Center
Amir, Nader; Taylor, Charles T.
2012-01-01
Objective: To examine the efficacy of a multisession computerized interpretation modification program (IMP) in the treatment of generalized social anxiety disorder (GSAD). Method: The sample comprised 49 individuals meeting diagnostic criteria for GSAD who were enrolled in a randomized, double-blind placebo-controlled trial comparing IMP (n = 23)…
-
Advances in diagnostic interventional pulmonology
Al-Zubaidi, Nassar; Soubani, Ayman O.
2015-01-01
The recent advances in diagnostic pulmonary procedures have revolutionized the evaluation of abnormal thoracic findings including lung nodules and masses, mediastinal lymphadenopathy, and pleural diseases. Bronchoscopies with endobronchial ultrasonography and electromagnetic navigation are examples of new technology that has significantly improved the specificity and sensitivity of these procedures in diagnosis and staging of lung cancer without the need for more invasive procedures. This report describes the different diagnostic pulmonary interventions providing a description of the procedures, their indications, diagnostic yield and drawback. PMID:26229756
-
Interobserver reproducibility in pathologist interpretation of columnar-lined esophagus.
Mastracci, Luca; Piol, Nataniele; Molinaro, Luca; Pitto, Francesca; Tinelli, Carmine; De Silvestri, Annalisa; Fiocca, Roberto; Grillo, Federica
2016-02-01
Confirmation of endoscopically suspected esophageal metaplasia (ESEM) requires histology, but confusion in the histological definition of columnar-lined esophagus (CLE) is a longstanding problem. The aim of this study is to evaluate interpathologist variability in the interpretation of CLE. Thirty pathologists were invited to review three ten-case sets of CLE biopsies. In the first set, the cases were provided with descriptive endoscopy only; in the second and the third sets, ESEM extent using Prague criteria was provided. Moreover, participants were required to refer to a diagnostic chart for evaluation of the third set. Agreement was statistically assessed using Randolph's free-marginal multirater kappa. While substantial agreement in recognizing columnar epithelium (K = 0.76) was recorded, the overall concordance in clinico-pathological diagnosis was low (K = 0.38). The overall concordance rate improved from the first (K = 0.27) to the second (K = 0.40) and third step (K = 0.46). Agreement was substantial when diagnosing Barrett's esophagus (BE) with intestinal metaplasia or inlet patch (K = 0.65 and K = 0.89), respectively, in the third step, while major problems in interpretation of CLE were observed when only cardia/cardia-oxyntic atrophic-type epithelium was present (K = 0.05-0.29). In conclusion, precise endoscopic description and the use of a diagnostic chart increased consistency in CLE interpretation of esophageal biopsies. Agreement was substantial for some diagnostic categories (BE with intestinal metaplasia and inlet patch) with a well-defined clinical profile. Interpretation of cases with cardia/cardia-oxyntic atrophic-type epithelium, with or without ESEM, was least consistent, which reflects lack of clarity of definition and results in variable management of this entity.
-
Cryobiopsy: Should This Be Used in Place of Endobronchial Forceps Biopsies?
Rubio, Edmundo R.; le, Susanti R.; Whatley, Ralph E.; Boyd, Michael B.
2013-01-01
Forceps biopsies of airway lesions have variable yields. The yield increases when combining techniques in order to collect more material. With the use of cryotherapy probes (cryobiopsy) larger specimens can be obtained, resulting in an increase in the diagnostic yield. However, the utility and safety of cryobiopsy with all types of lesions, including flat mucosal lesions, is not established. Aims. Demonstrate the utility/safety of cryobiopsy versus forceps biopsy to sample exophytic and flat airway lesions. Settings and Design. Teaching hospital-based retrospective analysis. Methods. Retrospective analysis of patients undergoing cryobiopsies (singly or combined with forceps biopsies) from August 2008 through August 2010. Statistical Analysis. Wilcoxon signed-rank test. Results. The comparative analysis of 22 patients with cryobiopsy and forceps biopsy of the same lesion showed the mean volumes of material obtained with cryobiopsy were significantly larger (0.696 cm3 versus 0.0373 cm3, P = 0.0014). Of 31 cryobiopsies performed, one had minor bleeding. Cryopbiopsy allowed sampling of exophytic and flat lesions that were located centrally or distally. Cryobiopsies were shown to be safe, free of artifact, and provided a diagnostic yield of 96.77%. Conclusions. Cryobiopsy allows safe sampling of exophytic and flat airway lesions, with larger specimens, excellent tissue preservation and high diagnostic accuracy. PMID:24066296
-
Hormann, Wymke; Hahn, Melanie; Gerlach, Stefan; Hochstrate, Nicola; Affeldt, Kai; Giesen, Joyce; Fechner, Kai; Damoiseaux, Jan G M C
2017-11-27
Antibodies directed against dsDNA are a highly specific diagnostic marker for the presence of systemic lupus erythematosus and of particular importance in its diagnosis. To assess anti-dsDNA antibodies, the Crithidia luciliae-based indirect immunofluorescence test (CLIFT) is one of the assays considered to be the best choice. To overcome the drawback of subjective result interpretation that inheres indirect immunofluorescence assays in general, automated systems have been introduced into the market during the last years. Among these systems is the EUROPattern Suite, an advanced automated fluorescence microscope equipped with different software packages, capable of automated pattern interpretation and result suggestion for ANA, ANCA and CLIFT analysis. We analyzed the performance of the EUROPattern Suite with its automated fluorescence interpretation for CLIFT in a routine setting, reflecting the everyday life of a diagnostic laboratory. Three hundred and twelve consecutive samples were collected, sent to the Central Diagnostic Laboratory of the Maastricht University Medical Centre with a request for anti-dsDNA analysis over a period of 7 months. Agreement between EUROPattern assay analysis and the visual read was 93.3%. Sensitivity and specificity were 94.1% and 93.2%, respectively. The EUROPattern Suite performed reliably and greatly supported result interpretation. Automated image acquisition is readily performed and automated image classification gives a reliable recommendation for assay evaluation to the operator. The EUROPattern Suite optimizes workflow and contributes to standardization between different operators or laboratories.
-
Influence of diagnostic criteria on the interpretation of adrenal vein sampling.
Lethielleux, Gaëlle; Amar, Laurence; Raynaud, Alain; Plouin, Pierre-François; Steichen, Olivier
2015-04-01
Guidelines promote the use of adrenal vein sampling (AVS) to document lateralized aldosterone hypersecretion in primary aldosteronism. However, there are large discrepancies between institutions in the criteria used to interpret its results. This study evaluates the consequences of these differences on the classification and management of patients. The results of all 537 AVS procedures performed between January 2001 and July 2010 in our institution were interpreted with 4 diagnostic criteria used in experienced institutions where AVS is performed without cosyntropin (Brisbane, Padua, Paris, and Turin) and with criteria proposed by a recent consensus statement. AVS procedures were classified as unsuccessful, lateralized, or not lateralized according to each set of criteria. Almost 5× more AVS procedures were classified as unsuccessful with the strictest criteria than with the least strict criteria (18% versus 4%, respectively). Similarly, over 2× more AVS procedures were classified as lateralized with the least stringent criteria than with the most stringent criteria (60% versus 26%, respectively). Multiple samples were available from ≥1 side for 155 AVS procedures. These procedures were classified differently by ≥2 right-left sample pairs in 12% to 20% of cases. Thus, different sets of criteria used to interpret AVS in experienced institutions translate into heterogeneous classifications and hence management decisions, for patients with primary aldosteronism. Defining the most appropriate procedures and diagnostic criteria is needed for AVS to achieve optimal performance and fully justify its status as a gold standard. © 2015 American Heart Association, Inc.
-
Feasibility of Image-Guided Transthoracic Core Needle Biopsy in the BATTLE Lung Trial
Tam, Alda L.; Kim, Edward S.; Lee, J. Jack; Ensor, Joe E.; Hicks, Marshall E.; Tang, Ximing; Blumenschein, George R.; Alden, Christine M.; Erasmus, Jeremy J.; Tsao, Anne; Lippman, Scott M.; Hong, Waun K.; Wistuba, Ignacio I.; Gupta, Sanjay
2013-01-01
Purpose As therapy for non-small cell lung cancer (NSCLC) patients becomes more personalized, additional tissue in the form of core needle biopsies (CNBs) for biomarker analysis is increasingly required for determining appropriate treatment and for enrollment into clinical trials. We report our experience with small-caliber percutaneous transthoracic (PT) CNBs for the evaluation of multiple molecular biomarkers in BATTLE (Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination), a personalized, targeted therapy NSCLC clinical trial. Methods The medical records of patients who underwent PTCNB for consideration of enrollment in BATTLE, were reviewed for diagnostic yield of 11 predetermined molecular markers, and procedural complications. Univariate and multivariate analyses of factors related to patient and lesion characteristics were performed to determine possible influences on diagnostic yield. Results One hundred and seventy PTCNBs were performed using 20-gauge biopsy needles in 151 NSCLC patients screened for the trial. 82.9% of the biopsy specimens were found to have adequate tumor tissue for analysis of the required biomarkers. On multivariate analysis, metastatic lesions were 5.4 times more likely to yield diagnostic tissue as compared to primary tumors (p = 0.0079). Pneumothorax and chest tube insertion rates were 15.3% and 9.4%, respectively. Conclusions Image-guided 20-gauge PTCNB is safe and provides adequate tissue for analysis of multiple biomarkers in the majority of patients being considered for enrollment into a personalized, targeted therapy NSCLC clinical trial. Metastatic lesions are more likely to yield diagnostic tissue as compared to primary tumors. PMID:23442309
-
Böcker, Ulrich; Dinter, Dietmar; Litterer, Caroline; Hummel, Frank; Knebel, Phillip; Franke, Andreas; Weiss, Christel; Singer, Manfred V; Löhr, J-Matthias
2010-04-01
New technology has considerably advanced the diagnosis of small-bowel pathology. However, its significance in clinical algorithms has not yet been fully assessed. The aim of the present analysis was to compare the diagnostic utility and yield of video-capsule enteroscopy (VCE) to that of magnetic resonance imaging (MRI) in patients with suspected or established Crohn's disease (Group I), obscure gastrointestinal blood loss (Group II), or suspected tumors (Group III). Forty-six out of 182 patients who underwent both modalities were included: 21 in Group I, 20 in Group II, and five in Group III. Pathology was assessed in three predetermined sections of the small bowel (upper, middle, and lower). The McNemar and Wilcoxon tests were used for statistical analysis. In Group I, lesions were found by VCE in nine of the 21 patients and by MRI in six. In five patients, both modalities showed pathology. In Group II, pathological changes were detected in 11 of the 20 patients by VCE and in eight patients by MRI. In five cases, pathology was found with both modalities. In Group III, neither modality showed small-bowel pathology. For the patient groups combined, diagnostic yield was 43% with VCE and 30% with MRI. The diagnostic yield of VCE was superior to that of MRI in the upper small bowel in both Groups I and II. VCE is superior to MRI for the detection of lesions related to Crohn's disease or obscure gastrointestinal bleeding in the upper small bowel.
-
Nesher, L; Hadi, C M; Salazar, L; Wootton, S H; Garey, K W; Lasco, T; Luce, A M; Hasbun, R
2016-01-01
Meningitis with a negative cerebrospinal fluid Gram stain (CSF-GS) poses a diagnostic challenge as more than 50% of patients remain without an aetiology. The introduction of polymerase chain reaction (PCR) and arboviral serologies have increased diagnostic capabilities, yet large scale epidemiological studies evaluating their use in clinical practice are lacking. We conducted a prospective observational study in New Orleans between November 1999 and September 2008 (early era) when PCR was not widely available, and in Houston between November 2008 and June 2013 (modern era), when PCR was commonly used. Patients presenting with meningitis and negative CSF-GS were followed for 4 weeks. All investigations, PCR used, and results were recorded as they became available. In 323 patients enrolled, PCR provided the highest diagnostic yield (24·2%) but was ordered for 128 (39·6%) patients; followed by serology for arboviruses (15%) that was ordered for 100 (31%) of all patients. The yield of blood cultures was (10·3%) and that of CSF cultures was 4%; the yield for all other tests was <10%. Overall, 65% of the patients remained without a diagnosis at 4 weeks: 72·1% in early era vs. 53·4% (P < 0·01) in modern era; this change was attributed to diagnosing more viral pathogens, 8·3% and 26·3% (P < 0·01), respectively. The introduction of PCR and arboviral serologies has improved the yield of diagnosing patients with meningitis and a negative CSF-GS, but both tests are being under-utilized.
-
Rahman, Merajur; Akerman, Stuart; DeVito, Bethany; Miller, Larry; Akerman, Meredith; Sultan, Keith
2015-05-14
To evaluate the completion rate and diagnostic yield of the PillCam SB2-ex in comparison to the PillCam SB2. Two hundred cases using the 8-h PillCam SB2 were retrospectively compared to 200 cases using the 12 h PillCam SB2-ex at a tertiary academic center. Endoscopically placed capsules were excluded from the study. Demographic information, indications for capsule endoscopy, capsule type, study length, completion of exam, clinically significant findings, timestamp of most distant finding, and significant findings beyond 8 h were recorded. The 8 and 12 h capsule groups were well matched respectively for both age (70.90 ± 14.19 vs 71.93 ± 13.80, P = 0.46) and gender (45.5% vs 48% male, P = 0.69). The most common indications for the procedure in both groups were anemia and obscure gastrointestinal bleeding. PillCam SB2-ex had a significantly higher completion rate than PillCam SB2 (88% vs 79.5%, P = 0.03). Overall, the diagnostic yield was greater for the 8 h capsule (48.5% for SB2 vs 35% for SB2-ex, P = 0.01). In 4/70 (5.7%) of abnormal SB2-ex exams the clinically significant finding was noted in the small bowel beyond the 8 h mark. In our study, we found the PillCam SB2-ex to have a significantly increased completion rate, though without any improvement in diagnostic yield compared to the PillCam SB2.
-
Lawn, Stephen D; Kerkhoff, Andrew D; Burton, Rosie; Schutz, Charlotte; Boulle, Andrew; Vogt, Monica; Gupta-Wright, Ankur; Nicol, Mark P; Meintjes, Graeme
2017-03-21
We previously reported that one-third of HIV-positive adults requiring medical admission to a South African district hospital had laboratory-confirmed tuberculosis (TB) and that almost two-thirds of cases could be rapidly diagnosed using Xpert MTB/RIF-testing of concentrated urine samples obtained on the first day of admission. Implementation of urine-based, routine, point-of-care TB screening is an attractive intervention that might be facilitated by use of a simple, low-cost diagnostic tool, such as the Determine TB-LAM lateral-flow rapid test for HIV-associated TB. Sputum, urine and blood samples were systematically obtained from unselected HIV-positive adults within 24 hours of admission to a South African township hospital. Additional clinical samples were obtained during hospitalization as clinically indicated. TB was defined by the detection of Mycobacterium tuberculosis in any sample using Xpert MTB/RIF or liquid culture. The diagnostic yield, accuracy and prognostic value of urine-lipoarabinomannan (LAM) testing were determined, but urine-LAM results did not inform treatment decisions. Consecutive HIV-positive adult acute medical admissions not already receiving TB treatment (n = 427) were enrolled regardless of clinical presentation or symptoms. TB was diagnosed in 139 patients (TB prevalence 32.6%; median CD4 count 80 cells/μL). In the first 24 hours of admission, sputum (spot and/or induced) samples were obtained from 37.0% of patients and urine samples from 99.5% of patients (P < 0.001). The diagnostic yields from these specimens were 19.4% (n = 27/139) for sputum-microscopy, 26.6% (n = 37/139) for sputum-Xpert, 38.1% (n = 53/139) for urine-LAM and 52.5% (n = 73/139) for sputum-Xpert/urine-LAM combined (P < 0.01). Corresponding yields among patients with CD4 counts <100 cells/μL were 18.9%, 24.3%, 55.4% and 63.5%, respectively (P < 0.01). The diagnostic yield of urine-LAM was unrelated to respiratory symptoms, and LAM assay specificity (using a grade-2 cut-off) was 98.9% (274/277; 95% confidence interval [CI] 96.9-99.8). Among TB cases, positive urine-LAM status was strongly associated with mortality at 90 days (adjusted hazard ratio 4.20; 95% CI 1.50-11.75). Routine testing for TB in newly admitted HIV-positive adults using Determine TB-LAM to test urine provides major incremental diagnostic yield with very high specificity when used in combination with sputum testing and has important utility among those without respiratory TB symptoms and/or unable to produce sputum. The assay also rapidly identifies individuals with a poor prognosis.
-
Schneeberger, Christian
2004-07-01
GENOSENSE Diagnostics GmbH, a company specialized in preventive genetic diagnostics, has committed itself to applying molecular medical knowledge to realizing the vision of individual, preventive and patient-tailored medicine. GENOSENSE offers a unique line of preventive genomic diagnostic profiles. Each profile focuses on a carefully selected set of polymorphisms associated with particular diseases or physiologic imbalances. GENOSENSE does not only provide the genetic test results, but highly capable medical experts 'translate' the results into a clinical language and assist the customer with established support regarding their medical interpretation. In addition, the company provides academic institutions and pharmaceutical companies with turnkey solutions for research-based projects.
-
Fishing diseased abalone to promote yield and conservation
Ben-Horin, Tal; Bidegain, Gorka; Lenihan, Hunter S.
2016-01-01
Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value. PMID:26880843
-
Fishing diseased abalone to promote yield and conservation.
Ben-Horin, Tal; Lafferty, Kevin D; Bidegain, Gorka; Lenihan, Hunter S
2016-03-05
Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value. © 2016 The Author(s).
-
Fishing diseased abalone to promote yield and conservation
Ben-Horin, Tal; Lafferty, Kevin D.; Bidegain, Gorka; Lenihan, Hunter S.
2016-01-01
Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value.
-
Ethical aspects of capsule endoscopy.
Niv, Yaron
2008-01-01
Capsule endoscopy is the most recent innovation in gastrointestinal endoscopy. The capsule contains a video camera that photographs the bowel for 8 h after the capsule has been orally ingested and transmits the images for interpretation to a computerized workstation. Ethical considerations of the use of capsule endoscopy should cover the following main issues: justification of the procedure, its potential benefits and harm, and patient autonomy. Capsule endoscopy has several advantages over traditional endoscopy. The procedure is painless, does not require sedation, is easy to perform and for the first time enables exploration of the entire small bowel at high magnification. However, the clinician cannot control its passive advance along the bowel. In addition, the examination may be incomplete, as the capsule reaches the cecum in only 80% of cases. This paper discusses the problems related to the new endoscopic procedure, the diagnostic yield in comparison with other procedures, proper indications for the procedure, outcome and complications. Copyright 2008 S. Karger AG, Basel.
-
Ruan, Sheng-Yuan; Chuang, Yu-Chung; Wang, Jann-Yuan; Lin, Jou-Wei; Chien, Jung-Yien; Huang, Chun-Ta; Kuo, Yao-Wen; Lee, Li-Na; Yu, Chong-Jen J
2012-09-01
Tuberculous pleurisy is traditionally indicated by extreme lymphocytosis in pleural fluid and low yield of effusion culture. However, there is considerable inconsistency among previous study results. In addition, these data should be updated due to early effusion studies and advances in culture methods. From January 2004 to June 2009, patients with tuberculous pleurisy were retrospectively identified from the mycobacteriology laboratories and the pathology and tuberculosis registration databases of two hospitals in Taiwan where tuberculosis is endemic. Pleural fluid characteristics and yields of mycobacterial cultures using liquid media were evaluated. A total of 382 patients with tuberculous pleurisy were identified. The median lymphocyte percentage of total cells in pleural fluids was 84% (IQR 64-95%) and 17% of cases had a lymphocyte percentage of <50%. The lymphocyte percentage was negatively associated with the probability of a positive effusion culture (OR 0.97; 95% CI 0.96 to 0.99). The diagnostic yields were 63% for effusion culture, 48% for sputum culture, 79% for the combination of effusion and sputum cultures, and 74% for histological examination of pleural biopsy specimens. The degree of lymphocyte predominance in tuberculous pleurisy was lower than was previously thought. The lymphocyte percentage in pleural fluid was negatively associated with the probability of a positive effusion culture. With the implementation of a liquid culture method, the sensitivity of effusion culture was much higher than has been previously reported, and the combination of effusion and sputum cultures provided a good diagnostic yield.
-
Maeda, Kiminori; Storey, Jonathan G; Liddell, Paul A; Gust, Devens; Hore, P J; Wedge, C J; Timmel, Christiane R
2015-02-07
We present a study of a carotenoid-porphyrin-fullerene triad previously shown to function as a chemical compass: the photogenerated carotenoid-fullerene radical pair recombines at a rate sensitive to the orientation of an applied magnetic field. To characterize the system we develop a time-resolved Low-Frequency Reaction Yield Detected Magnetic Resonance (tr-LF-RYDMR) technique; the effect of varying the relative orientation of applied static and 36 MHz oscillating magnetic fields is shown to be strongly dependent on the strength of the oscillating magnetic field. RYDMR is a diagnostic test for involvement of the radical pair mechanism in the magnetic field sensitivity of reaction rates or yields, and has previously been applied in animal behavioural experiments to verify the involvement of radical-pair-based intermediates in the magnetic compass sense of migratory birds. The spectroscopic selection rules governing RYDMR are well understood at microwave frequencies for which the so-called 'high-field approximation' is valid, but at lower frequencies different models are required. For example, the breakdown of the rotating frame approximation has recently been investigated, but less attention has so far been given to orientation effects. Here we gain physical insights into the interplay of the different magnetic interactions affecting low-frequency RYDMR experiments performed in the challenging regime in which static and oscillating applied magnetic fields as well as internal electron-nuclear hyperfine interactions are of comparable magnitude. Our observations aid the interpretation of existing RYDMR-based animal behavioural studies and will inform future applications of the technique to verify and characterize further the biological receptors involved in avian magnetoreception.
-
[Current status and clinical application prospect of Akabane's test].
Wang, Wenjie; Du, Yanjun
2016-06-12
The Akabane's test is one of the meridian diagnostic methods. Compared with the current meridian diagnostic methods, it has the advantages of convenience and efficiency, but it also has several disadvantages such as the accuracy is difficult to control, the outcome interpretation is limited, etc. In this paper, the influence factors of Akabane's test were analyzed one by one, especially proposed personal opinion on outcome interpretation, which could ascertain the location and nature of disease, leading to disease syndrome. With accurate syndrome, the treatment plan could be established. The application prospect of Akabane's test was initially explored, and it was proposed that wearable automation equipment could be one of the development directions.
-
Interpreting the Laboratory Reports for Vit D.
Sarmah, Devajit; Sharma, Booloo
2014-09-01
Importance for Vit D estimation has increased in the recent years due to its link to various diseases. Measurements of Vit D by different diagnostic laboratories is however not uniform. There is variation pertaining to assay methodology and also variation in the measurement of different metabolites of Vit D. There are also various confounders which influence Vit D assays and which in most instances are overlooked. Also a matter of concern regarding Vit D assays is the lack of assay standardisation. These factors contribute to the variation in the reports generated by the diagnostic laboratories. Therefore interpretation of Vit D reports needs proper understanding of these interfering factors and further reports need to be correlated substantially with the clinical findings.
-
Advanced Diagnostics for Reacting Flows
2006-06-01
TECHNICAL DISCUSSION: 1. Infrared-PLIF Imaging Diagnostics using Vibrational Transitions IR-PLIF allows for imaging a group of molecular species important...excitation of IR-active vibrational modes with imaging of the subsequent vibrational fluorescence. Quantitative interpretation requires knowledge of...the vibrational energy transfer processes, and hence in recent years we have been developing models for infrared fluorescence. During the past year
-
Ultrasound of the thyroid and parathyroid glands.
Barraclough, B M; Barraclough, B H
2000-02-01
The superficial position of thyroid and parathyroid glands facilitates the use of diagnostic ultrasound (US) as an imaging technique. Techniques of image acquisition and interpretation are described in detail. Size and morphology of glands can be defined easily. The most important use of US guided biopsy in relation to thyroid and parathyroid glands is to increase diagnostic accuracy.
-
Kapplinger, Jamie D; Pundi, Krishna N; Larson, Nicholas B; Callis, Thomas E; Tester, David J; Bikker, Hennie; Wilde, Arthur A M; Ackerman, Michael J
2018-02-01
Pathogenic RYR2 variants account for ≈60% of clinically definite cases of catecholaminergic polymorphic ventricular tachycardia. However, the rate of rare benign RYR2 variants identified in the general population remains a challenge for genetic test interpretation. Therefore, we examined the results of the RYR2 genetic test among patients referred for commercial genetic testing and examined factors impacting variant interpretability. Frequency and location comparisons were made for RYR2 variants identified among 1355 total patients of varying clinical certainty and 60 706 Exome Aggregation Consortium controls. The impact of the clinical phenotype on the yield of RYR2 variants was examined. Six in silico tools were assessed using patient- and control-derived variants. A total of 18.2% (218/1200) of patients referred for commercial testing hosted rare RYR2 variants, statistically less than the 59% (46/78) yield among clinically definite cases, resulting in a much higher potential genetic false discovery rate among referrals considering the 3.2% background rate of rare, benign RYR2 variants. Exclusion of clearly putative pathogenic variants further complicates the interpretation of the next novel RYR2 variant. Exonic/topologic analyses revealed overrepresentation of patient variants in exons covering only one third of the protein. In silico tools largely failed to show evidence toward enhancement of variant interpretation. Current expert recommendations have resulted in increased use of RYR2 genetic testing in patients with questionable clinical phenotypes. Using the largest to date catecholaminergic polymorphic ventricular tachycardia patient versus control comparison, this study highlights important variables in the interpretation of variants to overcome the 3.2% background rate that confounds RYR2 variant interpretation. © 2018 American Heart Association, Inc.
-
VLSI (Very Large Scale Integrated Circuits) Design with the MacPitts Silicon Compiler.
1985-09-01
the background. If the algorithm is not fully debugged, then issue instead macpitts basename herald so MacPitts diagnostics and Liszt diagnostics both...command interpreter. Upon compilation, however, the following LI!F compiler ( Liszt ) diagnostic results, Error: Non-number to minus nil where the first...language used in the MacPitts source code. The more instructive solution is to write the Franz LISP code to decide if a jumper wire is needed, and if so, to
-
[Diagnostic imaging and acute abdominal pain].
Liljekvist, Mads Svane; Pommergaard, Hans-Christian; Burcharth, Jakob; Rosenberg, Jacob
2015-01-19
Acute abdominal pain is a common clinical condition. Clinical signs and symptoms can be difficult to interpret, and diagnostic imaging may help to identify intra-abdominal disease. Conventional X-ray, ultrasound (US) and computed tomography (CT) of the abdomen vary in usability between common surgical causes of acute abdominal pain. Overall, conventional X-ray cannot confidently diagnose or rule out disease. US and CT are equally trustworthy for most diseases. US with subsequent CT may enhance diagnostic precision. Magnetic resonance seems promising for future use in acute abdominal imaging.
-
Physical processes and diagnostics of gamma-ray burst emission
NASA Technical Reports Server (NTRS)
Harding, Alice K.
1992-01-01
With improved data from BATSE and other instruments, it is important to develop a range of diagnostic tools to link gamma-ray burst observations with theory. I will review some of the physical processes which may take place to form the spectrum of gamma-ray burst sources, assuming that the bursts originate on strongly magnetized neutron stars. The important diagnostics that these processes provide to probe the emission region and how they might be used to interpret observed spectra will also be discussed.
-
Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments
NASA Astrophysics Data System (ADS)
Hatarik, R.; Sayre, D. B.; Caggiano, J. A.; Phillips, T.; Eckart, M. J.; Bond, E. J.; Cerjan, C.; Grim, G. P.; Hartouni, E. P.; Knauer, J. P.; Mcnaney, J. M.; Munro, D. H.
2015-11-01
Neutron time-of-flight diagnostics have long been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d + t → n + α (DT) and d + d → n + 3He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (Tion) and cold fuel areal density. We report on novel methodologies used to determine neutron yield, apparent Tion, and DSR. These methods invoke a single temperature, static fluid model to describe the neutron peaks from DD and DT reactions and a spline description of the DT spectrum to determine the DSR. Both measurements are performed using a forward modeling technique that includes corrections for line-of-sight attenuation and impulse response of the detection system. These methods produce typical uncertainties for DT Tion of 250 eV, 7% for DSR, and 9% for the DT neutron yield. For the DD values, the uncertainties are 290 eV for Tion and 10% for the neutron yield.
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hartlein, Rick; Hampton, Nigel; Perkel, Josh
2016-02-01
The Cable Diagnostic Focused Initiative (CDFI) played a significant and powerful role in clarifying the concerns and understanding the benefits of performing diagnostic tests on underground power cable systems. This project focused on the medium and high voltage cable systems used in utility transmission and distribution (T&D) systems. While many of the analysis techniques and interpretations are applicable to diagnostics and cable systems outside of T&D, areas such as generating stations (nuclear, coal, wind, etc.) and other industrial environments were not the focus. Many large utilities in North America now deploy diagnostics or have changed their diagnostic testing approach asmore » a result of this project. Previous to the CDFI, different diagnostic technology providers individually promoted their approach as the “the best” or “the only” means of detecting cable system defects.« less
-
Tsalik, Ephraim L.; Petzold, Elizabeth; Kreiswirth, Barry N.; Bonomo, Robert A.; Banerjee, Ritu; Lautenbach, Ebbing; Evans, Scott R.; Hanson, Kimberly E.; Klausner, Jeffrey D.
2017-01-01
Abstract Diagnostics are a cornerstone of the practice of infectious diseases. However, various limitations frequently lead to unmet clinical needs. In most other domains, diagnostics focus on narrowly defined questions, provide readily interpretable answers, and use true gold standards for development. In contrast, infectious diseases diagnostics must contend with scores of potential pathogens, dozens of clinical syndromes, emerging pathogens, rapid evolution of existing pathogens and their associated resistance mechanisms, and the absence of gold standards in many situations. In spite of these challenges, the importance and value of diagnostics cannot be underestimated. Therefore, the Antibacterial Resistance Leadership Group has identified diagnostics as 1 of 4 major areas of emphasis. Herein, we provide an overview of that development, highlighting several examples where innovation in study design, content, and execution is advancing the field of infectious diseases diagnostics. PMID:28350903
-
The Effect of Client Ethnicity on Clinical Interpretation of the MMPI-2
ERIC Educational Resources Information Center
Knaster, Cara A.; Micucci, Joseph A.
2013-01-01
Client ethnicity has been shown to affect clinicians' diagnostic impressions. However, it is not known whether interpretation of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) clinical scales is affected by ethnic bias. In this study, clinicians (82 males, 60 females) provided severity ratings for six symptoms based on three MMPI-2…
-
Clinical Laboratories – Production Factories or Specialized Diagnostic Centers
Tóth, Judit
2016-01-01
Since a large proportion of medical decisions are based on laboratory results, clinical laboratories should meet the increasing demand of clinicians and their patients. Huge central laboratories may process over 10 million tests annually; they act as production factories, measuring emergency and routine tests with sufficient speed and accuracy. At the same time, they also serve as specialized diagnostic centers where well-trained experts analyze and interpret special test results. It is essential to improve and constantly monitor this complex laboratory service, by several methods. Sample transport by pneumatic tube system, use of an advanced laboratory information system and point-of-care testing may result in decreased total turnaround time. The optimization of test ordering may result in a faster and more cost-effective laboratory service. Autovalidation can save time for laboratory specialists, when the analysis of more complex results requires their attention. Small teams of experts responsible for special diagnostic work, and their interpretative reporting according to predetermined principles, may help to minimize subjectivity of these special reports. Although laboratory investigations have become so diversely developed in the past decades, it is essential that the laboratory can provide accurate results relatively quickly, and that laboratory specialists can support the diagnosis and monitoring of patients by adequate interpretation of esoteric laboratory methods. PMID:27683528
-
The sense of the body in the dream: Diagnostic capacity in the meanings of dreams.
