Improved cancer detection in automated breast ultrasound by radiologists using Computer Aided Detection

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Zelst, J.C.M. van, E-mail: Jan.vanZelst@radboudumc.nl [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Tan, T.; Platel, B. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Jong, M. de [Jeroen Bosch Medical Centre, Department of Radiology, ‘s-Hertogenbosch (Netherlands); Steenbakkers, A. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Mourits, M. [Jeroen Bosch Medical Centre, Department of Radiology, ‘s-Hertogenbosch (Netherlands); Grivegnee, A. [Jules Bordet Institute, Department of Radiology, Brussels (Belgium); Borelli, C. [Catholic University of the Sacred Heart, Department of Radiological Sciences, Rome (Italy); Karssemeijer, N.; Mann, R.M. [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands)

2017-04-15

Objective: To investigate the effect of dedicated Computer Aided Detection (CAD) software for automated breast ultrasound (ABUS) on the performance of radiologists screening for breast cancer. Methods: 90 ABUS views of 90 patients were randomly selected from a multi-institutional archive of cases collected between 2010 and 2013. This dataset included normal cases (n = 40) with >1 year of follow up, benign (n = 30) lesions that were either biopsied or remained stable, and malignant lesions (n = 20). Six readers evaluated all cases with and without CAD in two sessions. CAD-software included conventional CAD-marks and an intelligent minimum intensity projection of the breast tissue. Readers reported using a likelihood-of-malignancy scale from 0 to 100. Alternative free-response ROC analysis was used to measure the performance. Results: Without CAD, the average area-under-the-curve (AUC) of the readers was 0.77 and significantly improved with CAD to 0.84 (p = 0.001). Sensitivity of all readers improved (range 5.2–10.6%) by using CAD but specificity decreased in four out of six readers (range 1.4–5.7%). No significant difference was observed in the AUC between experienced radiologists and residents both with and without CAD. Conclusions: Dedicated CAD-software for ABUS has the potential to improve the cancer detection rates of radiologists screening for breast cancer.

Error review: Can this improve reporting performance?

International Nuclear Information System (INIS)

Tudor, Gareth R.; Finlay, David B.

2001-01-01

AIM: This study aimed to assess whether error review can improve radiologists' reporting performance. MATERIALS AND METHODS: Ten Consultant Radiologists reported 50 plain radiographs, in which the diagnoses were established. Eighteen of the radiographs were normal, 32 showed an abnormality. The radiologists were shown their errors and then re-reported the series of radiographs after an interval of 4-5 months. The accuracy of the reports to the established diagnoses was assessed. Chi-square test was used to calculate the difference between the viewings. RESULTS: On re-reporting the radiographs, seven radiologists improved their accuracy score, two had a lower score and one radiologist showed no score difference. Mean accuracy pre-education was 82.2%, (range 78-92%) and post-education was 88%, (range 76-96%). Individually, two of the radiologists showed a statistically significant improvement post-education (P < 0.01,P < 0.05). Assessing the group as a whole, there was a trend for improvement post-education but this did not reach statistical significance. Assessing only the radiographs where errors were made on the initial viewing, for the group as a whole there was a 63% improvement post-education. CONCLUSION: We suggest that radiologists benefit from error review, although there was not a statistically significant improvement for the series of radiographs in total. This is partly explained by the fact that some radiologists gave incorrect responses post-education that had initially been correct, thus masking the effect of the educational intervention. Tudor, G.R. and Finlay, D.B. (2001

Decision aids for improved accuracy and standardization of mammographic diagnosis

International Nuclear Information System (INIS)

D'Orsi, C.J.; Getty, D.J.; Swets, J.A.; Pickett, R.M.; Seltzer, S.E.; McNeil, B.J.

1990-01-01

This paper examines the gains in the accuracy of mammographic diagnosis of breast cancer achievable from a pair of decision aids. Twenty-three potentially relevant perceptual features of mammograms were identified through interviews, psychometric tests, and consensus meetings with mammography specialists. Statistical analyses determined the 12 independent features that were most information diagnostically and assigned a weight to each according to its importance. Two decision aids were developed: a checklist that solicits a scale value from the radiologist for each feature and a computer program that merges those values optimally in an advisory estimate of the probability of malignancy. Six radiologists read a set of 150 cases, first in their usual way and later with the aids

Novel Method to Improve Radiologist Agreement in Interpretation of Serial Chest Radiographs in the ICU

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Denise A Castro

2015-01-01

Full Text Available Objectives: To determine whether a novel method and device, called a variable attenuation plate (VAP, which equalizes chest radiographic appearance and allows for synchronization of manual image windowing with comparison studies, would improve consistency in interpretation. Materials and Methods: Research ethics board approved the prospective cohort pilot study, which included 50 patients in the intensive care unit (ICU undergoing two serial chest radiographs with a VAP placed on each one of them. The VAP allowed for equalization of density and contrast between the patients′ serial chest radiographs. Three radiologists interpreted all the studies with and without the use of VAP. Kappa and percent agreement was used to calculate agreement between radiologists′ interpretations with and without the plate. Results: Radiologist agreement was substantially higher with the VAP method, as compared to that with the non-VAP method. Kappa values between Radiologists A and B, A and C, and B and C were 46%, 55%, and 51%, respectively, which improved to 73%, 81%, and 66%, respectively, with the use of VAP. Discrepant report impressions (i.e., one radiologist′s impression of unchanged versus one or both of the other radiologists stating improved or worsened in their impression ranged from 24 to 28.6% without the use of VAP and from 10 to 16% with the use of VAP (χ2 = 7.454, P < 0.01. Opposing views (i.e., one radiologist′s impression of improved and one of the others stating disease progression or vice versa were reported in 7 (12% cases in the non-VAP group and 4 (7% cases in the VAP group (χ2 = 0.85, P = 0.54. Conclusion: Numerous factors play a role in image acquisition and image quality, which can contribute to poor consistency and reliability of portable chest radiographic interpretations. Radiologists′ agreement of image interpretation can be improved by use of a novel method consisting of a VAP and associated software and has the potential

Artificial Intelligence: Threat or Boon to Radiologists?

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Recht, Michael; Bryan, R Nick

2017-11-01

The development and integration of machine learning/artificial intelligence into routine clinical practice will significantly alter the current practice of radiology. Changes in reimbursement and practice patterns will also continue to affect radiology. But rather than being a significant threat to radiologists, we believe these changes, particularly machine learning/artificial intelligence, will be a boon to radiologists by increasing their value, efficiency, accuracy, and personal satisfaction. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Radiologists' responses to inadequate referrals

International Nuclear Information System (INIS)

Lysdahl, Kristin Bakke; Hofmann, Bjoern Morten; Espeland, Ansgar

2010-01-01

To investigate radiologists' responses to inadequate imaging referrals. A survey was mailed to Norwegian radiologists; 69% responded. They graded the frequencies of actions related to referrals with ambiguous indications or inappropriate examination choices and the contribution of factors preventing and not preventing an examination of doubtful usefulness from being performed as requested. Ninety-five percent (344/361) reported daily or weekly actions related to inadequate referrals. Actions differed among subspecialties. The most frequent were contacting the referrer to clarify the clinical problem and checking test results/information in the medical records. Both actions were more frequent among registrars than specialists and among hospital radiologists than institute radiologists. Institute radiologists were more likely to ask the patient for additional information and to examine the patient clinically. Factors rated as contributing most to prevent doubtful examinations were high risk of serious complications/side effects, high radiation dose and low patient age. Factors facilitating doubtful examinations included respect for the referrer's judgment, patient/next-of-kin wants the examination, patient has arrived, unreachable referrer, and time pressure. In summary, radiologists facing inadequate referrals considered patient safety and sought more information. Vetting referrals on arrival, easier access to referring clinicians, and time for radiologists to handle inadequate referrals may contribute to improved use of imaging. (orig.)

Violence against radiologists. II: Psychosocial factors.

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Magnavita, N; Fileni, A

2012-09-01

Violence against radiologists is a growing problem. This study evaluated the psychosocial factors associated with this phenomenon. A questionnaire was administered to 992 Italian radiologists. Physical violence experienced in the previous 12-month period was associated with the radiologist's poor mental health [odds ratio (OR) 1.11] and overcommitment to work (OR 1.06), whereas radiologists in good physical health (OR 0.64), with job satisfaction (OR 0.96) and with overall happiness (OR 0.67) were less exposed. Nonphysical abuse was equally associated with the radiologist's poor mental health (OR 1.10) and overcommitment (OR 1.14) and negatively associated with physical health (OR 0.54), job satisfaction (OR 0.96), happiness (OR 0.81), organisational justice (OR 0.94) and social support (OR 0.80). Preventive intervention against violence in the workplace should improve workplace organisation and relationships between workers.

The influence of a continuing education program on the image interpretation accuracy of rural radiographers.

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Smith, Tony N; Traise, Peter; Cook, Aiden

2009-01-01

In regional, rural and remote clinical practice, radiographers work closely with medical members of the acute care team in the interpretation of radiographic images, particularly when no radiologist is available. However, the misreading of radiographs by non-radiologist physicians has been shown to be the most common type of clinical error in the emergency department. Further, in Australia few rural radiographers are specifically trained to interpret and report on images. This study aimed to evaluate the accuracy of a group of rural radiographers in interpreting musculoskeletal plain radiographs, and to assess the effectiveness of continuing education (CE) in improving their accuracy within a short time frame. Following ethics approval, 16 rural radiographers were recruited to the study. At inception a purpose-designed 'test-object' of 25 cases compiled by a radiologist was used to assess image interpretation accuracy. The cases were categorised into three grades of complexity. The radiographers entered their answers on a structured radiographer opinion form (ROF) that had three levels of response - 'general opinion', 'observations' and 'open comment'. Subsequent to base-line testing, the radiographers participated in a CE program aimed at improving their image interpretation skills. After a 4 month period they were re-tested using the same methodology. The ROFs were scored by the radiologist and the pooled results analysed for statistically significant changes at all ROF levels and grades of complexity. While for the small number of less complex grade 1 cases there was no change in image interpretation accuracy, for the more numerous and more complex grade 2 and grade 3 cases there was a statistically significant improvement at the 'general opinion' and 'observation' levels (paired t-test, p radiologist. However, radiographers' ability to use radiological vocabulary needs improvement. The complementary role that exists between radiographers and other members of

Investigating links between emotional intelligence and observer performance by radiologists in mammography

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Lewis, Sarah J.; Brennan, Patrick C.; Cumming, Steven; MacKay, Stuart J.; McEntee, Mark F.; Keane, Kevin; Mello-Thoms, Claudia R.

2014-03-01

A novel direction of radiology research is better understanding the links between cognitive and personality factors and radiologists' accuracy and performance. This study examines relationships between Emotional Intelligence (EI) scores and observer performance by radiologists in breast cancer detection. Three separate samples were collected with Australian and US breast imaging radiologists. The radiologists were asked to undertake a mammographic interpretation task to identify malignant breast lesions and localise them, in addition to use a confidence rating scale to report confidence in the decision. Following this activity, the radiologists were administered the EI Trait (TEIQue-SF) questionnaire. The Trait EI test gives a Global EI score and 4 sub-scores in Well-being, Self-Control, Emotionality and Sociability. Sample 1 (Sydney 2012) radiologists were divided into 2 experience bands; radiologists practicing emotionality" and "sociability" to Location Sensitivity and JAFROC. Our preliminary results indicate EI is correlated to observer performance in lesser experienced radiologists. It is suggested that tasks perceived as more difficult by less experienced radiologists may evoke more emotion (uncertainty, frustration, pressure). As experience increases, radiologists may develop an ability to control their emotions or emotional intelligence becomes less important in decision making.

Radiologists' responses to inadequate referrals

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Lysdahl, Kristin Bakke [Oslo University College, Faculty of Health Sciences, Oslo (Norway); University of Oslo, Section for Medical Ethics, Faculty of Medicine, P.O. Box 1130, Blindern, Oslo (Norway); Hofmann, Bjoern Morten [University of Oslo, Section for Medical Ethics, Faculty of Medicine, P.O. Box 1130, Blindern, Oslo (Norway); Gjoevik University College, Faculty of Health Care and Nursing, Gjoevik (Norway); Espeland, Ansgar [Haukeland University Hospital, Department of Radiology, Bergen (Norway); University of Bergen, Section for Radiology, Department of Surgical Sciences, Bergen (Norway)

2010-05-15

To investigate radiologists' responses to inadequate imaging referrals. A survey was mailed to Norwegian radiologists; 69% responded. They graded the frequencies of actions related to referrals with ambiguous indications or inappropriate examination choices and the contribution of factors preventing and not preventing an examination of doubtful usefulness from being performed as requested. Ninety-five percent (344/361) reported daily or weekly actions related to inadequate referrals. Actions differed among subspecialties. The most frequent were contacting the referrer to clarify the clinical problem and checking test results/information in the medical records. Both actions were more frequent among registrars than specialists and among hospital radiologists than institute radiologists. Institute radiologists were more likely to ask the patient for additional information and to examine the patient clinically. Factors rated as contributing most to prevent doubtful examinations were high risk of serious complications/side effects, high radiation dose and low patient age. Factors facilitating doubtful examinations included respect for the referrer's judgment, patient/next-of-kin wants the examination, patient has arrived, unreachable referrer, and time pressure. In summary, radiologists facing inadequate referrals considered patient safety and sought more information. Vetting referrals on arrival, easier access to referring clinicians, and time for radiologists to handle inadequate referrals may contribute to improved use of imaging. (orig.)

Improvement in Detection of Wrong-Patient Errors When Radiologists Include Patient Photographs in Their Interpretation of Portable Chest Radiographs.

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Tridandapani, Srini; Olsen, Kevin; Bhatti, Pamela

2015-12-01

This study was conducted to determine whether facial photographs obtained simultaneously with radiographs improve radiologists' detection rate of wrong-patient errors, when they are explicitly asked to include the photographs in their evaluation. Radiograph-photograph combinations were obtained from 28 patients at the time of portable chest radiography imaging. From these, pairs of radiographs were generated. Each unique pair consisted of one new and one old (comparison) radiograph. Twelve pairs of mismatched radiographs (i.e., pairs containing radiographs of different patients) were also generated. In phase 1 of the study, 5 blinded radiologist observers were asked to interpret 20 pairs of radiographs without the photographs. In phase 2, each radiologist interpreted another 20 pairs of radiographs with the photographs. Radiologist observers were not instructed about the purpose of the photographs but were asked to include the photographs in their review. The detection rate of mismatched errors was recorded along with the interpretation time for each session for each observer. The two-tailed Fisher exact test was used to evaluate differences in mismatch detection rates between the two phases. A p value of error detection rates without (0/20 = 0%) and with (17/18 = 94.4%) photographs were different (p = 0.0001). The average interpretation times for the set of 20 radiographs were 26.45 (SD 8.69) and 20.55 (SD 3.40) min, for phase 1 and phase 2, respectively (two-tailed Student t test, p = 0.1911). When radiologists include simultaneously obtained photographs in their review of portable chest radiographs, there is a significant improvement in the detection of labeling errors. No statistically significant difference in interpretation time was observed. This may lead to improved patient safety without affecting radiologists' throughput.

Real-Time Tele-Mentored Low Cost "Point-of-Care US" in the Hands of Paediatricians in the Emergency Department: Diagnostic Accuracy Compared to Expert Radiologists.

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Floriana Zennaro

Full Text Available The use of point-of-care ultrasonography (POC US in paediatrics is increasing. This study investigated the diagnostic accuracy of POC US in children accessing the emergency department (ED when performed by paediatricians under the remote guidance of radiologists (TELE POC.Children aged 0 to 18 years accessing the ED of a third level research hospital with eight possible clinical scenarios and without emergency/severity signs at the triage underwent three subsequent US tests: by a paediatrician guided remotely by a radiologist (TELE POC; by the same radiologist (UNBLIND RAD; by an independent blinded radiologist (BLIND RAD. Tele-radiology was implemented using low cost "commercial off-the-shelf" (COTS equipment and open-source software. Data were prospectively collected on predefined templates.Fifty-two children were enrolled, for a total of 170 ultrasound findings. Sensitivity, specificity, positive and negative predictive values of TELE POC were: 93.8, 99.7, 96.8, 99.4 when compared to UNBLIND RAD and 88.2, 99.7, 96.8, 98.7 when compared to BLIND RAD. The inter-observers agreement between the paediatricians and either the unblind or blind radiologist was excellent (k = 0.93. The mean duration of TELE POC was 6.3 minutes (95% CI 4.1 to 8.5. Technical difficulties occurred in two (3.8% cases. Quality of the transmission was rated as fair, good, very good and excellent in 7.7%, 15.4%, 42.3% and 34.6% of cases respectively, while in no case was it rated as poor.POC US performed by paediatricians in ED guided via tele-radiology by an expert radiologist (TELE POC produced reliable and timely diagnoses. Findings of this study, especially for the rarer conditions under evaluation, need further confirmation. Future research should investigate the overall benefits and the cost savings of using tele-ultrasound to perform US "at children's bedsides", under remote guidance of expert radiologists.

Does PACS improve diagnostic accuracy in chest radiograph interpretations in clinical practice?

International Nuclear Information System (INIS)

Hurlen, Petter; Borthne, Arne; Dahl, Fredrik A.; Østbye, Truls; Gulbrandsen, Pål

2012-01-01

Objectives: To assess the impact of a Picture Archiving and Communication System (PACS) on the diagnostic accuracy of the interpretation of chest radiology examinations in a “real life” radiology setting. Materials and methods: During a period before PACS was introduced to radiologists, when images were still interpreted on film and reported on paper, images and reports were also digitally stored in an image database. The same database was used after the PACS introduction. This provided a unique opportunity to conduct a blinded retrospective study, comparing sensitivity (the main outcome parameter) in the pre and post-PACS periods. We selected 56 digitally stored chest radiograph examinations that were originally read and reported on film, and 66 examinations that were read and reported on screen 2 years after the PACS introduction. Each examination was assigned a random number, and both reports and images were scored independently for pathological findings. The blinded retrospective score for the original reports were then compared with the score for the images (the gold standard). Results: Sensitivity was improved after the PACS introduction. When both certain and uncertain findings were included, this improvement was statistically significant. There were no other statistically significant changes. Conclusion: The result is consistent with prospective studies concluding that diagnostic accuracy is at least not reduced after PACS introduction. The sensitivity may even be improved.

Radiographers and trainee radiologists reporting accident radiographs: A comparative plain film-reading performance study

International Nuclear Information System (INIS)

Buskov, L.; Abild, A.; Christensen, A.; Holm, O.; Hansen, C.; Christensen, H.

2013-01-01

Aim: To compare the diagnostic accuracy and clinical validity of reporting radiographers with that of trainee radiologists whom they have recently joined in reporting emergency room radiographs at Bispebjerg University Hospital. Materials and methods: Plain radiographs of the appendicular skeleton from 1000 consecutive emergency room patients were included in the study: 500 primarily reported by radiographers and 500 by trainee radiologists. The final reporting was subsequently undertaken by a consultant radiologist in consensus with an orthopaedic surgeon. Two observers classified reports as either true positive/negative or false positive/negative based on the final report, which was considered the reference standard. To evaluate the severity of incorrect primary reports, errors were graded into three categories concerning clinical impact and erroneous reports graded as the most severe category were subsequently analysed. Mann–Whitney and Chi-squared tests were used to compare differences and associations between radiographers versus trainee radiologists regarding film reporting. Results: The sensitivity for correct diagnosis was 99% for reporting radiographers and 94% for trainee radiologists. The specificity was found to be 97% for reporting radiographers and 99% for trainee radiologists. Radiographers missed significantly fewer fractures (n = 2) than trainee radiologists (n = 14; p = 0.006) but had a higher, but not significant, degree of overcalling. No significant difference was found between groups regarding clinical impact of incorrect reporting. Conclusion: Trained radiographers report accident radiographs of the extremities with high accuracy and constitute a qualified resource to help meet increasing workload and demands in quality standards.

Social media for radiologists: an introduction.

Science.gov (United States)

Ranschaert, Erik R; van Ooijen, P M A; Lee, Simon; Ratib, Osman; Parizel, P M

2015-12-01

Social media, which can be defined as dynamic and interactive online communication forums, are becoming increasingly popular, not only for the general public but also for radiologists. In addition to assisting radiologists in finding useful profession-related information and interactive educational material in all kinds of formats, they can also contribute towards improving communication with peers, clinicians, and patients. The growing use of social networking in healthcare also has an impact on the visibility and engagement of radiologists in the online virtual community. Although many radiologists are already using social media, a large number of our colleagues are still unaware of the wide spectrum of useful information and interaction available via social media and of the added value these platforms can bring to daily practice. For many, the risk of mixing professional and private data by using social media creates a feeling of insecurity, which still keeps radiologists from using them. In this overview we aim to provide information on the potential benefits, challenges, and inherent risks of social media for radiologists. We will provide a summary of the different types of social media that can be of value for radiologists, including useful tips on how to use them safely and efficiently. • Online social networking enhances communication and collaboration between peers • Social media facilitate access to educational and scientific information • Recommendations and guidelines from policymakers and professional organisations are needed • Applications are desired for efficient and secure exchange of medical images in social media.

Measuring and managing radiologist workload: application of lean and constraint theories and production planning principles to planning radiology services in a major tertiary hospital.

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MacDonald, Sharyn L S; Cowan, Ian A; Floyd, Richard; Mackintosh, Stuart; Graham, Rob; Jenkins, Emma; Hamilton, Richard

2013-10-01

We describe how techniques traditionally used in the manufacturing industry (lean management, the theory of constraints and production planning) can be applied to planning radiology services to reduce the impact of constraints such as limited radiologist hours, and to subsequently reduce delays in accessing imaging and in report turnaround. Targets for imaging and reporting were set aligned with clinical needs. Capacity was quantified for each modality and for radiologists and recorded in activity lists. Demand was quantified and forecasting commenced based on historical referral rates. To try and mitigate the impact of radiologists as a constraint, lean management processes were applied to radiologist workflows. A production planning process was implemented. Outpatient waiting times to access imaging steadily decreased. Report turnaround times improved with the percentage of overnight/on-call reports completed by a 1030 target time increased from approximately 30% to 80 to 90%. The percentage of emergency and inpatient reports completed within one hour increased from approximately 15% to approximately 50% with 80 to 90% available within 4 hours. The number of unreported cases on the radiologist work-list at the end of the working day reduced. The average weekly accuracy for demand forecasts for emergency and inpatient CT, MRI and plain film imaging was 91%, 83% and 92% respectively. For outpatient CT, MRI and plain film imaging the accuracy was 60%, 55% and 77% respectively. Reliable routine weekly and medium to longer term service planning is now possible. Tools from industry can be successfully applied to diagnostic imaging services to improve performance. They allow an accurate understanding of the demands on a service, capacity, and can reliably predict the impact of changes in demand or capacity on service delivery. © 2013 The Royal Australian and New Zealand College of Radiologists.

Electronic Health Record-Driven Workflow for Diagnostic Radiologists.

Science.gov (United States)

Geeslin, Matthew G; Gaskin, Cree M

2016-01-01

In most settings, radiologists maintain a high-throughput practice in which efficiency is crucial. The conversion from film-based to digital study interpretation and data storage launched the era of PACS-driven workflow, leading to significant gains in speed. The advent of electronic health records improved radiologists' access to patient data; however, many still find this aspect of workflow to be relatively cumbersome. Nevertheless, the ability to guide a diagnostic interpretation with clinical information, beyond that provided in the examination indication, can add significantly to the specificity of a radiologist's interpretation. Responsibilities of the radiologist include, but are not limited to, protocoling examinations, interpreting studies, chart review, peer review, writing notes, placing orders, and communicating with referring providers. Most of the aforementioned activities are not PACS-centric and require a login to one or more additional applications. Consolidation of these tasks for completion through a single interface can simplify workflow, save time, and potentially reduce the incidence of errors. Here, the authors describe diagnostic radiology workflow that leverages the electronic health record to significantly add to a radiologist's ability to be part of the health care team, provide relevant interpretations, and improve efficiency and quality. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Effect of voice recognition on radiologist reporting time

International Nuclear Information System (INIS)

Bhan, S.N.; Coblentz, C.L.; Norman, G.R.; Ali, S.H.

2008-01-01

To study the effect that voice recognition (VR) has on radiologist reporting efficiency in a clinical setting and to identify variables associated with faster reporting time. Five radiologists were observed during the routine reporting of 402 plain radiograph studies using either VR (n 217) or conventional dictation (CD) (n = 185). Two radiologists were observed reporting 66 computed tomography (CT) studies using either VR (n - 39) or CD (n - 27). The time spent per reporting cycle, defined as the radiologist's time spent on a study from report finalization to the subsequent report finalization, was compared. As well, characteristics about the radiologist and their reporting style were collected and correlated against reporting time. For plain radiographs, radiologists took 134% (P = 0.048) more time to produce reports using VR, but there was significant variability between radiologists. Significant association with faster reporting times using VR included: English as a first language (r-0.24), use of a template (r -0.34), use of a headset microphone (r -0.46), and increased experience with VR (r -0.43). Experience as a staff radiologist and having previous study for comparison did not correlate with reporting time. For CT, there was no significant difference in reporting time identified between VR and CD (P 0.61). Overall, VR slightly decreases the reporting efficiency of radiologists. However, efficiency may be improved if English is a first language, a headset microphone, and macros and templates are use. (author)

Performance of computer-aided diagnosis for detection of lacunar infarcts on brain MR images: ROC analysis of radiologists' detection

International Nuclear Information System (INIS)

Uchiyama, Y.; Yokoyama, R.; Hara, T.; Fujita, H.; Asano, T.; Kato, H.; Hoshi, H.; Yamakawa, H.; Iwama, T.; Ando, H.; Yamakawa, H.

2007-01-01

The detection and management of asymptomatic lacunar infarcts on magnetic resonance (MR) images are important tasks for radiologists to ensure the prevention of sever cerebral infarctions. However, accurate identification of lacunar infarcts is a difficult. Therefore, we developed a computer-aided diagnosis (CAD) scheme for detection of lacunar infarcts. The purpose of this study was to evaluate radiologists' performance in detection of lacunar infarcts without and with use of CAD scheme. 30 T1- and 30 T2- weighted images obtained from 30 patients were used for an observer study, which were consisted of 15 cases with a single lacunar infarct and 15 cases without any lacunar infarct. Six radiologists participated in the observer study. They interpreted lacunar infarcts first without and then with use of the scheme. For all six observers, average area under the receiver operating characteristic curve value was increased from 0.920 to 0.965 when they used the computer output. This CAD scheme might have the potential to improve the accuracy of radiologists' performance in the detection of lacunar infarcts on MR images. (orig.)

Importance of training on clinical thinking and clinical competence to interventional radiologists

International Nuclear Information System (INIS)

Xu Ke; Zhong Hongshan

2010-01-01

Although the history of Interventional Radiology is no longer than 50 years, interventional techniques have been dramatically developed. Interventional radiologists have been responsible for much of the medical innovations and development of the minimally invasive procedures that are commonplace today to treat many complicated diseases as physicians. But the education backgrounds of interventional radiologist in China are different. Therefore, we should be aware that the job of an interventional radiologist is totally different from that of a diagnostic radiologist. It is very important to train interventional radiologists for improving their clinical thinking and clinical competence. Herein, we propose our suggestions on how to improve the clinical thinking and clinical competence of interventional radiologists. In this paper we also systemically introduce the accurate and proper treatment procedures which should be strictly followed in clinical work and,meanwhile, the perioperative patients care is emphasized. (authors)

Impact of Breast Reader Assessment Strategy on mammographic radiologists' test reading performance.

Science.gov (United States)

Suleiman, Wasfi I; Rawashdeh, Mohammad A; Lewis, Sarah J; McEntee, Mark F; Lee, Warwick; Tapia, Kriscia; Brennan, Patrick C

2016-06-01

The detection of breast cancer is somewhat limited by human factors, and thus there is a need to improve reader performance. This study assesses whether radiologists who regularly undertake the education in the form of the Breast Reader Assessment Strategy (BREAST) demonstrate any changes in mammography interpretation performance over time. In 2011, 2012 and 2013, 14 radiologists independently assessed a year-specific BREAST mammographic test-set. Radiologists read a different single test-set once each year, with each comprising 60 digital mammogram cases. Radiologists marked the location of suspected lesions without computer-aided diagnosis (CAD) and assigned a confidence rating of 2 for benign and 3-5 for malignant lesions. The mean sensitivity, specificity, location sensitivity, JAFROC FOM and ROC AUC were calculated. A Kruskal-Wallis test was used to compare the readings for the 14 radiologists across the 3 years. Wilcoxon signed rank test was used to assess comparison between pairs of years. Relationships between changes in performance and radiologist characteristics were examined using a Spearman's test. Significant increases were noted in mean sensitivity (P = 0.01), specificity (P = 0.01), location sensitivity (P = 0.001) and JAFROC FOM (P = 0.001) between 2011 and 2012. Between 2012 and 2013, significant improvements were noted in mean sensitivity (P = 0.003), specificity (P = 0.002), location sensitivity (P = 0.02), JAFROC FOM (P = 0.005) and ROC AUC (P = 0.008). No statistically significant correlations were shown between the levels of improvement and radiologists' characteristics. Radiologists' who undertake the BREAST programme demonstrate significant improvements in test-set performance during a 3-year period, highlighting the value of ongoing education through the use of test-set. © 2016 The Royal Australian and New Zealand College of Radiologists.

Cadastral Database Positional Accuracy Improvement

Science.gov (United States)

Hashim, N. M.; Omar, A. H.; Ramli, S. N. M.; Omar, K. M.; Din, N.

2017-10-01

Positional Accuracy Improvement (PAI) is the refining process of the geometry feature in a geospatial dataset to improve its actual position. This actual position relates to the absolute position in specific coordinate system and the relation to the neighborhood features. With the growth of spatial based technology especially Geographical Information System (GIS) and Global Navigation Satellite System (GNSS), the PAI campaign is inevitable especially to the legacy cadastral database. Integration of legacy dataset and higher accuracy dataset like GNSS observation is a potential solution for improving the legacy dataset. However, by merely integrating both datasets will lead to a distortion of the relative geometry. The improved dataset should be further treated to minimize inherent errors and fitting to the new accurate dataset. The main focus of this study is to describe a method of angular based Least Square Adjustment (LSA) for PAI process of legacy dataset. The existing high accuracy dataset known as National Digital Cadastral Database (NDCDB) is then used as bench mark to validate the results. It was found that the propose technique is highly possible for positional accuracy improvement of legacy spatial datasets.

Performance of computer-aided diagnosis for detection of lacunar infarcts on brain MR images: ROC analysis of radiologists' detection

Energy Technology Data Exchange (ETDEWEB)

Uchiyama, Y.; Yokoyama, R.; Hara, T.; Fujita, H. [Dept. of Intelligent Image Information, Graduate Scholl of Medicine, Gifu Univ. (Japan); Asano, T.; Kato, H.; Hoshi, H. [Dept. of Radiology, Graduate Scholl of Medicine, Gifu Univ. (Japan); Yamakawa, H.; Iwama, T. [Dept. of Neurosurgery, Graduate Scholl of Medicine, Gifu Univ. (Japan); Ando, H. [Dept. of Neurosurgery, Gifu Municipal Hospital (Japan); Yamakawa, H. [Dept. of Emergency and Critical Care Medicine, Chuno-Kousei Hospital (Japan)

2007-06-15

The detection and management of asymptomatic lacunar infarcts on magnetic resonance (MR) images are important tasks for radiologists to ensure the prevention of sever cerebral infarctions. However, accurate identification of lacunar infarcts is a difficult. Therefore, we developed a computer-aided diagnosis (CAD) scheme for detection of lacunar infarcts. The purpose of this study was to evaluate radiologists' performance in detection of lacunar infarcts without and with use of CAD scheme. 30 T1- and 30 T2- weighted images obtained from 30 patients were used for an observer study, which were consisted of 15 cases with a single lacunar infarct and 15 cases without any lacunar infarct. Six radiologists participated in the observer study. They interpreted lacunar infarcts first without and then with use of the scheme. For all six observers, average area under the receiver operating characteristic curve value was increased from 0.920 to 0.965 when they used the computer output. This CAD scheme might have the potential to improve the accuracy of radiologists' performance in the detection of lacunar infarcts on MR images. (orig.)

Measuring and managing radiologist workload: application of lean and constraint theories and production planning principles to planning radiology services in mahjor tertiary hospital

International Nuclear Information System (INIS)

MacDonald, Sharyn L.S.; Cowan, Ian A.; Floyd, Richard; Mackintosh, Stuart; Graham, Rob; Jenkins, Emma; Hamilton, Richard

2013-01-01

We describe how techniques traditionally used in the manufacturing industry (lean management, the theory of constraints and production planning) can be applied to planning radiology services to reduce the impact of constraints such as limited radiologist hours, and to subsequently reduce delays in accessing imaging and in report turnaround. Targets for imaging and reporting were set aligned with clinical needs. Capacity was quantified for each modality and for radiologists and recorded in activity lists. Demand was quantified and forecasting commenced based on historical referral rates. To try and mitigate the impact of radiologists as a constraint, lean management processes were applied to radiologist workflows. A production planning process was implemented. Outpatient waiting times to access imaging steadily decreased. Report turnaround times improved with the percentage of overnight/on-call reports completed by a 1030 target time increased from approximately 30% to 80 to 90%. The percentage of emergency and inpatient reports completed within one hour increased from approximately 15% to approximately 50% with 80 to 90% available within 4 hours. The number of unreported cases on the radiologist work-list at the end of the working day reduced. The average weekly accuracy for demand forecasts for emergency and inpatient CT, MRI and plain film imaging was 91%, 83% and 92% respectively. For outpatient CT, MRI and plain film imaging the accuracy was 60%, 55% and 77% respectively. Reliable routine weekly and medium to longer term service planning is now possible. Tools from industry can be successfully applied to diagnostic imaging services to improve performance. They allow an accurate understanding of the demands on a service, capacity, and can reliably predict the impact of changes in demand or capacity on service delivery.

Clinical application of S-Detect to breast masses on ultrasonography: A study evaluating the diagnostic performance and agreement with a dedicated breast radiologist

International Nuclear Information System (INIS)

Kim, Ki Wook; Kim, Eun Kyung; Yoon, Jung Hyun; Song, Mi Kyung

2017-01-01

The purpose of this study was to evaluate the diagnostic performance of S-Detect when applied to breast ultrasonography (US), and the agreement with an experienced radiologist specializing in breast imaging. From June to August 2015, 192 breast masses in 175 women were included. US features of the breast masses were retrospectively analyzed by a radiologist who specializes in breast imaging and S-Detect, according to the fourth edition of the American College of Radiology Breast Imaging Reporting and Data System lexicon and final assessment categories. Final assessments from S-Detect were in dichotomized form: possibly benign and possibly malignant. Kappa statistics were used to analyze the agreement between the radiologist and S-Detect. Diagnostic performance of the radiologist and S-Detect was calculated, including sensitivity, specificity, positive predictive value (PPV), negative predictive value, accuracy, and area under the receiving operator characteristics curve. Of the 192 breast masses, 72 (37.5%) were malignant, and 120 (62.5%) were benign. Benign masses among category 4a had higher rates of possibly benign assessment on S-Detect for the radiologist, 63.5% to 36.5%, respectively (P=0.797). When the cutoff was set at category 4a, the specificity, PPV, and accuracy was significantly higher in S-Detect compared to the radiologist (all P<0.05), with a higher area under the receiver operator characteristics curve of 0.725 compared to 0.653 (P=0.038). Moderate agreement (k=0.58) was seen in the final assessment between the radiologist and S-Detect. S-Detect may be used as an additional diagnostic tool to improve the specificity of breast US in clinical practice, and guide in decision making for breast masses detected on US

Computer-aided diagnosis for classifying benign versus malignant thyroid nodules based on ultrasound images: A comparison with radiologist-based assessments

Energy Technology Data Exchange (ETDEWEB)

Chang, Yongjun [School of Electrical Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Yuseong-gu, Daejeon 34141 (Korea, Republic of); Paul, Anjan Kumar [Funzin, Inc., 148 Ankuk-dong, Jongro-gu, Seoul 03060 (Korea, Republic of); Kim, Namkug, E-mail: namkugkim@gmail.com; Baek, Jung Hwan; Choi, Young Jun [Department of Radiology, University of Ulsan College of Medicine, 388-1 Pungnap2-dong, Songpa-gu, Seoul 05505 (Korea, Republic of); Ha, Eun Ju [Department of Radiology, Ajou University School of Medicine, Wonchon-Dong, Yeongtong-Gu, Suwon 16499 (Korea, Republic of); Lee, Kang Dae; Lee, Hyoung Shin [Department of Otolaryngology Head and Neck Surgery, Kosin University College of Medicine, 34 Amnamdong, Seu-Gu, Busan 49267 (Korea, Republic of); Shin, DaeSeock; Kim, Nakyoung [MIDAS Information Technology, Pangyo-ro 228, Bundang-gu, Seongnam-si, Gyeonggi 13487 (Korea, Republic of)

2016-01-15

Purpose: To develop a semiautomated computer-aided diagnosis (CAD) system for thyroid cancer using two-dimensional ultrasound images that can be used to yield a second opinion in the clinic to differentiate malignant and benign lesions. Methods: A total of 118 ultrasound images that included axial and longitudinal images from patients with biopsy-confirmed malignant (n = 30) and benign (n = 29) nodules were collected. Thyroid CAD software was developed to extract quantitative features from these images based on thyroid nodule segmentation in which adaptive diffusion flow for active contours was used. Various features, including histogram, intensity differences, elliptical fit, gray-level co-occurrence matrixes, and gray-level run-length matrixes, were evaluated for each region imaged. Based on these imaging features, a support vector machine (SVM) classifier was used to differentiate benign and malignant nodules. Leave-one-out cross-validation with sequential forward feature selection was performed to evaluate the overall accuracy of this method. Additionally, analyses with contingency tables and receiver operating characteristic (ROC) curves were performed to compare the performance of CAD with visual inspection by expert radiologists based on established gold standards. Results: Most univariate features for this proposed CAD system attained accuracies that ranged from 78.0% to 83.1%. When optimal SVM parameters that were established using a grid search method with features that radiologists use for visual inspection were employed, the authors could attain rates of accuracy that ranged from 72.9% to 84.7%. Using leave-one-out cross-validation results in a multivariate analysis of various features, the highest accuracy achieved using the proposed CAD system was 98.3%, whereas visual inspection by radiologists reached 94.9% accuracy. To obtain the highest accuracies, “axial ratio” and “max probability” in axial images were most frequently included in the

Effect of radiologists' diagnostic work-up volume on interpretive performance.

Science.gov (United States)

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

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.

MRI of the knee: how do field strength and radiologist's experience influence diagnostic accuracy and interobserver correlation in assessing chondral and meniscal lesions and the integrity of the anterior cruciate ligament?

International Nuclear Information System (INIS)

Krampla, W.; Roesel, M.; Svoboda, K.; Nachbagauer, A.; Gschwantler, M.; Hruby, W.

2009-01-01

Accuracy of MRI reports is taken for granted. In this paper the inter-observer reliability in the interpretation of meniscal lesions, degree of chondropathy, and integrity of the ACL was analyzed while taking the radiologist's experience and field strength into account. Fifty-two MRI studies of knees were interpreted by 11 radiologists independently. Twenty-two were acquired on 1.0-T, 20 on 1.5-T, and 10 on 3.0-T systems. Four of the radiologists had more than 5 years and seven had 3 to 5 years of experience in interpreting MRI studies. The findings were compared with the intra-operative findings. Inter-observer variance, specificity, and sensitivity were evaluated for each field strength. Inter-observer correlation ranged between 0.370 for cartilage lesions and 0.597 for meniscal tears. Correlation values did not increase with experience or field strength. The number of false reports was dependent on the observer, but not on field strength. The rate of false interpretations was significantly higher for most criteria in the less experienced group. In conclusion, inter-observer correlation was low, although the diagnostic criteria were defined. The use of the classification scheme should be standardized by uniform training. Radiologist experience seems to be more important than field strength. (orig.)

Interactive dedicated training curriculum improves accuracy in the interpretation of MR imaging of prostate cancer

International Nuclear Information System (INIS)

Akin, Oguz; Zhang, Jingbo; Hricak, Hedvig; Riedl, Christopher C.; Ishill, Nicole M.; Moskowitz, Chaya S.

2010-01-01

To assess the effect of interactive dedicated training on radiology fellows' accuracy in assessing prostate cancer on MRI. Eleven radiology fellows, blinded to clinical and pathological data, independently interpreted preoperative prostate MRI studies, scoring the likelihood of tumour in the peripheral and transition zones and extracapsular extension. Each fellow interpreted 15 studies before dedicated training (to supply baseline interpretation accuracy) and 200 studies (10/week) after attending didactic lectures. Expert radiologists led weekly interactive tutorials comparing fellows' interpretations to pathological tumour maps. To assess interpretation accuracy, receiver operating characteristic (ROC) analysis was conducted, using pathological findings as the reference standard. In identifying peripheral zone tumour, fellows' average area under the ROC curve (AUC) increased from 0.52 to 0.66 (after didactic lectures; p < 0.0001) and remained at 0.66 (end of training; p < 0.0001); in the transition zone, their average AUC increased from 0.49 to 0.64 (after didactic lectures; p = 0.01) and to 0.68 (end of training; p = 0.001). In detecting extracapsular extension, their average AUC increased from 0.50 to 0.67 (after didactic lectures; p = 0.003) and to 0.81 (end of training; p < 0.0001). Interactive dedicated training significantly improved accuracy in tumour localization and especially in detecting extracapsular extension on prostate MRI. (orig.)

Interactive dedicated training curriculum improves accuracy in the interpretation of MR imaging of prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Akin, Oguz; Zhang, Jingbo; Hricak, Hedvig [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States); Riedl, Christopher C. [Memorial Sloan-Kettering Cancer Center, Department of Radiology, New York, NY (United States); Medical University of Vienna, Department of Radiology, Vienna (Austria); Ishill, Nicole M.; Moskowitz, Chaya S. [Memorial Sloan-Kettering Cancer Center, Epidemiology and Biostatistics, New York, NY (United States)

2010-04-15

To assess the effect of interactive dedicated training on radiology fellows' accuracy in assessing prostate cancer on MRI. Eleven radiology fellows, blinded to clinical and pathological data, independently interpreted preoperative prostate MRI studies, scoring the likelihood of tumour in the peripheral and transition zones and extracapsular extension. Each fellow interpreted 15 studies before dedicated training (to supply baseline interpretation accuracy) and 200 studies (10/week) after attending didactic lectures. Expert radiologists led weekly interactive tutorials comparing fellows' interpretations to pathological tumour maps. To assess interpretation accuracy, receiver operating characteristic (ROC) analysis was conducted, using pathological findings as the reference standard. In identifying peripheral zone tumour, fellows' average area under the ROC curve (AUC) increased from 0.52 to 0.66 (after didactic lectures; p < 0.0001) and remained at 0.66 (end of training; p < 0.0001); in the transition zone, their average AUC increased from 0.49 to 0.64 (after didactic lectures; p = 0.01) and to 0.68 (end of training; p = 0.001). In detecting extracapsular extension, their average AUC increased from 0.50 to 0.67 (after didactic lectures; p = 0.003) and to 0.81 (end of training; p < 0.0001). Interactive dedicated training significantly improved accuracy in tumour localization and especially in detecting extracapsular extension on prostate MRI. (orig.)

Volumetry of Artificial Pulmonary Nodules in Ex Vivo Porcine Lungs: Comparison of Semi-automated Volumetry and Radiologists' Performance

International Nuclear Information System (INIS)

Jeong, Ju Hyeon; Kim, Jin Hwan; Kim, Song Soo; Jeon, Ho Sang; Lee, Hyun Ju; Park, Noh Hyuck; Cho, Gyu Seong

2010-01-01

With the advent of MSCT, the detection rate of small pulmonary nodules is markedly greater. However, there is no definite diagnostic clue to differentiate between malignant and benign nodules, except for the interval growth in small nodule less than 1 cm in diameter. We evaluated the accuracy of computer aided volumetry (CAV) and compared it with 4 radiologists' measurement. Fifteen artificial nodules that were embedded in the ex vivo porcine lung were scanned by MSCT. The diameters and volumes of nodules were independently measured three times, at 5-day intervals, and by four radiologists as well as by CAV. We evaluated the accuracy of the measurements on the basis of the true diameter and volume of the nodules. Using a paired t-test and a Bland-Altman plot, we evaluated whether there was a statistically significant difference between the radiologists' measurements and the CAV. The accuracy of the manual measurements by radiologists revealed a statistically significant difference from the true diameter and volume of the artificial nodules (p 0.01) The results of this study suggest that CAV is an accurate and useful tool to evaluate the volume of pulmonary nodules and can eventually be used to differentiate malignant and benign nodules as well as evaluate the therapeutic response of lung cancer

Diagnostic Performance on Low Dose Computed Tomography For Acute Appendicitis Among Attending and Resident Radiologists

International Nuclear Information System (INIS)

Chang, Chih-Chen; Wong, Yon-Cheong; Wu, Cheng-Hsien; Chen, Huan-Wu; Wang, Li-Jen; Lee, Yu-Hsien; Wu, Patricia Wanping; Irama, Wiwan; Chen, Wei Yuan; Chang, Chee-Jen

2016-01-01

Low-dose computed tomography (LDCT) techniques can reduce exposure to radiation. Several previous studies have shown that radiation dose reduction in LDCT does not decrease the diagnostic performance for appendicitis among attending radiologists. But, the LDCT diagnostic performance for acute appendicitis in radiology residents with variable training levels has not been well discussed. To compare inter-observer and intra-observer differences of diagnostic performance on non-enhanced LDCT (NE-LDCT) and contrast-enhanced standard dose CT (CE-SDCT) for acute appendicitis among attending and resident radiologists. This retrospective study included 101 patients with suspected acute appendicitis who underwent NE-LDCT and CE-SDCT. The CT examinations were interpreted and recorded on a five-point scale independently by three attending radiologists and three residents with 4, 1 and 1 years of training. Diagnostic performance for acute appendicitis of all readers on both examinations was represented by area under receiver operating characteristic (ROC) curves. Inter-observer and intra-observer AUC values were compared using Jackknife FROC software on both modalities. The diagnostic accuracy of each reader on NE-LDCT was compared with body mass index (BMI) subgroups and noise using independent T test. Diagnostic performances for acute appendicitis were not statistically different for attending radiologists at both examinations. Better performance was noted on the CE-SDCT with a borderline significant difference (P = 0.05) for senior radiology resident. No statistical difference of AUC values was observed between attending radiologists and fourth year resident on both examinations. Statistically signifi@@cant differences of AUC values were observed between attending radiologists and first year residents (P = 0.001 ~ 0.018) on NE-LDCT. Diagnostic accuracies of acute appendicitis on NE-LDCT for each reader were not significantly related to BMI or noise. Attending radiologists

Social networks and expertise development for Australian breast radiologists.

Science.gov (United States)

Taba, Seyedamir Tavakoli; Hossain, Liaquat; Willis, Karen; Lewis, Sarah

2017-02-11

In this study, we explore the nexus between social networks and expertise development of Australian breast radiologists. Background literature has shown that a lack of appropriate social networks and interaction among certain professional group(s) may be an obstacle for knowledge acquisition, information flow and expertise sharing. To date there have not been any systematic studies investigating how social networks and expertise development are interconnected and whether this leads to improved performance for breast radiologists. This study explores the value of social networks in building expertise alongside with other constructs of performance for the Australian radiology workforce using semi-structured in-depth interviews with 17 breast radiologists. The findings from this study emphasise the influences of knowledge transfer and learning through social networks and interactions as well as knowledge acquisition and development through experience and feedback. The results also show that accessibility to learning resources and a variety of timely feedback on performance through the information and communication technologies (ICT) is likely to facilitate improved performance and build social support. We argue that radiologists' and, in particular, breast radiologists' work performance, needs to be explored not only through individual numerical characteristics but also by analysing the social context and peer support networks in which they operate and we identify multidisciplinary care as a core entity of social learning.

Radiographers and radiologists reporting plain radiograph requests from accident and emergency and general practice

International Nuclear Information System (INIS)

Brealey, S.D.; King, D.G.; Hahn, S.; Crowe, M.; Williams, P.; Rutter, P.; Crane, S.

2005-01-01

AIM: To assess selectively trained radiographers and consultant radiologists reporting plain radiographs for the Accident and Emergency Department (A and E) and general practitioners (GPs) within a typical hospital setting. METHODS: Two radiographers, a group of eight consultant radiologists, and a reference standard radiologist independently reported under controlled conditions a retrospectively selected, random, stratified sample of 400 A and E and 400 GP plain radiographs. An independent consultant radiologist judged whether the radiographer and radiologist reports agreed with the reference standard report. Clinicians then assessed whether radiographer and radiologist incorrect reports affected confidence in their diagnosis and treatment plans, and patient outcome. RESULTS: For A and E and GP plain radiographs, respectively, there was a 1% (95% confidence interval (CI) -2 to 5) and 4% (95% CI -1 to 8) difference in reporting accuracy between the two professional groups. For both A and E and GP cases there was an 8% difference in the clinicians' confidence in their diagnosis based on radiographer or radiologist incorrect reports. For A and E and GP cases, respectively, there was a 2% and 8% difference in the clinicians' confidence in their management plans based on radiographer or radiologist incorrect reports. For A and E and GP cases, respectively, there was a 1% and 11% difference in effect on patient outcome of radiographer or radiologist incorrect reports. CONCLUSION: There is the potential to extend the reporting role of selectively trained radiographers to include plain radiographs for all A and E and GP patients. Further research conducted during clinical practice at a number of sites is recommended

Volumetry of Artificial Pulmonary Nodules in Ex Vivo Porcine Lungs: Comparison of Semi-automated Volumetry and Radiologists' Performance

Energy Technology Data Exchange (ETDEWEB)

Jeong, Ju Hyeon; Kim, Jin Hwan; Kim, Song Soo [Chungnam National University Hospital, Daejeon (Korea, Republic of); Jeon, Ho Sang [Pusan National University Yangsan Hospital, Yangsan (Korea, Republic of); Lee, Hyun Ju [Seoul National University Hospital, Seoul (Korea, Republic of); Park, Noh Hyuck [Kwandong University College of Medicine, Myungji Hospital, Goyang (Korea, Republic of); Cho, Gyu Seong [KAIST, Daejeon (Korea, Republic of)

2010-10-15

With the advent of MSCT, the detection rate of small pulmonary nodules is markedly greater. However, there is no definite diagnostic clue to differentiate between malignant and benign nodules, except for the interval growth in small nodule less than 1 cm in diameter. We evaluated the accuracy of computer aided volumetry (CAV) and compared it with 4 radiologists' measurement. Fifteen artificial nodules that were embedded in the ex vivo porcine lung were scanned by MSCT. The diameters and volumes of nodules were independently measured three times, at 5-day intervals, and by four radiologists as well as by CAV. We evaluated the accuracy of the measurements on the basis of the true diameter and volume of the nodules. Using a paired t-test and a Bland-Altman plot, we evaluated whether there was a statistically significant difference between the radiologists' measurements and the CAV. The accuracy of the manual measurements by radiologists revealed a statistically significant difference from the true diameter and volume of the artificial nodules (p<0.01). Conversely, the accuracy of CAV did not show a statistically significant difference with the true nodule diameter and volume (p>0.01) The results of this study suggest that CAV is an accurate and useful tool to evaluate the volume of pulmonary nodules and can eventually be used to differentiate malignant and benign nodules as well as evaluate the therapeutic response of lung cancer.

Improving Accuracy of Processing Through Active Control

Directory of Open Access Journals (Sweden)

N. N. Barbashov

2016-01-01

Full Text Available An important task of modern mathematical statistics with its methods based on the theory of probability is a scientific estimate of measurement results. There are certain costs under control, and under ineffective control when a customer has got defective products these costs are significantly higher because of parts recall.When machining the parts, under the influence of errors a range scatter of part dimensions is offset towards the tolerance limit. To improve a processing accuracy and avoid defective products involves reducing components of error in machining, i.e. to improve the accuracy of machine and tool, tool life, rigidity of the system, accuracy of the adjustment. In a given time it is also necessary to adapt machine.To improve an accuracy and a machining rate there, currently  become extensively popular various the in-process gaging devices and controlled machining that uses adaptive control systems for the process monitoring. Improving the accuracy in this case is compensation of a majority of technological errors. The in-cycle measuring sensors (sensors of active control allow processing accuracy improvement by one or two quality and provide a capability for simultaneous operation of several machines.Efficient use of in-cycle measuring sensors requires development of methods to control the accuracy through providing the appropriate adjustments. Methods based on the moving average, appear to be the most promising for accuracy control since they include data on the change in some last measured values of the parameter under control.

Image quality preferences among radiographers and radiologists. A conjoint analysis

International Nuclear Information System (INIS)

Ween, Borgny; Kristoffersen, Doris Tove; Hamilton, Glenys A.; Olsen, Dag Rune

2005-01-01

Purpose: The aim of this study was to investigate the image quality preferences among radiographers and radiologists. The radiographers' preferences are mainly related to technical parameters, whereas radiologists assess image quality based on diagnostic value. Methods: A conjoint analysis was undertaken to survey image quality preferences; the study included 37 respondents: 19 radiographers and 18 radiologists. Digital urograms were post-processed into 8 images with different properties of image quality for 3 different patients. The respondents were asked to rank the images according to their personally perceived subjective image quality. Results: Nearly half of the radiographers and radiologists were consistent in their ranking of the image characterised as 'very best image quality'. The analysis showed, moreover, that chosen filtration level and image intensity were responsible for 72% and 28% of the preferences, respectively. The corresponding figures for each of the two professions were 76% and 24% for the radiographers, and 68% and 32% for the radiologists. In addition, there were larger variations in image preferences among the radiologists, as compared to the radiographers. Conclusions: Radiographers revealed a more consistent preference than the radiologists with respect to image quality. There is a potential for image quality improvement by developing sets of image property criteria

Reassessment of CT images to improve diagnostic accuracy in patients with suspected acute appendicitis and an equivocal preoperative CT interpretation

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Cheol; Yang, Dal Mo; Kim, Sang Won [Kyung Hee University Hospital at Gangdong, College of Medicine, Kyung Hee University, Department of Radiology, Seoul (Korea, Republic of); Park, Seong Jin [Kyung Hee University Hospital, College of Medicine, Kyung Hee University, Department of Radiology, Seoul (Korea, Republic of)

2012-06-15

To identify CT features that discriminate individuals with and without acute appendicitis in patients with equivocal CT findings, and to assess whether knowledge of these findings improves diagnostic accuracy. 53 patients that underwent appendectomy with an indeterminate preoperative CT interpretation were selected and allocated to an acute appendicitis group or a non-appendicitis group. The 53 CT examinations were reviewed by two radiologists in consensus to identify CT findings that could aid in the discrimination of those with and without appendicitis. In addition, two additional radiologists were then requested to evaluate independently the 53 CT examinations using a 4-point scale, both before and after being informed of the potentially discriminating criteria. CT findings found to be significantly different in the two groups were; the presence of appendiceal wall enhancement, intraluminal air in appendix, a coexistent inflammatory lesion, and appendiceal wall thickening (P < 0.05). Areas under the curves of reviewers 1 and 2 significantly increased from 0.516 and 0.706 to 0.677 and 0.841, respectively, when reviewers were told which CT variables were significant (P = 0.0193 and P = 0.0397, respectively). Knowledge of the identified CT findings was found to improve diagnostic accuracy for acute appendicitis in patients with equivocal CT findings. circle Numerous patients with clinically equivocal appendicitis do not have acute appendicitis circle Computed tomography (CT) helps to reduce the negative appendectomy rate circle CT is not always infallible and may also demonstrate indeterminate findings circle However knowledge of significant CT variables can further reduce negative appendectomy rate circle An equivocal CT interpretation of appendicitis should be reassessed with this knowledge. (orig.)

Reassessment of CT images to improve diagnostic accuracy in patients with suspected acute appendicitis and an equivocal preoperative CT interpretation

International Nuclear Information System (INIS)

Kim, Hyun Cheol; Yang, Dal Mo; Kim, Sang Won; Park, Seong Jin

2012-01-01

To identify CT features that discriminate individuals with and without acute appendicitis in patients with equivocal CT findings, and to assess whether knowledge of these findings improves diagnostic accuracy. 53 patients that underwent appendectomy with an indeterminate preoperative CT interpretation were selected and allocated to an acute appendicitis group or a non-appendicitis group. The 53 CT examinations were reviewed by two radiologists in consensus to identify CT findings that could aid in the discrimination of those with and without appendicitis. In addition, two additional radiologists were then requested to evaluate independently the 53 CT examinations using a 4-point scale, both before and after being informed of the potentially discriminating criteria. CT findings found to be significantly different in the two groups were; the presence of appendiceal wall enhancement, intraluminal air in appendix, a coexistent inflammatory lesion, and appendiceal wall thickening (P < 0.05). Areas under the curves of reviewers 1 and 2 significantly increased from 0.516 and 0.706 to 0.677 and 0.841, respectively, when reviewers were told which CT variables were significant (P = 0.0193 and P = 0.0397, respectively). Knowledge of the identified CT findings was found to improve diagnostic accuracy for acute appendicitis in patients with equivocal CT findings. circle Numerous patients with clinically equivocal appendicitis do not have acute appendicitis circle Computed tomography (CT) helps to reduce the negative appendectomy rate circle CT is not always infallible and may also demonstrate indeterminate findings circle However knowledge of significant CT variables can further reduce negative appendectomy rate circle An equivocal CT interpretation of appendicitis should be reassessed with this knowledge. (orig.)

Magnetic resonance imaging and magnetic resonance arthrography of the shoulder: dependence on the level of training of the performing radiologist for diagnostic accuracy

Energy Technology Data Exchange (ETDEWEB)

Theodoropoulos, John S. [University of Toronto, Division of Orthopaedics, Mount Sinai Hospital and the University Health Network, Toronto, ON (Canada); Andreisek, Gustav [University of Toronto, Department of Medical Imaging, Mount Sinai Hospital and the University Health Network, Toronto, ON (Canada); University Hospital Zuerich, Institute for Diagnostic Radiology, Zuerich (Switzerland); Harvey, Edward J. [McGill University, Division of Orthopaedics, MUHC - Montreal General Hospital, Montreal, Quebec (Canada); Wolin, Preston [Center for Athletic Medicine, Chicago, IL (United States)

2010-07-15

Discrepancies were identified between magnetic resonance (MR) imaging and clinical findings in patients who had MR imaging examinations evaluated by community-based general radiologists. The purpose of this study was to evaluate the diagnostic performance of MR imaging examinations of the shoulder with regard to the training level of the performing radiologist. A review of patient charts identified 238 patients (male/female, 175/63; mean age, 40.4 years) in whom 250 arthroscopies were performed and who underwent MR imaging or direct MR arthrography in either a community-based or hospital-based institution prior to surgery. All MR imaging and surgical reports were reviewed and the diagnostic performance for the detection of labral, rotator cuff, biceps, and Hill-Sachs lesions was determined. Kappa and Student's t test analyses were performed in a subset of cases in which initial community-based MR images were re-evaluated by hospital-based musculoskeletal radiologists, to determine the interobserver agreement and any differences in image interpretation. The diagnostic performance of community-based general radiologists was lower than that of hospital-based sub-specialized musculoskeletal radiologists. A sub-analysis of re-evaluated cases showed that musculoskeletal radiologists performed better. {kappa} values were 0.208, 0.396, 0.376, and 0.788 for labral, rotator cuff, biceps, and Hill-Sachs lesions (t test statistics: p =<0.001, 0.004, 0.019, and 0.235). Our results indicate that the diagnostic performance of MR imaging and MR arthrography of the shoulder depends on the training level of the performing radiologist, with sub-specialized musculoskeletal radiologists having a better diagnostic performance than general radiologists. (orig.)

Reading screening mammograms – Attitudes among radiologists and radiographers about skill mix

International Nuclear Information System (INIS)

Johansen, Lena Westphal; Brodersen, John

2011-01-01

Introduction: Because of shortage of personnel for the Danish mammography screening programme, the aim of this study was to investigate the attitudes of radiologists and radiographers towards a future implementation of radiographers reading screening mammograms. Materials and methods: Seven combined phenomenological and hermeneutical interviews with radiographers and radiologists were performed. Stratified selection was used for sampling of informants. The interviews were analysed against theory about quality, organization and profession. Results: Quality related possibilities: radiographers do routinely measure the performance quality, radiographers obtain sufficient reading qualifications, and skill mix improves quality. Quality related obstacles: radiologists do not routinely measure performance quality. Organization related possibilities: shortage of radiologists, positive attitudes of managers, and improved working relations. Organization related obstacles: shortage of radiographers and negative attitudes of managers. Professional related possibilities: positive experience with skill mix. Professional related obstacles: worries about negative consequences for the training of radiologists, and resistance against handing over tasks to another profession. Conclusion: Attitudes towards radiographers reading screening mammograms are attached to either quality-, organisational or professional perspectives. Radiographers are capable of learning to read mammograms at sufficient performance level but routine measurement of performance quality is essential. Resistance against skill mix may be caused by an emotionally conditioned fear of losing demarcations. The main motive for skill mix is improvement of the utilization of resources. No evidence was found regarding the organisational and financial consequences of skill mix. Despite of this all radiologists and radiographers experienced with skill mix were strong advocates for reading radiographers.

A Novel Reporting System to Improve Accuracy in Appendicitis Imaging

Science.gov (United States)

Godwin, Benjamin D.; Drake, Frederick T.; Simianu, Vlad V.; Shriki, Jabi E.; Hippe, Daniel S.; Dighe, Manjiri; Bastawrous, Sarah; Cuevas, Carlos; Flum, David; Bhargava, Puneet

2015-01-01

OBJECTIVE The purpose of this study was to ascertain if standardized radiologic reporting for appendicitis imaging increases diagnostic accuracy. MATERIALS AND METHODS We developed a standardized appendicitis reporting system that includes objective imaging findings common in appendicitis and a certainty score ranging from 1 (definitely not appendicitis) through 5 (definitely appendicitis). Four radiologists retrospectively reviewed the preoperative CT scans of 96 appendectomy patients using our reporting system. The presence of appendicitis-specific imaging findings and certainty scores were compared with final pathology. These comparisons were summarized using odds ratios (ORs) and the AUC. RESULTS The appendix was visualized on CT in 89 patients, of whom 71 (80%) had pathologically proven appendicitis. Imaging findings associated with appendicitis included appendiceal diameter (odds ratio [OR] = 14 [> 10 vs appendicitis. In this initially indeterminate group, using the standardized reporting system, radiologists assigned higher certainty scores (4 or 5) in 21 of the 28 patients with appendicitis (75%) and lower scores (1 or 2) in five of the seven patients without appendicitis (71%) (AUC = 0.90; p = 0.001). CONCLUSION Standardized reporting and grading of objective imaging findings correlated well with postoperative pathology and may decrease the number of CT findings reported as indeterminate for appendicitis. Prospective evaluation of this reporting system on a cohort of patients with clinically suspected appendicitis is currently under way. PMID:26001230

Are UK radiologists satisfied with the training and support received in suspected child abuse?

International Nuclear Information System (INIS)

Leung, R.S.; Nwachuckwu, C.; Pervaiz, A.; Wallace, C.; Landes, C.; Offiah, A.C.

2009-01-01

Aim: To determine current practice and perceptions of the adequacy of training and support received for the reporting of skeletal surveys in suspected physical child abuse. Materials and methods: A list of telephone numbers of UK hospitals with a radiology department was obtained from Royal College of Radiologists. One hundred hospitals were then randomly selected for inclusion in the survey. An 18-item questionnaire was successfully administered to consultant radiologists from 84 departments. Results: Sixty-one percent of departments had a named radiologist to report their skeletal surveys, 16% assigned surveys to a random radiologist, and 23% referred them elsewhere. Only 52% of departments had a dedicated paediatric radiologist, thus in a significant proportion of departments (25%) initial reports on skeletal surveys for physical abuse were provided by non-paediatric radiologists. Fifteen percent did not have ready access to a paediatric radiology opinion. Sixty-one percent thought that the service could be improved. Expert evidence was provided by 5% of respondents. Seventy-three percent would never consider providing expert evidence, even if given adequate radiology and/or legal training. Conclusion: The survey shows significant dissatisfaction amongst consultant radiologists with the current service, confirms a low number of paediatric radiologists taking on this work, and suggests the potential to increase numbers of radiology child abuse experts by 27% if given improved training and support. Appropriate service and education strategies should be implemented.

Are UK radiologists satisfied with the training and support received in suspected child abuse?

Energy Technology Data Exchange (ETDEWEB)

Leung, R.S. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom); Nwachuckwu, C. [Department of Paediatrics, Whipps Cross Hospital, London (United Kingdom); Pervaiz, A. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom); Wallace, C.; Landes, C. [Department of Radiology, Royal Liverpool Childrens NHS Trust, Liverpool (United Kingdom); Offiah, A.C. [Department of Radiology, Great Ormond Street Hospital for Children, London (United Kingdom)], E-mail: OffiaA@gosh.nhs.uk

2009-07-15

Aim: To determine current practice and perceptions of the adequacy of training and support received for the reporting of skeletal surveys in suspected physical child abuse. Materials and methods: A list of telephone numbers of UK hospitals with a radiology department was obtained from Royal College of Radiologists. One hundred hospitals were then randomly selected for inclusion in the survey. An 18-item questionnaire was successfully administered to consultant radiologists from 84 departments. Results: Sixty-one percent of departments had a named radiologist to report their skeletal surveys, 16% assigned surveys to a random radiologist, and 23% referred them elsewhere. Only 52% of departments had a dedicated paediatric radiologist, thus in a significant proportion of departments (25%) initial reports on skeletal surveys for physical abuse were provided by non-paediatric radiologists. Fifteen percent did not have ready access to a paediatric radiology opinion. Sixty-one percent thought that the service could be improved. Expert evidence was provided by 5% of respondents. Seventy-three percent would never consider providing expert evidence, even if given adequate radiology and/or legal training. Conclusion: The survey shows significant dissatisfaction amongst consultant radiologists with the current service, confirms a low number of paediatric radiologists taking on this work, and suggests the potential to increase numbers of radiology child abuse experts by 27% if given improved training and support. Appropriate service and education strategies should be implemented.

Computer-aided detection (CAD) in mammography: Does it help the junior or the senior radiologist?

International Nuclear Information System (INIS)

Balleyguier, Corinne; Kinkel, Karen; Fermanian, Jacques; Malan, Sebastien; Djen, Germaine; Taourel, Patrice; Helenon, Olivier

2005-01-01

Objectives: To evaluate the impact of a computer-aided detection (CAD) system on the ability of a junior and senior radiologist to detect breast cancers on mammograms, and to determine the potential of CAD as a teaching tool in mammography. Methods: Hundred biopsy-proven cancers and 100 normal mammograms were randomly analyzed by a CAD system. The sensitivity (Se) and specificity (Sp) of the CAD system were calculated. In the second phase, to simulate daily practice, 110 mammograms (97 normal or with benign lesions, and 13 cancers) were examined independently by a junior and a senior radiologist, with and without CAD. Interpretations were standardized according to BI-RADS classification. Sensitivity, Specificity, positive and negative predictive values (PPV, NPV) were calculated for each session. Results: For the senior radiologist, Se slightly improved from 76.9 to 84.6% after CAD analysis (NS) (one case of clustered microcalcifications case overlooked by the senior radiologist was detected by CAD). Sp, PPV and PNV did not change significantly. For the junior radiologist, Se improved from 61.9 to 84.6% (significant change). Three cancers overlooked by the junior radiologist were detected by CAD. Sp was unchanged. Conclusion: CAD mammography proved more useful for the junior than for the senior radiologist, improving sensitivity. The CAD system may represent a useful educational tool for mammography

Diagnostic accuracy of surface coil MRI in assessing cartilaginous invasion in laryngeal tumours. Do we need contrast-agent administration?

International Nuclear Information System (INIS)

Preda, Lorenzo; Conte, Giorgio; Bonello, Luke; Giannitto, Caterina; Tagliabue, Elena; Raimondi, Sara; Ansarin, Mohssen; De Benedetto, Luigi; Cattaneo, Augusto; Maffini, Fausto; Bellomi, Massimo

2017-01-01

To assess the diagnostic accuracy of MRI performed using surface coils, with and without contrast medium, in predicting thyroid and cricoid cartilage infiltration in laryngeal tumours, and to investigate whether the radiologist's experience influences diagnostic accuracy. We retrospectively enrolled patients with biopsy-proven laryngeal cancer who had undergone preoperative staging MRI and open surgery. Two radiologists with different experience (senior vs. junior) reviewed the MR images without (session A1) and with contrast medium (session A2) separately. We calculated the accuracy of MRI with and without contrast medium in detecting infiltration of the thyroid and cricoid cartilages. Interobserver agreement was calculated by Cohen's Kappa (k). Forty-two patients were enrolled, for a total of 62 cartilages. In session A1 the senior and junior radiologists showed an accuracy of 85% and 71%, respectively, with k = 0.53 (0.33-0.72). In session A2 the senior and junior radiologists showed an accuracy of 84% and 77%, respectively, with k = 0.68 (0.49-0.86). Staging of laryngeal tumours with surface coil MRI showed good diagnostic accuracy in assessing cartilaginous infiltration. We observed similar values of diagnostic accuracy for the analysis performed with and without contrast medium for the senior radiologist. (orig.)

Diagnostic accuracy of surface coil MRI in assessing cartilaginous invasion in laryngeal tumours. Do we need contrast-agent administration?

Energy Technology Data Exchange (ETDEWEB)

Preda, Lorenzo [Universita degli Studi di Pavia, Department of Clinical-Surgical Diagnostic and Pediatric Sciences, Pavia (Italy); Division of Radiology, National Center of Oncological Hadrontherapy (CNAO Foundation), Pavia (Italy); Conte, Giorgio [Universita degli Studi di Milano, Postgraduation School in Radiodiagnostics, Milan (Italy); Bonello, Luke [Division of Radiology, Poliambulanza Hospital, Brescia (Italy); Giannitto, Caterina [European Institute of Oncology, Division of Radiology, Milan (Italy); Tagliabue, Elena; Raimondi, Sara [European Institute of Oncology, Division of Epidemiology and Biostatistics, Milan (Italy); Ansarin, Mohssen; De Benedetto, Luigi; Cattaneo, Augusto [European Institute of Oncology, Division of Head and Neck Surgery, Milan (Italy); Maffini, Fausto [European Institute of Oncology, Division of Pathology, Milan (Italy); Bellomi, Massimo [European Institute of Oncology, Division of Radiology, Milan (Italy); Universita degli Studi di Milano, Oncology and Haematology/Oncology Department, Milan (Italy)

2017-11-15

To assess the diagnostic accuracy of MRI performed using surface coils, with and without contrast medium, in predicting thyroid and cricoid cartilage infiltration in laryngeal tumours, and to investigate whether the radiologist's experience influences diagnostic accuracy. We retrospectively enrolled patients with biopsy-proven laryngeal cancer who had undergone preoperative staging MRI and open surgery. Two radiologists with different experience (senior vs. junior) reviewed the MR images without (session A1) and with contrast medium (session A2) separately. We calculated the accuracy of MRI with and without contrast medium in detecting infiltration of the thyroid and cricoid cartilages. Interobserver agreement was calculated by Cohen's Kappa (k). Forty-two patients were enrolled, for a total of 62 cartilages. In session A1 the senior and junior radiologists showed an accuracy of 85% and 71%, respectively, with k = 0.53 (0.33-0.72). In session A2 the senior and junior radiologists showed an accuracy of 84% and 77%, respectively, with k = 0.68 (0.49-0.86). Staging of laryngeal tumours with surface coil MRI showed good diagnostic accuracy in assessing cartilaginous infiltration. We observed similar values of diagnostic accuracy for the analysis performed with and without contrast medium for the senior radiologist. (orig.)

Audiovisual biofeedback improves motion prediction accuracy.

Science.gov (United States)

Pollock, Sean; Lee, Danny; Keall, Paul; Kim, Taeho

2013-04-01

The accuracy of motion prediction, utilized to overcome the system latency of motion management radiotherapy systems, is hampered by irregularities present in the patients' respiratory pattern. Audiovisual (AV) biofeedback has been shown to reduce respiratory irregularities. The aim of this study was to test the hypothesis that AV biofeedback improves the accuracy of motion prediction. An AV biofeedback system combined with real-time respiratory data acquisition and MR images were implemented in this project. One-dimensional respiratory data from (1) the abdominal wall (30 Hz) and (2) the thoracic diaphragm (5 Hz) were obtained from 15 healthy human subjects across 30 studies. The subjects were required to breathe with and without the guidance of AV biofeedback during each study. The obtained respiratory signals were then implemented in a kernel density estimation prediction algorithm. For each of the 30 studies, five different prediction times ranging from 50 to 1400 ms were tested (150 predictions performed). Prediction error was quantified as the root mean square error (RMSE); the RMSE was calculated from the difference between the real and predicted respiratory data. The statistical significance of the prediction results was determined by the Student's t-test. Prediction accuracy was considerably improved by the implementation of AV biofeedback. Of the 150 respiratory predictions performed, prediction accuracy was improved 69% (103/150) of the time for abdominal wall data, and 78% (117/150) of the time for diaphragm data. The average reduction in RMSE due to AV biofeedback over unguided respiration was 26% (p biofeedback improves prediction accuracy. This would result in increased efficiency of motion management techniques affected by system latencies used in radiotherapy.

The internet for radiologists

International Nuclear Information System (INIS)

Caramella, D.; Pavone, P.

1999-01-01

This book provides information on all aspects of the Internet of interest to radiologists. It also provides non-experts with all the information necessary to profit from the Internet and to explore the different possibilities offered by the www. Its use should be recommended to all radiologists who use the Internet. (orig.)

X-rays taken by radiologists. Influence on a continuous quality improvement process?

International Nuclear Information System (INIS)

Kurtz, C.; Freiburg Univ.; Czapp, W.; Trampe, I.; Leppek, R.; Klose, K.J.

2000-01-01

Purpose: To evaluate how the training of radiology residents in taking radiographs influences the work of radiographers and the established quality standards. Methods: A first year radiology resident was trained for 4 weeks in focusing and exposure techniques by radiographers. In a second period the resident took 582 radiograms, which were compared with those taken by technicians for error estimation on a daily basis. During a third period the radiographs were produced in a contest between the resident and a skilled radiographer. Errors were analysed by two independent experts according to established guidelines of the German Medical Association. Results: At the beginning of the second period the average error rate of the resident was 11.9% as compared to 8.9% in the technicians team, in the following month 9.2% versus 15.9%. In the third period no relevant difference in errors could be observed. Finally, unexpected quality improvements were implemented like an improved standardization of focusing and exposure techniques as well as dose reduction. Conclusions: Radiology residents easily learn focusing and exposure techniques and achieve comparable results as radiographers within a short period of time. The additionally achieved knowledge improves the technical process of taking radiographs. We recommend to include a two plane radiography training period in the curriculum of radiology residents. It reinforces the radiologist's role in continuous quality improvements of the diagnostic process. (orig.) [de

Improving shuffler assay accuracy

International Nuclear Information System (INIS)

Rinard, P.M.

1995-01-01

Drums of uranium waste should be disposed of in an economical and environmentally sound manner. The most accurate possible assays of the uranium masses in the drums are required for proper disposal. The accuracies of assays from a shuffler are affected by the type of matrix material in the drums. Non-hydrogenous matrices have little effect on neutron transport and accuracies are very good. If self-shielding is known to be a minor problem, good accuracies are also obtained with hydrogenous matrices when a polyethylene sleeve is placed around the drums. But for those cases where self-shielding may be a problem, matrices are hydrogenous, and uranium distributions are non-uniform throughout the drums, the accuracies are degraded. They can be greatly improved by determining the distributions of the uranium and then applying correction factors based on the distributions. This paper describes a technique for determining uranium distributions by using the neutron count rates in detector banks around the waste drum and solving a set of overdetermined linear equations. Other approaches were studied to determine the distributions and are described briefly. Implementation of this correction is anticipated on an existing shuffler next year

HOW DO RADIOLOGISTS USE THE HUMAN SEARCH ENGINE?

Science.gov (United States)

Wolfe, Jeremy M.; Evans, Karla K.; Drew, Trafton; Aizenman, Avigael; Josephs, Emilie

2016-01-01

Radiologists perform many ‘visual search tasks’ in which they look for one or more instances of one or more types of target item in a medical image (e.g. cancer screening). To understand and improve how radiologists do such tasks, it must be understood how the human ‘search engine’ works. This article briefly reviews some of the relevant work into this aspect of medical image perception. Questions include how attention and the eyes are guided in radiologic search? How is global (image-wide) information used in search? How might properties of human vision and human cognition lead to errors in radiologic search? PMID:26656078

How do radiologists use the human search engine?

International Nuclear Information System (INIS)

Wolfe, Jeremy M.; Evans, Karla K.; Drew, Trafton; Aizenman, Avigael; Josephs, Emilie

2016-01-01

Radiologists perform many 'visual search tasks' in which they look for one or more instances of one or more types of target item in a medical image (e.g. cancer screening). To understand and improve how radiologists do such tasks, it must be understood how the human 'search engine' works. This article briefly reviews some of the relevant work into this aspect of medical image perception. Questions include how attention and the eyes are guided in radiologic search? How is global (image-wide) information used in search? How might properties of human vision and human cognition lead to errors in radiologic search? (authors)

Improving coding accuracy in an academic practice.

Science.gov (United States)

Nguyen, Dana; O'Mara, Heather; Powell, Robert

2017-01-01

Practice management has become an increasingly important component of graduate medical education. This applies to every practice environment; private, academic, and military. One of the most critical aspects of practice management is documentation and coding for physician services, as they directly affect the financial success of any practice. Our quality improvement project aimed to implement a new and innovative method for teaching billing and coding in a longitudinal fashion in a family medicine residency. We hypothesized that implementation of a new teaching strategy would increase coding accuracy rates among residents and faculty. Design: single group, pretest-posttest. military family medicine residency clinic. Study populations: 7 faculty physicians and 18 resident physicians participated as learners in the project. Educational intervention: monthly structured coding learning sessions in the academic curriculum that involved learner-presented cases, small group case review, and large group discussion. overall coding accuracy (compliance) percentage and coding accuracy per year group for the subjects that were able to participate longitudinally. Statistical tests used: average coding accuracy for population; paired t test to assess improvement between 2 intervention periods, both aggregate and by year group. Overall coding accuracy rates remained stable over the course of time regardless of the modality of the educational intervention. A paired t test was conducted to compare coding accuracy rates at baseline (mean (M)=26.4%, SD=10%) to accuracy rates after all educational interventions were complete (M=26.8%, SD=12%); t24=-0.127, P=.90. Didactic teaching and small group discussion sessions did not improve overall coding accuracy in a residency practice. Future interventions could focus on educating providers at the individual level.

How Radiologists Think: Understanding Fast and Slow Thought Processing and How It Can Improve Our Teaching.

Science.gov (United States)

van der Gijp, Anouk; Webb, Emily M; Naeger, David M

2017-06-01

Scholars have identified two distinct ways of thinking. This "Dual Process Theory" distinguishes a fast, nonanalytical way of thinking, called "System 1," and a slow, analytical way of thinking, referred to as "System 2." In radiology, we use both methods when interpreting and reporting images, and both should ideally be emphasized when educating our trainees. This review provides practical tips for improving radiology education, by enhancing System 1 and System 2 thinking among our trainees. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Can we improve accuracy and reliability of MRI interpretation in children with optic pathway glioma? Proposal for a reproducible imaging classification

Energy Technology Data Exchange (ETDEWEB)

Lambron, Julien; Frampas, Eric; Toulgoat, Frederique [University Hospital, Department of Radiology, Nantes (France); Rakotonjanahary, Josue [University Hospital, Department of Pediatric Oncology, Angers (France); University Paris Diderot, INSERM CIE5 Robert Debre Hospital, Assistance Publique-Hopitaux de Paris (AP-HP), Paris (France); Loisel, Didier [University Hospital, Department of Radiology, Angers (France); Carli, Emilie de; Rialland, Xavier [University Hospital, Department of Pediatric Oncology, Angers (France); Delion, Matthieu [University Hospital, Department of Neurosurgery, Angers (France)

2016-02-15

Magnetic resonance (MR) images from children with optic pathway glioma (OPG) are complex. We initiated this study to evaluate the accuracy of MR imaging (MRI) interpretation and to propose a simple and reproducible imaging classification for MRI. We randomly selected 140 MRIs from among 510 MRIs performed on 104 children diagnosed with OPG in France from 1990 to 2004. These images were reviewed independently by three radiologists (F.T., 15 years of experience in neuroradiology; D.L., 25 years of experience in pediatric radiology; and J.L., 3 years of experience in radiology) using a classification derived from the Dodge and modified Dodge classifications. Intra- and interobserver reliabilities were assessed using the Bland-Altman method and the kappa coefficient. These reviews allowed the definition of reliable criteria for MRI interpretation. The reviews showed intraobserver variability and large discrepancies among the three radiologists (kappa coefficient varying from 0.11 to 1). These variabilities were too large for the interpretation to be considered reproducible over time or among observers. A consensual analysis, taking into account all observed variabilities, allowed the development of a definitive interpretation protocol. Using this revised protocol, we observed consistent intra- and interobserver results (kappa coefficient varying from 0.56 to 1). The mean interobserver difference for the solid portion of the tumor with contrast enhancement was 0.8 cm{sup 3} (limits of agreement = -16 to 17). We propose simple and precise rules for improving the accuracy and reliability of MRI interpretation for children with OPG. Further studies will be necessary to investigate the possible prognostic value of this approach. (orig.)

Systematic Layout Planning of a Radiology Reporting Area to Optimize Radiologists' Performance.

Science.gov (United States)

Benitez, Guilherme Brittes; Fogliatto, Flavio Sanson; Cardoso, Ricardo Bertoglio; Torres, Felipe Soares; Faccin, Carlo Sasso; Dora, José Miguel

2018-04-01

Optimizing radiologists' performance is a major priority for managers of health services/systems, since the radiologists' reporting activity imposes a severe constraint on radiology productivity. Despite that, methods to optimize radiologists' reporting workplace layout are scarce in the literature. This study was performed in the Radiology Division (RD) of an 850-bed University-based general hospital. The analysis of the reporting workplace layout was carried out using the systematic layout planning (SLP) method, in association with cluster analysis as a complementary tool in early stages of SLP. Radiologists, architects, and hospital managers were the stakeholders consulted for the completion of different stages of the layout planning process. A step-by-step description of the proposed methodology to plan an RD reporting layout is presented. Clusters of radiologists were defined using types of exams reported and their frequency of occurrence as clustering variables. Sectors with high degree of interaction were placed in proximity in the new RD layout, with separation of noisy and quiet areas. Four reporting cells were positioned in the quiet area, grouping radiologists by subspecialty, as follows: cluster 1-abdomen; cluster 2-musculoskeletal; cluster 3-neurological, vascular and head & neck; cluster 4-thoracic and cardiac. The creation of reporting cells has the potential to limit unplanned interruptions and enhance the exchange of knowledge and information within cells, joining radiologists with the same expertise. That should lead to improvements in productivity, allowing managers to more easily monitor radiologists' performance.

Radiologist perceptions of radiographer role development in Scotland

Energy Technology Data Exchange (ETDEWEB)

Forsyth, Lesley J. [School of Health Sciences, Robert Gordon University, Faculty of Health and Social Care, Garthdee Road, Garthdee, Aberdeen AB10 7QG (United Kingdom)]. E-mail: l.forsyth@rgu.ac.uk; Robertson, Elizabeth M. [Department of Radiology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZN (United Kingdom)]. E-mail: e.m.robertson@arh.grampian.scot.nhs.uk

2007-02-15

Aim: To survey the perceptions of the Scottish radiology community in relation to radiographer role development. Methods: A postal questionnaire was sent to all consultant radiologists recorded on the NHS Scotland database of consultants. Results: Response rate was 63%. (i) Respondents considered increased professional standing of radiographers, best use of manpower resources, reduced pressure on the service and improved recruitment and retention, as positive advantages of radiographer development. (ii) The potential impact on radiology specialist registrar training, lack of clear medico-legal responsibilities and radiographers recognising the limitations of their abilities were identified as the main areas of radiologist anxiety. (iii) Fifty-seven percent did not consider current post-registration radiography education and training resources adequate to underpin the requirement of developed roles. (iv) Barriers to radiographer development were identified as lack of radiography and radiology staff, suitable education, financial constraints, traditional views and resistance to change. (v) Eighty-two percent reported support for radiographer role development and willingness to participate actively in developments. Conclusion: Despite reservations Scottish radiologists are supportive of the development of radiography colleagues, however, guidance is required on the medico-legal and accountability aspects of radiographers assuming new roles. Radiologist involvement in education and training for new roles may increase their confidence and trust in radiographers to work within the limitations of their competency and training.

Radiologist perceptions of radiographer role development in Scotland

International Nuclear Information System (INIS)

Forsyth, Lesley J.; Robertson, Elizabeth M.

2007-01-01

Aim: To survey the perceptions of the Scottish radiology community in relation to radiographer role development. Methods: A postal questionnaire was sent to all consultant radiologists recorded on the NHS Scotland database of consultants. Results: Response rate was 63%. (i) Respondents considered increased professional standing of radiographers, best use of manpower resources, reduced pressure on the service and improved recruitment and retention, as positive advantages of radiographer development. (ii) The potential impact on radiology specialist registrar training, lack of clear medico-legal responsibilities and radiographers recognising the limitations of their abilities were identified as the main areas of radiologist anxiety. (iii) Fifty-seven percent did not consider current post-registration radiography education and training resources adequate to underpin the requirement of developed roles. (iv) Barriers to radiographer development were identified as lack of radiography and radiology staff, suitable education, financial constraints, traditional views and resistance to change. (v) Eighty-two percent reported support for radiographer role development and willingness to participate actively in developments. Conclusion: Despite reservations Scottish radiologists are supportive of the development of radiography colleagues, however, guidance is required on the medico-legal and accountability aspects of radiographers assuming new roles. Radiologist involvement in education and training for new roles may increase their confidence and trust in radiographers to work within the limitations of their competency and training

Acute abdominal emergencies: What radiologist have to know

International Nuclear Information System (INIS)

Nedevska, M.

2015-01-01

Full text: Acute abdominal pathology is an important cause of emergency admissions, generally putting pressure to obtain a quick and correct diagnosis. This may lead to the simultaneous use of concurrent imaging techniques, where the diagnostic accuracy may be operator dependent. It is important to the radiologist to understand how, when and why medical imaging should be used for each clinical context under appreciation. Imaging protocols should be optimally set in order not to miss the most important, bur subtle diagnostic signs. Radiologist should be conversant in all aspects of this emergency situation including the ability to provide minimally invasive treatment option, such as access drainage or vascular embolization. Although multidetector computed tomography is considered the workhorse in the diagnostic management, imaging alternatives must be kept in mind, especially tailored to the available equipment and the experience of the investigator team. Learning objectives: to describe the advantages and shortcomings of the different imaging techniques; to understand the value of the diagnostic information and the way this can change patient management; to describe and propose an effective diagnostic imaging strategy for the assessment of acute abdominal pain

Diagnostic Accuracy of MRI Versus CT for the Evaluation of Acute Appendicitis in Children and Young Adults.

Science.gov (United States)

Kinner, Sonja; Pickhardt, Perry J; Riedesel, Erica L; Gill, Kara G; Robbins, Jessica B; Kitchin, Douglas R; Ziemlewicz, Timothy J; Harringa, John B; Reeder, Scott B; Repplinger, Michael D

2017-10-01

Appendicitis is frequently diagnosed in the emergency department, most commonly using CT. The purpose of this study was to compare the diagnostic accuracy of contrast-enhanced MRI with that of contrast-enhanced CT for the diagnosis of appendicitis in adolescents when interpreted by abdominal radiologists and pediatric radiologists. Our study included a prospectively enrolled cohort of 48 patients (12-20 years old) with nontraumatic abdominal pain who underwent CT and MRI. Fellowship-trained abdominal and pediatric radiologists reviewed all CT and MRI studies in randomized order, blinded to patient outcome. Likelihood for appendicitis was rated on a 5-point scale (1, definitely not appendicitis; 5, definitely appendicitis) for CT, the unenhanced portion of the MRI, and the entire contrast-enhanced MRI study. ROC curves were generated and AUC compared for each scan type for all six readers and then stratified by radiologist type. Image test characteristics, interrater reliability, and reading times were compared. Sensitivity and specificity were 85.9% (95% CI, 76.2-92.7%) and 93.8% (95% CI, 89.7-96.7%) for unenhanced MRI, 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for contrast-enhanced MRI, and 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for CT. No difference was found in the diagnostic accuracy or interpretation time when comparing abdominal radiologists to pediatric radiologists (CT, 3.0 min vs 2.8 min; contrast-enhanced MRI, 2.4 min vs 1.8 min; unenhanced MRI, 1.5 min vs 2.3 min). Substantial agreement between abdominal and pediatric radiologists was seen for all methods (κ = 0.72-0.83). The diagnostic accuracy of MRI to diagnose appendicitis was very similar to CT. No statistically significant difference in accuracy was observed between imaging modality or radiologist subspecialty.

The radiologist as defendant

International Nuclear Information System (INIS)

Bundy, A.L.; James, A.E. Jr.

1988-01-01

As the diagnostic radiologist has evolved through medical history, his role has changed from one of a technical expert to that of a respected part of the medical team, possessing extraordinary knowledge and skills in use of the most expensive and complex instrumentation in the health care delivery system. The rapid advances in radiological technology and instrumentation have enabled radiologists to assume a more primary role in medical care. Subspecialties such as ultrasound, computed tomography, digital radiography, and magnetic resonance imaging have emerged over the past decade as invaluable resources in medical diagnosis, and the radiologist, as the expert in these fields, has moved into view. As he assumes his rapidly evolving role, so too must he be prepared to bear the legal pressures that will most likely increase in proportion to the technical advances, as well as his changing role

Radiologists' knowledge and perceptions of the impact of contrast-induced nephropathy and its risk factors when performing computed tomography examinations: A survey of European radiologists

International Nuclear Information System (INIS)

Reddan, Donal; Fishman, Elliot K.

2008-01-01

Background: The past decade has seen a proliferation in the number of CT procedures. As increasing numbers of elderly patients with multiple comorbidities undergo contrast media (CM)-enhanced procedures, more patients are at risk for contrast-induced nephropathy (CIN). Objectives: To understand whether radiologists are sufficiently aware of the incidence, impact and risk factors of CIN, and whether they are taking sufficient measures to prevent CIN among patients undergoing CT. Materials and methods: A telephone or online survey was conducted in 2005 with 509 radiologists from 10 European countries. Participants had a minimum of 3 years' experience and performed at least 50 CT scans per week. Results: Most (88%) radiologists believed that CIN is an important issue. While 45% identify that a patient is experiencing CIN when the serum creatinine level increases >25% (0.5 mg/dL) from baseline within 48 h, the remainder used criteria that might lead to significant under-diagnosis. Most (72%) radiologists believed that CIN is associated with increased morbidity; 56% did not believe that it is associated with increased mortality. Most respondents agreed that pre-existing renal impairment (97%), dehydration (90%) and diabetes (89%) were risk factors for CIN; however, 26%, 30% and 46%, respectively, did not identify advanced age, CM dose or congestive cardiac failure as risk factors. Only 7% of radiologists thought they were always made aware of CIN associated with their cases and 28% never consulted a nephrologist to discuss patients at risk of CIN or who had developed CIN. Conclusion: There is highly variable awareness of the definition, impact and risk factors for CIN among European radiologists. Data regarding the importance of CIN in CT are limited. Improved efforts are required to better educate radiologists and referring physicians and to institute appropriate protocols to identify at-risk patients and prevent CIN

Evaluation of the efficacy of the guideline on reading CT images of malignant pleural mesothelioma with reference CT films for improving the proficiency of radiologists

Energy Technology Data Exchange (ETDEWEB)

Zhou, Huashi, E-mail: zhouhua@u-fukui.ac.jp [Department of Environmental Health, School of Medicine University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture, 910-1193 (Japan); Tamura, Taro, E-mail: tarou@u-fukui.ac.jp [Department of Environmental Health, School of Medicine University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture, 910-1193 (Japan); Kusaka, Yukinori, E-mail: kusakayk@gmail.com [Department of Environmental Health, School of Medicine University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture, 910-1193 (Japan); Suganuma, Narufumi, E-mail: nsuganuma@kochi-u.ac.jp [Department of Environmental Medicine, Kochi University School of Medicine (Japan); Subhannachart, Ponglada, E-mail: pongladas@gmail.com [Central Chest Disease Institute of Thailand, 39 Moo 9, Tiwanon Road, Muang Nonthaburi, 11000 (Thailand); Vijitsanguan, Chomphunut, E-mail: Chompoo_vj@yahoo.com [Central Chest Disease Institute of Thailand, 39 Moo 9, Tiwanon Road, Muang Nonthaburi, 11000 (Thailand); Noisiri, Weeraya, E-mail: weeraya_tat@yahoo.com [Central Chest Disease Institute of Thailand, 39 Moo 9, Tiwanon Road, Muang Nonthaburi, 11000 (Thailand); Hering, Kurt G., E-mail: k.g.hering@t-online.de [Department of Diagnostic Radiology, Radiooncology and Nuclear Medicine, Radiological Clinic, Miner' s Hospital, Radiologische Klinik, Lansppaschaftskranhaus Dortmund, Wieckesweg 27, 44309, Dortmund (Germany); Akira, Masanori, E-mail: akira@kch.hosp.go.jp [Department of Radiology, National Hospital Organization Kinki-Chuo Chest Medical Center, 1180 Nagasone-cho, Kita-ku, Sakai, Osaka, 591-8555 (Japan); Itoh, Harumi, E-mail: hitoh@fmsrsa.fukui-med.ac.jp [Department of Environmental Health, School of Medicine University of Fukui, 23-3 Shimoaitsuki, Matsuoka, Eihezi-cho, Fukui Prefecture, 910-1193 (Japan); Department of Radiology, School of Medicine, University of Fukui, 23-3 Shimoaitsuki Matsuoka, Eiheizi-cho, Fukui Prefecture, 910-1193 (Japan); and others

2013-01-15

Purpose: To assess the efficacy of the developed guideline on reading CT images of malignant pleural mesothelioma for improving radiologists’ reading proficiency. Materials and Methods: Three radiologists independently read the CT films of 22 cases including definite mesothelioma and non-mesothelioma cases at two times before and after studying the malignant pleural mesothelioma CT Guideline. The sensitivity and specificity for mesothelioma were calculated and compared between the 1st and 2nd trials. The kappa statistics was examined for agreement with experts for mesothelioma probability and for mesothelioma features recorded by three radiologists. Results: After studying the mesothelioma CT Guideline, the sensitivity for mesothelioma shown by the three radiologists at the 2nd trial was 100%, 100% and 80%, which were higher than 80%, 85% and 60% at the 1st trial, respectively. The average kappa for agreement between radiologists and experts on dichotomized mesothelioma probability were 0.69 (good) at the 2nd trial vs. 0.38 (fair) at the 1st trial. The average kappa for the agreement with experts for each of 7 features by three radiologists were 0.52–0.80 at the 2nd trial, which were significantly higher than 0.34–0.58 at the 1st trial (Wilcoxon Signed Rank Test: P < 0.01), and as to five features “unilateral pleural effusion”, “nodular pleural thickening”, “tumoral encasement of lung”, “mediastinal pleural thickening”, and “diminished lung”, they achieved good agreement with average kappa of 0.61–0.80. Conclusion: The developed mesothelioma CT Guideline was suggested to have substantial effect in improving the radiologists’ proficiency for reading CT images of mesothelioma, and may contribute to accurate diagnosis of mesothelioma.

Evaluation of the efficacy of the guideline on reading CT images of malignant pleural mesothelioma with reference CT films for improving the proficiency of radiologists

International Nuclear Information System (INIS)

Zhou, Huashi; Tamura, Taro; Kusaka, Yukinori; Suganuma, Narufumi; Subhannachart, Ponglada; Vijitsanguan, Chomphunut; Noisiri, Weeraya; Hering, Kurt G.; Akira, Masanori; Itoh, Harumi

2013-01-01

Purpose: To assess the efficacy of the developed guideline on reading CT images of malignant pleural mesothelioma for improving radiologists’ reading proficiency. Materials and Methods: Three radiologists independently read the CT films of 22 cases including definite mesothelioma and non-mesothelioma cases at two times before and after studying the malignant pleural mesothelioma CT Guideline. The sensitivity and specificity for mesothelioma were calculated and compared between the 1st and 2nd trials. The kappa statistics was examined for agreement with experts for mesothelioma probability and for mesothelioma features recorded by three radiologists. Results: After studying the mesothelioma CT Guideline, the sensitivity for mesothelioma shown by the three radiologists at the 2nd trial was 100%, 100% and 80%, which were higher than 80%, 85% and 60% at the 1st trial, respectively. The average kappa for agreement between radiologists and experts on dichotomized mesothelioma probability were 0.69 (good) at the 2nd trial vs. 0.38 (fair) at the 1st trial. The average kappa for the agreement with experts for each of 7 features by three radiologists were 0.52–0.80 at the 2nd trial, which were significantly higher than 0.34–0.58 at the 1st trial (Wilcoxon Signed Rank Test: P < 0.01), and as to five features “unilateral pleural effusion”, “nodular pleural thickening”, “tumoral encasement of lung”, “mediastinal pleural thickening”, and “diminished lung”, they achieved good agreement with average kappa of 0.61–0.80. Conclusion: The developed mesothelioma CT Guideline was suggested to have substantial effect in improving the radiologists’ proficiency for reading CT images of mesothelioma, and may contribute to accurate diagnosis of mesothelioma

Job stress and satisfaction among clinical radiologists

International Nuclear Information System (INIS)

Graham, J.; Ramirez, A.J.; Field, S.; Richards, M.A.

2000-01-01

AIMS: Consultant radiologists appear to be at greater risk of burnout than consultants working in other specialties. The aim of this study was to examine sources of stress and satisfaction at work for radiologists and hospital consultants in other specialties in order to try to understand this difference. MATERIALS AND METHODS: A postal questionnaire survey of psychiatric morbidity (12-item General Health Questionnaire), burnout (Maslach Burnout Inventory) and sources of job stress and satisfaction (study-specific questionnaires) was carried out among a random sample of 882 hospital consultants working in radiology and three other specialties (surgery, gastroenterology and oncology). RESULTS: The most stressful aspect of work for radiologists was work overload. Inadequacies in current staffing and facilities and concerns about funding were also major sources of stress, as were impositions made on radiologists by other clinicians. The most important sources of satisfaction for radiologists were their relationships with patients and being perceived to do their job well by colleagues. Importantly, radiologists reported less satisfaction than the other specialists from many of the aspects of work measured. A greater proportion of radiologists than other specialists felt insufficiently trained in communication skills [80% (n = 168) vs 47% (n = 310);P < 0.001] and management skills [84% (n = 179) vs 76% (n = 506);P < 0.05]. CONCLUSION: These data highlight aspects of radiologists' work which need to be tackled in order to reduce their stress and increase their satisfaction, and thereby their risk of burnout. Graham, J. (2000)

HOW DO RADIOLOGISTS USE THE HUMAN SEARCH ENGINE?

Science.gov (United States)

Wolfe, Jeremy M; Evans, Karla K; Drew, Trafton; Aizenman, Avigael; Josephs, Emilie

2016-06-01

Radiologists perform many 'visual search tasks' in which they look for one or more instances of one or more types of target item in a medical image (e.g. cancer screening). To understand and improve how radiologists do such tasks, it must be understood how the human 'search engine' works. This article briefly reviews some of the relevant work into this aspect of medical image perception. Questions include how attention and the eyes are guided in radiologic search? How is global (image-wide) information used in search? How might properties of human vision and human cognition lead to errors in radiologic search? © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Radiographic Union Score for Hip (RUSH): the use of a checklist to evaluate hip fracture healing improves agreement between radiologists and orthopedic surgeons

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Chiavaras, Mary M. [McMaster University, Department of Radiology, Hamilton, Ontario (Canada); Hamilton General Hospital, Department of Diagnostic Imaging, Hamilton, Ontario (Canada); Bains, Simrit [University of Western Ontario Medical School, London, Ontario (Canada); Choudur, Hema; Parasu, Naveen [McMaster University, Department of Radiology, Hamilton, Ontario (Canada); Jacobson, Jon [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Ayeni, Olufemi; Petrisor, Brad; Sprague, Sheila; Bhandari, Mohit [McMaster University, Department of Orthopedic Surgery, Hamilton, Ontario (Canada); Chakravertty, Rajesh [University of Toronto, Department of Orthopedic Surgery, Toronto, Ontario (Canada)

2013-08-15

The assessment of fracture healing following intertrochanteric fracture fixation is highly variable with no validated standards. Agreement with respect to fracture healing following surgery is important for optimal patient management. The purpose of this study was to (1) assess reliability of intertrochanteric fracture healing assessment and (2) determine if a novel radiographic scoring system for hip fractures improves agreement between radiologists and orthopedic surgeons. A panel of three radiologists and three orthopedic surgeons assessed fracture healing in 150 cases of intertrochanteric fractures at two separate time points to determine inter-rater and intra-rater agreement. Reviewers, blinded to the time after injury, first subjectively assessed overall healing using frontal and lateral radiographs for each patient at a single time point. Reviewers then scored each fracture using a Radiographic Union Score for Hip (RUSH) form to determine whether this improves agreement regarding hip fracture healing. Inter-rater agreement for the overall subjective impression of fracture healing between reviewer groups was only fair (intraclass coefficient [ICC] = 0.34, 95 % CI: 0.11-0.52). Use of the RUSH score improved overall agreement between groups to substantial (ICC = 0.66, 95 % CI: 0.53-0.75). Across reviewers, healing of the medial cortex and overall RUSH score itself demonstrated high correlations with overall perceptions of healing (r = 0.53 and r = 0.72, respectively).??The RUSH score improves agreement of fracture healing assessment between orthopedic surgeons and radiologists, offers a systematic approach to evaluating intertrochanteric hip fracture radiographs, and may ultimately provide prognostic information that could predict healing outcomes in patients with femoral neck fractures. (orig.)

The Radiographic Union Score for Hip (RUSH): the use of a checklist to evaluate hip fracture healing improves agreement between radiologists and orthopedic surgeons

International Nuclear Information System (INIS)

Chiavaras, Mary M.; Bains, Simrit; Choudur, Hema; Parasu, Naveen; Jacobson, Jon; Ayeni, Olufemi; Petrisor, Brad; Sprague, Sheila; Bhandari, Mohit; Chakravertty, Rajesh

2013-01-01

The assessment of fracture healing following intertrochanteric fracture fixation is highly variable with no validated standards. Agreement with respect to fracture healing following surgery is important for optimal patient management. The purpose of this study was to (1) assess reliability of intertrochanteric fracture healing assessment and (2) determine if a novel radiographic scoring system for hip fractures improves agreement between radiologists and orthopedic surgeons. A panel of three radiologists and three orthopedic surgeons assessed fracture healing in 150 cases of intertrochanteric fractures at two separate time points to determine inter-rater and intra-rater agreement. Reviewers, blinded to the time after injury, first subjectively assessed overall healing using frontal and lateral radiographs for each patient at a single time point. Reviewers then scored each fracture using a Radiographic Union Score for Hip (RUSH) form to determine whether this improves agreement regarding hip fracture healing. Inter-rater agreement for the overall subjective impression of fracture healing between reviewer groups was only fair (intraclass coefficient [ICC] = 0.34, 95 % CI: 0.11-0.52). Use of the RUSH score improved overall agreement between groups to substantial (ICC = 0.66, 95 % CI: 0.53-0.75). Across reviewers, healing of the medial cortex and overall RUSH score itself demonstrated high correlations with overall perceptions of healing (r = 0.53 and r = 0.72, respectively).??The RUSH score improves agreement of fracture healing assessment between orthopedic surgeons and radiologists, offers a systematic approach to evaluating intertrochanteric hip fracture radiographs, and may ultimately provide prognostic information that could predict healing outcomes in patients with femoral neck fractures. (orig.)

[Acceptance of medical apps and e‑books among German radiologists].

Science.gov (United States)

Schleder, S; Dendl, L M; Niessen, C; Stroszczynski, C; Schreyer, A G

2017-09-01

Smartphones, tablet PCs, mobile applications (apps) and electronic book files (e-books) affect our lives in private and job-related settings. The aim of this study was to analyze the behavior of radiologists on smartphones, tablet PCs and e‑books and to investigate its effect on their daily work. An online survey containing of 23 questions was conducted using Survey Monkey© ( www.surveymonkey.com ). The invitation to the survey was done using the newsletter of the German Radiological Society (DRG). The acquired data was automatically stored by the software and then analyzed using descriptive statistics. In total, 104 radiologists (29% female) participated in the online survey. Of these, 93% and 96.5% owned a smartphone or a tablet PC, respectively, and 72% and 67% used medical apps and e‑books, respectively. Through their use, 31% found moderate and 41% found enormous improvement in their daily work. A majority of participating radiologists would be willing to pay an increased user fee for optimized apps or e‑books. With currently only moderate individual benefit of mobile medical apps and e‑books, there is a widespread need for optimally configured apps and e‑books with a correspondingly high market potential. (1) Radiologists use smartphones (93%) or tablet PCs (96.5%); (2) 72% of radiologists use a smartphone or tablet PC for medical material; (3) 53% of radiologists report significant assistance from or a high value of the mobile medical applications used; (4) There is a willingness to pay a license fee for optimized mobile applications or e‑books.

Radiologists' knowledge and perceptions of the impact of contrast-induced nephropathy and its risk factors when performing computed tomography examinations: A survey of European radiologists

Energy Technology Data Exchange (ETDEWEB)

Reddan, Donal [University College Galway Hospitals, Unit 7, Merlin Park Hospital, Galway (Ireland)], E-mail: donal.reddan@mailn.hse.ie; Fishman, Elliot K. [Johns Hopkins Hospital, Baltimore, MD (United States)

2008-05-15

Background: The past decade has seen a proliferation in the number of CT procedures. As increasing numbers of elderly patients with multiple comorbidities undergo contrast media (CM)-enhanced procedures, more patients are at risk for contrast-induced nephropathy (CIN). Objectives: To understand whether radiologists are sufficiently aware of the incidence, impact and risk factors of CIN, and whether they are taking sufficient measures to prevent CIN among patients undergoing CT. Materials and methods: A telephone or online survey was conducted in 2005 with 509 radiologists from 10 European countries. Participants had a minimum of 3 years' experience and performed at least 50 CT scans per week. Results: Most (88%) radiologists believed that CIN is an important issue. While 45% identify that a patient is experiencing CIN when the serum creatinine level increases >25% (0.5 mg/dL) from baseline within 48 h, the remainder used criteria that might lead to significant under-diagnosis. Most (72%) radiologists believed that CIN is associated with increased morbidity; 56% did not believe that it is associated with increased mortality. Most respondents agreed that pre-existing renal impairment (97%), dehydration (90%) and diabetes (89%) were risk factors for CIN; however, 26%, 30% and 46%, respectively, did not identify advanced age, CM dose or congestive cardiac failure as risk factors. Only 7% of radiologists thought they were always made aware of CIN associated with their cases and 28% never consulted a nephrologist to discuss patients at risk of CIN or who had developed CIN. Conclusion: There is highly variable awareness of the definition, impact and risk factors for CIN among European radiologists. Data regarding the importance of CIN in CT are limited. Improved efforts are required to better educate radiologists and referring physicians and to institute appropriate protocols to identify at-risk patients and prevent CIN.

Accuracy of hepatocellular carcinoma detection on multidetector CT in a transplant liver population with explant liver correlation

International Nuclear Information System (INIS)

Addley, H.C.; Griffin, N.; Shaw, A.S.; Mannelli, L.; Parker, R.A.; Aitken, S.; Wood, H.; Davies, S.; Alexander, G.J.; Lomas, D.J.

2011-01-01

Aim: To evaluate the diagnostic accuracy of multidetector computed tomography (MDCT) for hepatocellular carcinoma (HCC) in cirrhotic patients undergoing liver transplantation. Secondary aims were to examine the effect of radiologist experience and lesion size on diagnostic accuracy. Materials and methods: Thirty-nine patients (72% male with a mean age of 56.5 years) underwent liver transplantation following preoperative triple-phase MDCT examination of the liver. MDCT examinations were retrospectively independently reviewed by three radiologists for the presence and location of suspected HCCs, with the diagnostic confidence recorded using a five-point confidence scale. MDCT examinations were compared with explant specimens for histopathological correlation. Results: Histopathological results demonstrated 46 HCCs in 29 of the 39 patients. Analysis demonstrated a sensitivity of 65-75% and specificity of 47-88% for detection of HCC lesions. The sensitivity dropped to 48-57% for lesions of size ≤20 mm. As the diagnostic confidence increased, there was a further decrease in the sensitivity (4-26%). The radiologist with the greatest number of years experience was found to have a significantly higher accuracy of detection of HCC lesions compared with the least experienced radiologist. Conclusion: Larger lesion size of HCC and greater number of years experience of the radiologist resulted in significantly higher accuracy of HCC lesion detection. The overall sensitivity and specificity results for MDCT detection of HCC are comparable to previous helical CT imaging.

Work stress in radiologists. A pilot study.

Science.gov (United States)

Magnavita, N; Fileni, A; Magnavita, G; Mammi, F; Mirk, P; Roccia, K; Bergamaschi, A

2008-04-01

We studied occupational stress and its psychosocial effects in a sample of Italian radiologists and radiotherapists: Radiologists and radiotherapists attending two medical conferences were invited to complete a questionnaire comprising four sections investigating the risk of occupational stress (organisational discomfort, Karasek's Job Content Questionnaire, Siegrist's Effort-Reward Imbalance, Warr's Job Satisfaction) and four sections investigating the health effects of such stress (Goldberg's Anxiety and Depression Scales, General Health Questionnaire, Lifestyles Questionnaire). Radiologists and radiotherapists generally expressed high levels of control, reward and satisfaction. However, 38.5% complained of severe organisational discomfort, 24% reported job strain, 28% reported effort/reward imbalance and 25% were dissatisfied. Female radiologists and radiotherapists showed higher levels of organisational discomfort than their male colleagues. Younger and less experienced radiologists and radiotherapists had higher strain scores than their older and more experienced colleagues. A significant correlation was observed between stress predictors and the effects of stress on health, including depression and anxiety, psychological distress and unhealthy lifestyles. Radiologists and radiotherapists are exposed to major occupational stress factors, and a significant percentage of them suffer from workplace stress. A special effort is required to prevent this condition.

Evaluation of solitary pulmonary nodules by integrated PET/CT: improved accuracy by FDG uptake pattern and CT findings

International Nuclear Information System (INIS)

Joon Young Choi; Kyung Soo Lee; O Jung Kwon; Young Mog Shim; Kyung-Han Lee; Yong Choi; Yearn Seong Choe; Byung-Tae Kim

2004-01-01

Objective: FDG PET is useful to differentiate malignancy from benign lesions in the evaluation of solitary pulmonary nodules (SPNs). However, FDG PET showed false positive results in benign inflammatory lesions such as tuberculosis and organizing pneumonia. Furthermore, malignant tumors such as adenocarcinoma (AC) with bronchioloalveolar carcinoma (BAC) type had lower FDG uptake than other cell types of non-small cell lung cancer. We investigated whether FDG uptake pattern and image findings of CT for attenuation correction could improve accuracy for evaluating SPNs over SUV in integrated PET/CT imaging using FDG. Methods: Forty patients (M:F = 23:17, mean age 58.2±9.4 yrs) with non-calcified SPNs (diameter on CT 30 mm, no significant mediastinal node enlargement, no atelectasis) were included. All subjects underwent integrated PET/CT imaging using FDG. One nuclear medicine physician and 1 chest radiologist interpreted the PET and non-contrast CT images for attenuation correction, respectively. On PET images, maximum SUV of SPN was acquired, and FDG uptake pattern was categorized as diffusely increased or heterogeneously increased with upper threshold of window setting adjusted to maximum SUV of each nodule. A radiologist interpreted SPNs as benign or malignant based on CT images with lung and mediastinai window settings blinded to PET findings. Results: On pathological exam, 30 SPNs were confirmed to be malignant (11 AC with non-BAC type, 8 AC with BAC type, 8 squamous cell carcinoma, 1 adenosquamous cell carcinoma, 1 neuroendocrine carcinoma, 1 large cell carcinoma), and 10 were benign (4 tuberculosis, 3 organizing pneumonia, 2 sclerosing pneumocytoma, 1 non-specific inflammation). All 5 nodules with max SUV 7.0 except one with tuberculoma had malignancy. When only nodules with diffusely increased uptake were considered malignant in indeterminate group with max SUV of 4.0 to 7.0, PET could diagnose 5 of 9 malignant nodules with one false positive nodule. In 6 of

Improving Accuracy of Processing by Adaptive Control Techniques

Directory of Open Access Journals (Sweden)

N. N. Barbashov

2016-01-01

Full Text Available When machining the work-pieces a range of scatter of the work-piece dimensions to the tolerance limit is displaced in response to the errors. To improve an accuracy of machining and prevent products from defects it is necessary to diminish the machining error components, i.e. to improve the accuracy of machine tool, tool life, rigidity of the system, accuracy of adjustment. It is also necessary to provide on-machine adjustment after a certain time. However, increasing number of readjustments reduces the performance and high machine and tool requirements lead to a significant increase in the machining cost.To improve the accuracy and machining rate, various devices of active control (in-process gaging devices, as well as controlled machining through adaptive systems for a technological process control now become widely used. Thus, the accuracy improvement in this case is reached by compensation of a majority of technological errors. The sensors of active control can provide improving the accuracy of processing by one or two quality classes, and simultaneous operation of several machines.For efficient use of sensors of active control it is necessary to develop the accuracy control methods by means of introducing the appropriate adjustments to solve this problem. Methods based on the moving average, appear to be the most promising for accuracy control, since they contain information on the change in the last several measured values of the parameter under control.When using the proposed method in calculation, the first three members of the sequence of deviations remain unchanged, therefore 1 1 x  x , 2 2 x  x , 3 3 x  x Then, for each i-th member of the sequence we calculate that way: , ' i i i x  x  k x , where instead of the i x values will be populated with the corresponding values ' i x calculated as an average of three previous members:3 ' 1  2  3  i i i i x x x x .As a criterion for the estimate of the control

A dedicated BI-RADS training programme: Effect on the inter-observer variation among screening radiologists

International Nuclear Information System (INIS)

Timmers, J.M.H.; Doorne-Nagtegaal, H.J. van; Verbeek, A.L.M.; Heeten, G.J. den; Broeders, M.J.M.

2012-01-01

Introduction: The Breast Imaging Reporting and Data System (BI-RADS) was introduced in the Dutch breast cancer screening programme to improve communication between medical specialists. Following introduction, a substantial variation in the use of the BI-RADS lexicon for final assessment categories was noted among screening radiologists. We set up a dedicated training programme to reduce this variation. This study evaluates whether this programme was effective. Materials and methods: Two comparable test sets were read before and after completion of the training programme. Each set contained 30 screening mammograms of referred women selected from screening practice. The sets were read by 25 experienced and 30 new screening radiologists. Cohen's kappa (κ) was used to calculate the inter-observer agreement. The BI-RADS 2003 version was implemented in the screening programme as the BI-RADS 2008 version requires the availability of diagnostic work-up, and this is unavailable. Results: The inter-observer agreement of all participating radiologists (n = 55) with the expert panel increased from a pre-training κ-value of 0.44 to a post-training κ-value of 0.48 (p = 0.14). The inter-observer agreement of the new screening radiologists (n = 30) with the expert panel increased from κ = 0.41 to κ = 0.50 (p = 0.01), whereas there was no difference in agreement among the 25 experienced radiologists (from κ = 0.48 to κ = 0.46, p = 0.60). Conclusion: Our training programme in the BI-RADS lexicon resulted in a significant improvement of agreement among new screening radiologists. Overall, the agreement among radiologists was moderate (guidelines Landis and Koch). This is in line with results found in the literature

Physician rating websites: do radiologists have an online presence?

Science.gov (United States)

Gilbert, Kirven; Hawkins, C Matthew; Hughes, Danny R; Patel, Kishen; Gogia, Navdeep; Sekhar, Aarti; Duszak, Richard

2015-08-01

Given that patient satisfaction and provider transparency intersect on online physician-rating websites, we aimed to assess radiologist representation on these increasingly popular sites. From a directory of all Medicare participating physicians, we randomly selected 1,000 self-designated diagnostic radiologists and manually extracted their rating information from five popular online physician-review websites (HealthGrades, Healthcare Reviews, RateMDs, Kudzu, and Yelp). Using automated web "data-scraping" techniques, we separately extracted all radiologist and nonradiologist rating information from a single amenable site (Healthcare Reviews). Rating characteristics were analyzed. Of 1,000 sampled self-designated diagnostic radiologists representing all 50 states, only 197 (19.7%) were profiled on any of the five online physician-review websites. Only 24 (2.4%) were rated on two of the sites, and none was profiled on ≥3 sites. Of all 6,775 physicians listed on a single electronically interrogated site, only 30 (0.4%) were radiologists. With 28,555 (5.2%) of all 547,849 Medicare-participating physicians identified as diagnostic radiologists, radiologists were thus significantly underrepresented online (P < .0001). Although reviewed radiologists and nonradiologists were rated online by similar numbers of patients (1.13 ± 0.43 versus 1.03 ± 0.22, P = .22), radiologists were rated (on a low to high score of 1 to 10) significantly higher than nonradiologists (median 8.5 versus 5, P = .04). Most diagnostic radiologists are not profiled on common online physician-rating websites, and they are significantly underrepresented compared with nonradiologists. Reviewed radiologists, however, scored favorably. Given the potential for patient satisfaction scores and public domain information to affect referrals and future value-based payments, initiatives to enhance radiologists' online presence are advised. Copyright © 2015 American College of Radiology. Published by

Cochlear implant: what the radiologist should know

Directory of Open Access Journals (Sweden)

Natalia Delage Gomes

2013-06-01

Full Text Available Cochlear implant is the method of choice in the treatment of deep sensorineural hypoacusis, particularly in patients where conventional amplification devices do not imply noticeable clinical improvement. Imaging findings are crucial in the indication or contraindication for such surgical procedure. In the assessment of the temporal bone, radiologists should be familiar with relative or absolute contraindication factors, as well as with factors that might significantly complicate the implantation. Some criteria such as cochlear nerve aplasia, labyrinthine and/or cochlear aplasia are still considered as absolute contraindications, in spite of studies bringing such criteria into question. Cochlear dysplasias constitute relative contraindications, among them labyrinthitis ossificans is highlighted. Other alterations may be mentioned as complicating agents in the temporal bone assessment, namely, hypoplasia of the mastoid process, aberrant facial nerve, otomastoiditis, otosclerosis, dehiscent jugular bulb, enlarged endolymphatic duct and sac. The experienced radiologist assumes an important role in the evaluation of this condition.

Cochlear implant: what the radiologist should know

International Nuclear Information System (INIS)

Gomes, Natalia Delage; Couto, Caroline Laurita Batista; Gaiotti, Juliana Oggioni; Costa, Ana Maria Doffemond; Ribeiro, Marcelo Almeida; Diniz, Renata Lopes Furletti Caldeira

2013-01-01

Cochlear implant is the method of choice in the treatment of deep sensorineural hypoacusis, particularly in patients where conventional amplification devices do not imply noticeable clinical improvement. Imaging findings are crucial in the indication or contraindication for such surgical procedure. In the assessment of the temporal bone, radiologists should be familiar with relative or absolute contraindication factors, as well as with factors that might significantly complicate the implantation. Some criteria such as cochlear nerve aplasia, labyrinthine and/or cochlear aplasia are still considered as absolute contraindications, in spite of studies bringing such criteria into question. Cochlear dysplasias constitute relative contraindications, among them labyrinthitis ossificans is highlighted. Other alterations may be mentioned as complicating agents in the temporal bone assessment, namely, hypoplasia of the mastoid process, aberrant facial nerve, otomastoiditis, otosclerosis, dehiscent jugular bulb, enlarged endolymphatic duct and sac. The experienced radiologist assumes an important role in the evaluation of this condition. (author)

Recent advances in neonatology - new tasks for the radiologist

International Nuclear Information System (INIS)

Klebermass, K.; Birnbacher, R.; Weninger, M.; Pollak, A.

2000-01-01

Modern neonatology comprises care for a growing number of infants with congenital abnormalities and an increasing number of premature born infants. The survival rates of premature infants have increased dramatically during the past decade. This increase in survival rates can be attributed to improved prenatal and obstetric management and to advances in neonatal intensive care medicine. Radiological support: Neonatology has become a pediatric subspeciality of its own resulting in the demand for an equally specialised radiological support. Therefore, the availability of a children's radiologist for radiological and sonographic examinations is mandatory (24 hours a day) for optimal patient care on a neonatal intensive care unit. A good cooperation between radiologist and neonatologist in neonatal intensive care medicine is therefore warranted. (orig.) [de

Is Value-Driven Health Care an Unfunded Mandate for Radiologists?

Science.gov (United States)

McGinty, Geraldine

2016-02-01

The goals of the 2010 Patient Protection and Affordable Care Act (ACA) can be summed up by the Triple Aim, as defined by the Institute for Healthcare Improvement: Improve population health, optimize the patient experience, and reduce the costs of care. Despite recent reimbursement reductions, radiologists have increasing opportunities to participate in value-based payment programs and should leverage those opportunities.

Nuisance levels of noise effects radiologists' performance

Science.gov (United States)

McEntee, Mark F.; Coffey, Amina; Ryan, John; O'Beirne, Aaron; Toomey, Rachel; Evanoff, Micheal; Manning, David; Brennan, Patrick C.