Giordo, Gianfranco
2016-04-01
The author investigates the oneiric representation of somatic states and the diagnostic capacity of dreams. He draws on Freud's hypotheses on the procedures by which somatic stimuli insert themselves in oneiric elaboration and restructures them according to the recent neurobiological discoveries and to analytical experiences. In the representations of certain dreams, with a psychic interpretation agreed upon by the patients, somatic alterations unknown to the analytical couple were discriminated and confirmed by radiological investigations. These representations were linked to the manifestation of one aspect of the bodily Self, neglected in the precocious maternal relation, that entered the organization of the Self consolidated in the relation with the paternal figure. This conjunction gave origin to the double meaning (somatic and psychic) of the dream. The entering of the somatic representation in the oneiric one did not appear to be the figurative effect, but of a condensation of diagnostic capacity into the meaning of the dream. This characteristic manifested itself in the particular styles of the dreamers, interpretable by an analyst countertransferentially oriented. The perception or scotomization of the condensation in the interpretation of the dream and of the moment had an effect on the evolution of the analysis. Copyright © 2015 Institute of Psychoanalysis.
-
Zvyagin, V N; Rakitin, V A; Fomina, E E
The objective of the present study was the development of the point-digital model for the scaless interpretation of the dermatoglyphic papillary patterns on human fingers that would allow to comprehensively describe, in digital terms, the main characteristics of the traits and perform the quantitative assessment of the frequency of their inheritance. A specially developed computer program, D.glyphic. 7-14 was used to mark the dermatoglyphic patterns on the fingerprints obtained from 30 familial triplets (father + mother + child).The values of all the studied traits for kinship diagnostics were found by calculating the ratios of the sums of differences between the traits in the parent-parent pairs to those in the respective parent-child pairs. The algorithms for the point marking of the traits and reading out the digital information about them have been developed. The traditional dermatoglyphic patterns were selected and the novel ones applied for the use in the framework of the point-digital model for the interpretation of the for diagnostics of consanguineous relationship. The present experimental study has demonstrated the high level of inheritance of the selected traits and the possibility to develop the algorithms and computation techniques for the calculation of consanguineous relationship coefficients based on these traits.
-
Is there Progress? An Overview of Selecting Biomarker Candidates for Major Depressive Disorder
Young, Juan Joseph; Silber, Tim; Bruno, Davide; Galatzer-Levy, Isaac Robert; Pomara, Nunzio; Marmar, Charles Raymond
2016-01-01
Major depressive disorder (MDD) contributes to a significant worldwide disease burden, expected to be second only to heart disease by 2050. However, accurate diagnosis has been a historical weakness in clinical psychiatry. As a result, there is a demand for diagnostic modalities with greater objectivity that could improve on current psychiatric practice that relies mainly on self-reporting of symptoms and clinical interviews. Over the past two decades, literature on a growing number of putative biomarkers for MDD increasingly suggests that MDD patients have significantly different biological profiles compared to healthy controls. However, difficulty in elucidating their exact relationships within depression pathology renders individual markers inconsistent diagnostic tools. Consequently, further biomarker research could potentially improve our understanding of MDD pathophysiology as well as aid in interpreting response to treatment, narrow differential diagnoses, and help refine current MDD criteria. Representative of this, multiplex assays using multiple sources of biomarkers are reported to be more accurate options in comparison to individual markers that exhibit lower specificity and sensitivity, and are more prone to confounding factors. In the future, more sophisticated multiplex assays may hold promise for use in screening and diagnosing depression and determining clinical severity as an advance over relying solely on current subjective diagnostic criteria. A pervasive limitation in existing research is heterogeneity inherent in MDD studies, which impacts the validity of biomarker data. Additionally, small sample sizes of most studies limit statistical power. Yet, as the RDoC project evolves to decrease these limitations, and stronger studies with more generalizable data are developed, significant advances in the next decade are expected to yield important information in the development of MDD biomarkers for use in clinical settings. PMID:27199779
-
Georghiou, Sophia B.; Catanzaro, Donald; Rodrigues, Camilla; Crudu, Valeriu; Victor, Thomas C.; Garfein, Richard S.; Catanzaro, Antonino; Rodwell, Timothy C.
2016-01-01
Accurate identification of drug-resistant Mycobacterium tuberculosis is imperative for effective treatment and subsequent reduction in disease transmission. Line probe assays rapidly detect mutations associated with resistance and wild-type sequences associated with susceptibility. Examination of molecular-level performance is necessary for improved assay result interpretation and for continued diagnostic development. Using data collected from a large, multisite diagnostic study, probe hybridization results from line probe assays, MTBDRplus and MTBDRsl, were compared to those of sequencing, and the diagnostic performance of each individual mutation and wild-type probe was assessed. Line probe assay results classified as resistant due to the absence of wild-type probe hybridization were compared to those of sequencing to determine if novel mutations were inhibiting wild-type probe hybridization. The contribution of absent wild-type probe hybridization to the detection of drug resistance was assessed via comparison to a phenotypic reference standard. In our study, mutation probes demonstrated significantly higher specificities than wild-type probes and wild-type probes demonstrated marginally higher sensitivities than mutation probes, an ideal combination for detecting the presence of resistance conferring mutations while yielding the fewest number of false-positive results. The absence of wild-type probe hybridization without mutation probe hybridization was determined to be primarily the result of failure of mutation probe hybridization and not the result of novel or rare mutations. Compared to phenotypic culture-based drug susceptibility testing, the absence of wild-type probe hybridization without mutation probe hybridization significantly contributed to the detection of phenotypic rifampin and fluoroquinolone resistance with negligible increases in false-positive results. PMID:26763971
-
Challenges in pediatric chronic inflammatory demyelinating polyneuropathy.
Haliloğlu, Göknur; Yüksel, Deniz; Temoçin, Cağri Mesut; Topaloğlu, Haluk
2016-12-01
Chronic inflammatory demyelinating neuropathy, a treatable immune-mediated disease of the peripheral nervous system is less common in childhood compared to adults. Despite different sets of diagnostic criteria, lack of a reliable biologic marker leads to challenges in diagnosis, follow-up and treatment. Our first aim was to review clinical presentation, course, response to treatment, and prognosis in our childhood patients. We also aimed to document diagnostic and therapeutic pitfalls and challenges at the bedside. Our original cohort consisted of 23 pediatric patients who were referred to us with a clinical diagnosis of chronic inflammatory demyelinating neuropathy. Seven patients reaching to an alternative diagnosis were excluded. In the remaining patients, diagnostic, treatment and follow-up data were compared in typical patients who satisfied both clinical and electrodiagnostic criteria and atypical patients who failed to meet minimal research chronic inflammatory demyelinating neuropathy electrodiagnostic requirements. Eight of 16 patients (50%) met the minimal chronic inflammatory demyelinating neuropathy research diagnostic requirements. There was only a statistically significant difference (p = 0.010) in terms of European Neuromuscular Centre childhood chronic inflammatory diagnostic mandatory clinical criteria between the two groups. Misdiagnosis due to errors in electrophysiological interpretation (100%, n = 8), cerebrospinal fluid cytoalbuminologic dissociation (100%, n = 4 and/or subjective improvement on any immunotherapy modality (80 ± 19.27%)) was frequent. Pediatric CIDP is challenging in terms of diagnostic and therapeutic pitfalls at the bedside. Diagnostic errors due to electrophysiological interpretation, cerebrospinal fluid cytoalbuminologic dissociation, and/or subjective improvement on immunotherapy should be considered. Copyright © 2016 Elsevier B.V. All rights reserved.
-
Qumseya, Bashar J; Wang, Haibo; Badie, Nicole; Uzomba, Rosemary N; Parasa, Sravanthi; White, Donna L; Wolfsen, Herbert; Sharma, Prateek; Wallace, Michael B
2013-12-01
US guidelines recommend surveillance of patients with Barrett's esophagus (BE) to detect dysplasia. BE conventionally is monitored via white-light endoscopy (WLE) and a collection of random biopsy specimens. However, this approach does not definitively or consistently detect areas of dysplasia. Advanced imaging technologies can increase the detection of dysplasia and cancer. We investigated whether these imaging technologies can increase the diagnostic yield for the detection of neoplasia in patients with BE, compared with WLE and analysis of random biopsy specimens. We performed a systematic review, using Medline and Embase, to identify relevant peer-review studies. Fourteen studies were included in the final analysis, with a total of 843 patients. Our metameter (estimate) of interest was the paired-risk difference (RD), defined as the difference in yield of the detection of dysplasia or cancer using advanced imaging vs WLE. The estimated paired-RD and 95% confidence interval (CI) were obtained using random-effects models. Heterogeneity was assessed by means of the Q statistic and the I(2) statistic. An exploratory meta-regression was performed to look for associations between the metameter and potential confounders or modifiers. Overall, advanced imaging techniques increased the diagnostic yield for detection of dysplasia or cancer by 34% (95% CI, 20%-56%; P < .0001). A subgroup analysis showed that virtual chromoendoscopy significantly increased the diagnostic yield (RD, 0.34; 95% CI, 0.14-0.56; P < .0001). The RD for chromoendoscopy was 0.35 (95% CI, 0.13-0.56; P = .0001). There was no significant difference between virtual chromoendoscopy and chromoendoscopy, based on Student t test analysis (P = .45). Based on a meta-analysis, advanced imaging techniques such as chromoendoscopy or virtual chromoendoscopy significantly increase the diagnostic yield for identification of dysplasia or cancer in patients with BE. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.
-
NASA Astrophysics Data System (ADS)
Krupinski, Elizabeth A.; Berbaum, Kevin S.; Caldwell, Robert; Schartz, Kevin M.
2012-02-01
Radiologists are reading more cases with more images, especially in CT and MRI and thus working longer hours than ever before. There have been concerns raised regarding fatigue and whether it impacts diagnostic accuracy. This study measured the impact of reader visual fatigue by assessing symptoms, visual strain via dark focus of accommodation, and diagnostic accuracy. Twenty radiologists and 20 radiology residents were given two diagnostic performance tests searching CT chest sequences for a solitary pulmonary nodule before (rested) and after (tired) a day of clinical reading. 10 cases used free search and navigation, and the other 100 cases used preset scrolling speed and duration. Subjects filled out the Swedish Occupational Fatigue Inventory (SOFI) and the oculomotor strain subscale of the Simulator Sickness Questionnaire (SSQ) before each session. Accuracy was measured using ROC techniques. Using Swensson's technique yields an ROC area = 0.86 rested vs. 0.83 tired, p (one-tailed) = 0.09. Using Swensson's LROC technique yields an area = 0.73 rested vs. 0.66 tired, p (one-tailed) = 0.09. Using Swensson's Loc Accuracy technique yields an area = 0.77 rested vs. 0.72 tired, p (one-tailed) = 0.13). Subjective measures of fatigue increased significantly from early to late reading. To date, the results support our findings with static images and detection of bone fractures. Radiologists at the end of a long work day experience greater levels of measurable visual fatigue or strain, contributing to a decrease in diagnostic accuracy. The decrease in accuracy was not as great however as with static images.
-
Diagnostic yield of 24-hour esophageal manometry in non-cardiac chest pain.
Barret, M; Herregods, T V K; Oors, J M; Smout, A J P M; Bredenoord, A J
2016-08-01
In the past, ambulatory 24-h manometry has been shown useful for the evaluation of patients with non-cardiac chest pain (NCCP). With the diagnostic improvements brought by pH-impedance monitoring and high-resolution manometry (HRM), the contribution of ambulatory 24-h manometry to the diagnosis of esophageal hypertensive disorders has become uncertain. Our aim was to assess the additional diagnostic yield of ambulatory manometry to HRM and ambulatory pH-impedance monitoring in this patient population. All patients underwent 24-h ambulatory pressure-pH-impedance monitoring and HRM. Patients had retrosternal pain as a predominant symptom and no explanation after cardiologic and digestive endoscopic evaluations. Diagnostic measurements were analyzed by two independent physicians. Fifty-nine patients met the inclusion criteria; 37.3% of the patients had their symptoms explained by abnormalities on pH-impedance monitoring and 6.8% by ambulatory manometry. Functional chest pain was diagnosed in 52.5% of the patients. High-resolution manometry, using the Chicago Classification v3.0 criteria alone, did not identify any of the four patients with esophageal spasm on ambulatory manometry. However, taking into account other abnormalities, such as simultaneous (rapid) or repetitive contractions, HRM had a sensitivity of 75% and a specificity of 98.2% for the diagnosis of esophageal spasm. In the work-up of NCCP, ambulatory 24-h manometry has a low additional diagnostic yield. However, it remains the best technique to identify esophageal spasm as the cause of symptoms. This is particularly useful when an unequivocal diagnosis is needed before treatment. © 2016 John Wiley & Sons Ltd.
-
Wright, Caroline F; McRae, Jeremy F; Clayton, Stephen; Gallone, Giuseppe; Aitken, Stuart; FitzGerald, Tomas W; Jones, Philip; Prigmore, Elena; Rajan, Diana; Lord, Jenny; Sifrim, Alejandro; Kelsell, Rosemary; Parker, Michael J; Barrett, Jeffrey C; Hurles, Matthew E; FitzPatrick, David R; Firth, Helen V
2018-01-11
PurposeGiven the rapid pace of discovery in rare disease genomics, it is likely that improvements in diagnostic yield can be made by systematically reanalyzing previously generated genomic sequence data in light of new knowledge.MethodsWe tested this hypothesis in the United Kingdom-wide Deciphering Developmental Disorders study, where in 2014 we reported a diagnostic yield of 27% through whole-exome sequencing of 1,133 children with severe developmental disorders and their parents. We reanalyzed existing data using improved variant calling methodologies, novel variant detection algorithms, updated variant annotation, evidence-based filtering strategies, and newly discovered disease-associated genes.ResultsWe are now able to diagnose an additional 182 individuals, taking our overall diagnostic yield to 454/1,133 (40%), and another 43 (4%) have a finding of uncertain clinical significance. The majority of these new diagnoses are due to novel developmental disorder-associated genes discovered since our original publication.ConclusionThis study highlights the importance of coupling large-scale research with clinical practice, and of discussing the possibility of iterative reanalysis and recontact with patients and health professionals at an early stage. We estimate that implementing parent-offspring whole-exome sequencing as a first-line diagnostic test for developmental disorders would diagnose >50% of patients.GENETICS in MEDICINE advance online publication, 11 January 2018; doi:10.1038/gim.2017.246.
-
2001-10-25
wavelet decomposition of signals and classification using neural network. Inputs to the system are the heart sound signals acquired by a stethoscope in a...Proceedings. pp. 415–418, 1990. [3] G. Ergun, “An intelligent diagnostic system for interpretation of arterpartum fetal heart rate tracings based on ANNs and...AN INTELLIGENT PATTERN RECOGNITION SYSTEM BASED ON NEURAL NETWORK AND WAVELET DECOMPOSITION FOR INTERPRETATION OF HEART SOUNDS I. TURKOGLU1, A
-
Circulating Tumor Cells: What Is in It for the Patient? A Vision towards the Future
van de Stolpe, Anja; den Toonder, Jaap M. J.
2014-01-01
Knowledge on cellular signal transduction pathways as drivers of cancer growth and metastasis has fuelled development of “targeted therapy” which “targets” aberrant oncogenic signal transduction pathways. These drugs require nearly invariably companion diagnostic tests to identify the tumor-driving pathway and the cause of the abnormal pathway activity in a tumor sample, both for therapy response prediction as well as for monitoring of therapy response and emerging secondary drug resistance. Obtaining sufficient tumor material for this analysis in the metastatic setting is a challenge, and circulating tumor cells (CTCs) may provide an attractive alternative to biopsy on the premise that they can be captured from blood and the companion diagnostic test results are correctly interpreted. We discuss novel companion diagnostic directions, including the challenges, to identify the tumor driving pathway in CTCs, which in combination with a digital pathology platform and algorithms to quantitatively interpret complex CTC diagnostic results may enable optimized therapy response prediction and monitoring. In contrast to CTC-based companion diagnostics, CTC enumeration is envisioned to be largely replaced by cell free tumor DNA measurements in blood for therapy response and recurrence monitoring. The recent emergence of novel in vitro human model systems in the form of cancer-on-a-chip may enable elucidation of some of the so far elusive characteristics of CTCs, and is expected to contribute to more efficient CTC capture and CTC-based diagnostics. PMID:24879438
-
ERIC Educational Resources Information Center
Welch, Lisa C.; Lutfey, Karen E.; Gerstenberger, Eric; Grace, Matthew
2012-01-01
Nonmedical factors and diagnostic certainty contribute to variation in clinical decision making, but the process by which this occurs remains unclear. We examine how physicians' interpretations of patient sex-gender affect diagnostic certainty and, in turn, decision making for coronary heart disease. Data are from a factorial experiment of 256…
-
Jeong, Seok Hoo; Yoon, Hyun Hwa; Kim, Eui Joo; Kim, Yoon Jae; Kim, Yeon Suk; Cho, Jae Hee
2017-01-01
Abstract Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the accurate diagnostic method for pancreatic masses and its accuracy is affected by various FNA methods and EUS equipment. Therefore, we aimed to elucidate the instrumental and methodologic factors for determining the diagnostic yield of EUS-FNA for pancreatic solid masses without an on-site cytopathology evaluation. We retrospectively reviewed the medical records of 260 patients (265 pancreatic solid masses) who underwent EUS-FNA. We compared historical conventional EUS groups with high-resolution imaging devices and finally analyzed various factors affecting EUS-FNA accuracy. In total, 265 pancreatic solid masses of 260 patients were included in this study. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNA for pancreatic solid masses without on-site cytopathology evaluation were 83.4%, 81.8%, 100.0%, 100.0%, and 34.3%, respectively. In comparison with conventional image group, high-resolution image group showed the increased accuracy, sensitivity and specificity of EUS-FNA (71.3% vs 92.7%, 68.9% vs 91.9%, and 100% vs 100%, respectively). On the multivariate analysis with various instrumental and methodologic factors, high-resolution imaging (P = 0.040, odds ratio = 3.28) and 3 or more needle passes (P = 0.039, odds ratio = 2.41) were important factors affecting diagnostic yield of pancreatic solid masses. High-resolution imaging and 3 or more passes were the most significant factors influencing diagnostic yield of EUS-FNA in patients with pancreatic solid masses without an on-site cytopathologist. PMID:28079803
-
Fernández-Ibieta, M; Rojas Ticona, J; Villamil, V; Guirao Piñera, M J; López García, A; Zambudio Carmona, G
2017-11-01
In the historical series, the diagnostic yield of lumbosacral magnetic resonance imaging to rule out occult spinal dysraphism (or occult myelodysplasia), requested by paediatric urology, ranged from 2% to 15%. The aim of this study was to define our cost-effectiveness in children with urinary symptoms and to define endpoints that increase the possibility of finding occult spinal dysraphism. A screening was conducted on patients with urinary dysfunction for whom an magnetic resonance imaging was requested by the paediatric urology clinic, for persistent symptoms after treatment, voiding dysfunction or other clinical or urodynamic findings. We analysed clinical (UTI, daytime leaks, enuresis, voiding dysfunction, urgency, renal ultrasonography, lumbosacral radiography, history of acute urine retention, skin stigma and myalgia) and urodynamic endpoints (hyperactivity or areflexia, voiding dysfunction, interrupted pattern, accommodation value and maximum flow). A univariate analysis was conducted with SPSS 20.0. We analysed 21 patients during the period 2011-2015. The median age was 6 years (3-10). Three patients (14.3%) had occult spinal dysraphism: one spinal lipoma, one filum lipomatosus and one caudal regression syndrome with channel stenosis. The endpoints with statistically significant differences were the myalgias and the history of acute urine retention (66.7% vs. 5.6%, P=.04; OR= 34; 95%CI: 1.5-781 for both endpoints). The diagnostic yield of magnetic resonance imaging requested for children with urinary dysfunctions without skin stigma or neuro-orthopaedic abnormalities is low, although nonnegligible. In this group, the patients with a history of acute urine retention and muscle pain (pain, «cramps») can experience a greater diagnostic yield or positive predictive value. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.
-
Cohen, Micah G; McMahon, Colm J; Kung, Justin W; Wu, Jim S
2016-05-01
The purpose of this study was to compare manual and battery-powered bone biopsy systems for diagnostic yield and procedural factors during core needle biopsy of sclerotic bone lesions. A total of 155 consecutive CT-guided core needle biopsies of sclerotic bone lesions were performed at one institution from January 2006 to November 2014. Before March 2012, lesions were biopsied with manual bone drill systems. After March 2012, most biopsies were performed with a battery-powered system and either noncoaxial or coaxial biopsy needles. Diagnostic yield, crush artifact, CT procedure time, procedure radiation dose, conscious sedation dose, and complications were compared between the manual and battery-powered core needle biopsy systems by Fisher exact test and t test. One-way ANOVA was used for subgroup analysis of the two battery-powered systems for procedure time and radiation dose. The diagnostic yield for all sclerotic lesions was 60.0% (93/155) and was significantly higher with the battery-powered system (73.0% [27/37]) than with the manual systems (55.9% [66/118]) (p = 0.047). There was no significant difference between the two systems in terms of crush artifact, procedure time, radiation dose, conscious sedation administered, or complications. In subgroup analysis, the coaxial battery-powered biopsies had shorter procedure times (p = 0.01) and lower radiation doses (p = 0.002) than the coaxial manual systems, but the noncoaxial battery-powered biopsies had longer average procedure times and higher radiation doses than the coaxial manual systems. In biopsy of sclerotic bone lesions, use of a battery-powered bone drill system improves diagnostic yield over use of a manual system.
-
Interpretation of quantum yields exceeding unity in photoelectrochemical systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Szklarczyk, M.; Allen, R.E.
1986-10-20
In photoelectrochemical systems involving light shining on a semiconductor interfaced with an electrolyte, the quantum yield as a function of photon frequency ..nu.. is observed to exhibit a peak at h..nu..roughly-equal2E/sub g/, where E/sub g/ is the band gap of the semiconductor. The maximum in this peak is sometimes found to exceed unity. We provide an interpretation involving surface states and inelastic electron-electron scattering. The theory indicates that the effect should be observable for p-type semiconductors, but not n-type.
-
Interpretation of fast-ion signals during beam modulation experiments
Heidbrink, W. W.; Collins, C. S.; Stagner, L.; ...
2016-07-22
Fast-ion signals produced by a modulated neutral beam are used to infer fast-ion transport. The measured quantity is the divergence of perturbed fast-ion flux from the phase-space volume measured by the diagnostic, ∇•more » $$\\bar{Γ}$$. Since velocity-space transport often contributes to this divergence, the phase-space sensitivity of the diagnostic (or “weight function”) plays a crucial role in the interpretation of the signal. The source and sink make major contributions to the signal but their effects are accurately modeled by calculations that employ an exponential decay term for the sink. Recommendations for optimal design of a fast-ion transport experiment are given, illustrated by results from DIII-D measurements of fast-ion transport by Alfv´en eigenmodes. Finally, the signal-to-noise ratio of the diagnostic, systematic uncertainties in the modeling of the source and sink, and the non-linearity of the perturbation all contribute to the error in ∇•$$\\bar{Γ}$$.« less
-
Cone beam tomographic imaging anatomy of the maxillofacial region.
Angelopoulos, Christos
2008-10-01
Multiplanar imaging is a fairly new concept in diagnostic imaging available with a number of contemporary imaging modalities such as CT, MR imaging, diagnostic ultrasound, and others. This modality allows reconstruction of images in different planes (flat or curved) from a volume of data that was acquired previously. This concept makes the diagnostic process more interactive, and proper use may increase diagnostic potential. At the same time, the complexity of the anatomical structures on the maxillofacial region may make it harder for these images to be interpreted. This article reviews the anatomy of maxillofacial structures in planar imaging, and more specifically cone-beam CT images.
-
Diagnostic Yield and Safety of Brain Biopsy for Suspected Primary Central Nervous System Angiitis.
Torres, Jose; Loomis, Caitlin; Cucchiara, Brett; Smith, Michelle; Messé, Steven
2016-08-01
The utility and safety of brain biopsy for suspected primary angiitis of the central nervous system (PACNS) are uncertain. Factors predictive of a positive biopsy have not been well described. Our aim was to evaluate the diagnostic yield and safety of brain biopsy in suspected PACNS and determine whether any prebiopsy variables are associated with a positive biopsy. This is a retrospective study of consecutive patients who underwent diagnostic brain biopsy for PACNS at a single institution. The relationship between biopsy yield and patient demographics, surgical technique, laboratory testing, neuroimaging, biopsy characteristics, and prebiopsy immunosuppressive therapy were examined. PACNS was confirmed in 9 of 79 patients (11%). Biopsy identified alternative diagnoses in 24 patients (30%), with cerebral amyloid angiopathy (8 patients), encephalitis (5 patients), demyelination (3 patients), and CNS lymphoma (3 patients) most commonly found. There was no correlation between a positive biopsy and cerebrospinal fluid results, neuroimaging, surgical technique, biopsy characteristics, or preoperative immunosuppressive therapy. Smaller biopsies (P=0.02) and closed procedures (P=0.013) were less likely to yield a diagnosis. Postoperative complications occurred in 13 patients (16%), 3 (4%) of which were serious. Brain biopsy leads to pathological confirmation of vasculitis in a minority of suspected PACNS cases but alternative diagnoses are often identified. Importantly, rare but meaningful complications may occur. © 2016 American Heart Association, Inc.
-
Historical analysis of experience with small bowel capsule endoscopy in a spanish tertiary hospital.
Egea Valenzuela, Juan; Carrilero Zaragoza, Gabriel; Iglesias Jorquera, Elena; Tomás Pujante, Paula; Alberca de Las Parras, Fernando; Carballo Álvarez, Fernando
2017-02-01
Capsule endoscopy was approved by the FDA in 2001. Gastrointestinal bleeding and inflammatory bowel disease are the main indications. It has been available in our hospital since 2004. We retrospectively analysed data from patients who underwent small bowel capsule endoscopy in our hospital from October 2004 to April 2015. Indications were divided into: Obscure gastrointestinal bleeding (occult and overt), inflammatory bowel disease, and other indications. Findings were divided into: Vascular lesions, inflammatory lesions, other lesions, normal studies, and inconclusive studies. A total of 1027 out of 1291 small bowel studies were included. Mean patient age was 56.45 years; 471 were men and 556 women. The most common lesion observed was angiectasia, as an isolated finding or associated with other lesions. Findings were significant in up to 80% of studies when the indication was gastrointestinal bleeding, but in only 50% of studies in inflammatory bowel disease. Diagnostic yield was low in the group «other indications». No major complications were reported. Small bowel capsule endoscopy has high diagnostic yield in patients with gastrointestinal bleeding, but yield is lower in patients with inflammatory bowel disease. Our experience shows that capsule endoscopy is a safe and useful tool for the diagnosis of small bowel disease. The diagnostic yield of the technique in inflammatory bowel disease must be improved. Copyright © 2016 Elsevier España, S.L.U., AEEH y AEG. All rights reserved.
-
Bain, P; Wareing, A; Henderson, I
2017-09-01
Peer-assisted learning provides a means through which individuals can learn from one another through a reciprocal process. Radiographic image interpretation skills are fundamental to both diagnostic radiography students and medical students due to their shared role in preliminary evaluation of conventional radiographic images. Medical students on graduation, may not be well prepared to carry out image interpretation, since evidence suggests that they perform less well than radiographers in e.g. Accident and Emergency situations. A review of literature was conducted exploring the application of peer-assisted learning within diagnostic radiography and health education more widely as well as the practice of initial image interpretation. An extensive and systematic search strategy was developed which provided a range of material related to the areas. An overview was obtained of the effectiveness of peer-assisted learning and the issues associated with development of image interpretation skills and a degree of discrepancy was identified between the two cohorts regarding their interpretative competence and confidence. This inconsistency may create an opportunity to apply peer-assisted learning, better preparing both disciplines for the practical application of image interpretation skills. The review identified the lack of a substantial evidence base relating to peer-assisted learning in radiography. Peer-assisted learning is not widely embraced in an interprofessional context. Multiple positive factors of such an intervention are identified which outweigh perceived negative issues. Student teacher and learner may benefit as should the clinical service from enhanced practitioner performance. The findings justify further research to develop the evidence base. Copyright © 2017 The College of Radiographers. Published by Elsevier Ltd. All rights reserved.
-
CLINICAL APPROACH TO THE DIAGNOSTIC EVALUATION OF HERDITARY AND ACQUIRED NEUROMUSCULAR DISEASES
McDonald, Craig M.
2012-01-01
SYNOPSIS In the context of a neuromuscular disease diagnostic evaluation, the clinician still must be able to obtain a relevant patient and family history and perform focused general, musculoskeletal, neurologic and functional physical examinations to direct further diagnostic evaluations. Laboratory studies for hereditary neuromuscular diseases include relevant molecular genetic studies. The EMG and nerve conduction studies remain an extension of the physical examination and help to guide further diagnostic studies such as molecular genetic studies, and muscle and nerve biopsies. All diagnostic information needs to be interpreted not in isolation, but within the context of relevant historical information, family history, physical examination findings, and laboratory data, electrophysiologic findings, pathologic findings, and molecular genetic findings if obtained. PMID:22938875
-
[Consanguinity between meridian theory and Bianque's pulse theory].
Huang, Longxiang
2015-05-01
The integral meridian theory is composed of five parts, including meridian course, syndrome, diagnostic method, treating principle and treatment, and the core of it is meridian syndrome. It has been proved by multiple evidences that the meridian syndrome induced by the pathological change in meridian and the death syndrome of pulse penetrating or attaching to the syndrome are all originated from Bianque' s facial color and pulse diagnosis. And regarding the pulse syndrome,there are many different interpretations based on the theory of yin-yang in four seasons before the Han Dynasty. The emerging of Biaoben diagnostic method in Bianque's pulse method and its extensive clinical application promote a new theoretic interpretation the connection of meridians interpreting pulse syndrome directly. Besides, along with the new development of blood-pulse theory of Bianque's medicine, the revolution on meridian theory is aroused as well its theoretical paradigm turning from "tree" type to "ring" type. In other words, Bianque's medicine not only gives birth to meridian theory, but also decides its final development.
-
Language and Speech in Autism.
Gernsbacher, Morton Ann; Morson, Emily M; Grace, Elizabeth J
2016-01-01
Autism is a developmental disability characterized by atypical social interaction, interests or body movements, and communication. Our review examines the empirical status of three communication phenomena believed to be unique to autism: pronoun reversal (using the pronoun you when the pronoun I is intended, and vice versa), echolalia (repeating what someone has said), and a reduced or even reversed production-comprehension lag (a reduction or reversal of the well-established finding that speakers produce less sophisticated language than they can comprehend). Each of these three phenomena has been claimed to be unique to autism; therefore, each has been proposed to be diagnostic of autism, and each has been interpreted in autism-centric ways (psychoanalytic interpretations of pronoun reversal, behaviorist interpretations of echolalia, and clinical lore about the production-comprehension lag). However, as our review demonstrates, none of these three phenomena is in fact unique to autism; none can or should serve as diagnostic of autism, and all call into question unwarranted assumptions about autistic persons and their language development and use.
-
Gernsbacher, Morton Ann; Morson, Emily M.; Grace, Elizabeth J.
2017-01-01
Autism is a developmental disability characterized by atypical social interaction, interests or body movements, and communication. Our review examines the empirical status of three communication phenomena believed to be unique to autism: pronoun reversal (using the pronoun you when the pronoun I is intended, and vice versa), echolalia (repeating what someone has said), and a reduced or even reversed production-comprehension lag (a reduction or reversal of the well-established finding that speakers produce less sophisticated language than they can comprehend). Each of these three phenomena has been claimed to be unique to autism; therefore, each has been proposed to be diagnostic of autism, and each has been interpreted in autism-centric ways (psychoanalytic interpretations of pronoun reversal, behaviorist interpretations of echolalia, and clinical lore about the production-comprehension lag). However, as our review demonstrates, none of these three phenomena is in fact unique to autism; none can or should serve as diagnostic of autism, and all call into question unwarranted assumptions about autistic persons and their language development and use. PMID:28127576
-
Ruan, Sheng-Yuan; Chuang, Yu-Chung; Lin, Jou-Wei; Chien, Jung-Yien; Huang, Chun-Ta; Kuo, Yao-Wen; Lee, Li-Na; Yu, Chong-Jen J
2012-01-01
Background Tuberculous pleurisy is traditionally indicated by extreme lymphocytosis in pleural fluid and low yield of effusion culture. However, there is considerable inconsistency among previous study results. In addition, these data should be updated due to early effusion studies and advances in culture methods. Methods From January 2004 to June 2009, patients with tuberculous pleurisy were retrospectively identified from the mycobacteriology laboratories and the pathology and tuberculosis registration databases of two hospitals in Taiwan where tuberculosis is endemic. Pleural fluid characteristics and yields of mycobacterial cultures using liquid media were evaluated. Results A total of 382 patients with tuberculous pleurisy were identified. The median lymphocyte percentage of total cells in pleural fluids was 84% (IQR 64–95%) and 17% of cases had a lymphocyte percentage of <50%. The lymphocyte percentage was negatively associated with the probability of a positive effusion culture (OR 0.97; 95% CI 0.96 to 0.99). The diagnostic yields were 63% for effusion culture, 48% for sputum culture, 79% for the combination of effusion and sputum cultures, and 74% for histological examination of pleural biopsy specimens. Conclusion The degree of lymphocyte predominance in tuberculous pleurisy was lower than was previously thought. The lymphocyte percentage in pleural fluid was negatively associated with the probability of a positive effusion culture. With the implementation of a liquid culture method, the sensitivity of effusion culture was much higher than has been previously reported, and the combination of effusion and sputum cultures provided a good diagnostic yield. PMID:22436167
-
Electromagnetic Navigation Diagnostic Bronchoscopy
Gildea, Thomas R.; Mazzone, Peter J.; Karnak, Demet; Meziane, Moulay; Mehta, Atul C.