2010-02-01

This study aimed to measure the sound levels in Irish x-ray departments. The study then established whether these levels of noise have an impact on radiologists performance Noise levels were recorded 10 times within each of 14 environments in 4 hospitals, 11 of which were locations where radiologic images are judged. Thirty chest images were then presented to 26 senior radiologists, who were asked to detect up to three nodular lesions within 30 posteroanterior chest x-ray images in the absence and presence of noise at amplitude demonstrated in the clinical environment. The results demonstrated that noise amplitudes rarely exceeded that encountered with normal conversation with the maximum mean value for an image-viewing environment being 56.1 dB. This level of noise had no impact on the ability of radiologists to identify chest lesions with figure of merits of 0.68, 0.69, and 0.68 with noise and 0.65, 0.68, and 0.67 without noise for chest radiologists, non-chest radiologists, and all radiologists, respectively. the difference in their performance using the DBM MRMC method was significantly better with noise than in the absence of noise at the 90% confidence interval (p=0.077). Further studies are required to establish whether other aspects of diagnosis are impaired such as recall and attention and the effects of more unexpected noise on performance.

A survey on visual information search behavior and requirements of radiologists.

Science.gov (United States)

Markonis, D; Holzer, M; Dungs, S; Vargas, A; Langs, G; Kriewel, S; Müller, H

2012-01-01

The main objective of this study is to learn more on the image use and search requirements of radiologists. These requirements will then be taken into account to develop a new search system for images and associated meta data search in the Khresmoi project. Observations of the radiology workflow, case discussions and a literature review were performed to construct a survey form that was given online and in paper form to radiologists. Eye tracking was performed on a radiology viewing station to analyze typical tasks and to complement the survey. In total 34 radiologists answered the survey online or on paper. Image search was mentioned as a frequent and common task, particularly for finding cases of interest for differential diagnosis. Sources of information besides the Internet are books and discussions with colleagues. Search for images is unsuccessful in around 25% of the cases, stopping the search after around 10 minutes. The most common reason for failure is that target images are considered rare. Important additions for search requested in the survey are filtering by pathology and modality, as well as search for visually similar images and cases. Few radiologists are familiar with visual retrieval but they desire the option to upload images for searching similar ones. Image search is common in radiology but few radiologists are fully aware of visual information retrieval. Taking into account the many unsuccessful searches and time spent for this, a good image search could improve the situation and help in clinical practice.

Reading screening mammograms - Attitudes among radiologists and radiographers about skill mix

DEFF Research Database (Denmark)

Johansen, Lena Westphal; Brodersen, John

2011-01-01

INTRODUCTION: Because of shortage of personnel for the Danish mammography screening programme, the aim of this study was to investigate the attitudes of radiologists and radiographers towards a future implementation of radiographers reading screening mammograms. MATERIALS AND METHODS: Seven...... of managers, and improved working relations. Organization related obstacles: shortage of radiographers and negative attitudes of managers. Professional related possibilities: positive experience with skill mix. Professional related obstacles: worries about negative consequences for the training...... and financial consequences of skill mix. Despite of this all radiologists and radiographers experienced with skill mix were strong advocates for reading radiographers....

Potential clinical impact of advanced imaging and computer-aided diagnosis in chest radiology: importance of radiologist's role and successful observer study.

Science.gov (United States)

Li, Feng

2015-07-01

This review paper is based on our research experience in the past 30 years. The importance of radiologists' role is discussed in the development or evaluation of new medical images and of computer-aided detection (CAD) schemes in chest radiology. The four main topics include (1) introducing what diseases can be included in a research database for different imaging techniques or CAD systems and what imaging database can be built by radiologists, (2) understanding how radiologists' subjective judgment can be combined with technical objective features to improve CAD performance, (3) sharing our experience in the design of successful observer performance studies, and (4) finally, discussing whether the new images and CAD systems can improve radiologists' diagnostic ability in chest radiology. In conclusion, advanced imaging techniques and detection/classification of CAD systems have a potential clinical impact on improvement of radiologists' diagnostic ability, for both the detection and the differential diagnosis of various lung diseases, in chest radiology.

MRI screening for silicone breast implant rupture: accuracy, inter- and intraobserver variability using explantation results as reference standard

Energy Technology Data Exchange (ETDEWEB)

Maijers, M.C.; Ritt, M.J.P.F. [VU University Medical Centre, Department of Plastic, Reconstructive and Hand Surgery, De Boelelaan 1117, PO Box 7057, Amsterdam (Netherlands); Niessen, F.B. [VU University Medical Centre, Department of Plastic, Reconstructive and Hand Surgery, De Boelelaan 1117, PO Box 7057, Amsterdam (Netherlands); Jan van Goyen Clinic, Department of Plastic Surgery, Amsterdam (Netherlands); Veldhuizen, J.F.H. [MRI Centre, Amsterdam (Netherlands); Manoliu, R.A. [MRI Centre, Amsterdam (Netherlands); VU University Medical Centre, Department of Radiology, Amsterdam (Netherlands)

2014-06-15

The recall of Poly Implant Prothese (PIP) silicone breast implants in 2010 resulted in large numbers of asymptomatic women with implants who underwent magnetic resonance imaging (MRI) screening. This study's aim was to assess the accuracy and interobserver variability of MRI screening in the detection of rupture and extracapsular silicone leakage. A prospective study included 107 women with 214 PIP implants who underwent explantation preceded by MRI. In 2013, two radiologists blinded for previous MRI findings or outcome at surgery, independently re-evaluated all MRI examinations. A structured protocol described the MRI findings. The ex vivo findings served as reference standard. In 208 of the 214 explanted prostheses, radiologists agreed independently about the condition of the implants. In five of the six cases they disagreed (2.6 %), but subsequently reached consensus. A sensitivity of 93 %, specificity of 93 %, positive predictive value of 77 % and negative predictive value of 98 % was found. The interobserver agreement was excellent (kappa value of 0.92). MRI has a high accuracy in diagnosing rupture in silicone breast implants. Considering the high kappa value of interobserver agreement, MRI appears to be a consistent diagnostic test. A simple, uniform classification, may improve communication between radiologist and plastic surgeon. (orig.)

MRI screening for silicone breast implant rupture: accuracy, inter- and intraobserver variability using explantation results as reference standard

International Nuclear Information System (INIS)

Maijers, M.C.; Ritt, M.J.P.F.; Niessen, F.B.; Veldhuizen, J.F.H.; Manoliu, R.A.

2014-01-01

The recall of Poly Implant Prothese (PIP) silicone breast implants in 2010 resulted in large numbers of asymptomatic women with implants who underwent magnetic resonance imaging (MRI) screening. This study's aim was to assess the accuracy and interobserver variability of MRI screening in the detection of rupture and extracapsular silicone leakage. A prospective study included 107 women with 214 PIP implants who underwent explantation preceded by MRI. In 2013, two radiologists blinded for previous MRI findings or outcome at surgery, independently re-evaluated all MRI examinations. A structured protocol described the MRI findings. The ex vivo findings served as reference standard. In 208 of the 214 explanted prostheses, radiologists agreed independently about the condition of the implants. In five of the six cases they disagreed (2.6 %), but subsequently reached consensus. A sensitivity of 93 %, specificity of 93 %, positive predictive value of 77 % and negative predictive value of 98 % was found. The interobserver agreement was excellent (kappa value of 0.92). MRI has a high accuracy in diagnosing rupture in silicone breast implants. Considering the high kappa value of interobserver agreement, MRI appears to be a consistent diagnostic test. A simple, uniform classification, may improve communication between radiologist and plastic surgeon. (orig.)

Implementing an ultrasound-based protocol for diagnosingappendicitis while maintaining diagnostic accuracy

International Nuclear Information System (INIS)

Van Atta, Angela J.; Baskin, Henry J.; Maves, Connie K.; Dansie, David M.; Rollins, Michael D.; Bolte, Robert G.; Mundorff, Michael B.; Andrews, Seth P.

2015-01-01

The use of ultrasound to diagnose appendicitis in children is well-documented but not universally employed outside of pediatric academic centers, especially in the United States. Various obstacles make it difficult for institutions and radiologists to abandon a successful and accurate CT-based imaging protocol in favor of a US-based protocol. To describe how we overcame barriers to implementing a US-based appendicitis protocol among a large group of nonacademic private-practice pediatric radiologists while maintaining diagnostic accuracy and decreasing medical costs. A multidisciplinary team of physicians (pediatric surgery, pediatric emergency medicine and pediatric radiology) approved an imaging protocol using US as the primary modality to evaluate suspected appendicitis with CT for equivocal cases. The protocol addressed potential bias against US and accommodated for institutional limitations of radiologist and sonographer experience and availability. Radiologists coded US reports according to the probability of appendicitis. Radiology reports were compared with clinical outcomes to assess diagnostic accuracy. During the study period, physicians from each group were apprised of the interim US protocol accuracy results. Problematic cases were discussed openly. A total of 512 children were enrolled and underwent US for evaluation of appendicitis over a 30-month period. Diagnostic accuracy was comparable to published results for combined US/CT protocols. Comparing the first 12 months to the last 12 months of the study period, the proportion of children achieving an unequivocal US result increased from 30% (51/169) to 53% (149/282) and the proportion of children undergoing surgery based solely on US findings increased from 55% (23/42) to 84% (92/109). Overall, 63% (325/512) of patients in the protocol did not require a CT. Total patient costs were reduced by $30,182 annually. We overcame several barriers to implementing a US protocol. During the study period our

Implementing an ultrasound-based protocol for diagnosingappendicitis while maintaining diagnostic accuracy

Energy Technology Data Exchange (ETDEWEB)

Van Atta, Angela J. [University of Utah School of Medicine, Salt Lake City, UT (United States); Baskin, Henry J.; Maves, Connie K.; Dansie, David M. [Primary Children' s Hospital, Department of Radiology, Salt Lake City, UT (United States); Rollins, Michael D. [University of Utah School of Medicine, Department of Surgery, Division of Pediatric Surgery, Salt Lake City, UT (United States); Bolte, Robert G. [University of Utah School of Medicine, Department of Pediatrics, Division of Pediatric Emergency Medicine, Salt Lake City, UT (United States); Mundorff, Michael B.; Andrews, Seth P. [Primary Children' s Hospital, Systems Improvement, Salt Lake City, UT (United States)

2015-05-01

The use of ultrasound to diagnose appendicitis in children is well-documented but not universally employed outside of pediatric academic centers, especially in the United States. Various obstacles make it difficult for institutions and radiologists to abandon a successful and accurate CT-based imaging protocol in favor of a US-based protocol. To describe how we overcame barriers to implementing a US-based appendicitis protocol among a large group of nonacademic private-practice pediatric radiologists while maintaining diagnostic accuracy and decreasing medical costs. A multidisciplinary team of physicians (pediatric surgery, pediatric emergency medicine and pediatric radiology) approved an imaging protocol using US as the primary modality to evaluate suspected appendicitis with CT for equivocal cases. The protocol addressed potential bias against US and accommodated for institutional limitations of radiologist and sonographer experience and availability. Radiologists coded US reports according to the probability of appendicitis. Radiology reports were compared with clinical outcomes to assess diagnostic accuracy. During the study period, physicians from each group were apprised of the interim US protocol accuracy results. Problematic cases were discussed openly. A total of 512 children were enrolled and underwent US for evaluation of appendicitis over a 30-month period. Diagnostic accuracy was comparable to published results for combined US/CT protocols. Comparing the first 12 months to the last 12 months of the study period, the proportion of children achieving an unequivocal US result increased from 30% (51/169) to 53% (149/282) and the proportion of children undergoing surgery based solely on US findings increased from 55% (23/42) to 84% (92/109). Overall, 63% (325/512) of patients in the protocol did not require a CT. Total patient costs were reduced by $30,182 annually. We overcame several barriers to implementing a US protocol. During the study period our

The Royal College of Radiologists Breast Group breast imaging classification

International Nuclear Information System (INIS)

Maxwell, A.J.; Ridley, N.T.; Rubin, G.; Wallis, M.G.; Gilbert, F.J.; Michell, M.J.

2009-01-01

Standardisation of the classification of breast imaging reports will improve communication between the referrer and the radiologist and avoid ambiguity, which may otherwise lead to mismanagement of patients. Following wide consultation, Royal College of Radiologists Breast Group has produced a scoring system for the classification of breast imaging. This will facilitate audit and the development of nationally agreed standards for the investigation of women with breast disease. This five-point system is as follows: 1, normal; 2, benign findings; 3, indeterminate/probably benign findings; 4, findings suspicious of malignancy; 5, findings highly suspicious of malignancy. It is recommended that this be used in the reporting of all breast imaging examinations in the UK.

Single reading with computer-aided detection performed by selected radiologists in a breast cancer screening program

Energy Technology Data Exchange (ETDEWEB)

Bargalló, Xavier, E-mail: xbarga@clinic.cat [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Santamaría, Gorane; Amo, Montse del; Arguis, Pedro [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Ríos, José [Biostatistics and Data Management Core Facility, IDIBAPS, (Hospital Clinic) C/ Mallorca, 183. Floor -1. Office #60. 08036 Barcelona (Spain); Grau, Jaume [Preventive Medicine and Epidemiology Unit, Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain); Burrel, Marta; Cores, Enrique; Velasco, Martín [Department of Radiology (CDIC), Hospital Clínic de Barcelona, C/ Villarroel, 170, 08036 Barcelona (Spain)

2014-11-15

Highlights: • 1-The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD. • 2-The cancer detection rate improved at the cost of increasing recall rate. • 3-CAD, used by breast radiologists, did not help to detect more cancers. - Abstract: Objectives: To assess the impact of shifting from a standard double reading plus arbitration protocol to a single reading by experienced radiologists assisted by computer-aided detection (CAD) in a breast cancer screening program. Methods: This was a prospective study approved by the ethics committee. Data from 21,321 consecutive screening mammograms in incident rounds (2010–2012) were read following a single reading plus CAD protocol and compared with data from 47,462 consecutive screening mammograms in incident rounds (2004–2010) that were interpreted following a double reading plus arbitration protocol. For the single reading, radiologists were selected on the basis of the appraisement of their previous performance. Results: Period 2010–2012 vs. period 2004–2010: Cancer detection rate (CDR): 6.1‰ (95% confidence interval: 5.1–7.2) vs. 5.25‰; Recall rate (RR): 7.02% (95% confidence interval: 6.7–7.4) vs. 7.24% (selected readers before arbitration) and vs. 3.94 (all readers after arbitration); Predictive positive value of recall: 8.69% vs. 13.32%. Average size of invasive cancers: 14.6 ± 9.5 mm vs. 14.3 ± 9.5 mm. Stage: 0 (22.3/26.1%); I (59.2/50.8%); II (19.2/17.1%); III (3.1/3.3%); IV (0/1.9%). Specialized breast radiologists performed better than general radiologists. Conclusions: The cancer detection rate of the screening program improved using a single reading protocol by experienced radiologists assisted by CAD, at the cost of a moderate increase of the recall rate mainly related to the lack of arbitration.

Prevalence of burnout among musculoskeletal radiologists

Energy Technology Data Exchange (ETDEWEB)

Chew, Felix S.; Porrino, Jack A.; Mulcahy, Hyojeong; Relyea-Chew, Annemarie [University of Washington, Department of Radiology, Seattle, WA (United States); Mulcahy, Michael J. [Central Washington University, Department of Sociology, Ellensburg, WA (United States)

2017-04-15

Burnout is a job-related psychological syndrome with three aspects: emotional exhaustion, depersonalization, and perceived lack of personal accomplishment. Burnout is associated with deleterious effects on both workers and their work. When burnout affects physicians, their well-being, longevity, and care of patients are at risk. Recent studies concerning physician burnout treat specialists such as radiologists as one group. We studied burnout in musculoskeletal (MSK) subspecialist radiologists. An institutional review board exemption was obtained. Society of Skeletal Radiology members received invitations to an anonymous survey that included questions from the Maslach Burnout Inventory trademark (MBI) measuring all three aspects of burnout. The response rate was 36.4% (433/1190). The prevalence of emotional exhaustion was 61.7% (255/413), of depersonalization 53.3% (219/411), and of perceived lack of personal accomplishment 39.6% (161/407). Only 19.5% (79/405) of MSK radiologists reported no burnout, while 80.5% (326/405) reported burnout along one or more dimensions. For all three dimensions, the prevalence was higher and the mean severity was worse for private practice compared with academic practice. The prevalence of burnout was affected more by practice setting than by gender. Burnout prevalence and severity also varied systematically with years since completion of training. Among MSK radiologists, we found a much higher prevalence and greater severity of burnout than has been previously reported for radiologists and other physicians. There were differences in prevalence and severity of burnout among practice settings, genders, and longevity cohorts. (orig.)

Prevalence of burnout among musculoskeletal radiologists

International Nuclear Information System (INIS)

Chew, Felix S.; Porrino, Jack A.; Mulcahy, Hyojeong; Relyea-Chew, Annemarie; Mulcahy, Michael J.

2017-01-01

Burnout is a job-related psychological syndrome with three aspects: emotional exhaustion, depersonalization, and perceived lack of personal accomplishment. Burnout is associated with deleterious effects on both workers and their work. When burnout affects physicians, their well-being, longevity, and care of patients are at risk. Recent studies concerning physician burnout treat specialists such as radiologists as one group. We studied burnout in musculoskeletal (MSK) subspecialist radiologists. An institutional review board exemption was obtained. Society of Skeletal Radiology members received invitations to an anonymous survey that included questions from the Maslach Burnout Inventory trademark (MBI) measuring all three aspects of burnout. The response rate was 36.4% (433/1190). The prevalence of emotional exhaustion was 61.7% (255/413), of depersonalization 53.3% (219/411), and of perceived lack of personal accomplishment 39.6% (161/407). Only 19.5% (79/405) of MSK radiologists reported no burnout, while 80.5% (326/405) reported burnout along one or more dimensions. For all three dimensions, the prevalence was higher and the mean severity was worse for private practice compared with academic practice. The prevalence of burnout was affected more by practice setting than by gender. Burnout prevalence and severity also varied systematically with years since completion of training. Among MSK radiologists, we found a much higher prevalence and greater severity of burnout than has been previously reported for radiologists and other physicians. There were differences in prevalence and severity of burnout among practice settings, genders, and longevity cohorts. (orig.)

Accuracy Improvement of Neutron Nuclear Data on Minor Actinides

Science.gov (United States)

Harada, Hideo; Iwamoto, Osamu; Iwamoto, Nobuyuki; Kimura, Atsushi; Terada, Kazushi; Nakao, Taro; Nakamura, Shoji; Mizuyama, Kazuhito; Igashira, Masayuki; Katabuchi, Tatsuya; Sano, Tadafumi; Takahashi, Yoshiyuki; Takamiya, Koichi; Pyeon, Cheol Ho; Fukutani, Satoshi; Fujii, Toshiyuki; Hori, Jun-ichi; Yagi, Takahiro; Yashima, Hiroshi

2015-05-01

Improvement of accuracy of neutron nuclear data for minor actinides (MAs) and long-lived fission products (LLFPs) is required for developing innovative nuclear system transmuting these nuclei. In order to meet the requirement, the project entitled as "Research and development for Accuracy Improvement of neutron nuclear data on Minor ACtinides (AIMAC)" has been started as one of the "Innovative Nuclear Research and Development Program" in Japan at October 2013. The AIMAC project team is composed of researchers in four different fields: differential nuclear data measurement, integral nuclear data measurement, nuclear chemistry, and nuclear data evaluation. By integrating all of the forefront knowledge and techniques in these fields, the team aims at improving the accuracy of the data. The background and research plan of the AIMAC project are presented.

Toward Augmented Radiologists: Changes in Radiology Education in the Era of Machine Learning and Artificial Intelligence.

Science.gov (United States)

Tajmir, Shahein H; Alkasab, Tarik K

2018-06-01

Radiology practice will be altered by the coming of artificial intelligence, and the process of learning in radiology will be similarly affected. In the short term, radiologists will need to understand the first wave of artificially intelligent tools, how they can help them improve their practice, and be able to effectively supervise their use. Radiology training programs will need to develop curricula to help trainees acquire the knowledge to carry out this new supervisory duty of radiologists. In the longer term, artificially intelligent software assistants could have a transformative effect on the training of residents and fellows, and offer new opportunities to bring learning into the ongoing practice of attending radiologists. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Radiologists' Training, Experience, and Attitudes About Elder Abuse Detection.

Science.gov (United States)

Rosen, Tony; Bloemen, Elizabeth M; Harpe, Jasmin; Sanchez, Allen M; Mennitt, Kevin W; McCarthy, Thomas J; Nicola, Refky; Murphy, Kieran; LoFaso, Veronica M; Flomenbaum, Neal; Lachs, Mark S

2016-12-01

Elder abuse is underrecognized, and identification of subtle cases requires a high index of suspicion among all health care providers. Because many geriatric injury victims undergo radiographic imaging, diagnostic radiologists may be well positioned to identify injury patterns suggestive of abuse. Little is known about radiologists' experience with elder abuse. Our goal was to describe knowledge, attitudes, training, and practice experience in elder abuse detection among diagnostic radiologists. We conducted 19 interviews with diagnostic radiologists at a large urban academic medical center using a semistructured format. Data from these sessions were coded and analyzed to identify themes. Only two radiologists reported any formal or informal training in elder abuse detection. All subjects believed they had missed cases of elder abuse. Even experienced radiologists reported never having received a request from a referring physician to assess images for evidence suggestive of elder abuse. All subjects reported a desire for additional elder abuse training. Also, subjects identified radiographic findings or patterns potentially suggestive of elder abuse, including high-energy injuries such as upper rib fractures, injuries in multiple stages of healing, and injuries inconsistent with reported mechanism. Radiologists are uniquely positioned to identify elder abuse. Though training in detection is currently lacking, providers expressed a desire for increased knowledge. In addition, radiologists were able to identify radiographic findings suggestive of elder abuse. On the basis of these findings, we plan to conduct additional studies to define pathognomonic injury patterns and to explore how to empower radiologists to incorporate detection into their practice.

THE ACCURACY AND BIAS EVALUATION OF THE USA UNEMPLOYMENT RATE FORECASTS. METHODS TO IMPROVE THE FORECASTS ACCURACY

Directory of Open Access Journals (Sweden)

MIHAELA BRATU (SIMIONESCU

2012-12-01

Full Text Available In this study some alternative forecasts for the unemployment rate of USA made by four institutions (International Monetary Fund (IMF, Organization for Economic Co-operation and Development (OECD, Congressional Budget Office (CBO and Blue Chips (BC are evaluated regarding the accuracy and the biasness. The most accurate predictions on the forecasting horizon 201-2011 were provided by IMF, followed by OECD, CBO and BC.. These results were gotten using U1 Theil’s statistic and a new method that has not been used before in literature in this context. The multi-criteria ranking was applied to make a hierarchy of the institutions regarding the accuracy and five important accuracy measures were taken into account at the same time: mean errors, mean squared error, root mean squared error, U1 and U2 statistics of Theil. The IMF, OECD and CBO predictions are unbiased. The combined forecasts of institutions’ predictions are a suitable strategy to improve the forecasts accuracy of IMF and OECD forecasts when all combination schemes are used, but INV one is the best. The filtered and smoothed original predictions based on Hodrick-Prescott filter, respectively Holt-Winters technique are a good strategy of improving only the BC expectations. The proposed strategies to improve the accuracy do not solve the problem of biasness. The assessment and improvement of forecasts accuracy have an important contribution in growing the quality of decisional process.

The relationship between oncologists and peripheral hospital radiologists in the north-west of England

International Nuclear Information System (INIS)

Bungay, Peter M.; Carrington, Bernadette M.; Corgie, Delphine; Eardley, Anne

2002-01-01

AIM: To audit the relationship between Cancer Centre oncologists visiting peripheral hospitals and peripheral hospital radiologists by assessing (i) oncologists' knowledge of local radiological services; (ii) oncologists' perceptions of peripheral radiological services; (iii) peripheral radiologist's perceptions of oncologists; (iv) barriers to communication. MATERIALS AND METHODS: A postal questionnaire was sent to all radiology departments visited by an oncologist, and to all medical and clinical oncologists from two regional oncology centres. RESULTS: The response rate was 100% (21 peripheral hospital radiology departments and all 35 oncologists). (i) Oncologists' knowledge of peripheral hospital imaging modalities was limited (especially MRI and intervention). (ii) 72% of oncologists rated the peripheral hospital radiology service as excellent or good, 46% rated the radiology report quality excellent to good. Deficiencies in oncological reports were identified. (iii) 44% of radiologists thought the oncologist did not relate well with the local radiology department. 50% of radiologists did not know the visiting oncologist's specialist interest. (iv) 69% of oncologists did not regularly attend peripheral hospital clinico-radiological meetings. Lack of written and oral information was hampering both specialities. CONCLUSION: Communication between oncologists and the local radiology department should include: (1) information about local radiology services for visiting oncologists (including trainees) and on the oncology team for radiologists; (2) standardized report content; (3) improved clinical information for radiologists; (4) regular clinico-radiological meetings. Bungay, P.M. et al. (2002)

Extremity doses to interventional radiologists

International Nuclear Information System (INIS)

Wihtby, M.; Martin, C. J.

2002-01-01

Radiologists performing interventional procedures are often required to stand close to the patient's side when carrying out manipulations under fluoroscopic control. This can result in their extremities receiving a high radiation dose, due to scattered radiation. These doses are sometimes high enough to warrant that the radiologist in question be designated a classified radiation worker. Classification in the UK is a result of any worker receiving or likely to receive in the course of their duties in excess of 3/10ths of any annual dose limit (500mSv to extremities, skin). The doses to the legs of radiologists have received less attention than those to the hands, however the doses may be high, due to the proximity of the legs and feet to scattered radiation. The legs can be exposed to a relatively high level of scattered radiation as the radiation in produced from scatter of the un attenuated beam from the bottom of the patient couch. The routine monitoring of extremity doses in interventional radiology is difficult due to several factors. Firstly a wide range of interventional procedures in undertaken in every radiology department, and these procedures require many different techniques, equipment and skills. This means that the position the radiologist adopts in relation to scattering medium and therefore their exposure, depends heavily on the type of procedure. As the hands which manipulate the catheters within the patient are often located close to the patients side and to the area under irradiation, the distribution of dose across the hands can be variable, with very high localised doses, making routine monitoring difficult. The purpose of this study was to determine the magnitude and distribution of dose to the hands and legs of interventional radiologists carrying out a wide range of both diagnostic and therapeutic interventional procedures. To ascertain the most effective method of monitoring the highest dose in accordance with the Basic safety standards

35 Years of Experience From the American Association for Women Radiologists: Increasing the Visibility of Women in Radiology.

Science.gov (United States)

Spalluto, Lucy B; Arleo, Elizabeth K; Macura, Katarzyna J; Rumack, Carol M

2017-03-01

Women radiologists remain in minority, unchanged for the past several decades. In 1981, the American Association for Women Radiologists (AAWR) was founded to address the problems that women radiologists were experiencing in being subordinate to male radiologists in the workplace and at the national level in organizations with respect to political power and financial compensation, as well as additional issues unique to women in radiology. The AAWR defined goals to meet the needs of women in radiology: improve the visibility of women radiologists, advance the professional and academic standing of women in radiology, and identify and address issues faced by women in radiology. AAWR efforts have included providing opportunities for career development and award recognition, hosting educational programs at national meetings, and publishing numerous manuscripts on issues faced by women in radiology. The AAWR recognizes that although there has been significant progress in the standing of women in radiology over the past 35 years, there is much room for improvement. The AAWR will continue to advocate for the needs of women in radiology. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Accuracy requirements in radiotherapy treatment planning

International Nuclear Information System (INIS)

Buzdar, S. A.; Afzal, M.; Nazir, A.; Gadhi, M. A.

2013-01-01

Radiation therapy attempts to deliver ionizing radiation to the tumour and can improve the survival chances and/or quality of life of patients. There are chances of errors and uncertainties in the entire process of radiotherapy that may affect the accuracy and precision of treatment management and decrease degree of conformation. All expected inaccuracies, like radiation dose determination, volume calculation, complete evaluation of the full extent of the tumour, biological behaviour of specific tumour types, organ motion during radiotherapy, imaging, biological/molecular uncertainties, sub-clinical diseases, microscopic spread of the disease, uncertainty in normal tissue responses and radiation morbidity need sound appreciation. Conformity can be increased by reduction of such inaccuracies. With the yearly increase in computing speed and advancement in other technologies the future will provide the opportunity to optimize a greater number of variables and reduce the errors in the treatment planning process. In multi-disciplined task of radiotherapy, efforts are needed to overcome the errors and uncertainty, not only by the physicists but also by radiologists, pathologists and oncologists to reduce molecular and biological uncertainties. The radiation therapy physics is advancing towards an optimal goal that is definitely to improve accuracy where necessary and to reduce uncertainty where possible. (author)

Canadian Association of Radiologists White Paper on Artificial Intelligence in Radiology.

Science.gov (United States)

Tang, An; Tam, Roger; Cadrin-Chênevert, Alexandre; Guest, Will; Chong, Jaron; Barfett, Joseph; Chepelev, Leonid; Cairns, Robyn; Mitchell, J Ross; Cicero, Mark D; Poudrette, Manuel Gaudreau; Jaremko, Jacob L; Reinhold, Caroline; Gallix, Benoit; Gray, Bruce; Geis, Raym

2018-05-01

Artificial intelligence (AI) is rapidly moving from an experimental phase to an implementation phase in many fields, including medicine. The combination of improved availability of large datasets, increasing computing power, and advances in learning algorithms has created major performance breakthroughs in the development of AI applications. In the last 5 years, AI techniques known as deep learning have delivered rapidly improving performance in image recognition, caption generation, and speech recognition. Radiology, in particular, is a prime candidate for early adoption of these techniques. It is anticipated that the implementation of AI in radiology over the next decade will significantly improve the quality, value, and depth of radiology's contribution to patient care and population health, and will revolutionize radiologists' workflows. The Canadian Association of Radiologists (CAR) is the national voice of radiology committed to promoting the highest standards in patient-centered imaging, lifelong learning, and research. The CAR has created an AI working group with the mandate to discuss and deliberate on practice, policy, and patient care issues related to the introduction and implementation of AI in imaging. This white paper provides recommendations for the CAR derived from deliberations between members of the AI working group. This white paper on AI in radiology will inform CAR members and policymakers on key terminology, educational needs of members, research and development, partnerships, potential clinical applications, implementation, structure and governance, role of radiologists, and potential impact of AI on radiology in Canada. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Accuracy Improvement of Real-Time Location Tracking for Construction Workers

Directory of Open Access Journals (Sweden)

Hyunsoo Kim

2018-05-01

Full Text Available Extensive research has been conducted on the real-time locating system (RTLS for tracking construction components, including workers, equipment, and materials, in order to improve construction performance (e.g., productivity improvement or accident prevention. In order to prevent safety accidents and make more sustainable construction job sites, the higher accuracy of RTLS is required. To improve the accuracy of RTLS in construction projects, this paper presents a RTLS using radio frequency identification (RFID. For this goal, this paper develops a location tracking error mitigation algorithm and presents the concept of using assistant tags. The applicability and effectiveness of the developed RTLS are tested under eight different construction environments and the test results confirm the system’s strong potential for improving the accuracy of real-time location tracking in construction projects, thus enhancing construction performance.

Does radiation exposure produce a protective effect among radiologists

International Nuclear Information System (INIS)

Matanoski, G.M.; Sternberg, A.; Elliott, E.A.

1987-01-01

The mortality experience of radiologists compared to that of other physician specialists demonstrates an increased risk of cancer deaths as well as deaths from all causes among physicians practicing in the early years of this century. However, for the radiologists who joined specialty societies after 1940, the age pattern of deaths has changed. Whereas among early entrants, young radiologists had higher mortality rates than those of other specialists; among later entrants, the young radiologists have lower mortality. However, as these later-entrant radiologists age, their rates appear to exceed those of other specialists. Although the level of radiation exposure is unknown, physicians in more recent years usually have lower cumulative doses. Lower radiation exposure may be one of a number of possible explanatory factors for the cross-over from protected to higher risk status as these physicians age

Observer agreement in the reporting of knee and lumbar spine magnetic resonance (MR) imaging examinations: Selectively trained MR radiographers and consultant radiologists compared with an index radiologist

Energy Technology Data Exchange (ETDEWEB)

Brealey, S., E-mail: stephen.brealey@york.ac.uk [Department of Health Sciences, University of York, York YO10 5DD (United Kingdom); Piper, K., E-mail: keith.piper@canterbury.ac.uk [Department of Allied Health Professions, Canterbury Christ Church University, Canterbury, Kent CT1 1QU (United Kingdom); King, D., E-mail: david.g.king@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom); Bland, M., E-mail: martin.bland@york.ac.uk [Department of Health Sciences, University of York, York YO10 5DD (United Kingdom); Caddick, J., E-mail: Julie.Caddick@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom); Campbell, P., E-mail: peter.campbell@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom); Gibbon, A., E-mail: anthony.j.gibbon@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom); Highland, A., E-mail: Adrian.Highland@sth.nhs.uk [Sheffield Teaching Hospitals, Herries Road, Sheffield S5 7AU (United Kingdom); Jenkins, N., E-mail: neil.jenkins@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom); Petty, D., E-mail: daniel.petty@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom); Warren, D., E-mail: david.warren@york.nhs.uk [York Hospital, Wigginton Road, York YO31 8HE (United Kingdom)

2013-10-01

Purpose: To assess agreement between trained radiographers and consultant radiologists compared with an index radiologist when reporting on magnetic resonance imaging (MRI) examinations of the knee and lumbar spine and to examine the subsequent effect of discordant reports on patient management and outcome. Methods: At York Hospital two MR radiographers, two consultant radiologists and an index radiologist reported on a prospective, random sample of 326 MRI examinations. The radiographers reported in clinical practice conditions and the radiologists during clinical practice. An independent consultant radiologist compared these reports with the index radiologist report for agreement. Orthopaedic surgeons then assessed whether the discordance between reports was clinically important. Results: Overall observer agreement with the index radiologist was comparable between observers and ranged from 54% to 58%; for the knee it was 46–57% and for the lumbar spine was 56–66%. There was a very small observed difference of 0.6% (95% CI −11.9 to 13.0) in mean agreement between the radiographers and radiologists (P = 0.860). For the knee, lumbar spine and overall, radiographers’ discordant reports, when compared with the index radiologist, were less likely to have a clinically important effect on patient outcome than the radiologists’ discordant reports. Less than 10% of observer's reports were sufficiently discordant with the index radiologist's reports to be clinically important. Conclusion: Carefully selected MR radiographers with postgraduate education and training reported in clinical practice conditions on specific MRI examinations of the knee and lumbar spine to a level of agreement comparable with non-musculoskeletal consultant radiologists.

Observer agreement in the reporting of knee and lumbar spine magnetic resonance (MR) imaging examinations: Selectively trained MR radiographers and consultant radiologists compared with an index radiologist

International Nuclear Information System (INIS)

Brealey, S.; Piper, K.; King, D.; Bland, M.; Caddick, J.; Campbell, P.; Gibbon, A.; Highland, A.; Jenkins, N.; Petty, D.; Warren, D.

2013-01-01

Purpose: To assess agreement between trained radiographers and consultant radiologists compared with an index radiologist when reporting on magnetic resonance imaging (MRI) examinations of the knee and lumbar spine and to examine the subsequent effect of discordant reports on patient management and outcome. Methods: At York Hospital two MR radiographers, two consultant radiologists and an index radiologist reported on a prospective, random sample of 326 MRI examinations. The radiographers reported in clinical practice conditions and the radiologists during clinical practice. An independent consultant radiologist compared these reports with the index radiologist report for agreement. Orthopaedic surgeons then assessed whether the discordance between reports was clinically important. Results: Overall observer agreement with the index radiologist was comparable between observers and ranged from 54% to 58%; for the knee it was 46–57% and for the lumbar spine was 56–66%. There was a very small observed difference of 0.6% (95% CI −11.9 to 13.0) in mean agreement between the radiographers and radiologists (P = 0.860). For the knee, lumbar spine and overall, radiographers’ discordant reports, when compared with the index radiologist, were less likely to have a clinically important effect on patient outcome than the radiologists’ discordant reports. Less than 10% of observer's reports were sufficiently discordant with the index radiologist's reports to be clinically important. Conclusion: Carefully selected MR radiographers with postgraduate education and training reported in clinical practice conditions on specific MRI examinations of the knee and lumbar spine to a level of agreement comparable with non-musculoskeletal consultant radiologists

Testing of the assisting software for radiologists analysing head CT images: lessons learned.

Science.gov (United States)

Martynov, Petr; Mitropolskii, Nikolai; Kukkola, Katri; Gretsch, Monika; Koivisto, Vesa-Matti; Lindgren, Ilkka; Saunavaara, Jani; Reponen, Jarmo; Mäkynen, Anssi

2017-12-11

Assessing a plan for user testing and evaluation of the assisting software developed for radiologists. Test plan was assessed in experimental testing, where users performed reporting on head computed tomography studies with the aid of the software developed. The user testing included usability tests, questionnaires, and interviews. In addition, search relevance was assessed on the basis of user opinions. The testing demonstrated weaknesses in the initial plan and enabled improvements. Results showed that the software has acceptable usability level but some minor fixes are needed before larger-scale pilot testing. The research also proved that it is possible even for radiologists with under a year's experience to perform reporting of non-obvious cases when assisted by the software developed. Due to the small number of test users, it was impossible to assess effects on diagnosis quality. The results of the tests performed showed that the test plan designed is useful, and answers to the key research questions should be forthcoming after testing with more radiologists. The preliminary testing revealed opportunities to improve test plan and flow, thereby illustrating that arranging preliminary test sessions prior to any complex scenarios is beneficial.

Logistics of Three-dimensional Printing: Primer for Radiologists.

Science.gov (United States)

Hodgdon, Taryn; Danrad, Raman; Patel, Midhir J; Smith, Stacy E; Richardson, Michael L; Ballard, David H; Ali, Sayed; Trace, Anthony Paul; DeBenedectis, Carolynn M; Zygmont, Matthew E; Lenchik, Leon; Decker, Summer J

2018-01-01

The Association of University Radiologists Radiology Research Alliance Task Force on three-dimensional (3D) printing presents a review of the logistic considerations for establishing a clinical service using this new technology, specifically focused on implications for radiology. Specific topics include printer selection for 3D printing, software selection, creating a 3D model for printing, providing a 3D printing service, research directions, and opportunities for radiologists to be involved in 3D printing. A thorough understanding of the technology and its capabilities is necessary as the field of 3D printing continues to grow. Radiologists are in the unique position to guide this emerging technology and its use in the clinical arena. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Reject analysis: A comparison of radiographer and radiologist perceptions of image quality

International Nuclear Information System (INIS)

Mount, J.

2016-01-01

This study explores the potential differences in perceptions of image quality between radiographers and radiologists in a large UK hospital and the subsequent impact this has on image rejection. Image rejection, while sometimes necessary, often leads to an increased radiation dose to the patient due to the need to repeat. Moreover, this translates into increased waiting times, departmental costs, and lower patient satisfaction. Adopting a mixed methods approach, this paper first seeks to quantify the differences in radiographer and radiologist perceptions and second establish the underlying causes of such differences through a quantitative and qualitative investigation respectively. Using a standardized psychometric scale of a GP lateral knee, the study reveals significant differences in the perceptions of quality and rejection rates between radiographers and radiologists driven by a conflict in the evaluation criteria used. The study has significant implications for improving departmental performance and proposes a potential solution for reducing reject rates and image repeats. - Highlights: • Significant differences are found to exist in perceptions of image quality. • Differences in perceptions of image quality directly influence reject rates. • Radiographers judge images on technical criteria. • Radiologists judge images on diagnostic criteria. • Results suggest better communication could reduce reject rates.

MACRA, MIPS, and the New Medicare Quality Payment Program: An Update for Radiologists.

Science.gov (United States)

Rosenkrantz, Andrew B; Nicola, Gregory N; Allen, Bibb; Hughes, Danny R; Hirsch, Joshua A

2017-03-01

The Medicare Access and CHIP Reauthorization Act (MACRA) of 2015 advances the goal of tying Medicare payments to quality and value. In April 2016, CMS published an initial proposed rule for MACRA, renaming it the Quality Payment Program (QPP). Under QPP, clinicians receive payments through either advanced alternative payment models or the Merit-Based Incentive Payment System (MIPS), a consolidation of existing federal performance programs that applies positive or negative adjustments to fee-for-service payments. Most physicians will participate in MIPS. This review highlights implications of the QPP and MIPS for radiologists. Although MIPS incorporates radiology-specific quality measures, radiologists will also be required to participate in other practice improvement activities, including patient engagement. Recognizing physicians' unique practice patterns, MIPS will provide special considerations in performance evaluation for physicians with limited face-to-face patient interaction. Although such considerations will affect radiologists' likelihood of success under QPP, many practitioners will be ineligible for the considerations under currently proposed criteria. Reporting using qualified clinical data registries will benefit radiologists' performance by allowing expanded arrays of MIPS and non-MIPS specialty-specific measures. A group practice reporting option will substantially reduce administrative burden but introduce new challenges by requiring uniform determination of patient-facing status and performance measurement for all of the group's physicians (diagnostic radiologists, interventional radiologists, and nonradiologists) under the same taxpayer identification number. Given that the initial MIPS performance period begins in 2017, radiologists must begin preparing for QPP and taking actions to ensure their future success under this new quality-based payment system. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights

Concept Mapping Improves Metacomprehension Accuracy among 7th Graders

Science.gov (United States)

Redford, Joshua S.; Thiede, Keith W.; Wiley, Jennifer; Griffin, Thomas D.

2012-01-01

Two experiments explored concept map construction as a useful intervention to improve metacomprehension accuracy among 7th grade students. In the first experiment, metacomprehension was marginally better for a concept mapping group than for a rereading group. In the second experiment, metacomprehension accuracy was significantly greater for a…

Improved mammographic interpretation of masses using computer-aided diagnosis

International Nuclear Information System (INIS)

Leichter, I.; Fields, S.; Novak, B.; Nirel, R.; Bamberger, P.; Lederman, R.; Buchbinder, S.

2000-01-01

The aim of this study was to evaluate the effectiveness of computerized image enhancement, to investigate criteria for discriminating benign from malignant mammographic findings by computer-aided diagnosis (CAD), and to test the role of quantitative analysis in improving the accuracy of interpretation of mass lesions. Forty sequential mammographically detected mass lesions referred for biopsy were digitized at high resolution for computerized evaluation. A prototype CAD system which included image enhancement algorithms was used for a better visualization of the lesions. Quantitative features which characterize the spiculation were automatically extracted by the CAD system for a user-defined region of interest (ROI). Reference ranges for malignant and benign cases were acquired from data generated by 214 known retrospective cases. The extracted parameters together with the reference ranges were presented to the radiologist for the analysis of 40 prospective cases. A pattern recognition scheme based on discriminant analysis was trained on the 214 retrospective cases, and applied to the prospective cases. Accuracy of interpretation with and without the CAD system, as well as the performance of the pattern recognition scheme, were analyzed using receiver operating characteristics (ROC) curves. A significant difference (p z ) increased significantly (p z for the results of the pattern recognition scheme was higher (0.95). The results indicate that there is an improved accuracy of diagnosis with the use of the mammographic CAD system above that of the unassisted radiologist. Our findings suggest that objective quantitative features extracted from digitized mammographic findings may help in differentiating between benign and malignant masses, and can assist the radiologist in the interpretation of mass lesions. (orig.)

Impact of a voice recognition system on report cycle time and radiologist reading time

Science.gov (United States)

Melson, David L.; Brophy, Robert; Blaine, G. James; Jost, R. Gilbert; Brink, Gary S.

1998-07-01

Because of its exciting potential to improve clinical service, as well as reduce costs, a voice recognition system for radiological dictation was recently installed at our institution. This system will be clinically successful if it dramatically reduces radiology report turnaround time without substantially affecting radiologist dictation and editing time. This report summarizes an observer study currently under way in which radiologist reporting times using the traditional transcription system and the voice recognition system are compared. Four radiologists are observed interpreting portable intensive care unit (ICU) chest examinations at a workstation in the chest reading area. Data are recorded with the radiologists using the transcription system and using the voice recognition system. The measurements distinguish between time spent performing clerical tasks and time spent actually dictating the report. Editing time and the number of corrections made are recorded. Additionally, statistics are gathered to assess the voice recognition system's impact on the report cycle time -- the time from report dictation to availability of an edited and finalized report -- and the length of reports.

Statewide Quality Improvement Initiative to Reduce Early Elective Deliveries and Improve Birth Registry Accuracy.

Science.gov (United States)

Kaplan, Heather C; King, Eileen; White, Beth E; Ford, Susan E; Fuller, Sandra; Krew, Michael A; Marcotte, Michael P; Iams, Jay D; Bailit, Jennifer L; Bouchard, Jo M; Friar, Kelly; Lannon, Carole M

2018-04-01

To evaluate the success of a quality improvement initiative to reduce early elective deliveries at less than 39 weeks of gestation and improve birth registry data accuracy rapidly and at scale in Ohio. Between February 2013 and March 2014, participating hospitals were involved in a quality improvement initiative to reduce early elective deliveries at less than 39 weeks of gestation and improve birth registry data. This initiative was designed as a learning collaborative model (group webinars and a single face-to-face meeting) and included individual quality improvement coaching. It was implemented using a stepped wedge design with hospitals divided into three balanced groups (waves) participating in the initiative sequentially. Birth registry data were used to assess hospital rates of nonmedically indicated inductions at less than 39 weeks of gestation. Comparisons were made between groups participating and those not participating in the initiative at two time points. To measure birth registry accuracy, hospitals conducted monthly audits comparing birth registry data with the medical record. Associations were assessed using generalized linear repeated measures models accounting for time effects. Seventy of 72 (97%) eligible hospitals participated. Based on birth registry data, nonmedically indicated inductions at less than 39 weeks of gestation declined in all groups with implementation (wave 1: 6.2-3.2%, Pinitiative, they saw significant decreases in rates of early elective deliveries as compared with wave 3 (control; P=.018). All waves had significant improvement in birth registry accuracy (wave 1: 80-90%, P=.017; wave 2: 80-100%, P=.002; wave 3: 75-100%, Pinitiative enabled statewide spread of change strategies to decrease early elective deliveries and improve birth registry accuracy over 14 months and could be used for rapid dissemination of other evidence-based obstetric care practices across states or hospital systems.

Evaluation of radiographers’ mammography screen-reading accuracy in Australia

International Nuclear Information System (INIS)

Debono, Josephine C; Poulos, Ann E; Houssami, Nehmat; Turner, Robin M; Boyages, John

2015-01-01

This study aimed to evaluate the accuracy of radiographers’ screen-reading mammograms. Currently, radiologist workforce shortages may be compromising the BreastScreen Australia screening program goal to detect early breast cancer. The solution to a similar problem in the United Kingdom has successfully encouraged radiographers to take on the role as one of two screen-readers. Prior to consideration of this strategy in Australia, educational and experiential differences between radiographers in the United Kingdom and Australia emphasise the need for an investigation of Australian radiographers’ screen-reading accuracy. Ten radiographers employed by the Westmead Breast Cancer Institute with a range of radiographic (median = 28 years), mammographic (median = 13 years) and BreastScreen (median = 8 years) experience were recruited to blindly and independently screen-read an image test set of 500 mammograms, without formal training. The radiographers indicated the presence of an abnormality using BI-RADS®. Accuracy was determined by comparison with the gold standard of known outcomes of pathology results, interval matching and client 6-year follow-up. Individual sensitivity and specificity levels ranged between 76.0% and 92.0%, and 74.8% and 96.2% respectively. Pooled screen-reader accuracy across the radiographers estimated sensitivity as 82.2% and specificity as 89.5%. Areas under the reading operating characteristic curve ranged between 0.842 and 0.923. This sample of radiographers in an Australian setting have adequate accuracy levels when screen-reading mammograms. It is expected that with formal screen-reading training, accuracy levels will improve, and with support, radiographers have the potential to be one of the two screen-readers in the BreastScreen Australia program, contributing to timeliness and improved program outcomes

Evaluation of radiographers’ mammography screen-reading accuracy in Australia

Energy Technology Data Exchange (ETDEWEB)

Debono, Josephine C, E-mail: josephine.debono@bci.org.au [Westmead Breast Cancer Institute, Westmead, New South Wales (Australia); Poulos, Ann E [Discipline of Medical Radiation Sciences, Faculty of Health Sciences, University of Sydney, Lidcombe, New South Wales (Australia); Houssami, Nehmat [Screening and Test Evaluation Program, School of Public Health (A27), Sydney Medical School, University of Sydney, Sydney, New South Wales (Australia); Turner, Robin M [School of Public Health and Community Medicine, University of New South Wales, Sydney, New South Wales (Australia); Boyages, John [Macquarie University Cancer Institute, Macquarie University Hospital, Australian School of Advanced Medicine, Macquarie University, Sydney, New South Wales (Australia); Westmead Breast Cancer Institute, Westmead, New South Wales (Australia)

2015-03-15

This study aimed to evaluate the accuracy of radiographers’ screen-reading mammograms. Currently, radiologist workforce shortages may be compromising the BreastScreen Australia screening program goal to detect early breast cancer. The solution to a similar problem in the United Kingdom has successfully encouraged radiographers to take on the role as one of two screen-readers. Prior to consideration of this strategy in Australia, educational and experiential differences between radiographers in the United Kingdom and Australia emphasise the need for an investigation of Australian radiographers’ screen-reading accuracy. Ten radiographers employed by the Westmead Breast Cancer Institute with a range of radiographic (median = 28 years), mammographic (median = 13 years) and BreastScreen (median = 8 years) experience were recruited to blindly and independently screen-read an image test set of 500 mammograms, without formal training. The radiographers indicated the presence of an abnormality using BI-RADS®. Accuracy was determined by comparison with the gold standard of known outcomes of pathology results, interval matching and client 6-year follow-up. Individual sensitivity and specificity levels ranged between 76.0% and 92.0%, and 74.8% and 96.2% respectively. Pooled screen-reader accuracy across the radiographers estimated sensitivity as 82.2% and specificity as 89.5%. Areas under the reading operating characteristic curve ranged between 0.842 and 0.923. This sample of radiographers in an Australian setting have adequate accuracy levels when screen-reading mammograms. It is expected that with formal screen-reading training, accuracy levels will improve, and with support, radiographers have the potential to be one of the two screen-readers in the BreastScreen Australia program, contributing to timeliness and improved program outcomes.

'Whatever happened to the class of 2000?' An outcome survey of potential interventional radiologists

International Nuclear Information System (INIS)

Nicholson, A.A.; Adam, A.

2006-01-01

Objectives: To find out what final career choices were made by trainee doctors who had indicated a strong interest in pursuing a career in interventional radiology and to establish the reasons behind their final career choice. Methods: Eighty-eight doctors who attended a meeting in 2000 designed to promote interventional radiology as a career were questioned as to whether the meeting influenced their potential career choices and then further surveyed via postal questionnaire 5 years later to find out their eventual career choices. Of the 88 doctors who attended, 56 were radiology trainees and 32 were training in either medical or surgical specialties. There were 25 women and 63 men. Results: Five years after the meeting, six are now interventional radiologists (6.8%) though four of these are still in a 6th year interventional radiology fellowship. A further 12 (13.6%) are systems based, predominantly diagnostic radiologists with an interest in intervention. Thirty-two (43.2%) are diagnostic radiologists who undertake little or no therapeutic intervention. Of the 32 non-radiologists who attended the meeting only three entered radiology and are still in training. Conclusions: Interventional radiology is a popular initial career choice amongst trainee doctors. However, only a small number eventually pursue the specialty. If the manpower shortage of interventional radiologists is to be addressed, there needs to be improvements in training, accreditation, career opportunities and working conditions

Breast cancer staging: the role of the radiologist

International Nuclear Information System (INIS)

Trop, I.; David, J.; Lalonde, L.

2005-01-01

The role of the breast radiologist has evolved over the past years, with an increasing involvement in patient care. Improvements in diagnostic technology and surgical techniques allow for better preoperative staging and surgeries with decreased morbidity. This article reviews the elements of investigation that are important to the surgeon and oncologist in optimizing care for the newly diagnosed breast cancer patient, with the 6th edition of the TNM classification of the American Joint Committee on Cancer used as a reference. (author)

Relationships between radiologists and clinicians: Results from three surveys

International Nuclear Information System (INIS)

Dalla Palma, L.; Stacul, F.; Meduri, S.; Geitung, J. Te.

2000-01-01

AIM: To analyse reasons for and the nature of clinico-radiological contacts and their clinical impact. MATERIALS AND METHODS: Three different surveys were performed. (1) Data concerning contacts between staff radiologists (n = 20) and clinicians during 10 consecutive working days were collected; (2) staff clinicians (n = 174) filled in a questionnaire asking for their opinions about relationships with radiologists; (3) staff radiologists collected data about contacts with clinicians related to more urgent/complicated cases. Radiologists assessed the clinical impact of the radiological procedure and of the consultation. RESULTS: (1) During 220 working days 20 radiologists had a mean of 3.95 contacts per day (48.2% personal contacts, 51.8% telephone contacts), amounting to a personal total of 21.65 min per day. These contacts amounted to a total of 7.08 h per day, roughly one whole-time equivalent radiologist. (2) These consultations helped to refine the diagnostic strategy often (12.6%) or sometimes (71.4%) and to alter therapeutic decisions often (10.4%) or sometimes (56.6%). (3) The initial clinical diagnosis was changed in 50% of cases and the therapy was substantially changed on the basis of further radiological investigations and clinical-radiological discussion in 60% of cases. CONCLUSION: Clinical-radiological consultations are time consuming but have a beneficial diagnostic and therapeutic impact. Dalla Palma, L. (2000)

Diagnostic Accuracy of the Volume Rendering Images of Multi-Detector CT for the Detection of Lumbar Transverse Process Fractures

Energy Technology Data Exchange (ETDEWEB)

Lee, Yun Hak; Chun, Tong Jin [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

2012-01-15

To compare the accuracy of three-dimensional computed tomographic (3D CT) volume rendering techniques with axial images of multi-detector row computed tomography to identify lumbar transverse process (LTP) fractures in trauma patients. We retrospectively evaluated 42 patients with back pain as a result of blunt trauma between January and June of 2010. Two radiologists examined the 3D CT volume rendering images independently. The confirmation of a LTP fracture was based on the consensus of the axial images by the two radiologists. The results of 3D CT volume rendering images were compared with the axial images and the diagnostic powers (sensitivity, specificity, and accuracy) were calculated. Seven of the 42 patients had twenty five lumbar transverse process fractures. The diagnostic power of the 3D CT volume rendering technique is as accurate as axial images. Reader 1, sensitivity 96%, specificity 100%, accuracy 99.9%; and Reader 2 sensitivity 100%, specificity 99.8%, accuracy 99.8%. The accordance of the two radiologists was 99.8%. 3D CT volume rendering images can alternate axial images to detect lumbar transverse process fractures with good image quality.

Radiation protection knowledge among radiologists in northwest Spain.

Science.gov (United States)

Macía-Suárez, D; Sánchez-Rodríguez, E

2018-05-16

To estimate radiologistś level of knowledge of and their implication in radioprotection. An anonymous and supervised survey was conducted during a work meeting. Of the 65 questionnaires handed out, 63 were returned. In general, the radiologists surveyed considered their level of knowledge to be low, and it was statistically demonstrated (P = 0.018) that the level of knowledge they believed they had was related to the number of correct answers. The level of knowledge that radiologists believed they had was also related (p knowledge about radiation protection. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Does a Structured Data Collection Form Improve The Accuracy of ...

African Journals Online (AJOL)

and multiple etiologies for similar presentation. Standardized forms may harmonize the initial assessment, improve accuracy of diagnosis and enhance outcomes. Objectives: To determine the extent to which use of a structured data collection form (SDCF) affected the diagnostic accuracy of AAP. Methodology: A before and ...

Radiologists' preferences for just-in-time learning.

Science.gov (United States)

Kahn, Charles E; Ehlers, Kevin C; Wood, Beverly P

2006-09-01

Effective learning can occur at the point of care, when opportunities arise to acquire information and apply it to a clinical problem. To assess interest in point-of-care learning, we conducted a survey to explore radiologists' attitudes and preferences regarding the use of just-in-time learning (JITL) in radiology. Following Institutional Review Board approval, we invited 104 current radiology residents and 86 radiologists in practice to participate in a 12-item Internet-based survey to assess their attitudes toward just-in-time learning. Voluntary participation in the survey was solicited by e-mail; respondents completed the survey on a web-based form. Seventy-nine physicians completed the questionnaire, including 47 radiology residents and 32 radiologists in practice; the overall response rate was 42%. Respondents generally expressed a strong interest for JITL: 96% indicated a willingness to try such a system, and 38% indicated that they definitely would use a JITL system. They expressed a preference for learning interventions of 5-10 min in length. Current and recent radiology trainees have expressed a strong interest in just-in-time learning. The information from this survey should be useful in pursuing the design of learning interventions and systems for delivering just-in-time learning to radiologists.

Business of radiology: financial fundamentals for radiologists.

Science.gov (United States)

Medverd, Jonathan R; Prabhu, Somnath J; Lam, Diana L

2013-11-01

The purposes of this article are to provide a primer on financial statements and to review several financial concepts that are at the foundation of the business of medicine. For radiologists to effectively contribute to the leadership and management of their practices, it is imperative that they understand the business aspects of radiology. Radiologists' understanding and participation in practice management may also facilitate job satisfaction and assist the provision of optimal patient care.

Teleradiology in Southeast Iran: Evaluating the Views of Senior Executives and Radiologists.

Science.gov (United States)

Sadoughi, Farahnaz; Erfannia, Leila; Sancholi, Mahboobe; Salmani, Fatemeh; Sarsarshahi, Aida

Teleradiology is considered as one of the important forms of telemedicine. Positive views of the users and providers of these services play an important role in its successful implementations. The aim of this study was to investigate the views of radiologists used in the radiology departments of teaching hospitals in the Zahedan University of Medical Sciences through teleradiology, as well as evaluate the executive possibility of teleradiology in these hospitals by the views of chief executive officer and comparison between these two views. The current cross-sectional research was performed in 2014 at Zahedan teaching hospitals. The views of 13 chief executive officers on the possibility of the execution of teleradiology and 26 radiologists on the teleradiology process were evaluated by means of two valid and reliable questionnaires. The results of the research revealed that most of the radiologists had knowledge of and positive opinions about teleradiology. Conversely, the view by chief executive officers was that implementation of these processes was not possible in the studied hospitals. Dealing with some issues including data security, controlling or restricting access to clinical information of patients during the process of teleradiology, the possibility of legal protection for the participating radiologists, constitution of executive teams in the organization along with the financial supports, and, subsequently, invitation of the supports from the chief executive officers as the main sponsors of teleradiology implementation in the teaching hospitals are all guidelines for improvement of the successful implementation of teleradiology.

PACS administrators' and radiologists' perspective on the importance of features for PACS selection.

Science.gov (United States)

Joshi, Vivek; Narra, Vamsi R; Joshi, Kailash; Lee, Kyootai; Melson, David

2014-08-01

Picture archiving and communication systems (PACS) play a critical role in radiology. This paper presents the criteria important to PACS administrators for selecting a PACS. A set of criteria are identified and organized into an integrative hierarchical framework. Survey responses from 48 administrators are used to identify the relative weights of these criteria through an analytical hierarchy process. The five main dimensions for PACS selection in order of importance are system continuity and functionality, system performance and architecture, user interface for workflow management, user interface for image manipulation, and display quality. Among the subdimensions, the highest weights were assessed for security, backup, and continuity; tools for continuous performance monitoring; support for multispecialty images; and voice recognition/transcription. PACS administrators' preferences were generally in line with that of previously reported results for radiologists. Both groups assigned the highest priority to ensuring business continuity and preventing loss of data through features such as security, backup, downtime prevention, and tools for continuous PACS performance monitoring. PACS administrators' next high priorities were support for multispecialty images, image retrieval speeds from short-term and long-term storage, real-time monitoring, and architectural issues of compatibility and integration with other products. Thus, next to ensuring business continuity, administrators' focus was on issues that impact their ability to deliver services and support. On the other hand, radiologists gave high priorities to voice recognition, transcription, and reporting; structured reporting; and convenience and responsiveness in manipulation of images. Thus, radiologists' focus appears to be on issues that may impact their productivity, effort, and accuracy.

Prostatic MR imaging. Accuracy in differentiating cancer from other prostatic disorders

Energy Technology Data Exchange (ETDEWEB)

Ikonen, S.; Kivisaari, L.; Tervahartiala, P. [Helsinki Univ. Central Hospital (Finland). Dept of Radiology; Vehmas, T. [Finnish Inst. of Occupational Health, Helsinki (Finland); Taari, K.; Rannikko, S. [Helsinki Univ. Central Hospital (Finland). Dept of Urology

2001-03-01

Purpose: We assessed the accuracy of MR imaging in differentiating between cancer and other prostatic disorders, and evaluated the diagnostic criteria for various prostatic diseases. Material and Methods: A total of 74 endorectal coil MR studies were performed on 72 patients. Twenty patients had prostatic cancer, 20 benign prostatic hyperplasia (BPH), 4 acute bacterial prostatitis, 5 chronic bacterial prostatitis (2 also belonging to the previous category), 19 chronic non-bacterial prostatitis/chronic pelvic pain syndrome, and 6 were symptomless voluntary controls. All studies were interpreted by two experienced radiologists in random order. Radiologists were blinded to all clinical data including the age of the patients. Based on MR findings, both radiologists filled in a form covering diagnostic criteria and diagnosis. Results: Accuracy in diagnosing prostate cancer was 74%. Sensitivity was 50% and specificity 83%, and positive and negative predictive values were 53 and 82%, respectively. Bacterial prostatitis showed some features similar to carcinoma. Abundant BPH rendered cancer detection more difficult. No diagnostic criterion was clearly better than the others. Interobserver agreement on the MR diagnosis ranged from moderate to good. Conclusion: Without knowledge of accurate clinical data, MR seems to be too insensitive in detecting prostate cancer to be used as a primary diagnostic tool.