2006-01-01
Rationale: Electromagnetic navigation bronchoscopy using superDimension/Bronchus System is a novel method to increase diagnostic yield of peripheral and mediastinal lung lesions. Objectives: A prospective, open label, single-center, pilot study was conducted to determine the ability of electromagnetic navigation bronchoscopy to sample peripheral lung lesions and mediastinal lymph nodes with standard bronchoscopic instruments and demonstrate safety. Methods: Electromagnetic navigation bronchoscopy was performed using the superDimension/Bronchus system consisting of electromagnetic board, position sensor encapsulated in the tip of a steerable probe, extended working channel, and real-time reconstruction of previously acquired multiplanar computed tomography images. The final distance of the steerable probe to lesion, expected error based on the actual and virtual markers, and procedure yield was gathered. Measurements: 60 subjects were enrolled between December 2004 and September 2005. Mean navigation times were 7 ± 6 min and 2 ± 2 min for peripheral lesions and lymph nodes, respectively. The steerable probe tip was navigated to the target lung area in all cases. The mean peripheral lesions and lymph nodes size was 22.8 ± 12.6 mm and 28.1 ± 12.8 mm. Yield was determined by results obtained during the bronchoscopy per patient. Results: The yield/procedure was 74% and 100% for peripheral lesions and lymph nodes, respectively. A diagnosis was obtained in 80.3% of bronchoscopic procedures. A definitive diagnosis of lung malignancy was made in 74.4% of subjects. Pneumothorax occurred in two subjects. Conclusion: Electromagnetic navigation bronchoscopy is a safe method for sampling peripheral and mediastinal lesions with high diagnostic yield independent of lesion size and location. PMID:16873767
-
Baker, Elizabeth A; Ledford, Cynthia H; Fogg, Louis; Way, David P; Park, Yoon Soo
2015-01-01
Construct: Clinical skills are used in the care of patients, including reporting, diagnostic reasoning, and decision-making skills. Written comprehensive new patient admission notes (H&Ps) are a ubiquitous part of student education but are underutilized in the assessment of clinical skills. The interpretive summary, differential diagnosis, explanation of reasoning, and alternatives (IDEA) assessment tool was developed to assess students' clinical skills using written comprehensive new patient admission notes. The validity evidence for assessment of clinical skills using clinical documentation following authentic patient encounters has not been well documented. Diagnostic justification tools and postencounter notes are described in the literature (1,2) but are based on standardized patient encounters. To our knowledge, the IDEA assessment tool is the first published tool that uses medical students' H&Ps to rate students' clinical skills. The IDEA assessment tool is a 15-item instrument that asks evaluators to rate students' reporting, diagnostic reasoning, and decision-making skills based on medical students' new patient admission notes. This study presents validity evidence in support of the IDEA assessment tool using Messick's unified framework, including content (theoretical framework), response process (interrater reliability), internal structure (factor analysis and internal-consistency reliability), and relationship to other variables. Validity evidence is based on results from four studies conducted between 2010 and 2013. First, the factor analysis (2010, n = 216) yielded a three-factor solution, measuring patient story, IDEA, and completeness, with reliabilities of .79, .88, and .79, respectively. Second, an initial interrater reliability study (2010) involving two raters demonstrated fair to moderate consensus (κ = .21-.56, ρ =.42-.79). Third, a second interrater reliability study (2011) with 22 trained raters also demonstrated fair to moderate agreement (intraclass correlations [ICCs] = .29-.67). There was moderate reliability for all three skill domains, including reporting skills (ICC = .53), diagnostic reasoning skills (ICC = .64), and decision-making skills (ICC = .63). Fourth, there was a significant correlation between IDEA rating scores (2010-2013) and final Internal Medicine clerkship grades (r = .24), 95% confidence interval (CI) [.15, .33]. The IDEA assessment tool is a novel tool with validity evidence to support its use in the assessment of students' reporting, diagnostic reasoning, and decision-making skills. The moderate reliability achieved supports formative or lower stakes summative uses rather than high-stakes summative judgments.
-
NASA Technical Reports Server (NTRS)
Kurth, William S.
1991-01-01
The Plasma Diagnostics Package (PDP) is a spacecraft which was designed and built at The University of Iowa and which contained several scientific instruments. These instruments were used for measuring Space Shuttle Orbiter environmental parameters and plasma parameters. The PDP flew on two Space Shuttle flights. The first flight of the PDP was on Space Shuttle Mission STS-3 and was a part of the NASA/Office of Space Science payload (OSS-1). The second flight of the PDP was on Space Shuttle Mission STS/51F and was a part of Spacelab 2. The interpretation of both the OSS-1 and Spacelab 2 PDP results in terms of large space structure plasma interactions is emphasized.
-
Jieyi Li; Arandjelovic, Ognjen
2017-07-01
Computer science and machine learning in particular are increasingly lauded for their potential to aid medical practice. However, the highly technical nature of the state of the art techniques can be a major obstacle in their usability by health care professionals and thus, their adoption and actual practical benefit. In this paper we describe a software tool which focuses on the visualization of predictions made by a recently developed method which leverages data in the form of large scale electronic records for making diagnostic predictions. Guided by risk predictions, our tool allows the user to explore interactively different diagnostic trajectories, or display cumulative long term prognostics, in an intuitive and easily interpretable manner.
-
FDG-PET improves accuracy in distinguishing frontotemporal dementia and Alzheimer's disease.
Foster, Norman L; Heidebrink, Judith L; Clark, Christopher M; Jagust, William J; Arnold, Steven E; Barbas, Nancy R; DeCarli, Charles S; Turner, R Scott; Koeppe, Robert A; Higdon, Roger; Minoshima, Satoshi
2007-10-01
Distinguishing Alzheimer's disease (AD) and frontotemporal dementia (FTD) currently relies on a clinical history and examination, but positron emission tomography with [(18)F] fluorodeoxyglucose (FDG-PET) shows different patterns of hypometabolism in these disorders that might aid differential diagnosis. Six dementia experts with variable FDG-PET experience made independent, forced choice, diagnostic decisions in 45 patients with pathologically confirmed AD (n = 31) or FTD (n = 14) using five separate methods: (1) review of clinical summaries, (2) a diagnostic checklist alone, (3) summary and checklist, (4) transaxial FDG-PET scans and (5) FDG-PET stereotactic surface projection (SSP) metabolic and statistical maps. In addition, we evaluated the effect of the sequential review of a clinical summary followed by SSP. Visual interpretation of SSP images was superior to clinical assessment and had the best inter-rater reliability (mean kappa = 0.78) and diagnostic accuracy (89.6%). It also had the highest specificity (97.6%) and sensitivity (86%), and positive likelihood ratio for FTD (36.5). The addition of FDG-PET to clinical summaries increased diagnostic accuracy and confidence for both AD and FTD. It was particularly helpful when raters were uncertain in their clinical diagnosis. Visual interpretation of FDG-PET after brief training is more reliable and accurate in distinguishing FTD from AD than clinical methods alone. FDG-PET adds important information that appropriately increases diagnostic confidence, even among experienced dementia specialists.
-
Ghadri, Jelena-Rima; Wittstein, Ilan Shor; Prasad, Abhiram; Sharkey, Scott; Dote, Keigo; Akashi, Yoshihiro John; Cammann, Victoria Lucia; Crea, Filippo; Galiuto, Leonarda; Desmet, Walter; Yoshida, Tetsuro; Manfredini, Roberto; Eitel, Ingo; Kosuge, Masami; Nef, Holger M; Deshmukh, Abhishek; Lerman, Amir; Bossone, Eduardo; Citro, Rodolfo; Ueyama, Takashi; Corrado, Domenico; Kurisu, Satoshi; Ruschitzka, Frank; Winchester, David; Lyon, Alexander R; Omerovic, Elmir; Bax, Jeroen J; Meimoun, Patrick; Tarantini, Guiseppe; Rihal, Charanjit; Y-Hassan, Shams; Migliore, Federico; Horowitz, John D; Shimokawa, Hiroaki; Lüscher, Thomas Felix; Templin, Christian
2018-06-07
The clinical expert consensus statement on takotsubo syndrome (TTS) part II focuses on the diagnostic workup, outcome, and management. The recommendations are based on interpretation of the limited clinical trial data currently available and experience of international TTS experts. It summarizes the diagnostic approach, which may facilitate correct and timely diagnosis. Furthermore, the document covers areas where controversies still exist in risk stratification and management of TTS. Based on available data the document provides recommendations on optimal care of such patients for practising physicians.
-
Ghadri, Jelena-Rima; Wittstein, Ilan Shor; Prasad, Abhiram; Sharkey, Scott; Dote, Keigo; Akashi, Yoshihiro John; Cammann, Victoria Lucia; Crea, Filippo; Galiuto, Leonarda; Desmet, Walter; Yoshida, Tetsuro; Manfredini, Roberto; Eitel, Ingo; Kosuge, Masami; Nef, Holger M; Deshmukh, Abhishek; Lerman, Amir; Bossone, Eduardo; Citro, Rodolfo; Ueyama, Takashi; Corrado, Domenico; Kurisu, Satoshi; Ruschitzka, Frank; Winchester, David; Lyon, Alexander R; Omerovic, Elmir; Bax, Jeroen J; Meimoun, Patrick; Tarantini, Guiseppe; Rihal, Charanjit; Y.-Hassan, Shams; Migliore, Federico; Horowitz, John D; Shimokawa, Hiroaki; Lüscher, Thomas Felix; Templin, Christian
2018-01-01
Abstract The clinical expert consensus statement on takotsubo syndrome (TTS) part II focuses on the diagnostic workup, outcome, and management. The recommendations are based on interpretation of the limited clinical trial data currently available and experience of international TTS experts. It summarizes the diagnostic approach, which may facilitate correct and timely diagnosis. Furthermore, the document covers areas where controversies still exist in risk stratification and management of TTS. Based on available data the document provides recommendations on optimal care of such patients for practising physicians. PMID:29850820
-
Rossi, Mari; El-Khechen, Dima; Black, Mary Helen; Farwell Hagman, Kelly D; Tang, Sha; Powis, Zöe
2017-05-01
Exome sequencing has recently been proved to be a successful diagnostic method for complex neurodevelopmental disorders. However, the diagnostic yield of exome sequencing for autism spectrum disorders has not been extensively evaluated in large cohorts to date. We performed diagnostic exome sequencing in a cohort of 163 individuals with autism spectrum disorder (66.3%) or autistic features (33.7%). The diagnostic yield observed in patients in our cohort was 25.8% (42 of 163) for positive or likely positive findings in characterized disease genes, while a candidate genetic etiology was reported for an additional 3.3% (4 of 120) of patients. Among the positive findings in the patients with autism spectrum disorder or autistic features, 61.9% were the result of de novo mutations. Patients presenting with psychiatric conditions or ataxia or paraplegia in addition to autism spectrum disorder or autistic features were significantly more likely to receive positive results compared with patients without these clinical features (95.6% vs 27.1%, P < 0.0001; 83.3% vs 21.2%, P < 0.0001, respectively). The majority of the positive findings were in recently identified autism spectrum disorder genes, supporting the importance of diagnostic exome sequencing for patients with autism spectrum disorder or autistic features as the causative genes might evade traditional sequential or panel testing. These results suggest that diagnostic exome sequencing would be an efficient primary diagnostic method for patients with autism spectrum disorders or autistic features. Moreover, our data may aid clinicians to better determine which subset of patients with autism spectrum disorder with additional clinical features would benefit the most from diagnostic exome sequencing. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
-
Design of a Neutron Temporal Diagnostic for measuring DD or DT burn histories at the NIF
NASA Astrophysics Data System (ADS)
Lahmann, B.; Frenje, J. A.; Sio, H.; Petrasso, R. D.; Bradley, D. K.; Le Pape, S.; MacKinnon, A. J.; Isumi, N.; Macphee, A.; Zayas, C.; Spears, B. K.; Hermann, H.; Hilsabeck, T. J.; Kilkenny, J. D.
2015-11-01
The DD or DT burn history in Inertial Confinement Fusion (ICF) implosions provides essential information about implosion performance and helps to constrain numerical modeling. The capability of measuring this burn history is thus important for the NIF in its pursuit of ignition. Currently, the Gamma Reaction History (GRH) diagnostic is the only system capable of measuring the burn history for DT implosions with yields greater than ~ 1e14. To complement GRH, a new NIF Neutron Temporal Diagnostic (NTD) is being designed for measuring the DD or DT burn history with yields greater than ~ 1e10. A traditional scintillator-based design and a pulse-dilation-based design are being considered. Using MCNPX simulations, both designs have been optimized, validated and contrasted for various types of implosions at the NIF. This work was supported in part by the U.S. DOE, LLNL and LLE.
-
Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hatarik, R., E-mail: hatarik1@llnl.gov; Sayre, D. B.; Caggiano, J. A.
2015-11-14
Neutron time-of-flight diagnostics have long been used to characterize the neutron spectrum produced by inertial confinement fusion experiments. The primary diagnostic goals are to extract the d + t → n + α (DT) and d + d → n + {sup 3}He (DD) neutron yields and peak widths, and the amount DT scattering relative to its unscattered yield, also known as the down-scatter ratio (DSR). These quantities are used to infer yield weighted plasma conditions, such as ion temperature (T{sub ion}) and cold fuel areal density. We report on novel methodologies used to determine neutron yield, apparent T{sub ion}, and DSR. These methods invoke a single temperature,more » static fluid model to describe the neutron peaks from DD and DT reactions and a spline description of the DT spectrum to determine the DSR. Both measurements are performed using a forward modeling technique that includes corrections for line-of-sight attenuation and impulse response of the detection system. These methods produce typical uncertainties for DT T{sub ion} of 250 eV, 7% for DSR, and 9% for the DT neutron yield. For the DD values, the uncertainties are 290 eV for T{sub ion} and 10% for the neutron yield.« less
-
Deming, Damon J; Patel, Nita; McCarthy, Michael P; Mishra, Lalji; Shapiro, Alan M; Suzich, JoAnn A
2013-10-01
Palivizumab is a monoclonal antibody indicated for the prevention of serious lower respiratory tract disease caused by respiratory syncytial virus infection in infants. The potential for palivizumab to interfere with commercially available respiratory syncytial virus diagnostic tests was demonstrated. Negative test results in palivizumab-treated subjects should be interpreted with caution and confirmed by a nucleic acid amplification-based assay.
-
ERIC Educational Resources Information Center
Galanter, Cathryn A.; Hundt, Stephanie R.; Goyal, Parag; Le, Jenna; Fisher, Prudence W.
2012-01-01
Objective: The "DSM-IV-TR "criteria for a manic episode and bipolar disorder (BD) were developed for adults but are used for children. The manner in which clinicians and researchers interpret these criteria may have contributed to the increase in BD diagnoses given to youth. Research interviews are designed to improve diagnostic reliability and…
-
ERIC Educational Resources Information Center
Gebhardt, Markus; Krammer, Mathias; Schwab, Susanne; Rossmann, Peter; Klicpera, Barbara Gasteiger; Klatten, Susanne
2013-01-01
Every school system has to deal with children with Learning Disabilities (LD). However, the concepts of LD, the assessment procedures, the diagnostic criteria as well as their interpretation vary widely from country to country. What they usually seem to have in common is that general cognitive abilities, as measured by standardized IQ tests, are…
-
ERIC Educational Resources Information Center
Ruscio, John; Brown, Timothy A.; Ruscio, Ayelet Meron
2009-01-01
Most taxometric studies of depressive constructs have drawn indicators from self-report instruments that do not bear directly on the "Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV)" diagnostic construct of major depressive disorder (MDD). The present study examined the latent structure of MDD using indicator sets…
-
ERIC Educational Resources Information Center
Gebhardt, Markus; Krammer, Mathias; Schwab, Susanne; Rossmann, Peter; Gasteiger Klicpera, Barbara
2013-01-01
Every school system has to deal with children with Learning Disabilities (LD). However, the concepts of LD, the assessment procedures, the diagnostic criteria as well as their interpretation vary widely from country to country. What they usually have in common is that general cognitive abilities, as measured by standardized IQ tests, are seen as…
-
Casey, R; Griffin, T P; Wall, D; Dennedy, M C; Bell, M; O'Shea, P M
2017-01-01
Background The Endocrine Society Clinical Practice Guideline on Phaeochomocytoma and Paraganglioma recommends phlebotomy for plasma-free metanephrines with patients fasted and supine using appropriately defined reference intervals. Studies have shown higher diagnostic sensitivities using these criteria. Further, with seated-sampling protocols, for result interpretation, reference intervals that do not compromise diagnostic sensitivity should be employed. Objective To determine the impact on diagnostic performance and financial cost of using supine reference intervals for result interpretation with our current plasma-free metanephrines fasted/seated-sampling protocol. Methods We conducted a retrospective cohort study of patients who underwent screening for PPGL using plasma-free metanephrines from 2009 to 2014 at Galway University Hospitals. Plasma-free metanephrines were measured using liquid chromatography-tandem mass spectrometry. Supine thresholds for plasma normetanephrine and metanephrine set at 610 pmol/L and 310 pmol/L, respectively, were used. Results A total of 183 patients were evaluated. Mean age of participants was 53.4 (±16.3) years. Five of 183 (2.7%) patients had histologically confirmed PPGL (males, n=4). Using seated reference intervals for plasma-free metanephrines, diagnostic sensitivity and specificity were 100% and 98.9%, respectively, with two false-positive cases. Application of reference intervals established in subjects supine and fasted to this cohort gave diagnostic sensitivity of 100% with specificity of 74.7%. Financial analysis of each pretesting strategy demonstrated cost-equivalence (€147.27/patient). Conclusion Our cost analysis, together with the evidence that fasted/supine-sampling for plasma-free metanephrines, offers more reliable exclusion of PPGL mandates changing our current practice. This study highlights the important advantages of standardized diagnostic protocols for plasma-free metanephrines to ensure the highest diagnostic accuracy for investigation of PPGL.
-
A WAO - ARIA - GA²LEN consensus document on molecular-based allergy diagnostics
2013-01-01
Molecular-based allergy (MA) diagnostics is an approach used to map the allergen sensitization of a patient at a molecular level, using purified natural or recombinant allergenic molecules (allergen components) instead of allergen extracts. Since its introduction, MA diagnostics has increasingly entered routine care, with currently more than 130 allergenic molecules commercially available for in vitro specific IgE (sIgE) testing. MA diagnostics allows for an increased accuracy in allergy diagnosis and prognosis and plays an important role in three key aspects of allergy diagnosis: (1) resolving genuine versus cross-reactive sensitization in poly-sensitized patients, thereby improving the understanding of triggering allergens; (2) assessing, in selected cases, the risk of severe, systemic versus mild, local reactions in food allergy, thereby reducing unnecessary anxiety for the patient and the need for food challenge testing; and (3) identifying patients and triggering allergens for specific immunotherapy (SIT). Singleplex and multiplex measurement platforms are available for MA diagnostics. The Immuno-Solid phase Allergen Chip (ISAC) is the most comprehensive platform currently available, which involves a biochip technology to measure sIgE antibodies against more than one hundred allergenic molecules in a single assay. As the field of MA diagnostics advances, future work needs to focus on large-scale, population-based studies involving practical applications, elucidation and expansion of additional allergenic molecules, and support for appropriate test interpretation. With the rapidly expanding evidence-base for MA diagnosis, there is a need for allergists to keep abreast of the latest information. The aim of this consensus document is to provide a practical guide for the indications, determination, and interpretation of MA diagnostics for clinicians trained in allergology. PMID:24090398
-
A WAO - ARIA - GA²LEN consensus document on molecular-based allergy diagnostics.
Canonica, Giorgio Walter; Ansotegui, Ignacio J; Pawankar, Ruby; Schmid-Grendelmeier, Peter; van Hage, Marianne; Baena-Cagnani, Carlos E; Melioli, Giovanni; Nunes, Carlos; Passalacqua, Giovanni; Rosenwasser, Lanny; Sampson, Hugh; Sastre, Joaquin; Bousquet, Jean; Zuberbier, Torsten
2013-10-03
Molecular-based allergy (MA) diagnostics is an approach used to map the allergen sensitization of a patient at a molecular level, using purified natural or recombinant allergenic molecules (allergen components) instead of allergen extracts. Since its introduction, MA diagnostics has increasingly entered routine care, with currently more than 130 allergenic molecules commercially available for in vitro specific IgE (sIgE) testing.MA diagnostics allows for an increased accuracy in allergy diagnosis and prognosis and plays an important role in three key aspects of allergy diagnosis: (1) resolving genuine versus cross-reactive sensitization in poly-sensitized patients, thereby improving the understanding of triggering allergens; (2) assessing, in selected cases, the risk of severe, systemic versus mild, local reactions in food allergy, thereby reducing unnecessary anxiety for the patient and the need for food challenge testing; and (3) identifying patients and triggering allergens for specific immunotherapy (SIT).Singleplex and multiplex measurement platforms are available for MA diagnostics. The Immuno-Solid phase Allergen Chip (ISAC) is the most comprehensive platform currently available, which involves a biochip technology to measure sIgE antibodies against more than one hundred allergenic molecules in a single assay. As the field of MA diagnostics advances, future work needs to focus on large-scale, population-based studies involving practical applications, elucidation and expansion of additional allergenic molecules, and support for appropriate test interpretation. With the rapidly expanding evidence-base for MA diagnosis, there is a need for allergists to keep abreast of the latest information. The aim of this consensus document is to provide a practical guide for the indications, determination, and interpretation of MA diagnostics for clinicians trained in allergology.
-
Xu, Bai-xuan; Liu, Chang-bin; Wang, Rui-min; Shao, Ming-zhe; Fu, Li-ping; Li, Yun-gang; Tian, Jia-he
2013-01-01
Based on the results of a recently accomplished multicenter clinical trial for the incremental value of a dual-tracer (18F-FDG and 18F-FLT), dual-modality (PET and CT) imaging in the differential diagnosis of pulmonary lesions, we investigate some issues that might affect the image interpretation and result reporting. The images were read in two separate sessions. Firstly the images were read and reported by physician(s) of the imaging center on completion of each PET/CT scanning. By the end of MCCT, all images collected during the trial were re-read by a collective of readers in an isolated, blinded, and independent way. One hundred sixty two patients successfully passed the data verification and entered into the final analysis. The primary reporting result showed adding 18F-FDG image information did not change the clinical performance much in sensitivity, specifity and accuracy, but the ratio between SUVFLT and SUVFDG did help the differentiation efficacy among the three subgroups of patients. The collective reviewing result showed the diagnostic achievement varied with reading strategies. ANOVA indicated significant differences among (18)F-FDG, (18)F-FLT in SUV (F = 14.239, p = 0.004). CT had almost the same diagnostic performance as 18F-FLT. When the 18F-FDG, 18F-FLT and CT images read in pair, both diagnostic sensitivity and specificity improved. The best diagnostic figures were obtained in full-modality strategy, when dual-tracer PET worked in combination with CT. With certain experience and training both radiologists and nuclear physicians are qualified to read and to achieve the similar diagnostic accuracy in PET/CT study. Making full use of modality combination and selecting right criteria seems more practical than professional back ground and personal experience in the new hybrid imaging technology, at least when novel tracer or application is concerned.
-
Walsworth, Matthew K; Doukas, William C; Murphy, Kevin P; Mielcarek, Billie J; Michener, Lori A
2008-01-01
Glenoid labral tears provide a diagnostic challenge. Combinations of items in the patient history and physical examination will provide stronger diagnostic accuracy to suggest the presence or absence of glenoid labral tear than will individual items. Cohort study (diagnosis); Level of evidence, 1. History and examination findings in patients with shoulder pain (N = 55) were compared with arthroscopic findings to determine diagnostic accuracy and intertester reliability. The intertester reliability of the crank, anterior slide, and active compression tests was 0.20 to 0.24. A combined history of popping or catching and positive crank or anterior slide results yielded specificities of 0.91 and 1.00 and positive likelihood ratios of 3.0 and infinity, respectively. A positive anterior slide result combined with either a positive active compression or crank result yielded specificities of 0.91 and positive likelihood ratio of 2.75 and 3.75, respectively. Requiring only a single positive finding in the combination of popping or catching and the anterior slide or crank yielded sensitivities of 0.82 and 0.89 and negative likelihood ratios of 0.31 and 0.33, respectively. The diagnostic accuracy of individual tests in previous studies is quite variable, which may be explained in part by the modest reliability of these tests. The combination of popping or catching with a positive crank or anterior slide result or a positive anterior slide result with a positive active compression or crank test result suggests the presence of a labral tear. The combined absence of popping or catching and a negative anterior slide or crank result suggests the absence of a labral tear.
-
Determination of diagnostic standards on saturated soil extracts for cut roses grown in greenhouses.
Franco-Hermida, John Jairo; Quintero, María Fernanda; Cabrera, Raúl Iskander; Guzman, José Miguel
2017-01-01
This work comprises the theoretical determination and validation of diagnostic standards for the analysis of saturated soil extracts for cut rose flower crops (Rosa spp.) growing in the Bogota Plateau, Colombia. The data included 684 plant tissue analyses and 684 corresponding analyses of saturated soil extracts, all collected between January 2009 and June 2013. The tissue and soil samples were selected from 13 rose farms, and from cultivars grafted on the 'Natal Briar' rootstock. These concurrent samples of soil and plant tissues represented 251 production units (locations) of approximately 10,000 m2 distributed across the study area. The standards were conceived as a tool to improve the nutritional balance in the leaf tissue of rose plants and thereby define the norms for expressing optimum productive potential relative to nutritional conditions in the soil. To this end, previously determined diagnostic standard for rose leaf tissues were employed to obtain rates of foliar nutritional balance at each analyzed location and as criteria for determining the diagnostic norms for saturated soil extracts. Implementing this methodology to foliar analysis, showed a higher significant correlation for diagnostic indices. A similar behavior was observed in saturated soil extracts analysis, becoming a powerful tool for integrated nutritional diagnosis. Leaf analyses determine the most limiting nutrients for high yield and analyses of saturated soil extracts facilitate the possibility of correcting the fertigation formulations applied to soils or substrates. Recommendations are proposed to improve the balance in soil-plant system with which the possibility of yield increase becomes more probable. The main recommendations to increase and improve rose crop flower yields would be: continuously check pH values of SSE, reduce the amounts of P, Fe, Zn and Cu in fertigation solutions and carefully analyze the situation of Mn in the soil-plant system.
-
Guldbrandt, Louise Mahncke; Fenger-Grøn, Morten; Rasmussen, Torben Riis; Jensen, Henry; Vedsted, Peter
2015-01-22
Lung cancer stage at diagnosis predicts possible curative treatment. In Denmark and the UK, lung cancer patients have lower survival rates than citizens in most other European countries, which may partly be explained by a comparatively longer diagnostic interval in these two countries. In Denmark, a pathway was introduced in 2008 allowing general practitioners (GPs) to refer patients suspected of having lung cancer directly to fast-track diagnostics. However, symptom presentation of lung cancer in general practice is known to be diverse and complex, and systematic knowledge of the routes to diagnosis is needed to enable earlier lung cancer diagnosis in Denmark. This study aims to describe the routes to diagnosis, the diagnostic activity preceding diagnosis and the diagnostic intervals for lung cancer in the Danish setting. We conducted a national registry-based cohort study on 971 consecutive incident lung cancer patients in 2010 using data from national registries and GP questionnaires. GPs were involved in 68.3% of cancer patients' diagnostic pathways, and 27.4% of lung cancer patients were referred from the GP to fast-track diagnostic work-up. A minimum of one X-ray was performed in 85.6% of all cases before diagnosis. Patients referred through a fast-track route more often had diagnostic X-rays (66.0%) than patients who did not go through fast-track (49.4%). Overall, 33.6% of all patients had two or more X-rays performed during the 90 days before diagnosis. Patients whose symptoms were interpreted as non-alarm symptoms or who were not referred to fast-track were more likely to experience a long diagnostic interval than patients whose symptoms were interpreted as alarm symptoms or who were referred to fast-track. Lung cancer patients followed several diagnostic pathways. The existing fast-track pathway must be supplemented to ensure earlier detection of lung cancer. The high incidence of multiple X-rays warrants a continued effort to develop more accurate lung cancer tests for use in primary care.
-
Impact of Coronary Calcification on Clinical Management in Patients With Acute Chest Pain
Bittner, Daniel O.; Mayrhofer, Thomas; Bamberg, Fabian; Hallett, Travis R.; Janjua, Sumbal; Addison, Daniel; Nagurney, John T.; Udelson, James E.; Lu, Michael T.; Truong, Quynh A.; Woodard, Pamela K.; Hollander, Judd E.; Miller, Chadwick; Chang, Anna Marie; Singh, Harjit; Litt, Harold; Hoffmann, Udo; Ferencik, Maros
2018-01-01
Background Coronary artery calcification (CAC) may impair diagnostic assessment of coronary computed tomography angiography (CTA). We determined whether CAC affects efficiency of coronary CTA in patients with suspected acute coronary syndrome (ACS). Methods and Results This is a pooled analysis of ACRIN-PA-4005 and ROMICAT-II trial comparing an initial coronary CTA strategy to standard of care in acute chest pain patients. In the CTA arms, we investigated appropriateness of downstream testing, cost and diagnostic yield to identify patients with obstructive coronary artery disease (CAD) on subsequent invasive coronary angiography (ICA) across CAC score strata (Agatston score: 0, >0–10, >10–100, >100–400, >400). Out of 1,234 patients (mean age 51±8.8 years), 80 (6.5%) had obstructive CAD (≥70% stenosis), and 68 (5.5%) had ACS. Prevalence of obstructive CAD (1% to 64%), ACS (1% to 44%), downstream testing (4% to 72%), total (2337 US$ to 8484 US$) and diagnostic cost (2310 US$ to 6678 US$) increased across CAC strata (p<0.001). As the increase in testing and cost were lower than the increase of ACS rate in patients with CAC>400, cost to diagnose one ACS was lowest in this group (19,283 US$ vs. 464,399 US$) as compared to patients without CAC. The diagnostic yield of ICA was highest in patients with CAC>400 (87% vs. 38%). Conclusion Downstream testing, total and diagnostic cost increased with increasing CAC, but were found to be appropriate, as obstructive CAD and ACS were more prevalent in patients with high CAC. In patients with acute chest pain undergoing coronary CTA, cost efficient testing and excellent diagnostic yield can be achieved even with high CAC burden. Clinical Trial Registration Information URL: https://clinicaltrials.gov. Unique identifier: NCT01084239 and NCT00933400. PMID:28487318
-
Diken, Özlem E; Karnak, Demet; Çiledağ, Aydın; Ceyhan, Koray; Atasoy, Çetin; Akyar, Serdar; Kayacan, Oya
2015-04-01
Conventional transbronchial needle aspiration (C-TBNA) is a safe method for the diagnosis of hilar and mediastinal lymphadenopathy (MLN). However, diagnostic yield of this technique varies considerably. Electromagnetic navigation bronchoscopy (ENB) is a new technology to increase the diagnostic yield of flexible bronchoscopy for the peripheral lung lesions and MLN. The aim of this prospective study was to compare the diagnostic and sampling success of ENB-guided TBNA (ENB-TBNA) in comparison with C-TBNA while dealing with MLN. Consecutive patients with MLN were randomized into two groups - C-TBNA and ENB-TBNA - using a computer-based number shuffling system to avoid recruitment bias. Procedures were performed in usual fashion, published previously. Ninety-four cases (M/F: 45/49) with a total of 145 stations of MLN were enrolled in the study. In 44 patients, 81 stations were sampled by ENB-TBNA, and in 50 patients 64 stations by C-TBNA. The mean size of MLN in study subjects was 17.56 ± 6.25 mm. The sampling success was significantly higher in ENB-TBNA group (82.7%) compared with C-TBNA group (51.6%) (P < 0.005). Defined by histopathological result, the diagnostic yield in ENB-TBNA was 72.8%, and 42.2% with C-TBNA (P < 0.005). For subcarinal localization, sampling or diagnostic success was higher in ENB-TBNA than that of C-TBNA (P < 0.05). Based on the size of the MLN ≤15 mm or >15 mm, the sampling success of ENB-TBNA was also significantly higher than C-TBNA in both subgroups (P < 0.005 and P < 0.005, respectively). No serious complication was observed. In this study comparing ENB-TBNA and C-TBNA, the sampling and diagnostic success of ENB-TBNA was found to be superior while dealing with MLN, in all categories studied. © 2014 John Wiley & Sons Ltd.