Can Radiologists Learn From Airport Baggage Screening?: A Survey About Using Fictional Patients for Quality Assurance.

Science.gov (United States)

Phelps, Andrew; Callen, Andrew L; Marcovici, Peter; Naeger, David M; Mongan, John; Webb, Emily M

2018-02-01

For both airport baggage screeners and radiologists, low target prevalence is associated with low detection rate, a phenomenon known as "prevalence effect." In airport baggage screening, the target prevalence is artificially increased with fictional weapons that are digitally superimposed on real baggage. This strategy improves the detection rate of real weapons and also allows airport supervisors to monitor screener performance. A similar strategy using fictional patients could be applied in radiology. The purpose of this study was twofold: (1) to review the psychophysics literature regarding low target prevalence and (2) to survey radiologists' attitudes toward using fictional patients as a quality assurance tool. We reviewed the psychophysics literature on low target prevalence and airport x-ray baggage screeners. An online survey was e-mailed to all members of the Association of University Radiologists to determine their attitudes toward using fictional patients in radiology. Of the 1503 Association of University Radiologists member recipients, there were 153 respondents (10% response rate). When asked whether the use of fictional patients was a good idea, the responses were as follows: disagree (44%), neutral (25%), and agree (31%). The most frequent concern was the time taken away from doing clinical work (89% of the respondents). The psychophysics literature supports the use of fictional targets to mitigate the prevalence effect. However, the use of fictional patients is not a popular idea among academic radiologists. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Is diagnostic accuracy for detecting pulmonary nodules in chest CT reduced after a long day of reading?

Science.gov (United States)

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.

Improving Accuracy for Image Fusion in Abdominal Ultrasonography

Directory of Open Access Journals (Sweden)

Caroline Ewertsen

2012-08-01

Full Text Available Image fusion involving real-time ultrasound (US is a technique where previously recorded computed tomography (CT or magnetic resonance images (MRI are reformatted in a projection to fit the real-time US images after an initial co-registration. The co-registration aligns the images by means of common planes or points. We evaluated the accuracy of the alignment when varying parameters as patient position, respiratory phase and distance from the co-registration points/planes. We performed a total of 80 co-registrations and obtained the highest accuracy when the respiratory phase for the co-registration procedure was the same as when the CT or MRI was obtained. Furthermore, choosing co-registration points/planes close to the area of interest also improved the accuracy. With all settings optimized a mean error of 3.2 mm was obtained. We conclude that image fusion involving real-time US is an accurate method for abdominal examinations and that the accuracy is influenced by various adjustable factors that should be kept in mind.

Investigating the Link Between Radiologists Gaze, Diagnostic Decision, and Image Content

Energy Technology Data Exchange (ETDEWEB)

Tourassi, Georgia [ORNL; Voisin, Sophie [ORNL; Paquit, Vincent C [ORNL; Krupinski, Elizabeth [University of Arizona

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 pooling 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.

Your Radiologist Explains Nuclear Medicine

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Full Text Available ... Disorders Video: The Basketball Game: An MRI Story Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org Hello! I’m Dr. Ramji ...

Cephalometric landmark variability among orthodontists and dentomaxillofacial radiologists: a comparative study

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Durao, Ana Paula Reis; Ferreira, Afonso P. [Dept.of Faculty of Dental Medicine, University of Porto, Porto (Portugal); Morosolli, Aline [Dept.of Surgery, Dentistry School, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul (Brazil); Pittayapat, Pisha [Dept.of Radiology, Faculty of Dentistry, Chulalongkorn University, Bangkok (Thailand); Bolstad, Napat [Dept.of Clinical Dentistry, Faculty of Health Science, UiT The Arctic University of Norway, Tromso (Norway); Jacobs, Reinhilde [Dept.of Oral Imaging Center, OMFS-IMPATH Research Group, Dept. of Imaging and Pathology, Faculty of Medicine, University of Leuven, Leuven (Belgium)

2015-12-15

The aim this study was to compare the accuracy of orthodontists and dentomaxillofacial radiologists in identifying 17 commonly used cephalometric landmarks, and to determine the extent of variability associated with each of those landmarks. Twenty digital lateral cephalometric radiographs were evaluated by two groups of dental specialists, and 17 cephalometric landmarks were identified. The x and y coordinates of each landmark were recorded. The mean value for each landmark was considered the best estimate and used as the standard. Variation in measurements of the distance between landmarks and measurements of the angles associated with certain landmarks was also assessed by a subset of two observers, and intraobserver and interobserver agreement were evaluated. Intraclass correlation coefficients were excellent for intraobserver agreement, but only good for interobserver agreement. The least reliable landmark for orthodontists was the gnathion (Gn) point (standard deviation [SD], 5.92 mm), while the orbitale (Or) was the least reliable landmark (SD, 4.41 mm) for dentomaxillofacial radiologists. Furthermore, the condylion (Co)-Gn plane was the least consistent (SD, 4.43 mm). We established that some landmarks were not as reproducible as others, both horizontally and vertically. The most consistently identified landmark in both groups was the lower incisor border, while the least reliable points were Co, Gn, Or, and the anterior nasal spine. Overall, a lower level of reproducibility in the identification of cephalometric landmarks was observed among orthodontists.

Cephalometric landmark variability among orthodontists and dentomaxillofacial radiologists: a comparative study

International Nuclear Information System (INIS)

Durao, Ana Paula Reis; Ferreira, Afonso P.; Morosolli, Aline; Pittayapat, Pisha; Bolstad, Napat; Jacobs, Reinhilde

2015-01-01

The aim this study was to compare the accuracy of orthodontists and dentomaxillofacial radiologists in identifying 17 commonly used cephalometric landmarks, and to determine the extent of variability associated with each of those landmarks. Twenty digital lateral cephalometric radiographs were evaluated by two groups of dental specialists, and 17 cephalometric landmarks were identified. The x and y coordinates of each landmark were recorded. The mean value for each landmark was considered the best estimate and used as the standard. Variation in measurements of the distance between landmarks and measurements of the angles associated with certain landmarks was also assessed by a subset of two observers, and intraobserver and interobserver agreement were evaluated. Intraclass correlation coefficients were excellent for intraobserver agreement, but only good for interobserver agreement. The least reliable landmark for orthodontists was the gnathion (Gn) point (standard deviation [SD], 5.92 mm), while the orbitale (Or) was the least reliable landmark (SD, 4.41 mm) for dentomaxillofacial radiologists. Furthermore, the condylion (Co)-Gn plane was the least consistent (SD, 4.43 mm). We established that some landmarks were not as reproducible as others, both horizontally and vertically. The most consistently identified landmark in both groups was the lower incisor border, while the least reliable points were Co, Gn, Or, and the anterior nasal spine. Overall, a lower level of reproducibility in the identification of cephalometric landmarks was observed among orthodontists

Your Radiologist Explains Nuclear Medicine

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Full Text Available ... by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org Hello! ... d like to talk to you about nuclear medicine. Nuclear medicine offers the potential to identify disease ...

Your Radiologist Explains Nuclear Medicine

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Full Text Available ... An MRI Story Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript ... by a special camera and computer to create images of the inside of your body. If you’ ...

Your Radiologist Explains Nuclear Medicine

Medline Plus

Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Nuclear Medicine Transcript Welcome to Radiology Info dot org ... I’d like to talk to you about nuclear medicine. Nuclear medicine offers the potential to identify ...

Diagnostic accuracy of mammography readers and their memory performance have no correlation with each other

International Nuclear Information System (INIS)

Kok, P.; Cawson, J.N.; Mercuri, V.; Pitman, A.G.; Gledhill, S.; Shnier, D.; Taft, R.; Zentner, L.

2010-01-01

Full text: The study aims to determine if any association exists between visual memory performance and diagnostic accuracy performance in a group of radiologist mammogram readers. Materials and Methods: One hundred proven mammograms (23 with cancers) were grouped into 5 sets of 20 cases, with sets being of equal difficulty. Pairs of sets were presented in 5 reads (40 cases per read, order random) to a panel of 8 radiologist readers (either present or past screening readers, with experience range from 20 years). The readers were asked to either 'clear' or 'call back' cases depending on need for further workup, and at post-baseline reads to indicate whether each case was 'new' or 'old' (i .e. remembered from prior read). Two sets were presented only at baseline (40 cases per reader), and were used to calculate the reader's false recollection rate. Three sets were repeated post-baseline once or twice (100 cases per reader). Reading conditions were standardised. Results: Memory performance differed markedly between readers. The number of correctly remembered cases (of 100 'old' cases) had a median of 10.5 and range of 0-58. The observed number of false recollections (of 40 'totally new' cases) had a median of 2 and range of 0-17. Diagnostic performance measures were mean (range): sensitivity 0.68 (0.54-0.81); specificity 0.82 (0.74-0.91); positive predictive value (PPV) 0.55 (0.500.65); negative predictive value (NPV) 0.89 (0.86-0.93) and accuracy 0.78 (0.76-0.83). Confidence intervals (CIs; 95%) for each reader overlapped for all the diagnostic parameters, indicating a lack of statistically significant difference between the readers at the 5% level. The most sensitive and the most specific reader showed a trend away from each other on sensitivity, specificity, NPV and PPV; their accuracies were 0.76 and 0.82, respectively, and their accuracy 95% CIs overlapped considerably. Correlation analysis by reader showed no association between observed memory performance and

Can Translation Improve EFL Students' Grammatical Accuracy? [

Directory of Open Access Journals (Sweden)

Carol Ebbert-Hübner

2018-01-01

Full Text Available This report focuses on research results from a project completed at Trier University in December 2015 that provides insight into whether a monolingual group of learners can improve their grammatical accuracy and reduce interference mistakes in their English via contrastive analysis and translation instruction and activities. Contrastive analysis and translation (CAT instruction in this setting focusses on comparing grammatical differences between students’ dominant language (German and English, and practice activities where sentences or short texts are translated from German into English. The results of a pre- and post-test administered in the first and final week of a translation class were compared to two other class types: a grammar class which consisted of form-focused instruction but not translation, and a process-approach essay writing class where students received feedback on their written work throughout the semester. The results of our study indicate that with C1 level EAP students, more improvement in grammatical accuracy is seen through teaching with CAT than in explicit grammar instruction or through language feedback on written work alone. These results indicate that CAT does indeed have a place in modern language classes.

CT colonography: effect of computer-aided detection of colonic polyps as a second and concurrent reader for general radiologists with moderate experience in CT colonography

International Nuclear Information System (INIS)

Mang, Thomas; Ringel, Helmut; Weber, Michael; Bogoni, Luca; Anand, Vikram X.; Hermosillo, Gerardo; Raykar, Vikas; Salganicoff, Marcos; Wolf, Matthias; Chandra, Dass; Curtin, Andrew J.; Lev-Toaff, Anna S.; Noah, Ralph; Shaw, Robert; Summerton, Susan; Tappouni, Rafel F.R.; Obuchowski, Nancy A.

2014-01-01

To assess the effectiveness of computer-aided detection (CAD) as a second reader or concurrent reader in helping radiologists who are moderately experienced in computed tomographic colonography (CTC) to detect colorectal polyps. Seventy CTC datasets (34 patients: 66 polyps ≥6 mm; 36 patients: no abnormalities) were retrospectively reviewed by seven radiologists with moderate CTC experience. After primary unassisted evaluation, a CAD second read and, after a time interval of ≥4 weeks, a CAD concurrent read were performed. Areas under the receiver operating characteristic (ROC) curve (AUC), along with per-segment, per-polyp and per-patient sensitivities, and also reading times, were calculated for each reader with and without CAD. Of seven readers, 86 % and 71 % achieved a higher accuracy (segment-level AUC) when using CAD as second and concurrent reader respectively. Average segment-level AUCs with second and concurrent CAD (0.853 and 0.864) were significantly greater (p < 0.0001) than average AUC in the unaided evaluation (0.781). Per-segment, per-polyp, and per-patient sensitivities for polyps ≥6 mm were significantly higher in both CAD reading paradigms compared with unaided evaluation. Second-read CAD reduced readers' average segment and patient specificity by 0.007 and 0.036 (p = 0.005 and 0.011), respectively. CAD significantly improves the sensitivities of radiologists moderately experienced in CTC for polyp detection, both as second reader and concurrent reader. (orig.)

A radiologist's guide to small bowel and multivisceral transplantation

International Nuclear Information System (INIS)

Godfrey, E.M.; Upponi, S.S.; See, T.C.; Cheow, H.K.; Sivaprakasam, R.; Butler, A.J.; Whitley, S.

2013-01-01

This review will describe the indications for the various small bowel containing transplants. The importance of early referral will be highlighted. Radiologists play a central role in assessing these complex patients prior to transplantation. Furthermore, in the postoperative period, radiologists play an important part in diagnosing and treating complications

Accuracy of non assisted glenohumeral joint injection in the office setting

Energy Technology Data Exchange (ETDEWEB)

Sidon, Eliezer, E-mail: eli.sidon@gmail.com [Department of Orthopedics, Rabin Medical Center, Beilinson Campus, Petach Tikva 49100 (Israel); Velkes, Steven, E-mail: velkes@yahoo.com [Department of Orthopedics, Rabin Medical Center, Beilinson Campus, Petach Tikva 49100 (Israel); Shemesh, Shai, E-mail: shai.shemesh@gmail.com [Department of Orthopedics, Rabin Medical Center, Beilinson Campus, Petach Tikva 49100 (Israel); Levy, Jakob, E-mail: Jlevy@clalit.org.il [Department of Imaging, Rabin Medical Center, Beilinson Campus, Petach Tikva 49100 (Israel); Glaser, Ernesto, E-mail: glaser.ernesto@gmail.com [Department of Imaging, Rabin Medical Center, Beilinson Campus, Petach Tikva 49100 (Israel); Kosashvili, Yona, E-mail: yonasofi@gmail.com [Department of Orthopedics, Rabin Medical Center, Beilinson Campus, Petach Tikva 49100 (Israel)

2013-12-01

Purpose: The diagnostic and therapeutic success of shoulder joint injection depends on its accuracy. Two recent studies reported high success (93–96%) for non-imaging-assisted anterior injection in anesthetized patients. This study examined the accuracy of anterior shoulder injection in awake patients under conditions similar to the office setting. Methods: The study group consisted of 166 consecutive patients with shoulder pain who underwent diagnostic magnetic resonance arthrography at a tertiary medical center in 2011–2012. As part of the examination, contrast material was injected into the glenohumeral joint via an anterior approach by a certified musculoskeletal radiologist without any image assistance. Success was defined as contrast material limited to the intra-articular joint on the scan, without scatter to the periauricular tissue. Results: A successful injection was verified by magnetic resonance arthography in 163 patients (98.2%). Conclusions: Non-assisted anterior shoulder injection is highly accurate (98.2%) in the hands of an experienced radiologist, even in awake patients.

Learning linear spatial-numeric associations improves accuracy of memory for numbers

Directory of Open Access Journals (Sweden)

Clarissa Ann Thompson

2016-01-01

Full Text Available Memory for numbers improves with age and experience. One potential source of improvement is a logarithmic-to-linear shift in children’s representations of magnitude. To test this, Kindergartners and second graders estimated the location of numbers on number lines and recalled numbers presented in vignettes (Study 1. Accuracy at number-line estimation predicted memory accuracy on a numerical recall task after controlling for the effect of age and ability to approximately order magnitudes (mapper status. To test more directly whether linear numeric magnitude representations caused improvements in memory, half of children were given feedback on their number-line estimates (Study 2. As expected, learning linear representations was again linked to memory for numerical information even after controlling for age and mapper status. These results suggest that linear representations of numerical magnitude may be a causal factor in development of numeric recall accuracy.

Improvement on Timing Accuracy of LIDAR for Remote Sensing

Science.gov (United States)

Zhou, G.; Huang, W.; Zhou, X.; Huang, Y.; He, C.; Li, X.; Zhang, L.

2018-05-01

The traditional timing discrimination technique for laser rangefinding in remote sensing, which is lower in measurement performance and also has a larger error, has been unable to meet the high precision measurement and high definition lidar image. To solve this problem, an improvement of timing accuracy based on the improved leading-edge timing discrimination (LED) is proposed. Firstly, the method enables the corresponding timing point of the same threshold to move forward with the multiple amplifying of the received signal. Then, timing information is sampled, and fitted the timing points through algorithms in MATLAB software. Finally, the minimum timing error is calculated by the fitting function. Thereby, the timing error of the received signal from the lidar is compressed and the lidar data quality is improved. Experiments show that timing error can be significantly reduced by the multiple amplifying of the received signal and the algorithm of fitting the parameters, and a timing accuracy of 4.63 ps is achieved.

Computer-aided detection of pulmonary embolism: Influence on radiologists' detection performance with respect to vessel segments

International Nuclear Information System (INIS)

Das, Marco; Muehlenbruch, Georg; Helm, Anita; Guenther, Rolf W.; Wildberger, Joachim E.; Bakai, Annemarie; Salganicoff, Marcos; Liang, Jianming; Wolf, Matthias; Stanzel, Sven

2008-01-01

The purpose was to assess the sensitivity of a CAD software prototype for the detection of pulmonary embolism in MDCT chest examinations with regard to vessel level and to assess the influence on radiologists' detection performance. Forty-three patients with suspected PE were included in this retrospective study. MDCT chest examinations with a standard PE protocol were acquired at a 16-slice MDCT. All patient data were read by three radiologists (R1, R2, R3), and all thrombi were marked. A CAD prototype software was applied to all datasets, and each finding of the software was analyzed with regard to vessel level. The standard of reference was assessed in a consensus read. Sensitivity for the radiologists and CAD software was assessed. Thirty-three patients were positive for PE, with a total of 215 thrombi. The mean overall sensitivity for the CAD software alone was 83% (specificity, 80%). Radiologist sensitivity was 77% = R3, 82% = R2, and R1 = 87%. With the aid of the CAD software, sensitivities increased to 98% (R1), 93% (R2), and 92% (R3) (p<0.0001). CAD performance at the lobar level was 87%, at the segmental 90% and at the subsegmental 77%. With the use of CAD for PE, the detection performance of radiologists can be improved. (orig.)

Critical analysis of radiologist-patient interaction.

Science.gov (United States)

Morris, K J; Tarico, V S; Smith, W L; Altmaier, E M; Franken, E A

1987-05-01

A critical incident interview technique was used to identify features of radiologist-patient interactions considered effective and ineffective by patients. During structured interviews with 35 radiology patients and five patients' parents, three general categories of physician behavior were described: attention to patient comfort, explanation of procedure and results, and interpersonal sensitivity. The findings indicated that patients are sensitive to physicians' interpersonal styles and that they want physicians to explain procedures and results in an understandable manner and to monitor their well-being during procedures. The sample size of the study is small; thus further confirmation is needed. However, the implications for training residents and practicing radiologists in these behaviors are important in the current competitive medical milieu.

Medico-legal claims against English radiologists: 1995-2006.

Science.gov (United States)

Halpin, S F S

2009-12-01

A list of claims against radiologists from 1995-2006 was obtained from the NHS Litigation Authority. It shows a total of 440 claims. The largest number of claims (199) related to delayed or missed diagnoses of cancer, and 73 claims related to breast radiology. There is a trend for a mild increase in the number of claims each year. 30 claims were made after a false-positive diagnosis of cancer. Just under pound8.5 million has so far been paid in damages, with a further pound5 million in legal fees. A claim for multiple missed diagnoses of breast cancer led to a pay-out of pound464 000 ( pound673 000 after legal fees); the largest sum awarded following a delay in the diagnosis of an individual cancer was pound300 000. The subtle legal distinction between error and negligence is reviewed here. The reason why breast radiologists are more likely to be sued than any other type of British radiologist is also discussed, along with the implications for UK radiological practice, particularly in light of the recent Chief Medical Officer's report on revalidation. A method is proposed that may protect radiologists from allegations of clinical negligence in the future.

Improving the accuracy of dynamic mass calculation

Directory of Open Access Journals (Sweden)

Oleksandr F. Dashchenko

2015-06-01

Full Text Available With the acceleration of goods transporting, cargo accounting plays an important role in today's global and complex environment. Weight is the most reliable indicator of the materials control. Unlike many other variables that can be measured indirectly, the weight can be measured directly and accurately. Using strain-gauge transducers, weight value can be obtained within a few milliseconds; such values correspond to the momentary load, which acts on the sensor. Determination of the weight of moving transport is only possible by appropriate processing of the sensor signal. The aim of the research is to develop a methodology for weighing freight rolling stock, which increases the accuracy of the measurement of dynamic mass, in particular wagon that moves. Apart from time-series methods, preliminary filtration for improving the accuracy of calculation is used. The results of the simulation are presented.

Fractal Analysis of Radiologists Visual Scanning Pattern in Screening Mammography

Energy Technology Data Exchange (ETDEWEB)

Alamudun, Folami T [ORNL; Yoon, Hong-Jun [ORNL; Hudson, Kathy [University of Tennessee, Knoxville (UTK); Morin-Ducote, Garnetta [University of Tennessee, Knoxville (UTK); Tourassi, Georgia [ORNL

2015-01-01

Several investigators have investigated radiologists visual scanning patterns with respect to features such as total time examining a case, time to initially hit true lesions, number of hits, etc. The purpose of this study was to examine the complexity of the radiologists visual scanning pattern when viewing 4-view mammographic cases, as they typically do in clinical practice. Gaze data were collected from 10 readers (3 breast imaging experts and 7 radiology residents) while reviewing 100 screening mammograms (24 normal, 26 benign, 50 malignant). The radiologists scanpaths across the 4 mammographic views were mapped to a single 2-D image plane. Then, fractal analysis was applied on the derived scanpaths using the box counting method. For each case, the complexity of each radiologist s scanpath was estimated using fractal dimension. The association between gaze complexity, case pathology, case density, and radiologist experience was evaluated using 3 factor fixed effects ANOVA. ANOVA showed that case pathology, breast density, and experience level are all independent predictors of the visual scanning pattern complexity. Visual scanning patterns are significantly different for benign and malignant cases than for normal cases as well as when breast parenchyma density changes.

Error Estimation and Accuracy Improvements in Nodal Transport Methods

International Nuclear Information System (INIS)

Zamonsky, O.M.

2000-01-01

The accuracy of the solutions produced by the Discrete Ordinates neutron transport nodal methods is analyzed.The obtained new numerical methodologies increase the accuracy of the analyzed scheems and give a POSTERIORI error estimators. The accuracy improvement is obtained with new equations that make the numerical procedure free of truncation errors and proposing spatial reconstructions of the angular fluxes that are more accurate than those used until present. An a POSTERIORI error estimator is rigurously obtained for one dimensional systems that, in certain type of problems, allows to quantify the accuracy of the solutions. From comparisons with the one dimensional results, an a POSTERIORI error estimator is also obtained for multidimensional systems. LOCAL indicators, which quantify the spatial distribution of the errors, are obtained by the decomposition of the menctioned estimators. This makes the proposed methodology suitable to perform adaptive calculations. Some numerical examples are presented to validate the theoretical developements and to illustrate the ranges where the proposed approximations are valid

Prevalence of cancer risk factors among women radiologists and radiology assistants in Lithuania

International Nuclear Information System (INIS)

Samerdokiene, V.; Kurtinaitis, J.; Atkocius, V. and others

2005-01-01

The aim of the work was to study potential cancer risk factors among radiologists and non-radiologists in Lithuania. Cancer risk factors were investigated among female medical staff at the departments of ionizing (243, 33.33%) and non-ionizing environment (486, 66.67%). The questionnaire covered the diet, lifestyle, reproductive factors as well as the demographic and physical characteristics. Univariate analysis was done separately for physicians and nurses. Each of risk factors was evaluated in stratified analysis for unequal ORs using Mantel-Haenszel estimate control for age and occupation. Evaluation of features of risk factors among radiologists vs. non-radiologists has shown that smoking was most the prevalent risk factor among radiologists and radiology assistants. Despite the relatively low prevalence, the questionnaire data showed the higher frequency of smoking among radiologists (OR = 2.78, 95% CI 1.12-6.87) and radiology assistants (OR = 2.25, 95% 1.38-3.66) compared to non-radiologists. The prevalence of non-users and occasional users was 74% to 66%, respectively. Alcohol use by smoking among radiologists was influenced insignificantly. The cohort of radiologists in Lithuania offer an opportunity for obtaining direct observational evidence on health effects associated with chronic low-dose radiation exposure. The data on possible cancer risk factors can be helpful for validation of the risks in future. (author)

Nonresearch Industry Payments to Radiologists: Characteristics and Associations With Regional Medical Imaging Utilization.

Science.gov (United States)

Kokabi, Nima; Junn, Jacqueline C; Xing, Minzhi; Hemingway, Jennifer; Hughes, Danny R; Duszak, Richard

2017-03-01

To evaluate characteristics of nonresearch industry payments to radiologists and associations with regional diagnostic imaging utilization. Using 2014 CMS Open Payment data, all disclosed nonresearch-related industry payments to radiologists were identified. Health Resources and Services Administration Area Health Resources Files were used to identify actual and population-weighted numbers of radiologists by state. Utilizing the 5% random beneficiary sample CMS Research Identifiable Files from 2014, average Medicare imaging spending per beneficiary in each state was calculated. Average frequency and dollar amounts of nonresearch nonroyalty payments to radiologists were calculated at the state level. Using the Pearson correlation coefficient, the relationship between frequency and amounts of nonresearch payments to radiologists versus per-beneficiary Medicare imaging spending was evaluated at the state level. Overall, 2,008 radiologists (1,670 diagnostic, 338 interventional) received nonresearch nonroyalty payments from industry, representing 5.2% of all 38,857 radiologists nationwide. A total of 4,975 individual transfers translated to 2.5 ± 1.3 discrete payments per receiving radiologist with a mean of $432 ± $1,976 (median $26; range $1-$34,050). Food and beverage expenses constituted the vast majority of disclosed transfers (4,111; 83%), followed by travel and lodging (444; 9%), consulting fees (279; 6%), and educational expenses (51; 1%). Considerable geographic variation in payments was observed, ranging from 0% of radiologists in Vermont to 12.9% in the District of Columbia. No correlation was identified between average per-beneficiary Medicare imaging spending and the proportion of nonresearch-funded radiologists in each state (r = 0.06). Similarly, no correlation was identified between average per-beneficiary Medicare imaging spending and the average nonresearch transfer amount to radiologists in each state (r = -0.08). In 2014, only a small minority of

Accuracy Improvement Capability of Advanced Projectile Based on Course Correction Fuze Concept

OpenAIRE

Elsaadany, Ahmed; Wen-jun, Yi

2014-01-01

Improvement in terminal accuracy is an important objective for future artillery projectiles. Generally it is often associated with range extension. Various concepts and modifications are proposed to correct the range and drift of artillery projectile like course correction fuze. The course correction fuze concepts could provide an attractive and cost-effective solution for munitions accuracy improvement. In this paper, the trajectory correction has been obtained using two kinds of course corr...

Admission Privileges and Clinical Responsibilities for Interventional Radiologists

Energy Technology Data Exchange (ETDEWEB)

Al-Kutoubi, Aghiad, E-mail: mk00@aub.edu.lb [The American University of Beirut Medical Center, IR Division, The Department of Diagnostic Radiology (Lebanon)

2015-04-15

Although clinical involvement by interventional radiologists in the care of their patients was advocated at the inception of the specialty, the change into the clinical paradigm has been slow and patchy for reasons related to pattern of practice, financial remuneration or absence of training. The case for the value of clinical responsibilities has been made in a number of publications and the consequences of not doing so have been manifest in the erosion of the role of the interventional radiologists particularly in the fields of peripheral vascular and neuro intervention. With the recent recognition of interventional radiology (IR) as a primary specialty in the USA and the formation of IR division in the Union of European Medical Specialists and subsequent recognition of the subspecialty in many European countries, it is appropriate to relook at the issue and emphasize the need for measures to promote the clinical role of the interventional radiologist.

Admission Privileges and Clinical Responsibilities for Interventional Radiologists

International Nuclear Information System (INIS)

Al-Kutoubi, Aghiad

2015-01-01

Although clinical involvement by interventional radiologists in the care of their patients was advocated at the inception of the specialty, the change into the clinical paradigm has been slow and patchy for reasons related to pattern of practice, financial remuneration or absence of training. The case for the value of clinical responsibilities has been made in a number of publications and the consequences of not doing so have been manifest in the erosion of the role of the interventional radiologists particularly in the fields of peripheral vascular and neuro intervention. With the recent recognition of interventional radiology (IR) as a primary specialty in the USA and the formation of IR division in the Union of European Medical Specialists and subsequent recognition of the subspecialty in many European countries, it is appropriate to relook at the issue and emphasize the need for measures to promote the clinical role of the interventional radiologist

Combined MRI and MRS improves pre-therapeutic diagnoses of pediatric brain tumors over MRI alone

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Shiroishi, Mark S.; Nelson, Marvin D. [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Radiology, Los Angeles, CA (United States); Panigrahy, Ashok [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Radiology, Los Angeles, CA (United States); Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Department of Pediatric Radiology, Pittsburgh, PA (United States); Moore, Kevin R. [Primary Children' s Medical Center, Department of Radiology, Salt Lake City, UT (United States); Gilles, Floyd H. [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Pathology, Los Angeles, CA (United States); Gonzalez-Gomez, Ignacio [All Children' s Hospital, Department of Pathology, St. Petersburg, FL (United States); Blueml, Stefan [Children' s Hospital Los Angeles/Keck School of Medicine of USC, Department of Radiology, Los Angeles, CA (United States); Rudi Schulte Research Institute, Santa Barbara, CA (United States)

2015-09-15

The specific goal of this study was to determine whether the inclusion of MRS had a measureable and positive impact on the accuracy of pre-surgical MR examinations of untreated pediatric brain tumors over that of MRI alone in clinical practice. Final imaging reports of 120 pediatric patients with newly detected brain tumors who underwent combined MRI/MRS examinations were retrospectively reviewed. Final pathology was available in all cases. Group A comprised 60 subjects studied between June 2001 and January 2005, when MRS was considered exploratory and radiologists utilized only conventional MRI to arrive at a diagnosis. For group B, comprising 60 subjects studied between January 2005 and March 2008, the radiologists utilized information from both MRI and MRS. Furthermore, radiologists revisited group A (blind review, time lapse >4 years) to determine whether the additional information from MRS would have altered their interpretation. Sixty-three percent of patients in group A were diagnosed correctly, whereas in 10 % the report was partially correct with the final tumor type mentioned (but not mentioned as most likely tumor), while in 27 % of cases the reports were wrong. For group B, the diagnoses were correct in 87 %, partially correct in 5 %, and incorrect in 8 % of the cases, which is a significant improvement (p < 0.005). Re-review of combined MRI and MRS of group A resulted 87 % correct, 7 % partially correct, and 7 % incorrect diagnoses, which is a significant improvement over the original diagnoses (p < 0.05). Adding MRS to conventional MRI significantly improved diagnostic accuracy in preoperative pediatric patients with untreated brain tumors. (orig.)

Combined MRI and MRS improves pre-therapeutic diagnoses of pediatric brain tumors over MRI alone

International Nuclear Information System (INIS)

Shiroishi, Mark S.; Nelson, Marvin D.; Panigrahy, Ashok; Moore, Kevin R.; Gilles, Floyd H.; Gonzalez-Gomez, Ignacio; Blueml, Stefan

2015-01-01

The specific goal of this study was to determine whether the inclusion of MRS had a measureable and positive impact on the accuracy of pre-surgical MR examinations of untreated pediatric brain tumors over that of MRI alone in clinical practice. Final imaging reports of 120 pediatric patients with newly detected brain tumors who underwent combined MRI/MRS examinations were retrospectively reviewed. Final pathology was available in all cases. Group A comprised 60 subjects studied between June 2001 and January 2005, when MRS was considered exploratory and radiologists utilized only conventional MRI to arrive at a diagnosis. For group B, comprising 60 subjects studied between January 2005 and March 2008, the radiologists utilized information from both MRI and MRS. Furthermore, radiologists revisited group A (blind review, time lapse >4 years) to determine whether the additional information from MRS would have altered their interpretation. Sixty-three percent of patients in group A were diagnosed correctly, whereas in 10 % the report was partially correct with the final tumor type mentioned (but not mentioned as most likely tumor), while in 27 % of cases the reports were wrong. For group B, the diagnoses were correct in 87 %, partially correct in 5 %, and incorrect in 8 % of the cases, which is a significant improvement (p < 0.005). Re-review of combined MRI and MRS of group A resulted 87 % correct, 7 % partially correct, and 7 % incorrect diagnoses, which is a significant improvement over the original diagnoses (p < 0.05). Adding MRS to conventional MRI significantly improved diagnostic accuracy in preoperative pediatric patients with untreated brain tumors. (orig.)

Sex Differences in Radiologist Salary in U.S. Public Medical Schools.

Science.gov (United States)

Kapoor, Neena; Blumenthal, Daniel M; Smith, Stacy E; Ip, Ivan K; Khorasani, Ramin

2017-11-01

The purpose of this study was to evaluate salary differences between male and female academic radiologists at U.S. medical schools. Laws in several U.S. states mandate public release of government records, including salary information of state employees. From online salary data published by 12 states, we extracted the salaries of all academic radiologists at 24 public medical schools during 2011-2013 (n = 573 radiologists). In this institutional review board-approved cross-sectional study, we linked these data to a physician database with information on physician sex, age, faculty rank, years since residency, clinical trial involvement, National Institutes of Health (NIH) funding, scientific publications, and clinical volume measured by 2013 Medicare payments. Sex difference in salary, the primary outcome, was estimated using a multilevel logistic regression adjusting for these factors. Among 573 academic radiologists, 171 (29.8%) were women. Female radiologists were younger (48.5 vs 51.6 years, p = 0.001) and more likely to be assistant professors (50.9% [87/171] vs 40.8% [164/402], p = 0.026). Salaries between men and women were similar in unadjusted analyses ($290,660 vs $289,797; absolute difference, $863; 95% CI, -$18,363 to $20,090), and remained so after adjusting for age, faculty rank, years since residency, clinical trial involvement, publications, total Medicare payments, NIH funding, and graduation from a highly ranked medical school. Among academic radiologists employed at 24 U.S. public medical schools, male and female radiologists had similar annual salaries both before and after adjusting for several variables known to influence salary among academic physicians.

Breast Density Legislation in New England: A Survey Study of Practicing Radiologists.

Science.gov (United States)

Lourenco, Ana P; DiFlorio-Alexander, Roberta M; Slanetz, Priscilla J

2017-10-01

This study aimed to assess radiologists' knowledge about breast density legislation as well as perceived practice changes resulting from the enactment of breast density legislation. This is an institutional review board-exempt anonymous email survey of 523 members of the New England Roentgen Ray Society. In addition to radiologist demographics, survey questions addressed radiologist knowledge of breast density legislation, knowledge of breast density as a risk factor for breast cancer, recommendations for supplemental screening, and perceived practice changes resulting from density notification legislation. Of the 523 members, 96 responded, yielding an 18% response rate. Seventy-three percent of respondents practiced in a state with breast density legislation. Sixty-nine percent felt that breast density notification increased patient anxiety about breast cancer, but also increased patient (74%) and provider (66%) understanding of the effect of breast density on mammographic sensitivity. Radiologist knowledge of the relative risk of breast cancer when comparing breasts of different density was variable. Considerable confusion and controversy regarding breast density persists, even among practicing radiologists. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Radiologists' Usage of Social Media: Results of the RANSOM Survey.

Science.gov (United States)

Ranschaert, Erik R; Van Ooijen, Peter M A; McGinty, Geraldine B; Parizel, Paul M

2016-08-01

The growing use of social media is transforming the way health care professionals (HCPs) are communicating. In this changing environment, it could be useful to outline the usage of social media by radiologists in all its facets and on an international level. The main objective of the RANSOM survey was to investigate how radiologists are using social media and what is their attitude towards them. The second goal was to discern differences in tendencies among American and European radiologists. An international survey was launched on SurveyMonkey ( https://www.surveymonkey.com ) asking questions about the platforms they prefer, about the advantages, disadvantages, and risks, and about the main incentives and barriers to use social media. A total of 477 radiologists participated in the survey, of which 277 from Europe and 127 from North America. The results show that 85 % of all survey participants are using social media, mostly for a mixture of private and professional reasons. Facebook is the most popular platform for general purposes, whereas LinkedIn and Twitter are more popular for professional usage. The most important reason for not using social media is an unwillingness to mix private and professional matters. Eighty-two percent of all participants are aware of the educational opportunities offered by social media. The survey results underline the need to increase radiologists' skills in using social media efficiently and safely. There is also a need to create clear guidelines regarding the online and social media presence of radiologists to maximize the potential benefits of engaging with social media.

Burnout of Radiologists: Frequency, Risk Factors, and Remedies: A Report of the ACR Commission on Human Resources.

Science.gov (United States)

Harolds, Jay A; Parikh, Jay R; Bluth, Edward I; Dutton, Sharon C; Recht, Michael P

2016-04-01

Burnout is a concern for radiologists. The burnout rate is greater among diagnostic radiologists than the mean for all physicians, while radiation oncologists have a slightly lower burnout rate. Burnout can result in unprofessional behavior, thoughts of suicide, premature retirement, and errors in patient care. Strategies to reduce burnout include addressing the sources of job dissatisfaction, instilling lifestyle balance, finding reasons to work other than money, improving money management, developing a support group, and seeking help when needed. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

The opinion and experiences of Dutch orthopedic surgeons and radiologists about diagnostic musculoskeletal ultrasound imaging in primary care: a survey.

Science.gov (United States)

Scholten-Peeters, Gwendolijne G M; Franken, Nicole; Beumer, Annechien; Verhagen, Arianne P

2014-04-01

The use of diagnostic musculoskeletal ultrasound (DMUS) in primary health care has increased in the recent years. Nevertheless, there are hardly any data concerning the reliability, accuracy and treatment consequences of DMUS used by physical therapists or general practitioners. Moreover, there are no papers published about how orthopedic surgeons or radiologists deal with the results of DMUS performed in primary care. Therefore, our aim is to evaluate the opinion, possible advantages or disadvantages and experiences of Dutch orthopedic surgeons and radiologists about DMUS in primary care. A cross-sectional survey in which respondents completed a self-developed questionnaire to determine their opinion, experiences, advantages, disadvantages of performing DMUS in primary care. Questionnaires were sent to 838 Dutch orthopedic surgeons and radiologists of which 213 were returned (response rate 25.4%). Our respondents saw no additional value for health care for diagnostic DMUS in primary care. DMUSs were generally repeated in secondary care. They perceived more disadvantages than advantages of performing DMUS in primary care. Mentioned disadvantages were: 'false positive results' (71.4%), 'lack of experience' (70%), 'insufficient education' (69.5%), not able to relate the outcomes of DMUS with other forms of diagnostic imaging' (65.7%), and 'false negative results' (65.3%). Radiologists and orthopedic surgeons sampled in the Netherlands show low trust in DMUS knowledge of physical therapists and general practitioners. The results should be interpreted with caution because of the small response rate and the lack of representativeness to other countries. Published by Elsevier Ltd.

Feasibility of using a biowatch to monitor GSR as a measure of radiologists' stress and fatigue

Science.gov (United States)

Krupinski, Elizabeth A.; MacKinnon, Lea; Reiner, Bruce I.

2015-03-01

We have been investigating the impact of fatigue on diagnostic performance of radiologists interpreting medical images. In previous studies we found evidence that eye strain could be objectively measured and that it correlates highly with degradations in diagnostic accuracy as radiologists work long hours. Eye strain however can be difficult to measure in a non-invasive and continuous manner over the work day so we have been investigating other ways to measure physiological stress and fatigue. In this study we evaluated the feasibility of using a commercially available biowatch to measure galvanic skin response (GSR), a well known indicator of stress. 10 radiology residents wore the biowatch for about 8 hours during their normal work day and data were automatically collected at 10 Hz. They completed the Swedish Occupational Fatigue Inventory (SOFI) at the start and finish of the day. GSR values (microsiemens) ranged from 0.14 to 38.27 with an average of 0.50 (0.28 median). Overall GSR tended to be fairly constant as the day progressed, but there were definite spikes indicating higher levels of stress. SOFI scores indicated greater levels of fatigue and stress at the end of the work day. Although further work is needed, GSR measurements obtained via an easy to wear watch may provide a means to monitor stress/fatigue and alert radiologists when to take a break from interpreting images to avoid making errors.

Improving supervised classification accuracy using non-rigid multimodal image registration: detecting prostate cancer

Science.gov (United States)

Chappelow, Jonathan; Viswanath, Satish; Monaco, James; Rosen, Mark; Tomaszewski, John; Feldman, Michael; Madabhushi, Anant

2008-03-01

Computer-aided diagnosis (CAD) systems for the detection of cancer in medical images require precise labeling of training data. For magnetic resonance (MR) imaging (MRI) of the prostate, training labels define the spatial extent of prostate cancer (CaP); the most common source for these labels is expert segmentations. When ancillary data such as whole mount histology (WMH) sections, which provide the gold standard for cancer ground truth, are available, the manual labeling of CaP can be improved by referencing WMH. However, manual segmentation is error prone, time consuming and not reproducible. Therefore, we present the use of multimodal image registration to automatically and accurately transcribe CaP from histology onto MRI following alignment of the two modalities, in order to improve the quality of training data and hence classifier performance. We quantitatively demonstrate the superiority of this registration-based methodology by comparing its results to the manual CaP annotation of expert radiologists. Five supervised CAD classifiers were trained using the labels for CaP extent on MRI obtained by the expert and 4 different registration techniques. Two of the registration methods were affi;ne schemes; one based on maximization of mutual information (MI) and the other method that we previously developed, Combined Feature Ensemble Mutual Information (COFEMI), which incorporates high-order statistical features for robust multimodal registration. Two non-rigid schemes were obtained by succeeding the two affine registration methods with an elastic deformation step using thin-plate splines (TPS). In the absence of definitive ground truth for CaP extent on MRI, classifier accuracy was evaluated against 7 ground truth surrogates obtained by different combinations of the expert and registration segmentations. For 26 multimodal MRI-WMH image pairs, all four registration methods produced a higher area under the receiver operating characteristic curve compared to that

Occupational radiation risk to radiologists

International Nuclear Information System (INIS)

Schuettmann, W.

1981-01-01

A review is given of the most important publications dealing with attempts to estimate the occupational radiation risk to radiologists by comparing data on their mortality from leukemia and other forms of cancer with respective data for other physicians who were not occupationally exposed to ionizing radiation. (author)

IMPROVED MOTOR-TIMING: EFFECTS OF SYNCHRONIZED METRO-NOME TRAINING ON GOLF SHOT ACCURACY

Directory of Open Access Journals (Sweden)

Louise Rönnqvist

2009-12-01

Full Text Available This study investigates the effect of synchronized metronome training (SMT on motor timing and how this training might affect golf shot accuracy. Twenty-six experienced male golfers participated (mean age 27 years; mean golf handicap 12.6 in this study. Pre- and post-test investigations of golf shots made by three different clubs were conducted by use of a golf simulator. The golfers were randomized into two groups: a SMT group and a Control group. After the pre-test, the golfers in the SMT group completed a 4-week SMT program designed to improve their motor timing, the golfers in the Control group were merely training their golf-swings during the same time period. No differences between the two groups were found from the pre-test outcomes, either for motor timing scores or for golf shot accuracy. However, the post-test results after the 4-weeks SMT showed evident motor timing improvements. Additionally, significant improvements for golf shot accuracy were found for the SMT group and with less variability in their performance. No such improvements were found for the golfers in the Control group. As with previous studies that used a SMT program, this study's results provide further evidence that motor timing can be improved by SMT and that such timing improvement also improves golf accuracy

Improvement of Gaofen-3 Absolute Positioning Accuracy Based on Cross-Calibration

Directory of Open Access Journals (Sweden)

Mingjun Deng

2017-12-01

Full Text Available The Chinese Gaofen-3 (GF-3 mission was launched in August 2016, equipped with a full polarimetric synthetic aperture radar (SAR sensor in the C-band, with a resolution of up to 1 m. The absolute positioning accuracy of GF-3 is of great importance, and in-orbit geometric calibration is a key technology for improving absolute positioning accuracy. Conventional geometric calibration is used to accurately calibrate the geometric calibration parameters of the image (internal delay and azimuth shifts using high-precision ground control data, which are highly dependent on the control data of the calibration field, but it remains costly and labor-intensive to monitor changes in GF-3’s geometric calibration parameters. Based on the positioning consistency constraint of the conjugate points, this study presents a geometric cross-calibration method for the rapid and accurate calibration of GF-3. The proposed method can accurately calibrate geometric calibration parameters without using corner reflectors and high-precision digital elevation models, thus improving absolute positioning accuracy of the GF-3 image. GF-3 images from multiple regions were collected to verify the absolute positioning accuracy after cross-calibration. The results show that this method can achieve a calibration accuracy as high as that achieved by the conventional field calibration method.

Improved mammographic interpretation of masses using computer-aided diagnosis

Energy Technology Data Exchange (ETDEWEB)

Leichter, I. [Dept. of Electro-Optics, Jerusalem College of Technology (Israel); Fields, S.; Novak, B. [Dept. of Radiology, Hadassah University Hospital, Mt. Scopus Jerusalem (Israel); Nirel, R. [Dept. of Statistics, Hebrew University of Jerusalem, Mt. Scopus, Jerusalem (Israel); Bamberger, P. [Dept. of Electronics, Jerusalem College of Technology, Jerusalem (Israel); Lederman, R. [Department of Radiology, Hadassah University Hospital, Ein Kerem, Jerusalem (Israel); Buchbinder, S. [Department of Radiology, Montefiore Medical Center, University Hospital for the Albert Einstein College of Medicine, Bronx, New York (United States)

2000-02-01

The aim of this study was to evaluate the effectiveness of computerized image enhancement, to investigate criteria for discriminating benign from malignant mammographic findings by computer-aided diagnosis (CAD), and to test the role of quantitative analysis in improving the accuracy of interpretation of mass lesions. Forty sequential mammographically detected mass lesions referred for biopsy were digitized at high resolution for computerized evaluation. A prototype CAD system which included image enhancement algorithms was used for a better visualization of the lesions. Quantitative features which characterize the spiculation were automatically extracted by the CAD system for a user-defined region of interest (ROI). Reference ranges for malignant and benign cases were acquired from data generated by 214 known retrospective cases. The extracted parameters together with the reference ranges were presented to the radiologist for the analysis of 40 prospective cases. A pattern recognition scheme based on discriminant analysis was trained on the 214 retrospective cases, and applied to the prospective cases. Accuracy of interpretation with and without the CAD system, as well as the performance of the pattern recognition scheme, were analyzed using receiver operating characteristics (ROC) curves. A significant difference (p < 0.005) was found between features extracted by the CAD system for benign and malignant cases. Specificity of the CAD-assisted diagnosis improved significantly (p < 0.02) from 14 % for the conventional assessment to 50 %, and the positive predictive value increased from 0.47 to 0.62 (p < 0.04). The area under the ROC curve (A{sub z}) increased significantly (p < 0.001) from 0.66 for the conventional assessment to 0.81 for the CAD-assisted analysis. The A{sub z} for the results of the pattern recognition scheme was higher (0.95). The results indicate that there is an improved accuracy of diagnosis with the use of the mammographic CAD system above that

Unilateral Hemithorax Opacification on Chest Radiograph : Comparison of Diagnostic Accuracy of Chest Ultrasonography with CT

Energy Technology Data Exchange (ETDEWEB)

Namkung, Sook; Lee, Kyung Soo; Kwon, O Jung [Samsung Medical Center, Seoul (Korea, Republic of); Chung, Seung Eun [Sangkye Paek Hospital, Seoul (Korea, Republic of)

1996-12-15

To compare the diagnostic accuracy of chest ultrasonography (US) with computed tomography (CT) inpatients with opacification more than one third of unilateral hemithorax on chest radiograph (CXR). Chest US and CT scans from 41 consecutive patients with opacification more than one third of unilateral hemithorax on CXR were prospectively evaluated by two independent radiologists. Each radiologist recorded 1) the nature of pleural effusion (transudate vs. exudate), 2) presence or absence of pulmonary lesion, 3) the characteristic of pulmonary lesion (consolidation or atelectasis and tumor), and 4) presence of solid pleural tumor. The diagnostic accuracy of chest US was compared with CT scan in patients with pleural, pulmonary or other disease. In 32 patients with pleural effusion, differentiation between transudate and exudate was feasible in 27 (84%) patients with US and 26 (81%) patients with CT. In 32 patients with pulmonary and other pleural diseases, sensitivity, specificity and accuracy of US in lesion detection were 86%, 75% and 83% respectively when CT was regarded as a diagnostic gold standard. The diagnostic accuracy of chest US is comparable to CT in patients with hemithorax opacification on CXR

Unilateral Hemithorax Opacification on Chest Radiograph : Comparison of Diagnostic Accuracy of Chest Ultrasonography with CT

International Nuclear Information System (INIS)

Namkung, Sook; Lee, Kyung Soo; Kwon, O Jung; Chung, Seung Eun

1996-01-01

To compare the diagnostic accuracy of chest ultrasonography (US) with computed tomography (CT) inpatients with opacification more than one third of unilateral hemithorax on chest radiograph (CXR). Chest US and CT scans from 41 consecutive patients with opacification more than one third of unilateral hemithorax on CXR were prospectively evaluated by two independent radiologists. Each radiologist recorded 1) the nature of pleural effusion (transudate vs. exudate), 2) presence or absence of pulmonary lesion, 3) the characteristic of pulmonary lesion (consolidation or atelectasis and tumor), and 4) presence of solid pleural tumor. The diagnostic accuracy of chest US was compared with CT scan in patients with pleural, pulmonary or other disease. In 32 patients with pleural effusion, differentiation between transudate and exudate was feasible in 27 (84%) patients with US and 26 (81%) patients with CT. In 32 patients with pulmonary and other pleural diseases, sensitivity, specificity and accuracy of US in lesion detection were 86%, 75% and 83% respectively when CT was regarded as a diagnostic gold standard. The diagnostic accuracy of chest US is comparable to CT in patients with hemithorax opacification on CXR

Lung nodule detection in pediatric chest CT: quantitative relationship between image quality and radiologist performance.

Science.gov (United States)

Li, Xiang; Samei, Ehsan; Barnhart, Huiman X; Gaca, Ana Maria; Hollingsworth, Caroline L; Maxfield, Charles M; Carrico, Caroline W T; Colsher, James G; Frush, Donald P

2011-05-01

To determine the quantitative relationship between image quality and radiologist performance in detecting small lung nodules in pediatric CT. The study included clinical chest CT images of 30 pediatric patients (0-16 years) scanned at tube currents of 55-180 mA. Calibrated noise addition software was used to simulate cases at three nominal mA settings: 70, 35, and 17.5 mA, resulting in quantum noise of 7-32 Hounsfield Unit (HU). Using a validated nodule simulation technique, lung nodules with diameters of 3-5 mm and peak contrasts of 200-500 HU were inserted into the cases, which were then randomized and rated independently by four experienced pediatric radiologists for nodule presence on a continuous scale from 0 (definitely absent) to 100 (definitely present). The receiver operating characteristic (ROC) data were analyzed to quantify the relationship between diagnostic accuracy (area under the ROC curve, AUC) and image quality (the product of nodule peak contrast and displayed diameter to noise ratio, CDNR display). AUC increased rapidly from 0.70 to 0.87 when CDNR display increased from 60 to 130 mm, followed by a slow increase to 0.94 when CDNR display further increased to 257 mm. For the average nodule diameter (4 mm) and contrast (350 HU), AUC decreased from 0.93 to 0.71 with noise increased from 7 to 28 HU. We quantified the relationship between image quality and the performance of radiologists in detecting lung nodules in pediatric CT. The relationship can guide CT protocol design to achieve the desired diagnostic performance at the lowest radiation dose.

Exploring the Usability of Mobile Apps Supporting Radiologists' Training in Diagnostic Decision Making.

Science.gov (United States)

Kim, Min Soon; Aro, Michael R; Lage, Kraig J; Ingalls, Kevin L; Sindhwani, Vivek; Markey, Mia K

2016-03-01

The objective of this study was to conduct a usability evaluation of mobile apps for supporting education and training in radiologic diagnostic decision-making processes. Of 381 mobile apps available at two major stores (Google Play and iTunes), eight iOS apps were selected for laboratory-based usability tests. Six staff radiologists completed eight app-specific task sets, using a think-aloud strategy. The triangular methods approach included quantitative performance measures, System Usability Scale (SUS), and qualitative thematic analysis using heuristic usability principles of usability issues. Overall, radiologists achieved higher than 70% success, with favorable SUS scores, in completing the tasks for seven of the eight apps. However, task success rate and SUS score had a weak relation (r = 0.23), indicating that the perceived usability may not reflect the holistic usability of the app. Task analysis and self-report revealed 108 usability issues, which were condensed to 55 unique issues and categorized by nine usability themes and mapped to ten usability heuristics. Nonintuitive functionality (eg, nonintuitive or misleading labels) was the most frequent theme observed, leading to inefficient navigation. These usability findings were consistent with the 13 improvements the radiologists suggested. This study demonstrates the feasibility of usability evaluation of radiology mobile apps and suggests potential improvements in the development of radiology mobile apps. This study also suggests that proficiency with mobile devices may not be equivalent to being an expert user, proficient in using the apps. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Work-Related Injuries of Radiologists and Possible Ergonomic Solutions: Recommendations From the ACR Commission on Human Resources.

Science.gov (United States)

Sze, Gordon; Bluth, Edward I; Bender, Claire E; Parikh, Jay R

2017-10-01

Increasingly, radiologists' workplaces revolve around PACS and digital imaging. Use of these technologies can lead to repetitive strain injuries, many of which can be exacerbated by specific features of a radiology practice environment. Ergonomic approaches, such as proper reading room structure, lighting, temperature, noise, and equipment setup, can help decrease the frequency and severity of repetitive strain injuries and improve radiologist productivity. However, ergonomic approaches are complex, include all aspects of the radiology practice environment, and are best implemented along with proper training of the practicing radiologists. The ergonomic approaches considered most important by members of the ACR Commission on Human Resources are presented in this report, and this information may serve as an aid in departmental planning. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

1000-Case Reader Study of Radiologists' Performance in Interpretation of Automated Breast Volume Scanner Images with a Computer-Aided Detection System.

Science.gov (United States)

Xu, Xiaojing; Bao, Lingyun; Tan, Yanjuan; Zhu, Luoxi; Kong, Fanlei; Wang, Wei

2018-05-28

cases without CADe and their group 2 cases with CADe. The areas under the receiver operating characteristic curves of all readers were 0.784 for reading with CADe and 0.747 without CADe. Areas under the curves with and without CADe were 0.833 and 0.829 for group A, 0.757 and 0.696 for group B and 0.759 and 0.718 for group C. All differences in areas under the curve were statistically significant (p <0.05), except that for group A. The average reading time was 9.3% (p < < 0.05) faster with CADe for all readers. In summary, CADe improves radiologist performance with respect to both accuracy and reading time for the detection of breast cancer using the ABVS, with the greater benefit for those inexperienced with ABVS. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

Dynamic contrast-enhanced MRI improves accuracy for detecting focal splenic involvement in children and adolescents with Hodgkin disease

International Nuclear Information System (INIS)

Punwani, Shonit; Taylor, Stuart A.; Halligan, Steve; Cheung, King Kenneth; Skipper, Nicholas; Bell, Nichola; Humphries, Paul D.; Bainbridge, Alan; Groves, Ashley M.; Hain, Sharon F.; Ben-Haim, Simona; Shankar, Ananth; Daw, Stephen

2013-01-01

Accurate assessment of splenic disease is important for staging Hodgkin lymphoma. The purpose of this study was to assess T2-weighted imaging with and without dynamic contrast-enhanced (DCE) MRI for evaluation of splenic Hodgkin disease. Thirty-one children with Hodgkin lymphoma underwent whole-body T2-weighted MRI with supplementary DCE splenic imaging, and whole-body PET-CT before and following chemotherapy. Two experienced nuclear medicine physicians derived a PET-CT reference standard for splenic disease, augmented by follow-up imaging. Unaware of the PET-CT, two experienced radiologists independently evaluated MRI exercising a locked sequential read paradigm (T2-weighted then DCE review) and recorded the presence/absence of splenic disease at each stage. Performance of each radiologist was determined prior to and following review of DCE-MRI. Incorrect MRI findings were ascribed to reader (lesion present on MRI but missed by reader) or technical (lesion not present on MRI) error. Seven children had splenic disease. Sensitivity/specificity of both radiologists for the detection of splenic involvement using T2-weighted images alone was 57%/100% and increased to 100%/100% with DCE-MRI. There were three instances of technical error on T2-weighted imaging; all lesions were visible on DCE-MRI. T2-weighted imaging when complemented by DCE-MRI imaging may improve evaluation of Hodgkin disease splenic involvement. (orig.)

Dynamic contrast-enhanced MRI improves accuracy for detecting focal splenic involvement in children and adolescents with Hodgkin disease

Energy Technology Data Exchange (ETDEWEB)

Punwani, Shonit; Taylor, Stuart A.; Halligan, Steve [University College London, Centre for Medical Imaging, London (United Kingdom); University College London Hospital, Department of Radiology, London (United Kingdom); Cheung, King Kenneth; Skipper, Nicholas [University College London, Centre for Medical Imaging, London (United Kingdom); Bell, Nichola; Humphries, Paul D. [University College London Hospital, Department of Radiology, London (United Kingdom); Bainbridge, Alan [University College London, Department of Medical Physics and Bioengineering, London (United Kingdom); Groves, Ashley M.; Hain, Sharon F.; Ben-Haim, Simona [University College Hospital, Institute of Nuclear Medicine, London (United Kingdom); Shankar, Ananth; Daw, Stephen [University College London Hospital, Department of Paediatrics, London (United Kingdom)

2013-08-15

Accurate assessment of splenic disease is important for staging Hodgkin lymphoma. The purpose of this study was to assess T2-weighted imaging with and without dynamic contrast-enhanced (DCE) MRI for evaluation of splenic Hodgkin disease. Thirty-one children with Hodgkin lymphoma underwent whole-body T2-weighted MRI with supplementary DCE splenic imaging, and whole-body PET-CT before and following chemotherapy. Two experienced nuclear medicine physicians derived a PET-CT reference standard for splenic disease, augmented by follow-up imaging. Unaware of the PET-CT, two experienced radiologists independently evaluated MRI exercising a locked sequential read paradigm (T2-weighted then DCE review) and recorded the presence/absence of splenic disease at each stage. Performance of each radiologist was determined prior to and following review of DCE-MRI. Incorrect MRI findings were ascribed to reader (lesion present on MRI but missed by reader) or technical (lesion not present on MRI) error. Seven children had splenic disease. Sensitivity/specificity of both radiologists for the detection of splenic involvement using T2-weighted images alone was 57%/100% and increased to 100%/100% with DCE-MRI. There were three instances of technical error on T2-weighted imaging; all lesions were visible on DCE-MRI. T2-weighted imaging when complemented by DCE-MRI imaging may improve evaluation of Hodgkin disease splenic involvement. (orig.)

The impact of trained radiographers as concurrent readers on performance and reading time of experienced radiologists in the UK Lung Cancer Screening (UKLS) trial

International Nuclear Information System (INIS)

Nair, Arjun; Screaton, Nicholas J.; Clements, Leigh; Holemans, John A.; Jones, Diane; Barton, Bruce; Gartland, Natalie; Hansell, David M.; Devaraj, Anand; Duffy, Stephen W.; Baldwin, David R.; Field, John K.

2018-01-01

To compare radiologists' performance reading CTs independently with their performance using radiographers as concurrent readers in lung cancer screening. 369 consecutive baseline CTs performed for the UK Lung Cancer Screening (UKLS) trial were double-read by radiologists reading either independently or concurrently with a radiographer. In concurrent reading, the radiologist reviewed radiographer-identified nodules and then detected any additional nodules. Radiologists recorded their independent and concurrent reading times. For each radiologist, sensitivity, average false-positive detections (FPs) per case and mean reading times for each method were calculated. 694 nodules in 246/369 (66.7%) studies comprised the reference standard. Radiologists' mean sensitivity and average FPs per case both increased with concurrent reading compared to independent reading (90.8 ± 5.6% vs. 77.5 ± 11.2%, and 0.60 ± 0.53 vs. 0.33 ± 0.20, respectively; p < 0.05 for 3/4 and 2/4 radiologists, respectively). The mean reading times per case decreased from 9.1 ± 2.3 min with independent reading to 7.2 ± 1.0 min with concurrent reading, decreasing significantly for 3/4 radiologists (p < 0.05). The majority of radiologists demonstrated improved sensitivity, a small increase in FP detections and a statistically significantly reduced reading time using radiographers as concurrent readers. (orig.)

The impact of trained radiographers as concurrent readers on performance and reading time of experienced radiologists in the UK Lung Cancer Screening (UKLS) trial

Energy Technology Data Exchange (ETDEWEB)

Nair, Arjun [Guy' s and St Thomas' NHS Foundation Trust, Department of Radiology, London (United Kingdom); Screaton, Nicholas J.; Clements, Leigh [Papworth Hospital NHS Foundation Trust, Department of Radiology, Cambridge (United Kingdom); Holemans, John A.; Jones, Diane [Liverpool Heart and Chest Hospital, Department of Radiology, Liverpool, Merseyside (United Kingdom); Barton, Bruce; Gartland, Natalie; Hansell, David M.; Devaraj, Anand [Royal Brompton Hospital, Department of Radiology, London (United Kingdom); Duffy, Stephen W. [Barts and The London School of Medicine and Dentistry, Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, London (United Kingdom); Baldwin, David R. [Nottingham University Hospitals, Respiratory Medicine Unit, David Evans Research Centre, Nottingham (United Kingdom); Field, John K. [The University of Liverpool, Roy Castle Lung Cancer Research Programme, Department of Molecular and Clinical Cancer Medicine, Institute of Translational Medicine, Liverpool (United Kingdom)

2018-01-15

To compare radiologists' performance reading CTs independently with their performance using radiographers as concurrent readers in lung cancer screening. 369 consecutive baseline CTs performed for the UK Lung Cancer Screening (UKLS) trial were double-read by radiologists reading either independently or concurrently with a radiographer. In concurrent reading, the radiologist reviewed radiographer-identified nodules and then detected any additional nodules. Radiologists recorded their independent and concurrent reading times. For each radiologist, sensitivity, average false-positive detections (FPs) per case and mean reading times for each method were calculated. 694 nodules in 246/369 (66.7%) studies comprised the reference standard. Radiologists' mean sensitivity and average FPs per case both increased with concurrent reading compared to independent reading (90.8 ± 5.6% vs. 77.5 ± 11.2%, and 0.60 ± 0.53 vs. 0.33 ± 0.20, respectively; p < 0.05 for 3/4 and 2/4 radiologists, respectively). The mean reading times per case decreased from 9.1 ± 2.3 min with independent reading to 7.2 ± 1.0 min with concurrent reading, decreasing significantly for 3/4 radiologists (p < 0.05). The majority of radiologists demonstrated improved sensitivity, a small increase in FP detections and a statistically significantly reduced reading time using radiographers as concurrent readers. (orig.)

Accuracy Improvement of Boron Meter Adopting New Fitting Function and Multi-Detector

Directory of Open Access Journals (Sweden)

Chidong Kong

2016-12-01

Full Text Available This paper introduces a boron meter with improved accuracy compared with other commercially available boron meters. Its design includes a new fitting function and a multi-detector. In pressurized water reactors (PWRs in Korea, many boron meters have been used to continuously monitor boron concentration in reactor coolant. However, it is difficult to use the boron meters in practice because the measurement uncertainty is high. For this reason, there has been a strong demand for improvement in their accuracy. In this work, a boron meter evaluation model was developed, and two approaches were considered to improve the boron meter accuracy: the first approach uses a new fitting function and the second approach uses a multi-detector. With the new fitting function, the boron concentration error was decreased from 3.30 ppm to 0.73 ppm. With the multi-detector, the count signals were contaminated with noise such as field measurement data, and analyses were repeated 1,000 times to obtain average and standard deviations of the boron concentration errors. Finally, using the new fitting formulation and multi-detector together, the average error was decreased from 5.95 ppm to 1.83 ppm and its standard deviation was decreased from 0.64 ppm to 0.26 ppm. This result represents a great improvement of the boron meter accuracy.

Accuracy improvement of boron meter adopting new fitting function and multi-detector

Energy Technology Data Exchange (ETDEWEB)

Kong, Chidong; Lee, Hyun Suk; Tak, Tae Woo; Lee, Deok Jung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of); KIm, Si Hwan; Lyou, Seok Jean [Users Incorporated Company, Hansin S-MECA, Daejeon (Korea, Republic of)

2016-12-15

This paper introduces a boron meter with improved accuracy compared with other commercially available boron meters. Its design includes a new fitting function and a multi-detector. In pressurized water reactors (PWRs) in Korea, many boron meters have been used to continuously monitor boron concentration in reactor coolant. However, it is difficult to use the boron meters in practice because the measurement uncertainty is high. For this reason, there has been a strong demand for improvement in their accuracy. In this work, a boron meter evaluation model was developed, and two approaches were considered to improve the boron meter accuracy: the first approach uses a new fitting function and the second approach uses a multi-detector. With the new fitting function, the boron concentration error was decreased from 3.30 ppm to 0.73 ppm. With the multi-detector, the count signals were contaminated with noise such as field measurement data, and analyses were repeated 1,000 times to obtain average and standard deviations of the boron concentration errors. Finally, using the new fitting formulation and multi-detector together, the average error was decreased from 5.95 ppm to 1.83 ppm and its standard deviation was decreased from 0.64 ppm to 0.26 ppm. This result represents a great improvement of the boron meter accuracy.

A model to improve the accuracy of US Poison Center data collection.

Science.gov (United States)

Krenzelok, E P; Reynolds, K M; Dart, R C; Green, J L

2014-01-01

Over 2 million human exposure calls are reported annually to United States regional poison information centers. All exposures are documented electronically and submitted to the American Association of Poison Control Center's National Poison Data System. This database represents the largest data source available on the epidemiology of pharmaceutical and non-pharmaceutical poisoning exposures. The accuracy of these data is critical; however, research has demonstrated that inconsistencies and inaccuracies exist. This study outlines the methods and results of a training program that was developed and implemented to enhance the quality of data collection using acetaminophen exposures as a model. Eleven poison centers were assigned randomly to receive either passive or interactive education to improve medical record documentation. A task force provided recommendations on educational and training strategies and the development of a quality-measurement scorecard to serve as a data collection tool to assess poison center data quality. Poison centers were recruited to participate in the study. Clinical researchers scored the documentation of each exposure record for accuracy. Results. Two thousand two hundred cases were reviewed and assessed for accuracy of data collection. After training, the overall mean quality scores were higher for both the passive (95.3%; + 1.6% change) and interactive intervention groups (95.3%; + 0.9% change). Data collection accuracy improved modestly for the overall accuracy score and significantly for the substance identification component. There was little difference in accuracy measures between the different training methods. Despite the diversity of poison centers, data accuracy, specifically substance identification data fields, can be improved by developing a standardized, systematic, targeted, and mandatory training process. This process should be considered for training on other important topics, thus enhancing the value of these data in

Job satisfaction of radiologists in Germany. Status quo

International Nuclear Information System (INIS)

Beitzel, K.I.; Grosse, C.; Reiser, M.; Ertl-Wagner, B.; Ertl, L.

2011-01-01

Purpose: The aim of this study was to identify and evaluate the work-related satisfaction of radiologists and its influencing factors in Germany. Materials and Methods: For this purpose an invitational letter for an online opinion survey was sent to all member physicians of the Deutsche Roentgengesellschaft in 2008. 1200 questionnaires were completed (response rate 21 %) and evaluated statistically. Results: 81.7 % of radiologists declared themselves as being 'very' or 'rather satisfied'. The level of satisfaction was largely independent of age, gender, status, salary or family status. It increased over the last 5 years for 37.5 % of participants and decreased for 24.8 %. Nevertheless, 72 % of respondents indicated that they would not choose to specialize in radiology again. The main reason given was the workload. 65.6 % deemed it to be 'considerably' or 'rather too high'. Concomitantly, more than 70 % of respondents indicated that the workload had increased 'a lot' or 'rather'. Further reasons for not wanting to select the radiological profession again were 'unfavorable working hours' and 'unsatisfactory career perspectives'. Conclusion: The job satisfaction of radiologists in Germany is generally very high in spite of the perception of an extensive and frequently increasing workload. The high workload was the dominant factor against a renewed selection of the field of radiology. These data have to be interpreted in light of the current lack of residents and trained radiologists in Germany to counteract the trend toward emigration. (orig.)

Age determination of subdural hematomas: survey among radiologists.

Science.gov (United States)

Postema, F A M; Sieswerda-Hoogendoorn, Tessa; Majoie, C B L M; van Rijn, R R

2014-08-01

Abusive head trauma is a severe form of child abuse. One important diagnostic finding is the presence of a subdural hematoma. Age determination of subdural hematomas is important to relate radiological findings to the clinical history presented by the caregivers. In court this topic is relevant as dating subdural hematomas can lead to identification of a suspect. The aim of our study is to describe the current practice among radiologists in the Netherlands regarding the age determination of subdural hematomas in children. This is a cross-sectional study, describing the results of an online questionnaire regarding dating subdural hematomas among pediatric and neuro-radiologists in the Netherlands. The questionnaire consisted of sociodemographic questions, theoretical questions and eight pediatric cases in which the participants were asked to date subdural hematomas based on imaging findings. Fifty-one out of 172 radiologists (30 %) filled out the questionnaire. The percentage of participants that reported it was possible to date the subdural hematoma varied between 58 and 90 % for the eight different cases. In four of eight cases (50 %), the age of the subdural hematoma as known from clinical history fell within the range reported by the participants. None of the participants was "very certain" of their age determination. The results demonstrate that there is a considerable practice variation among Dutch radiologists regarding the age determination of subdural hematomas. This implicates that dating of subdural hematomas is not suitable to use in court, as no uniformity among experts exists.

The study of diagnostic accuracy of chest nodules by using different compression methods

International Nuclear Information System (INIS)

Liang Zhigang; Kuncheng, L.I.; Zhang Jinghong; Liu Shuliang

2005-01-01

Background: The purpose of this study was to compare the diagnostic accuracy of small nodules in the chest by using different compression methods. Method: Two radiologists with 5 years experience twice interpreted 39 chest images by using lossless and lossy compression methods. The time interval was 3 weeks. Each time the radiologists interpreted one kind of compressed images. The image browser used the Unisight software provided by Atlastiger Company in Shanghai. The interpreting results were analyzed by the ROCKIT software and the ROC curves were painted by Excel 2002. Results: In studies of receiver operating characteristics for scoring the presence or absence of nodules, the images with lossy compression method showed no statistical difference as compared with the images with lossless compression method. Conclusion: The diagnostic accuracy of chest nodules by using the lossless and lossy compression methods had no significant difference, we could use the lossy compression method to transmit and archive the chest images with nodules

Measuring and managing radiologist workload: measuring radiologist reporting times using data from a Radiology Information System

International Nuclear Information System (INIS)

Cowan, Ian A.; MacDonald, Sharon L.S.; Floyd, Richard A.

2013-01-01

Historically, there has been no objective method of measuring the time required for radiologists to produce reports during normal work. We have created a technique for semi-automated measurement of radiologist reporting time, and through it produced a robust set of absolute time requirements and relative value units for consultant reporting of diagnostic examinations in our hospital. A large sample of reporting times, recorded automatically by the Radiology Information System (COMRAD, Software Innovations, Christchurch, New Zealand) along with the description of each examination being reported, was placed in a database. Analysis was confined to diagnostic reporting by consultant radiologists. A spreadsheet was produced, listing the total number and the frequency of reporting times of each distinct examination. Outliers with exceptionally long report times (more than 10min for plain radiography, 30min for ultrasound, or 60min for CT or MRI with some exceptions) were culled; this removed 9.5% of the total. Complex CTs requiring separate workstation time were assigned times by consensus. The median time for the remainder of each sample was the assigned absolute reporting time in minutes and seconds. Relative value units were calculated using the reporting time for a single view department chest X-ray of 1min 38s including verifying a report made using speech recognition software. A schedule of absolute and relative values, based on over 179,000 reports, forms Table 2 of this paper. The technique provides a schedule of reporting times with reduced subjective input, which is more robust than existing systems for measuring reporting time.

Can CT and MR Shape and Textural Features Differentiate Benign Versus Malignant Pleural Lesions?

Science.gov (United States)

Pena, Elena; Ojiaku, MacArinze; Inacio, Joao R; Gupta, Ashish; Macdonald, D Blair; Shabana, Wael; Seely, Jean M; Rybicki, Frank J; Dennie, Carole; Thornhill, Rebecca E

2017-10-01

The study aimed to identify a radiomic approach based on CT and or magnetic resonance (MR) features (shape and texture) that may help differentiate benign versus malignant pleural lesions, and to assess if the radiomic model may improve confidence and accuracy of radiologists with different subspecialty backgrounds. Twenty-nine patients with pleural lesions studied on both contrast-enhanced CT and MR imaging were reviewed retrospectively. Three texture and three shape features were extracted. Combinations of features were used to generate logistic regression models using histopathology as outcome. Two thoracic and two abdominal radiologists evaluated their degree of confidence in malignancy. Diagnostic accuracy of radiologists was determined using contingency tables. Cohen's kappa coefficient was used to assess inter-reader agreement. Using optimal threshold criteria, sensitivity, specificity, and accuracy of each feature and combination of features were obtained and compared to the accuracy and confidence of radiologists. The CT model that best discriminated malignant from benign lesions revealed an AUC CT  = 0.92 ± 0.05 (P textural and shape analysis may help distinguish malignant from benign lesions. A radiomics-based approach may increase diagnostic confidence of abdominal radiologists on CT and MR and may potentially improve radiologists' accuracy in the assessment of pleural lesions characterized by MR. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Personal Branding: A Primer for Radiology Trainees and Radiologists.

Science.gov (United States)

Kalia, Vivek; Patel, Amy K; Moriarity, Andrew K; Canon, Cheri L

2017-07-01

A radiologist's personal brand is a composite of many parts in one's professional life. In an age where work quality and digital footprints are tracked and measured more than ever before, it behooves radiologists to develop and curate their own individual brands in effective ways. Personal branding consists of the decisions we make, both consciously and unconsciously, which affect our reputation and the likelihood of seeking our services in the future for both patients and referring providers. As hospital systems are increasingly adjusting their systems to cater to better patient experiences, it is imperative that radiologists similarly adjust our practice patterns to accommodate the needs of the new paradigm of value-based care. It is no longer sufficient to only practice excellent clinical radiology; one's service experience to clinical providers, report quality, and digital presence must all be robust and compelling. Defining your brand and promoting your vision and quality standards have become as important to radiologists' future as keeping up with advancements in radiologic technology. One must select the proper platforms and types of interactions in which to engage from available social media options. Developing a consistent brand and presence in the work setting, on social media accounts, and in professional organizations at the local, national, and international levels is the ultimate goal. At present, very little, if any, formal training is provided on personal branding skills such as these in current residency curricula, and it is critical for radiologists to fill their gaps in knowledge through additional means. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Medico-legal claims against English radiologists: 1995–2006

Science.gov (United States)

Halpin, S F S

2009-01-01

A list of claims against radiologists from 1995–2006 was obtained from the NHS Litigation Authority. It shows a total of 440 claims. The largest number of claims (199) related to delayed or missed diagnoses of cancer, and 73 claims related to breast radiology. There is a trend for a mild increase in the number of claims each year. 30 claims were made after a false-positive diagnosis of cancer. Just under £8.5 million has so far been paid in damages, with a further £5 million in legal fees. A claim for multiple missed diagnoses of breast cancer led to a pay-out of £464 000 (£673 000 after legal fees); the largest sum awarded following a delay in the diagnosis of an individual cancer was £300 000. The subtle legal distinction between error and negligence is reviewed here. The reason why breast radiologists are more likely to be sued than any other type of British radiologist is also discussed, along with the implications for UK radiological practice, particularly in light of the recent Chief Medical Officer's report on revalidation. A method is proposed that may protect radiologists from allegations of clinical negligence in the future. PMID:19470570

Who collects professional fees for neuroradiology interpretation, radiologists or nonradiologists?

Science.gov (United States)

Babiarz, Lukasz S; Yousem, David M; Parker, Laurence; Rao, Vijay

2012-07-01

An increasing portion of imaging studies are performed by nonradiologists, especially for modalities with the highest relative value units. The aim of this study was to examine the trends in neuroradiologic interpretation among radiologists, neurologists, neurosurgeons, and other specialists within the Medicare population. The number of neuroradiologic studies interpreted by radiologists, neurologists, neurosurgeons, and other specialists in the inpatient, hospital outpatient, and private office settings was determined from the CMS Physician/Supplier Procedure Summary Master Files for 1996 to 2010. Studies billed through professional and global charges were aggregated. Utilization rates and utilization rate compound annual growth rates were computed by specialty and by imaging study. In 1996, radiologists interpreted 4,802,490 (93.7%) CMS neuroradiologic procedures, neurologists 77,312 (1.5%), neurosurgeons 9,825 (0.19%), and other specialists 234,423 (4.6%). In 2010, radiologists interpreted 11,476,376 (93.5%) procedures, neurologists 101,172 (0.8%), neurosurgeons 20,697 (0.17%), and other specialists 680,786 (5.5%). Neurology and neurosurgery lost market share at all sites. Radiology's share increased in the inpatient (from 94.8% to 98.7%) and hospital outpatient (from 95% to 98.7%) settings but decreased in the private office setting (from 88.2% to 73.1%). Lost market share was captured by the other CMS specialty categories, including independent diagnostic testing facilities and multidisciplinary groups, many of which included radiologists. There was marked growth (140%) in neuroradiologic studies between 1996 and 2010 in the Medicare patient population. Radiologists' share of the total neuroradiologic interpretations remained unchanged and constituted 93.5% in 2010. Radiology's market share has shown growth in the inpatient and hospital outpatient sectors but not the private office sector, where independent diagnostic testing facilities, multidisciplinary

Value-Based Assessment of Radiology Reporting Using Radiologist-Referring Physician Two-Way Feedback System-a Design Thinking-Based Approach.

Science.gov (United States)

Shaikh, Faiq; Hendrata, Kenneth; Kolowitz, Brian; Awan, Omer; Shrestha, Rasu; Deible, Christopher

2017-06-01

In the era of value-based healthcare, many aspects of medical care are being measured and assessed to improve quality and reduce costs. Radiology adds enormously to health care costs and is under pressure to adopt a more efficient system that incorporates essential metrics to assess its value and impact on outcomes. Most current systems tie radiologists' incentives and evaluations to RVU-based productivity metrics and peer-review-based quality metrics. In a new potential model, a radiologist's performance will have to increasingly depend on a number of parameters that define "value," beginning with peer review metrics that include referrer satisfaction and feedback from radiologists to the referring physician that evaluates the potency and validity of clinical information provided for a given study. These new dimensions of value measurement will directly impact the cascade of further medical management. We share our continued experience with this project that had two components: RESP (Referrer Evaluation System Pilot) and FRACI (Feedback from Radiologist Addressing Confounding Issues), which were introduced to the clinical radiology workflow in order to capture referrer-based and radiologist-based feedback on radiology reporting. We also share our insight into the principles of design thinking as applied in its planning and execution.

Preliminary investigation of the interaction between radiologists and digital radiologic work stations

International Nuclear Information System (INIS)

Fajardo, L.L.; McNeill, K.M.; Maloney, K.; Mockbee, B.

1987-01-01

Using a work station built in the authors' department, they conducted an investigation into the interaction between radiologist and a digital radiologic work station. A survey provided information regarding the experience of 18 radiologists with digital technology and their expectations of its benefits. They ranked the potential attributes of digital work stations, with spatial resolution first, followed by contrast resolution, ease of use, speed, ease of learning, and cost. Observation of the radiologists' interaction with the work station has provided recommendations for implementation of functions. The authors conclude that radiologic work station user interfaces must be intuitive and support the radiologist's task without increasing the time or effort required for the task

A comparison of computer-assisted detection (CAD) programs for the identification of colorectal polyps: performance and sensitivity analysis, current limitations and practical tips for radiologists.

Science.gov (United States)

Bell, L T O; Gandhi, S

2018-06-01

To directly compare the accuracy and speed of analysis of two commercially available computer-assisted detection (CAD) programs in detecting colorectal polyps. In this retrospective single-centre study, patients who had colorectal polyps identified on computed tomography colonography (CTC) and subsequent lower gastrointestinal endoscopy, were analysed using two commercially available CAD programs (CAD1 and CAD2). Results were compared against endoscopy to ascertain sensitivity and positive predictive value (PPV) for colorectal polyps. Time taken for CAD analysis was also calculated. CAD1 demonstrated a sensitivity of 89.8%, PPV of 17.6% and mean analysis time of 125.8 seconds. CAD2 demonstrated a sensitivity of 75.5%, PPV of 44.0% and mean analysis time of 84.6 seconds. The sensitivity and PPV for colorectal polyps and CAD analysis times can vary widely between current commercially available CAD programs. There is still room for improvement. Generally, there is a trade-off between sensitivity and PPV, and so further developments should aim to optimise both. Information on these factors should be made routinely available, so that an informed choice on their use can be made. This information could also potentially influence the radiologist's use of CAD results. Copyright © 2018 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Accuracy improvement of irradiation data by combining ground and satellite measurements

Energy Technology Data Exchange (ETDEWEB)

Betcke, J. [Energy and Semiconductor Research Laboratory, Carl von Ossietzky University, Oldenburg (Germany); Beyer, H.G. [Department of Electrical Engineering, University of Applied Science (F.H.) Magdeburg-Stendal, Magdeburg (Germany)

2004-07-01

Accurate and site-specific irradiation data are essential input for optimal planning, monitoring and operation of solar energy technologies. A concrete example is the performance check of grid connected PV systems with the PVSAT-2 procedure. This procedure detects system faults in an early stage by a daily comparison of an individual reference yield with the actual yield. Calculation of the reference yield requires hourly irradiation data with a known accuracy. A field test of the predecessing PVSAT-1 procedure showed that the accuracy of the irradiation input is the determining factor for the overall accuracy of the yield calculation. In this paper we will investigate if it is possible to improve the accuracy of sitespeci.c irradiation data by combining accurate localised pyranometer data with semi-continuous satellite data.We will therefore introduce the ''Kriging of Differences'' data fusion method. Kriging of Differences also offers the possibility to estimate it's own accuracy. The obtainable accuracy gain and the effectiveness of the accuracy prediction will be investigated by validation on monthly and daily irradiation datasets. Results will be compared with the Heliosat method and interpolation of ground data. (orig.)

The Proposed MACRA/MIPS Threshold for Patient-Facing Encounters: What It Means for Radiologists.

Science.gov (United States)

Rosenkrantz, Andrew B; Hirsch, Joshua A; Allen, Bibb; Wang, Wenyi; Hughes, Danny R; Nicola, Gregory N

2017-03-01

In implementing the Merit-Based Incentive Payment System (MIPS), CMS will provide special considerations to physicians with infrequent face-to-face patient encounters by reweighting MIPS performance categories to account for the unique circumstances facing these providers. The aim of this study was to determine the impact of varying criteria on the fraction of radiologists who are likely to receive special considerations for performance assessment under MIPS. Data from the 2014 Medicare Physician and Other Supplier file for 28,710 diagnostic radiologists were used to determine the fraction of radiologists meeting various proposed criteria for receiving special considerations. For each definition, the fraction of patient-facing encounters among all billed codes was determined for those radiologists not receiving special considerations. When using the criterion proposed by CMS that physicians will receive special considerations if billing ≤25 evaluation and management services or surgical codes, 72.0% of diagnostic radiologists would receive special considerations, though such encounters would represent only 2.1% of billed codes among remaining diagnostic radiologists without special considerations. If CMS were to apply an alternative criterion of billing ≤100 evaluation and management codes exclusively, 98.8% of diagnostic radiologists would receive special considerations. At this threshold, patient-facing encounters would represent approximately 10% of billed codes among remaining radiologists without special considerations. The current CMS proposed criterion for special considerations would result in a considerable fraction of radiologists being evaluated on the basis of measures that are not reflective of their practice and beyond their direct control. Alternative criteria could help ensure that radiologists are provided a fair opportunity for success in performance review under the MIPS. Copyright © 2016 American College of Radiology. Published by Elsevier

Radiologists and Social Media: Do Not Forget About Facebook.

Science.gov (United States)

Seidel, Rebecca L; Jalilvand, Aryan; Kunjummen, Jean; Gilliland, Lea; Duszak, Richard

2018-01-01

Facebook (Facebook, Inc, Menlo Park, California, USA) is the most popular social networking platform worldwide. Facebook groups are virtual communities of people who share a common interest. Breast Imaging Radiologists is a Facebook group for radiologists with an interest in breast imaging. The purpose of this study was to analyze the membership and activity of the Breast Imaging Radiologists Facebook group (BIRFG) for 2 years since its inception. Using both the Grytics (www.grytics.com) and Sociograph (www.sociograph.io) analytic engines, the activity of the BIRFG was analyzed retrospectively from its inception on February 11, 2015, through February 12, 2017. Activity data were exported for further qualitative and quantitative analysis using Excel (Microsoft, Redmond, Washington, USA). Member demographic data were obtained by querying public Facebook profiles, US News Doctor Finder (US News & World Report, Washington, DC, USA), Doximity (Doximity, San Francisco, California, USA), and Google (Google Inc, Mountain View, California, USA). Membership grew from 1 to 774 over the study period, and 84% of the members were female. There were 493 posts, 3,253 comments, and 1,732 reactions; 92% of posts received either comments or reactions. Each post received an average of 6.6 comments, and 55% of members were active over the study period. There was an increase in all measures of activity from year 1 to year 2. Our findings indicate that radiologists find value in using Facebook groups as a forum to network and exchange information about breast imaging. This may be generalizable to other radiology subspecialties. Given the popularity and accessibility of Facebook for personal use, it may prove a more comfortable social medium for radiologists to interact professionally. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

On occupational-appointment demands on radiation hygiene for medical radiologists

International Nuclear Information System (INIS)

Usol'tsev, V.I.; Kuzin, V.I.; Tselikov, N.V.

1988-01-01

The aim of the work was to determine occupational requirements on radiation hygiene for medical radiologists. To solve the problem using questionnaire, personal conversations with doctors, analysis of basis control and examinations volume and character of work on radiation hygiene were studied in 510 medical radiologists. Occupational requirements for these specialists were worked out on the basis the obtained data. 4 refs

How patients can improve the accuracy of their medical records.

Science.gov (United States)

Dullabh, Prashila M; Sondheimer, Norman K; Katsh, Ethan; Evans, Michael A

2014-01-01

Assess (1) if patients can improve their medical records' accuracy if effectively engaged using a networked Personal Health Record; (2) workflow efficiency and reliability for receiving and processing patient feedback; and (3) patient feedback's impact on medical record accuracy. Improving medical record' accuracy and associated challenges have been documented extensively. Providing patients with useful access to their records through information technology gives them new opportunities to improve their records' accuracy and completeness. A new approach supporting online contributions to their medication lists by patients of Geisinger Health Systems, an online patient-engagement advocate, revealed this can be done successfully. In late 2011, Geisinger launched an online process for patients to provide electronic feedback on their medication lists' accuracy before a doctor visit. Patient feedback was routed to a Geisinger pharmacist, who reviewed it and followed up with the patient before changing the medication list shared by the patient and the clinicians. The evaluation employed mixed methods and consisted of patient focus groups (users, nonusers, and partial users of the feedback form), semi structured interviews with providers and pharmacists, user observations with patients, and quantitative analysis of patient feedback data and pharmacists' medication reconciliation logs. (1) Patients were eager to provide feedback on their medications and saw numerous advantages. Thirty percent of patient feedback forms (457 of 1,500) were completed and submitted to Geisinger. Patients requested changes to the shared medication lists in 89 percent of cases (369 of 414 forms). These included frequency-or dosage changes to existing prescriptions and requests for new medications (prescriptions and over-the counter). (2) Patients provided useful and accurate online feedback. In a subsample of 107 forms, pharmacists responded positively to 68 percent of patient requests for

Main lines of reorganization of the system of postgraduate training of radiologists

International Nuclear Information System (INIS)

Pavlov, A.S.; Kostromina, K.N.; Datsenko, V.S.

1988-01-01

The authors have summed up the experience accumulated over 20 years at the Chair of Clinical Radiology of the Central Order of Lenin Institute of Advanced Medical Training. Doctors majoring in this field, usually radiologists at the age over 35 when their creative initiative is on a decrease. Therfore the authors have proposed numerous measures aimed at the improvement of the system of training in radiology and an increase in the number of young specialists

Deciding why and when to use CT in children: a radiologist's perspective

International Nuclear Information System (INIS)

Frush, Donald P.

2014-01-01

Defining what is appropriate or inappropriate with respect to CT scanning is challenging. There are a variety of influences on scan utilization in children, some more widely recognized and acknowledged than others. It is important to understand the contribution of these elements as we move toward improved utilization. This must be through partnerships and shared efforts and accountability. These efforts include improved resources such as consensus appropriateness criteria and guidelines including decision rules and support. But there also need to be trench-based strategies on the part of practicing radiologists to model cooperative behavior rather than blame-centered behavior. (orig.)

Improving orbit prediction accuracy through supervised machine learning

Science.gov (United States)

Peng, Hao; Bai, Xiaoli

2018-05-01

Due to the lack of information such as the space environment condition and resident space objects' (RSOs') body characteristics, current orbit predictions that are solely grounded on physics-based models may fail to achieve required accuracy for collision avoidance and have led to satellite collisions already. This paper presents a methodology to predict RSOs' trajectories with higher accuracy than that of the current methods. Inspired by the machine learning (ML) theory through which the models are learned based on large amounts of observed data and the prediction is conducted without explicitly modeling space objects and space environment, the proposed ML approach integrates physics-based orbit prediction algorithms with a learning-based process that focuses on reducing the prediction errors. Using a simulation-based space catalog environment as the test bed, the paper demonstrates three types of generalization capability for the proposed ML approach: (1) the ML model can be used to improve the same RSO's orbit information that is not available during the learning process but shares the same time interval as the training data; (2) the ML model can be used to improve predictions of the same RSO at future epochs; and (3) the ML model based on a RSO can be applied to other RSOs that share some common features.

Research by pediatric radiologists - past accomplishments and future opportunities

International Nuclear Information System (INIS)

Effmann, E.L.

1987-01-01

Pediatric radiologists have made numerous and important contributions to the body of medical knowledge. This essay reviews aspects of biomedical and radiological research, analyses the state of scholarship in pediatric radiology today, and examines future research opportunities. The author's research interest in cardiopulmonary malformations and in the use of murine models of human disease serve to illustrate of but one of many investigative areas open to academic pediatric radiologists. Finally, the application process for NIH funding is briefly discussed. (orig.)

Reading a radiologist's mind: monitoring rising and falling interest levels while scanning chest x-rays

Science.gov (United States)

Alzubaidi, Mohammad; Patel, Ameet; Panchanathan, Sethuraman; Black, John A., Jr.

2010-02-01

Radiological images constitute a special class of images that are captured (or computed) specifically for the purpose of diagnosing patients. However, because these are not "natural" images, radiologists must be trained to interpret them through a process called "perceptual learning". However, because perceptual learning is implicit, experienced radiologists may sometimes find it difficult to explicitly (i.e. verbally) train less experienced colleagues. As a result, current methods of training can take years before a new radiologist is fully competent to independently interpret medical images. We hypothesize that eye tracking technology (coupled with multimedia technology) can be used to accelerate the process of perceptual training, through a Hebbian learning process. This would be accomplished by providing a radiologist-in-training with real-time feedback as he/she is fixating on important regions of an image. Of course this requires that the training system have information about what regions of an image are important - information that could presumably be solicited from experienced radiologists. However, our previous work has suggested that experienced radiologists are not always aware of those regions of an image that attract their attention, but are not clinically significant - information that is very important to a radiologist in training. This paper discusses a study in which local entropy computations were done on scan path data, and were found to provide a quantitative measure of the moment-by-moment interest level of radiologists as they scanned chest x-rays. The results also showed a striking contrast between the moment-by-moment deployment of attention between experienced radiologists and radiologists in training.

Mergers and acquisitions for the radiologist.

Science.gov (United States)

Fleishon, Howard B

2008-05-01

In 2006 and the first half of 2007, the rapid pace of global activity contributed to the popularity of mergers and acquisitions (M&A). In fact, the medical imaging industry has a significant history in M&A as well. Along with the expectation of continued growth in medical imaging utilization and other industry trends, radiologists may become more involved in M&A transactions. There is little in the radiology literature dealing with the logistics and pitfalls of M&A. This article is an introduction for radiologists who might consider buying or selling their practices or merging with strategic partners. Although there are significant differences in the approaches of buy or sell situations compared with mergers, they do share several concepts that are outlined. One key to success in M&A transactions is the "process" or approach, which is described with some practical guidelines. Some basic terms and suggestions are also presented for reference.

Improvement of the accuracy of phase observation by modification of phase-shifting electron holography

International Nuclear Information System (INIS)

Suzuki, Takahiro; Aizawa, Shinji; Tanigaki, Toshiaki; Ota, Keishin; Matsuda, Tsuyoshi; Tonomura, Akira

2012-01-01

We found that the accuracy of the phase observation in phase-shifting electron holography is strongly restricted by time variations of mean intensity and contrast of the holograms. A modified method was developed for correcting these variations. Experimental results demonstrated that the modification enabled us to acquire a large number of holograms, and as a result, the accuracy of the phase observation has been improved by a factor of 5. -- Highlights: ► A modified phase-shifting electron holography was proposed. ► The time variation of mean intensity and contrast of holograms were corrected. ► These corrections lead to a great improvement of the resultant phase accuracy. ► A phase accuracy of about 1/4000 rad was achieved from experimental results.

Follow up on a workloaded interventional radiologist's occupational radiation doses - a study case

International Nuclear Information System (INIS)

Ketner, D.; Ofer, A.; Engel, A.

2004-01-01

During many interventional procedures, patients' radiation doses are high, affecting radiologist's radiation doses. We checked occupational doses of a workloaded interventional radiologist during seven years

Mortality of British radiologists. A lecture Note+

International Nuclear Information System (INIS)

Doll, R.

2005-01-01

The precautions introduced after the first 23 years experience of the use of x-rays for medical diagnosis proved adequate to eliminate the acute hazards of exposure, but it was much longer before it was realized that small doses that did not produce any acute effect could increase the risk of cancer. British radiologists who took up the specialty at different periods have, therefore, been studied to see if the risk has now been adequately controlled. Four groups have been studied starting respectively before 1921, in 1921-34, 1935-54, and 1955-77, corresponding approximately to periods when different limits of exposure were applied. Altogether 2698 male radiologists have been identified and all but 27 followed successfully to emigration, death, or survival to January 1 st 1997. Of the 1198 who had died, 228 are known to have died of cancer. Two problems arise in evaluating the carcinogenic hazard to which they were exposed: the assessment of the doses received and the selection of an appropriate control group with which to compare their mortality. The most appropriate comparison group would seem to be medical practitioners in general. In comparison with them, radiologists entering in the first 3 periods had increased risks of death from cancer though appreciably less than would have been predicted from the expected effect of the radiation they had received. Those who joined in the latest period had a relatively reduced risk, irrespective of any effect of the small dose of radiation they are likely to have received. Independent evidence suggests, however, that since 1951 radiologists have smoked less than other doctors and the lower than predicted risk in the groups exposed since 1920 is limited to smoking related cancers, the mortality from other cancers being higher than in doctors generally. In assessing the risk of occupational exposure to radiation, life-style has to be taken into consideration, as well as dose of radiation. (author)

Is direct radiologist supervision of abdominal computed tomography (CT) scans necessary?

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Goh, V. [Department of Clinical Radiology, Northwick Park and St Mark' s Hospitals, Harrow (United Kingdom); Paul Strickland Scanner Centre, Mount Vernon Hospital, Northwood (United Kingdom); Halligan, S. [Department of Clinical Radiology, Northwick Park and St Mark' s Hospitals, Harrow (United Kingdom)]. E-mail: s.halligan@imperial.ac.uk; Anderson, J.M. [Department of Clinical Radiology, Northwick Park and St Mark' s Hospitals, Harrow (United Kingdom); Hugill, J. [Department of Clinical Radiology, Northwick Park and St Mark' s Hospitals, Harrow (United Kingdom); Leonard, A. [Department of Clinical Radiology, Northwick Park and St Mark' s Hospitals, Harrow (United Kingdom)

2005-07-01

AIM: To determine the effect of direct radiological supervision of patients attending for abdominal CT by assessing the frequency of protocol alteration subsequent to radiologist review of the images obtained. MATERIALS AND METHODS: A prospective questionnaire-based observational study was performed of 187 consecutive patients undergoing abdominal CT. The CT protocol was determined by a radiologist in advance, with reference to the request form. Any subsequent change in the prescribed study that was contingent on radiologist review of the images obtained was documented on the questionnaire. Comparison was made with a second (control) group of 100 patients undergoing cranial CT. RESULTS: A protocol change was undertaken following radiologist review of the CT images of 17 (9%) of the group undergoing abdominal CT, compared with 14 (14%) of the group undergoing cranial CT. In the abdominal CT group, further scanning was performed for lesion characterization, to guide a subsequent interventional procedure, because of inadequate anatomical coverage or to evaluate an unexpected lung tumour. There was no significant difference in proportions between the two groups (p=0.23). CONCLUSION: When abdominal and cranial CT studies were compared, there was no significant difference in the proportion of studies requiring a change in the prescribed protocol following radiologist review of the images obtained. There was no evidence to suggest that abdominal CT was any less suited to protocol.

Evaluation of accuracy and interobserver agreement of MR cholangiography for diagnosis of cholelithiasis

International Nuclear Information System (INIS)

Park, Sung Won; Baek, Seung Yon; Kang, Byung Chul; Rhee, Chung Sik

2001-01-01

To assess the accuracy of MR cholangiography(MRC) in the diagnosis of cholelithiasis, and to determine interobserver agreement. Between March and September 1999, 43 consecutive patients with biliary obstruction [24 men and 19 women aged 25-85 (mean, 58) years] underwent MRC using the single-shot fast spin-echo technique. Heavily T2-weighted source images(axial and coronal) 3-5 mm thick and 12 projection images with 15- degree rotation and 5-cm thickness were obtained. All images were reviewed blindly and independently by two radiologists specialized in the interpretation of abdominal imaging information. Choledocholithiasis was evaluated in eight segments of the intrahepatic duct(IHD), extrahepatic duct(EHD) and gall bladder lumen. Final diagnosis was established on the basis of operative (n=31) and other radiological (n=12) findings. The sensitivity, specificity and accuracy of the MRC findings were assessed, and using kappa measurement (cross-table analysis, SPSS Windows for 8.0), interobserver agreement was determined. Thirty of the 43 patients, had choledocholithiasis (IHD stones in 7 cases, EHD stones in 15, and GB stones in 18). For radiologist 1, sensitivity, specificity and accuracy were 86%, 100% and 98%, respectively, in the diagnosis of IHD stones; 100%, 89% and 93%, respectively, in the diagnosis of EHD stones; and 81%, 96% and 91%, respectively, in the diagnosis of GB stones. For radiologist 2, the corresponding figures were 86%, 94% and 93% (1HD stones);87%, 89% and 88% (EHD stones); and 81%, 86% and 84% (GB stones). Interobserver agreement for the diagnosis of choledocholithiasis was excellent in all cases. The kappa mesurement was 0.91 for 1HD stones, 0.77 for EHD stones, and 0.70 for GB stones. MRC is an excellent imaging modality for the diagnosis of choledocholithiasis, and inter observer agreement was also excellent

Automated registration of diagnostic to prediagnostic x-ray mammograms: Evaluation and comparison to radiologists' accuracy

International Nuclear Information System (INIS)

Pinto Pereira, Snehal M.; Hipwell, John H.; McCormack, Valerie A.; Tanner, Christine; Moss, Sue M.; Wilkinson, Louise S.; Khoo, Lisanne A. L.; Pagliari, Catriona; Skippage, Pippa L.; Kliger, Carole J.; Hawkes, David J.; Santos Silva, Isabel M. dos

2010-01-01

Purpose: To compare and evaluate intensity-based registration methods for computation of serial x-ray mammogram correspondence. Methods: X-ray mammograms were simulated from MRIs of 20 women using finite element methods for modeling breast compressions and employing a MRI/x-ray appearance change model. The parameter configurations of three registration methods, affine, fluid, and free-form deformation (FFD), were optimized for registering x-ray mammograms on these simulated images. Five mammography film readers independently identified landmarks (tumor, nipple, and usually two other normal features) on pairs of diagnostic and corresponding prediagnostic digitized images from 52 breast cancer cases. Landmarks were independently reidentified by each reader. Target registration errors were calculated to compare the three registration methods using the reader landmarks as a gold standard. Data were analyzed using multilevel methods. Results: Between-reader variability varied with landmark (p<0.01) and screen (p=0.03), with between-reader mean distance (mm) in point location on the diagnostic/prediagnostic images of 2.50 (95% CI 1.95, 3.15)/2.84 (2.24, 3.55) for nipples and 4.26 (3.43, 5.24)/4.76 (3.85, 5.84) for tumors. Registration accuracy was sensitive to the type of landmark and the amount of breast density. For dense breasts (≥40%), the affine and fluid methods outperformed FFD. For breasts with lower density, the affine registration surpassed both fluid and FFD. Mean accuracy (mm) of the affine registration varied between 3.16 (95% CI 2.56, 3.90) for nipple points in breasts with density 20%-39% and 5.73 (4.80, 6.84) for tumor points in breasts with density <20%. Conclusions: Affine registration accuracy was comparable to that between independent film readers. More advanced two-dimensional nonrigid registration algorithms were incapable of increasing the accuracy of image alignment when compared to affine registration.

Accuracy improvement techniques in Precise Point Positioning method using multiple GNSS constellations

Science.gov (United States)

Vasileios Psychas, Dimitrios; Delikaraoglou, Demitris

2016-04-01

The future Global Navigation Satellite Systems (GNSS), including modernized GPS, GLONASS, Galileo and BeiDou, offer three or more signal carriers for civilian use and much more redundant observables. The additional frequencies can significantly improve the capabilities of the traditional geodetic techniques based on GPS signals at two frequencies, especially with regard to the availability, accuracy, interoperability and integrity of high-precision GNSS applications. Furthermore, highly redundant measurements can allow for robust simultaneous estimation of static or mobile user states including more parameters such as real-time tropospheric biases and more reliable ambiguity resolution estimates. This paper presents an investigation and analysis of accuracy improvement techniques in the Precise Point Positioning (PPP) method using signals from the fully operational (GPS and GLONASS), as well as the emerging (Galileo and BeiDou) GNSS systems. The main aim was to determine the improvement in both the positioning accuracy achieved and the time convergence it takes to achieve geodetic-level (10 cm or less) accuracy. To this end, freely available observation data from the recent Multi-GNSS Experiment (MGEX) of the International GNSS Service, as well as the open source program RTKLIB were used. Following a brief background of the PPP technique and the scope of MGEX, the paper outlines the various observational scenarios that were used in order to test various data processing aspects of PPP solutions with multi-frequency, multi-constellation GNSS systems. Results from the processing of multi-GNSS observation data from selected permanent MGEX stations are presented and useful conclusions and recommendations for further research are drawn. As shown, data fusion from GPS, GLONASS, Galileo and BeiDou systems is becoming increasingly significant nowadays resulting in a position accuracy increase (mostly in the less favorable East direction) and a large reduction of convergence

The radiologist's responsibilities for the radiation protection of patients

International Nuclear Information System (INIS)

Etard, C.

2010-01-01

The obligations of the radiologist for the radiation protection of patients include a review of the appropriateness of the examination and optimization of the protocol. Both internal and external quality assurance programs are mandatory. The specific tasks and their frequency are defined by the AFSSAPS. The radiology report of procedures performed over radiosensitive regions must include the delivered dose. The imaging technique must be optimized based on published guidelines or law for the most frequent examinations. All radiologists should be familiar with radiation protection. Incidents should be reported to the Nuclear Safety Authority. (author)

Role of the radiologist in the management of pain

International Nuclear Information System (INIS)

Quinn, S.F.; Murtagh, F.R.; Chatfield, R.; Kori, S.; Kavanagh, J.; Clark, R.A.

1987-01-01

Radiologists are taking an expanding role in the management of pain. The procedures most commonly used at our institution are facet blocks, peripheral nerve blocks, peripheral nerve ablations, ganglion ablations, chemoinfusions, chemoembolizations, and embolizations alone. CT is used for the facet, ganglion, and peripheral nerve procedures. The techniques for these procedures will be stressed, as meticulous technique is imperative. The radiologist must work closely with the attending clinician to determine both the neurologic level and to monitor therapy. The University of South Florida pain team flow sheet and pain evaluation method is presented

The Improvement of Behavior Recognition Accuracy of Micro Inertial Accelerometer by Secondary Recognition Algorithm

Directory of Open Access Journals (Sweden)

Yu Liu

2014-05-01

Full Text Available Behaviors of “still”, “walking”, “running”, “jumping”, “upstairs” and “downstairs” can be recognized by micro inertial accelerometer of low cost. By using the features as inputs to the well-trained BP artificial neural network which is selected as classifier, those behaviors can be recognized. But the experimental results show that the recognition accuracy is not satisfactory. This paper presents secondary recognition algorithm and combine it with BP artificial neural network to improving the recognition accuracy. The Algorithm is verified by the Android mobile platform, and the recognition accuracy can be improved more than 8 %. Through extensive testing statistic analysis, the recognition accuracy can reach 95 % through BP artificial neural network and the secondary recognition, which is a reasonable good result from practical point of view.

Improvement of the accuracy of phase observation by modification of phase-shifting electron holography

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Takahiro; Aizawa, Shinji; Tanigaki, Toshiaki [Advanced Science Institute, RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Ota, Keishin, E-mail: ota@microphase.co.jp [Microphase Co., Ltd., Onigakubo 1147-9, Tsukuba, Ibaragi 300-2651 (Japan); Matsuda, Tsuyoshi [Japan Science and Technology Agency, Kawaguchi-shi, Saitama 332-0012 (Japan); Tonomura, Akira [Advanced Science Institute, RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Okinawa Institute of Science and Technology, Graduate University, Kunigami, Okinawa 904-0495 (Japan); Central Research Laboratory, Hitachi, Ltd., Hatoyama, Saitama 350-0395 (Japan)

2012-07-15

We found that the accuracy of the phase observation in phase-shifting electron holography is strongly restricted by time variations of mean intensity and contrast of the holograms. A modified method was developed for correcting these variations. Experimental results demonstrated that the modification enabled us to acquire a large number of holograms, and as a result, the accuracy of the phase observation has been improved by a factor of 5. -- Highlights: Black-Right-Pointing-Pointer A modified phase-shifting electron holography was proposed. Black-Right-Pointing-Pointer The time variation of mean intensity and contrast of holograms were corrected. Black-Right-Pointing-Pointer These corrections lead to a great improvement of the resultant phase accuracy. Black-Right-Pointing-Pointer A phase accuracy of about 1/4000 rad was achieved from experimental results.

Integrating machine learning and physician knowledge to improve the accuracy of breast biopsy.

Science.gov (United States)

Dutra, I; Nassif, H; Page, D; Shavlik, J; Strigel, R M; Wu, Y; Elezaby, M E; Burnside, E

2011-01-01

In this work we show that combining physician rules and machine learned rules may improve the performance of a classifier that predicts whether a breast cancer is missed on percutaneous, image-guided breast core needle biopsy (subsequently referred to as "breast core biopsy"). Specifically, we show how advice in the form of logical rules, derived by a sub-specialty, i.e. fellowship trained breast radiologists (subsequently referred to as "our physicians") can guide the search in an inductive logic programming system, and improve the performance of a learned classifier. Our dataset of 890 consecutive benign breast core biopsy results along with corresponding mammographic findings contains 94 cases that were deemed non-definitive by a multidisciplinary panel of physicians, from which 15 were upgraded to malignant disease at surgery. Our goal is to predict upgrade prospectively and avoid surgery in women who do not have breast cancer. Our results, some of which trended toward significance, show evidence that inductive logic programming may produce better results for this task than traditional propositional algorithms with default parameters. Moreover, we show that adding knowledge from our physicians into the learning process may improve the performance of the learned classifier trained only on data.

Your Radiologist Explains Magnetic Resonance Angiography (MRA)

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Full Text Available ... to Radiology Info dot org Hello, I’m Dr. Elliot Fishman, a radiologist at Johns Hopkins Hospital ... of your body and to identify abnormalities and disease. If you’re scheduled for an MRA scan, ...

Your Radiologist Explains Magnetic Resonance Angiography (MRA)

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Full Text Available ... Angiography (MRA) Transcript Welcome to Radiology Info dot org Hello, I’m Dr. Elliot Fishman, a radiologist ... question you might have, visit Radiology Info dot org. Thank you for your time and for your ...

Your Radiologist Explains Magnetic Resonance Angiography (MRA)

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Full Text Available ... An MRI Story Radiology and You Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography ( ... posted: How to Obtain and Share Your Medical Images Movement Disorders Video: The Basketball Game: An MRI ...

Experiences with a self-test for Dutch breast screening radiologists: lessons learnt

NARCIS (Netherlands)

Timmers, J. M. H.; Verbeek, A. L. M.; Pijnappel, R. M.; Broeders, M. J. M.; den Heeten, G. J.

2014-01-01

To evaluate a self-test for Dutch breast screening radiologists introduced as part of the national quality assurance programme. A total of 144 radiologists were invited to complete a test-set of 60 screening mammograms (20 malignancies). Participants assigned findings such as location, lesion type

Assessment of deep myometrial invasion of endometrial cancer on MRI: added value of second-opinion interpretations by radiologists subspecialized in gynaecologic oncology.

Science.gov (United States)

Woo, Sungmin; Kim, Sang Youn; Cho, Jeong Yeon; Kim, Seung Hyup

2017-05-01

To investigate the added value of secondary reports issued by radiologists subspecializing in gynaecologic imaging for determining deep myometrial invasion of endometrial cancer on MRI. Initial (from referring institutions) and secondary (by subspecialized radiologists) interpretations of MRI of 55 patients with endometrial cancer were retrospectively reviewed. A radiologist blinded to clinicopathological information assessed both reports for the presence of deep myometrial invasion. Reference standard was based on hysterectomy specimens. Kappa coefficients (k) were used to measure their concordance. McNemar testing and receiver operating characteristic (ROC) analysis was used to compare sensitivities, specificities and areas under the curves (AUCs). Deep myometrial invasion was present in 25 (45.5 %) patients. Among 27.3 % (15/55; k = 0.458) patients with discrepant results, secondary interpretations were correct in 10 (66.7 %) cases. Sensitivity was higher in secondary than in initial reports (76.0 % vs. 48.0 %, p = 0.039) while no significant difference was seen in specificity (70.0 % vs. 76.7 %, p = 0.668). At ROC analysis, there was a tendency for higher AUCs in secondary reports (0.785 vs 0.669, p = 0.096). Secondary readings of MRI by subspecialized gynaecologic oncologic radiologists may provide incremental value in determining deep myometrial invasion of endometrial cancer. • Deep myometrial invasion is an important prognostic factor in endometrial cancer. • Assessment of deep myometrial invasion is often discrepant between initial and secondary reports. • Secondary reports showed higher sensitivity and accuracy. • Secondary review of MRI may provide incremental value in endometrial cancer patients.

We have much in common: the similar inter-generational work preferences and career satisfaction among practicing radiologists.

Science.gov (United States)

Moriarity, Andrew K; Brown, Manuel L; Schultz, Lonni R

2014-04-01

There are many reported generational differences regarding workplace motivators, but these have not been previously studied in radiologists. The aim of this study was to assess for generational differences in workplace satisfaction and desired workplace characteristics among practicing radiologists. An electronic survey distributed to ACR, Society of Chairs of Academic Radiology Departments, and Association of Program Directors in Radiology members generated 1,577 responses from baby boom (BG) and generation X (GX) radiologists in active practice. Nineteen workplace characteristics and their associations with workplace satisfaction were tested in a univariate analysis using χ(2) tests and in a multiple logistic regression model to test for associations with satisfaction. Workplace satisfaction among BG and GX radiologists was 78% and 80%, respectively. Both generations reported higher satisfaction if they were optimistic about the future of radiology (87% of BG vs 85% of GX radiologists), believed the difference in the desired versus expected age of retirement was narrow (1.5 ± 3.3 years for BG radiologists vs 3.0 ± 4.1 years for GX radiologists), felt that social interactions in the workplace were important (81% of BG vs 83% of GX radiologists), and believed that professionalism in their peers was important (79% of BG vs 82% of GX radiologists). BG radiologists were more satisfied if they valued staff diversity, while GX radiologists were more satisfied if they felt that job security and the amount of compensation were important. There was no significant association of satisfaction with generation, gender, practice setting, or additional administrative work. Workplace satisfaction among practicing radiologists remains high but has decreased compared with prior surveys. The two dominant generations of practicing radiologists have similar workplace satisfaction rates and desired workplace characteristics. Copyright © 2014 American College of Radiology. Published

Algorithm 589. SICEDR: a FORTRAN subroutine for improving the accuracy of computed matrix eigenvalues

International Nuclear Information System (INIS)

Dongarra, J.J.

1982-01-01

SICEDR is a FORTRAN subroutine for improving the accuracy of a computed real eigenvalue and improving or computing the associated eigenvector. It is first used to generate information during the determination of the eigenvalues by the Schur decomposition technique. In particular, the Schur decomposition technique results in an orthogonal matrix Q and an upper quasi-triangular matrix T, such that A = QTQ/sup T/. Matrices A, Q, and T and the approximate eigenvalue, say lambda, are then used in the improvement phase. SICEDR uses an iterative method similar to iterative improvement for linear systems to improve the accuracy of lambda and improve or compute the eigenvector x in O(n 2 ) work, where n is the order of the matrix A

Improvement on the accuracy of beam bugs in linear induction accelerator

International Nuclear Information System (INIS)

Xie Yutong; Dai Zhiyong; Han Qing

2002-01-01

In linear induction accelerator the resistive wall monitors known as 'beam bugs' have been used as essential diagnostics of beam current and location. The author presents a new method that can improve the accuracy of these beam bugs used for beam position measurements. With a fine beam simulation set, this method locates the beam position with an accuracy of 0.02 mm and thus can scale the beam bugs very well. Experiment results prove that the precision of beam position measurements can reach submillimeter degree

Training readers to improve their accuracy in grading Crohn's disease activity on MRI

International Nuclear Information System (INIS)

Tielbeek, Jeroen A.W.; Bipat, Shandra; Boellaard, Thierry N.; Nio, C.Y.; Stoker, Jaap

2014-01-01

To prospectively evaluate if training with direct feedback improves grading accuracy of inexperienced readers for Crohn's disease activity on magnetic resonance imaging (MRI). Thirty-one inexperienced readers assessed 25 cases as a baseline set. Subsequently, all readers received training and assessed 100 cases with direct feedback per case, randomly assigned to four sets of 25 cases. The cases in set 4 were identical to the baseline set. Grading accuracy, understaging, overstaging, mean reading times and confidence scores (scale 0-10) were compared between baseline and set 4, and between the four consecutive sets with feedback. Proportions of grading accuracy, understaging and overstaging per set were compared using logistic regression analyses. Mean reading times and confidence scores were compared by t-tests. Grading accuracy increased from 66 % (95 % CI, 56-74 %) at baseline to 75 % (95 % CI, 66-81 %) in set 4 (P = 0.003). Understaging decreased from 15 % (95 % CI, 9-23 %) to 7 % (95 % CI, 3-14 %) (P < 0.001). Overstaging did not change significantly (20 % vs 19 %). Mean reading time decreased from 6 min 37 s to 4 min 35 s (P < 0.001). Mean confidence increased from 6.90 to 7.65 (P < 0.001). During training, overall grading accuracy, understaging, mean reading times and confidence scores improved gradually. Inexperienced readers need training with at least 100 cases to achieve the literature reported grading accuracy of 75 %. (orig.)

Time Spent by Breast Imaging Radiologists to Perform Value-Added Activities at an Academic Cancer Center.

Science.gov (United States)

Collado-Mesa, Fernando; Klevos, Geetika; Arheart, Kristopher; Banks, James; Yepes, Monica; Net, Jose

2017-04-01

Health care reform in the United States has generated a paradigm shift in the practice of radiology aimed at increasing the degree of patient-centered care. We conducted a study to quantify the amount of time breast imaging radiologists spend on value-added activities at an academic comprehensive cancer center located in Miami, Florida, and accredited by the American College of Radiology as a Breast Imaging Center of Excellence. A prospective, observational study was conducted during a period of 20 consecutive workdays. Three participating breast imaging radiologists maintained a real-time log of each activity performed. A generalized linear model was used to perform a 1-way analysis of variance. An alpha level of .05 was used to determine statistical significance. The average daily time dedicated to these activities was 92.1 minutes (range, 56.4-132.2). The amount of time significantly differed among breast imaging radiologists and correlated with their assigned daily role (P value-added activities to help improve patients' experience across the continuity of their care. We propose that similar studies be conducted at other institutions to better assess the magnitude of this finding across different breast imaging care settings.

Improving Accuracy of Intrusion Detection Model Using PCA and optimized SVM

Directory of Open Access Journals (Sweden)

Sumaiya Thaseen Ikram

2016-06-01

Full Text Available Intrusion detection is very essential for providing security to different network domains and is mostly used for locating and tracing the intruders. There are many problems with traditional intrusion detection models (IDS such as low detection capability against unknown network attack, high false alarm rate and insufficient analysis capability. Hence the major scope of the research in this domain is to develop an intrusion detection model with improved accuracy and reduced training time. This paper proposes a hybrid intrusiondetection model by integrating the principal component analysis (PCA and support vector machine (SVM. The novelty of the paper is the optimization of kernel parameters of the SVM classifier using automatic parameter selection technique. This technique optimizes the punishment factor (C and kernel parameter gamma (γ, thereby improving the accuracy of the classifier and reducing the training and testing time. The experimental results obtained on the NSL KDD and gurekddcup dataset show that the proposed technique performs better with higher accuracy, faster convergence speed and better generalization. Minimum resources are consumed as the classifier input requires reduced feature set for optimum classification. A comparative analysis of hybrid models with the proposed model is also performed.

Your Radiologist Explains Magnetic Resonance Angiography (MRA)

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Full Text Available ... Sponsored by Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ... I’d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA ...

MRI of the prostate in Germany. Online survey among radiologists

Energy Technology Data Exchange (ETDEWEB)

Mueller-Lisse, U.G.; Reiser, M. [Univ. Munich (Germany). Dept. of Radiology; Lewerich, B. [Deutsche Roentgengesellschaft, Geschaeftsstelle, Berlin (Germany); Mueller-Lisse, U.L. [Interdisziplinaeres Onkologisches Zentrum Muenchen (IOZ) (Germany). Dept. of Urology; Scherr, M.K. [Berufsgenossenschaftliche Unfallklinik, Dept. of Radiology, Murnau (Germany)

2015-08-15

To assess structural, technical, and communicative aspects of dedicated MR examinations of the prostate (MRP) offered by radiologists in Germany. We conducted an eight-item online survey among members of the German Radiology Society (DRG). Radiological institutions were asked about their structure, i. e., either hospital department (HD) or private practice (PP), number of board-certified radiologists, postal regions, number of MRPs in 2011, MR technology and MR sequences applied, ways to communicate results, and feedback from referring physicians on results of subsequent tests and procedures. Submissions were cleared of redundancies and anonymized. Differences in the number of positive replies to each item were statistically significant at p < 0.05 for two-tailed testing in 2 x 2 tables. The survey represented board-certified radiologists in 128 institutions (63 HDs and 65 PPs) in 67/95 German postal regions (71 %). Almost two-thirds of institutions performed 11 to 50 MRPs in 2011, more often at 1.5 T (116/128, 91 %) than at 3.0 T (36/128, 28 %), and most frequently with surface coils (1.5 T, 88/116, 76 %; 3.0 T, 34/36, 94 %; chi-square, 1.9736, 0.1 < p < 0.25). About two-thirds of 1.5 T users and 90 % of 3.0 T users applied at least one functional MR modality (diffusion-weighted imaging, dynamic contrast-enhanced imaging, or MR spectroscopy) for MRP. Reports including graphic representations of the prostate were applied by 21/128 institutions (16 %). Clinical feedback after MRP to radiologists other than upon their own request was infrequent (HDs, 32 - 45 %, PPs, 18 - 32 %). MRP was a widely available, small-volume examination among radiologists in Germany in 2011. The technology mainstay was a 1.5 T surface coil examination including at least one functional MR modality. Dedicated reporting and feedback mechanisms for quality control were underdeveloped.

MRI of the prostate in Germany. Online survey among radiologists

International Nuclear Information System (INIS)

Mueller-Lisse, U.G.; Reiser, M.; Mueller-Lisse, U.L.