-
Labourier, Emmanuel; Shifrin, Alexander; Busseniers, Anne E; Lupo, Mark A; Manganelli, Monique L; Andruss, Bernard; Wylie, Dennis; Beaudenon-Huibregtse, Sylvie
2015-07-01
Molecular testing for oncogenic mutations or gene expression in fine-needle aspirations (FNAs) from thyroid nodules with indeterminate cytology identifies a subset of benign or malignant lesions with high predictive value. This study aimed to evaluate a novel diagnostic algorithm combining mutation detection and miRNA expression to improve the diagnostic yield of molecular cytology. Surgical specimens and preoperative FNAs (n = 638) were tested for 17 validated gene alterations using the miRInform Thyroid test and with a 10-miRNA gene expression classifier generating positive (malignant) or negative (benign) results. Cross-sectional sampling of thyroid nodules with atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) or follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN) cytology (n = 109) was conducted at 12 endocrinology centers across the United States. Qualitative molecular results were compared with surgical histopathology to determine diagnostic performance and model clinical effect. Mutations were detected in 69% of nodules with malignant outcome. Among mutation-negative specimens, miRNA testing correctly identified 64% of malignant cases and 98% of benign cases. The diagnostic sensitivity and specificity of the combined algorithm was 89% (95% confidence interval [CI], 73-97%) and 85% (95% CI, 75-92%), respectively. At 32% cancer prevalence, 61% of the molecular results were benign with a negative predictive value of 94% (95% CI, 85-98%). Independently of variations in cancer prevalence, the test increased the yield of true benign results by 65% relative to mRNA-based gene expression classification and decreased the rate of avoidable diagnostic surgeries by 69%. Multiplatform testing for DNA, mRNA, and miRNA can accurately classify benign and malignant thyroid nodules, increase the diagnostic yield of molecular cytology, and further improve the preoperative risk-based management of benign nodules with AUS/FLUS or FN/SFN cytology.
-
Codetype-based interpretation of the MMPI-2 in an outpatient psychotherapy sample.
Koffmann, Andrew
2015-01-01
In an evaluation of the codetype-based interpretation of the MMPI-2, 48 doctoral student psychotherapists rated their clients' (N = 120) standardized interpretations as more accurate when based on the profile's codetype, in comparison with ratings for interpretations based on alternate codetypes. Effect sizes ranged from nonsignificant to large, depending on the degree of proximity between the profile's codetype and the alternate codetype. There was weak evidence to suggest that well-defined profiles yielded more accurate interpretations than undefined profiles. It appears that codetype-based interpretation of the MMPI-2 is generally valid, but there might be little difference in the accuracy of interpretations based on nearby codetypes.
-
Peng, Jin-Min; Qian, Chuan-Yun; Yu, Xiang-You; Zhao, Ming-Yan; Li, Shu-Sheng; Ma, Xiao-Chun; Kang, Yan; Zhou, Fa-Chun; He, Zhen-Yang; Qin, Tie-He; Yin, Yong-Jie; Jiang, Li; Hu, Zhen-Jie; Sun, Ren-Hua; Lin, Jian-Dong; Li, Tong; Wu, Da-Wei; An, You-Zhong; Ai, Yu-Hang; Zhou, Li-Hua; Cao, Xiang-Yuan; Zhang, Xi-Jing; Sun, Rong-Qing; Chen, Er-Zhen; Du, Bin
2017-01-20
Poor inter-rater reliability in chest radiograph interpretation has been reported in the context of acute respiratory distress syndrome (ARDS), although not for the Berlin definition of ARDS. We sought to examine the effect of training material on the accuracy and consistency of intensivists' chest radiograph interpretations for ARDS diagnosis. We conducted a rater agreement study in which 286 intensivists (residents 41.3%, junior attending physicians 35.3%, and senior attending physician 23.4%) independently reviewed the same 12 chest radiographs developed by the ARDS Definition Task Force ("the panel") before and after training. Radiographic diagnoses by the panel were classified into the consistent (n = 4), equivocal (n = 4), and inconsistent (n = 4) categories and were used as a reference. The 1.5-hour training course attended by all 286 intensivists included introduction of the diagnostic rationale, and a subsequent in-depth discussion to reach consensus for all 12 radiographs. Overall diagnostic accuracy, which was defined as the percentage of chest radiographs that were interpreted correctly, improved but remained poor after training (42.0 ± 14.8% before training vs. 55.3 ± 23.4% after training, p < 0.001). Diagnostic sensitivity and specificity improved after training for all diagnostic categories (p < 0.001), with the exception of specificity for the equivocal category (p = 0.883). Diagnostic accuracy was higher for the consistent category than for the inconsistent and equivocal categories (p < 0.001). Comparisons of pre-training and post-training results revealed that inter-rater agreement was poor and did not improve after training, as assessed by overall agreement (0.450 ± 0.406 vs. 0.461 ± 0.575, p = 0.792), Fleiss's kappa (0.133 ± 0.575 vs. 0.178 ± 0.710, p = 0.405), and intraclass correlation coefficient (ICC; 0.219 vs. 0.276, p = 0.470). The radiographic diagnostic accuracy and inter-rater agreement were poor when the Berlin radiographic definition was used, and were not significantly improved by the training set of chest radiographs developed by the ARDS Definition Task Force. The study was registered at ClinicalTrials.gov (registration number NCT01704066 ) on 6 October 2012.
-
NASA Astrophysics Data System (ADS)
Biswas, A.; Sharma, S. P.
2012-12-01
Self-Potential anomaly is an important geophysical technique that measures the electrical potential due natural source of current in the Earth's subsurface. An inclined sheet type model is a very familiar structure associated with mineralization, fault plane, groundwater flow and many other geological features which exhibits self potential anomaly. A number of linearized and global inversion approaches have been developed for the interpretation of SP anomaly over different structures for various purposes. Mathematical expression to compute the forward response over a two-dimensional dipping sheet type structures can be described in three different ways using five variables in each case. Complexities in the inversion using three different forward approaches are different. Interpretation of self-potential anomaly using very fast simulated annealing global optimization has been developed in the present study which yielded a new insight about the uncertainty and equivalence in model parameters. Interpretation of the measured data yields the location of the causative body, depth to the top, extension, dip and quality of the causative body. In the present study, a comparative performance of three different forward approaches in the interpretation of self-potential anomaly is performed to assess the efficacy of the each approach in resolving the possible ambiguity. Even though each forward formulation yields the same forward response but optimization of different sets of variable using different forward problems poses different kinds of ambiguity in the interpretation. Performance of the three approaches in optimization has been compared and it is observed that out of three methods, one approach is best and suitable for this kind of study. Our VFSA approach has been tested on synthetic, noisy and field data for three different methods to show the efficacy and suitability of the best method. It is important to use the forward problem in the optimization that yields the best result without any ambiguity and smaller uncertainty. Keywords: SP anomaly, inclined sheet, 2D structure, forward problems, VFSA Optimization,
-
Lessons learned from additional research analyses of unsolved clinical exome cases.
Eldomery, Mohammad K; Coban-Akdemir, Zeynep; Harel, Tamar; Rosenfeld, Jill A; Gambin, Tomasz; Stray-Pedersen, Asbjørg; Küry, Sébastien; Mercier, Sandra; Lessel, Davor; Denecke, Jonas; Wiszniewski, Wojciech; Penney, Samantha; Liu, Pengfei; Bi, Weimin; Lalani, Seema R; Schaaf, Christian P; Wangler, Michael F; Bacino, Carlos A; Lewis, Richard Alan; Potocki, Lorraine; Graham, Brett H; Belmont, John W; Scaglia, Fernando; Orange, Jordan S; Jhangiani, Shalini N; Chiang, Theodore; Doddapaneni, Harsha; Hu, Jianhong; Muzny, Donna M; Xia, Fan; Beaudet, Arthur L; Boerwinkle, Eric; Eng, Christine M; Plon, Sharon E; Sutton, V Reid; Gibbs, Richard A; Posey, Jennifer E; Yang, Yaping; Lupski, James R
2017-03-21
Given the rarity of most single-gene Mendelian disorders, concerted efforts of data exchange between clinical and scientific communities are critical to optimize molecular diagnosis and novel disease gene discovery. We designed and implemented protocols for the study of cases for which a plausible molecular diagnosis was not achieved in a clinical genomics diagnostic laboratory (i.e. unsolved clinical exomes). Such cases were recruited to a research laboratory for further analyses, in order to potentially: (1) accelerate novel disease gene discovery; (2) increase the molecular diagnostic yield of whole exome sequencing (WES); and (3) gain insight into the genetic mechanisms of disease. Pilot project data included 74 families, consisting mostly of parent-offspring trios. Analyses performed on a research basis employed both WES from additional family members and complementary bioinformatics approaches and protocols. Analysis of all possible modes of Mendelian inheritance, focusing on both single nucleotide variants (SNV) and copy number variant (CNV) alleles, yielded a likely contributory variant in 36% (27/74) of cases. If one includes candidate genes with variants identified within a single family, a potential contributory variant was identified in a total of ~51% (38/74) of cases enrolled in this pilot study. The molecular diagnosis was achieved in 30/63 trios (47.6%). Besides this, the analysis workflow yielded evidence for pathogenic variants in disease-associated genes in 4/6 singleton cases (66.6%), 1/1 multiplex family involving three affected siblings, and 3/4 (75%) quartet families. Both the analytical pipeline and the collaborative efforts between the diagnostic and research laboratories provided insights that allowed recent disease gene discoveries (PURA, TANGO2, EMC1, GNB5, ATAD3A, and MIPEP) and increased the number of novel genes, defined in this study as genes identified in more than one family (DHX30 and EBF3). An efficient genomics pipeline in which clinical sequencing in a diagnostic laboratory is followed by the detailed reanalysis of unsolved cases in a research environment, supplemented with WES data from additional family members, and subject to adjuvant bioinformatics analyses including relaxed variant filtering parameters in informatics pipelines, can enhance the molecular diagnostic yield and provide mechanistic insights into Mendelian disorders. Implementing these approaches requires collaborative clinical molecular diagnostic and research efforts.
-
Talamo, Thomas S.; Losos, Frank J.; Mercer, Donald W.
1984-01-01
We have developed a microcomputer based system for interpretative reporting of creatine kinase (CK) and lactate dehydrogenase (LDH) isoenzyme studies. Patient demographic data and test results (total CK, CK-MB, LD-1, and LD-2) are entered manually through the keyboard. The test results are compared with normal range values and an interpretative report is generated. This report consists of all pertinent demographic information with a graphic display of up to 12 previous CK and LDH isoenzyme determinations. Diagnostic interpretative statements are printed beneath the graphic display following analysis of previously entered test results. The combination of graphic data display and interpretations based on analysis of up to 12 previous specimens provides useful and accurate information to the cardiologist.
-
Incorporation of a clinical history into the interpretation process in a PACS environment
NASA Astrophysics Data System (ADS)
Cooperstein, Lawrence A.; Good, Barbara C.; Miketic, Linda M.; Tabor, Ellen K.; Yousem, Samuel A.; King, Jill L.; Gennari, Rose C.; Felice, Marc A.; Sidorovich, Kathleen
1990-08-01
In a large-scale, multi-reader study to investigate questions surrounding the issue of the implementation of picture archiving and communications systems (PACS) into the modern radiology environment, we examined the effect that the incorporation of a clinical history into the reading process would have on levels of diagnostic accuracy. Because we wanted to test the inclusion of the clinical history in an environment as close to that of the clinical situation as possible, we defined "history" to be a concise, objective, and potentially computer-extractable version of what appears in the patient records, including a statement from the referring physician when this is available. In a series of studies, four radiologists interpreted 247 posteroanterior normal and abnormal chest images on conventional film both with and without accompanying patient histories; five radiologists read the same number of images presented on a high-resolution video workstation with and without clinical histories. There were no significant differences (p = .05) in diagnostic accuracy rates with or without clinical history for either the film or the workstation in cases of interstitial disease, nodules, or pneumothorax. Diagnostic accuracy for the radiologists as a group was not affected by the presence of the clinical history. We concluded that for the interpretation of these abnormalities, the incorporation of clinical history with images in the PACS environment should not be a major goal.
-
Tsalik, Ephraim L; Petzold, Elizabeth; Kreiswirth, Barry N; Bonomo, Robert A; Banerjee, Ritu; Lautenbach, Ebbing; Evans, Scott R; Hanson, Kimberly E; Klausner, Jeffrey D; Patel, Robin
2017-03-15
Diagnostics are a cornerstone of the practice of infectious diseases. However, various limitations frequently lead to unmet clinical needs. In most other domains, diagnostics focus on narrowly defined questions, provide readily interpretable answers, and use true gold standards for development. In contrast, infectious diseases diagnostics must contend with scores of potential pathogens, dozens of clinical syndromes, emerging pathogens, rapid evolution of existing pathogens and their associated resistance mechanisms, and the absence of gold standards in many situations. In spite of these challenges, the importance and value of diagnostics cannot be underestimated. Therefore, the Antibacterial Resistance Leadership Group has identified diagnostics as 1 of 4 major areas of emphasis. Herein, we provide an overview of that development, highlighting several examples where innovation in study design, content, and execution is advancing the field of infectious diseases diagnostics. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
-
Psooy, B J; Clark, T W; Beecroft, J R; Malatjalian, D
2001-01-01
Obtaining transjugular liver biopsy specimens with use of single-use needle systems is expensive, whereas biopsy specimens obtained with use of reusable needle systems are frequently associated with inadequate core specimens. The authors report their experience with the reusable Cook Shark Jaw biopsy needle, including diagnostic yield, complications, and cost-effectiveness. A retrospective audit was performed of a cohort of 134 patients who underwent 136 transjugular liver biopsies with use of a reusable 16-gauge Shark Jaw needle during a 30-month period. Specimen adequacy and complication rates were assessed and direct costs of expendable components calculated. Cost-effectiveness was expressed as cost-per-successful biopsy. Biopsies were technically successful in 126 of 136 (93%) patients, with diagnostic histologic core specimens obtained in 124 of 126 (98%) patients, for an overall success rate of 91%. Complications included capsular penetration in six (4.4%) patients, cardiac arrhythmia in two (1.5%) patients, and puncture site hematoma or bleeding in 10 (7.4%) patients. Three tract embolizations were performed for capsular penetration. No instances of subcapsular hematoma, hemoperitoneum, or sepsis occurred, and no deaths were attributed to the procedure. The cost of expendable components totaled $103 per biopsy, corresponding to a cost-effectiveness of $113/successful biopsy. Transjugular liver biopsy specimens obtained with use of the Shark Jaw needle have a diagnostic yield comparable to those obtained with use of single-use biopsy systems, at a substantially lower cost with no increase in serious complications.
-
Nyman, R S; Cappelen-Smith, J; al Suhaibani, H; Alfurayh, O; Shakweer, W; Akhtar, M
1997-05-01
To compare the yield and complications of ultrasound-guided gun-biopsy and manual Tru-Cut techniques in percutaneous renal biopsy. A total of 448 biopsies were reviewed. They comprised 124 manual and 131 gun-biopsies in native kidneys, and 111 manual and 82 gun-biopsies in transplant kidneys. The gun-biopsies were performed under real-time ultrasound (US) guidance. The manual technique used US mainly for marking the position of the kidney. There was a significantly higher diagnostic yield and fewer complications in the gun-biopsy group. A total of 8 major complications were found, all in the manual group. Provided that the operator is experienced in US scanning, a switch from the manual technique to real-time US-guided gun-biopsy will result in the improvement of diagnostic accuracy together with a reduced risk of complications.
-
Diagnostic performance of dark-blood T2-weighted CMR for evaluation of acute myocardial injury.
Srichai, Monvadi B; Lim, Ruth P; Lath, Narayan; Babb, James; Axel, Leon; Kim, Daniel
2013-01-01
We compared the image quality and diagnostic performance of 2 fat-suppression methods for black-blood T2-weighted fast spin-echo (FSE), which are as follows: (a) short T1 inversion recovery (STIR; FSE-STIR) and (b) spectral adiabatic inversion recovery (SPAIR; FSE-SPAIR), for detection of acute myocardial injury. Edema-sensitive T2-weighted FSE cardiac magnetic resonance (CMR) imaging is useful in detecting acute myocardial injury but may experience reduced myocardial signal and signal dropout. The SPAIR pulse aims to eliminate artifacts associated with the STIR pulse. A total of 65 consecutive patients referred for CMR evaluation of myocardial structure and function underwent FSE-STIR and FSE-SPAIR, in addition to cine and late gadolinium enhancement (LGE) CMR. T2-weighted FSE images were independently evaluated by 2 readers for image quality and artifacts (Likert scale of 1-5; best-worst) and presence of increased myocardial signal suggestive of edema. In addition, clinical CMR interpretation, incorporating all CMR sequences available, was recorded for comparison. Diagnostic performance of each T2-weighted sequence was measured using recent (<30 days) troponin elevation greater than 2 times the upper limit of normal as the reference standard for acute myocardial injury. Of the 65 patients, there were 21 (32%) with acute myocardial injury. Image quality and artifact scores were significantly better with FSE-SPAIR compared with FSE-STIR (2.15 vs 2.68, P < 0.01; 2.62 vs 3.05, P < 0.01, respectively). The sensitivity, specificity, positive predictive value, and negative predictive value for acute myocardial injury were as follows: 29%, 93%, 67%, and 73% for FSE-SPAIR; 38%, 91%, 67%, and 75% for FSE-STIR; 71%, 98%, 94%, and 88% for clinical interpretation including LGE, T2, and wall motion. There was a statistically significant difference in sensitivity between the clinical interpretation and each of the T2-weighted sequences but not between each T2-weighted sequence. Although FSE-SPAIR demonstrated significantly improved image quality and decreased artifacts, isolated interpretations of each T2-weighted technique demonstrated high specificity but overall low sensitivity for the detection of myocardial injury, with no difference in accuracy between the techniques. However, real-world interpretation in combination with cine and LGE CMR methods significantly improves the overall sensitivity and diagnostic performance.
-
Elmore, Joann G.; Nelson, Heidi D.; Pepe, Margaret S.; Longton, Gary M.; Tosteson, Anna N.A.; Geller, Berta; Onega, Tracy; Carney, Patricia A.; Jackson, Sara L.; Allison, Kimberly H.; Weaver, Donald L.
2016-01-01
Background The effect of physician diagnostic variability on accuracy at a population level depends on the prevalence of diagnoses. Objective To estimate how diagnostic variability affects accuracy from the perspective of a U.S. woman aged 50 to 59 years having a breast biopsy. Design Applied probability using Bayes theorem. Setting B-Path (Breast Pathology) Study comparing pathologists’ interpretations of a single biopsy slide versus a reference consensus interpretation from 3 experts. Participants 115 practicing pathologists (6900 total interpretations from 240 distinct cases). Measurements A single representative slide from each of the 240 cases was used to estimate the proportion of biopsies with a diagnosis that would be verified if the same slide were interpreted by a reference group of 3 expert pathologists. Probabilities of confirmation (predictive values) were estimated using B-Path Study results and prevalence of biopsy diagnoses for women aged 50 to 59 years in the Breast Cancer Surveillance Consortium. Results Overall, if 1 representative slide were used per case, 92.3% (95% CI, 91.4% to 93.1%) of breast biopsy diagnoses would be verified by reference consensus diagnoses, with 4.6% (CI, 3.9% to 5.3%) overinterpreted and 3.2% (CI, 2.7% to 3.6%) underinterpreted. Verification of invasive breast cancer and benign without atypia diagnoses is highly probable; estimated predictive values were 97.7% (CI, 96.5% to 98.7%) and 97.1% (CI, 96.7% to 97.4%), respectively. Verification is less probable for atypia (53.6% overinterpreted and 8.6% underinterpreted) and ductal carcinoma in situ (DCIS) (18.5% overinterpreted and 11.8% underinterpreted). Limitations Estimates are based on a testing situation with 1 slide used per case and without access to second opinions. Population-adjusted estimates may differ for women from other age groups, unscreened women, or women in different practice settings. Conclusion This analysis, based on interpretation of a single breast biopsy slide per case, predicts a low likelihood that a diagnosis of atypia or DCIS would be verified by a reference consensus diagnosis. This diagnostic gray zone should be considered in clinical management decisions in patients with these diagnoses. Primary Funding Source National Cancer Institute. PMID:26999810
-
Allison, Kimberly H; Rendi, Mara H; Peacock, Sue; Morgan, Tom; Elmore, Joann G; Weaver, Donald L
2016-12-01
This study examined the case-specific characteristics associated with interobserver diagnostic agreement in atypical ductal hyperplasia (ADH) of the breast. Seventy-two test set cases with a consensus diagnosis of ADH from the B-Path study were evaluated. Cases were scored for 17 histological features, which were then correlated with the participant agreement with the consensus ADH diagnosis. Participating pathologists' perceptions of case difficulty, borderline features or whether they would obtain a second opinion were also examined for associations with agreement. Of the 2070 participant interpretations of the 72 consensus ADH cases, 48% were scored by participants as difficult and 45% as borderline between two diagnoses; the presence of both of these features was significantly associated with increased agreement (P < 0.001). A second opinion would have been obtained in 80% of interpretations, and this was associated with increased agreement (P < 0.001). Diagnostic agreement ranged from 10% to 89% on a case-by-case basis. Cases with papillary lesions, cribriform architecture and obvious cytological monotony were associated with higher agreement. Lower agreement rates were associated with solid or micropapillary architecture, borderline cytological monotony, or cases without a diagnostic area that was obvious on low power. The results of this study suggest that pathologists frequently recognize the challenge of ADH cases, with some cases being more prone to diagnostic variability. In addition, there are specific histological features associated with diagnostic agreement on ADH cases. Multiple example images from cases in this test set are provided to serve as educational illustrations of these challenges. © 2016 John Wiley & Sons Ltd.
-
Allison, Kimberly H.; Rendi, Mara H.; Peacock, Sue; Morgan, Tom; Elmore, Joann G.; Weaver, Donald L.
2016-01-01
Background Case specific characteristics associated with interobserver diagnostic agreement in atypical ductal hyperplasia (ADH) of the breast are poorly understood. Methods Seventy-two test set cases with a consensus diagnosis of ADH from the B-Path study were evaluated. Cases were scored for 17 histologic features which were then correlated with the participant agreement with the consensus ADH diagnosis. Participating pathologists’ perceptions of case difficulty, borderline features, or if they would obtain a second opinion were also examined for associations with agreement. Results Of the 2,070 participant interpretations on the 72 consensus ADH cases, 48% were scored by participants as difficult and 45% as borderline between two diagnoses; the presence of both of these features was significantly associated with increased agreement (p < 0.001). A second opinion would have been obtained in 80% of interpretations, and this was associated with increased agreement (p < 0.001). Diagnostic agreement ranged from 10–89% on a case-by-case basis. Cases with papillary lesions, cribriform architecture and obvious cytologic monotony were associated with higher agreement. Lower agreement rates were associated with solid or micro-papillary architecture, borderline cytologic monotony or cases without a diagnostic area that was obvious on low power. Conclusions The results of this study suggest that pathologists frequently recognize the challenge of ADH cases with some cases more prone to diagnostic variability. In addition, there are specific histologic features associated with diagnostic agreement on ADH cases. Multiple example images from cases in this test set are provided to serve as educational illustrations of these challenges. PMID:27398812
-
Vacuum system design and tritium inventory for the TFTR charge exchange diagnostic
DOE Office of Scientific and Technical Information (OSTI.GOV)
Medley, S.S.
The charge exchange diagnostic for the TFTR is comprised of two analyzer systems which contain a total of twenty independent mass/energy analyzers and one diagnostic neutral beam tentatively rated at 80 keV, 15 A. The associated vacuum systems were analyzed using the Vacuum System Transient Simulator (VSTS) computer program which models the transient transport of multi-gas species through complex networks of ducts, valves, traps, vacuum pumps, and other related vacuum system components. In addition to providing improved design performance at reduced cost, the analysis yields estimates for the exchange of tritium from the torus to the diagnostic components and ofmore » the diagnostic working gases to the torus.« less
-
Izumida, Toshihide; Sakata, Hidenao; Nakamura, Masahiko; Hayashibara, Yumiko; Inasaki, Noriko; Inahata, Ryo; Hasegawa, Sumiyo; Takizawa, Takenori; Kaya, Hiroyasu
2016-01-01
An outbreak of dengue fever occurred in Japan in August 2014. We herein report the case of a 63-year-old man who presented with a persistent fever in September 2014. Acute parvovirus B19 infection led to a false positive finding of dengue fever on a rapid diagnostic test (Panbio Dengue Duo Cassette(TM)). To the best of our knowledge, there are no previous reports of a false positive result for dengue IgM with the dengue rapid diagnostic test. We believe that epidemiological information on the prevalence of parvovirus B19 is useful for guiding the interpretation of a positive result with the dengue rapid diagnostic test.
-
Henderson, Louise M.; Benefield, Thad; Bowling, J. Michael; Durham, Danielle; Marsh, Mary W.; Schroeder, Bruce F.; Yankaskas, Bonnie C.
2015-01-01
Objective The purpose of this study was to determine whether the technologist has an effect on the radiologists’ interpretative performance of diagnostic mammography. Materials and Methods Using data from a community based mammography registry from 1994 to 2009, we identified 162,755 diagnostic mammograms interpreted by 286 radiologists and performed by 303 mammographic technologists. We calculated sensitivity, false positive rate, and positive predictive value of biopsy (PPV2) for examinations performed (images taken) by each mammographic technologist, separately for film and digital modalities. We assessed the variability of these performance measures among mammographic technologists, using mixed effects logistic regression and taking into account the clustering of examinations within women, radiologists, and radiology practice. Results Among the 291 technologists performing film examinations, mean sensitivity of the examinations they performed was 83.0% (95% Confidence Interval (CI)=80.8–85.2%), mean false positive rate was 8.5 per 1000 examinations (95%CI: 8.0–9.0%), and mean PPV2 was 27.1% (95%CI: 24.8–29.4). For the 45 technologists performing digital examinations, mean sensitivity of the examinations they performed was 79.6% (95%CI: 73.1–86.2%), mean false positive rate was 8.8 (95%CI: 7.5–10.0%), and mean PPV2 was 23.6% (95%CI: 18.8–28.4%). We found significant variation by technologist in the sensitivity, false positive rate, and PPV2 for film but not digital mammography (p<0.0001 for all 3 film performance measures). Conclusions Our results suggest that the technologist has an influence on radiologists’ performance of diagnostic film mammography but not digital. Future work should examine why this difference by modality exists and determine if similar patterns are observed for screening mammography. PMID:25794085
-
Diagnostic Yield of 2 Strategies for Adult Celiac Disease Identification in Primary Care.
Scoglio, Riccardo; Trifirò, Gianluca; Sandullo, Antonino; Marangio, Giovanni; D'Agate, Cinzia; Costa, Stefano; Pellegrino, Salvatore; Alibrandi, Angela; Aiello, Andrea; Currò, Giovanni; Cuzzupè, Chiara; Comisi, Fabrizio; Amato, Salvatore; Conti Nibali, Roberto; Oteri, Sergio; Magazzu, Giuseppe; Carroccio, Antonio
2017-12-18
To compare the diagnostic yield and cost-consequences of 2 strategies, screening regardless of symptoms versus case finding (CF), using a point-of-care test (POCT), for the detection of celiac disease (CD) in primary care, to bridge the diagnostic gap of CD in adults. All subjects under 75 years of age who consecutively went to their general practitioners' offices were offered POCT for anti-transglutaminase immunoglobulin A antibodies. The POCT was performed on all subjects who agreed, and then a systematic search for symptoms or conditions associated with higher risk for CD was performed, immediately after the test but before knowing the test results. The 2 resulting groups were: (a) POCT positive and (b) symptomatic subject at CF. Subjects were defined as symptomatic at CF in the presence of 1 or more symptoms. All POCT-positive or symptomatic subjects at CF were referred to the CD Centers for confirmation of CD. Data on resource consumption were gathered from patients' charts. Cost of examinations, and diagnostic and laboratory tests were estimated with regional outpatient tariffs (Sicily), and a price of &OV0556;2.5 was used for each POCT. Of a total of 2197 subjects who agreed to participate in the study, 36 (1.6%) and 671 (30.5%) were POCT positive and symptomatic at CF, respectively. The yield from the screening and CF was 5 new celiac patients. The total cost and mean cost for each new CD case were &OV0556;7497.35 and &OV0556;1499.47 for the POCT screening strategy, and &OV0556;9855.14 and &OV0556;1971.03 for the CF strategy, respectively. Assuming consecutive use of both strategies, performing POCT only in symptomatic subjects at CF, the calculated yield would be 4 new diagnoses with a total cost of &OV0556;2345.84 and a mean cost of &OV0556;586.46 for each newly diagnosed patient. Only 1 patient was celiac despite a negative POCT. Testing symptomatic subjects at CF only by POCT seems the most cost-effective strategy to bridge the diagnostic gap of adult CD in primary care.
-
Dennis, Eslie; Banks, Peter; Murata, Lauren B; Sanchez, Stephanie A; Pennington, Christie; Hockersmith, Linda; Miller, Rachel; Lambe, Jess; Feng, Janine; Kapadia, Monesh; Clements, June; Loftin, Isabell; Singh, Shalini; Das-Gupta, Ashis; Lloyd, William; Bloom, Kenneth
2016-10-01
Companion diagnostics assay interpretation can select patients with the greatest targeted therapy benefits. We present the results from a prospective study demonstrating that pathologists can effectively learn immunohistochemical assay-interpretation skills from digital image-based electronic training (e-training). In this study, e-training was used to train board-certified pathologists to evaluate non-small cell lung carcinoma for eligibility for treatment with onartuzumab, a MET-inhibiting agent. The training program mimicked the live training that was previously validated in clinical trials for onartuzumab. A digital interface was developed for pathologists to review high-resolution, static images of stained slides. Sixty-four pathologists practicing in the United States enrolled while blinded to the type of training. After training, both groups completed a mandatory final test using glass slides. The results indicated both training modalities to be effective. Overall, 80.6% of e-trainees and 72.7% of live trainees achieved passing scores (at least 85%) on the final test. All study participants reported that their training experience was "good" and that they had received sufficient information to determine the adequacy of case slide staining to score each case. This study established that an e-training program conducted under highly controlled conditions can provide pathologists with the skills necessary to interpret a complex assay and that these skills can be equivalent to those achieved with face-to-face training using conventional microscopy. Programs of this type are scalable for global distribution and offer pathologists the potential for readily accessible and robust training in new companion diagnostic assays linked to novel, targeted, adjuvant therapies for cancer patients. Copyright © 2016 Elsevier Inc. All rights reserved.
-
Application and Utility of iPads in Pediatric Tele-echocardiography.
Colombo, Jamie N; Seckeler, Michael D; Barber, Brent J; Krupinski, Elizabeth A; Weinstein, Ronald S; Sisk, David; Lax, Daniela
2016-05-01
Telemedicine is used with increasing frequency to improve patient care in remote areas. The interpretation of medical imaging on iPad(®) (Apple, Cupertino, CA) tablets has been reported to be accurate. There are no studies on the use of iPads for interpretation of pediatric echocardiograms. We compared the quality of echo images, diagnostic accuracy, and review time using three different modalities: remote access on an iPad Air (iPad), remote access via a computer (Remote), and direct access on a computer linked through Ethernet to the server, the "gold standard" (Direct). Fifty consecutive archived pediatric echocardiograms were interpreted using the three modalities. Studies were analyzed blindly by three pediatric cardiologists; review time, diagnostic accuracy, and image quality were documented. Diagnostic accuracy was assessed by comparing the study diagnoses with the official diagnosis in the patient's chart. Discrepancies between diagnoses were graded as major (more than one grade difference) or minor (one grade difference in severity of lesion). There were no significant differences in accuracy among the three modalities. There was one major discrepancy (size of patent ductus arteriosus); all others were minor, hemodynamically insignificant. Image quality ratings were better for iPad than Remote; Direct had the highest ratings. Review times (mean [standard deviation] minutes) were longest for iPad (5.89 [3.87]) and then Remote (4.72 [2.69]), with Direct having the shortest times (3.52 [1.42]) (p < 0.0001). Pediatric echocardiograms can be interpreted using convenient, portable devices while preserving accuracy and quality with slightly longer review times (1-2 min). These findings are important in the current era of increasing need for mobile health.