2015-01-01

To assess structural, technical, and communicative aspects of dedicated MR examinations of the prostate (MRP) offered by radiologists in Germany. We conducted an eight-item online survey among members of the German Radiology Society (DRG). Radiological institutions were asked about their structure, i. e., either hospital department (HD) or private practice (PP), number of board-certified radiologists, postal regions, number of MRPs in 2011, MR technology and MR sequences applied, ways to communicate results, and feedback from referring physicians on results of subsequent tests and procedures. Submissions were cleared of redundancies and anonymized. Differences in the number of positive replies to each item were statistically significant at p < 0.05 for two-tailed testing in 2 x 2 tables. The survey represented board-certified radiologists in 128 institutions (63 HDs and 65 PPs) in 67/95 German postal regions (71 %). Almost two-thirds of institutions performed 11 to 50 MRPs in 2011, more often at 1.5 T (116/128, 91 %) than at 3.0 T (36/128, 28 %), and most frequently with surface coils (1.5 T, 88/116, 76 %; 3.0 T, 34/36, 94 %; chi-square, 1.9736, 0.1 < p < 0.25). About two-thirds of 1.5 T users and 90 % of 3.0 T users applied at least one functional MR modality (diffusion-weighted imaging, dynamic contrast-enhanced imaging, or MR spectroscopy) for MRP. Reports including graphic representations of the prostate were applied by 21/128 institutions (16 %). Clinical feedback after MRP to radiologists other than upon their own request was infrequent (HDs, 32 - 45 %, PPs, 18 - 32 %). MRP was a widely available, small-volume examination among radiologists in Germany in 2011. The technology mainstay was a 1.5 T surface coil examination including at least one functional MR modality. Dedicated reporting and feedback mechanisms for quality control were underdeveloped.

WE-G-19A-01: Radiologists and Medical Physicists: Working Together to Achieve Common Goals

International Nuclear Information System (INIS)

Jones, A; Ma, J; Steele, J; Choi, H

2014-01-01

It is vitally important that medical physicists understand the clinical questions that radiologists are trying to answer with patient images. Knowledge of the types of information the radiologist needs helps medical physicists configure imaging protocols that appropriately balance radiation dose, time, and image quality. The ability to communicate with radiologists and understand medical terminology, anatomy, and physiology is key to creating such imaging protocols. In this session, radiologists will present clinical cases and describe the information they are seeking in the clinical images. Medical physicists will then discuss how imaging protocols are configured. Learning Objectives: Understand the types of information that radiologists seek in medical images. Apply this understanding in configuring the imaging equipment to deliver this information. Develop strategies for working with physician colleagues

WE-G-19A-01: Radiologists and Medical Physicists: Working Together to Achieve Common Goals

Energy Technology Data Exchange (ETDEWEB)

Jones, A; Ma, J; Steele, J; Choi, H [UT MD Anderson Cancer Center, Houston, TX (United States)

2014-06-15

It is vitally important that medical physicists understand the clinical questions that radiologists are trying to answer with patient images. Knowledge of the types of information the radiologist needs helps medical physicists configure imaging protocols that appropriately balance radiation dose, time, and image quality. The ability to communicate with radiologists and understand medical terminology, anatomy, and physiology is key to creating such imaging protocols. In this session, radiologists will present clinical cases and describe the information they are seeking in the clinical images. Medical physicists will then discuss how imaging protocols are configured. Learning Objectives: Understand the types of information that radiologists seek in medical images. Apply this understanding in configuring the imaging equipment to deliver this information. Develop strategies for working with physician colleagues.

Investigation of the interpolation method to improve the distributed strain measurement accuracy in optical frequency domain reflectometry systems.

Science.gov (United States)

Cui, Jiwen; Zhao, Shiyuan; Yang, Di; Ding, Zhenyang

2018-02-20

We use a spectrum interpolation technique to improve the distributed strain measurement accuracy in a Rayleigh-scatter-based optical frequency domain reflectometry sensing system. We demonstrate that strain accuracy is not limited by the "uncertainty principle" that exists in the time-frequency analysis. Different interpolation methods are investigated and used to improve the accuracy of peak position of the cross-correlation and, therefore, improve the accuracy of the strain. Interpolation implemented by padding zeros on one side of the windowed data in the spatial domain, before the inverse fast Fourier transform, is found to have the best accuracy. Using this method, the strain accuracy and resolution are both improved without decreasing the spatial resolution. The strain of 3 μϵ within the spatial resolution of 1 cm at the position of 21.4 m is distinguished, and the measurement uncertainty is 3.3 μϵ.

Questions of an otorhinolaryngologist to a radiologist

International Nuclear Information System (INIS)

Theopold, H.M.

1982-01-01

The otorhinolaryngologist expects the radiologist to answer very quickly in emergencies such as complications of inflammatory processes of the paranasal accessory sinuses, diseases, tumours, and skull traumatology. Aspects of conventional X-ray diagnosis, X-ray tomography, and computerized tomography are discussed. (APR) [de

A Least Squares Collocation Method for Accuracy Improvement of Mobile LiDAR Systems

Directory of Open Access Journals (Sweden)

Qingzhou Mao

2015-06-01

Full Text Available In environments that are hostile to Global Navigation Satellites Systems (GNSS, the precision achieved by a mobile light detection and ranging (LiDAR system (MLS can deteriorate into the sub-meter or even the meter range due to errors in the positioning and orientation system (POS. This paper proposes a novel least squares collocation (LSC-based method to improve the accuracy of the MLS in these hostile environments. Through a thorough consideration of the characteristics of POS errors, the proposed LSC-based method effectively corrects these errors using LiDAR control points, thereby improving the accuracy of the MLS. This method is also applied to the calibration of misalignment between the laser scanner and the POS. Several datasets from different scenarios have been adopted in order to evaluate the effectiveness of the proposed method. The results from experiments indicate that this method would represent a significant improvement in terms of the accuracy of the MLS in environments that are essentially hostile to GNSS and is also effective regarding the calibration of misalignment.

Job satisfaction, income, workload, workplace, and demographics of Japanese radiologists in the 2008 survey.

Science.gov (United States)

Sone, Miyuki; Mizunuma, Kimiyoshi; Nakajima, Yasuo; Yasunaga, Hideo; Ohtomo, Kuni

2013-05-01

This study aimed to verify radiologists' demographics and job satisfaction in Japan and analyze factors affecting job satisfaction. A self-administered questionnaire was mailed to 7,491 eligible radiologists between April and June 2008. The questionnaire consisted of items concerning participants' demographics and job satisfaction. A multivariate regression analysis was conducted to analyze the impact of practice environments on radiologists' overall job satisfaction. There were 3,986 (53 %) valid responses. In 2008, 67.7 % of radiologists reported being extremely or somewhat satisfied with their job. With regard to changes in job satisfaction over the previous 5 years, 45.8 % felt much increased or somewhat increased satisfaction, whereas 18.8 % felt somewhat decreased or much decreased. The significant factors associated with overall job satisfaction were annual income (p job satisfaction over 5 years were interest and lifestyle, whereas the strongest reason for decreasing job satisfaction was workload. This survey revealed Japanese radiologists had a high level of job satisfaction.

The U.S. Radiologist Workforce: An Analysis of Temporal and Geographic Variation by Using Large National Datasets.

Science.gov (United States)

Rosenkrantz, Andrew B; Hughes, Danny R; Duszak, Richard

2016-04-01

To determine recent trends related to temporal as well as national and statewide geographic variation in the U.S. radiologist and radiology resident workforce. This retrospective HIPAA-compliant study was exempted from the internal review board. Federal Area Health Resources Files and Medicare 5% research identifiable files were used to compute parameters related to the radiologist workforce. Geographic variation and annual temporal trends were analyzed. Pearson and Spearman correlations were assessed. Nationally, the number of radiology trainees increased 84.2% from a nadir in 1997 (3080 trainees) to 2011 (5674 trainees) and showed high state-to-state variation (range, 0-678 trainees in 2011). However, total radiologists nationally increased 39.2% from 1995 (27 906 radiologists) to 2011 (38 875 radiologists), and radiologists per 100 000 population nationally increased by 7.5% from 1995 (10.62%) to 2011 (11.42%), while showing high state-to-state variation (highest-to-lowest state ratio of 4.3). Radiologists' share of the overall physician workforce declined nationally by 8.8% from 1995 (4.0%) to 2011 (3.7%), with moderate state-to-state variation (highest-to-lowest state ratio of 1.7). Radiology trainee numbers exhibited weak-to-moderate positive state-by-state correlation with radiologists per 100 000 population (r = 0.292-0.532), but moderate-to-strong inverse correlation with the percentage of radiologists in rural practice (r = -0.464 to -0.635). Although the number of radiology trainees dramatically increased, radiologists per 100 000 population increased only slightly, and radiologists' share of the overall physician workforce declined. State-to-state variations in radiologist and radiology resident workforces are high, which suggests a potential role for geographic redistribution rather than changes in the overall workforce size.

Geometric Positioning Accuracy Improvement of ZY-3 Satellite Imagery Based on Statistical Learning Theory

Directory of Open Access Journals (Sweden)

Niangang Jiao

2018-05-01

Full Text Available With the increasing demand for high-resolution remote sensing images for mapping and monitoring the Earth’s environment, geometric positioning accuracy improvement plays a significant role in the image preprocessing step. Based on the statistical learning theory, we propose a new method to improve the geometric positioning accuracy without ground control points (GCPs. Multi-temporal images from the ZY-3 satellite are tested and the bias-compensated rational function model (RFM is applied as the block adjustment model in our experiment. An easy and stable weight strategy and the fast iterative shrinkage-thresholding (FIST algorithm which is widely used in the field of compressive sensing are improved and utilized to define the normal equation matrix and solve it. Then, the residual errors after traditional block adjustment are acquired and tested with the newly proposed inherent error compensation model based on statistical learning theory. The final results indicate that the geometric positioning accuracy of ZY-3 satellite imagery can be improved greatly with our proposed method.

Radiologist's exposition during the radioscopy of the digestive tract in esophagus-gastro-duodenum studies

International Nuclear Information System (INIS)

Montanez, O.; Blanco, D.

1988-01-01

The results of personal dosimetry confirm that one of the most exposed groups to the ionizing radiations is those of Radiologists who work with radioscopy of the digestive tract. However, the particular conditions of the exposition complicate the interpretation of the reading for the values obtained on the dosimeter. In order to improve such interpretation, it has done simultaneous measurements with the routine dosimeter and with thermoluminescent dosimeters (TLD) of lithium fluoride(LiF). It has selected eight places on the worker's body and located such dosimeters, so that the dose was integrated during thirty studies. It could verify that, if the dosimeter is located in agreement with the recommendations of the International Commission of Radiological Protection(ICRP), the reading overestimates in several times the dose in whole body(or effective dose). It has also considered that the amount of such procedures done by the radiologist is limited in this case, by the effective dose

Book Review: Radiology where there are no radiologists ...

African Journals Online (AJOL)

Abstract. "Radiology Where There Are no Radiologists" "Manual of Radiographic interpretation for General Practitioners" Palmer, ps., Cockshott, WP., Hegedus v., Samuel, E.: WHO Basic Radiological System WHO, Geneva, 1985 (SFr. 23) ...

Improvement of Diagnostic Accuracy by Standardization in Diuretic Renal Scan

International Nuclear Information System (INIS)

Hyun, In Young; Lee, Dong Soo; Lee, Kyung Han; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Kim, Kwang Myung; Choi, Hwang; Choi, Yong

1995-01-01

We evaluated diagnostic accuracy of diuretic renal scan with standardization in 45 children(107 hydronephrotic kidneys) with 91 diuretic assessments. Sensitivity was 100% specificity was 78%, and accuracy was 84% in 49 hydronephrotic kidneys with standardization. Diuretic renal scan without standardization, sensitivity was 100%, specificity was 38%, and accuracy was 57% in 58 hydronephrotic kidneys. The false-positive results were observed in 25 cases without standardization, and in 8 cases with standardization. In duretic renal scans without standardization, the causes of false-positive results were 10 early injection of lasix before mixing of radioactivity in loplsty, 6 extrarenal pelvis, and 3 immature kidneys of false-positive results were 2 markedly dilated systems postpyeloplsty, 2 etrarenal pevis, 1 immature kidney of neonate , and 2 severe renal dysfunction, 1 vesicoureteral, reflux. In diuretic renal scan without standardization the false-positive results by inadequate study were common, but false-positive results by inadequate study were not found after standardization. The false-positive results by dilated pelvo-calyceal systems postpyeloplsty, extrarenal pelvis, and immature kidneys of, neonates were not dissolved after standardization. In conclusion, diagnostic accuracy of diuretic renal scan with standardization was useful in children with renal outflow tract obstruction by improving specificity significantly.

Do Radiologists Want/Need Training in Cardiopulmonary Resuscitation?

International Nuclear Information System (INIS)

Schellhammer, F.

2003-01-01

Purpose: Prompt and effective cardiopulmonary resuscitation (CPR) decreases morbidity and mortality following cardiopulmonary arrest. Radiologists are frequently confronted with severely ill patients, who may deteriorate at any time. Furthermore, they have to be aware of life-threatening reactions towards contrast media. This study was designed to assess experience and self-estimation of German-speaking radiologists in CPR and cardiac defibrillation (CD). Material and Methods: 650 German-speaking radiologists were audited by a specially designed questionnaire, which was sent via e-mail. The answers were expected to be re-mailed within a 2-month period. Results: The response rate was 12.6%. 72.8% of the responders had performed at least 1 CPR (range 9.5 ± 13.1) and 37% at least 1 CD. 67.9% had had opportunities to attend training courses, which had been utilized by 41.8% of them. The last training of the responders was more than 2 years ago in 69.2% and more than 5 years ago in 37%. Of all responders 75.6% expressed the need for further education. Conclusion: The small response rate indicates the small importance of CPR in the subpopulation surveyed. The vast majority of the responders, however, showed interest in basic and advanced life support and advocated regular updates. It seems reasonable that radiological Dept. themselves should organize courses in order to cope with their specific situations

Do Radiologists Want/Need Training in Cardiopulmonary Resuscitation?

Energy Technology Data Exchange (ETDEWEB)

Schellhammer, F. [St. Katharinen Hospital, Frechen (Germany). Dept. of Radiology

2003-03-01

Purpose: Prompt and effective cardiopulmonary resuscitation (CPR) decreases morbidity and mortality following cardiopulmonary arrest. Radiologists are frequently confronted with severely ill patients, who may deteriorate at any time. Furthermore, they have to be aware of life-threatening reactions towards contrast media. This study was designed to assess experience and self-estimation of German-speaking radiologists in CPR and cardiac defibrillation (CD). Material and Methods: 650 German-speaking radiologists were audited by a specially designed questionnaire, which was sent via e-mail. The answers were expected to be re-mailed within a 2-month period. Results: The response rate was 12.6%. 72.8% of the responders had performed at least 1 CPR (range 9.5 {+-} 13.1) and 37% at least 1 CD. 67.9% had had opportunities to attend training courses, which had been utilized by 41.8% of them. The last training of the responders was more than 2 years ago in 69.2% and more than 5 years ago in 37%. Of all responders 75.6% expressed the need for further education. Conclusion: The small response rate indicates the small importance of CPR in the subpopulation surveyed. The vast majority of the responders, however, showed interest in basic and advanced life support and advocated regular updates. It seems reasonable that radiological Dept. themselves should organize courses in order to cope with their specific situations.

Improving the radiologist–CAD interaction: designing for appropriate trust

International Nuclear Information System (INIS)

Jorritsma, W.; Cnossen, F.; Ooijen, P.M.A. van

2015-01-01

Computer-aided diagnosis (CAD) has great potential to improve radiologists' diagnostic performance. However, the reported performance of the radiologist–CAD team is lower than what might be expected based on the performance of the radiologist and the CAD system in isolation. This indicates that the interaction between radiologists and the CAD system is not optimal. An important factor in the interaction between humans and automated aids (such as CAD) is trust. Suboptimal performance of the human–automation team is often caused by an inappropriate level of trust in the automation. In this review, we examine the role of trust in the radiologist–CAD interaction and suggest ways to improve the output of the CAD system so that it allows radiologists to calibrate their trust in the CAD system more effectively. Observer studies of the CAD systems show that radiologists often have an inappropriate level of trust in the CAD system. They sometimes under-trust CAD, thereby reducing its potential benefits, and sometimes over-trust it, leading to diagnostic errors they would not have made without CAD. Based on the literature on trust in human–automation interaction and the results of CAD observer studies, we have identified four ways to improve the output of CAD so that it allows radiologists to form a more appropriate level of trust in CAD. Designing CAD systems for appropriate trust is important and can improve the performance of the radiologist–CAD team. Future CAD research and development should acknowledge the importance of the radiologist–CAD interaction, and specifically the role of trust therein, in order to create the perfect artificial partner for the radiologist. This review focuses on the role of trust in the radiologist–CAD interaction. The aim of the review is to encourage CAD developers to design for appropriate trust and thereby improve the performance of the radiologist–CAD team. - Highlights: • Radiologists often have an inappropriate

Diagnostic performance of radiographers as compared to radiologists in magnetic resonance colonography

International Nuclear Information System (INIS)

Zijta, F.M.; Florie, J.; Jensch, S.; Bipat, S.; Nievelstein, R.A.J.; Poulus, M.; Thomassen-de Graaf, M.A.; Montauban van Swijndregt, A.D.; Stoker, J.

2010-01-01

Purpose: To evaluate the diagnostic performance of radiographers compared to radiologists in the detection of colorectal lesions in MR colonography. Material and methods: 159 patients at increased risk of colorectal cancer were included. Four different experienced observers, one MR radiologist, one radiologist in training and two radiographers evaluated all MR colonography examinations. The protocol included T1-weighted and T2-weighted sequences in prone and supine position. Colonoscopy was used as reference standard. Mean sensitivity rates with 95% confidence intervals (CIs) were determined on a per-patient and per-polyp basis, segmented by size (≥6 mm and ≥10 mm). Specificity was calculated on a per-patient basis. The McNemar and chi-square (χ 2 ) test was used to determine significant differences. Results: At colonoscopy 74 patients (47%) had normal findings; 23 patients had 40 polyps with a size ≥6 mm. In 10 patients at least 1 polyp ≥10 mm was found (20 polyps in total). Similar sensitivities for patients with lesions ≥10 mm were found for radiologists and radiographers (65% (95%CI: 44-86%) vs. 50% (95%CI: 28-72%)) (p = n.s.). For lesions ≥10 mm combined per-patient specificity for radiologists and radiographers was 96% (95%CI: 94-98%) and 73% (95%CI: 68-79%) (p < 0.0001). Combined per-patient sensitivity for lesions ≥6 mm differed significantly between both groups of observers (57% (95%CI: 42-71%) vs. 33% (95%CI: 19-46%)) (p = 0.03). Conclusion: Radiographers have comparable sensitivity but lower specificity relative to radiologists in the detection of colorectal lesions ≥10 mm at MR colonography. Adequate training in evaluating MR colonography is necessary, especially for readers with no prior experience with colonography.

Improving substructure identification accuracy of shear structures using virtual control system

Science.gov (United States)

Zhang, Dongyu; Yang, Yang; Wang, Tingqiang; Li, Hui

2018-02-01

Substructure identification is a powerful tool to identify the parameters of a complex structure. Previously, the authors developed an inductive substructure identification method for shear structures. The identification error analysis showed that the identification accuracy of this method is significantly influenced by the magnitudes of two key structural responses near a certain frequency; if these responses are unfavorable, the method cannot provide accurate estimation results. In this paper, a novel method is proposed to improve the substructure identification accuracy by introducing a virtual control system (VCS) into the structure. A virtual control system is a self-balanced system, which consists of some control devices and a set of self-balanced forces. The self-balanced forces counterbalance the forces that the control devices apply on the structure. The control devices are combined with the structure to form a controlled structure used to replace the original structure in the substructure identification; and the self-balance forces are treated as known external excitations to the controlled structure. By optimally tuning the VCS’s parameters, the dynamic characteristics of the controlled structure can be changed such that the original structural responses become more favorable for the substructure identification and, thus, the identification accuracy is improved. A numerical example of 6-story shear structure is utilized to verify the effectiveness of the VCS based controlled substructure identification method. Finally, shake table tests are conducted on a 3-story structural model to verify the efficacy of the VCS to enhance the identification accuracy of the structural parameters.

How social information can improve estimation accuracy in human groups.

Science.gov (United States)

Jayles, Bertrand; Kim, Hye-Rin; Escobedo, Ramón; Cezera, Stéphane; Blanchet, Adrien; Kameda, Tatsuya; Sire, Clément; Theraulaz, Guy

2017-11-21

In our digital and connected societies, the development of social networks, online shopping, and reputation systems raises the questions of how individuals use social information and how it affects their decisions. We report experiments performed in France and Japan, in which subjects could update their estimates after having received information from other subjects. We measure and model the impact of this social information at individual and collective scales. We observe and justify that, when individuals have little prior knowledge about a quantity, the distribution of the logarithm of their estimates is close to a Cauchy distribution. We find that social influence helps the group improve its properly defined collective accuracy. We quantify the improvement of the group estimation when additional controlled and reliable information is provided, unbeknownst to the subjects. We show that subjects' sensitivity to social influence permits us to define five robust behavioral traits and increases with the difference between personal and group estimates. We then use our data to build and calibrate a model of collective estimation to analyze the impact on the group performance of the quantity and quality of information received by individuals. The model quantitatively reproduces the distributions of estimates and the improvement of collective performance and accuracy observed in our experiments. Finally, our model predicts that providing a moderate amount of incorrect information to individuals can counterbalance the human cognitive bias to systematically underestimate quantities and thereby improve collective performance. Copyright © 2017 the Author(s). Published by PNAS.

Improvement of vision measurement accuracy using Zernike moment based edge location error compensation model

International Nuclear Information System (INIS)

Cui, J W; Tan, J B; Zhou, Y; Zhang, H

2007-01-01

This paper presents the Zernike moment based model developed to compensate edge location errors for further improvement of the vision measurement accuracy by compensating the slight changes resulting from sampling and establishing mathematic expressions for subpixel location of theoretical and actual edges which are either vertical to or at an angle with X-axis. Experimental results show that the proposed model can be used to achieve a vision measurement accuracy of up to 0.08 pixel while the measurement uncertainty is less than 0.36μm. It is therefore concluded that as a model which can be used to achieve a significant improvement of vision measurement accuracy, the proposed model is especially suitable for edge location of images with low contrast

Radiologist and angiographic procedures. Absorbed radiation dose

International Nuclear Information System (INIS)

Tryhus, M.; Mettler, F.A. Jr.; Kelsey, C.

1987-01-01

The radiation dose absorbed by the angiographer during angiographic procedures is of vital importance to the radiologist. Nevertheless, most articles on the subject are incomplete, and few measure gonadal dose. In this study, three TLDs were used for each of the following sites: radiologist's eyes, thyroid, gonads with and without shielding apron, and hands. The average dose during carotid angiograms was 2.6, 4.1, 0.4, 4.7, and 7.1 mrads to the eyes, thyroid, gonads with and without .5 mm of lead shielding, and hands, respectively. Average dose during abdominal and peripheral vascular angiographic procedures was 5.2, 7.5, 1.2, 8.5, and 39.9 mrads to the eyes, thyroid, gonads with and without shielding, and hands, respectively. A literature review demonstrates a significant reduction in radiation dose to the angiographer after the advent of automated injectors. Our measured doses for carotid angiography are compatible with contemporary reported values. There was poor correlation with fluoroscopy time and measured dose to the angiographer

An observer study comparing spot imaging regions selected by radiologists and a computer for an automated stereo spot mammography technique

International Nuclear Information System (INIS)

Goodsitt, Mitchell M.; Chan, Heang-Ping; Lydick, Justin T.; Gandra, Chaitanya R.; Chen, Nelson G.; Helvie, Mark A.; Bailey, Janet E.; Roubidoux, Marilyn A.; Paramagul, Chintana; Blane, Caroline E.; Sahiner, Berkman; Petrick, Nicholas A.

2004-01-01

We are developing an automated stereo spot mammography technique for improved imaging of suspicious dense regions within digital mammograms. The technique entails the acquisition of a full-field digital mammogram, automated detection of a suspicious dense region within that mammogram by a computer aided detection (CAD) program, and acquisition of a stereo pair of images with automated collimation to the suspicious region. The latter stereo spot image is obtained within seconds of the original full-field mammogram, without releasing the compression paddle. The spot image is viewed on a stereo video display. A critical element of this technique is the automated detection of suspicious regions for spot imaging. We performed an observer study to compare the suspicious regions selected by radiologists with those selected by a CAD program developed at the University of Michigan. True regions of interest (TROIs) were separately determined by one of the radiologists who reviewed the original mammograms, biopsy images, and histology results. We compared the radiologist and computer-selected regions of interest (ROIs) to the TROIs. Both the radiologists and the computer were allowed to select up to 3 regions in each of 200 images (mixture of 100 CC and 100 MLO views). We computed overlap indices (the overlap index is defined as the ratio of the area of intersection to the area of interest) to quantify the agreement between the selected regions in each image. The averages of the largest overlap indices per image for the 5 radiologist-to-computer comparisons were directly related to the average number of regions per image traced by the radiologists (about 50% for 1 region/image, 84% for 2 regions/image and 96% for 3 regions/image). The average of the overlap indices with all of the TROIs was 73% for CAD and 76.8%+/-10.0% for the radiologists. This study indicates that the CAD determined ROIs could potentially be useful for a screening technique that includes stereo spot

The relationship between back pain and lead apron use in radiologists

Energy Technology Data Exchange (ETDEWEB)

Moore, B.; vanSonnenberg, E.; Casola, G.; Novelline, R.A. (Department of Radiology, University of California, San Diego (Unites States))

1992-01-01

Anecdotal experience has suggested that back pain in radiologists may result from extensive wearing of lead aprons. To investigate this possibility, the authors sent questionnaires to 688 radiologists in various subspecialties whose use of lead aprons varied from none to moderate to extensive. The questionnaire included both objective items that quantitated apron use and back pain and subjective items that asked, for example, if the respondent believed that lead aprons were responsible for his or her back pain. They received 236 responses (34% response rate). Objective data from those radiologists who had experienced no back pain before wearing a lead apron (179 radiologists, 26% of those surveyed) were tabulated; respondents were grouped according to age, time spent wearing a lead apron, and degree of back pain. Odds ratios were calculated. Answers to subjective questions for all respondents were tabulated. Back pain was reported by 52% of those who estimated their lead apron use at greater than or equal to 10 hr per week, the mean response, as opposed to 46% of those who wore lead aprons fewer than 10 hr a week. These and related results were not statistically significant. Our study does not prove that wearing a lead apron is a significant risk factor for the development of back pain.

The relationship between back pain and lead apron use in radiologists

International Nuclear Information System (INIS)

Moore, B.; vanSonnenberg, E.; Casola, G.; Novelline, R.A.

1992-01-01

Anecdotal experience has suggested that back pain in radiologists may result from extensive wearing of lead aprons. To investigate this possibility, the authors sent questionnaires to 688 radiologists in various subspecialties whose use of lead aprons varied from none to moderate to extensive. The questionnaire included both objective items that quantitated apron use and back pain and subjective items that asked, for example, if the respondent believed that lead aprons were responsible for his or her back pain. They received 236 responses (34% response rate). Objective data from those radiologists who had experienced no back pain before wearing a lead apron (179 radiologists, 26% of those surveyed) were tabulated; respondents were grouped according to age, time spent wearing a lead apron, and degree of back pain. Odds ratios were calculated. Answers to subjective questions for all respondents were tabulated. Back pain was reported by 52% of those who estimated their lead apron use at greater than or equal to 10 hr per week, the mean response, as opposed to 46% of those who wore lead aprons fewer than 10 hr a week. These and related results were not statistically significant. Our study does not prove that wearing a lead apron is a significant risk factor for the development of back pain

Expanding the use of Microsoft PowerPoint. An overview for radiologists

International Nuclear Information System (INIS)

Scarsbrook, A.F.; Graham, R.N.J.; Perriss, R.W.

2006-01-01

Most radiologists need to give a lecture, present research or speak at a scientific meeting at some stage in their career. In our technologically advanced world, electronic presentations have become the norm and are almost universally expected. Microsoft PowerPoint is by far and away the most commonly used computer-based presentation package. As a result most radiologists have developed at least a modicum of PowerPoint expertise but many lack the time or inclination to develop these skills further. The purpose of this article is to explain how to expand the use of PowerPoint with freely available resources from the internet, to highlight websites where useful information on advanced PowerPoint techniques can be found, and to discuss extended functions of PowerPoint likely to be of interest to radiologists such as poster design

Evaluation of scanning 2D barcoded vaccines to improve data accuracy of vaccines administered.

Science.gov (United States)

Daily, Ashley; Kennedy, Erin D; Fierro, Leslie A; Reed, Jenica Huddleston; Greene, Michael; Williams, Warren W; Evanson, Heather V; Cox, Regina; Koeppl, Patrick; Gerlach, Ken

2016-11-11

Accurately recording vaccine lot number, expiration date, and product identifiers, in patient records is an important step in improving supply chain management and patient safety in the event of a recall. These data are being encoded on two-dimensional (2D) barcodes on most vaccine vials and syringes. Using electronic vaccine administration records, we evaluated the accuracy of lot number and expiration date entered using 2D barcode scanning compared to traditional manual or drop-down list entry methods. We analyzed 128,573 electronic records of vaccines administered at 32 facilities. We compared the accuracy of records entered using 2D barcode scanning with those entered using traditional methods using chi-square tests and multilevel logistic regression. When 2D barcodes were scanned, lot number data accuracy was 1.8 percentage points higher (94.3-96.1%, Pmanufacturer, month vaccine was administered, and vaccine type were associated with variation in accuracy for both lot number and expiration date. Two-dimensional barcode scanning shows promise for improving data accuracy of vaccine lot number and expiration date records. Adapting systems to further integrate with 2D barcoding could help increase adoption of 2D barcode scanning technology. Published by Elsevier Ltd.

The 'Battered-Child-Syndrome': The view of the pediatric radiologist

International Nuclear Information System (INIS)

Greinacher, I.; Troeger, J.

1982-01-01

The diagnosis of the Battered-Child-Syndrome (BSC) is made by the pediatrician and the radiologist. The recognition of this entity by the radiologist is possible because of the high frequency of the typical skeletal lesions. This skeletal changes are illustrated by X-ray pictures and bone scans. Not only skeletal trauma can be discovered but also visceral injuries may be combined and diagnosed in the BCS. For the detection of all changes in the BCS nowadays all possible imaging procedures should be used. Some forensic problems in this field are added. (orig.)

Algorithms and parameters for improved accuracy in physics data libraries

International Nuclear Information System (INIS)

Batič, M; Hoff, G; Pia, M G; Saracco, P; Han, M; Kim, C H; Hauf, S; Kuster, M; Seo, H

2012-01-01

Recent efforts for the improvement of the accuracy of physics data libraries used in particle transport are summarized. Results are reported about a large scale validation analysis of atomic parameters used by major Monte Carlo systems (Geant4, EGS, MCNP, Penelope etc.); their contribution to the accuracy of simulation observables is documented. The results of this study motivated the development of a new atomic data management software package, which optimizes the provision of state-of-the-art atomic parameters to physics models. The effect of atomic parameters on the simulation of radioactive decay is illustrated. Ideas and methods to deal with physics models applicable to different energy ranges in the production of data libraries, rather than at runtime, are discussed.

Automated registration of diagnostic to prediagnostic x-ray mammograms: Evaluation and comparison to radiologists' accuracy

Energy Technology Data Exchange (ETDEWEB)

Pinto Pereira, Snehal M.; Hipwell, John H.; McCormack, Valerie A.; Tanner, Christine; Moss, Sue M.; Wilkinson, Louise S.; Khoo, Lisanne A. L.; Pagliari, Catriona; Skippage, Pippa L.; Kliger, Carole J.; Hawkes, David J.; Santos Silva, Isabel M. dos [Cancer Research UK Epidemiology and Genetics Group, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom); Centre for Medical Image Computing, University College London, London WC1E 6BT (United Kingdom); Lifestyle and Cancer Group, International Agency for Research on Cancer, 150 cours Albert Thomas, Lyon 69008 (France); Centre for Medical Image Computing, University College London, London WC1E 6BT (United Kingdom); Cancer Screening Evaluation Unit, Institute of Cancer Research, Surrey SM2 5NG (United Kingdom); St. George' s Healthcare NHS Trust and South West London Breast Screening Service, London SW17 0QT (United Kingdom); Centre for Medical Image Computing, University College London, London WC1E 6BT (United Kingdom); Cancer Research UK Epidemiology and Genetics Group, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT (United Kingdom)

2010-09-15

Purpose: To compare and evaluate intensity-based registration methods for computation of serial x-ray mammogram correspondence. Methods: X-ray mammograms were simulated from MRIs of 20 women using finite element methods for modeling breast compressions and employing a MRI/x-ray appearance change model. The parameter configurations of three registration methods, affine, fluid, and free-form deformation (FFD), were optimized for registering x-ray mammograms on these simulated images. Five mammography film readers independently identified landmarks (tumor, nipple, and usually two other normal features) on pairs of diagnostic and corresponding prediagnostic digitized images from 52 breast cancer cases. Landmarks were independently reidentified by each reader. Target registration errors were calculated to compare the three registration methods using the reader landmarks as a gold standard. Data were analyzed using multilevel methods. Results: Between-reader variability varied with landmark (p<0.01) and screen (p=0.03), with between-reader mean distance (mm) in point location on the diagnostic/prediagnostic images of 2.50 (95% CI 1.95, 3.15)/2.84 (2.24, 3.55) for nipples and 4.26 (3.43, 5.24)/4.76 (3.85, 5.84) for tumors. Registration accuracy was sensitive to the type of landmark and the amount of breast density. For dense breasts ({>=}40%), the affine and fluid methods outperformed FFD. For breasts with lower density, the affine registration surpassed both fluid and FFD. Mean accuracy (mm) of the affine registration varied between 3.16 (95% CI 2.56, 3.90) for nipple points in breasts with density 20%-39% and 5.73 (4.80, 6.84) for tumor points in breasts with density <20%. Conclusions: Affine registration accuracy was comparable to that between independent film readers. More advanced two-dimensional nonrigid registration algorithms were incapable of increasing the accuracy of image alignment when compared to affine registration.

Accuracy Improvement Capability of Advanced Projectile Based on Course Correction Fuze Concept

Directory of Open Access Journals (Sweden)

Ahmed Elsaadany

2014-01-01

Full Text Available Improvement in terminal accuracy is an important objective for future artillery projectiles. Generally it is often associated with range extension. Various concepts and modifications are proposed to correct the range and drift of artillery projectile like course correction fuze. The course correction fuze concepts could provide an attractive and cost-effective solution for munitions accuracy improvement. In this paper, the trajectory correction has been obtained using two kinds of course correction modules, one is devoted to range correction (drag ring brake and the second is devoted to drift correction (canard based-correction fuze. The course correction modules have been characterized by aerodynamic computations and flight dynamic investigations in order to analyze the effects on deflection of the projectile aerodynamic parameters. The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved. The drag ring brake is found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in large range correction. The correction occasion time can be predefined depending on required correction of range. On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate. In addition, the canard extension induces a high-frequency incidence angle as canards reciprocate at the roll motion.

Accuracy improvement capability of advanced projectile based on course correction fuze concept.

Science.gov (United States)

Elsaadany, Ahmed; Wen-jun, Yi

2014-01-01

Improvement in terminal accuracy is an important objective for future artillery projectiles. Generally it is often associated with range extension. Various concepts and modifications are proposed to correct the range and drift of artillery projectile like course correction fuze. The course correction fuze concepts could provide an attractive and cost-effective solution for munitions accuracy improvement. In this paper, the trajectory correction has been obtained using two kinds of course correction modules, one is devoted to range correction (drag ring brake) and the second is devoted to drift correction (canard based-correction fuze). The course correction modules have been characterized by aerodynamic computations and flight dynamic investigations in order to analyze the effects on deflection of the projectile aerodynamic parameters. The simulation results show that the impact accuracy of a conventional projectile using these course correction modules can be improved. The drag ring brake is found to be highly capable for range correction. The deploying of the drag brake in early stage of trajectory results in large range correction. The correction occasion time can be predefined depending on required correction of range. On the other hand, the canard based-correction fuze is found to have a higher effect on the projectile drift by modifying its roll rate. In addition, the canard extension induces a high-frequency incidence angle as canards reciprocate at the roll motion.

The accuracy of chest radiographs in the detection of congenital heart disease and in the diagnosis of specific congenital cardiac lesions

International Nuclear Information System (INIS)

Laya, Bernard F.; Goske, Marilyn J.; Morrison, Stuart; Reid, Janet R.; Swischuck, Leonard; Ey, Elizabeth H.; Murphy, Daniel J.; Lieber, Michael; Obuchowski, Nancy

2006-01-01

Congenital heart disease (CHD) is a significant cause of morbidity and mortality in pediatric patients. Traditional teaching holds that specific types of CHD can be diagnosed on the chest radiograph (CXR) through pattern recognition. To determine the accuracy of radiologists in detecting CHD on the CXR. This study was a blinded retrospective review of chest radiographs from 281 patients (<12 years) by five pediatric radiologists from three institutions. Thirteen groups were evaluated that included 12 categories of CHD and a control group of patients without heart disease. Radiographs were assessed for heart size, heart and mediastinal shape and vascularity. Clinical information, angiography, echocardiograms and surgery were used as the gold standard for definitive diagnosis. The average accuracy of the five readers in distinguishing normal from CHD patients was 78% (range of 72% to 82%). The overall measure of accuracy in distinguishing specific congenital cardiac lesions among 13 groups of patients was 71% (range of 63% to 79%). CXR alone is not diagnostic of specific cardiac lesions, with a low accuracy of only 71%. We believe that less emphasis should be placed on the use of radiographs alone in diagnosing specific congenital cardiac lesions. (orig.)

Deciding why and when to use CT in children: a radiologist's perspective

Energy Technology Data Exchange (ETDEWEB)

Frush, Donald P. [1905 McGovern-Davison Children' s Health Center, Duke University Medical Center, Departments of Radiology and Pediatrics, Durham, NC (United States)

2014-10-15

Defining what is appropriate or inappropriate with respect to CT scanning is challenging. There are a variety of influences on scan utilization in children, some more widely recognized and acknowledged than others. It is important to understand the contribution of these elements as we move toward improved utilization. This must be through partnerships and shared efforts and accountability. These efforts include improved resources such as consensus appropriateness criteria and guidelines including decision rules and support. But there also need to be trench-based strategies on the part of practicing radiologists to model cooperative behavior rather than blame-centered behavior. (orig.)

Improving the Accuracy of Cloud Detection Using Machine Learning

Science.gov (United States)

Craddock, M. E.; Alliss, R. J.; Mason, M.

2017-12-01

show 97% accuracy during the daytime, 94% accuracy at night, and 95% accuracy for all times. The total time to train, tune and test was approximately one week. The improved performance and reduced time to produce results is testament to improved computer technology and the use of machine learning as a more efficient and accurate methodology of cloud detection.

MDCT arthrography of the wrist: Diagnostic accuracy and indications

International Nuclear Information System (INIS)

De Filippo, Massimo; Pogliacomi, Francesco; Bertellini, Annalisa; Araoz, Philip A.; Averna, Raffaele; Sverzellati, Nicola; Ingegnoli, Anna; Corradi, Maurizio; Costantino, Cosimo; Zompatori, Maurizio

2010-01-01

Purpose: To evaluate the diagnostic accuracy and indications of arthrography with Multidetector Computed Tomography (arthro-MDCT) of the wrist in patients with absolute or relative contraindications to magnetic resonance imaging (MRI) studies and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and methods: After intra-articular injection of iodixanol and volumetric acquisition, 43 wrists in patients of both genders (18 females, 25 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. Fifteen patients had prior wrist surgery. The patients had arthralgia, degenerative and traumatic arthropathies as well as limited range of motion, but no radiologically detected fractures. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In non-operated and operated wrists the comparison between arthro-MDCT and arthroscopy showed sensitivity, specificity and accuracy ranging between 92% and 94% for triangular fibrocartilage complex (TFCC), between 80% and 100% for intrinsic ligaments located within the proximal carpal compartment, and between 94% and 100% for articular cartilage. Inter-observer agreement between two radiologists, in the evaluation of all types of lesions, was almost perfect (k = 0.96) and statistically significant (p < 0.05). Conclusions: Arthro-MDCT of the wrist provides an accurate diagnosis to identify chondral, fibrocartilaginous and intra-articular ligament lesions in patients who cannot be evaluated by MRI, and in post-surgical patients.

MDCT arthrography of the wrist: Diagnostic accuracy and indications

Energy Technology Data Exchange (ETDEWEB)

De Filippo, Massimo [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy)], E-mail: massimo.defilippo@unipr.it; Pogliacomi, Francesco [Orthopaedics, Traumatology and Functional Rehabilitation Unit, Department of Surgical Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Bertellini, Annalisa [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy); Araoz, Philip A. [Department of Radiology, Division of Biostatistics, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (United States); Averna, Raffaele; Sverzellati, Nicola; Ingegnoli, Anna [Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsci, 14, 43100 Parma (Italy); Corradi, Maurizio; Costantino, Cosimo [Orthopaedics, Traumatology and Functional Rehabilitation Unit, Department of Surgical Sciences, University of Parma, Parma Hospital, Via Gramsci 14, 43100 Parma (Italy); Zompatori, Maurizio [Department of Radiological and Histopathological Sciences, Policlinic S.Orsola-Malpighi, University of Bologna, Via Massarenti 9, 40138 Bologna (Italy)

2010-04-15

Purpose: To evaluate the diagnostic accuracy and indications of arthrography with Multidetector Computed Tomography (arthro-MDCT) of the wrist in patients with absolute or relative contraindications to magnetic resonance imaging (MRI) studies and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and methods: After intra-articular injection of iodixanol and volumetric acquisition, 43 wrists in patients of both genders (18 females, 25 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. Fifteen patients had prior wrist surgery. The patients had arthralgia, degenerative and traumatic arthropathies as well as limited range of motion, but no radiologically detected fractures. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In non-operated and operated wrists the comparison between arthro-MDCT and arthroscopy showed sensitivity, specificity and accuracy ranging between 92% and 94% for triangular fibrocartilage complex (TFCC), between 80% and 100% for intrinsic ligaments located within the proximal carpal compartment, and between 94% and 100% for articular cartilage. Inter-observer agreement between two radiologists, in the evaluation of all types of lesions, was almost perfect (k = 0.96) and statistically significant (p < 0.05). Conclusions: Arthro-MDCT of the wrist provides an accurate diagnosis to identify chondral, fibrocartilaginous and intra-articular ligament lesions in patients who cannot be evaluated by MRI, and in post-surgical patients.

Method for Improving Indoor Positioning Accuracy Using Extended Kalman Filter

Directory of Open Access Journals (Sweden)

Seoung-Hyeon Lee

2016-01-01

Full Text Available Beacons using bluetooth low-energy (BLE technology have emerged as a new paradigm of indoor positioning service (IPS because of their advantages such as low power consumption, miniaturization, wide signal range, and low cost. However, the beacon performance is poor in terms of the indoor positioning accuracy because of noise, motion, and fading, all of which are characteristics of a bluetooth signal and depend on the installation location. Therefore, it is necessary to improve the accuracy of beacon-based indoor positioning technology by fusing it with existing indoor positioning technology, which uses Wi-Fi, ZigBee, and so forth. This study proposes a beacon-based indoor positioning method using an extended Kalman filter that recursively processes input data including noise. After defining the movement of a smartphone on a flat two-dimensional surface, it was assumed that the beacon signal is nonlinear. Then, the standard deviation and properties of the beacon signal were analyzed. According to the analysis results, an extended Kalman filter was designed and the accuracy of the smartphone’s indoor position was analyzed through simulations and tests. The proposed technique achieved good indoor positioning accuracy, with errors of 0.26 m and 0.28 m from the average x- and y-coordinates, respectively, based solely on the beacon signal.

Inborn errors of metabolism for the diagnostic radiologist

Energy Technology Data Exchange (ETDEWEB)

Hendriksz, Chris J. [Birmingham Children' s Hospital NHS Foundation Trust, Department of Clinical Inherited Metabolic Disorders, Birmingham (United Kingdom)

2009-03-15

Inherited metabolic disorders are becoming more important with the increasing availability of diagnostic methods and therapies for these conditions. The radiologist has become an important link in making the diagnosis or collaborating with the specialist centre to diagnose these disorders and monitor effects of therapy. The modes of presentation, disease-specific groups, classic radiological features and investigations are explored in this article to try and give the general radiologist some crucial background knowledge. The following presentations are covered: acute intoxication, hypoglycaemia, developmental delay and storage features. Specific groups of disorders covered are the abnormalities of intermediary metabolism, disorders of fatty acid oxidation and ketogenesis, mitochondrial disorders, lysosomal storage disorders, and, briefly, other groups such as peroxisomal disorders, disorders of glycosylation, and creatine synthesis disorders. New advances and the demands for monitoring are also briefly explored. (orig.)

Inborn errors of metabolism for the diagnostic radiologist

International Nuclear Information System (INIS)

Hendriksz, Chris J.

2009-01-01

Inherited metabolic disorders are becoming more important with the increasing availability of diagnostic methods and therapies for these conditions. The radiologist has become an important link in making the diagnosis or collaborating with the specialist centre to diagnose these disorders and monitor effects of therapy. The modes of presentation, disease-specific groups, classic radiological features and investigations are explored in this article to try and give the general radiologist some crucial background knowledge. The following presentations are covered: acute intoxication, hypoglycaemia, developmental delay and storage features. Specific groups of disorders covered are the abnormalities of intermediary metabolism, disorders of fatty acid oxidation and ketogenesis, mitochondrial disorders, lysosomal storage disorders, and, briefly, other groups such as peroxisomal disorders, disorders of glycosylation, and creatine synthesis disorders. New advances and the demands for monitoring are also briefly explored. (orig.)

Improving the accuracy of protein secondary structure prediction using structural alignment

Directory of Open Access Journals (Sweden)

Gallin Warren J

2006-06-01

Full Text Available Abstract Background The accuracy of protein secondary structure prediction has steadily improved over the past 30 years. Now many secondary structure prediction methods routinely achieve an accuracy (Q3 of about 75%. We believe this accuracy could be further improved by including structure (as opposed to sequence database comparisons as part of the prediction process. Indeed, given the large size of the Protein Data Bank (>35,000 sequences, the probability of a newly identified sequence having a structural homologue is actually quite high. Results We have developed a method that performs structure-based sequence alignments as part of the secondary structure prediction process. By mapping the structure of a known homologue (sequence ID >25% onto the query protein's sequence, it is possible to predict at least a portion of that query protein's secondary structure. By integrating this structural alignment approach with conventional (sequence-based secondary structure methods and then combining it with a "jury-of-experts" system to generate a consensus result, it is possible to attain very high prediction accuracy. Using a sequence-unique test set of 1644 proteins from EVA, this new method achieves an average Q3 score of 81.3%. Extensive testing indicates this is approximately 4–5% better than any other method currently available. Assessments using non sequence-unique test sets (typical of those used in proteome annotation or structural genomics indicate that this new method can achieve a Q3 score approaching 88%. Conclusion By using both sequence and structure databases and by exploiting the latest techniques in machine learning it is possible to routinely predict protein secondary structure with an accuracy well above 80%. A program and web server, called PROTEUS, that performs these secondary structure predictions is accessible at http://wishart.biology.ualberta.ca/proteus. For high throughput or batch sequence analyses, the PROTEUS programs

Job satisfaction, income, workload, workplace, and demographics of Japanese radiologists in the 2008 survey

International Nuclear Information System (INIS)

Sone, Miyuki; Mizunuma, Kimiyoshi; Nakajima, Yasuo; Yasunaga, Hideo; Ohtomo, Kuni

2013-01-01

This study aimed to verify radiologists' demographics and job satisfaction in Japan and analyze factors affecting job satisfaction. A self-administered questionnaire was mailed to 7,491 eligible radiologists between April and June 2008. The questionnaire consisted of items concerning participants' demographics and job satisfaction. A multivariate regression analysis was conducted to analyze the impact of practice environments on radiologists' overall job satisfaction. There were 3,986 (53%) valid responses. In 2008, 67.7% of radiologists reported being extremely or somewhat satisfied with their job. With regard to changes in job satisfaction over the previous 5 years, 45.8% felt much increased or somewhat increased satisfaction, whereas 18.8% felt somewhat decreased or much decreased. The significant factors associated with overall job satisfaction were annual income (p<0.01) and working at larger hospitals (500 or more beds) (p<0.01). Older age (p<0.01) and night duty (p<0.01) was significantly related to dissatisfaction. The main reasons for increasing job satisfaction over 5 years were interest and lifestyle, whereas the strongest reason for decreasing job satisfaction was workload. This survey revealed Japanese radiologists had a high level of job satisfaction. (author)

Inferior Vena Cava Filter Placement and Retrieval Rates among Radiologists and Nonradiologists.

Science.gov (United States)

Guez, David; Hansberry, David R; Eschelman, David J; Gonsalves, Carin F; Parker, Laurence; Rao, Vijay M; Levin, David C

2018-04-01

To evaluate inferior vena cava (IVC) filter placement and retrieval rates among radiologists, vascular surgeons, cardiologists, other surgeons, and all other health care providers for Medicare fee-for-service beneficiaries in the years 2012-2015. The nationwide Medicare Physician/Supplier Procedure Summary Master Files were used to determine the volume and utilization rate of IVC filter placement, IVC filter repositioning, and IVC filter retrieval, which correspond to procedure codes 37191, 37192, and 37193, respectively. Procedural code 37193 was not available before 2012, so data were reviewed for the years 2012-2015. The total volume of Medicare IVC filter placement decreased from 57,785 in 2012 to 44,378 in 2015, with radiologists responsible for 60% of all filter placements. Volume of IVC filter placement declined across all specialties, including radiologists, who placed 33,744 in 2012 and 27,957 in 2015. In contrast, total retrieval of IVC filters increased from 4,060 removals in 2012 to 6,166 in 2015. Retrieval rate per 100,000 Medicare beneficiaries increased from 11 in 2012 to 16 in 2015. Radiologists removed the bulk of the filters: 64% in both 2012 and 2015. Vascular surgeons, cardiologists, and other surgeons retrieved, respectively, 20%, 10%, and 5% of all IVC filters in 2012 and 22%, 9%, and 5% in 2015. From 2012 to 2015, IVC filter placement steadily decreased across all specialties. Retrieval rate of IVC filters continued to rise over the same period. Radiologists were responsible for the majority of IVC filter placements and retrievals. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

Why radiologists lose their hospital contracts: is your contract secure?

Science.gov (United States)

Muroff, Lawrence R

2010-03-01

Previously, a hospital contract meant tenure for the incumbent group of radiologists; however, those days are long gone. Exclusive contracts have morphed into exclusive contracts with carve-outs. Turf erosion has become a fact of life for radiology practices. Now radiologists are losing their hospital contracts in record numbers. Group size, though helpful for a variety of reasons, does not ensure that a practice will be secure in its hospital setting. The reasons that groups lose their hospital contracts are varied, and in this paper, the author discusses the most common ones. Suggestions to help practices avoid this unfortunate fate are presented.

Cochlear implant: what the radiologist should know; Implante coclear: o que o radiologista precisa saber

Energy Technology Data Exchange (ETDEWEB)

Gomes, Natalia Delage; Couto, Caroline Laurita Batista; Gaiotti, Juliana Oggioni; Costa, Ana Maria Doffemond; Ribeiro, Marcelo Almeida; Diniz, Renata Lopes Furletti Caldeira, E-mail: nataliadelagegomes@gmail.com [Hospital Mater Dei, Belo Horizonte, MG (Brazil). Unidade de Radiologia e Diagnostico por Imagem

2013-05-15

Cochlear implant is the method of choice in the treatment of deep sensorineural hypoacusis, particularly in patients where conventional amplification devices do not imply noticeable clinical improvement. Imaging findings are crucial in the indication or contraindication for such surgical procedure. In the assessment of the temporal bone, radiologists should be familiar with relative or absolute contraindication factors, as well as with factors that might significantly complicate the implantation. Some criteria such as cochlear nerve aplasia, labyrinthine and/or cochlear aplasia are still considered as absolute contraindications, in spite of studies bringing such criteria into question. Cochlear dysplasias constitute relative contraindications, among them labyrinthitis ossificans is highlighted. Other alterations may be mentioned as complicating agents in the temporal bone assessment, namely, hypoplasia of the mastoid process, aberrant facial nerve, otomastoiditis, otosclerosis, dehiscent jugular bulb, enlarged endolymphatic duct and sac. The experienced radiologist assumes an important role in the evaluation of this condition. (author)

Malpractice suits in chest radiology: an evaluation of the histories of 8265 radiologists.

Science.gov (United States)

Baker, Stephen R; Patel, Ronak H; Yang, Lily; Lelkes, Valdis M; Castro, Alejandro

2013-11-01

The aim of this study was to present rates of claims, causes of error, percentage of cases resulting in a judgment, and average payments made by radiologists in chest-related malpractice cases in a survey of 8265 radiologists. The malpractice histories of 8265 radiologists were evaluated from the credentialing files of One-Call Medical Inc., a preferred provider organization for computed tomography/magnetic resonance imaging in workers' compensation cases. Of the 8265 radiologists, 2680 (32.4%) had at least 1 malpractice suit. Of those who were sued, the rate of claims was 55.1 per 1000 person years. The rate of thorax-related suits was 6.6 claims per 1000 radiology practice years (95% confidence interval, 6.0-7.2). There were 496 suits encompassing 48 different causes. Errors in diagnosis comprised 78.0% of the causes. Failure to diagnose lung cancer was by far the most frequent diagnostic error, representing 211 cases or 42.5%. Of the 496 cases, an outcome was known in 417. Sixty-one percent of these were settled in favor of the plaintiff, with a mean payment of $277,230 (95% confidence interval, 226,967-338,614). Errors in diagnosis, and among them failure to diagnose lung cancer, were by far the most common reasons for initiating a malpractice suit against radiologists related to the thorax and its contents.

Identification of Nasal Bone Fractures on Conventional Radiography and Facial CT: Comparison of the Diagnostic Accuracy in Different Imaging Modalities and Analysis of Interobserver Reliability

International Nuclear Information System (INIS)

Baek, Hye Jin; Kim, Dong Wook; Ryu, Ji Hwa; Lee, Yoo Jin

2013-01-01

There has been no study to compare the diagnostic accuracy of an experienced radiologist with a trainee in nasal bone fracture. To compare the diagnostic accuracy between conventional radiography and computed tomography (CT) for the identification of nasal bone fractures and to evaluate the interobserver reliability between a staff radiologist and a trainee. A total of 108 patients who underwent conventional radiography and CT after acute nasal trauma were included in this retrospective study. Two readers, a staff radiologist and a second-year resident, independently assessed the results of the imaging studies. Of the 108 patients, the presence of a nasal bone fracture was confirmed in 88 (81.5%) patients. The number of non-depressed fractures was higher than the number of depressed fractures. In nine (10.2%) patients, nasal bone fractures were only identified on conventional radiography, including three depressed and six non-depressed fractures. CT was more accurate as compared to conventional radiography for the identification of nasal bone fractures as determined by both readers (P <0.05), all diagnostic indices of an experienced radiologist were similar to or higher than those of a trainee, and κ statistics showed moderate agreement between the two diagnostic tools for both readers. There was no statistical difference in the assessment of interobserver reliability for both imaging modalities in the identification of nasal bone fractures. For the identification of nasal bone fractures, CT was significantly superior to conventional radiography. Although a staff radiologist showed better values in the identification of nasal bone fracture and differentiation between depressed and non-depressed fractures than a trainee, there was no statistically significant difference in the interpretation of conventional radiography and CT between a radiologist and a trainee

Improving the accuracy of livestock distribution estimates through spatial interpolation.

Science.gov (United States)

Bryssinckx, Ward; Ducheyne, Els; Muhwezi, Bernard; Godfrey, Sunday; Mintiens, Koen; Leirs, Herwig; Hendrickx, Guy

2012-11-01

Animal distribution maps serve many purposes such as estimating transmission risk of zoonotic pathogens to both animals and humans. The reliability and usability of such maps is highly dependent on the quality of the input data. However, decisions on how to perform livestock surveys are often based on previous work without considering possible consequences. A better understanding of the impact of using different sample designs and processing steps on the accuracy of livestock distribution estimates was acquired through iterative experiments using detailed survey. The importance of sample size, sample design and aggregation is demonstrated and spatial interpolation is presented as a potential way to improve cattle number estimates. As expected, results show that an increasing sample size increased the precision of cattle number estimates but these improvements were mainly seen when the initial sample size was relatively low (e.g. a median relative error decrease of 0.04% per sampled parish for sample sizes below 500 parishes). For higher sample sizes, the added value of further increasing the number of samples declined rapidly (e.g. a median relative error decrease of 0.01% per sampled parish for sample sizes above 500 parishes. When a two-stage stratified sample design was applied to yield more evenly distributed samples, accuracy levels were higher for low sample densities and stabilised at lower sample sizes compared to one-stage stratified sampling. Aggregating the resulting cattle number estimates yielded significantly more accurate results because of averaging under- and over-estimates (e.g. when aggregating cattle number estimates from subcounty to district level, P interpolation to fill in missing values in non-sampled areas, accuracy is improved remarkably. This counts especially for low sample sizes and spatially even distributed samples (e.g. P <0.001 for a sample of 170 parishes using one-stage stratified sampling and aggregation on district level

Imaging Findings in Elder Abuse: A Role for Radiologists in Detection.

Science.gov (United States)

Wong, Natalie Z; Rosen, Tony; Sanchez, Allen M; Bloemen, Elizabeth M; Mennitt, Kevin W; Hentel, Keith; Nicola, Refky; Murphy, Kieran J; LoFaso, Veronica M; Flomenbaum, Neal E; Lachs, Mark S

2017-02-01

Emergency department assessment represents a critical but often missed opportunity to identify elder abuse, which is common and has serious consequences. Among emergency care providers, diagnostic radiologists are optimally positioned to raise suspicion for mistreatment when reviewing imaging of geriatric injury victims. However, little literature exists describing relevant injury patterns, and most radiologists currently receive neither formal nor informal training in elder abuse identification. We present 2 cases to begin characterisation of the radiographic findings in elder abuse. Findings from these cases demonstrate similarities to suspicious findings in child abuse including high-energy fractures that are inconsistent with reported mechanisms and the coexistence of acute and chronic injuries. Specific injuries uncommon to accidental injury are also noted, including a distal ulnar diaphyseal fracture. We hope to raise awareness of elder abuse among diagnostic radiologists to encourage future large-scale research, increased focus on chronic osseous findings, and the addition of elder abuse to differential diagnoses. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Improving the accuracy of admitted subacute clinical costing: an action research approach.

Science.gov (United States)

Hakkennes, Sharon; Arblaster, Ross; Lim, Kim

2017-08-01

Objective The aim of the present study was to determine whether action research could be used to improve the breadth and accuracy of clinical costing data in an admitted subacute setting Methods The setting was a 100-bed in-patient rehabilitation centre. Using a pre-post study design all admitted subacute separations during the 2011-12 financial year were eligible for inclusion. An action research framework aimed at improving clinical costing methodology was developed and implemented. Results In all, 1499 separations were included in the study. A medical record audit of a random selection of 80 separations demonstrated that the use of an action research framework was effective in improving the breadth and accuracy of the costing data. This was evidenced by a significant increase in the average number of activities costed, a reduction in the average number of activities incorrectly costed and a reduction in the average number of activities missing from the costing, per episode of care. Conclusions Engaging clinicians and cost centre managers was effective in facilitating the development of robust clinical costing data in an admitted subacute setting. Further investigation into the value of this approach across other care types and healthcare services is warranted. What is known about this topic? Accurate clinical costing data is essential for informing price models used in activity-based funding. In Australia, there is currently a lack of robust admitted subacute cost data to inform the price model for this care type. What does this paper add? The action research framework presented in this study was effective in improving the breadth and accuracy of clinical costing data in an admitted subacute setting. What are the implications for practitioners? To improve clinical costing practices, health services should consider engaging key stakeholders, including clinicians and cost centre managers, in reviewing clinical costing methodology. Robust clinical costing data has

Deep Learning: A Primer for Radiologists.

Science.gov (United States)

Chartrand, Gabriel; Cheng, Phillip M; Vorontsov, Eugene; Drozdzal, Michal; Turcotte, Simon; Pal, Christopher J; Kadoury, Samuel; Tang, An

2017-01-01

Deep learning is a class of machine learning methods that are gaining success and attracting interest in many domains, including computer vision, speech recognition, natural language processing, and playing games. Deep learning methods produce a mapping from raw inputs to desired outputs (eg, image classes). Unlike traditional machine learning methods, which require hand-engineered feature extraction from inputs, deep learning methods learn these features directly from data. With the advent of large datasets and increased computing power, these methods can produce models with exceptional performance. These models are multilayer artificial neural networks, loosely inspired by biologic neural systems. Weighted connections between nodes (neurons) in the network are iteratively adjusted based on example pairs of inputs and target outputs by back-propagating a corrective error signal through the network. For computer vision tasks, convolutional neural networks (CNNs) have proven to be effective. Recently, several clinical applications of CNNs have been proposed and studied in radiology for classification, detection, and segmentation tasks. This article reviews the key concepts of deep learning for clinical radiologists, discusses technical requirements, describes emerging applications in clinical radiology, and outlines limitations and future directions in this field. Radiologists should become familiar with the principles and potential applications of deep learning in medical imaging. © RSNA, 2017.

Evaluation of the Occupational Doses of Interventional Radiologists

International Nuclear Information System (INIS)

Kuipers, Gerritjan; Velders, Xandra L.; Winter, Robbert J. de; Reekers, Jim A.; Piek, Jan J.

2008-01-01

The aim of the present study was to determine whether there is a linear relation between the doses measured above and those measured under the lead apron of the radiologists performing interventional procedures. To monitor radiation exposure the International Commission of Radiological Protection (ICRP) recommends the use of a single dosimeter under the protective apron. To determine the exposure more accurately an additional dosimeter is recommended above the protective apron. The exposure of eight radiologists was monitored with two personal dosimeters during 3 consecutive years. To measure the doses uniformly the two dosimeters were worn in a special holder attached to the lead apron. The two personal dosimeters were replaced every 4 weeks on the same day. The doses above and under the protective aprons of seven radiologists did not differ significantly. A significant lower dose above and under the protective apron was measured for one of the radiologists. During a 4-week period the average dose measured above the lead apron was 3.44 mSv (median, 3.05 mSv), while that under the 0.25-mm lead apron was 0.12 mSv (median, 0.1 mSv). The coefficients of the regression line result in the equation Y = 0.036X - 0.004, with Y as the dose under the lead apron and X as the dose above the lead apron. The statistical analysis of the data established a linear relation between the doses above and those under the lead apron (R 2 = 0.59). Before the special holder was introduced it was not possible to derive a relation between the doses above and those under the lead apron, as the doses were measured at varying places above and under the lead apron. There is no evidence that the effective dose can be estimated more accurately when an additional dosimeter is used. The present study revealed a threshold before doses under the lead apron were measured. Due to the threshold it can be concluded that the doses under the lead apron will not be underestimated easily when doses above the

Optical vector network analyzer with improved accuracy based on polarization modulation and polarization pulling.

Science.gov (United States)

Li, Wei; Liu, Jian Guo; Zhu, Ning Hua

2015-04-15

We report a novel optical vector network analyzer (OVNA) with improved accuracy based on polarization modulation and stimulated Brillouin scattering (SBS) assisted polarization pulling. The beating between adjacent higher-order optical sidebands which are generated because of the nonlinearity of an electro-optic modulator (EOM) introduces considerable error to the OVNA. In our scheme, the measurement error is significantly reduced by removing the even-order optical sidebands using polarization discrimination. The proposed approach is theoretically analyzed and experimentally verified. The experimental results show that the accuracy of the OVNA is greatly improved compared to a conventional OVNA.

Hybrid Indoor-Based WLAN-WSN Localization Scheme for Improving Accuracy Based on Artificial Neural Network

Directory of Open Access Journals (Sweden)

Zahid Farid

2016-01-01

Full Text Available In indoor environments, WiFi (RSS based localization is sensitive to various indoor fading effects and noise during transmission, which are the main causes of localization errors that affect its accuracy. Keeping in view those fading effects, positioning systems based on a single technology are ineffective in performing accurate localization. For this reason, the trend is toward the use of hybrid positioning systems (combination of two or more wireless technologies in indoor/outdoor localization scenarios for getting better position accuracy. This paper presents a hybrid technique to implement indoor localization that adopts fingerprinting approaches in both WiFi and Wireless Sensor Networks (WSNs. This model exploits machine learning, in particular Artificial Natural Network (ANN techniques, for position calculation. The experimental results show that the proposed hybrid system improved the accuracy, reducing the average distance error to 1.05 m by using ANN. Applying Genetic Algorithm (GA based optimization technique did not incur any further improvement to the accuracy. Compared to the performance of GA optimization, the nonoptimized ANN performed better in terms of accuracy, precision, stability, and computational time. The above results show that the proposed hybrid technique is promising for achieving better accuracy in real-world positioning applications.

Frequency of recommendations for additional imaging in diagnostic ultrasound examinations: Evaluation of radiologist, technologist, and other examination-related factors.

Science.gov (United States)

Margolis, Nathaniel E; Rosenkrantz, Andrew B; Babb, James S; Macari, Michael

2015-10-01

Our aim in this study was to evaluate the effect of the radiologist, technologist, and other examination-related factors on the frequency of recommendations for additional imaging (RAI) during sonographic (US) interpretation. We retrospectively reviewed 719 US reports from a single academic medical center for the presence of RAI. All studies had been interpreted by one of three abdominal radiologists. Examinations were performed at an outpatient radiology facility with no onsite radiologist (n = 299) or at an inpatient emergency department or hospital-based outpatient setting that had an onsite radiologist (n = 420). Possible associations between the frequency of RAI and the presence of an onsite radiologist, location of the examination, body part or region imaged, patient age, technologist performing the exam, and radiologist reading the exam were evaluated. There were significant differences between each pair of radiologists in terms of overall frequency of RAI (p technologists (13.6%-40.0%, p = 0.03). However, other factors such as patient age, patient sex, US unit, patient location, and radiologist location were not associated with the frequency of RAI (p = 0.15-0.93). The individual radiologist and technologist influenced the frequency of RAI for US examinations, whereas other examination-related factors did not. The observed substantial variability in RAI between radiologists and technologists warrants further study, with consideration of strategies to optimize RAI within US reports. © 2015 Wiley Periodicals, Inc.

Accuracy and efficacy of percutaneous biopsy and ablation using robotic assistance under computed tomography guidance: a phantom study

International Nuclear Information System (INIS)

Koethe, Yilun; Xu, Sheng; Velusamy, Gnanasekar; Wood, Bradford J.; Venkatesan, Aradhana M.

2014-01-01

To compare the accuracy of a robotic interventional radiologist (IR) assistance platform with a standard freehand technique for computed-tomography (CT)-guided biopsy and simulated radiofrequency ablation (RFA). The accuracy of freehand single-pass needle insertions into abdominal phantoms was compared with insertions facilitated with the use of a robotic assistance platform (n = 20 each). Post-procedural CTs were analysed for needle placement error. Percutaneous RFA was simulated by sequentially placing five 17-gauge needle introducers into 5-cm diameter masses (n = 5) embedded within an abdominal phantom. Simulated ablations were planned based on pre-procedural CT, before multi-probe placement was executed freehand. Multi-probe placement was then performed on the same 5-cm mass using the ablation planning software and robotic assistance. Post-procedural CTs were analysed to determine the percentage of untreated residual target. Mean needle tip-to-target errors were reduced with use of the IR assistance platform (both P < 0.0001). Reduced percentage residual tumour was observed with treatment planning (P = 0.02). Improved needle accuracy and optimised probe geometry are observed during simulated CT-guided biopsy and percutaneous ablation with use of a robotic IR assistance platform. This technology may be useful for clinical CT-guided biopsy and RFA, when accuracy may have an impact on outcome. (orig.)

Accuracy and efficacy of percutaneous biopsy and ablation using robotic assistance under computed tomography guidance: a phantom study

Energy Technology Data Exchange (ETDEWEB)

Koethe, Yilun [National Institutes of Health, Center for Interventional Oncology, NIH Clinical Center, Bethesda, MD (United States); National Institutes of Health, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, MD (United States); Duke University School of Medicine, Durham, NC (United States); Xu, Sheng [National Institutes of Health, Center for Interventional Oncology, NIH Clinical Center, Bethesda, MD (United States); Velusamy, Gnanasekar [Perfint Healthcare Pvt. Ltd., Chennai (India); Wood, Bradford J. [National Institutes of Health, Center for Interventional Oncology, NIH Clinical Center, Bethesda, MD (United States); National Institutes of Health, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, MD (United States); Venkatesan, Aradhana M. [National Institutes of Health, Center for Interventional Oncology, NIH Clinical Center, Bethesda, MD (United States); National Institutes of Health, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, MD (United States); National Institutes of Health, Center for Interventional Oncology, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, MD (United States)

2014-03-15

To compare the accuracy of a robotic interventional radiologist (IR) assistance platform with a standard freehand technique for computed-tomography (CT)-guided biopsy and simulated radiofrequency ablation (RFA). The accuracy of freehand single-pass needle insertions into abdominal phantoms was compared with insertions facilitated with the use of a robotic assistance platform (n = 20 each). Post-procedural CTs were analysed for needle placement error. Percutaneous RFA was simulated by sequentially placing five 17-gauge needle introducers into 5-cm diameter masses (n = 5) embedded within an abdominal phantom. Simulated ablations were planned based on pre-procedural CT, before multi-probe placement was executed freehand. Multi-probe placement was then performed on the same 5-cm mass using the ablation planning software and robotic assistance. Post-procedural CTs were analysed to determine the percentage of untreated residual target. Mean needle tip-to-target errors were reduced with use of the IR assistance platform (both P < 0.0001). Reduced percentage residual tumour was observed with treatment planning (P = 0.02). Improved needle accuracy and optimised probe geometry are observed during simulated CT-guided biopsy and percutaneous ablation with use of a robotic IR assistance platform. This technology may be useful for clinical CT-guided biopsy and RFA, when accuracy may have an impact on outcome. (orig.)

Evaluation of the occupational doses of interventional radiologists

NARCIS (Netherlands)

Kuipers, Gerritjan; Velders, Xandra L.; de Winter, Robbert J.; Reekers, Jim A.; Piek, Jan J.

2008-01-01

The aim of the present study was to determine whether there is a linear relation between the doses measured above and those measured under the lead apron of the radiologists performing interventional procedures. To monitor radiation exposure the International Commission of Radiological Protection

Improving Accuracy of Influenza-Associated Hospitalization Rate Estimates

Science.gov (United States)

Reed, Carrie; Kirley, Pam Daily; Aragon, Deborah; Meek, James; Farley, Monica M.; Ryan, Patricia; Collins, Jim; Lynfield, Ruth; Baumbach, Joan; Zansky, Shelley; Bennett, Nancy M.; Fowler, Brian; Thomas, Ann; Lindegren, Mary L.; Atkinson, Annette; Finelli, Lyn; Chaves, Sandra S.

2015-01-01

Diagnostic test sensitivity affects rate estimates for laboratory-confirmed influenza–associated hospitalizations. We used data from FluSurv-NET, a national population-based surveillance system for laboratory-confirmed influenza hospitalizations, to capture diagnostic test type by patient age and influenza season. We calculated observed rates by age group and adjusted rates by test sensitivity. Test sensitivity was lowest in adults >65 years of age. For all ages, reverse transcription PCR was the most sensitive test, and use increased from 65 years. After 2009, hospitalization rates adjusted by test sensitivity were ≈15% higher for children 65 years of age. Test sensitivity adjustments improve the accuracy of hospitalization rate estimates. PMID:26292017

Applying a social network analysis (SNA) approach to understanding radiologists' performance in reading mammograms

Science.gov (United States)

Tavakoli Taba, Seyedamir; Hossain, Liaquat; Heard, Robert; Brennan, Patrick; Lee, Warwick; Lewis, Sarah

2017-03-01

Rationale and objectives: Observer performance has been widely studied through examining the characteristics of individuals. Applying a systems perspective, while understanding of the system's output, requires a study of the interactions between observers. This research explains a mixed methods approach to applying a social network analysis (SNA), together with a more traditional approach of examining personal/ individual characteristics in understanding observer performance in mammography. Materials and Methods: Using social networks theories and measures in order to understand observer performance, we designed a social networks survey instrument for collecting personal and network data about observers involved in mammography performance studies. We present the results of a study by our group where 31 Australian breast radiologists originally reviewed 60 mammographic cases (comprising of 20 abnormal and 40 normal cases) and then completed an online questionnaire about their social networks and personal characteristics. A jackknife free response operating characteristic (JAFROC) method was used to measure performance of radiologists. JAFROC was tested against various personal and network measures to verify the theoretical model. Results: The results from this study suggest a strong association between social networks and observer performance for Australian radiologists. Network factors accounted for 48% of variance in observer performance, in comparison to 15.5% for the personal characteristics for this study group. Conclusion: This study suggest a strong new direction for research into improving observer performance. Future studies in observer performance should consider social networks' influence as part of their research paradigm, with equal or greater vigour than traditional constructs of personal characteristics.

Accuracy of High-Resolution Ultrasonography in the Detection of Extensor Tendon Lacerations.

Science.gov (United States)

Dezfuli, Bobby; Taljanovic, Mihra S; Melville, David M; Krupinski, Elizabeth A; Sheppard, Joseph E

2016-02-01

Lacerations to the extensor mechanism are usually diagnosed clinically. Ultrasound (US) has been a growing diagnostic tool for tendon injuries since the 1990s. To date, there has been no publication establishing the accuracy and reliability of US in the evaluation of extensor mechanism lacerations in the hand. The purpose of this study is to determine the accuracy of US to detect extensor tendon injuries in the hand. Sixteen fingers and 4 thumbs in 4 fresh-frozen and thawed cadaveric hands were used. Sixty-eight 0.5-cm transverse skin lacerations were created. Twenty-seven extensor tendons were sharply transected. The remaining skin lacerations were used as sham dissection controls. One US technologist and one fellowship-trained musculoskeletal radiologist performed real-time dynamic US studies in and out of water bath. A second fellowship trained musculoskeletal radiologist subsequently reviewed the static US images. Dynamic and static US interpretation accuracy was assessed using dissection as "truth." All 27 extensor tendon lacerations and controls were identified correctly with dynamic imaging as either injury models that had a transected extensor tendon or sham controls with intact extensor tendons (sensitivity = 100%, specificity = 100%, positive predictive value = 1.0; all significantly greater than chance). Static imaging had a sensitivity of 85%, specificity of 89%, and accuracy of 88% (all significantly greater than chance). The results of the dynamic real time versus static US imaging were clearly different but did not reach statistical significance. Diagnostic US is a very accurate noninvasive study that can identify extensor mechanism injuries. Clinically suspected cases of acute extensor tendon injury scanned by high-frequency US can aid and/or confirm the diagnosis, with dynamic imaging providing added value compared to static. Ultrasonography, to aid in the diagnosis of extensor mechanism lacerations, can be successfully used in a reliable and

Improving physics education in radiology.

Science.gov (United States)

Hendee, William R

2007-08-01

Concern is growing that the physics education of radiologists is flawed and that without knowledge of physics principles and applications, mastery of the technology of medical imaging is impaired. Furthermore, it is proposed that a mastery of imaging technology is necessary to perfect the clinical acumen of radiologists and to preserve the quality, safety, and cost-effectiveness of imaging procedures. These issues were the focus of a multiorganizational educational summit on physics education of radiologists held in January 2006 in Atlanta. Recommendations for improving the physics education and knowledge of radiologists that evolved from this summit are presented here, together with progress made to date on their fulfillment.

Defining the abdominal radiologist based on the current U.S. job market.

Science.gov (United States)

Hoffman, David H; Rosenkrantz, Andrew B

2018-03-24

The purpose of the study is to characterize current practice patterns of abdominal radiologists based on work descriptions within job postings on numerous national radiology specialty websites. Job postings for either "abdominal" or "body" radiologists were searched weekly on five society websites (SAR, SCBT-MR, ARRS, ACR, RSNA) over a 1-year period. Postings were reviewed for various characteristics. Nine hundred and sixteen total ads for 341 unique abdominal radiologist positions were reviewed (34.6% academic, 64.2% private practice, 1.2% other). Postings occurred most commonly in March (12.3%) and least commonly in November (4.8%). States with most positions were Florida (27), California (26), and New York (24). Of postings delineating expectations of specific abdominal modalities, 67.4% mentioned MRI, 58.5% ultrasound, 41.1% fluoroscopy, 14.3% PET, and 54.0% interventions. Additional non-abdominal expectations included general radiology (28.7%), breast imaging (21.1%), and general nuclear medicine (9.7%). Additional skills included prostate MRI (7.0%), OBGYN ultrasound (5.0%), and CT colonoscopy (2.6%). 79.2% required an abdominal imaging fellowship (specifically a body MRI fellowship in 4.1%). By using job postings for abdominal radiologists, we have taken a practical approach to characterizing the current status of this subspecialty, reflecting recent job expectations and requirements. The large majority of positions required a body fellowship, and the positions commonly entailed a variety of skills beyond non-invasive diagnostic abdominal imaging. Of note, expectations of considerable minorities of positions included abdominal interventions, general radiology, and breast imaging. These insights may guide the development of abdominal radiology fellowships and mini-fellowships, as well as assist radiologists entering or returning to the job market.

Improvement of the accuracy of noise measurements by the two-amplifier correlation method.

Science.gov (United States)

Pellegrini, B; Basso, G; Fiori, G; Macucci, M; Maione, I A; Marconcini, P

2013-10-01

We present a novel method for device noise measurement, based on a two-channel cross-correlation technique and a direct "in situ" measurement of the transimpedance of the device under test (DUT), which allows improved accuracy with respect to what is available in the literature, in particular when the DUT is a nonlinear device. Detailed analytical expressions for the total residual noise are derived, and an experimental investigation of the increased accuracy provided by the method is performed.

Radiologists' preferences for digital mammographic display. The International Digital Mammography Development Group.

Science.gov (United States)

Pisano, E D; Cole, E B; Major, S; Zong, S; Hemminger, B M; Muller, K E; Johnston, R E; Walsh, R; Conant, E; Fajardo, L L; Feig, S A; Nishikawa, R M; Yaffe, M J; Williams, M B; Aylward, S R

2000-09-01

To determine the preferences of radiologists among eight different image processing algorithms applied to digital mammograms obtained for screening and diagnostic imaging tasks. Twenty-eight images representing histologically proved masses or calcifications were obtained by using three clinically available digital mammographic units. Images were processed and printed on film by using manual intensity windowing, histogram-based intensity windowing, mixture model intensity windowing, peripheral equalization, multiscale image contrast amplification (MUSICA), contrast-limited adaptive histogram equalization, Trex processing, and unsharp masking. Twelve radiologists compared the processed digital images with screen-film mammograms obtained in the same patient for breast cancer screening and breast lesion diagnosis. For the screening task, screen-film mammograms were preferred to all digital presentations, but the acceptability of images processed with Trex and MUSICA algorithms were not significantly different. All printed digital images were preferred to screen-film radiographs in the diagnosis of masses; mammograms processed with unsharp masking were significantly preferred. For the diagnosis of calcifications, no processed digital mammogram was preferred to screen-film mammograms. When digital mammograms were preferred to screen-film mammograms, radiologists selected different digital processing algorithms for each of three mammographic reading tasks and for different lesion types. Soft-copy display will eventually allow radiologists to select among these options more easily.

Standalone computer-aided detection compared to radiologists' performance for the detection of mammographic masses

International Nuclear Information System (INIS)

Hupse, Rianne; Samulski, Maurice; Imhof-Tas, Mechli W.; Karssemeijer, Nico; Lobbes, Marc; Boetes, Carla; Heeten, Ard den; Beijerinck, David; Pijnappel, Ruud

2013-01-01

We developed a computer-aided detection (CAD) system aimed at decision support for detection of malignant masses and architectural distortions in mammograms. The effect of this system on radiologists' performance depends strongly on its standalone performance. The purpose of this study was to compare the standalone performance of this CAD system to that of radiologists. In a retrospective study, nine certified screening radiologists and three residents read 200 digital screening mammograms without the use of CAD. Performances of the individual readers and of CAD were computed as the true-positive fraction (TPF) at a false-positive fraction of 0.05 and 0.2. Differences were analysed using an independent one-sample t-test. At a false-positive fraction of 0.05, the performance of CAD (TPF = 0.487) was similar to that of the certified screening radiologists (TPF = 0.518, P = 0.17). At a false-positive fraction of 0.2, CAD performance (TPF = 0.620) was significantly lower than the radiologist performance (TPF = 0.736, P <0.001). Compared to the residents, CAD performance was similar for all false-positive fractions. The sensitivity of CAD at a high specificity was comparable to that of human readers. These results show potential for CAD to be used as an independent reader in breast cancer screening. (orig.)

Pressure injectors for radiologists: A review and what is new

International Nuclear Information System (INIS)

Indrajit, Inna K; Sivasankar, Rajeev; D’Souza, John; Pant, Rochan; Negi, Raj S; Sahu, Samresh; Hashim, PI

2015-01-01

Pressure Injectors are used routinely in diagnostic and interventional radiology. Advances in medical science and technology have made it is imperative for both diagnostic as well as interventional radiologists to have a thorough understanding of the various aspects of pressure injectors. Further, as many radiologists may not be fully conversant with injections into ports, central lines and PICCs, it is important to familiarize oneself with the same. It is also important to follow stringent operating protocols during the use of pressure injectors to prevent complications such as contrast extravastion, sepsis and air embolism. This article aims to update existing knowledge base in this respect

Improved accuracy of intraocular lens power calculation with the Zeiss IOLMaster.

Science.gov (United States)

Olsen, Thomas

2007-02-01

This study aimed to demonstrate how the level of accuracy in intraocular lens (IOL) power calculation can be improved with optical biometry using partial optical coherence interferometry (PCI) (Zeiss IOLMaster) and current anterior chamber depth (ACD) prediction algorithms. Intraocular lens power in 461 consecutive cataract operations was calculated using both PCI and ultrasound and the accuracy of the results of each technique were compared. To illustrate the importance of ACD prediction per se, predictions were calculated using both a recently published 5-variable method and the Haigis 2-variable method and the results compared. All calculations were optimized in retrospect to account for systematic errors, including IOL constants and other off-set errors. The average absolute IOL prediction error (observed minus expected refraction) was 0.65 dioptres with ultrasound and 0.43 D with PCI using the 5-variable ACD prediction method (p ultrasound, respectively (p power calculation can be significantly improved using calibrated axial length readings obtained with PCI and modern IOL power calculation formulas incorporating the latest generation ACD prediction algorithms.

Improving the accuracy of Laplacian estimation with novel multipolar concentric ring electrodes

Science.gov (United States)

Ding, Quan; Besio, Walter G.

2015-01-01

Conventional electroencephalography with disc electrodes has major drawbacks including poor spatial resolution, selectivity and low signal-to-noise ratio that are critically limiting its use. Concentric ring electrodes, consisting of several elements including the central disc and a number of concentric rings, are a promising alternative with potential to improve all of the aforementioned aspects significantly. In our previous work, the tripolar concentric ring electrode was successfully used in a wide range of applications demonstrating its superiority to conventional disc electrode, in particular, in accuracy of Laplacian estimation. This paper takes the next step toward further improving the Laplacian estimation with novel multipolar concentric ring electrodes by completing and validating a general approach to estimation of the Laplacian for an (n + 1)-polar electrode with n rings using the (4n + 1)-point method for n ≥ 2 that allows cancellation of all the truncation terms up to the order of 2n. An explicit formula based on inversion of a square Vandermonde matrix is derived to make computation of multipolar Laplacian more efficient. To confirm the analytic result of the accuracy of Laplacian estimate increasing with the increase of n and to assess the significance of this gain in accuracy for practical applications finite element method model analysis has been performed. Multipolar concentric ring electrode configurations with n ranging from 1 ring (bipolar electrode configuration) to 6 rings (septapolar electrode configuration) were directly compared and obtained results suggest the significance of the increase in Laplacian accuracy caused by increase of n. PMID:26693200

Improving Intensity-Based Lung CT Registration Accuracy Utilizing Vascular Information

Directory of Open Access Journals (Sweden)

Kunlin Cao

2012-01-01

Full Text Available Accurate pulmonary image registration is a challenging problem when the lungs have a deformation with large distance. In this work, we present a nonrigid volumetric registration algorithm to track lung motion between a pair of intrasubject CT images acquired at different inflation levels and introduce a new vesselness similarity cost that improves intensity-only registration. Volumetric CT datasets from six human subjects were used in this study. The performance of four intensity-only registration algorithms was compared with and without adding the vesselness similarity cost function. Matching accuracy was evaluated using landmarks, vessel tree, and fissure planes. The Jacobian determinant of the transformation was used to reveal the deformation pattern of local parenchymal tissue. The average matching error for intensity-only registration methods was on the order of 1 mm at landmarks and 1.5 mm on fissure planes. After adding the vesselness preserving cost function, the landmark and fissure positioning errors decreased approximately by 25% and 30%, respectively. The vesselness cost function effectively helped improve the registration accuracy in regions near thoracic cage and near the diaphragm for all the intensity-only registration algorithms tested and also helped produce more consistent and more reliable patterns of regional tissue deformation.

Accuracy of radiographer reporting of paediatric brain CT

International Nuclear Information System (INIS)

Brandt, Andrew; Louw, Brand; Dekker, Gerrit; Andronikou, Savvas; Wieselthaler, Nicki; Kilborn, Tracy; Bertelsman, Jessica; Dreyer, Catherine

2007-01-01

Radiographer reporting has been studied for plain films and for ultrasonography, but not in paediatric brain CT in the emergency setting. To study the accuracy of radiographer reporting in paediatric brain CT. We prospectively collected 100 paediatric brain CT examinations. Films were read from hard copies using a prescribed tick sheet. Radiographers with 12 years' and 3 years' experience, respectively, were blinded to the history and were not trained in diagnostic film interpretation. The radiographers' results were compared with those of a consultant radiologist. Three categories were defined: abnormal scans, significant abnormalities and insignificant abnormalities. Both radiographers had an accuracy of 89.5% in reading a scan correctly as abnormal, and radiographer 1 had a sensitivity of 87.8% and radiographer 2 a sensitivity of 96%. Radiographer 1 had an accuracy in detecting a significant abnormality of 75% and radiographer 2 an accuracy of 48.6%, and the sensitivities for this category were 61.6% and 52.9%, respectively. Results for detecting the insignificant abnormalities were poorer. Selected radiographers could play an effective screening role, but lacking the sensitivity required for detecting significant abnormality, they could not be the final diagnostician. We recommend that the study be repeated after both radiographers have received formal training in interpretation of paediatric brain CT. (orig.)

Radiographer and radiologist perception error in reporting double contrast barium enemas: A pilot study

International Nuclear Information System (INIS)

Booth, Alison M.; Mannion, Richard A.J.

2005-01-01

Purpose: The practice of radiographers performing double contrast barium enemas (DCBE) is now widespread and in many centres the radiographer's opinion is, at least, contributing to a dual reporting system [Bewell J, Chapman AH. Radiographer performed barium enemas - results of a survey to assess progress. Radiography 1996;2:199-205; Leslie A, Virjee JP. Detection of colorectal carcinoma on double contrast barium enema when double reporting is routinely performed: an audit of current practice. Clin Radiol 2001;57:184-7; Culpan DG, Mitchell AJ, Hughes S, Nutman M, Chapman AH. Double contrast barium enema sensitivity: a comparison of studies by radiographers and radiologists. Clin Radiol 2002;57:604-7]. To ensure this change in practice does not lead to an increase in reporting errors, this study aimed to compare the perception abilities of radiographers with those of radiologists. Methods: Three gastro-intestinal (GI) radiographers and three consultant radiologists independently reported on a selection of 50 DCBE examinations, including the level of certainty in their comments for each examination. A blinded comparison of the results with an independent 'standard report' was recorded. Results: The results demonstrate there was no significant difference in perception error for any of the levels of certainty, for single reporting, for double reading by a radiographer/radiologist or by two radiologists. Conclusions: The study shows that radiographers can perceive abnormalities on DCBE at similar sensitivities and specificities as radiologists. While the participants in the study may be typical of a district general hospital, the nature of the study gives it limited external validity. As a pilot, the results demonstrate that, with slight modification, the methodology could be used for a larger study

CT colonography: interpretative performance in a non-academic environment

International Nuclear Information System (INIS)

Burling, D.; Halligan, S.; Atchley, J.; Dhingsar, R.; Guest, P.; Hayward, S.; Higginson, A.; Jobling, C.; Kay, C.; Lilford, R.; Maskell, G.; McCafferty, I.; McGregor, J.; Morton, D.; Kumar Neelala, M.; Noakes, M.; Philips, A.; Riley, P.; Taylor, A.; Bassett, P.; Wardle, J.; Atkin, W.; Taylor, S.A.

2007-01-01

Aim: To investigate interpretative accuracy and reporting time for radiologists performing computed tomography (CT) colonography in day-to-day non-academic clinical practice. Materials and methods: Thirteen radiologists from seven centres, who were reporting CT colonography in non-academic daily clinical practice, interpreted a dataset of 15 colonoscopically validated cases in a controlled environment. Ten cases had either a cancer or polyp >10 mm; one case had a medium polyp and four were normal. Correct case categorization and interpretation times were compared using analysis of variance to aggregated results obtained from both experienced observers and observers recently trained using 50 cases, working in an academic environment. The effect of experience was determined using Spearman's rank correlation. Results: Individual accuracy was highly variable, range 53% (95% CI 27-79%) to 93% (95% CI 68-100%). Mean accuracy overall was significantly inferior to experienced radiologists (mean 75 versus 88%, p = 0.04) but not significantly different from recently trained radiologists (p = 0.48). Interpretation time was not significantly different to experienced readers (mean 12.4 min versus 11.7, p = 0.74), but shorter than recently trained radiologists (p = 0.05). There was a significant, positive, linear correlation between prior experience and accuracy (p < 0.001) with no plateau. Conclusion: Accuracy for sub-specialist radiologists working in a non-academic environment is, on average, equivalent to radiologists trained using 50 cases. However, there is wide variability in individual performance, which generally falls short of the average performance suggested by meta-analysis of published data. Experience improves accuracy, but alone is insufficient to determine competence

Improvement of Accuracy in Environmental Dosimetry by TLD Cards Using Three-dimensional Calibration Method

Directory of Open Access Journals (Sweden)

HosseiniAliabadi S. J.

2015-06-01

Full Text Available Background: The angular dependency of response for TLD cards may cause deviation from its true value on the results of environmental dosimetry, since TLDs may be exposed to radiation at different angles of incidence from the surrounding area. Objective: A 3D setting of TLD cards has been calibrated isotropically in a standard radiation field to evaluate the improvement of the accuracy of measurement for environmental dosimetry. Method: Three personal TLD cards were rectangularly placed in a cylindrical holder, and calibrated using 1D and 3D calibration methods. Then, the dosimeter has been used simultaneously with a reference instrument in a real radiation field measuring the accumulated dose within a time interval. Result: The results show that the accuracy of measurement has been improved by 6.5% using 3D calibration factor in comparison with that of normal 1D calibration method. Conclusion: This system can be utilized in large scale environmental monitoring with a higher accuracy

The role of a consultant radiologist - are patients still in the dark?

Energy Technology Data Exchange (ETDEWEB)

Grant, L.; Griffin, N.; McDonald, S.; Vargas, H.; Hampson, F.; Sinnatamby, R. [Cambridge University Teaching Hospitals, NHS Foundation Trust, Department of Radiology, Cambridge (United Kingdom); Vasconcelos, J.C. [University of Cambridge, Centre for Applied Medical Statistics, Department of Public Health and Primary Care, Cambridge (United Kingdom)

2009-10-15

Little is known regarding public awareness of the roles and responsibilities of a consultant radiologist. Between 1 April and 20 May 2008, 916 outpatients attending our radiology department completed a questionnaire addressing this issue. We found public perception variable. Thirty-six percent of respondents thought we were responsible for choosing appropriate imaging; only 65% perceived that we reported studies. Another 38% felt that we did not play an important role in their treatment, and 38% considered that we were not part of their medical team. Thirty-two percent of respondents preferred their hospital consultant to give them their imaging results, with 17% preferring this to come from the radiologist. There is significant under-appreciation of the roles and responsibilities of a consultant radiologist. It is important that we educate the public to ensure that future health policy reflects the increasingly central role imaging plays in health-care delivery. (orig.)

Interdisciplinary shock-room care: tasks for the radiologist from the viewpoint of the trauma surgeon

International Nuclear Information System (INIS)

Mutschler, W.; Kanz, K.G.

2002-01-01

Efficient resuscitation of major trauma requests an interdisciplinary communication between trauma surgeons, anaesthesiologists and radiologists. Trauma outcome is significantly influenced by horizontal trauma team organisation and coherence to clinical algorithms, which allow fast diagnosis and intervention. A radiologist present on patients arrival in the trauma room provides a major impact on trauma care. Nevertheless optimal integration in the trauma team implies profound knowledge of the priorities of advanced trauma life support and trauma algorithms. His or her involvement is not limited to patient care only, also active participation in trauma room design, interdisciplinary algorithm development and trauma research are essential tasks for radiologists devoted to emergency radiology. Based on the pathophysiology of polytrauma and the structure of German trauma system, current concepts and proven clinical algorithms with special regard to the radiologist and his duties and tasks will are presented. (orig.) [de

Preliminary reports in the emergency department: is a subspecialist radiologist more accurate than a radiology resident?

Science.gov (United States)

Branstetter, Barton F; Morgan, Matthew B; Nesbit, Chadd E; Phillips, Jinnah A; Lionetti, David M; Chang, Paul J; Towers, Jeffrey D

2007-02-01

To determine whether emergency department (ED) preliminary reports rendered by subspecialist attending radiologists who are reading outside their field of expertise are more accurate than reports rendered by radiology residents, and to compare error rates between radiologists and nonradiologists in the ED setting. The study was performed at a large academic medical center with a busy ED. An electronic preliminary report generator was used in the ED to capture preliminary interpretations rendered in a clinical setting by radiology residents, junior attendings (within 2 years of taking their oral boards), senior attendings, and ED clinicians between August 1999 and November 2004. Each preliminary report was later reviewed by a final interpreting radiologist, and the preliminary interpretation was adjudicated for the presence of substantial discordances, defined as a difference in interpretation that might immediately impact the care of the patient. Of the 612,890 preliminary reports in the database, 65,780 (11%) met inclusion criteria for this study. A log-linear analysis was used to assess the effects of modality and type of author on preliminary report error rates. ED clinicians had significantly higher error rates when compared with any type of radiologist, regardless of modality. Within the radiologists, residents and junior attendings had lower error rates than did senior attendings, but the differences were not statistically significant. Subspecialized attending radiologists who interpret ED examinations outside their area of expertise have error rates similar to those of radiology residents. Nonradiologists have significantly higher error rates than radiologists and radiology residents when interpreting examinations in the ED.

Angled oblique sagittal MR imaging of rotator cuff tears: comparison with standard oblique sagittal images

International Nuclear Information System (INIS)

Tuite, M.J.; Asinger, D.; Orwin, J.F.

2001-01-01

Objective. To compare the accuracy for diagnosing rotator cuff tears of oblique coronal images supplemented with standard oblique sagittal images versus thinner-section angled oblique sagittal images.Design and patients. The study included 75 consecutive patients who had a shoulder MR scan followed by arthroscopy. MR images included oblique coronal, oblique sagittal (4 mm thick, 1 mm interslice gap), and angled oblique sagittal (3 mm/0.2 mm) images perpendicular to the lateral cuff. A musculoskeletal staff radiologist and fellow separately evaluated the cuff for tears on the oblique coronal images supplemented with either the oblique sagittal or the angled sagittal images.Results. For distinguishing a cuff tear from no tear, the staff radiologist had an accuracy of 0.76 (95% confidence interval: 0.67, 0.85) with the standard sagittal set, and 0.88 (0.80, 0.95) with the angled set (P=0.04). There was a nonsignificant improvement in accuracy for the fellow, calculated as 0.73 (0.63, 0.83) on the standard sagittal set and 0.76 (0.67, 0.85) on the angled set. Both readers also improved their diagnostic accuracy for partial-thickness tears with the angled set, although the improvement was statistically significant only for the staff radiologist.Conclusion. There is a slight improvement in accuracy for diagnosing rotator cuff tears, particularly partial-thickness tears, for the more experienced radiologist using thinner-section angled oblique sagittal images. These images may be useful as a supplemental sequence in patients where it is important to identify partial-thickness tears accurately. (orig.)

Angled oblique sagittal MR imaging of rotator cuff tears: comparison with standard oblique sagittal images

Energy Technology Data Exchange (ETDEWEB)

Tuite, M J; Asinger, D; Orwin, J F [Dept. of Radiology, Univ. of Wisconsin Hospital and Clinics, Madison, WI (United States)

2001-05-01

Objective. To compare the accuracy for diagnosing rotator cuff tears of oblique coronal images supplemented with standard oblique sagittal images versus thinner-section angled oblique sagittal images.Design and patients. The study included 75 consecutive patients who had a shoulder MR scan followed by arthroscopy. MR images included oblique coronal, oblique sagittal (4 mm thick, 1 mm interslice gap), and angled oblique sagittal (3 mm/0.2 mm) images perpendicular to the lateral cuff. A musculoskeletal staff radiologist and fellow separately evaluated the cuff for tears on the oblique coronal images supplemented with either the oblique sagittal or the angled sagittal images.Results. For distinguishing a cuff tear from no tear, the staff radiologist had an accuracy of 0.76 (95% confidence interval: 0.67, 0.85) with the standard sagittal set, and 0.88 (0.80, 0.95) with the angled set (P=0.04). There was a nonsignificant improvement in accuracy for the fellow, calculated as 0.73 (0.63, 0.83) on the standard sagittal set and 0.76 (0.67, 0.85) on the angled set. Both readers also improved their diagnostic accuracy for partial-thickness tears with the angled set, although the improvement was statistically significant only for the staff radiologist.Conclusion. There is a slight improvement in accuracy for diagnosing rotator cuff tears, particularly partial-thickness tears, for the more experienced radiologist using thinner-section angled oblique sagittal images. These images may be useful as a supplemental sequence in patients where it is important to identify partial-thickness tears accurately. (orig.)

Assessing Doses to Interventional Radiologists Using a Personal Dosimeter Worn Over a Protective Apron

Energy Technology Data Exchange (ETDEWEB)

Stranden, E.; Widmark, A.; Sekse, T. (Buskerud Univ. College, Drammen (Norway))

2008-05-15

Background: Interventional radiologists receive significant radiation doses, and it is important to have simple methods for routine monitoring of their exposure. Purpose: To evaluate the usefulness of a dosimeter worn outside the protective apron for assessments of dose to interventional radiologists. Material and Methods: Assessments of effective dose versus dose to dosimeters worn outside the protective apron were achieved by phantom measurements. Doses outside and under the apron were assessed by phantom measurements and measurements on eight radiologists wearing two routine dosimeters for a 2-month period during ordinary working conditions. Finger doses for the same radiologists were recorded using thermoluminescent dosimeters (TLD; DXT-RAD Extremity dosimeters). Results: Typical values for the ratio between effective dose and dosimeter dose were found to be about 0.02 when the radiologist used a thyroid shield and about 0.03 without. The ratio between the dose to the dosimeter under and outside a protective apron was found to be less than 0.04. There was very good correlation between finger dose and dosimeter dose. Conclusion: A personal dosimeter worn outside a protective apron is a good screening device for dose to the eyes and fingers as well as for effective dose, even though the effective dose is grossly overestimated. Relatively high dose to the fingers and eyes remains undetected by a dosimeter worn under the apron

Assessing Doses to Interventional Radiologists Using a Personal Dosimeter Worn Over a Protective Apron

International Nuclear Information System (INIS)

Stranden, E.; Widmark, A.; Sekse, T.

2008-01-01

Background: Interventional radiologists receive significant radiation doses, and it is important to have simple methods for routine monitoring of their exposure. Purpose: To evaluate the usefulness of a dosimeter worn outside the protective apron for assessments of dose to interventional radiologists. Material and Methods: Assessments of effective dose versus dose to dosimeters worn outside the protective apron were achieved by phantom measurements. Doses outside and under the apron were assessed by phantom measurements and measurements on eight radiologists wearing two routine dosimeters for a 2-month period during ordinary working conditions. Finger doses for the same radiologists were recorded using thermoluminescent dosimeters (TLD; DXT-RAD Extremity dosimeters). Results: Typical values for the ratio between effective dose and dosimeter dose were found to be about 0.02 when the radiologist used a thyroid shield and about 0.03 without. The ratio between the dose to the dosimeter under and outside a protective apron was found to be less than 0.04. There was very good correlation between finger dose and dosimeter dose. Conclusion: A personal dosimeter worn outside a protective apron is a good screening device for dose to the eyes and fingers as well as for effective dose, even though the effective dose is grossly overestimated. Relatively high dose to the fingers and eyes remains undetected by a dosimeter worn under the apron

Medical 3D Printing for the Radiologist

Science.gov (United States)

Mitsouras, Dimitris; Liacouras, Peter; Imanzadeh, Amir; Giannopoulos, Andreas A.; Cai, Tianrun; Kumamaru, Kanako K.; George, Elizabeth; Wake, Nicole; Caterson, Edward J.; Pomahac, Bohdan; Ho, Vincent B.; Grant, Gerald T.

2015-01-01

While use of advanced visualization in radiology is instrumental in diagnosis and communication with referring clinicians, there is an unmet need to render Digital Imaging and Communications in Medicine (DICOM) images as three-dimensional (3D) printed models capable of providing both tactile feedback and tangible depth information about anatomic and pathologic states. Three-dimensional printed models, already entrenched in the nonmedical sciences, are rapidly being embraced in medicine as well as in the lay community. Incorporating 3D printing from images generated and interpreted by radiologists presents particular challenges, including training, materials and equipment, and guidelines. The overall costs of a 3D printing laboratory must be balanced by the clinical benefits. It is expected that the number of 3D-printed models generated from DICOM images for planning interventions and fabricating implants will grow exponentially. Radiologists should at a minimum be familiar with 3D printing as it relates to their field, including types of 3D printing technologies and materials used to create 3D-printed anatomic models, published applications of models to date, and clinical benefits in radiology. Online supplemental material is available for this article. ©RSNA, 2015 PMID:26562233

Medical 3D Printing for the Radiologist.

Science.gov (United States)

Mitsouras, Dimitris; Liacouras, Peter; Imanzadeh, Amir; Giannopoulos, Andreas A; Cai, Tianrun; Kumamaru, Kanako K; George, Elizabeth; Wake, Nicole; Caterson, Edward J; Pomahac, Bohdan; Ho, Vincent B; Grant, Gerald T; Rybicki, Frank J

2015-01-01

While use of advanced visualization in radiology is instrumental in diagnosis and communication with referring clinicians, there is an unmet need to render Digital Imaging and Communications in Medicine (DICOM) images as three-dimensional (3D) printed models capable of providing both tactile feedback and tangible depth information about anatomic and pathologic states. Three-dimensional printed models, already entrenched in the nonmedical sciences, are rapidly being embraced in medicine as well as in the lay community. Incorporating 3D printing from images generated and interpreted by radiologists presents particular challenges, including training, materials and equipment, and guidelines. The overall costs of a 3D printing laboratory must be balanced by the clinical benefits. It is expected that the number of 3D-printed models generated from DICOM images for planning interventions and fabricating implants will grow exponentially. Radiologists should at a minimum be familiar with 3D printing as it relates to their field, including types of 3D printing technologies and materials used to create 3D-printed anatomic models, published applications of models to date, and clinical benefits in radiology. Online supplemental material is available for this article. (©)RSNA, 2015.

Application of FFTBM with signal mirroring to improve accuracy assessment of MELCOR code

International Nuclear Information System (INIS)

Saghafi, Mahdi; Ghofrani, Mohammad Bagher; D’Auria, Francesco

2016-01-01

Highlights: • FFTBM-SM is an improved Fast Fourier Transform Base Method by signal mirroring. • FFTBM-SM has been applied to accuracy assessment of MELCOR code predictions. • The case studied was Station Black-Out accident in PSB-VVER integral test facility. • FFTBM-SM eliminates fluctuations of accuracy indices when signals sharply change. • Accuracy assessment is performed in a more realistic and consistent way by FFTBM-SM. - Abstract: This paper deals with the application of Fast Fourier Transform Base Method (FFTBM) with signal mirroring (FFTBM-SM) to assess accuracy of MELCOR code. This provides deeper insights into how the accuracy of MELCOR code in predictions of thermal-hydraulic parameters varies during transients. The case studied was modeling of Station Black-Out (SBO) accident in PSB-VVER integral test facility by MELCOR code. The accuracy of this thermal-hydraulic modeling was previously quantified using original FFTBM in a few number of time-intervals, based on phenomenological windows of SBO accident. Accuracy indices calculated by original FFTBM in a series of time-intervals unreasonably fluctuate when the investigated signals sharply increase or decrease. In the current study, accuracy of MELCOR code is quantified using FFTBM-SM in a series of increasing time-intervals, and the results are compared to those with original FFTBM. Also, differences between the accuracy indices of original FFTBM and FFTBM-SM are investigated and correction factors calculated to eliminate unphysical effects in original FFTBM. The main findings are: (1) replacing limited number of phenomena-based time-intervals by a series of increasing time-intervals provides deeper insights about accuracy variation of the MELCOR calculations, and (2) application of FFTBM-SM for accuracy evaluation of the MELCOR predictions, provides more reliable results than original FFTBM by eliminating the fluctuations of accuracy indices when experimental signals sharply increase or

Application of FFTBM with signal mirroring to improve accuracy assessment of MELCOR code

Energy Technology Data Exchange (ETDEWEB)

Saghafi, Mahdi [Department of Energy Engineering, Sharif University of Technology, Azadi Avenue, Tehran (Iran, Islamic Republic of); Ghofrani, Mohammad Bagher, E-mail: ghofrani@sharif.edu [Department of Energy Engineering, Sharif University of Technology, Azadi Avenue, Tehran (Iran, Islamic Republic of); D’Auria, Francesco [San Piero a Grado Nuclear Research Group (GRNSPG), University of Pisa, Via Livornese 1291, San Piero a Grado, Pisa (Italy)

2016-11-15

Highlights: • FFTBM-SM is an improved Fast Fourier Transform Base Method by signal mirroring. • FFTBM-SM has been applied to accuracy assessment of MELCOR code predictions. • The case studied was Station Black-Out accident in PSB-VVER integral test facility. • FFTBM-SM eliminates fluctuations of accuracy indices when signals sharply change. • Accuracy assessment is performed in a more realistic and consistent way by FFTBM-SM. - Abstract: This paper deals with the application of Fast Fourier Transform Base Method (FFTBM) with signal mirroring (FFTBM-SM) to assess accuracy of MELCOR code. This provides deeper insights into how the accuracy of MELCOR code in predictions of thermal-hydraulic parameters varies during transients. The case studied was modeling of Station Black-Out (SBO) accident in PSB-VVER integral test facility by MELCOR code. The accuracy of this thermal-hydraulic modeling was previously quantified using original FFTBM in a few number of time-intervals, based on phenomenological windows of SBO accident. Accuracy indices calculated by original FFTBM in a series of time-intervals unreasonably fluctuate when the investigated signals sharply increase or decrease. In the current study, accuracy of MELCOR code is quantified using FFTBM-SM in a series of increasing time-intervals, and the results are compared to those with original FFTBM. Also, differences between the accuracy indices of original FFTBM and FFTBM-SM are investigated and correction factors calculated to eliminate unphysical effects in original FFTBM. The main findings are: (1) replacing limited number of phenomena-based time-intervals by a series of increasing time-intervals provides deeper insights about accuracy variation of the MELCOR calculations, and (2) application of FFTBM-SM for accuracy evaluation of the MELCOR predictions, provides more reliable results than original FFTBM by eliminating the fluctuations of accuracy indices when experimental signals sharply increase or

a New Approach for Accuracy Improvement of Pulsed LIDAR Remote Sensing Data

Science.gov (United States)

Zhou, G.; Huang, W.; Zhou, X.; He, C.; Li, X.; Huang, Y.; Zhang, L.

2018-05-01

In remote sensing applications, the accuracy of time interval measurement is one of the most important parameters that affect the quality of pulsed lidar data. The traditional time interval measurement technique has the disadvantages of low measurement accuracy, complicated circuit structure and large error. A high-precision time interval data cannot be obtained in these traditional methods. In order to obtain higher quality of remote sensing cloud images based on the time interval measurement, a higher accuracy time interval measurement method is proposed. The method is based on charging the capacitance and sampling the change of capacitor voltage at the same time. Firstly, the approximate model of the capacitance voltage curve in the time of flight of pulse is fitted based on the sampled data. Then, the whole charging time is obtained with the fitting function. In this method, only a high-speed A/D sampler and capacitor are required in a single receiving channel, and the collected data is processed directly in the main control unit. The experimental results show that the proposed method can get error less than 3 ps. Compared with other methods, the proposed method improves the time interval accuracy by at least 20 %.

Assessment of surgical portosystemic shunts and associated complications: The diagnostic and therapeutic role of radiologists

Energy Technology Data Exchange (ETDEWEB)

Taslakian, Bedros, E-mail: btaslakian@gmail.com [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Faraj, Walid, E-mail: wf07@aub.edu.lb [Department of General Surgery, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Khalife, Mohammad, E-mail: mk12@aub.edu.lb [Department of General Surgery, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Al-Kutoubi, Aghiad, E-mail: mk00@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); El-Merhi, Fadi, E-mail: fe19@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Saade, Charbel, E-mail: cs39@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Hallal, Ali, E-mail: ah05@aub.edu.lb [Department of General Surgery, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon); Haydar, Ali, E-mail: ah24@aub.edu.lb [Department of Radiology, American University of Beirut Medical Center, Riad El-Solh 1107 2020—PO Box: 11-0236, Beirut (Lebanon)

2015-08-15

Highlights: • Portal hypertension is the pathological increase in portal venous pressure. • Surgical portosystemic shunting is an accepted methods to decrease portal venous pressure. • Surgical portosystemic shunts are divided into selective and nonselective. • Shunt thrombosis is a serious complication, resulting in shunt dysfunction. • Imaging is essential in the assessment of the shunt function and anatomy. - Abstract: Surgical portosystemic shunting, the formation of a vascular connection between the portal and systemic venous circulation, has been used as a treatment to reduce portal venous pressure. Although the use of portosystemic shunt surgery in the management of portal hypertension has declined during the past decade in favour of alternative therapies, and subsequently surgeons and radiologists became less familiar with the procedure, it remains a well-established treatment. Knowledge of different types of surgical portosystemic shunts, their pathophysiology and complications will help radiologists improve communication with surgeons and enhance their understanding of the diagnostic and therapeutic role of radiology in the assessment and management of these shunts. Optimal assessment of the shunt is essential to determine its patency and allow timely intervention. Both non-invasive and invasive imaging modalities complement each other in the evaluation of surgical portosystemic shunts. Interventional radiology plays an important role in the management of complications, such as shunt thrombosis and stenosis. This article describes the various types of surgical portosystemic shunts, explains the anatomy and pathophysiology of these shunts, illustrates the pearls and pitfalls of different imaging modalities in the assessment of these shunts and demonstrates the role of radiologists in the interventional management of complications.

Assessment of surgical portosystemic shunts and associated complications: The diagnostic and therapeutic role of radiologists

International Nuclear Information System (INIS)

Taslakian, Bedros; Faraj, Walid; Khalife, Mohammad; Al-Kutoubi, Aghiad; El-Merhi, Fadi; Saade, Charbel; Hallal, Ali; Haydar, Ali

2015-01-01

Highlights: • Portal hypertension is the pathological increase in portal venous pressure. • Surgical portosystemic shunting is an accepted methods to decrease portal venous pressure. • Surgical portosystemic shunts are divided into selective and nonselective. • Shunt thrombosis is a serious complication, resulting in shunt dysfunction. • Imaging is essential in the assessment of the shunt function and anatomy. - Abstract: Surgical portosystemic shunting, the formation of a vascular connection between the portal and systemic venous circulation, has been used as a treatment to reduce portal venous pressure. Although the use of portosystemic shunt surgery in the management of portal hypertension has declined during the past decade in favour of alternative therapies, and subsequently surgeons and radiologists became less familiar with the procedure, it remains a well-established treatment. Knowledge of different types of surgical portosystemic shunts, their pathophysiology and complications will help radiologists improve communication with surgeons and enhance their understanding of the diagnostic and therapeutic role of radiology in the assessment and management of these shunts. Optimal assessment of the shunt is essential to determine its patency and allow timely intervention. Both non-invasive and invasive imaging modalities complement each other in the evaluation of surgical portosystemic shunts. Interventional radiology plays an important role in the management of complications, such as shunt thrombosis and stenosis. This article describes the various types of surgical portosystemic shunts, explains the anatomy and pathophysiology of these shunts, illustrates the pearls and pitfalls of different imaging modalities in the assessment of these shunts and demonstrates the role of radiologists in the interventional management of complications

In-Person Communication Between Radiologists and Acute Care Surgeons Leads to Significant Alterations in Surgical Decision Making.

Science.gov (United States)

Dickerson, Elliot C; Alam, Hasan B; Brown, Richard K J; Stojanovska, Jadranka; Davenport, Matthew S

2016-08-01

The aim of this study was to determine if direct in-person communication between an acute care surgical team and radiologists alters surgical decision making. Informed consent was waived for this institutional review board-exempt, HIPAA-compliant, prospective quality improvement study. From January 29, 2015 to December 10, 2015, semiweekly rounds lasting approximately 60 min were held between the on-call acute care surgery team (attending surgeon, chief resident, and residents) and one of three expert abdominal radiologists. A comprehensive imaging review was performed of recent and comparison examinations for cases selected by the surgeons in which medical and/or surgical decision making was pending. All reviewed examinations had available finalized reports known to the surgical team. RADPEER interradiologist concordance scores were assigned to all reviewed examinations. The impression and plan of the attending surgeon were recorded before and after each in-person review. One hundred patients were reviewed with 11 attending surgeons. The in-person meetings led to changes in surgeons' diagnostic impressions in 43% (43 of 100) and changes in medical and/or surgical planning in 43% (43 of 100; 20 acute changes, 23 nonacute changes, 19 changes in operative management) of cases. There were major discrepancies (RADPEER score ≥3) between the impression of the reviewing radiologist and the written report in 11% of cases (11 of 100). Targeted in-person collaboration between radiologists and acute care surgeons is associated with substantial and frequent changes in patient management, even when the original written report contains all necessary data. The primary mechanism seems to be promotion of a shared mental model that facilitates the exchange of complex information. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Personal and Network Dynamics in Performance of Knowledge Workers: A Study of Australian Breast Radiologists.

Directory of Open Access Journals (Sweden)

Seyedamir Tavakoli Taba

Full Text Available In this paper, we propose a theoretical model based upon previous studies about personal and social network dynamics of job performance. We provide empirical support for this model using real-world data within the context of the Australian radiology profession. An examination of radiologists' professional network topology through structural-positional and relational dimensions and radiologists' personal characteristics in terms of knowledge, experience and self-esteem is provided. Thirty one breast imaging radiologists completed a purpose designed questionnaire regarding their network characteristics and personal attributes. These radiologists also independently read a test set of 60 mammographic cases: 20 cases with cancer and 40 normal cases. A Jackknife free response operating characteristic (JAFROC method was used to measure the performance of the radiologists' in detecting breast cancers.Correlational analyses showed that reader performance was positively correlated with the social network variables of degree centrality and effective size, but negatively correlated with constraint and hierarchy. For personal characteristics, the number of mammograms read per year and self-esteem (self-evaluation positively correlated with reader performance. Hierarchical multiple regression analysis indicated that the combination of number of mammograms read per year and network's effective size, hierarchy and tie strength was the best fitting model, explaining 63.4% of the variance in reader performance. The results from this study indicate the positive relationship between reading high volumes of cases by radiologists and expertise development, but also strongly emphasise the association between effective social/professional interactions and informal knowledge sharing with high performance.

Dental panoramic tomography: an approach for the general radiologist

International Nuclear Information System (INIS)

Boeddinghaus, R.; Whyte, A.

2006-01-01

Dental panoramic tomography is commonly presented to radiologists with no dental training for interpretation. An overview of the technique, basic anatomy and nomenclature and common pathology is presented with examples to show the anatomy and nomenclature, the artefacts and common pathology

Geographic Distribution of Radiologists and Utilization of Teleradiology in Japan: A Longitudinal Analysis Based on National Census Data.

Science.gov (United States)

Matsumoto, Masatoshi; Koike, Soichi; Kashima, Saori; Awai, Kazuo

2015-01-01

Japan has the most CT and MRI scanners per unit population in the world, and as these technologies spread, their geographic distribution is becoming equalized. In contrast, the number of radiologists per unit population in Japan is the lowest among OECD countries and their geographic distribution is unknown. Likewise, little is known about the use of teleradiology, which can compensate for the uneven distribution of radiologists. Based on the Survey of Physicians, Dentists and Pharmacists and the Static Survey of Medical Institutions by the Ministry of Health, Labour and Welfare, a dataset of radiologists and CT and MRI utilizations in each of Japan's 1811 municipalities was created. The inter-municipality equity of the number of radiologists was evaluated using Gini coefficient. Logistic regression analysis, based on Static Survey data, was performed to evaluate the association between hospital location and teleradiology use. Between 2006 and 2012 the number of radiologists increased by 21.7%, but the Gini coefficient remained unchanged. The number of radiologists per 1,000 CT (MRI) utilizations decreased by 17.9% (1.0%); the number was highest in metropolis and lowest in town/village and the disparity has widened from 1.9 to 2.2 (1.6 to 2.0) times. The number of hospitals and clinics using teleradiology has increased (by 69.6% and 18.1%, respectively). Hospitals located in towns/villages (odds ratio 1.61; 95% confidence interval 1.26-2.07) were more likely to use teleradiology than those in metropolises. Contrary to the CT and MRI distributions, radiologist distribution has not been evened out by the increase in their number; in other words, the distribution of radiologists was not affected by market-derived spatial competition force. As a consequence, the gap of the radiologist shortage between urban and rural areas is increasing. Teleradiology, which is one way to ameliorate this gap, should be encouraged.

Computed tomography angiogram. Accuracy in renal surgery

International Nuclear Information System (INIS)

Rabah, Danny M.; Al-Hathal, Naif; Al-Fuhaid, Turki; Raza, Sayed; Al-Yami, Fahad; Al-Taweel, Waleed; Alomar, Mohamed; Al-Nagshabandi, Nizar

2009-01-01

The objective of this study was to determine the sensitivity and specificity of computed tomography angiogram (CTA) in detecting number and location of renal arteries and veins as well as crossing vessels causing uretero-pelvic junction obstruction (UPJO), and to determine if this can be used in decision-making algorithms for treatment of UPJO. A prospective study was carried out in patients undergoing open, laparoscopic and robotic renal surgery from April 2005 until October 2006. All patients were imaged using CTA with 1.25 collimation of arterial and venous phases. Each multi-detector CTA was then read by one radiologist and his results were compared prospectively with the actual intra-operative findings. Overall, 118 patients were included. CTA had 93% sensitivity, 77% specificity and 90% overall accuracy for detecting a single renal artery, and 76% sensitivity, 92% specificity and 90% overall accuracy for detecting two or more renal arteries (Pearson χ 2 =0.001). There was 95% sensitivity, 84% specificity and 85% overall accuracy for detecting the number of renal veins. CTA had 100% overall accuracy in detecting early dividing renal artery (defined as less than 1.5 cm branching from origin), and 83.3% sensitivity, specificity and overall accuracy in detecting crossing vessels at UPJ. The percentage of surgeons stating CTA to be helpful as pre-operative diagnostic tool was 85%. Computed tomography angiogram is simple, quick and can provide an accurate pre-operative renal vascular anatomy in terms of number and location of renal vessels, early dividing renal arteries and crossing vessels at UPJ. (author)

Cadastral Positioning Accuracy Improvement: a Case Study in Malaysia

Science.gov (United States)

Hashim, N. M.; Omar, A. H.; Omar, K. M.; Abdullah, N. M.; Yatim, M. H. M.

2016-09-01

Cadastral map is a parcel-based information which is specifically designed to define the limitation of boundaries. In Malaysia, the cadastral map is under authority of the Department of Surveying and Mapping Malaysia (DSMM). With the growth of spatial based technology especially Geographical Information System (GIS), DSMM decided to modernize and reform its cadastral legacy datasets by generating an accurate digital based representation of cadastral parcels. These legacy databases usually are derived from paper parcel maps known as certified plan. The cadastral modernization will result in the new cadastral database no longer being based on single and static parcel paper maps, but on a global digital map. Despite the strict process of the cadastral modernization, this reform has raised unexpected queries that remain essential to be addressed. The main focus of this study is to review the issues that have been generated by this transition. The transformed cadastral database should be additionally treated to minimize inherent errors and to fit them to the new satellite based coordinate system with high positional accuracy. This review result will be applied as a foundation for investigation to study the systematic and effectiveness method for Positional Accuracy Improvement (PAI) in cadastral database modernization.

Evaluation and management of patients with peripheral artery disease by interventional radiologists: current practices.

Science.gov (United States)

Prince, Ethan A; Murphy, Timothy P; Dhangana, Raj; Soares, Gregory M; Ahn, Sun H; Dubel, Gregory J

2008-05-01

Traditionally, surgeons have served as primary consultants for patients with peripheral vascular disease for whom revascularization is considered. An important component of care for patients with peripheral artery disease (PAD) is risk factor management. The present study was undertaken to determine current management practices of interventional radiologists for patients with PAD and compare them to published data for vascular surgeons. If PAD patient management practices are similar, this would support direct referral of PAD patients who are considered for revascularization from primary care doctors to interventional radiologists. An online survey was administered to full members of the Society of Interventional Radiology with e-mail addresses on file. Filtering was done to examine and compare interactions among several responses. The margin of error for the survey was +/-2%, based on 95% CIs for the entire surveyed population (N=2,371). Seventy-five percent of respondents see PAD patients in ambulatory office settings. Only eight percent see themselves as the physician responsible for risk factor management, similar to reported results of vascular surgeons (10%). Other variables examined, such as frequency of inquiring about Framingham risk factors, indicate similar practices to those previously reported for vascular surgeons. For interventional radiologists who accept direct referrals for medical management of patients with PAD, disease management by interventional radiologists is similar to that previously reported for vascular surgeons. This supports the role of interventional radiologists who accept direct referrals of patients with PAD as primary consultants to primary care doctors.