-
Interpreting IgE sensitization tests in food allergy.
Chokshi, Niti Y; Sicherer, Scott H
2016-01-01
Food allergies are increasing in prevalence, and with it, IgE testing to foods is becoming more commonplace. Food-specific IgE tests, including serum assays and prick skin tests, are sensitive for detecting the presence of food-specific IgE (sensitization), but specificity for predicting clinical allergy is limited. Therefore, positive tests are generally not, in isolation, diagnostic of clinical disease. However, rationale test selection and interpretation, based on clinical history and understanding of food allergy epidemiology and pathophysiology, makes these tests invaluable. Additionally, there exist highly predictive test cutoff values for common allergens in atopic children. Newer testing methodologies, such as component resolved diagnostics, are promising for increasing the utility of testing. This review highlights the use of IgE serum tests in the diagnosis of food allergy.
-
NASA Astrophysics Data System (ADS)
Wormanns, Dag; Klotz, Ernst; Dregger, Uwe; Beyer, Florian; Heindel, Walter
2004-05-01
Lack of angiogenesis virtually excludes malignancy of a pulmonary nodule; assessment with quantitative contrast-enhanced CT (QECT) requires a reliable enhancement measurement technique. Diagnostic performance of different measurement methods in the distinction between malignant and benign nodules was evaluated. QECT (unenhanced scan and 4 post-contrast scans) was performed in 48 pulmonary nodules (12 malignant, 12 benign, 24 indeterminate). Nodule enhancement was the difference between the highest nodule density at any post-contrast scan and the unenhanced scan. Enhancement was determined with: A) the standard 2D method; B) a 3D method consisting of segmentation, removal of peripheral structures and density averaging. Enhancement curves were evaluated for their plausibility using a predefined set of criteria. Sensitivity and specificity were 100% and 33% for the 2D method resp. 92% and 55% for the 3D method using a threshold of 20 HU. One malignant nodule did not show significant enhancement with method B due to adjacent atelectasis which disappeared within the few minutes of the QECT examination. Better discrimination between benign and malignant lesions was achieved with a slightly higher threshold than proposed in the literature. Application of plausibility criteria to the enhancement curves rendered less plausibility faults with the 3D method. A new 3D method for analysis of QECT scans yielded less artefacts and better specificity in the discrimination between benign and malignant pulmonary nodules when using an appropriate enhancement threshold. Nevertheless, QECT results must be interpreted with care.
-
30 CFR 250.522 - When do I have to repeat casing diagnostic testing?
Code of Federal Regulations, 2010 CFR
2010-07-01
..., previously on gas lift, has been shut-in or returned to flowing status without gas lift for more than 180... active gas lift are exempt from diagnostic testing. (c) your casing pressure request becomes invalid... percent of its minimum internal yield pressure (MIYP), except for production casings on active gas lift...
-
Introduction to basic solar cell measurements
NASA Technical Reports Server (NTRS)
Brandhorst, H. W., Jr.
1976-01-01
The basic approaches to solar cell performance and diagnostic measurements are described. The light sources, equipment for I-V curve measurement, and the test conditions and procedures for performance measurement are detailed. Solar cell diagnostic tools discussed include analysis of I-V curves, series resistance and reverse saturation current determination, spectral response/quantum yield measurement, and diffusion length/lifetime determination.
-
Code of Federal Regulations, 2010 CFR
2010-10-01
... section 1833(h)(5)(A) of the Act), if a physician or other supplier bills for the technical component (TC... behalf of the beneficiary) for the TC or PC of the diagnostic test may not exceed the lowest of the... purposes of this paragraph (a)(1) only, with respect to the TC, the performing supplier is the physician...
-
Giordano, P C
2013-10-01
The consistent multi-ethnic migrations of the last decades have considerably changed the epidemiology of the hemoglobinopathies. Healthy carriers of these conditions are present today in many nonendemic parts of the world, and severely affected children are now born where these diseases were previously rare or unknown. Improving the competence in carrier diagnostics at the laboratory level is one of the first concerns when introducing management and primary prevention of the severe conditions in nonendemic areas. This review describes how and when carriers should be correctly diagnosed and informed. The essential technologies needed for basic carrier diagnostics in different situations are summarized in some detail, and interpretation of the results and a number of related problems are discussed. The role of the hematology laboratory is essential, particularly in nonendemic areas where the first line of health care is often insufficiently aware of hemoglobinopathy management. Carriers living in nonendemic areas can be appropriately diagnosed and informed regarding genetic risk and prevention by well-organized laboratories. Both basic and specialized diagnostics are needed for the correct treatment for the anemic carriers, for primary prevention in couples at risk and for state-of-the art care of severely affected patients. © 2012 John Wiley & Sons Ltd.
-
NASA Astrophysics Data System (ADS)
Elze, Tobias; Baniasadi, Neda; Jin, Qingying; Wang, Hui; Wang, Mengyu
2017-12-01
Retinal nerve fiber layer thickness (RNFLT) measured by optical coherence tomography (OCT) is widely used in clinical practice to support glaucoma diagnosis. Clinicians frequently interpret peripapillary RNFLT areas marked as abnormal by OCT machines. However, presently, clinical OCT machines do not take individual retinal anatomy variation into account, and according diagnostic biases have been shown particularly for patients with ametropia. The angle between the two major temporal retinal arteries (interartery angle, IAA) is considered a fundamental retinal ametropia marker. Here, we analyze peripapillary spectral domain OCT RNFLT scans of 691 glaucoma patients and apply multivariate logistic regression to quantitatively compare the diagnostic bias of spherical equivalent (SE) of refractive error and IAA and to identify the precise retinal locations of false-positive/negative abnormality marks. Independent of glaucoma severity (visual field mean deviation), IAA/SE variations biased abnormality marks on OCT RNFLT printouts at 36.7%/22.9% of the peripapillary area, respectively. 17.2% of the biases due to SE are not explained by IAA variation, particularly in inferonasal areas. To conclude, the inclusion of SE and IAA in OCT RNFLT norms would help to increase diagnostic accuracy. Our detailed location maps may help clinicians to reduce diagnostic bias while interpreting retinal OCT scans.
-
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, Lei
Magnetic confinement fusion is one of the most promising approaches to achieve fusion energy. With the rapid increase of the computational power over the past decades, numerical simulation have become an important tool to study the fusion plasmas. Eventually, the numerical models will be used to predict the performance of future devices, such as the International Thermonuclear Experiment Reactor (ITER) or DEMO. However, the reliability of these models needs to be carefully validated against experiments before the results can be trusted. The validation between simulations and measurements is hard particularly because the quantities directly available from both sides are different.more » While the simulations have the information of the plasma quantities calculated explicitly, the measurements are usually in forms of diagnostic signals. The traditional way of making the comparison relies on the diagnosticians to interpret the measured signals as plasma quantities. The interpretation is in general very complicated and sometimes not even unique. In contrast, given the plasma quantities from the plasma simulations, we can unambiguously calculate the generation and propagation of the diagnostic signals. These calculations are called synthetic diagnostics, and they enable an alternate way to compare the simulation results with the measurements. In this dissertation, we present a platform for developing and applying synthetic diagnostic codes. Three diagnostics on the platform are introduced. The reflectometry and beam emission spectroscopy diagnostics measure the electron density, and the electron cyclotron emission diagnostic measures the electron temperature. The theoretical derivation and numerical implementation of a new two dimensional Electron cyclotron Emission Imaging code is discussed in detail. This new code has shown the potential to address many challenging aspects of the present ECE measurements, such as runaway electron effects, and detection of the cross phase between the electron temperature and density fluctuations.« less
-
Binnicker, M. J.; Jespersen, D. J.; Harring, J. A.; Rollins, L. O.; Bryant, S. C.; Beito, E. M.
2008-01-01
The diagnosis of Lyme borreliosis (LB) is commonly made by serologic testing with Western blot (WB) analysis serving as an important supplemental assay. Although specific, the interpretation of WBs for diagnosis of LB (i.e., Lyme WBs) is subjective, with considerable variability in results. In addition, the processing, reading, and interpretation of Lyme WBs are laborious and time-consuming procedures. With the need for rapid processing and more objective interpretation of Lyme WBs, we evaluated the performances of two automated interpretive systems, TrinBlot/BLOTrix (Trinity Biotech, Carlsbad, CA) and BeeBlot/ViraScan (Viramed Biotech AG, Munich, Germany), using 518 serum specimens submitted to our laboratory for Lyme WB analysis. The results of routine testing with visual interpretation were compared to those obtained by BLOTrix analysis of MarBlot immunoglobulin M (IgM) and IgG and by ViraScan analysis of ViraBlot and ViraStripe IgM and IgG assays. BLOTrix analysis demonstrated an agreement of 84.7% for IgM and 87.3% for IgG compared to visual reading and interpretation. ViraScan analysis of the ViraBlot assays demonstrated agreements of 85.7% for IgM and 94.2% for IgG, while ViraScan analysis of the ViraStripe IgM and IgG assays showed agreements of 87.1 and 93.1%, respectively. Testing by the automated systems yielded an average time savings of 64 min/run compared to processing, reading, and interpretation by our current procedure. Our findings demonstrated that automated processing and interpretive systems yield results comparable to those of visual interpretation, while reducing the subjectivity and time required for Lyme WB analysis. PMID:18463211
-
Binnicker, M J; Jespersen, D J; Harring, J A; Rollins, L O; Bryant, S C; Beito, E M
2008-07-01
The diagnosis of Lyme borreliosis (LB) is commonly made by serologic testing with Western blot (WB) analysis serving as an important supplemental assay. Although specific, the interpretation of WBs for diagnosis of LB (i.e., Lyme WBs) is subjective, with considerable variability in results. In addition, the processing, reading, and interpretation of Lyme WBs are laborious and time-consuming procedures. With the need for rapid processing and more objective interpretation of Lyme WBs, we evaluated the performances of two automated interpretive systems, TrinBlot/BLOTrix (Trinity Biotech, Carlsbad, CA) and BeeBlot/ViraScan (Viramed Biotech AG, Munich, Germany), using 518 serum specimens submitted to our laboratory for Lyme WB analysis. The results of routine testing with visual interpretation were compared to those obtained by BLOTrix analysis of MarBlot immunoglobulin M (IgM) and IgG and by ViraScan analysis of ViraBlot and ViraStripe IgM and IgG assays. BLOTrix analysis demonstrated an agreement of 84.7% for IgM and 87.3% for IgG compared to visual reading and interpretation. ViraScan analysis of the ViraBlot assays demonstrated agreements of 85.7% for IgM and 94.2% for IgG, while ViraScan analysis of the ViraStripe IgM and IgG assays showed agreements of 87.1 and 93.1%, respectively. Testing by the automated systems yielded an average time savings of 64 min/run compared to processing, reading, and interpretation by our current procedure. Our findings demonstrated that automated processing and interpretive systems yield results comparable to those of visual interpretation, while reducing the subjectivity and time required for Lyme WB analysis.
-
NASA Astrophysics Data System (ADS)
Chen, Po-Hao; Botzolakis, Emmanuel; Mohan, Suyash; Bryan, R. N.; Cook, Tessa
2016-03-01
In radiology, diagnostic errors occur either through the failure of detection or incorrect interpretation. Errors are estimated to occur in 30-35% of all exams and contribute to 40-54% of medical malpractice litigations. In this work, we focus on reducing incorrect interpretation of known imaging features. Existing literature categorizes cognitive bias leading a radiologist to an incorrect diagnosis despite having correctly recognized the abnormal imaging features: anchoring bias, framing effect, availability bias, and premature closure. Computational methods make a unique contribution, as they do not exhibit the same cognitive biases as a human. Bayesian networks formalize the diagnostic process. They modify pre-test diagnostic probabilities using clinical and imaging features, arriving at a post-test probability for each possible diagnosis. To translate Bayesian networks to clinical practice, we implemented an entirely web-based open-source software tool. In this tool, the radiologist first selects a network of choice (e.g. basal ganglia). Then, large, clearly labeled buttons displaying salient imaging features are displayed on the screen serving both as a checklist and for input. As the radiologist inputs the value of an extracted imaging feature, the conditional probabilities of each possible diagnosis are updated. The software presents its level of diagnostic discrimination using a Pareto distribution chart, updated with each additional imaging feature. Active collaboration with the clinical radiologist is a feasible approach to software design and leads to design decisions closely coupling the complex mathematics of conditional probability in Bayesian networks with practice.
-
Kwon, David; Bouffard, J Antonio; van Holsbeeck, Marnix; Sargsyan, Asot E; Hamilton, Douglas R; Melton, Shannon L; Dulchavsky, Scott A
2007-03-01
National Aeronautical and Space and Administration (NASA) researchers have optimized training methods that allow minimally trained, non-physician operators to obtain diagnostic ultrasound (US) images for medical diagnosis including musculoskeletal injury. We hypothesize that these techniques could be expanded to non-expert operators including National Hockey League (NHL) and Olympic athletic trainers to diagnose musculoskeletal injuries in athletes. NHL and Olympic athletic trainers received a brief course on musculoskeletal US. Remote guidance musculoskeletal examinations were conducted by athletic trainers, consisting of hockey groin hernia, knee, ankle, elbow, or shoulder evaluations. US images were transmitted to remote experts for interpretation. Groin, knee, ankle, elbow, or shoulder images were obtained on 32 athletes; all real-time US video stream and still capture images were considered adequate for diagnostic interpretation. This experience suggests that US can be expanded for use in locations without a high level of on-site expertise. A non-physician with minimal training can perform complex, diagnostic-quality examinations when directed by a remote-based expert.
-
Venkatesh, Santosh S; Levenback, Benjamin J; Sultan, Laith R; Bouzghar, Ghizlane; Sehgal, Chandra M
2015-12-01
The goal of this study was to devise a machine learning methodology as a viable low-cost alternative to a second reader to help augment physicians' interpretations of breast ultrasound images in differentiating benign and malignant masses. Two independent feature sets consisting of visual features based on a radiologist's interpretation of images and computer-extracted features when used as first and second readers and combined by adaptive boosting (AdaBoost) and a pruning classifier resulted in a very high level of diagnostic performance (area under the receiver operating characteristic curve = 0.98) at a cost of pruning a fraction (20%) of the cases for further evaluation by independent methods. AdaBoost also improved the diagnostic performance of the individual human observers and increased the agreement between their analyses. Pairing AdaBoost with selective pruning is a principled methodology for achieving high diagnostic performance without the added cost of an additional reader for differentiating solid breast masses by ultrasound. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
-
Use of diagnostics in wound management.
Romanelli, Marco; Miteva, Maria; Romanelli, Paolo; Barbanera, Sabrina; Dini, Valentina
2013-03-01
Wound healing research has progressed impressively over the past years. New insights into the pathogenesis of different chronic wounds and the study of novel treatment have made wound healing a model disorder and have revealed basic cellular and molecular mechanisms underlying chronic wounds. Although the observation is so obvious and simple, the interpretations by different observers can be quite variable. The interpretations of severity and change in severity by treatment may differ considerably between patient and practitioners. In this review we provide comprehensive view on different aspects of wound diagnostic, including clinical measurement, new biomarkers in wound pathology, proteases evaluation, and future noninvasive sensor-based devices. Wound caregivers are in the unique position of being able to observe the wound changes and describe these with knowledge and strict methodology, but also with the wide range of available wound diagnostic devices. The complexity of severity assessment in wound healing is reflected by the multiple clinical scores available. The best objective methods used to evaluate cutaneous tissue repair should have a high specificity and sensitivity and a low inter and intraobserver variation.
-
Renal angina: concept and development of pretest probability assessment in acute kidney injury.
Chawla, Lakhmir S; Goldstein, Stuart L; Kellum, John A; Ronco, Claudio
2015-02-27
The context of a diagnostic test is a critical component for the interpretation of its result. This context defines the pretest probability of the diagnosis and forms the basis for the interpretation and value of adding the diagnostic test. In the field of acute kidney injury, a multitude of early diagnostic biomarkers have been developed, but utilization in the appropriate context is less well understood and has not been codified until recently. In order to better operationalize the context and pretest probability assessment for acute kidney injury diagnosis, the renal angina concept was proposed in 2010 for use in both children and adults. Renal angina has been assessed in approximately 1,000 subjects. However, renal angina as a concept is still unfamiliar to most clinicians and the rationale for introducing the term is not obvious. We therefore review the concept and development of renal angina, and the currently available data validating it. We discuss the various arguments for and against this construct. Future research testing the performance of renal angina with acute kidney injury biomarkers is warranted.
-
Diagnostic yield of electromyography in children with myopathic disorders.
Ghosh, Partha S; Sorenson, Eric J
2014-08-01
Interpretation of pediatric electromyography interpretation in myopathic disorders is technically challenging. We assessed our electromyographic experience with respect to sensitivity and specificity in pediatric myopathy. We did a retrospective chart review of patients ≤18 years between 2009 and 2013. Two hundred twenty-four electromyographic studies were reviewed with the following referral diagnoses: myopathy, muscle weakness, neuromuscular disorders, myositis, myalgia, myoglobinuria, myasthenia, myotonia, cramps, periodic paralysis, hypotonia, and developmental delay. Only children who had an electromyography and muscle biopsy were included for analysis. Patients with neurogenic electromyography and neuromuscular junction disorders were excluded. Myopathic electromyography was defined as short duration, low amplitude, polyphasic motor unit potentials with rapid recruitment. Seventy-two patients were included (age range, 6 months-18 years). The following observations were made: group A: myopathic electromyography or pathognomonic of muscle disease and biopsy or genetically confirmed myopathy (32 cases); group B: myopathic electromyography but biopsy normal or nondiagnostic (12 cases); group C: normal electromyography but biopsy or genetically confirmed myopathy (three cases, all with metabolic myopathy); and group D: electromyography normal and biopsy normal or nondiagnostic (25 cases). The most common diagnoses were congenital myopathy (seven cases), metabolic myopathy (six cases), muscular dystrophy (six cases), genetically confirmed myopathy (five cases), myopathy, undefined (five cases), and inflammatory myopathy (four cases). Pediatric electromyography was 91% sensitive and 67% specific in myopathic disorders. The metabolic myopathies were commonly missed by electromyography. Copyright © 2014 Elsevier Inc. All rights reserved.
-
Berg, Wendie A.; Blume, Jeffrey D.; Cormack, Jean B.; Mendelson, Ellen B.; Lehrer, Daniel; Böhm-Vélez, Marcela; Pisano, Etta D.; Jong, Roberta A.; Evans, W. Phil; Morton, Marilyn J.; Mahoney, Mary C.; Larsen, Linda Hovanessian; Barr, Richard G.; Farria, Dione M.; Marques, Helga S.; Boparai, Karan
2008-01-01
Context Screening ultrasound (US) may depict small, node-negative breast cancers not seen on mammography (M). Objective To compare the diagnostic yield (proportion of women with a positive screen test and positive reference standard) and performance of screening with US+M compared to M alone in women at elevated risk of breast cancer. Design, Setting, and Participants From April 2004 to February 2006, 2809 women at elevated risk for breast cancer, with at least heterogeneously dense breast tissue in at least one quadrant, were recruited from 21 IRB-approved sites to undergo mammography (M) and physician-performed ultrasound (US) exams in randomized order by a radiologist masked to the results of the other exam. Reference standard was defined as a combination of pathology and 12 month follow-up, and was available for 2637 out of the 2725 eligible participants. Main Outcome Measure Diagnostic yield, sensitivity, specificity, and AUC of combined M+US compared to M alone; PPV of biopsy recommendations for M+US compared to M alone. Results Forty participants (41 breasts) were diagnosed with cancer: 8 suspicious on both US and M, 12 on US alone, 12 on M alone, and 8 participants (9 breasts) on neither (interval cancers). The diagnostic yield for M was 7.6 per 1000 women screened (20/2637) and increased to 11.8 per 1000 (31/2637) for combined US+M; the supplemental yield was 4.2 per 1000 women screened (95% CI 1.1 to 7.2 per 1000; p = 0.003 that the supplemental yield is zero). The diagnostic accuracy (AUC) for M was 0.78 (95% CI 0.67 to 0.87) and increased to 0.91 (95% CI 0.84 to 0.96) for US+M (p = 0.003 that difference is zero). Of 12 supplemental cancers seen only by US, 11 (92%) were invasive with median size 10 mm (range 5 to 40 mm; mean 12.6, SE 3.0) and 8/9 (89%) reported had negative nodes. PPV of biopsy recommendation after full diagnostic workup (PPV2) was 84/276 for M (22.6%, 95% CI 14.2 to 33%), 21/235 for US (8.9%, 95% CI 5.6 to 13.3%), and 31/276 for combined US+M (11.2%, 95% CI 7.8 to 15.6%). Conclusions Adding a single screening US to M will yield an additional 1.1 to 7.2 cancers per 1000 high-risk women, but will also substantially increase the number of false positives. Evaluation of the role of annual screening US is ongoing in this patient population. [Clinicaltrials.gov registry # NCT00072501] PMID:18477782
-
Rennie, Waverly; Phetsouvanh, Rattanaxay; Lupisan, Socorro; Vanisaveth, Viengsay; Hongvanthong, Bouasy; Phompida, Samlane; Alday, Portia; Fulache, Mila; Lumagui, Richard; Jorgensen, Pernille; Bell, David; Harvey, Steven
2007-01-01
The usefulness of rapid diagnostic tests (RDT) in malaria case management depends on the accuracy of the diagnoses they provide. Despite their apparent simplicity, previous studies indicate that RDT accuracy is highly user-dependent. As malaria RDTs will frequently be used in remote areas with little supervision or support, minimising mistakes is crucial. This paper describes the development of new instructions (job aids) to improve health worker performance, based on observations of common errors made by remote health workers and villagers in preparing and interpreting RDTs, in the Philippines and Laos. Initial preparation using the instructions provided by the manufacturer was poor, but improved significantly with the job aids (e.g. correct use both of the dipstick and cassette increased in the Philippines by 17%). However, mistakes in preparation remained commonplace, especially for dipstick RDTs, as did mistakes in interpretation of results. A short orientation on correct use and interpretation further improved accuracy, from 70% to 80%. The results indicate that apparently simple diagnostic tests can be poorly performed and interpreted, but provision of clear, simple instructions can reduce these errors. Preparation of appropriate instructions and training as well as monitoring of user behaviour are an essential part of rapid test implementation.
-
Lee, Edward Y; Jenkins, Kathy J; Muneeb, Muhammad; Marshall, Audrey C; Tracy, Donald A; Zurakowski, David; Boiselle, Phillip M
2013-08-01
One of the important benefits of using multidetector computed tomography (MDCT) is its capability to generate high-quality two-dimensional (2-D) multiplanar (MPR) and three-dimensional (3-D) images from volumetric and isotropic axial CT data. However, to the best of our knowledge, no results have been published on the potential diagnostic role of multiplanar and 3-D volume-rendered (VR) images in detecting pulmonary vein stenosis, a condition in which MDCT has recently assumed a role as the initial noninvasive imaging modality of choice. The purpose of this study was to compare diagnostic accuracy and interpretation time of axial, multiplanar and 3-D VR images for detection of proximal pulmonary vein stenosis in children, and to assess the potential added diagnostic value of multiplanar and 3-D VR images. We used our hospital information system to identify all consecutive children (< 18 years of age) with proximal pulmonary vein stenosis who had both a thoracic MDCT angiography study and a catheter-based conventional angiography within 2 months from June 2005 to February 2012. Two experienced pediatric radiologists independently reviewed each MDCT study for the presence of proximal pulmonary vein stenosis defined as ≥ 50% of luminal narrowing on axial, multiplanar and 3-D VR images. Final diagnosis was confirmed by angiographic findings. Diagnostic accuracy was compared using the z-test. Confidence level of diagnosis (scale 1-5, 5 = highest), perceived added diagnostic value (scale 1-5, 5 = highest), and interpretation time of multiplanar or 3-D VR images were compared using paired t-tests. Interobserver agreement was measured using the chance-corrected kappa coefficient. The final study population consisted of 28 children (15 boys and 13 girls; mean age: 5.2 months). Diagnostic accuracy based on 116 individual pulmonary veins for detection of proximal pulmonary vein stenosis was 72.4% (84 of 116) for axial MDCT images, 77.5% (90 of 116 cases) for multiplanar MDCT images, and 93% (108 of 116 cases) for 3-D VR images with significantly higher accuracy with 3-D VR compared to axial (z = 4.17, P < 0.001) and multiplanar (z = 3.34, P < 0.001) images. Confidence levels for detection of proximal pulmonary vein stenosis were significantly higher with 3-D VR images (mean level: 4.6) compared to axial MDCT images (mean level: 1.7) and multiplanar MDCT images (mean level: 2.0) (paired t-tests, P < 0.001). Thus, 3-D VR images (mean added diagnostic value: 4.7) were found to provide added diagnostic value for detecting proximal pulmonary vein stenosis (paired t-test, P < 0.001); however, multiplanar MDCT images did not provide added value (paired t-test, P = 0.89). Interpretation time was significantly longer and interobserver agreement was higher when using 3-D VR images than using axial MDCT images or MPR MDCT images for diagnosing proximal pulmonary vein stenosis (paired t-tests, P < 0.001). Use of 3-D VR images in the diagnosis of proximal pulmonary vein stenosis in children significantly increases accuracy, confidence level, added diagnostic value and interobserver agreement. Thus, the routine use of this technique should be encouraged despite its increased interpretation time.
-
SOFT: a synthetic synchrotron diagnostic for runaway electrons
NASA Astrophysics Data System (ADS)
Hoppe, M.; Embréus, O.; Tinguely, R. A.; Granetz, R. S.; Stahl, A.; Fülöp, T.
2018-02-01
Improved understanding of the dynamics of runaway electrons can be obtained by measurement and interpretation of their synchrotron radiation emission. Models for synchrotron radiation emitted by relativistic electrons are well established, but the question of how various geometric effects—such as magnetic field inhomogeneity and camera placement—influence the synchrotron measurements and their interpretation remains open. In this paper we address this issue by simulating synchrotron images and spectra using the new synthetic synchrotron diagnostic tool SOFT (Synchrotron-detecting Orbit Following Toolkit). We identify the key parameters influencing the synchrotron radiation spot and present scans in those parameters. Using a runaway electron distribution function obtained by Fokker-Planck simulations for parameters from an Alcator C-Mod discharge, we demonstrate that the corresponding synchrotron image is well-reproduced by SOFT simulations, and we explain how it can be understood in terms of the parameter scans. Geometric effects are shown to significantly influence the synchrotron spectrum, and we show that inherent inconsistencies in a simple emission model (i.e. not modeling detection) can lead to incorrect interpretation of the images.
-
A data-driven approach for quality assessment of radiologic interpretations.
Hsu, William; Han, Simon X; Arnold, Corey W; Bui, Alex At; Enzmann, Dieter R
2016-04-01
Given the increasing emphasis on delivering high-quality, cost-efficient healthcare, improved methodologies are needed to measure the accuracy and utility of ordered diagnostic examinations in achieving the appropriate diagnosis. Here, we present a data-driven approach for performing automated quality assessment of radiologic interpretations using other clinical information (e.g., pathology) as a reference standard for individual radiologists, subspecialty sections, imaging modalities, and entire departments. Downstream diagnostic conclusions from the electronic medical record are utilized as "truth" to which upstream diagnoses generated by radiology are compared. The described system automatically extracts and compares patient medical data to characterize concordance between clinical sources. Initial results are presented in the context of breast imaging, matching 18 101 radiologic interpretations with 301 pathology diagnoses and achieving a precision and recall of 84% and 92%, respectively. The presented data-driven method highlights the challenges of integrating multiple data sources and the application of information extraction tools to facilitate healthcare quality improvement. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
-
Rowe, Steven P; Deville, Curtiland; Paller, Channing; Cho, Steve Y; Fishman, Elliot K; Pomper, Martin G; Ross, Ashley E; Gorin, Michael A
2015-12-01
Prostate-specific membrane antigen (PSMA)-targeted PET imaging is an emerging technique for evaluating patients with prostate cancer (PCa) in a variety of clinical contexts. As with any new imaging modality, there are interpretive pitfalls that are beginning to be recognized. In this image report, we describe the findings in a 63-year-old male with biochemically recurrent PCa after radical prostatectomy who was imaged with 18 F-DCFPyL, a small molecule inhibitor of PSMA. Diffuse radiotracer uptake was noted throughout the sacrum, corresponding to imaging findings on contrast-enhanced CT, bone scan, and pelvic MRI consistent with Paget's disease of bone. The uptake of 18 F-DCFPyL in Paget's disease is most likely due to hyperemia and increased radiotracer delivery. In light of the overlap in patients affected by PCa and Paget's, it is important for nuclear medicine physicians and radiologists interpreting PSMA PET/CT scans to be aware of the potential for this diagnostic pitfall. Correlation to findings on conventional imaging such as diagnostic CT and bone scan can help confirm the diagnosis.
-
On the temperature and the interstellar nature of coronal gas observed by Copernicus
NASA Technical Reports Server (NTRS)
York, D. G.
1977-01-01
More detailed scans of ions expected in interstellar absorption at temperatures of 100,000 to 1 million K have been made with Copernicus in five stars: Alpha Vir, Beta Cen, Lambda Sco, Mu Col, and HD 28497. Preliminary data show that the absorption due to O VI is stationary compared with the velocities of stellar absorption in the spectrum of the spectroscopic binary Lambda Sco, thus demonstrating its nonstellar nature. Ionization temperatures interpreted using steady-state or time-dependent assumptions yield values of 280,000 to 700,000 K. There is some evidence that a range of temperatures consistent with this spread may in fact exist in Alpha Vir. For this limited sample of data, there is no clear evidence for a generic association of low-column-density H2 and the O VI absorption. It is concluded that the O VI absorption refers to regions with temperatures exceeding 250,000 K. The only UV diagnostic for the gas appears to be the O VI features, though C IV may be useful in some cases.
-
Correcting AUC for Measurement Error.
Rosner, Bernard; Tworoger, Shelley; Qiu, Weiliang
2015-12-01
Diagnostic biomarkers are used frequently in epidemiologic and clinical work. The ability of a diagnostic biomarker to discriminate between subjects who develop disease (cases) and subjects who do not (controls) is often measured by the area under the receiver operating characteristic curve (AUC). The diagnostic biomarkers are usually measured with error. Ignoring measurement error can cause biased estimation of AUC, which results in misleading interpretation of the efficacy of a diagnostic biomarker. Several methods have been proposed to correct AUC for measurement error, most of which required the normality assumption for the distributions of diagnostic biomarkers. In this article, we propose a new method to correct AUC for measurement error and derive approximate confidence limits for the corrected AUC. The proposed method does not require the normality assumption. Both real data analyses and simulation studies show good performance of the proposed measurement error correction method.
-
The perceived and actual diagnostic utility of veterinary cytological samples.
Skeldon, N; Dewhurst, E
2009-04-01
To establish the proportion of cytology samples sent to a commercial veterinary laboratory that yields diagnostically useful information in the context of current use and perceptions of cytology. Nine hundred and forty-five cytology submissions were retrospectively collected and categorised according to diagnostic utility. A survey into the use and perceptions of cytology was distributed at the British Small Animal Veterinary Association Congress 2008. A specific diagnosis was reached in 23.1 per cent of samples and a cytological diagnosis in 35.3 per cent. 22.4 per cent of samples yielded some useful information, but 19.2 per cent were unacceptable. Seventy-four participants in the survey took an average of 3.9 cytological samples per week, of which they examined 27.0 per cent in-house only, 21.6 per cent in-house before sending to an external laboratory and 51.4 per cent were sent externally without prior examination. "To obtain a definitive diagnosis" was the principal reason cited for performing cytology. Results suggest that cytology is underused and may be applied in an inappropriate context in the UK. It is hoped that illustrating the diagnostic outcome of samples received by a commercial laboratory will encourage increased, appropriate use of cytology.
-
Han, Yeji; Kim, Hyun Jung; Kong, Kyoung Ae; Kim, Soo Jung; Lee, Su Hwan; Ryu, Yon Ju; Lee, Jin Hwa; Kim, Yookyoung; Shim, Sung Shine
2018-01-01
Background Advances in bronchoscopy and CT-guided lung biopsy have improved the evaluation of small pulmonary lesions (PLs), leading to an increase in preoperative histological diagnosis. We aimed to evaluate the efficacy and safety of transbronchial lung biopsy using radial endobronchial ultrasound and virtual bronchoscopic navigation (TBLB-rEBUS&VBN) and CT-guided transthoracic needle biopsy (CT-TNB) for tissue diagnosis of small PLs. Methods A systematic search was performed in five electronic databases, including MEDLINE, EMBASE, Cochrane Library Central Register of Controlled Trials, Web of Science, and Scopus, for relevant studies in May 2016; the selected articles were assessed using meta-analysis. The articles were limited to those published after 2000 that studied small PLs ≤ 3 cm in diameter. Results From 7345 records, 9 articles on the bronchoscopic (BR) approach and 15 articles on the percutaneous (PC) approach were selected. The pooled diagnostic yield was 75% (95% confidence interval [CI], 69–80) using the BR approach and 93% (95% CI, 90–96) using the PC approach. For PLs ≤ 2 cm, the PC approach (pooled diagnostic yield: 92%, 95% CI: 88–95) was superior to the BR approach (66%, 95% CI: 55–76). However, for PLs > 2 cm but ≤ 3 cm, the diagnostic yield using the BR approach was improved to 81% (95% CI, 75–85). Complications of pneumothorax and hemorrhage were rare with the BR approach but common with the PC approach. Conclusions CT-TNB was superior to TBLB-rEBUS&VBN for the evaluation of small PLs. However, for lesions greater than 2 cm, the BR approach may be considered considering its diagnostic yield of over 80% and the low risk of procedure-related complications. PMID:29357388
-
Buscaglia, Jonathan M; Nagula, Satish; Jayaraman, Vijay; Robbins, David H; Vadada, Deepak; Gross, Seth A; DiMaio, Christopher J; Pais, Shireen; Patel, Kal; Sejpal, Divyesh V; Kim, Michelle K
2012-06-01
EUS-FNA often fails to make a definitive diagnosis in the evaluation of subepithelial lesions. The addition of jumbo biopsy forceps has the potential to improve diagnostic yield, but published series are limited. To assess the likelihood of definitive diagnosis for subepithelial lesions by using jumbo biopsy forceps during EUS examination. Pooled retrospective analysis. 6 tertiary referral centers. All patients having undergone EUS examination for a subepithelial lesion in which jumbo biopsy forceps were used for tissue acquisition. Diagnostic yield of jumbo biopsy forceps use, complication rates, and comparison of diagnostic yield with that of EUS-FNA. A total of 129 patients underwent EUS with jumbo biopsy forceps; 31 patients (24%) had simultaneous EUS-FNA. The lesion locations were stomach (n = 98), esophagus (n = 14), duodenum (n = 11), colon (n = 5), and jejunum (n = 1). The average lesion size was 14.9 mm ± 9.3 mm. Overall, definitive diagnosis was obtained in 87 of 129 patients (67.4%) by using either method. A definitive diagnosis was provided by jumbo biopsy forceps use in 76 of 129 patients (58.9%) and by FNA in 14 of 31 patients (45.1%) (P = .175). The results in third-layer lesions were definitive with jumbo biopsy forceps in 56 of 86 lesions (65.1%) and with FNA in 6 of 16 lesions (37.5%) (P = .047). For fourth-layer lesions, the results with jumbo biopsy forceps were definitive in 10 of 25 (40.0%) and with FNA in 8 of 14 (57.1%) (P = .330). Forty-five of 129 patients (34.9%) experienced significant bleeding after biopsy with jumbo forceps and required some form of endoscopic hemostasis. Retrospective study. Jumbo forceps are a useful tool for the definitive diagnosis of subepithelial lesions. The greatest benefit appears to be with third-layer (submucosal) lesions. The risk of bleeding is significant. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.
-
Wang, Yu Tien; Tai, Ling Fung; Yazaki, Etsuro; Jafari, Jafar; Sweis, Rami; Tucker, Emily; Knowles, Kevin; Wright, Jeff; Ahmad, Saqib; Kasi, Madhavi; Hamlett, Katharine; Fox, Mark R; Sifrim, Daniel
2015-09-01
Management of patients with dysphagia, regurgitation, and related symptoms after antireflux surgery is challenging. This prospective, case-control study tested the hypothesis that compared with standard high-resolution manometry (HRM) with single water swallows (SWS), adding multiple water swallows (MWS) and a solid test meal increases diagnostic yield and clinical impact of physiological investigations. Fifty-seven symptomatic and 12 asymptomatic patients underwent HRM with SWS, MWS, and a solid test meal. Dysphagia and reflux were assessed by validated questionnaires. Diagnostic yield of standard and full HRM studies with 24-hour pH-impedance monitoring was compared. Pneumatic dilatation was performed for outlet obstruction on HRM studies. Clinical outcome was assessed by questionnaires and an analogue scale with "satisfactory" defined as at least 40% symptom improvement requiring no further treatment. Postoperative esophagogastric junction pressure was similar in all groups. Abnormal esophagogastric junction morphology (double high pressure band) was more common in symptomatic than in control patients (13 of 57 vs 0 of 12, P = .004). Diagnostic yield of HRM was 11 (19%), 11 (19%), and 33 of 57 (58%), with SWS, MWS, and solids, respectively (P < .001); it was greatest for solids in patients with dysphagia (19 of 27, 70%). Outlet obstruction was present in 4 (7%), 11 (19%), and 15 of 57 patients (26%) with SWS, MWS, and solids, respectively (P < .009). No asymptomatic control had clinically relevant dysfunction on solid swallows. Dilatation was performed in 12 of 15 patients with outlet obstruction during the test meal. Symptom response was satisfactory, good, or excellent in 7 of 12 (58%) with no serious complications. The addition of MWS and a solid test meal increases the diagnostic yield of HRM studies in patients with symptoms after fundoplication and identifies additional patients with outlet obstruction who benefit from endoscopic dilatation. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.
-
NASA Technical Reports Server (NTRS)
1978-01-01
The author has identified the following significant results. Yield modelling for crop production estimation derived a means of predicting the within-a-year yield and the year-to-year variability of yield over some fixed or randomly located unit of area. Preliminary studies indicated that the requirements for interpreting LANDSAT data for yield may be sufficiently similar to those of signature extension that it is feasible to investigate the automated estimation of production. The concept of an advanced yield model consisting of both spectral and meteorological components was endorsed. Rationale for using meteorological parameters originated from known between season and near harvest dynamics in crop environmental-condition-yield relationships.
-
Mass properties measurement system: Dynamics and statics measurements
NASA Technical Reports Server (NTRS)
Doty, Keith L.
1993-01-01
This report presents and interprets experimental data obtained from the Mass Properties Measurement System (MPMS). Statics measurements yield the center-of-gravity of an unknown mass and dynamics measurements yield its inertia matrix. Observations of the MPMS performance has lead us to specific design criteria and an understanding of MPMS limitations.
-
A generalization of the theory of fringe patterns containing displacement information
NASA Astrophysics Data System (ADS)
Sciammarella, C. A.; Bhat, G.
The theory that provides the interpretation of interferometric fringes as frequency modulated signals, is used to show that the electrooptical system used to analyze fringe patterns can be considered as a simultaneous Fourier spectrum analyzer. This interpretation generalizes the quasi-heterodyning techniques. It is pointed out that the same equations that yield the discrete Fourier transform as summations, yield correct values for a reduced number of steps. Examples of application of the proposed technique to electronic holography are given. It is found that for a uniform field the standard deviation of the individual readings is 1/20 of the fringe spacing.
-
What We Do and Do Not Know about Teaching Medical Image Interpretation.
Kok, Ellen M; van Geel, Koos; van Merriënboer, Jeroen J G; Robben, Simon G F
2017-01-01
Educators in medical image interpretation have difficulty finding scientific evidence as to how they should design their instruction. We review and comment on 81 papers that investigated instructional design in medical image interpretation. We distinguish between studies that evaluated complete offline courses and curricula, studies that evaluated e-learning modules, and studies that evaluated specific educational interventions. Twenty-three percent of all studies evaluated the implementation of complete courses or curricula, and 44% of the studies evaluated the implementation of e-learning modules. We argue that these studies have encouraging results but provide little information for educators: too many differences exist between conditions to unambiguously attribute the learning effects to specific instructional techniques. Moreover, concepts are not uniformly defined and methodological weaknesses further limit the usefulness of evidence provided by these studies. Thirty-two percent of the studies evaluated a specific interventional technique. We discuss three theoretical frameworks that informed these studies: diagnostic reasoning, cognitive schemas and study strategies. Research on diagnostic reasoning suggests teaching students to start with non-analytic reasoning and subsequently applying analytic reasoning, but little is known on how to train non-analytic reasoning. Research on cognitive schemas investigated activities that help the development of appropriate cognitive schemas. Finally, research on study strategies supports the effectiveness of practice testing, but more study strategies could be applicable to learning medical image interpretation. Our commentary highlights the value of evaluating specific instructional techniques, but further evidence is required to optimally inform educators in medical image interpretation.
-
Hanemaaijer, Nicolien M; Sikkema-Raddatz, Birgit; van der Vries, Gerben; Dijkhuizen, Trijnie; Hordijk, Roel; van Essen, Anthonie J; Veenstra-Knol, Hermine E; Kerstjens-Frederikse, Wilhelmina S; Herkert, Johanna C; Gerkes, Erica H; Leegte, Lamberta K; Kok, Klaas; Sinke, Richard J; van Ravenswaaij-Arts, Conny M A
2012-01-01
The correct interpretation of copy number gains in patients with developmental delay and multiple congenital anomalies is hampered by the large number of copy number variations (CNVs) encountered in healthy individuals. The variable phenotype associated with copy number gains makes interpretation even more difficult. Literature shows that inheritence, size and presence in healthy individuals are commonly used to decide whether a certain copy number gain is pathogenic, but no general consensus has been established. We aimed to develop guidelines for interpreting gains detected by array analysis using array CGH data of 300 patients analysed with the 105K Agilent oligo array in a diagnostic setting. We evaluated the guidelines in a second, independent, cohort of 300 patients. In the first 300 patients 797 gains of four or more adjacent oligonucleotides were observed. Of these, 45.4% were de novo and 54.6% were familial. In total, 94.8% of all de novo gains and 87.1% of all familial gains were concluded to be benign CNVs. Clinically relevant gains ranged from 288 to 7912 kb in size, and were significantly larger than benign gains and gains of unknown clinical relevance (P<0.001). Our study showed that a threshold of 200 kb is acceptable in a clinical setting, whereas heritability does not exclude a pathogenic nature of a gain. Evaluation of the guidelines in the second cohort of 300 patients revealed that the interpretation guidelines were clear, easy to follow and efficient. PMID:21934709
-
ERIC Educational Resources Information Center
McGrew, Susan G.; Peters, Brittany R.; Crittendon, Julie A.; Veenstra-VanderWeele, Jeremy
2012-01-01
Genetic testing is recommended for patients with ASD; however specific recommendations vary by specialty. American Academy of Pediatrics and American Academy of Neurology guidelines recommend G-banded karyotype and Fragile X DNA. The American College of Medical Genetics recommends Chromosomal Microarray Analysis (CMA). We determined the yield of…
-
[Clinical importance of thyroid gland cytology].
Ting, S; Synoracki, S; Bockisch, A; Führer, D; Schmid, K W
2015-11-01
The cytological evaluation of fine needle biopsies (FNB) of the thyroid gland crucially depends on a close cooperation between clinicians and cytopathologists. Scintigraphy, sonography as well as clinical data and patient history are necessary for a correct interpretation of the indications for FNB; moreover, these data are of outstanding importance for cytopathologists for the correct interpretation of the cytomorphological findings. This overview describes the present standards in the acquisition, technical workup and cytopathological interpretation of thyroid gland tissue obtained by FNB, particularly focusing on the rapidly growing relevance of additional molecular pathological investigations to increase the diagnostic accuracy of thyroid FNB.
-
Huang, Ziling; Yi, Xianghua; Luo, Benfang; Zhu, Jian; Wu, Yunjin; Jiang, Wenxia; Chu, Haiqing; Yang, Zhongmin; Li, Shuai; Zhu, Hailong; Zhang, Suxia; Zhang, Lanjing; Zeng, Yu
2016-01-01
Pulmonary alveolar proteinosis (PAP) is a rare diffuse lung disease characterized by the accumulation of intra-alveolar lipoprotein-like surfactants. Lung core biopsy and bronchoalveolar lavage (BAL) fluid are currently the two major sources of sampling for diagnosis. In the present study, we assessed the value of induced sputum in diagnosing PAP by transmission electron microscopy and examined the PAP 2-year death rate in Asians. Transmission electron microscopy was performed on the samples from 17 patients with PAP, 13 patients with inflammatory lung diseases, and 13 healthy adults. The PAP patients were followed up for 3-156 months, and inflammatory lung diseases patients or healthy adults for 12-36 months. The ultrastructural features including diagnostic lamellar bodies of induced sputum deposition (ISD) samples were similar to that of the BAL fluid sediment. However, the rates of lamellar bodies were 73.7% in the ISD group, significantly higher than the spontaneous sputum deposition (SSD) group (42.1%, P < .0487) and similar to the BAL sediment (76.2%) and the lung biopsy (54.5%) groups. The overall 2-year death rate of our PAP patients was 17.6% (3/17), not statistically different from the healthy adults and patients with inflammatory diseases (0/13, P = .237 for both). ISD may be the preferred non-invasive sampling method for diagnosing PAP by electronic microscopy because of the higher diagnostic yield than SSD. The diagnostic yields of this noninvasive method were similar to that of lung core biopsy and BAL.
-
Yoon, Min A; Kim, Se Hyung; Lee, Jeong Min; Woo, Hyoun Sik; Lee, Eun Sun; Ahn, Se Jin; Han, Joon Koo
2012-01-01
To evaluate the diagnostic performance of computed tomography (CT) colonography (CTC) reconstructed with different levels of adaptive statistical iterative reconstruction (ASiR, GE Healthcare) and Veo (model-based iterative reconstruction, GE Healthcare) at various tube currents in detection of polyps in porcine colon phantoms. Five porcine colon phantoms with 46 simulated polyps were scanned at different radiation doses (10, 30, and 50 mA s) and were reconstructed using filtered back projection (FBP), ASiR (20%, 40%, and 60%) and Veo. Eleven data sets for each phantom (10-mA s FBP, 10-mA s 20% ASiR, 10-mA s 40% ASiR, 10-mA s 60% ASiR, 10-mA s Veo, 30-mA s FBP, 30-mA s 20% ASiR, 30-mA s 40% ASiR, 30-mA s 60% ASiR, 30-mA s Veo, and 50-mA s FBP) yielded a total of 55 data sets. Polyp detection sensitivity and confidence level of 2 independent observers were evaluated with the McNemar test, the Fisher exact test, and receiver operating characteristic curve analysis. Comparative analyses of overall image quality score, measured image noise, and interpretation time were also performed. Per-polyp detection sensitivities and specificities were highest in 10-mA s Veo, 30-mA s FBP, 30-mA s 60% ASiR, and 50-mA s FBP (sensitivity, 100%; specificity, 100%). The area-under-the-curve values for the overall performance of each data set was also highest (1.000) at 50-mA s FBP, 30-mA s FBP, 30-mA s 60% ASiR, and 10-mA s Veo. Images reconstructed with ASiR showed statistically significant improvement in per-polyp detection sensitivity as the percent level of per-polyp sensitivity increased (10-mA s FBP vs 10-mA s 20% ASiR, P = 0.011; 10-mA s FBP vs 10-mA s 40% ASiR, P = 0.000; 10-mA s FBP vs 10-mA s 60% ASiR, P = 0.000; 10-mA s 20% ASiR vs 40% ASiR, P = 0.034). Overall image quality score was highest at 30-mA s Veo and 50-mA s FBP. The quantitative measurement of the image noise was lowest at 30-mA s Veo and second lowest at 10-mA s Veo. There was a trend of decrease in time required for image interpretation as the percent level of ASiR increased, and ASiR or Veo was used instead of FBP. However, differences from comparative analyses of overall image quality score, measured image noise, and interpretation time did not reach statistical significance. ASiR and Veo showed improved diagnostic performance with excellent sensitivity and specificity with less image noise and good image quality compared with FBP reconstruction of same radiation dose. Our study confirmed feasibility of low-dose CTC with iterative reconstruction as a promising screening tool with excellent diagnostic performance similar to that of the standard-dose CTC with FBP.
-
Computer-Interpreted Electrocardiograms: Benefits and Limitations.
Schläpfer, Jürg; Wellens, Hein J
2017-08-29
Computerized interpretation of the electrocardiogram (CIE) was introduced to improve the correct interpretation of the electrocardiogram (ECG), facilitating health care decision making and reducing costs. Worldwide, millions of ECGs are recorded annually, with the majority automatically analyzed, followed by an immediate interpretation. Limitations in the diagnostic accuracy of CIE were soon recognized and still persist, despite ongoing improvement in ECG algorithms. Unfortunately, inexperienced physicians ordering the ECG may fail to recognize interpretation mistakes and accept the automated diagnosis without criticism. Clinical mismanagement may result, with the risk of exposing patients to useless investigations or potentially dangerous treatment. Consequently, CIE over-reading and confirmation by an experienced ECG reader are essential and are repeatedly recommended in published reports. Implementation of new ECG knowledge is also important. The current status of automated ECG interpretation is reviewed, with suggestions for improvement. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
-
What we need to know when performing and interpreting US elastography
Park, So Hyun; Kim, So Yeon; Suh, Chong Hyun; Lee, Seung Soo; Kim, Kyoung Won; Lee, So Jung; Lee, Moon-Gyu
2016-01-01
According to the increasing need for accurate staging of hepatic fibrosis, the ultrasound (US) elastography techniques have evolved significantly over the past two decades. Currently, US elastography is increasingly used in clinical practice. Previously published studies have demonstrated the excellent diagnostic performance of US elastography for the detection and staging of liver fibrosis. Although US elastography may seem easy to perform and interpret, there are many technical and clinical factors which can affect the results of US elastography. Therefore, clinicians who are involved with US elastography should be aware of these factors. The purpose of this article is to present a brief overview of US techniques with the relevant technology, the clinical indications, diagnostic performance, and technical and biological factors which should be considered in order to avoid misinterpretation of US elastography results. PMID:27729637
-
Koa-Wing, Michael; Nakagawa, Hiroshi; Luther, Vishal; Jamil-Copley, Shahnaz; Linton, Nick; Sandler, Belinda; Qureshi, Norman; Peters, Nicholas S; Davies, D Wyn; Francis, Darrel P; Jackman, Warren; Kanagaratnam, Prapa
2015-11-15
Ripple Mapping (RM) is designed to overcome the limitations of existing isochronal 3D mapping systems by representing the intracardiac electrogram as a dynamic bar on a surface bipolar voltage map that changes in height according to the electrogram voltage-time relationship, relative to a fiduciary point. We tested the hypothesis that standard approaches to atrial tachycardia CARTO™ activation maps were inadequate for RM creation and interpretation. From the results, we aimed to develop an algorithm to optimize RMs for future prospective testing on a clinical RM platform. CARTO-XP™ activation maps from atrial tachycardia ablations were reviewed by two blinded assessors on an off-line RM workstation. Ripple Maps were graded according to a diagnostic confidence scale (Grade I - high confidence with clear pattern of activation through to Grade IV - non-diagnostic). The RM-based diagnoses were corroborated against the clinical diagnoses. 43 RMs from 14 patients were classified as Grade I (5 [11.5%]); Grade II (17 [39.5%]); Grade III (9 [21%]) and Grade IV (12 [28%]). Causes of low gradings/errors included the following: insufficient chamber point density; window-of-interest<100% of cycle length (CL); <95% tachycardia CL mapped; variability of CL and/or unstable fiducial reference marker; and suboptimal bar height and scar settings. A data collection and map interpretation algorithm has been developed to optimize Ripple Maps in atrial tachycardias. This algorithm requires prospective testing on a real-time clinical platform. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
-
Acquired pathology of the pediatric spine and spinal cord.
Palasis, Susan; Hayes, Laura L
2015-09-01
Pediatric spine pathology poses a diagnostic challenge for radiologists. Acquired spine pathology often yields nonspecific signs and symptoms in children, especially in the younger age groups, and diagnostic delay can carry significant morbidity. This review is focused on some of the more common diagnostic dilemmas we face when attempting to evaluate and diagnose acquired pediatric spine anomalies in daily practice. An understanding of some of the key differentiating features of these disease processes in conjunction with pertinent history, physical exam, and advanced imaging techniques can indicate the correct diagnosis.
-
Current approach in the diagnosis and management of posterior uveitis
Sudharshan, S; Ganesh, Sudha K; Biswas, Jyotrimay
2010-01-01
Posterior uveitic entities are varied entities that are infective or non-infective in etiology. They can affect the adjacent structures such as the retina, vitreous, optic nerve head and retinal blood vessels. Thorough clinical evaluation gives a clue to the diagnosis while ancillary investigations and laboratory tests assist in confirming the diagnosis. Newer evolving techniques in the investigations and management have increased the diagnostic yield. In case of diagnostic dilemma, intraocular fluid evaluation for polymerase chain testing for the genome and antibody testing against the causative agent provide greater diagnostic ability. PMID:20029144
-
Nikkels, A F; Debrus, S; Sadzot-Delvaux, C; Piette, J; Rentier, B; Piérard, G E
1995-12-01
Early and specific recognition of varicella zoster virus (VZV) infection is of vital concern in immunocompromised patients. The aim of this study was to compare the diagnostic accuracy of histochemical and immunohistochemical identification of the VZV ORF63 encoded protein (IE63) and of the VZV late protein gE on smears and formalin-fixed paraffin-embedded skin sections taken from lesions clinically diagnosed as varicella (n = 15) and herpes zoster (n = 51). Microscopic examinations of Tzanck smears and skin sections yielded a diagnostic accuracy of Herpesviridae infections in 66.7% (10/15) and 92.3% (12/13) of varicella, and 74.4% (29/39) and 87.8% (43/49) of herpes zoster, respectively. Immunohistochemistry applied to varicella provided a type-specific virus diagnostic accuracy of 86.7% (13/15; IE63) and 100% (15/15; gE) on smears, and of 92.3% for both VZV proteins on skin sections. In herpes zoster, the diagnostic accuracy of immunohistochemistry reached 92.3% (36/39; IE63) and 94.9% (37/39; gE) on smears, and 91.7% (44/48; IE63) and 91.8% (45/49; gE) on skin sections. These findings indicate that the immunohistochemical detection of IE63 and gE on both smears and skin sections yields a higher specificity and sensitivity than standard microscopic assessments.
-
Murari, A; Angelone, M; Bonheure, G; Cecil, E; Craciunescu, T; Darrow, D; Edlington, T; Ericsson, G; Gatu-Johnson, M; Gorini, G; Hellesen, C; Kiptily, V; Mlynar, J; Perez von Thun, C; Pillon, M; Popovichev, S; Syme, B; Tardocchi, M; Zoita, V L
2010-10-01
Notwithstanding the advances of the past decades, significant developments are still needed to satisfactorily diagnose “burning plasmas.” D–T plasmas indeed require a series of additional measurements for the optimization and control of the configuration: the 14 MeV neutrons, the isotopic composition of the main plasma, the helium ash, and the redistribution and losses of the alpha particles. Moreover a burning plasma environment is in general much more hostile for diagnostics than purely deuterium plasmas. Therefore, in addition to the development and refinement of new measuring techniques, technological advances are also indispensable for the proper characterization of the next generation of devices. On JET an integrated program of diagnostic developments, for JET future and in preparation for ITER, has been pursued and many new results are now available. In the field of neutron detection, the neutron spectra are now routinely measured in the energy range of 1–18 MeV by a time of flight spectrometer and they have allowed studying the effects of rf heating on the fast ions. A new analysis method for the interpretation of the neutron cameras measurements has been refined and applied to the data of the last trace tritium campaign (TTE). With regard to technological upgrades, chemical vapor deposition diamond detectors have been qualified both as neutron counters and as neutron spectrometers, with a potential energy resolution of about one percent. The in situ calibration of the neutron diagnostics, in preparation for the operation with the ITER-like wall, is also promoting important technological developments. With regard to the fast particles, for the first time the temperature of the fast particle tails has been obtained with a new high purity Germanium detector measuring the gamma emission spectrum from the plasma. The effects of toroidal Alfven eigenmodes modes and various MHD instabilities on the confinement of the fast particles have been determined with a combination of gamma ray cameras, neutral particle analyzers, scintillator probe, and Faraday cups. From a more technological perspective, various neutron filters have been tested to allow measurement of the gamma ray emission also at high level of neutron yield.
-
New developments in the diagnostics for the fusion products on JET in preparation for ITER (invited)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murari, A.; Angelone, M.; Pillon, M.
Notwithstanding the advances of the past decades, significant developments are still needed to satisfactorily diagnose ''burning plasmas.'' D-T plasmas indeed require a series of additional measurements for the optimization and control of the configuration: the 14 MeV neutrons, the isotopic composition of the main plasma, the helium ash, and the redistribution and losses of the alpha particles. Moreover a burning plasma environment is in general much more hostile for diagnostics than purely deuterium plasmas. Therefore, in addition to the development and refinement of new measuring techniques, technological advances are also indispensable for the proper characterization of the next generation ofmore » devices. On JET an integrated program of diagnostic developments, for JET future and in preparation for ITER, has been pursued and many new results are now available. In the field of neutron detection, the neutron spectra are now routinely measured in the energy range of 1-18 MeV by a time of flight spectrometer and they have allowed studying the effects of rf heating on the fast ions.A new analysis method for the interpretation of the neutron cameras measurements has been refined and applied to the data of the last trace tritium campaign (TTE). With regard to technological upgrades, chemical vapor deposition diamond detectors have been qualified both as neutron counters and as neutron spectrometers, with a potential energy resolution of about one percent. The in situ calibration of the neutron diagnostics, in preparation for the operation with the ITER-like wall, is also promoting important technological developments. With regard to the fast particles, for the first time the temperature of the fast particle tails has been obtained with a new high purity Germanium detector measuring the gamma emission spectrum from the plasma. The effects of toroidal Alfven eigenmodes modes and various MHD instabilities on the confinement of the fast particles have been determined with a combination of gamma ray cameras, neutral particle analyzers, scintillator probe, and Faraday cups. From a more technological perspective, various neutron filters have been tested to allow measurement of the gamma ray emission also at high level of neutron yield.« less
-
Dependency Distance Differences across Interpreting Types: Implications for Cognitive Demand
Liang, Junying; Fang, Yuanyuan; Lv, Qianxi; Liu, Haitao
2017-01-01
Interpreting is generally recognized as a particularly demanding language processing task for the cognitive system. Dependency distance, the linear distance between two syntactically related words in a sentence, is an index of sentence complexity and is also able to reflect the cognitive constraints during various tasks. In the current research, we examine the difference in dependency distance among three interpreting types, namely, simultaneous interpreting, consecutive interpreting and read-out translated speech based on a treebank comprising these types of interpreting output texts with dependency annotation. Results show that different interpreting renditions yield different dependency distances, and consecutive interpreting texts entail the smallest dependency distance other than those of simultaneous interpreting and read-out translated speech, suggesting that consecutive interpreting bears heavier cognitive demands than simultaneous interpreting. The current research suggests for the first time that interpreting is an extremely demanding cognitive task that can further mediate the dependency distance of output sentences. Such findings may be due to the minimization of dependency distance under cognitive constraints. PMID:29312027
-
The role of bronchoscopy in the diagnosis of airway disease
Dixon, Jennifer; Tieu, Brandon H.
2016-01-01
Endoscopy of the airway is a valuable tool for the evaluation and management of airway disease. It can be used to evaluate many different bronchopulmonary diseases including airway foreign bodies, tumors, infectious and inflammatory conditions, airway stenosis, and bronchopulmonary hemorrhage. Traditionally, options for evaluation were limited to flexible and rigid bronchoscopy. Recently, more sophisticated technology has led to the development of endobronchial ultrasound (EBUS) and electromagnetic navigational bronchoscopy (ENB). These technological advances, combined with increasing provider experience have resulted in a higher diagnostic yield with endoscopic biopsies. This review will focus on the role of bronchoscopy, including EBUS, ENB, and rigid bronchoscopy in the diagnosis of bronchopulmonary diseases. In addition, it will cover the anesthetic considerations, equipment, diagnostic yield, and potential complications. PMID:28149583
-
Lazaridis, Konstantinos N; Schahl, Kimberly A; Cousin, Margot A; Babovic-Vuksanovic, Dusica; Riegert-Johnson, Douglas L; Gavrilova, Ralitza H; McAllister, Tammy M; Lindor, Noralane M; Abraham, Roshini S; Ackerman, Michael J; Pichurin, Pavel N; Deyle, David R; Gavrilov, Dimitar K; Hand, Jennifer L; Klee, Eric W; Stephens, Michael C; Wick, Myra J; Atkinson, Elizabeth J; Linden, David R; Ferber, Matthew J; Wieben, Eric D; Farrugia, Gianrico
2016-03-01
To describe the experience and outcome of performing whole-exome sequencing (WES) for resolution of patients on a diagnostic odyssey in the first 18 months of an individualized medicine clinic (IMC). The IMC offered WES to physicians of Mayo Clinic practice for patients with suspected genetic disease. DNA specimens of the proband and relatives were submitted to WES laboratories. We developed the Genomic Odyssey Board with multidisciplinary expertise to determine the appropriateness for IMC services, review WES reports, and make the final decision about whether the exome findings explain the disease. This study took place from September 30, 2012, to March 30, 2014. In the first 18 consecutive months, the IMC received 82 consultation requests for patients on a diagnostic odyssey. The Genomic Odyssey Board deferred 7 cases and approved 75 cases to proceed with WES. Seventy-one patients met with an IMC genomic counselor. Fifty-one patients submitted specimens for WES testing, and the results have been received for all. There were 15 cases in which a diagnosis was made on the basis of WES findings; thus, the positive diagnostic yield of this practice was 29%. The mean cost per patient for this service was approximately $8000. Medicaid supported 27% of the patients, and 38% of patients received complete or partial insurance coverage. The significant diagnostic yield, moderate cost, and notable health marketplace acceptance for WES compared with conventional genetic testing make the former method a rational diagnostic approach for patients on a diagnostic odyssey. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
-
Taif, Sawsan; Tufail, Fatma; Alnuaimi, Ahmed Sameer
2016-06-01
The aim of this study is to assess mammography performance in Oman by estimating the breast cancer rate and the positive predictive value (PPV) with the influence of some variables. This cross-sectional study was conducted on mammograms done in one of the three main breast imaging centers in Oman between January 2008 and July 2012. Diagnostic and screening groups were identified and assessed separately. Rate of abnormal mammograms, rate of breast cancer and the PPV were estimated according to Breast Imaging Reporting and Data System (BIRADS) score, presence of breast lump and patient's age. Total of 653 mammograms were included, 254 diagnostic and 399 screening. Abnormal mammograms (BIRADS 4 and 5) form 31.9% of the diagnostic examinations compared with 6.8% of screening examinations. Breast cancer was present in 17.9% of the diagnostic compared with 1.0% of the screening group. The PPV of BIRADS 5 was 94.1%, and for BIRADS 4 was 37.1 and 26.7% for diagnostic and screening studies. Overall PPV for abnormal mammograms was 65.2% in the diagnostic and 26.7% in the screening group. Mammography PPV shows positive association with age (P = 0.039) while presence of breast lump has no significant effect on the PPV (P = 0.38). BIRADS 5 score was found to have a high cancer yield making it a strong predictor of cancer. Different results were obtained in the diagnostic compared with screening mammography with higher rates of abnormal mammograms and breast cancer. Mammography performance should be better in the older women. © 2014 Wiley Publishing Asia Pty Ltd.
-
CT fluoroscopy-guided core needle biopsy of anterior mediastinal masses.
Iguchi, T; Hiraki, T; Matsui, Y; Fujiwara, H; Sakurai, J; Masaoka, Y; Uka, M; Tanaka, T; Gobara, H; Kanazawa, S
2018-02-01
To retrospectively evaluate the safety, diagnostic yield, and risk factors of diagnostic failure of computed tomography (CT) fluoroscopy-guided biopsies of anterior mediastinal masses. Biopsy procedures and results of anterior mediastinal masses in 71 patients (32 women/39 men; mean [±standard deviation] age, 53.8±20.0years; range, 14-88years) were analyzed. Final diagnoses were based on surgical outcomes, imaging findings, or clinical follow-up findings. The biopsy results were compared with the final diagnosis, and the biopsy procedures grouped by pathologic findings into diagnostic success and failure groups. Multiple putative risk factors for diagnostic failure were then assessed. Seventy-one biopsies (71 masses; mean size, 67.5±27.3mm; range 8.6-128.2mm) were analyzed. We identified 17 grade 1 and one grade 2 adverse events (25.4% overall) according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Sixty-nine biopsies (97.2%) provided samples fit for pathologic analysis. Diagnostic failure was found for eight (11.3%) masses; the 63 masses diagnosed successfully included thymic carcinoma (n=17), lung cancer (n=14), thymoma (n=12), malignant lymphoma (n=11), germ cell tumor (n=3), and others (n=6). Using a thinner needle (i.e., a 20-gauge needle) was the sole significant risk factor for diagnostic failure (P=0.039). CT fluoroscopy-guided biopsy of anterior mediastinal masses was safe and had a high diagnostic yield; however, using a thinner biopsy needle significantly increased the risk of a failed diagnosis. Copyright © 2017 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.
-
Helland, Gregg; Gaspari, Romolo; Licciardo, Samuel; Sanseverino, Alexandra; Torres, Ulises; Emhoff, Timothy; Blehar, David
2016-10-01
Ultrasound (US) has been shown to be effective at identifying a pneumothorax (PTX); however, the additional value of adding multiple views has not been studied. Single- and four-view protocols have both been described in the literature. The objective of this study was to compare the diagnostic accuracy of single-view versus four-view lung US to detect clinically significant PTX in trauma patients. This was a randomized, prospective trial on trauma patients. Adult patients with acute traumatic injury undergoing computed tomography (CT) scan of the chest were eligible for enrollment. Patients were randomized to a single view or four views of each hemithorax prior to any imaging. USs were performed and interpreted by credentialed physicians using a 7.5-Mhz linear array transducer on a portable US machine with digital clips recorded for later review. Attending radiologist interpretation of the chest CT was reviewed for presence or absence of PTX with descriptions of small foci of air or minimal PTX categorized as clinically insignificant. A total of 260 patients were enrolled over a 2-year period. A total of 139 patients received a single view of each chest wall and 121 patients received four views. There were a total of 49 patients that had a PTX (19%), and 29 of these were clinically significant (11%). In diagnosis of any PTX, both single-view and four-view techniques showed poor sensitivity (54.2 and 68%) but high specificity (99 and 98%). For clinically significant PTX, single-view US demonstrated a sensitivity of 93% (95% confidence interval [CI] = 64.1% to 99.6%) and a specificity of 99.2% (95% CI = 95.5% to 99.9%), with sensitivity of 93.3% (95% CI = 66% to 99.7%) and specificity of 98% (95% CI = 92.1% to 99.7%) for four views. Single-view and four-view chest wall USs demonstrate comparable sensitivity and specificity for PTX. The additional time to obtain four views should be weighed against the absence of additional diagnostic yield over a single view when using US to identify a clinically significant PTX. © 2016 by the Society for Academic Emergency Medicine.
-
Influences of Radiology Trainees on Screening Mammography Interpretation.
Hawley, Jeffrey R; Taylor, Clayton R; Cubbison, Alyssa M; Erdal, B Selnur; Yildiz, Vedat O; Carkaci, Selin
2016-05-01
Participation of radiology trainees in screening mammographic interpretation is a critical component of radiology residency and fellowship training. The aim of this study was to investigate and quantify the effects of trainee involvement on screening mammographic interpretation and diagnostic outcomes. Screening mammograms interpreted at an academic medical center by six dedicated breast imagers over a three-year period were identified, with cases interpreted by an attending radiologist alone or in conjunction with a trainee. Trainees included radiology residents, breast imaging fellows, and fellows from other radiology subspecialties during breast imaging rotations. Trainee participation, patient variables, results of diagnostic evaluations, and pathology were recorded. A total of 47,914 mammograms from 34,867 patients were included, with an overall recall rate for attending radiologists reading alone of 14.7% compared with 18.0% when involving a trainee (P < .0001). Overall cancer detection rate for attending radiologists reading alone was 5.7 per 1,000 compared with 5.2 per 1,000 when reading with a trainee (P = .517). When reading with a trainee, dense breasts represented a greater portion of recalls (P = .0001), and more frequently, greater than one abnormality was described in the breast (P = .013). Detection of ductal carcinoma in situ versus invasive carcinoma or invasive cancer type was not significantly different. The mean size of cancers in patients recalled by attending radiologists alone was smaller, and nodal involvement was less frequent, though not statistically significantly. These results demonstrate a significant overall increase in recall rate when interpreting screening mammograms with radiology trainees, with no change in cancer detection rate. Radiology faculty members should be aware of this potentiality and mitigate tendencies toward greater false positives. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.
-
NASA Astrophysics Data System (ADS)
Purnamasari, L.; Iskandar, H. H. B.; Makes, B. N.
2017-08-01
In digitized radiography techniques, adjusting the image enhancement can improve the subjective image quality by optimizing the brightness and contrast for diagnostic needs. To determine the value range of image enhancement (brightness and contrast) on chronic apical abscess and apical granuloma interpretation. 30 periapical radiographs that diagnosed chronic apical abscess and 30 that diagnosed apical granuloma were adjusted by changing brightness and contrast values. The value range of brightness and contrast adjustment that can be tolerated in radiographic interpretations of chronic apical abscess and apical granuloma spans from -10 to +10. Brightness and contrast adjustments on digital radiographs do not affect the radiographic interpretation of chronic apical abscess and apical granuloma if conducted within the value range.
-
Iridology: A systematic review.
Ernst, E
1999-02-01
Iridologists claim to be able to diagnose medical conditions through abnormalities of pigmentation in the iris. This technique is popular in many countries. Therefore it is relevant to ask whether it is valid. To systematically review all interpretable tests of the validity of iridology as a diagnostic tool. DATA SOURCE AND EXTRACTION: Three independent literature searches were performed to identify all blinded tests. Data were extracted in a predefined, standardized fashion. Four case control studies were found. The majority of these investigations suggests that iridology is not a valid diagnostic method. The validity of iridology as a diagnostic tool is not supported by scientific evaluations. Patients and therapists should be discouraged from using this method.
-
Messacar, Kevin; Breazeale, Garrett; Robinson, Christine C.; Dominguez, Samuel R.
2016-01-01
The FilmArray Meningitis Encephalitis Panel, a multiplex PCR for testing of cerebrospinal fluid, was compared to conventional diagnostic methods in children with suspected central nervous system infections. The panel had comparable diagnostic yield (96% agreement) and improved time-to-diagnosis by 10.3 hours with potential for more judicious antimicrobial use, particularly acyclovir. PMID:27342782
-
An Application of M[subscript 2] Statistic to Evaluate the Fit of Cognitive Diagnostic Models
ERIC Educational Resources Information Center
Liu, Yanlou; Tian, Wei; Xin, Tao
2016-01-01
The fit of cognitive diagnostic models (CDMs) to response data needs to be evaluated, since CDMs might yield misleading results when they do not fit the data well. Limited-information statistic M[subscript 2] and the associated root mean square error of approximation (RMSEA[subscript 2]) in item factor analysis were extended to evaluate the fit of…
-
Bowel lesions: percutaneous US-guided 18-gauge needle biopsy--preliminary experience.
Tudor, G R; Rodgers, P M; West, K P
1999-08-01
Ultrasonography-guided percutaneous biopsy was performed with local anesthesia and an 18-gauge needle in 10 patients with bowel-wall lesions. All patients underwent clinical review within 1 month. Biopsy was diagnostic in all patients. There were no complications, and all patients tolerated the procedure well. The technique appears to be safe and had an excellent diagnostic yield in our series.
-
A debate on the certainty of etiology in a case of syncope.
Dan, Anca Rodica; Daha, Ioana; Buzea, C A; Dan, G A
2013-01-01
We present the case of a 47-year-old woman with reccurent syncope. The investigations for establishing the etiology of syncope were extended over 4 years and multiple possible mecahisms for the syncope were identified. Even if the guidelines mention a good diagnostic yield for history and initial evaluation, for some selected cases the initial diagnostic supposition should be revised.
-
ERIC Educational Resources Information Center
Wahner, H. W.
1987-01-01
Early recognition of osteoporosis is difficult because symptoms are lacking and there are no distinct, readily accessible diagnostic features. This article reviews the standard approach, radiographic and laboratory diagnosis, bone mass measurement techniques, and interpretation of bone mineral data. (MT)
-
Energetic particle instabilities in fusion plasmas
NASA Astrophysics Data System (ADS)
Sharapov, S. E.; Alper, B.; Berk, H. L.; Borba, D. N.; Breizman, B. N.; Challis, C. D.; Classen, I. G. J.; Edlund, E. M.; Eriksson, J.; Fasoli, A.; Fredrickson, E. D.; Fu, G. Y.; Garcia-Munoz, M.; Gassner, T.; Ghantous, K.; Goloborodko, V.; Gorelenkov, N. N.; Gryaznevich, M. P.; Hacquin, S.; Heidbrink, W. W.; Hellesen, C.; Kiptily, V. G.; Kramer, G. J.; Lauber, P.; Lilley, M. K.; Lisak, M.; Nabais, F.; Nazikian, R.; Nyqvist, R.; Osakabe, M.; Perez von Thun, C.; Pinches, S. D.; Podesta, M.; Porkolab, M.; Shinohara, K.; Schoepf, K.; Todo, Y.; Toi, K.; Van Zeeland, M. A.; Voitsekhovich, I.; White, R. B.; Yavorskij, V.; TG, ITPA EP; Contributors, JET-EFDA
2013-10-01
Remarkable progress has been made in diagnosing energetic particle instabilities on present-day machines and in establishing a theoretical framework for describing them. This overview describes the much improved diagnostics of Alfvén instabilities and modelling tools developed world-wide, and discusses progress in interpreting the observed phenomena. A multi-machine comparison is presented giving information on the performance of both diagnostics and modelling tools for different plasma conditions outlining expectations for ITER based on our present knowledge.
-
Selberg, Kurt; Ross, Michael
2012-12-01
Nuclear scintigraphy is a mainstay of diagnostic imaging and has preserved its relevance in the imaging of acute and chronic trauma. It is particularly useful in the evaluation of athletic injuries. Pitfalls of interpretation, false negatives and false positives exist as with many imaging modalities. Synthesis of physical exam findings, lameness evaluation and, when possible, diagnostic analgesia in combination with nuclear scintigraphy imaging findings, will allow for the most information to be applied to the patient's clinical problem. Published by Elsevier Inc.
-
[Interpretation of false positive results of biochemical prenatal tests].
Sieroszewski, Piotr; Słowakiewicz, Katarzyna; Perenc, Małgorzata
2010-03-01
Modern, non-invasive prenatal diagnostics based on biochemical and ultrasonographic markers of fetal defects allows us to calculate the risk of fetal chromosomal aneuploidies with high sensitivity and specificity An introduction of biochemical, non-invasive prenatal tests turned out to result in frequent false positive results of these tests in cases when invasive diagnostics does not confirm fetal defects. However prospective analysis of these cases showed numerous complications in the third trimester of the pregnancies.
-
Definition of periprosthetic joint infection: is there a consensus?
Parvizi, Javad; Jacovides, Christina; Zmistowski, Benjamin; Jung, Kwang Am
2011-11-01
The diagnosis of periprosthetic joint infection (PJI) continues to pose a challenge. While many diagnostic criteria have been proposed, a gold standard for diagnosis is lacking. Use of multiple diagnostic criteria within the joint arthroplasty community raises concerns in patient treatment and comparison of research pertaining to PJI. We (1) determined the variation in existing diagnostic criteria, (2) compared the existing criteria to a proposed new set of criteria that incorporates aspirate cell count analysis, and (3) investigated the variations between the existing criteria and the proposed criteria. We retrospectively identified 182 patients undergoing 192 revision knee arthroplasties who had a preoperative joint aspiration analysis at our institution between April 2002 and November 2009. We excluded 20 cases due to insufficient laboratory parameters, leaving 172 cases for analysis. We applied six previously published sets of diagnostic criteria for PJI to determine the variation in its incidence using each set of criteria. We then compared these diagnostic criteria to our proposed new criteria and investigated cases where disagreement occurred. We identified 41 cases (24%) in which at least one established criteria set classified the case as infected while at least one other criteria set classified the case as uninfected. With our proposed criteria, the infected/uninfected ratio was 92/80. The proposed criteria had a large variance in sensitivity (54%-100%), specificity (39%-100%), and accuracy (53%-100%) when using each of the established criteria sets as the reference standard. The discrepancy between definitions of infection complicates interpretation of the literature and the treatment of failed TKAs owing to PJI. Based on our findings, we suggest establishing a common set of diagnostic criteria utilizing aspirate analysis to improve the treatment of PJI and facilitate interpretation of the literature. Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
-
Missed diagnostic opportunities within South Africa's early infant diagnosis program, 2010-2015.
Haeri Mazanderani, Ahmad; Moyo, Faith; Sherman, Gayle G
2017-01-01
Samples submitted for HIV PCR testing that fail to yield a positive or negative result represent missed diagnostic opportunities. We describe HIV PCR test rejections and indeterminate results, and the associated delay in diagnosis, within South Africa's early infant diagnosis (EID) program from 2010 to 2015. HIV PCR test data from January 2010 to December 2015 were extracted from the National Health Laboratory Service Corporate Data Warehouse, a central data repository of all registered test-sets within the public health sector in South Africa, by laboratory number, result, date, facility, and testing laboratory. Samples that failed to yield either a positive or negative result were categorized according to the rejection code on the laboratory information system, and descriptive analysis performed using Microsoft Excel. Delay in diagnosis was calculated for patients who had a missed diagnostic opportunity registered between January 2013 and December 2015 by means of a patient linking-algorithm employing demographic details. Between 2010 and 2015, 2 178 582 samples were registered for HIV PCR testing of which 6.2% (n = 134 339) failed to yield either a positive or negative result, decreasing proportionally from 7.0% (n = 20 556) in 2010 to 4.4% (n = 21 388) in 2015 (p<0.001). Amongst 76 972 coded missed diagnostic opportunities, 49 585 (64.4%) were a result of pre-analytical error and 27 387 (35.6%) analytical error. Amongst 49 694 patients searched for follow-up results, 16 895 (34.0%) had at least one subsequent HIV PCR test registered after a median of 29 days (IQR: 13-57), of which 8.4% tested positive compared with 3.6% of all samples submitted for the same period. Routine laboratory data provides the opportunity for near real-time surveillance and quality improvement within the EID program. Delay in diagnosis and wastage of resources associated with missed diagnostic opportunities must be addressed and infants actively followed-up as South Africa works towards elimination of mother-to-child transmission.
-
Armon-Lotem, Sharon; Meir, Natalia
2016-11-01
Previous research demonstrates that repetition tasks are valuable tools for diagnosing specific language impairment (SLI) in monolingual children in English and a variety of other languages, with non-word repetition (NWR) and sentence repetition (SRep) yielding high levels of sensitivity and specificity. Yet, only a few studies have addressed the diagnostic accuracy of repetition tasks in bilingual children, and most available research focuses on English-Spanish sequential bilinguals. To evaluate the efficacy of three repetition tasks (forward digit span (FWD), NWR and SRep) in order to distinguish mono- and bilingual children with and without SLI in Russian and Hebrew. A total of 230 mono- and bilingual children aged 5;5-6;8 participated in the study: 144 bilingual Russian-Hebrew-speaking children (27 with SLI); and 52 monolingual Hebrew-speaking children (14 with SLI) and 34 monolingual Russian-speaking children (14 with SLI). Parallel repetition tasks were designed in both Russian and Hebrew. Bilingual children were tested in both languages. The findings confirmed that NWR and SRep are valuable tools in distinguishing monolingual children with and without SLI in Russian and Hebrew, while the results for FWD were mixed. Yet, testing of bilingual children with the same tools using monolingual cut-off points resulted in inadequate diagnostic accuracy. We demonstrate, however, that the use of bilingual cut-off points yielded acceptable levels of diagnostic accuracy. The combination of SRep tasks in L1/Russian and L2/Hebrew yielded the highest overall accuracy (i.e., 94%), but even SRep alone in L2/Hebrew showed excellent levels of sensitivity (i.e., 100%) and specificity (i.e., 89%), reaching 91% of total diagnostic accuracy. The results are very promising for identifying SLI in bilingual children and for showing that testing in the majority language with bilingual cut-off points can provide an accurate classification. © 2016 Royal College of Speech and Language Therapists.
-
Determination of diagnostic standards on saturated soil extracts for cut roses grown in greenhouses
Cabrera, Raúl Iskander
2017-01-01
This work comprises the theoretical determination and validation of diagnostic standards for the analysis of saturated soil extracts for cut rose flower crops (Rosa spp.) growing in the Bogota Plateau, Colombia. The data included 684 plant tissue analyses and 684 corresponding analyses of saturated soil extracts, all collected between January 2009 and June 2013. The tissue and soil samples were selected from 13 rose farms, and from cultivars grafted on the 'Natal Briar' rootstock. These concurrent samples of soil and plant tissues represented 251 production units (locations) of approximately 10,000 m2 distributed across the study area. The standards were conceived as a tool to improve the nutritional balance in the leaf tissue of rose plants and thereby define the norms for expressing optimum productive potential relative to nutritional conditions in the soil. To this end, previously determined diagnostic standard for rose leaf tissues were employed to obtain rates of foliar nutritional balance at each analyzed location and as criteria for determining the diagnostic norms for saturated soil extracts. Implementing this methodology to foliar analysis, showed a higher significant correlation for diagnostic indices. A similar behavior was observed in saturated soil extracts analysis, becoming a powerful tool for integrated nutritional diagnosis. Leaf analyses determine the most limiting nutrients for high yield and analyses of saturated soil extracts facilitate the possibility of correcting the fertigation formulations applied to soils or substrates. Recommendations are proposed to improve the balance in soil-plant system with which the possibility of yield increase becomes more probable. The main recommendations to increase and improve rose crop flower yields would be: continuously check pH values of SSE, reduce the amounts of P, Fe, Zn and Cu in fertigation solutions and carefully analyze the situation of Mn in the soil-plant system. PMID:28542547
-
Interpretation of bedside chest X-rays in the ICU: is the radiologist still needed?
Martini, Katharina; Ganter, Christoph; Maggiorini, Marco; Winklehner, Anna; Leupi-Skibinski, Katarzyna E; Frauenfelder, Thomas; Nguyen-Kim, Thi Dan Linh
2015-01-01
To compare diagnostic accuracy of intensivists to radiologists in reading bedside chest X-rays. In a retrospective trial, 33 bedside chest X-rays were evaluated by five radiologists and five intensivists with different experience. Images were evaluated for devices and lung pathologies. Interobserver agreement and diagnostic accuracy were calculated. Computed tomography served as reference standard. Seniors had higher diagnostic accuracy than residents (mean-ExpB(Senior)=1.456; mean-ExpB(Resident)=1.635). Interobserver agreement for installations was more homogenously distributed between radiologists compared to intensivists (ExpB(Rad)=1.204-1.672; ExpB(Int)=1.005-2.368). Seniors had comparable diagnostic accuracy. No significant difference in diagnostic performance was seen between seniors of both disciplines, whereas the resident intensivists might still benefit from an interdisciplinary dialogue. Copyright © 2015 Elsevier Inc. All rights reserved.
-
Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Y., E-mail: yhkim@lanl.gov; Herrmann, H. W.; Jorgenson, H. J.
2014-11-15
The Gamma-to-Electron Magnetic Spectrometer (GEMS) diagnostic is designed to measure the prompt γ-ray energy spectrum during high yield deuterium-tritium (DT) implosions at the National Ignition Facility (NIF). The prompt γ-ray spectrum will provide “burn-averaged” observables, including total DT fusion yield, total areal density (ρR), ablator ρR, and fuel ρR. These burn-averaged observables are unique because they are essentially averaged over 4π, providing a global reference for the line-of-sight-specific measurements typical of x-ray and neutron diagnostics. The GEMS conceptual design meets the physics-based requirements: ΔE/E = 3%–5% can be achieved in the range of 2–25 MeV γ-ray energy. Minimum DT neutronmore » yields required for 15% measurement uncertainty at low-resolution mode are: 5 × 10{sup 14} DT-n for ablator ρR (at 0.2 g/cm{sup 2}); 2 × 10{sup 15} DT-n for total DT yield (at 4.2 × 10{sup −5} γ/n); and 1 × 10{sup 16} DT-n for fuel ρR (at 1 g/cm{sup 2})« less
-
Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility
Kim, Y.; Herrmann, H. W.; Jorgenson, H. J.; ...
2014-08-01
The Gamma-to-Electron Magnetic Spectrometer (GEMS) diagnostic is designed to measure the prompt γ-ray energy spectrum during high yield deuterium-tritium (DT) implosions at the National Ignition Facility (NIF). The prompt γ-ray spectrum will provide ‘burn-averaged’ observables, including total DT fusion yield, total areal density (ρR), ablator ρR, and fuel ρR. These burn-averaged observables are unique because they are essentially averaged over 4π, providing a global reference for the line-of-sight-specific measurements typical of x-ray and neutron diagnostics. The GEMS conceptual design meets the physics-based requirements: ΔE/E = 3 - 5% can be achieved in the range of 2 - 25 MeV γ-raymore » energy. Minimum DT neutron yields required for 15% measurement uncertainty at low-resolution mode are: 5×10 14 DT-n for ablator ρR (at 0.2 g/cm 2); 2×10 15 DT-n for total DT yield (at 4.2×10 -5γ /n); and 1×10 16 DT-n for fuel ρR (at 1 g/cm 2).« less
-
Early-Onset Neonatal Sepsis: Still Room for Improvement in Procalcitonin Diagnostic Accuracy Studies
Chiesa, Claudio; Pacifico, Lucia; Osborn, John F.; Bonci, Enea; Hofer, Nora; Resch, Bernhard
2015-01-01
Abstract To perform a systematic review assessing accuracy and completeness of diagnostic studies of procalcitonin (PCT) for early-onset neonatal sepsis (EONS) using the Standards for Reporting of Diagnostic Accuracy (STARD) initiative. EONS, diagnosed during the first 3 days of life, remains a common and serious problem. Increased PCT is a potentially useful diagnostic marker of EONS, but reports in the literature are contradictory. There are several possible explanations for the divergent results including the quality of studies reporting the clinical usefulness of PCT in ruling in or ruling out EONS. We systematically reviewed PubMed, Scopus, and the Cochrane Library databases up to October 1, 2014. Studies were eligible for inclusion in our review if they provided measures of PCT accuracy for diagnosing EONS. A data extraction form based on the STARD checklist and adapted for neonates with EONS was used to appraise the quality of the reporting of included studies. We found 18 articles (1998–2014) fulfilling our eligibility criteria which were included in the final analysis. Overall, the results of our analysis showed that the quality of studies reporting diagnostic accuracy of PCT for EONS was suboptimal leaving ample room for improvement. Information on key elements of design, analysis, and interpretation of test accuracy were frequently missing. Authors should be aware of the STARD criteria before starting a study in this field. We welcome stricter adherence to this guideline. Well-reported studies with appropriate designs will provide more reliable information to guide decisions on the use and interpretations of PCT test results in the management of neonates with EONS. PMID:26222858
-
Samples, Laura S; Rendi, Mara H; Frederick, Paul D; Allison, Kimberly H; Nelson, Heidi D; Morgan, Thomas R; Weaver, Donald L; Elmore, Joann G
2017-08-01
Flat epithelial atypia (FEA) is a relatively new diagnostic term with uncertain clinical significance for surgical management. Any implied risk of invasive breast cancer associated with FEA is contingent upon diagnostic reproducibility, yet little is known regarding its use. Pathologists in the Breast Pathology Study interpreted one of four 60-case test sets, one slide per case, constructed from 240 breast biopsy specimens. An electronic data form with standardized diagnostic categories was used; participants were instructed to indicate all diagnoses present. We assessed participants' use of FEA as a diagnostic term within: 1) each test set; 2) 72 cases classified by reference as benign without FEA; and 3) six cases classified by reference as FEA. 115 pathologists participated, providing 6900 total independent assessments. Notation of FEA ranged from 0% to 35% of the cases interpreted, with most pathologists noting FEA on 4 or more test cases. At least one participant noted FEA in 34 of the 72 benign non-FEA cases. For the 6 reference FEA cases, participant agreement with the case reference FEA diagnosis ranged from 17% to 52%; diagnoses noted by participating pathologists for these FEA cases included columnar cell hyperplasia, usual ductal hyperplasia, atypical lobular hyperplasia, and atypical ductal hyperplasia. We observed wide variation in the diagnosis of FEA among U.S. pathologists. This suggests that perceptions of diagnostic criteria and any implied risk associated with FEA may also vary. Surgical excision following a core biopsy diagnosis of FEA should be reconsidered and studied further. Copyright © 2017 Elsevier Ltd. All rights reserved.
-
Bonert, Michael; El-Shinnawy, Ihab; Carvalho, Michael; Williams, Phillip; Salama, Samih; Tang, Damu; Kapoor, Anil
2017-01-01
Observational data and funnel plots are routinely used outside of pathology to understand trends and improve performance. Extract diagnostic rate (DR) information from free text surgical pathology reports with synoptic elements and assess whether inter-rater variation and clinical history completeness information useful for continuous quality improvement (CQI) can be obtained. All in-house prostate biopsies in a 6-year period at two large teaching hospitals were extracted and then diagnostically categorized using string matching, fuzzy string matching, and hierarchical pruning. DRs were then stratified by the submitting physicians and pathologists. Funnel plots were created to assess for diagnostic bias. 3,854 prostate biopsies were found and all could be diagnostically classified. Two audits involving the review of 700 reports and a comparison of the synoptic elements with the free text interpretations suggest a categorization error rate of <1%. Twenty-seven pathologists each read >40 cases and together assessed 3,690 biopsies. There was considerable inter-rater variability and a trend toward more World Health Organization/International Society of Urologic Pathology Grade 1 cancers in older pathologists. Normalized deviations plots, constructed using the median DR, and standard error can elucidate associated over- and under-calls for an individual pathologist in relation to their practice group. Clinical history completeness by submitting medical doctor varied significantly (100% to 22%). Free text data analyses have some limitations; however, they could be used for data-driven CQI in anatomical pathology, and could lead to the next generation in quality of care.
-
Westphal, Saskia E; Apitzsch, Jonas C; Penzkofer, Tobias; Kuhl, Christiane K; Mahnken, Andreas H; Knüchel, Ruth
2014-09-01
Postmortem computed tomography (PMCT) is a modern tool that complements autopsy diagnostics. In clinical autopsies, a major cause of death is cardiovascular disease. To improve the performance of PMCT in cardiovascular disease, full body angiography was developed (PMCT angiography [PMCTA]). Twenty PMCTA scans generated before autopsy were compared with native PMCT and clinical autopsy. The objective of the study was to quantify the additional diagnostic value of adding angiography to native imaging and to compare PMCT and PMCTA findings to autopsy findings. The diagnosis of the cause of death was identical or overlapped in 80% of the cases that used PMCTA and 70% that used PMCT. The additional diagnostic yield given by PMCT and PMCTA in combination with autopsy was 55%. PMCT yielded additional diagnoses in the musculoskeletal system. The greatest additional diagnostic value of PMCTA was in association with cardiovascular diagnoses. The accuracy of PMCTA for cardiac causes of death was 80%, and the positive predictive value was 90%. The findings indicate that native PMCT cannot display the cardiovascular system sufficiently clearly for high-quality diagnostic assessment. However, PMCTA is a powerful tool in autopsy cases with a history of cardiovascular disease and/or a suspected cardiovascular cause of death. The combination of PMCTA and clinical autopsy enhances diagnostic quality and completeness of the autopsy report. Furthermore, in cases without consent or with a restricted consent for clinical autopsy, PMCTA has the potential to provide information on cardiovascular causes of death. Copyright © 2014 Elsevier Inc. All rights reserved.
-
Koegelenberg, Coenraad Frederik N; Bolliger, Christoph Thomas; Theron, Johan; Walzl, Gerhard; Wright, Colleen Anne; Louw, Mercia; Diacon, Andreas Henri
2010-10-01
Tuberculous pleuritis remains the commonest cause of exudative effusions in areas with a high prevalence of tuberculosis and histological and/or microbiological confirmation on pleural tissue is the gold standard for its diagnosis. Uncertainty remains regarding the choice of closed pleural biopsy needles. This prospective study compared ultrasound-assisted Abrams and Tru-Cut needle biopsies with regard to their diagnostic yield for pleural tuberculosis. 89 patients (54 men) of mean ± SD age 38.7 ± 16.7 years with pleural effusions and a clinical suspicion of tuberculosis were enrolled in the study. Transthoracic ultrasound was performed on all patients, who were then randomly assigned to undergo ≥ 4 Abrams needle biopsies followed by ≥ 4 Tru-Cut needle biopsies or vice versa. Medical thoracoscopy was performed on cases with non-diagnostic closed biopsies. Histological and/or microbiological proof of tuberculosis on any pleural specimen was considered the gold standard for pleural tuberculosis. Pleural tuberculosis was diagnosed in 66 patients, alternative diagnoses were established in 20 patients and 3 remained undiagnosed. Pleural biopsy specimens obtained with Abrams needles contained pleural tissue in 81 patients (91.0%) and were diagnostic for tuberculosis in 54 patients (sensitivity 81.8%), whereas Tru-Cut needle biopsy specimens only contained pleural tissue in 70 patients (78.7%, p=0.015) and were diagnostic in 43 patients (sensitivity 65.2%, p=0.022). Ultrasound-assisted pleural biopsies performed with an Abrams needle are more likely to contain pleura and have a significantly higher diagnostic sensitivity for pleural tuberculosis.
-
Toxoplasma gondii: history and diagnostic test development.
Wyrosdick, Heidi M; Schaefer, John J
2015-12-01
Toxoplasma gondii is a protozoa that causes toxoplasmosis in people and other animals. It is considered one of the most common parasitic infections in the world due to its impressive range of hosts, widespread environmental contamination and the diverse means by which animals can be infected. Despite its ubiquity and numerous ongoing research efforts into both its basic biology and clinical management, many aspects of diagnosis and management of this disease are poorly understood. The range of diagnostic options that is available for veterinary diagnostic investigators are notably more limited than those available to medical diagnosticians, making accurate interpretation of each test result critical. The current review joins other reviews on the parasite with a particular emphasis on the history and continued development of diagnostic tests that are useful for veterinary diagnostic investigations. An understanding of the strengths and shortcomings of current diagnostic techniques will assist veterinary and public health officials in formulating effective treatment and control strategies in diverse animal populations.
-
Model of critical diagnostic reasoning: achieving expert clinician performance.
Harjai, Prashant Kumar; Tiwari, Ruby
2009-01-01
Diagnostic reasoning refers to the analytical processes used to determine patient health problems. While the education curriculum and health care system focus on training nurse clinicians to accurately recognize and rescue clinical situations, assessments of non-expert nurses have yielded less than satisfactory data on diagnostic competency. The contrast between the expert and non-expert nurse clinician raises the important question of how differences in thinking may contribute to a large divergence in accurate diagnostic reasoning. This article recognizes superior organization of one's knowledge base, using prototypes, and quick retrieval of pertinent information, using similarity recognition as two reasons for the expert's superior diagnostic performance. A model of critical diagnostic reasoning, using prototypes and similarity recognition, is proposed and elucidated using case studies. This model serves as a starting point toward bridging the gap between clinical data and accurate problem identification, verification, and management while providing a structure for a knowledge exchange between expert and non-expert clinicians.
-
ERIC Educational Resources Information Center
Maydeu-Olivares, Alberto; Hernandez, Adolfo
2007-01-01
The interpretation of a Thurstonian model for paired comparisons where the utilities' covariance matrix is unrestricted proved to be difficult due to the comparative nature of the data. We show that under a suitable constraint the utilities' correlation matrix can be estimated, yielding a readily interpretable solution. This set of identification…
-
Screening for ketosis using multiple logistic regression based on milk yield and composition.
Kayano, Mitsunori; Kataoka, Tomoko
2015-11-01
Multiple logistic regression was applied to milk yield and composition data for 632 records of healthy cows and 61 records of ketotic cows in Hokkaido, Japan. The purpose was to diagnose ketosis based on milk yield and composition, simultaneously. The cows were divided into two groups: (1) multiparous, including 314 healthy cows and 45 ketotic cows and (2) primiparous, including 318 healthy cows and 16 ketotic cows, since nutritional status, milk yield and composition are affected by parity. Multiple logistic regression was applied to these groups separately. For multiparous cows, milk yield (kg/day/cow) and protein-to-fat (P/F) ratio in milk were significant factors (P<0.05) for the diagnosis of ketosis. For primiparous cows, lactose content (%), solid not fat (SNF) content (%) and milk urea nitrogen (MUN) content (mg/dl) were significantly associated with ketosis (P<0.01). A diagnostic rule was constructed for each group of cows: (1) 9.978 × P/F ratio + 0.085 × milk yield <10 and (2) 2.327 × SNF - 2.703 × lactose + 0.225 × MUN <10. The sensitivity, specificity and the area under the curve (AUC) of the diagnostic rules were (1) 0.800, 0.729 and 0.811; (2) 0.813, 0.730 and 0.787, respectively. The P/F ratio, which is a widely used measure of ketosis, provided the sensitivity, specificity and AUC values of (1) 0.711, 0.726 and 0.781; and (2) 0.678, 0.767 and 0.738, respectively.
-
Wang, Sa A.; Pozdnyakova, Olga; Jorgensen, Jeffrey L.; Medeiros, L. Jeffrey; Stachurski, Dariusz; Anderson, Mary; Raza, Azra; Woda, Bruce A.
2009-01-01
Background The presence of paroxysmal nocturnal hemoglobinuria clones in the setting of aplastic anemia or myelodysplastic syndrome has been shown to have prognostic and therapeutic implications. However, the status of paroxysmal nocturnal hemoglobinuria clones in various categories of myelodysplastic syndrome and in other bone marrow disorders is not well-studied. Design and Methods By using multiparameter flow cytometry immunophenotypic analysis with antibodies specific for four glycosylphosphatidylinositol-anchored proteins (CD55, CD59, CD16, CD66b) and performing an aerolysin lysis confirmatory test in representative cases, we assessed the paroxysmal nocturnal hemoglobinuria-phenotype granulocytes in 110 patients with myelodysplastic syndrome, 15 with myelodysplastic/myeloproliferative disease, 5 with idiopathic myelofibrosis and 6 with acute myeloid leukemia. Results Paroxysmal nocturnal hemoglobinuria-phenotype granulocytes were detected in nine patients with low grade myelodysplastic syndrome who showed clinicopathological features of bone marrow failure, similar to aplastic anemia. All paroxysmal nocturnal hemoglobinuria-positive cases demonstrated loss of the four glycosylphosphatidylinositol-anchored proteins, with CD16−CD66b− clones being larger than those of CD55−CD59− (p<0.05). Altered glycosylphosphatidylinositol-anchored protein expression secondary to granulocytic hypogranulation, immaturity, and/or immunophenotypic abnormalities was present in a substantial number of cases and diagnostically challenging. Conclusions These results show that routine screening for paroxysmal nocturnal hemoglobinuria clones in patients with an intrinsic bone marrow disease who show no clinical evidence of hemolysis has an appreciable yield in patients with low grade myelodysplastic syndromes. The recognition of diagnostic caveats and pitfalls associated with the underlying intrinsic bone marrow disease is essential in interpreting paroxysmal nocturnal hemoglobinuria testing correctly. In our experience, the CD16/CD66b antibody combination is superior to CD55/CD59 in screening for subclinical paroxysmal nocturnal hemoglobinuria because it detects a large clone size and is less subject to analytical interference. PMID:19001281
-
Wang, Sa A; Pozdnyakova, Olga; Jorgensen, Jeffrey L; Medeiros, L Jeffrey; Stachurski, Dariusz; Anderson, Mary; Raza, Azra; Woda, Bruce A
2009-01-01
The presence of paroxysmal nocturnal hemoglobinuria clones in the setting of aplastic anemia or myelodysplastic syndrome has been shown to have prognostic and therapeutic implications. However, the status of paroxysmal nocturnal hemoglobinuria clones in various categories of myelodysplastic syndrome and in other bone marrow disorders is not well-studied. By using multiparameter flow cytometry immunophenotypic analysis with antibodies specific for four glycosylphosphatidylinositol-anchored proteins (CD55, CD59, CD16, CD66b) and performing an aerolysin lysis confirmatory test in representative cases, we assessed the paroxysmal nocturnal hemoglobinuria-phenotype granulocytes in 110 patients with myelodysplastic syndrome, 15 with myelodysplastic/myeloproliferative disease, 5 with idiopathic myelofibrosis and 6 with acute myeloid leukemia. Paroxysmal nocturnal hemoglobinuria-phenotype granulocytes were detected in nine patients with low grade myelodysplastic syndrome who showed clinicopathological features of bone marrow failure, similar to aplastic anemia. All paroxysmal nocturnal hemoglobinuria-positive cases demonstrated loss of the four glycosylphosphatidylinositol-anchored proteins, with CD16(-)CD66b(-) clones being larger than those of CD55(-)CD59(-) (p<0.05). Altered glycosylphosphatidylinositol-anchored protein expression secondary to granulocytic hypogranulation, immaturity, and/or immunophenotypic abnormalities was present in a substantial number of cases and diagnostically challenging. These results show that routine screening for paroxysmal nocturnal hemoglobinuria clones in patients with an intrinsic bone marrow disease who show no clinical evidence of hemolysis has an appreciable yield in patients with low grade myelodysplastic syndromes. The recognition of diagnostic caveats and pitfalls associated with the underlying intrinsic bone marrow disease is essential in interpreting paroxysmal nocturnal hemoglobinuria testing correctly. In our experience, the CD16/CD66b antibody combination is superior to CD55/CD59 in screening for subclinical paroxysmal nocturnal hemoglobinuria because it detects a large clone size and is less subject to analytical interference.
-
Neumann, Thomas; Baum, Anne Katrin; Baum, Ulrike; Deike, Renate; Feistner, Helmut; Hinrichs, Hermann; Stokes, Joseph; Robra, Bernt-Peter
2018-01-01
The HOME ONE study is part of the larger HOME project, which aims to provide evidence of diagnostic and therapeutic yield ("change of management") of a patient-controlled portable EEG device with dry electrodes for the purposes of EEG home-monitoring neurological outpatients. The HOME ONE study is the first step in the process of investigating whether outpatient EEG home-monitoring changes the diagnosis and treatment of patients in comparison to conventional EEG ("change of management"). Both EEG devices (conventional and portable) will be systematically compared via a two-phase intra-individual assessment.In the first phase (pilot study phase), both EEG devices will be used within neurologist practices (all other things being equal). This pilot study (involving 130 patients) will evaluate the technical usability and efficacy of the new portable dry electrode EEG recorder in comparison to conventional EEG devices. Judgements will be based on technical assessments and EEG record examinations of private practitioners and two experienced neurologists (percent of concordant readings and kappa values).The second phase (feasibility study phase) aims to assess patients' acceptability and feasibility of the EEG home-monitoring and will provide insights into the extent diagnostic and therapeutic yields can be expected.For this purpose, a conventional EEG will be recorded in neurologist practices. Thereafter, the practice staff will instruct the patients on how the portable EEG device functions. The patients will subsequently use the devices in their home environment.The evaluation will compare the before and after documented diagnostic findings and the therapeutic consequences of the private practitioners with those of two experienced neurologists. To the best of our knowledge, this will be the first study of its kind to examine new approaches to diagnosing unclear consciousness disorders or other disorders of the CNS or the cardiovascular system through the use of a patient-controlled portable EEG device with dry electrodes for the purpose of home-monitoring neurological outpatients. If the two phases of the HOME ONE study provide sufficient evidence of diagnostic and therapeutic yields, this would justify (indication-specific) full-scale randomized controlled trials or observational studies. DRKS DRKS00012685. Registered 9 August 2017, retrospectively registered.
-
Clements, Michelle N; Corstjens, Paul L A M; Binder, Sue; Campbell, Carl H; de Dood, Claudia J; Fenwick, Alan; Harrison, Wendy; Kayugi, Donatien; King, Charles H; Kornelis, Dieuwke; Ndayishimiye, Onesime; Ortu, Giuseppina; Lamine, Mariama Sani; Zivieri, Antonio; Colley, Daniel G; van Dam, Govert J
2018-02-23
Kato-Katz examination of stool smears is the field-standard method for detecting Schistosoma mansoni infection. However, Kato-Katz misses many active infections, especially of light intensity. Point-of-care circulating cathodic antigen (CCA) is an alternative field diagnostic that is more sensitive than Kato-Katz when intensity is low, but interpretation of CCA-trace results is unclear. To evaluate trace results, we tested urine and stool specimens from 398 pupils from eight schools in Burundi using four approaches: two in Burundi and two in a laboratory in Leiden, the Netherlands. In Burundi, we used Kato-Katz and point-of-care CCA (CCAB). In Leiden, we repeated the CCA (CCAL) and also used Up-Converting Phosphor Circulating Anodic Antigen (CAA). We applied Bayesian latent class analyses (LCA), first considering CCA traces as negative and then as positive. We used the LCA output to estimate validity of the prevalence estimates of each test in comparison to the population-level infection prevalence and estimated the proportion of trace results that were likely true positives. Kato-Katz yielded the lowest prevalence (6.8%), and CCAB with trace considered positive yielded the highest (53.5%). There were many more trace results recorded by CCA in Burundi (32.4%) than in Leiden (2.3%). Estimated prevalence with CAA was 46.5%. LCA indicated that Kato-Katz had the lowest sensitivity: 15.9% [Bayesian Credible Interval (BCI): 9.2-23.5%] with CCA-trace considered negative and 15.0% with trace as positive (BCI: 9.6-21.4%), implying that Kato-Katz missed approximately 85% of infections. CCAB underestimated disease prevalence when trace was considered negative and overestimated disease prevalence when trace was considered positive, by approximately 12 percentage points each way, and CAA overestimated prevalence in both models. Our results suggest that approximately 52.2% (BCI: 37.8-5.8%) of the CCAB trace readings were true infections. Whether measured in the laboratory or the field, CCA outperformed Kato-Katz at the low infection intensities in Burundi. CCA with trace as negative likely missed many infections, whereas CCA with trace as positive overestimated prevalence. In the absence of a field-friendly gold standard diagnostic, the use of a variety of diagnostics with differing properties will become increasingly important as programs move towards elimination of schistosomiasis. It is clear that CCA is a valuable tool for the detection and mapping of S. mansoni infection in the field and CAA may be a valuable field tool in the future.
-
NASA Astrophysics Data System (ADS)
Dias-da-Silva, Sérgio; Pinheiro, Felipe L.; Stock Da-Rosa, Átila Augusto; Martinelli, Agustín G.; Schultz, Cesar L.; Silva-Neves, Eduardo; Modesto, Sean P.
2017-11-01
The Sanga do Cabral Supersequence (SCS), comprises the Brazilian Sanga do Cabral Formation (SCF) and the Uruguayan Buena Vista Formation (BVF). So far, the SCS has yielded temnospondyls, parareptiles, archosauromorphs, putative synapsids, and a number of indeterminate specimens. In the absence of absolute dates for these rocks, a biostratigraphic approach is necessary to establish the ages of the SCF and the BVF. It is well established that the SCF is Early Triassic mainly due to the presence of the widespread Gondwanan reptile Procolophon trigoniceps. Conversely, the age of the BVF is subject of great controversy, being regarded alternatively as Permian, Permo-Triassic, and Early Triassic. The BVF has yielded the definite procolophonid Pintosaurus magnidentis. Procolophonoidea is one of the most diverse and conspicuous terrestrial tetrapod groups of the Lower Triassic Lystrosaurus Assemblage Zone in the Karoo Basin of South Africa, which preserves tetrapods from the aftermath of the end-Permian extinction event. Based on a previous interpretation that the fauna of the BVF is Permian, and in the reinterpretation of disarticulated vertebrae from SCF with 'swollen' neural arches as belonging to either seymouriamorphs or diadectomorphs, it was recently suggested that at least part of the SCF is Permian in age, which prompted this comprehensive reevaluation of both SCS's faunal content and geology. Moreoever, new, strikingly large procolophonid specimens (skull, vertebra, and a mandibular fragment) from the SCF are described and referred to the genus Procolophon. The large procolophonid vertebra described here contradicts the recent hypothesis that similar specimens from the SCF belong to seymouriamorphs or diadectomorphs, because its morphology is consistent with that found in Procolophon. There is not a single diagnostic specimen that supports the inference of Permian levels in the SCS. Accordingly, because all diagnostic and biostratigraphically informative fossils from the SCF and the BVF are either Early Triassic or restricted to the Triassic, we conclude that the available biostratigraphic data reinforce an Early Triassic age assignment to the SCS.
-
Biopsy of CT-Occult Bone Lesions Using Anatomic Landmarks for CT Guidance.
Hillen, Travis J; Talbert, Robert J; Friedman, Michael V; Long, Jeremiah R; Jennings, Jack W; Wessell, Daniel E; Baker, Jonathan C
2017-07-01
The purpose of this study is to evaluate the histopathologic diagnostic yield, sample size, procedural time, and dose-length product (DLP) for the biopsy of CT-occult lesions found at MRI or PET or both. A retrospective review of our radiology information system for biopsies of CT-occult lesions using CT guidance from January 1, 2010, through December 31, 2014, was performed and compared with a selection of CT-guided biopsies of CT-evident bone lesions during the same period. The data were then evaluated for diagnostic yield of histopathologic diagnosis, procedural time, use of sedation medication, DLP, and size of specimens obtained. A total of 30 CT-occult biopsies met the inclusion criteria. Twenty-seven of those biopsies had results that were concordant with the patient's primary histopathologic diagnosis, imaging findings, and clinical course. In the CT-evident lesion group, concordant histopathologic abnormalities were identified in 27 of 30 patients. There was a statistically significant increase in number of samples obtained for the CT-evident lesions compared with CT-occult lesions. There was no statistically significant difference in total specimen length, DLP, number of CT scans, procedural time, or use of sedation medication between the CT-occult and CT-evident biopsy groups. Biopsy of CT-occult lesions using anatomic landmarks achieves diagnostic yields similar to those for CT-guided biopsy of CT-evident lesions.
-
Descendants of the first stars: the distinct chemical signature of second generation stars
NASA Astrophysics Data System (ADS)
Hartwig, Tilman; Yoshida, Naoki; Magg, Mattis; Frebel, Anna; Glover, Simon C. O.; Gómez, Facundo A.; Griffen, Brendan; Ishigaki, Miho N.; Ji, Alexander P.; Klessen, Ralf S.; O'Shea, Brian W.; Tominaga, Nozomu
2018-05-01
Extremely metal-poor (EMP) stars in the Milky Way (MW) allow us to infer the properties of their progenitors by comparing their chemical composition to the metal yields of the first supernovae. This method is most powerful when applied to mono-enriched stars, i.e. stars that formed from gas that was enriched by only one previous supernova. We present a novel diagnostic to identify this subclass of EMP stars. We model the first generations of star formation semi-analytically, based on dark matter halo merger trees that yield MW-like halos at the present day. Radiative and chemical feedback are included self-consistently and we trace all elements up to zinc. Mono-enriched stars account for only ˜1% of second generation stars in our fiducial model and we provide an analytical formula for this probability. We also present a novel analytical diagnostic to identify mono-enriched stars, based on the metal yields of the first supernovae. This new diagnostic allows us to derive our main results independently from the specific assumptions made regarding Pop III star formation, and we apply it to a set of observed EMP stars to demonstrate its strengths and limitations. Our results may provide selection criteria for current and future surveys and therefore contribute to a deeper understanding of EMP stars and their progenitors.
-
Shivakumarswamy, Udasimath; Arakeri, Surekha U; Karigowdar, Mahesh H; Yelikar, Br
2012-01-01
The cytological examinations of serous effusions have been well-accepted, and a positive diagnosis is often considered as a definitive diagnosis. It helps in staging, prognosis and management of the patients in malignancies and also gives information about various inflammatory and non-inflammatory lesions. Diagnostic problems arise in everyday practice to differentiate reactive atypical mesothelial cells and malignant cells by the routine conventional smear (CS) method. To compare the morphological features of the CS method with those of the cell block (CB) method and also to assess the utility and sensitivity of the CB method in the cytodiagnosis of pleural effusions. The study was conducted in the cytology section of the Department of Pathology. Sixty pleural fluid samples were subjected to diagnostic evaluation for over a period of 20 months. Along with the conventional smears, cell blocks were prepared by using 10% alcohol-formalin as a fixative agent. Statistical analysis with the 'z test' was performed to identify the cellularity, using the CS and CB methods. Mc. Naemer's χ(2)test was used to identify the additional yield for malignancy by the CB method. Cellularity and additional yield for malignancy was 15% more by the CB method. The CB method provides high cellularity, better architectural patterns, morphological features and an additional yield of malignant cells, and thereby, increases the sensitivity of the cytodiagnosis when compared with the CS method.
-
Sanfilippo, Paul G; Hewitt, Alex W; Mackey, David A
2017-04-01
To outline and detail the importance of conditional probability in clinical decision making and discuss the various diagnostic measures eye care practitioners should be aware of in order to improve the scope of their clinical practice. We conducted a review of the importance of conditional probability in diagnostic testing for the eye care practitioner. Eye care practitioners use diagnostic tests on a daily basis to assist in clinical decision making and optimizing patient care and management. These tests provide probabilistic information that can enable the clinician to increase (or decrease) their level of certainty about the presence of a particular condition. While an understanding of the characteristics of diagnostic tests are essential to facilitate proper interpretation of test results and disease risk, many practitioners either confuse or misinterpret these measures. In the interests of their patients, practitioners should be aware of the basic concepts associated with diagnostic testing and the simple mathematical rule that underpins them. Importantly, the practitioner needs to recognize that the prevalence of a disease in the population greatly determines the clinical value of a diagnostic test.
-
Cox, Linda; Williams, Brock; Sicherer, Scott; Oppenheimer, John; Sher, Larry; Hamilton, Robert; Golden, David
2008-12-01
The intended purpose of this monograph is to provide a general overview of allergy diagnostics for health care professionals who care for patients with allergic disease. For a more comprehensive review of allergy diagnostic testing, readers can refer to the Allergy Diagnostic Practice Parameters. A key message is that a positive allergy test result (skin or blood) indicates only the presence of allergen specific IgE (called sensitization). It does not necessarily mean clinical allergy (ie, allergic symptoms with exposure). It is important for this reason that the allergy evaluation be based on the patient's history and directed by a health care professional with sufficient understanding of allergy diagnostic testing to use the information obtained from his/her evaluation of the patient to determine (1) what allergy diagnostic tests to order, (2) how to interpret the allergy diagnostic test results, and (3) how to use the information obtained from the allergy evaluation to develop an appropriate therapeutic treatment plan.
-
Effects of using the developing nurses' thinking model on nursing students' diagnostic accuracy.
Tesoro, Mary Gay
2012-08-01
This quasi-experimental study tested the effectiveness of an educational model, Developing Nurses' Thinking (DNT), on nursing students' clinical reasoning to achieve patient safety. Teaching nursing students to develop effective thinking habits that promote positive patient outcomes and patient safety is a challenging endeavor. Positive patient outcomes and safety are achieved when nurses accurately interpret data and subsequently implement appropriate plans of care. This study's pretest-posttest design determined whether use of the DNT model during 2 weeks of clinical postconferences improved nursing students' (N = 83) diagnostic accuracy. The DNT model helps students to integrate four constructs-patient safety, domain knowledge, critical thinking processes, and repeated practice-to guide their thinking when interpreting patient data and developing effective plans of care. The posttest scores of students from the intervention group showed statistically significant improvement in accuracy. Copyright 2012, SLACK Incorporated.
-
Moore, Andrew; Nelson, Christina; Molins, Claudia; Mead, Paul; Schriefer, Martin
2016-07-01
In the United States, Lyme disease is caused by Borrelia burgdorferi and transmitted to humans by blacklegged ticks. Patients with an erythema migrans lesion and epidemiologic risk can receive a diagnosis without laboratory testing. For all other patients, laboratory testing is necessary to confirm the diagnosis, but proper interpretation depends on symptoms and timing of illness. The recommended laboratory test in the United States is 2-tiered serologic analysis consisting of an enzyme-linked immunoassay or immunofluorescence assay, followed by reflexive immunoblotting. Sensitivity of 2-tiered testing is low (30%-40%) during early infection while the antibody response is developing (window period). For disseminated Lyme disease, sensitivity is 70%-100%. Specificity is high (>95%) during all stages of disease. Use of other diagnostic tests for Lyme disease is limited. We review the rationale behind current US testing guidelines, appropriate use and interpretation of tests, and recent developments in Lyme disease diagnostics.
-
Hepatocellular carcinoma: Advances in diagnostic imaging.
Sun, Haoran; Song, Tianqiang
2015-10-01
Thanks to the growing knowledge on biological behaviors of hepatocellular carcinomas (HCC), as well as continuous improvement in imaging techniques and experienced interpretation of imaging features of the nodules in cirrhotic liver, the detection and characterization of HCC has improved in the past decade. A number of practice guidelines for imaging diagnosis have been developed to reduce interpretation variability and standardize management of HCC, and they are constantly updated with advances in imaging techniques and evidence based data from clinical series. In this article, we strive to review the imaging techniques and the characteristic features of hepatocellular carcinoma associated with cirrhotic liver, with emphasis on the diagnostic value of advanced magnetic resonance imaging (MRI) techniques and utilization of hepatocyte-specific MRI contrast agents. We also briefly describe the concept of liver imaging reporting and data systems and discuss the consensus and controversy of major practice guidelines.
-
Recent Changes of Classification for Squamous Intraepithelial Lesions of the Head and Neck.
Cho, Kyung-Ja; Song, Joon Seon
2018-05-18
- Interpretation of atypical squamous lesions of the head and neck has always been a nettlesome task for pathologists. Moreover, many different grading systems for squamous intraepithelial lesions have been proposed in past decades. The recent World Health Organization 2017 classification presents 2 types of 2-tier systems for laryngeal and oral precursor lesions. - To review the recent changes in classification and the clinical significance for squamous intraepithelial lesions of the head and neck. - Personal experience and data from the literature. - The 2-tier grading system for laryngeal dysplasia, presented by World Health Organization in 2017, is expected to improve diagnostic reproducibility and clinical implication. However, the diagnostic criteria for low-grade dysplasia do not distinguish it clearly from basal cell hyperplasia. The World Health Organization 2017 classification of oral epithelial dysplasia remains unclear, and complicated and variable grading systems still make head and neck intraepithelial lesions difficult to interpret.
-
Seely, John Curtis; Frazier, Kendall S
2015-06-01
Renal tubule lesions often prove troublesome for toxicologic pathologists because of the diverse nature and interrelated cell types within the kidney and the presence of spontaneous lesions with overlapping morphologies similar to those induced by renal toxicants. Although there are a number of guidance documents available citing straightforward diagnostic criteria of tubule lesions for the pathologist to refer to, most are presented without further advice on the when to or to the why and the why not of diagnosing one lesion over another. Documents presenting diagnostic perspectives and recommendations derived from an author's experience are limited since guidance documents are generally based on descriptive observations. In this Regulatory Forum opinion piece, the authors attempt to dispel confusing renal tubule lesion terminology in laboratory animal species by suggesting histological advice on the recognition and interpretation of these complex entities. © 2015 by The Author(s).
-
Fox, J C; Jordan, H E; Kocan, K M; George, T J; Mullins, S T; Barnett, C E; Glenn, B L; Cowell, R L
1986-03-01
Current methods and commercial test systems for the diagnosis of parasitic infections in both animals and humans are reviewed. Lists of test kits and their manufacturers are provided along with ordering information: the only commercially available test kits are for the diagnosis of toxoplasmosis in humans or animals and dirofilariasis (heartworm) in dogs. A partial list of diagnostic laboratories and the parasite tests they perform is also provided. Complete lists of diagnostic tests that could be obtained in the private sector are not available but would be useful. Two microfluorometric solid-phase assay systems are reviewed, and adaptations to custom assays for several kinds of parasites are briefly described. User problems in performing tests and interpreting results are stressed with emphasis placed on diagnosis of dirofilariasis in dogs. False-positive serology in dogs without heartworms and negative antibody responses in micro-filariae-positive animals are discussed with respect to proper interpretation of results.
-
Diagnostic evaluation of rapid tests for scrub typhus in the Indian population is needed.
Shivalli, Siddharudha
2016-05-12
Owing to frequent outbreaks witnessed in different parts of the country in the recent past, scrub typhus is being described as a re-emerging infectious disease in India. Differentiating scrub typhus from other endemic diseases like malaria, leptospirosis, dengue fever, typhoid, etc. is difficult due to overlapping clinical features and a lower positivity for eschars in Asian populations. Hence, the diagnosis heavily relies on laboratory tests. Costs and the need of technical expertise limit the wide use of indirect immunoperoxidase or immunofluorescence assays, ELISA and PCR. The Weil-Felix test is the most commonly used and least expensive serological test, but lacks both sensitivity and specificity. Hence, the diagnosis of scrub typhus is often delayed or overlooked. With due consideration of the cost, rapidity, single test result and simplicity of interpretation, rapid diagnostic tests have come into vogue. However, evaluation of rapid diagnostic tests for scrub typhus in the Indian population is needed to justify or discourage their use. Research studies are needed to find the most suitable test in terms of the rapidity of the result, simplicity of the procedure, ease of interpretation and cost to be used in the Indian populace.
-
77 FR 6544 - Humanitarian Awards Pilot Program
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-08
..., medical diagnostics, water purification, more nutritious or higher-yield crops, pollution reduction, and... water filters, sterilization devices, and cleaner sources of energy for light, heat, cooking, or other...
-
Granja, M F; Pedraza, C M; Flórez, D C; Romero, J A; Palau, M A; Aguirre, D A
To evaluate the diagnostic performance of the length of the tumor contact with the capsule (LTC) and the apparent diffusion coefficient (ADC) map in the prediction of microscopic extracapsular extension in patients with prostate cancer who are candidates for radical prostatectomy. We used receiver operating curves to retrospectively study the diagnostic performance of the ADC map and the LTC as predictors of microscopic extracapsular extension in 92 patients with prostate cancer and moderate to high risk who were examined between May 2011 and December 2013. The optimal cutoff for the ADC map was 0.87× 10 -3 mm 2 /s, which yielded an area under the ROC curve of 72% (95% CI: 57%-86%), corresponding to a sensitivity of 83% and a specificity of 61%. The optimal cutoff for the LTC was 17.5mm, which yielded an area under the ROC curve of 74% (95% CI: 61%-87%), corresponding to a sensitivity of 91% and a specificity of 57%. Combining the two criteria improved the diagnostic performance, yielding an area under the ROC curve of 77% (95% CI: 62%-92%), corresponding to a sensitivity of 77% and a specificity of 61%. We elaborated a logistic regression model, obtaining an area under the ROC curve of 82% (95% CI: 73%-93%). Using quantitative measures improves the diagnostic accuracy of multiparametric magnetic resonance imaging in the staging of prostate cancer. The values of the ADC and LTC were predictors of microscopic extracapsular extension, and the best results were obtained when both values were used in combination. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.
-
Dhooria, Sahajal; Aggarwal, Ashutosh N; Gupta, Dheeraj; Behera, Digambar; Agarwal, Ritesh
2015-07-01
The use of endoscopic ultrasound with bronchoscope-guided fine-needle aspiration (EUS-B-FNA) has been described in the evaluation of mediastinal lymphadenopathy. Herein, we conduct a meta-analysis to estimate the overall diagnostic yield and safety of EUS-B-FNA combined with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), in the diagnosis of mediastinal lymphadenopathy. The PubMed and EmBase databases were searched for studies reporting the outcomes of EUS-B-FNA in diagnosis of mediastinal lymphadenopathy. The study quality was assessed using the QualSyst tool. The yield of EBUS-TBNA alone and the combined procedure (EBUS-TBNA and EUS-B-FNA) were analyzed by calculating the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for each study, and pooling the study results using a random effects model. Heterogeneity and publication bias were assessed for individual outcomes. The additional diagnostic gain of EUS-B-FNA over EBUS-TBNA was calculated using proportion meta-analysis. Our search yielded 10 studies (1,080 subjects with mediastinal lymphadenopathy). The sensitivity of the combined procedure was significantly higher than EBUS-TBNA alone (91% vs 80%, P = .004), in staging of lung cancer (4 studies, 465 subjects). The additional diagnostic gain of EUS-B-FNA over EBUS-TBNA was 7.6% in the diagnosis of mediastinal adenopathy. No serious complication of EUS-B-FNA procedure was reported. Clinical and statistical heterogeneity was present without any evidence of publication bias. Combining EBUS-TBNA and EUS-B-FNA is an effective and safe method, superior to EBUS-TBNA alone, in the diagnosis of mediastinal lymphadenopathy. Good quality randomized controlled trials are required to confirm the results of this systematic review. Copyright © 2015 by Daedalus Enterprises.
-
The clinical evaluation of infantile nystagmus: What to do first and why
Bertsch, Morgan; Floyd, Michael; Kehoe, Taylor; Pfeifer, Wanda; Drack, Arlene V.
2017-01-01
Introduction Infantile nystagmus has many causes, some life threatening. We determined the most common diagnoses in order to develop a testing algorithm. Methods Retrospective chart review. Exclusion criteria were no nystagmus, acquired after 6 months, or lack of examination. Data collected: pediatric eye examination findings, ancillary testing, order of testing, referral, and final diagnoses. Final diagnosis was defined as meeting published clinical criteria and/or confirmed by diagnostic testing. Patients with a diagnosis not meeting the definition were “unknown.” Patients with incomplete testing were “incomplete.” Patients with multiple plausible etiologies were “multifactorial.” Patients with negative complete workup were “motor.” Results 284 charts were identified; 202 met inclusion criteria. The 3 most common causes were Albinism(19%), Leber Congenital Amaurosis(LCA)(14%) and Non-LCA retinal dystrophy (13%). Anatomic retinal disorders comprised 10%, motor another 10%. The most common first test was MRI (74/202) with a diagnostic yield of 16%. For 28 MRI-first patients, nystagmus alone was the indication; for 46 MRI-first patients other neurologic signs were present. 0/28 nystagmus-only patients had a diagnostic MRI while 14/46 (30%) with neurologic signs did. Yield of ERG as first test was 56%, OCT 55%, and molecular genetic testing 47%. 90% of patients had an etiology identified. Conclusion The most common causes of infantile nystagmus were retinal disorders (56%), however the most common first test was brain MRI. For patients without other neurologic stigmata complete pediatric eye examination, ERG, OCT and molecular genetic testing had a higher yield than MRI scan. If MRI is not diagnostic, a complete ophthalmologic workup should be pursued. PMID:28177849
-
Davelois, Kelly; Escalante, Hermes; Jara, César
2016-01-01
. To determine the diagnostic yield using western blotting to simultaneously detect antibodies in patients with human cysticercosis, hydatidosis, and human fascioliasis. Materials and methods . Cross-sectional study of diagnostic yield assessment. Excretory/secretory antigens were obtained from Taenia solium larvae, Echinococcus granulosus cysts, and the adult flukes of Fasciola hepática, which were then separated using the polyacrylamide gel electrophoresis technique, transferred, and attached to a nitrocellulose membrane to be probed with sera from the patient infected with the three parasites. The sensitivity of the technique was assessed using 300 individual serum samples, 60 pools of two parasites, and 20 pools of three parasites with 75 sera from patients with other parasites, 10 from patients with other diseases, and 15 from patients without parasites. Results . The technique revealed 13 glycoproteins (GP): GP 35, 31, 24, 23, 18, 17, 14, and 13 kDa for cysticercosis; GP 8, 16, and 21 kDa for hydatidosis; and GP 17 and 23 kDa for fascioliasis. The test detected the presence of antibodies with a sensitivity of 96% (95% confidence interval [CI] = 94.62-98.54%) in the detection of one or the thirteen bands, a specificity of 100% (95% CI = 99.50-100.00%); individually, there was a sensitivity for cysticercosis of 97% (95% CI = 93.16-100.00%), for hydatidosis of 94% (95% CI = 88.85-99.15%) and for fascioliasis of 96% (95% CI = 91.66-100.00%). Conclusions . Western blotting is effective in the simultaneous detection of antibodies in patients with human cysticercosis, hydatidosis, and fascioliasis, and it can be used as a diagnostic test to either rule out or confirm the presence of antibodies in endemic areas.