Improving the spectral measurement accuracy based on temperature distribution and spectra-temperature relationship

Science.gov (United States)

Li, Zhe; Feng, Jinchao; Liu, Pengyu; Sun, Zhonghua; Li, Gang; Jia, Kebin

2018-05-01

Temperature is usually considered as a fluctuation in near-infrared spectral measurement. Chemometric methods were extensively studied to correct the effect of temperature variations. However, temperature can be considered as a constructive parameter that provides detailed chemical information when systematically changed during the measurement. Our group has researched the relationship between temperature-induced spectral variation (TSVC) and normalized squared temperature. In this study, we focused on the influence of temperature distribution in calibration set. Multi-temperature calibration set selection (MTCS) method was proposed to improve the prediction accuracy by considering the temperature distribution of calibration samples. Furthermore, double-temperature calibration set selection (DTCS) method was proposed based on MTCS method and the relationship between TSVC and normalized squared temperature. We compare the prediction performance of PLS models based on random sampling method and proposed methods. The results from experimental studies showed that the prediction performance was improved by using proposed methods. Therefore, MTCS method and DTCS method will be the alternative methods to improve prediction accuracy in near-infrared spectral measurement.

Regional variation in Medicare payments for medical imaging: radiologists versus nonradiologists.

Science.gov (United States)

Rosman, David A; Nsiah, Eugene; Hughes, Danny R; Duszak, Richard

2015-05-01

The purpose of this article was to study regional variation in Medicare Physician Fee Schedule (MPFS) payments for medical imaging to radiologists compared with nonradiologists. Using a 5% random sample of all Medicare enrollees, which covered approximately 2.5 million Part B beneficiaries in 2011, total professional-only, technical-only, and global MPFS spending was calculated on a state-by-state and United States Census Bureau regional basis for all Medicare Berenson-Eggers Type of Service-defined medical imaging services. Payments to radiologists versus nonradiologists were identified and variation was analyzed. Nationally, mean MPFS medical imaging spending per Medicare beneficiary was $207.17 ($95.71 [46.2%] to radiologists vs $111.46 [53.8%] to nonradiologists). Of professional-only (typically interpretation) payments, 20.6% went to nonradiologists. Of technical-only (typically owned equipment) payments, 84.9% went to nonradiologists. Of global (both professional and technical) payments, 70.1% went to nonradiologists. The percentage of MPFS medical imaging spending on nonradiologists ranged from 32% (Minnesota) to 69.5% (South Carolina). The percentage of MPFS payments for medical imaging to nonradiologists exceeded those to radiologists in 58.8% of states. The relative percentage of MPFS payments to nonradiologists was highest in the South (58.5%) and lowest in the Northeast (48.0%). Nationally, 53.8% of MPFS payments for medical imaging services are made to nonradiologists, who claim a majority of MPFS payments in most states dominated by noninterpretive payments. This majority spending on nonradiologists may have implications in bundled and capitated payment models for radiology services. Medical imaging payment policy initiatives must consider the roles of all provider groups and associated regional variation.

New polymorphic tetranucleotide microsatellites improve scoring accuracy in the bottlenose dolphin Tursiops aduncus

NARCIS (Netherlands)

Nater, Alexander; Kopps, Anna M.; Kruetzen, Michael

We isolated and characterized 19 novel tetranucleotide microsatellite markers in the Indo-Pacific bottlenose dolphin (Tursiops aduncus) in order to improve genotyping accuracy in applications like large-scale population-wide paternity and relatedness assessments. One hundred T. aduncus from Shark

Exploiting Deep Matching and SAR Data for the Geo-Localization Accuracy Improvement of Optical Satellite Images

Directory of Open Access Journals (Sweden)

Nina Merkle

2017-06-01

Full Text Available Improving the geo-localization of optical satellite images is an important pre-processing step for many remote sensing tasks like monitoring by image time series or scene analysis after sudden events. These tasks require geo-referenced and precisely co-registered multi-sensor data. Images captured by the high resolution synthetic aperture radar (SAR satellite TerraSAR-X exhibit an absolute geo-location accuracy within a few decimeters. These images represent therefore a reliable source to improve the geo-location accuracy of optical images, which is in the order of tens of meters. In this paper, a deep learning-based approach for the geo-localization accuracy improvement of optical satellite images through SAR reference data is investigated. Image registration between SAR and optical images requires few, but accurate and reliable matching points. These are derived from a Siamese neural network. The network is trained using TerraSAR-X and PRISM image pairs covering greater urban areas spread over Europe, in order to learn the two-dimensional spatial shifts between optical and SAR image patches. Results confirm that accurate and reliable matching points can be generated with higher matching accuracy and precision with respect to state-of-the-art approaches.

Improvement of User's Accuracy Through Classification of Principal Component Images and Stacked Temporal Images

Institute of Scientific and Technical Information of China (English)

Nilanchal Patel; Brijesh Kumar Kaushal

2010-01-01

The classification accuracy of the various categories on the classified remotely sensed images are usually evaluated by two different measures of accuracy, namely, producer's accuracy (PA) and user's accuracy (UA). The PA of a category indicates to what extent the reference pixels of the category are correctly classified, whereas the UA ora category represents to what extent the other categories are less misclassified into the category in question. Therefore, the UA of the various categories determines the reliability of their interpretation on the classified image and is more important to the analyst than the PA. The present investigation has been performed in order to determine ifthere occurs improvement in the UA of the various categories on the classified image of the principal components of the original bands and on the classified image of the stacked image of two different years. We performed the analyses using the IRS LISS Ⅲ images of two different years, i.e., 1996 and 2009, that represent the different magnitude of urbanization and the stacked image of these two years pertaining to Ranchi area, Jharkhand, India, with a view to assessing the impacts of urbanization on the UA of the different categories. The results of the investigation demonstrated that there occurs significant improvement in the UA of the impervious categories in the classified image of the stacked image, which is attributable to the aggregation of the spectral information from twice the number of bands from two different years. On the other hand, the classified image of the principal components did not show any improvement in the UA as compared to the original images.

Emergencies in radiology: a survey of radiologist and radiology trainees

International Nuclear Information System (INIS)

Craig, Simon; Naidoo, Parmanand

2014-01-01

Emergencies in radiology are infrequent but potentially lethal. Australian and New Zealand radiologists are advised to undergo resuscitation training at least every three years; however, little is known about their experience and confidence in managing common emergencies relevant to their clinical practice. This paper describes the current experience and confidence of radiologists and radiology trainees in Australia and New Zealand in the management of common medical emergencies. A cross-sectional online survey of trainees and fellows of the Royal Australian and New Zealand College of Radiology collected data on training and learning preferences relating to resuscitation and life-support skills, access to emergency medical care, and knowledge, confidence and ability in managing a variety of medical emergencies. There were 602 responses to the survey (response rate 23.4%). The majority of respondents were interested in learning more about the management of contrast reactions, cardiac arrest, ischaemic chest pain and basic life support. Self-rated knowledge, confidence and ability were higher in respondents who had completed life-support training within the previous three years. In this group, however, more than 40% rated their ability at managing contrast reactions as poor or fair, while more than 60% rated their ability as poor or fair for management of cardiac arrest, basic life support, advanced life support and dosing of adrenaline. Preferred resuscitation training modalities included simulation, small-group tutorials and workshops. Self-reported level of skill and expertise in the management of potential emergencies in radiology is suboptimal among a large number of respondents. Consideration should be given to addressing this by improving access to specific training.

Improving decision speed, accuracy and group cohesion through early information gathering in house-hunting ants.

Science.gov (United States)

Stroeymeyt, Nathalie; Giurfa, Martin; Franks, Nigel R

2010-09-29

Successful collective decision-making depends on groups of animals being able to make accurate choices while maintaining group cohesion. However, increasing accuracy and/or cohesion usually decreases decision speed and vice-versa. Such trade-offs are widespread in animal decision-making and result in various decision-making strategies that emphasize either speed or accuracy, depending on the context. Speed-accuracy trade-offs have been the object of many theoretical investigations, but these studies did not consider the possible effects of previous experience and/or knowledge of individuals on such trade-offs. In this study, we investigated how previous knowledge of their environment may affect emigration speed, nest choice and colony cohesion in emigrations of the house-hunting ant Temnothorax albipennis, a collective decision-making process subject to a classical speed-accuracy trade-off. Colonies allowed to explore a high quality nest site for one week before they were forced to emigrate found that nest and accepted it faster than emigrating naïve colonies. This resulted in increased speed in single choice emigrations and higher colony cohesion in binary choice emigrations. Additionally, colonies allowed to explore both high and low quality nest sites for one week prior to emigration remained more cohesive, made more accurate decisions and emigrated faster than emigrating naïve colonies. These results show that colonies gather and store information about available nest sites while their nest is still intact, and later retrieve and use this information when they need to emigrate. This improves colony performance. Early gathering of information for later use is therefore an effective strategy allowing T. albipennis colonies to improve simultaneously all aspects of the decision-making process--i.e. speed, accuracy and cohesion--and partly circumvent the speed-accuracy trade-off classically observed during emigrations. These findings should be taken into account

Diagnostic accuracy of automatic normalization of CBV in glioma grading using T1- weighted DCE-MRI.

Science.gov (United States)

Sahoo, Prativa; Gupta, Rakesh K; Gupta, Pradeep K; Awasthi, Ashish; Pandey, Chandra M; Gupta, Mudit; Patir, Rana; Vaishya, Sandeep; Ahlawat, Sunita; Saha, Indrajit

2017-12-01

Aim of this retrospective study was to compare diagnostic accuracy of proposed automatic normalization method to quantify the relative cerebral blood volume (rCBV) with existing contra-lateral region of interest (ROI) based CBV normalization method for glioma grading using T1-weighted dynamic contrast enhanced MRI (DCE-MRI). Sixty patients with histologically confirmed gliomas were included in this study retrospectively. CBV maps were generated using T1-weighted DCE-MRI and are normalized by contralateral ROI based method (rCBV_contra), unaffected white matter (rCBV_WM) and unaffected gray matter (rCBV_GM), the latter two of these were generated automatically. An expert radiologist with >10years of experience in DCE-MRI and a non-expert with one year experience were used independently to measure rCBVs. Cutoff values for glioma grading were decided from ROC analysis. Agreement of histology with rCBV_WM, rCBV_GM and rCBV_contra respectively was studied using Kappa statistics and intra-class correlation coefficient (ICC). The diagnostic accuracy of glioma grading using the measured rCBV_contra by expert radiologist was found to be high (sensitivity=1.00, specificity=0.96, pnormalization method showed same percentage of agreement for both expert and non-expert user. rCBV_WM showed an agreement of 88.33% (kappa=0.76,pnormalization of CBV using the proposed method could provide better diagnostic accuracy compared to the manual contralateral based approach. Copyright © 2017 Elsevier Inc. All rights reserved.

Hybrid Brain–Computer Interface Techniques for Improved Classification Accuracy and Increased Number of Commands: A Review

Science.gov (United States)

Hong, Keum-Shik; Khan, Muhammad Jawad

2017-01-01

In this article, non-invasive hybrid brain–computer interface (hBCI) technologies for improving classification accuracy and increasing the number of commands are reviewed. Hybridization combining more than two modalities is a new trend in brain imaging and prosthesis control. Electroencephalography (EEG), due to its easy use and fast temporal resolution, is most widely utilized in combination with other brain/non-brain signal acquisition modalities, for instance, functional near infrared spectroscopy (fNIRS), electromyography (EMG), electrooculography (EOG), and eye tracker. Three main purposes of hybridization are to increase the number of control commands, improve classification accuracy and reduce the signal detection time. Currently, such combinations of EEG + fNIRS and EEG + EOG are most commonly employed. Four principal components (i.e., hardware, paradigm, classifiers, and features) relevant to accuracy improvement are discussed. In the case of brain signals, motor imagination/movement tasks are combined with cognitive tasks to increase active brain–computer interface (BCI) accuracy. Active and reactive tasks sometimes are combined: motor imagination with steady-state evoked visual potentials (SSVEP) and motor imagination with P300. In the case of reactive tasks, SSVEP is most widely combined with P300 to increase the number of commands. Passive BCIs, however, are rare. After discussing the hardware and strategies involved in the development of hBCI, the second part examines the approaches used to increase the number of control commands and to enhance classification accuracy. The future prospects and the extension of hBCI in real-time applications for daily life scenarios are provided. PMID:28790910

Hybrid Brain-Computer Interface Techniques for Improved Classification Accuracy and Increased Number of Commands: A Review.

Science.gov (United States)

Hong, Keum-Shik; Khan, Muhammad Jawad

2017-01-01

In this article, non-invasive hybrid brain-computer interface (hBCI) technologies for improving classification accuracy and increasing the number of commands are reviewed. Hybridization combining more than two modalities is a new trend in brain imaging and prosthesis control. Electroencephalography (EEG), due to its easy use and fast temporal resolution, is most widely utilized in combination with other brain/non-brain signal acquisition modalities, for instance, functional near infrared spectroscopy (fNIRS), electromyography (EMG), electrooculography (EOG), and eye tracker. Three main purposes of hybridization are to increase the number of control commands, improve classification accuracy and reduce the signal detection time. Currently, such combinations of EEG + fNIRS and EEG + EOG are most commonly employed. Four principal components (i.e., hardware, paradigm, classifiers, and features) relevant to accuracy improvement are discussed. In the case of brain signals, motor imagination/movement tasks are combined with cognitive tasks to increase active brain-computer interface (BCI) accuracy. Active and reactive tasks sometimes are combined: motor imagination with steady-state evoked visual potentials (SSVEP) and motor imagination with P300. In the case of reactive tasks, SSVEP is most widely combined with P300 to increase the number of commands. Passive BCIs, however, are rare. After discussing the hardware and strategies involved in the development of hBCI, the second part examines the approaches used to increase the number of control commands and to enhance classification accuracy. The future prospects and the extension of hBCI in real-time applications for daily life scenarios are provided.

Hybrid Brain–Computer Interface Techniques for Improved Classification Accuracy and Increased Number of Commands: A Review

Directory of Open Access Journals (Sweden)

Keum-Shik Hong

2017-07-01

Full Text Available In this article, non-invasive hybrid brain–computer interface (hBCI technologies for improving classification accuracy and increasing the number of commands are reviewed. Hybridization combining more than two modalities is a new trend in brain imaging and prosthesis control. Electroencephalography (EEG, due to its easy use and fast temporal resolution, is most widely utilized in combination with other brain/non-brain signal acquisition modalities, for instance, functional near infrared spectroscopy (fNIRS, electromyography (EMG, electrooculography (EOG, and eye tracker. Three main purposes of hybridization are to increase the number of control commands, improve classification accuracy and reduce the signal detection time. Currently, such combinations of EEG + fNIRS and EEG + EOG are most commonly employed. Four principal components (i.e., hardware, paradigm, classifiers, and features relevant to accuracy improvement are discussed. In the case of brain signals, motor imagination/movement tasks are combined with cognitive tasks to increase active brain–computer interface (BCI accuracy. Active and reactive tasks sometimes are combined: motor imagination with steady-state evoked visual potentials (SSVEP and motor imagination with P300. In the case of reactive tasks, SSVEP is most widely combined with P300 to increase the number of commands. Passive BCIs, however, are rare. After discussing the hardware and strategies involved in the development of hBCI, the second part examines the approaches used to increase the number of control commands and to enhance classification accuracy. The future prospects and the extension of hBCI in real-time applications for daily life scenarios are provided.

Double contrast barium enema sensitivity: A comparison of studies by radiographers and radiologists

International Nuclear Information System (INIS)

Culpan, D.G.; Mitchell, A.J.; Hughes, S.; Nutman, M.; Chapman, A.H.

2002-01-01

PURPOSE: A retrospective study of histologically proven cases of colorectal cancer (CRC) was performed to assess whether the sensitivity of the radiographer-performed double contrast barium enema (DCBE) differed from that of the radiologist-performed study. MATERIALS AND METHODS: Histologically proven cases of CRC were reviewed over a 3-year period to ascertain whether: the diagnosis had been made by DCBE in the 3 years before histological diagnosis; the lesion had been correctly diagnosed; the examination had been performed by a radiologist or radiographer. RESULTS: In the 3-year period there were 478 cases with histologically proven CRC. Of these, 239 (50%) had undergone DCBE as the initial radiological investigation of the colon. Sixty-four examinations had been performed by radiographers. A correct diagnosis was made in 58 cases (90.6%), the report was equivocal in one case (1.6%), there were four false-negatives (6.25%), and one case was abandoned (1.6%). One hundred and seventy-five examinations were performed by radiologists. A correct diagnosis was made in 157 cases (89.7%), the report was equivocal in one case (0.6%), there were 16 false-negatives (9.1%), and one case was abandoned (0.6%). CONCLUSION: A sensitivity of 90.6% for radiographer-performed studies compared favourably with 89.7% for radiologist-performed studies and supports the practice of radiographers undertaking barium enemas. Culpan, D.G. et al. (2002)

Indices of agreement between neurosurgeons and a radiologist in interpreting tomography scans in an emergency department.

Science.gov (United States)

Dourado, Jules Carlos; Pereira, Júlio Leonardo Barbosa; Albuquerque, Lucas Alverne Freitas de; Carvalho, Gervásio Teles Cardos de; Dias, Patrícia; Dias, Laura; Bicalho, Marcos; Magalhães, Pollyana; Dellaretti, Marcos

2015-08-01

The power of interpretation in the analysis of cranial computed tomography (CCT) among neurosurgeons and radiologists has rarely been studied. This study aimed to assess the rate of agreement in the interpretation of CCTs between neurosurgeons and a radiologist in an emergency department. 227 CCT were independently analyzed by two neurosurgeons (NS1 and NS2) and a radiologist (RAD). The level of agreement in interpreting the examination was studied. The Kappa values obtained between NS1 and NS2 and RAD were considered nearly perfect and substantial agreement. The highest levels of agreement when evaluating abnormalities were observed in the identification of tumors, hydrocephalus and intracranial hematomas. The worst levels of agreement were observed for leukoaraiosis and reduced brain volume. For diseases in which the emergency room procedure must be determined, agreement in the interpretation of CCTs between the radiologist and neurosurgeons was satisfactory.

Virtual colonoscopy training and accreditation: a national survey of radiologist experience and attitudes in the UK

International Nuclear Information System (INIS)

Burling, D.; Moore, A.; Taylor, S.; La Porte, S.; Marshall, M.

2007-01-01

Aim: Expert consensus recommends directed training and possibly in the future, formal accreditation before independent virtual colonoscopy (VC) reporting. We surveyed radiologists' experience of VC training, compared with barium enema, and assessed attitudes towards accreditation. Materials and methods: A questionnaire was sent to 78 consultant radiologists from 72 centres (65 National Health Service hospitals; seven independent primary screening centres) offering a VC service. Results: Fifty-four (69%) eligible radiologists responded. They had interpreted 18,152 examinations (range 3-1500) in total versus 232,350 (13 times more) barium enemas. Twenty-two (41%) deemed their VC training as inadequate [including five (45%) of screening centre radiologists], and only 14 (26%) had attended a training workshop due to lack of availability (54%) or financial/study leave constraints (24%). Eleven (20%) radiologists routinely double-reported VC examinations versus 37 (69%) barium enemas, yet 21 (39%) considered requirements for VC training were greater than barium enema. Thirty-eight (70%) favoured accreditation beyond internal audit for VC versus 15(28%) for barium enema. Of these 38, seven (18%) favoured 'one-off,' and 18 (47%) periodic testing, with 16 (42%) favouring external audit alone or in combination with testing. Overall, 42 (78%) considered specific accreditation for reporting screening examinations appropriate and 45 (83%) respondents preferred a national radiological organization to regulate such a scheme. Conclusion: There is wide variability in reporting experience and recommendations for VC training have not been widely adopted, in part due to limited access to dedicated workshops. UK radiologists are generally in favour of VC accreditation, governed by a national radiology organization

Chemotherapy Agents: A Primer for the Interventional Radiologist

OpenAIRE

Mihlon, Frank; Ray, Charles E.; Messersmith, Wells

2010-01-01

In this article, the authors review the basic principles of cancer chemotherapy and provide an overview of each of the general classes of chemotherapeutic agents with a target audience of interventional radiologists in mind. Special attention is paid to agents used in regional chemotherapy as well as agents commonly included in systemic chemotherapeutic regimens for patients who also require regional chemotherapy.

CADASTRAL POSITIONING ACCURACY IMPROVEMENT: A CASE STUDY IN MALAYSIA

Directory of Open Access Journals (Sweden)

N. M. Hashim

2016-09-01

Full Text Available Cadastral map is a parcel-based information which is specifically designed to define the limitation of boundaries. In Malaysia, the cadastral map is under authority of the Department of Surveying and Mapping Malaysia (DSMM. With the growth of spatial based technology especially Geographical Information System (GIS, DSMM decided to modernize and reform its cadastral legacy datasets by generating an accurate digital based representation of cadastral parcels. These legacy databases usually are derived from paper parcel maps known as certified plan. The cadastral modernization will result in the new cadastral database no longer being based on single and static parcel paper maps, but on a global digital map. Despite the strict process of the cadastral modernization, this reform has raised unexpected queries that remain essential to be addressed. The main focus of this study is to review the issues that have been generated by this transition. The transformed cadastral database should be additionally treated to minimize inherent errors and to fit them to the new satellite based coordinate system with high positional accuracy. This review result will be applied as a foundation for investigation to study the systematic and effectiveness method for Positional Accuracy Improvement (PAI in cadastral database modernization.

Accuracy Feedback Improves Word Learning from Context: Evidence from a Meaning-Generation Task

Science.gov (United States)

Frishkoff, Gwen A.; Collins-Thompson, Kevyn; Hodges, Leslie; Crossley, Scott

2016-01-01

The present study asked whether accuracy feedback on a meaning generation task would lead to improved contextual word learning (CWL). Active generation can facilitate learning by increasing task engagement and memory retrieval, which strengthens new word representations. However, forced generation results in increased errors, which can be…

Process improvement methods increase the efficiency, accuracy, and utility of a neurocritical care research repository.

Science.gov (United States)

O'Connor, Sydney; Ayres, Alison; Cortellini, Lynelle; Rosand, Jonathan; Rosenthal, Eric; Kimberly, W Taylor

2012-08-01

Reliable and efficient data repositories are essential for the advancement of research in Neurocritical care. Various factors, such as the large volume of patients treated within the neuro ICU, their differing length and complexity of hospital stay, and the substantial amount of desired information can complicate the process of data collection. We adapted the tools of process improvement to the data collection and database design of a research repository for a Neuroscience intensive care unit. By the Shewhart-Deming method, we implemented an iterative approach to improve the process of data collection for each element. After an initial design phase, we re-evaluated all data fields that were challenging or time-consuming to collect. We then applied root-cause analysis to optimize the accuracy and ease of collection, and to determine the most efficient manner of collecting the maximal amount of data. During a 6-month period, we iteratively analyzed the process of data collection for various data elements. For example, the pre-admission medications were found to contain numerous inaccuracies after comparison with a gold standard (sensitivity 71% and specificity 94%). Also, our first method of tracking patient admissions and discharges contained higher than expected errors (sensitivity 94% and specificity 93%). In addition to increasing accuracy, we focused on improving efficiency. Through repeated incremental improvements, we reduced the number of subject records that required daily monitoring from 40 to 6 per day, and decreased daily effort from 4.5 to 1.5 h/day. By applying process improvement methods to the design of a Neuroscience ICU data repository, we achieved a threefold improvement in efficiency and increased accuracy. Although individual barriers to data collection will vary from institution to institution, a focus on process improvement is critical to overcoming these barriers.

Injury of the posterior ligamentous complex of the thoracolumbar spine: a prospective evaluation of the diagnostic accuracy of magnetic resonance imaging.

Science.gov (United States)

Vaccaro, Alexander R; Rihn, Jeffrey A; Saravanja, Davor; Anderson, David G; Hilibrand, Alan S; Albert, Todd J; Fehlings, Michael G; Morrison, William; Flanders, Adam E; France, John C; Arnold, Paul; Anderson, Paul A; Friel, Brian; Malfair, David; Street, John; Kwon, Brian; Paquette, Scott; Boyd, Michael; Dvorak, Marcel F S; Fisher, Charles

2009-11-01

Prospective diagnostic imaging study. To determine the accuracy of magnetic resonance imaging (MRI) in diagnosing injury of the posterior ligamentous complex (PLC) in patients with thoracolumbar trauma. Treatment decisions in thoracolumbar injury patients are currently based on the status of the PLC. It is, therefore, important to understand the accuracy of MRI in diagnosing varying degrees of PLC injury. Prior studies report that MRI is up to 100% sensitive for diagnosing PCL injury. Patients with an acute injury from T1 to L3 who required posterior surgery were prospectively studied. A musculoskeletal radiologist, based on the preoperative MRI findings, characterized each of the 6 components of the PLC as intact, incompletely disrupted, or disrupted. During the surgical procedure, the surgeon identified each component of the PLC as intact, incompletely disrupted, or disrupted. The radiologist's interpretation and surgical findings were compared. Forty-two patients with 62 levels of injury were studied. There were 33 males (78.6%) and 9 females (21.4%), and the average age was 35.7 years. According to the kappa score, there was a moderate level of agreement between the radiologist's interpretation and the intraoperative findings for all PLC components except the thoracolumbar fascia, for which there was slight agreement. The sensitivity for the various PLC components ranged from 79% (left facet capsule) to 90% (interspinous ligament). The specificity ranged from 53% (thoracolumbar fascia) to 65% (ligamentum flavum). There was less agreement between the radiologist and surgeon for the patients with less severe neurologic compromise, i.e., those patients with an AIS grade of either D or E. The sensitivity and specificity of MRI for diagnosing injury of the PLC are lower than previously reported in the literature. The integrity of the PLC as determined by MRI should not be used in isolation to determine treatment.

Evaluation of non-radiologist physicians' knowledge on aspects related to ionizing radiation in imaging

International Nuclear Information System (INIS)

Madrigano, Renata Rodrigues; Abrao, Karen Cristine; Regacini, Rodrigo; Puchnick, Andrea

2014-01-01

Objective: to assess the non-radiologist physicians' knowledge on the use of ionizing radiation in imaging. Materials and Methods: cross-sectional study utilizing an anonymous questionnaire responded by physicians in clinical and surgical specialties, divided into two parts as follows: one including questions about the physicians' characteristics, frequency of imaging studies requests and participation in professional updating events, and another part including multiple choice questions approaching general knowledge about radiation, optimization principles and radioprotection. Results: from a total of 309 questionnaires, 120 (38.8%) were responded, 50% by physicians in surgical specialties and 50% in clinical specialties; respectively 45% and 2.5% of physicians responded that magnetic resonance imaging and ultrasonography use ionizing radiation. Overall, the average grade was higher for surgical specialists with no significant difference, except for the question about exposure in pregnant women (p = 0.047). Physicians who are professionally updated, particularly those attending clinical meetings (p = 0.050) and participating in teaching activities (p = 0.047), showed statistically superior knowledge about ionizing radiation as compared with others. Conclusion: the non-radiologist physicians' is heterogeneous and in some points needs to be improved. Multidisciplinary clinical meetings and teaching activities are important ways to disseminate information on the subject. (author)

Improving the accuracy of acetabular cup implantation using a bulls-eye spirit level.

Science.gov (United States)

Macdonald, Duncan; Gupta, Sanjay; Ohly, Nicholas E; Patil, Sanjeev; Meek, R; Mohammed, Aslam

2011-01-01

Acetabular introducers have a built-in inclination of 45 degrees to the handle shaft. With patients in the lateral position, surgeons aim to align the introducer shaft vertical to the floor to implant the acetabulum at 45 degrees. We aimed to determine if a bulls-eye spirit level attached to an introducer improved the accuracy of implantation. A small circular bulls-eye spirit level was attached to the handle of an acetabular introducer. A saw bone hemipelvis was fixed to a horizontal, flat surface. A cement substitute was placed in the acetabulum and subjects were asked to implant a polyethylene cup, aiming to obtain an angle of inclination of 45 degrees. Two attempts were made with the spirit level masked and two with it unmasked. The distance of the air bubble from the spirit level's center was recorded by a single assessor. The angle of inclination of the acetabular component was then calculated. Subjects included both orthopedic consultants and trainees. Twenty-five subjects completed the study. Accuracy of acetabular implantation when using the unmasked spirit level improved significantly in all grades of surgeon. With the spirit level masked, 12 out of 50 attempts were accurate at 45 degrees inclination; 11 out of 50 attempts were "open," with greater than 45 degrees of inclination, and 27 were "closed," with less than 45 degrees. With the spirit level visible, all subjects achieved an inclination angle of exactly 45 degrees. A simple device attached to the handle of an acetabular introducer can significantly improve the accuracy of implantation of a cemented cup into a saw bone pelvis in the lateral position.

Accuracy improvement of a hybrid robot for ITER application using POE modeling method

International Nuclear Information System (INIS)

Wang, Yongbo; Wu, Huapeng; Handroos, Heikki

2013-01-01

Highlights: ► The product of exponential (POE) formula for error modeling of hybrid robot. ► Differential Evolution (DE) algorithm for parameter identification. ► Simulation results are given to verify the effectiveness of the method. -- Abstract: This paper focuses on the kinematic calibration of a 10 degree-of-freedom (DOF) redundant serial–parallel hybrid robot to improve its accuracy. The robot was designed to perform the assembling and repairing tasks of the vacuum vessel (VV) of the international thermonuclear experimental reactor (ITER). By employing the product of exponentials (POEs) formula, we extended the POE-based calibration method from serial robot to redundant serial–parallel hybrid robot. The proposed method combines the forward and inverse kinematics together to formulate a hybrid calibration method for serial–parallel hybrid robot. Because of the high nonlinear characteristics of the error model and too many error parameters need to be identified, the traditional iterative linear least-square algorithms cannot be used to identify the parameter errors. This paper employs a global optimization algorithm, Differential Evolution (DE), to identify parameter errors by solving the inverse kinematics of the hybrid robot. Furthermore, after the parameter errors were identified, the DE algorithm was adopted to numerically solve the forward kinematics of the hybrid robot to demonstrate the accuracy improvement of the end-effector. Numerical simulations were carried out by generating random parameter errors at the allowed tolerance limit and generating a number of configuration poses in the robot workspace. Simulation of the real experimental conditions shows that the accuracy of the end-effector can be improved to the same precision level of the given external measurement device

Accuracy improvement of a hybrid robot for ITER application using POE modeling method

Energy Technology Data Exchange (ETDEWEB)

Wang, Yongbo, E-mail: yongbo.wang@hotmail.com [Laboratory of Intelligent Machines, Lappeenranta University of Technology, FIN-53851 Lappeenranta (Finland); Wu, Huapeng; Handroos, Heikki [Laboratory of Intelligent Machines, Lappeenranta University of Technology, FIN-53851 Lappeenranta (Finland)

2013-10-15

Highlights: ► The product of exponential (POE) formula for error modeling of hybrid robot. ► Differential Evolution (DE) algorithm for parameter identification. ► Simulation results are given to verify the effectiveness of the method. -- Abstract: This paper focuses on the kinematic calibration of a 10 degree-of-freedom (DOF) redundant serial–parallel hybrid robot to improve its accuracy. The robot was designed to perform the assembling and repairing tasks of the vacuum vessel (VV) of the international thermonuclear experimental reactor (ITER). By employing the product of exponentials (POEs) formula, we extended the POE-based calibration method from serial robot to redundant serial–parallel hybrid robot. The proposed method combines the forward and inverse kinematics together to formulate a hybrid calibration method for serial–parallel hybrid robot. Because of the high nonlinear characteristics of the error model and too many error parameters need to be identified, the traditional iterative linear least-square algorithms cannot be used to identify the parameter errors. This paper employs a global optimization algorithm, Differential Evolution (DE), to identify parameter errors by solving the inverse kinematics of the hybrid robot. Furthermore, after the parameter errors were identified, the DE algorithm was adopted to numerically solve the forward kinematics of the hybrid robot to demonstrate the accuracy improvement of the end-effector. Numerical simulations were carried out by generating random parameter errors at the allowed tolerance limit and generating a number of configuration poses in the robot workspace. Simulation of the real experimental conditions shows that the accuracy of the end-effector can be improved to the same precision level of the given external measurement device.

Hypervascular mediastinal masses: Action points for radiologists

International Nuclear Information System (INIS)

Cabral, Fernanda C.; Trotman-Dickenson, Beatrice; Madan, Rachna

2015-01-01

Highlights: •An algorithm combining clinical data and radiology features of hypervascular mediastinal masses is proposed to determine further evaluation and subsequently guide treatment. •Characteristic features and known association with syndromes and genetic mutations assists in achieving a diagnosis. •MRI and functional imaging can be very helpful in the evaluation of hypervascular mediastinal masses. •Identification of hypervascularity within mediastinal masses should alert the radiologist and clinician and an attempt should be made to preferably avoid percutaneous CT guided biopsies and attempt tissue sampling surgically with better control of post procedure hemorrhage. -- Abstract: Hypervascular mediastinal masses are a distinct group of rare diseases that include a subset of benign and malignant entities. Characteristic features and known association with syndromes and genetic mutations assist in achieving a diagnosis. Imaging allows an understanding of the vascularity of the lesion and should alert the radiologist and clinician to potential hemorrhagic complications and avoid percutaneous CT guided biopsies. In such cases, pre-procedure embolization and surgical biopsy maybe considered for better control of post procedure hemorrhage. The purpose of this article is to describe and illustrate the clinical features and radiologic spectrum of hypervascular mediastinal masses, and discuss the associated clinical and genetic syndromes. We will present an imaging algorithm to determine further evaluation and subsequently guide treatment

Hypervascular mediastinal masses: Action points for radiologists

Energy Technology Data Exchange (ETDEWEB)

Cabral, Fernanda C.; Trotman-Dickenson, Beatrice; Madan, Rachna, E-mail: rmadan@partners.org

2015-03-15

Highlights: •An algorithm combining clinical data and radiology features of hypervascular mediastinal masses is proposed to determine further evaluation and subsequently guide treatment. •Characteristic features and known association with syndromes and genetic mutations assists in achieving a diagnosis. •MRI and functional imaging can be very helpful in the evaluation of hypervascular mediastinal masses. •Identification of hypervascularity within mediastinal masses should alert the radiologist and clinician and an attempt should be made to preferably avoid percutaneous CT guided biopsies and attempt tissue sampling surgically with better control of post procedure hemorrhage. -- Abstract: Hypervascular mediastinal masses are a distinct group of rare diseases that include a subset of benign and malignant entities. Characteristic features and known association with syndromes and genetic mutations assist in achieving a diagnosis. Imaging allows an understanding of the vascularity of the lesion and should alert the radiologist and clinician to potential hemorrhagic complications and avoid percutaneous CT guided biopsies. In such cases, pre-procedure embolization and surgical biopsy maybe considered for better control of post procedure hemorrhage. The purpose of this article is to describe and illustrate the clinical features and radiologic spectrum of hypervascular mediastinal masses, and discuss the associated clinical and genetic syndromes. We will present an imaging algorithm to determine further evaluation and subsequently guide treatment.

A simulated Linear Mixture Model to Improve Classification Accuracy of Satellite Data Utilizing Degradation of Atmospheric Effect

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WIDAD Elmahboub

2005-02-01

Full Text Available Researchers in remote sensing have attempted to increase the accuracy of land cover information extracted from remotely sensed imagery. Factors that influence the supervised and unsupervised classification accuracy are the presence of atmospheric effect and mixed pixel information. A linear mixture simulated model experiment is generated to simulate real world data with known end member spectral sets and class cover proportions (CCP. The CCP were initially generated by a random number generator and normalized to make the sum of the class proportions equal to 1.0 using MATLAB program. Random noise was intentionally added to pixel values using different combinations of noise levels to simulate a real world data set. The atmospheric scattering error is computed for each pixel value for three generated images with SPOT data. Accuracy can either be classified or misclassified. Results portrayed great improvement in classified accuracy, for example, in image 1, misclassified pixels due to atmospheric noise is 41 %. Subsequent to the degradation of atmospheric effect, the misclassified pixels were reduced to 4 %. We can conclude that accuracy of classification can be improved by degradation of atmospheric noise.

Accuracy of the improved quasistatic space-time method checked with experiment

International Nuclear Information System (INIS)

Kugler, G.; Dastur, A.R.

1976-10-01

Recent experiments performed at the Savannah River Laboratory have made it possible to check the accuracy of numerical methods developed to simulate space-dependent neutron transients. The experiments were specifically designed to emphasize delayed neutron holdback. The CERBERUS code using the IQS (Improved Quasistatic) method has been developed to provide a practical yet accurate tool for spatial kinetics calculations of CANDU reactors. The code was tested on the Savannah River experiments and excellent agreement was obtained. (author)

Two Simple Rules for Improving the Accuracy of Empiric Treatment of Multidrug-Resistant Urinary Tract Infections.

Science.gov (United States)

Linsenmeyer, Katherine; Strymish, Judith; Gupta, Kalpana

2015-12-01

The emergence of multidrug-resistant (MDR) uropathogens is making the treatment of urinary tract infections (UTIs) more challenging. We sought to evaluate the accuracy of empiric therapy for MDR UTIs and the utility of prior culture data in improving the accuracy of the therapy chosen. The electronic health records from three U.S. Department of Veterans Affairs facilities were retrospectively reviewed for the treatments used for MDR UTIs over 4 years. An MDR UTI was defined as an infection caused by a uropathogen resistant to three or more classes of drugs and identified by a clinician to require therapy. Previous data on culture results, antimicrobial use, and outcomes were captured from records from inpatient and outpatient settings. Among 126 patient episodes of MDR UTIs, the choices of empiric therapy against the index pathogen were accurate in 66 (52%) episodes. For the 95 patient episodes for which prior microbiologic data were available, when empiric therapy was concordant with the prior microbiologic data, the rate of accuracy of the treatment against the uropathogen improved from 32% to 76% (odds ratio, 6.9; 95% confidence interval, 2.7 to 17.1; P tract (GU)-directed agents (nitrofurantoin or sulfa agents) were equally as likely as broad-spectrum agents to be accurate (P = 0.3). Choosing an agent concordant with previous microbiologic data significantly increased the chance of accuracy of therapy for MDR UTIs, even if the previous uropathogen was a different species. Also, GU-directed or broad-spectrum therapy choices were equally likely to be accurate. The accuracy of empiric therapy could be improved by the use of these simple rules. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Anastomotic leakage after colorectal surgery: diagnostic accuracy of CT

Energy Technology Data Exchange (ETDEWEB)

Kauv, Paul; Benadjaoud, Samir; Boulay-Coletta, Isabelle; Zins, Marc [Fondation Hopital Saint-Joseph, Department of Radiology, Paris (France); Curis, Emmanuel [Universite Paris Descartes, Laboratoire de biomathematiques, Faculte de pharmacie, Paris (France); Loriau, Jerome [Fondation Hopital Saint-Joseph, Department of Digestive Surgery, Paris (France)

2015-12-15

To evaluate the diagnostic accuracy of CT in postoperative colorectal anastomotic leakage (AL). Two independent blinded radiologists reviewed 153 CTs performed for suspected AL within 60 days after surgery in 131 consecutive patients, with (n = 58) or without (n = 95) retrograde contrast enema (RCE). Results were compared to original interpretations. The reference standard was reoperation or consensus (a radiologist and a surgeon) regarding clinical, laboratory, radiological, and follow-up data after medical treatment. AL was confirmed in 34/131 patients. For the two reviewers and original interpretation, sensitivity of CT was 82 %, 87 %, and 71 %, respectively; specificity was 84 %, 84 %, and 92 %. RCE significantly increased the positive predictive value (from 40 % to 88 %, P = 0.0009; 41 % to 92 %, P = 0.0016; and 40 % to 100 %, P = 0.0006). Contrast extravasation was the most sensitive (reviewers, 83 % and 83 %) and specific (97 % and 97 %) sign and was significantly associated with AL by univariate analysis (P < 0.0001 and P < 0.0001). By multivariate analysis with recursive partitioning, CT with RCE was accurate to confirm or rule out AL with contrast extravasation. CT with RCE is accurate for diagnosing postoperative colorectal AL. Contrast extravasation is the most reliable sign. RCE should be performed during CT for suspected AL. (orig.)

Assessment of Volumetric versus Manual Measurement in Disseminated Testicular Cancer; No Difference in Assessment between Non-Radiologists and Genitourinary Radiologist.

Directory of Open Access Journals (Sweden)

Çiğdem Öztürk

Full Text Available The aim of this study was to assess the feasibility and reproducibility of semi-automatic volumetric measurement of retroperitoneal lymph node metastases in testicular cancer (TC patients treated with chemotherapy versus the standardized manual measurements based on RECIST criteria.21 TC patients with retroperitoneal lymph node metastases of testicular cancer were studied with a CT scan of chest and abdomen before and after cisplatin based chemotherapy. Three readers, a surgical resident, a radiological technician and a radiologist, assessed tumor response independently using computerized volumetric analysis with Vitrea software® and manual measurement according to RECIST criteria (version 1.1. Intra- and inter-rater variability were evaluated with intra class correlations and Bland-Altman analysis.Assessment of intra observer and inter observer variance proved non-significant in both measurement modalities. In particularly all intraclass correlation (ICC values for the volumetric analysis were > .99 per observer and between observers. There was minimal bias in agreement for manual as well as volumetric analysis.In this study volumetric measurement using Vitrea software® appears to be a reliable, reproducible method to measure initial tumor volume of retroperitoneal lymph node metastases of testicular cancer after chemotherapy. Both measurement methods can be performed by experienced non-radiologists as well.

Improving decision speed, accuracy and group cohesion through early information gathering in house-hunting ants.

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Nathalie Stroeymeyt

Full Text Available BACKGROUND: Successful collective decision-making depends on groups of animals being able to make accurate choices while maintaining group cohesion. However, increasing accuracy and/or cohesion usually decreases decision speed and vice-versa. Such trade-offs are widespread in animal decision-making and result in various decision-making strategies that emphasize either speed or accuracy, depending on the context. Speed-accuracy trade-offs have been the object of many theoretical investigations, but these studies did not consider the possible effects of previous experience and/or knowledge of individuals on such trade-offs. In this study, we investigated how previous knowledge of their environment may affect emigration speed, nest choice and colony cohesion in emigrations of the house-hunting ant Temnothorax albipennis, a collective decision-making process subject to a classical speed-accuracy trade-off. METHODOLOGY/PRINCIPAL FINDINGS: Colonies allowed to explore a high quality nest site for one week before they were forced to emigrate found that nest and accepted it faster than emigrating naïve colonies. This resulted in increased speed in single choice emigrations and higher colony cohesion in binary choice emigrations. Additionally, colonies allowed to explore both high and low quality nest sites for one week prior to emigration remained more cohesive, made more accurate decisions and emigrated faster than emigrating naïve colonies. CONCLUSIONS/SIGNIFICANCE: These results show that colonies gather and store information about available nest sites while their nest is still intact, and later retrieve and use this information when they need to emigrate. This improves colony performance. Early gathering of information for later use is therefore an effective strategy allowing T. albipennis colonies to improve simultaneously all aspects of the decision-making process--i.e. speed, accuracy and cohesion--and partly circumvent the speed-accuracy trade

Improving the Accuracy of NMR Structures of Large Proteins Using Pseudocontact Shifts as Long-Range Restraints

Energy Technology Data Exchange (ETDEWEB)

Gaponenko, Vadim [National Cancer Institute, Structural Biophysics Laboratory (United States); Sarma, Siddhartha P. [Indian Institute of Science, Molecular Biophysics Unit (India); Altieri, Amanda S. [National Cancer Institute, Structural Biophysics Laboratory (United States); Horita, David A. [Wake Forest University School of Medicine, Department of Biochemistry (United States); Li, Jess; Byrd, R. Andrew [National Cancer Institute, Structural Biophysics Laboratory (United States)], E-mail: rabyrd@ncifcrf.gov

2004-03-15

We demonstrate improved accuracy in protein structure determination for large ({>=}30 kDa), deuterated proteins (e.g. STAT4{sub NT}) via the combination of pseudocontact shifts for amide and methyl protons with the available NOEs in methyl-protonated proteins. The improved accuracy is cross validated by Q-factors determined from residual dipolar couplings measured as a result of magnetic susceptibility alignment. The paramagnet is introduced via binding to thiol-reactive EDTA, and multiple sites can be serially engineered to obtain data from alternative orientations of the paramagnetic anisotropic susceptibility tensor. The technique is advantageous for systems where the target protein has strong interactions with known alignment media.

Selecting fillers on emotional appearance improves lineup identification accuracy.

Science.gov (United States)

Flowe, Heather D; Klatt, Thimna; Colloff, Melissa F

2014-12-01

Mock witnesses sometimes report using criminal stereotypes to identify a face from a lineup, a tendency known as criminal face bias. Faces are perceived as criminal-looking if they appear angry. We tested whether matching the emotional appearance of the fillers to an angry suspect can reduce criminal face bias. In Study 1, mock witnesses (n = 226) viewed lineups in which the suspect had an angry, happy, or neutral expression, and we varied whether the fillers matched the expression. An additional group of participants (n = 59) rated the faces on criminal and emotional appearance. As predicted, mock witnesses tended to identify suspects who appeared angrier and more criminal-looking than the fillers. This tendency was reduced when the lineup fillers matched the emotional appearance of the suspect. Study 2 extended the results, testing whether the emotional appearance of the suspect and fillers affects recognition memory. Participants (n = 1,983) studied faces and took a lineup test in which the emotional appearance of the target and fillers was varied between subjects. Discrimination accuracy was enhanced when the fillers matched an angry target's emotional appearance. We conclude that lineup member emotional appearance plays a critical role in the psychology of lineup identification. The fillers should match an angry suspect's emotional appearance to improve lineup identification accuracy. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Improved precision and accuracy for microarrays using updated probe set definitions

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Larsson Ola

2007-02-01

Full Text Available Abstract Background Microarrays enable high throughput detection of transcript expression levels. Different investigators have recently introduced updated probe set definitions to more accurately map probes to our current knowledge of genes and transcripts. Results We demonstrate that updated probe set definitions provide both better precision and accuracy in probe set estimates compared to the original Affymetrix definitions. We show that the improved precision mainly depends on the increased number of probes that are integrated into each probe set, but we also demonstrate an improvement when the same number of probes is used. Conclusion Updated probe set definitions does not only offer expression levels that are more accurately associated to genes and transcripts but also improvements in the estimated transcript expression levels. These results give support for the use of updated probe set definitions for analysis and meta-analysis of microarray data.

Improving Odometric Accuracy for an Autonomous Electric Cart.

Science.gov (United States)

Toledo, Jonay; Piñeiro, Jose D; Arnay, Rafael; Acosta, Daniel; Acosta, Leopoldo

2018-01-12

In this paper, a study of the odometric system for the autonomous cart Verdino, which is an electric vehicle based on a golf cart, is presented. A mathematical model of the odometric system is derived from cart movement equations, and is used to compute the vehicle position and orientation. The inputs of the system are the odometry encoders, and the model uses the wheels diameter and distance between wheels as parameters. With this model, a least square minimization is made in order to get the nominal best parameters. This model is updated, including a real time wheel diameter measurement improving the accuracy of the results. A neural network model is used in order to learn the odometric model from data. Tests are made using this neural network in several configurations and the results are compared to the mathematical model, showing that the neural network can outperform the first proposed model.

Accuracy improvement in the TDR-based localization of water leaks

Directory of Open Access Journals (Sweden)

Andrea Cataldo

Full Text Available A time domain reflectometry (TDR-based system for the localization of water leaks has been recently developed by the authors. This system, which employs wire-like sensing elements to be installed along the underground pipes, has proven immune to the limitations that affect the traditional, acoustic leak-detection systems.Starting from the positive results obtained thus far, in this work, an improvement of this TDR-based system is proposed. More specifically, the possibility of employing a low-cost, water-absorbing sponge to be placed around the sensing element for enhancing the accuracy in the localization of the leak is addressed.To this purpose, laboratory experiments were carried out mimicking a water leakage condition, and two sensing elements (one embedded in a sponge and one without sponge were comparatively used to identify the position of the leak through TDR measurements. Results showed that, thanks to the water retention capability of the sponge (which maintains the leaked water more localized, the sensing element embedded in the sponge leads to a higher accuracy in the evaluation of the position of the leak. Keywords: Leak localization, TDR, Time domain reflectometry, Water leaks, Underground water pipes

Fluoroscopically guided automated gun biopsy of chest lesions: diagnostic accuracy and complications

International Nuclear Information System (INIS)

Oh, Hee Sul; Han, Young Min; Choi, Ki Chul and others

1998-01-01

To determine the diagnostic accuracy and frequency of complications of fluoroscopyguided transthoracic needle biopsy, using an automated gun biopsy system. We retrospectively reviewed 86 patients who underwent automated gun biopsy between October 1995 and October 1996. An 18-gauge cutting needle was used in all cases. All biopsies were performed under fluoroscopic guidance by one interventional radiologist. Tissue sufficient for histologic diagnosis was obtained in 73 of 86 biopsies(84.9%). Fifty-six lesions were malignent and 30 were benign. Sensitivity and diagnostic accuracy for malignant lesions were 87.5% and 87.5%, respectively while cell type specificity in malignant diagnosis was 91.7%(11/12). Sensitivity and diagnostic accuracy for benign lesions were 80.0% and 73.3%, respectively. Postbioptic pneumothorax occurred in three of 86 biopsies(3.5%), one of which required placement of a chest tube. Automated gun biopsy is a simple, safe method for the diagnosis of focal chest lesions. An automated biopsy device offers high diagnostic accuracy in casis involving malignant and benign lesions of the chest, and is particularly useful for determining malignant cell type and specific diagnosis of benign lesions.=20

Improving the accuracy of energy baseline models for commercial buildings with occupancy data

International Nuclear Information System (INIS)

Liang, Xin; Hong, Tianzhen; Shen, Geoffrey Qiping

2016-01-01

Highlights: • We evaluated several baseline models predicting energy use in buildings. • Including occupancy data improved accuracy of baseline model prediction. • Occupancy is highly correlated with energy use in buildings. • This simple approach can be used in decision makings of energy retrofit projects. - Abstract: More than 80% of energy is consumed during operation phase of a building’s life cycle, so energy efficiency retrofit for existing buildings is considered a promising way to reduce energy use in buildings. The investment strategies of retrofit depend on the ability to quantify energy savings by “measurement and verification” (M&V), which compares actual energy consumption to how much energy would have been used without retrofit (called the “baseline” of energy use). Although numerous models exist for predicting baseline of energy use, a critical limitation is that occupancy has not been included as a variable. However, occupancy rate is essential for energy consumption and was emphasized by previous studies. This study develops a new baseline model which is built upon the Lawrence Berkeley National Laboratory (LBNL) model but includes the use of building occupancy data. The study also proposes metrics to quantify the accuracy of prediction and the impacts of variables. However, the results show that including occupancy data does not significantly improve the accuracy of the baseline model, especially for HVAC load. The reasons are discussed further. In addition, sensitivity analysis is conducted to show the influence of parameters in baseline models. The results from this study can help us understand the influence of occupancy on energy use, improve energy baseline prediction by including the occupancy factor, reduce risks of M&V and facilitate investment strategies of energy efficiency retrofit.

Preoperative Measurement of Tibial Resection in Total Knee Arthroplasty Improves Accuracy of Postoperative Limb Alignment Restoration

Directory of Open Access Journals (Sweden)

Pei-Hui Wu

2016-01-01

Conclusions: Using conventional surgical instruments, preoperative measurement of resection thickness of the tibial plateau on radiographs could improve the accuracy of conventional surgical techniques.

Effect of radiologist experience on the risk of false-positive results in breast cancer screening programs

International Nuclear Information System (INIS)

Zubizarreta Alberdi, Raquel; Llanes, Ana B.F.; Ortega, Raquel Almazan; Exposito, Ruben Roman; Collado, Jose M.V.; Oliveres, Xavier Castells; Queiro Verdes, Teresa; Natal Ramos, Carmen; Sanz, Maria Ederra; Salas Trejo, Dolores

2011-01-01

To evaluate the effect of radiologist experience on the risk of false-positive results in population-based breast cancer screening programmes. We evaluated 1,440,384 single-read screening mammograms, corresponding to 471,112 women aged 45-69 years participating in four Spanish programmes between 1990 and 2006. The mammograms were interpreted by 72 radiologists. The overall percentage of false-positive results was 5.85% and that for false-positives resulting in an invasive procedure was 0.38%. Both the risk of false-positives overall and of false-positives leading to an invasive procedure significantly decreased (p 14,999 mammograms with respect to the reference category (<500). The risk of both categories of false-positives was also significantly reduced (p < 0.001) as radiologists' years of experience increased: OR 0.96 and OR 0.84, respectively, for 1 year's experience and OR 0.72 and OR 0.73, respectively, for more than 4 years' experience with regard to the category of <1 year's experience. Radiologist experience is a determining factor in the risk of a false-positive result in breast cancer screening. (orig.)

Accuracy of MRI diagnosis of internal derangement of the knee in a non-specialized tertiary level referral teaching hospital

International Nuclear Information System (INIS)

Challen, J.; Tang, Y. M.; Stuckey, S.; Hazratwala, K.

2007-01-01

Full text: This study was designed to assess the accuracy of knee MRl examinations carried out in a general tertiary referral hospital without a musculoskeletal fellowship trained radiologist. The study included all patients who had undergone a knee arthroscopy carried out within a 2-year period and who had had a prior MRl knee examination, where both were carried out at this institution. The accuracy of the MRl knee examination was determined by correlation to the arthroscopy report. The accuracy for diagnosis of meniscal and cartilage injuries, in this setting, was found to be similar to a published meta-analysis of previous studies correlating knee MRl and arthroscopy. The overall accuracy of this study was better than the previous similar study. However, the accuracy for diagnosing ACL injuries was lower than in the meta-analysis. The potential reasons for this and other sources of error are discussed

Study on the Accuracy Improvement of the Second-Kind Fredholm Integral Equations by Using the Buffa-Christiansen Functions with MLFMA

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Yue-Qian Wu

2016-01-01

Full Text Available Former works show that the accuracy of the second-kind integral equations can be improved dramatically by using the rotated Buffa-Christiansen (BC functions as the testing functions, and sometimes their accuracy can be even better than the first-kind integral equations. When the rotated BC functions are used as the testing functions, the discretization error of the identity operators involved in the second-kind integral equations can be suppressed significantly. However, the sizes of spherical objects which were analyzed are relatively small. Numerical capability of the method of moments (MoM for solving integral equations with the rotated BC functions is severely limited. Hence, the performance of BC functions for accuracy improvement of electrically large objects is not studied. In this paper, the multilevel fast multipole algorithm (MLFMA is employed to accelerate iterative solution of the magnetic-field integral equation (MFIE. Then a series of numerical experiments are performed to study accuracy improvement of MFIE in perfect electric conductor (PEC cases with the rotated BC as testing functions. Numerical results show that the effect of accuracy improvement by using the rotated BC as the testing functions is greatly different with curvilinear or plane triangular elements but falls off when the size of the object is large.

Toward accountable land use mapping: Using geocomputation to improve classification accuracy and reveal uncertainty

NARCIS (Netherlands)

Beekhuizen, J.; Clarke, K.C.

2010-01-01

The classification of satellite imagery into land use/cover maps is a major challenge in the field of remote sensing. This research aimed at improving the classification accuracy while also revealing uncertain areas by employing a geocomputational approach. We computed numerous land use maps by

Do the terms 'proximal' and 'distal' cause confusion amongst radiologists and other clinicians?

International Nuclear Information System (INIS)

Skillicorn, C.J.

2009-01-01

Aim: To investigate the use of the terms 'proximal' and 'distal', and what respondents think the terms mean, when applied to certain structures within the trunk, notably the veins and the biliary tract. Materials and Methods: Fifty-three respondents were interviewed using simplified anatomical diagrams. Respondents were asked what terms they would use to describe sites at opposite ends of the superior vena cava (SVC), internal jugular vein (IJV), common bile duct (CBD), and pancreatic duct. They were also asked which end of each of these structures they would think was being referred to if they read a radiological report that used these terms. Results: The terms 'proximal' and 'distal' were used by at least 50% of all respondents, and, specifically, at least 60% of radiologists at all four anatomical sites. Eighty-five percent (n = 45) of all respondents and 100% (n = 24) of radiologists agreed that the term 'proximal' CBD referred to its superior end. However, at the other sites there was marked disagreement, 67% (n = 16) of radiologists thought the superior SVC and superior IJV were 'proximal', 33% (n = 8) thought they were 'distal'. There was a 54% (n = 13) to 46% (n = 11) split amongst radiologists as to which end of the pancreatic duct was 'proximal'. Conclusion: The terms 'proximal' and 'distal' are the most frequently used terms to describe positions in veins and the biliary system, but there is widespread confusion about their meaning, which could lead to medical error and ultimately patient harm. The use of alternative terms is advised

Do the terms "proximal" and "distal" cause confusion amongst radiologists and other clinicians?

Science.gov (United States)

Skillicorn, C J

2009-04-01

To investigate the use of the terms "proximal" and "distal", and what respondents think the terms mean, when applied to certain structures within the trunk, notably the veins and the biliary tract. Fifty-three respondents were interviewed using simplified anatomical diagrams. Respondents were asked what terms they would use to describe sites at opposite ends of the superior vena cava (SVC), internal jugular vein (IJV), common bile duct (CBD), and pancreatic duct. They were also asked which end of each of these structures they would think was being referred to if they read a radiological report that used these terms. The terms "proximal" and "distal" were used by at least 50% of all respondents, and, specifically, at least 60% of radiologists at all four anatomical sites. Eighty-five percent (n=45) of all respondents and 100% (n=24) of radiologists agreed that the term "proximal" CBD referred to its superior end. However, at the other sites there was marked disagreement, 67% (n=16) of radiologists thought the superior SVC and superior IJV were "proximal", 33% (n=8) thought they were "distal". There was a 54% (n=13) to 46% (n=11) split amongst radiologists as to which end of the pancreatic duct was "proximal". The terms "proximal" and "distal" are the most frequently used terms to describe positions in veins and the biliary system, but there is widespread confusion about their meaning, which could lead to medical error and ultimately patient harm. The use of alternative terms is advised.

Accuracy Improvement for Light-Emitting-Diode-Based Colorimeter by Iterative Algorithm

Science.gov (United States)

Yang, Pao-Keng

2011-09-01

We present a simple algorithm, combining an interpolating method with an iterative calculation, to enhance the resolution of spectral reflectance by removing the spectral broadening effect due to the finite bandwidth of the light-emitting diode (LED) from it. The proposed algorithm can be used to improve the accuracy of a reflective colorimeter using multicolor LEDs as probing light sources and is also applicable to the case when the probing LEDs have different bandwidths in different spectral ranges, to which the powerful deconvolution method cannot be applied.

Radiologist involvement is associated with reduced use of MRI in the acute period of low back pain in a non-elderly population

International Nuclear Information System (INIS)

Kumamaru, Kanako K.; Sano, Yukiko; Hori, Masaaki; Takamura, Tomohiro; Irie, Ryusuke; Suzuki, Michimasa; Hagiwara, Akifumi; Kamagata, Koji; Nakanishi, Atsushi; Aoki, Shigeki; Kumamaru, Hiraku

2018-01-01

To test the hypothesis that ''acute-period'' lumbar MRI in non-elderly patients with low back pain is less frequently performed at clinics/hospitals with greater involvement of full-time radiologists in the imaging workflow. In a national-level claims database, we identified 14,819 non-elderly patients (mean age: 38.7±8.0 years) who visited clinics/hospitals for low back pain in 2013-2015. We classified the clinics/hospitals into four groups based on the level of full-time radiologist involvement and MRI ownership, and compared the frequency of acute-period lumbar MRI using hierarchical logistic regression analysis. Patients visiting facilities without a full-time radiologist (n=2105) were significantly (p<0.001) more likely to undergo acute-period MRI than those visiting facilities with ≥1 radiologist partially managing imaging workflow (level-1, n=491) or ≥1 radiologist intensively involved in imaging workflow (level-2, n=1190) (15.7% vs. 6.9% and 7.3%; adjusted odds ratio of no-radiologist versus level-2: 2.93, p=0.018). No difference was observed between level-1 and level-2 involvement. Facilities with no full-time radiologist were more likely to perform acute-period MRI to assess for low back pain, while no difference was seen between facilities with varying levels of radiologist involvement in the imaging workflow. Radiologist involvement may contribute to optimal utilisation of medical imaging. (orig.)

Significant improvement of accuracy and precision in the determination of trace rare earths by fluorescence analysis

International Nuclear Information System (INIS)

Ozawa, L.; Hersh, H.N.

1976-01-01

Most of the rare earths in yttrium, gadolinium and lanthanum oxides emit characteristic fluorescent line spectra under irradiation with photons, electrons and x rays. The sensitivity and selectivity of the rare earth fluorescences are high enough to determine the trace amounts (0.01 to 100 ppM) of rare earths. The absolute fluorescent intensities of solids, however, are markedly affected by the synthesis procedure, level of contamination and crystal perfection, resulting in poor accuracy and low precision for the method (larger than 50 percent error). Special care in preparation of the samples is required to obtain good accuracy and precision. It is found that the accuracy and precision for the determination of trace (less than 10 ppM) rare earths by fluorescence analysis improved significantly, while still maintaining the sensitivity, when the determination is made by comparing the ratio of the fluorescent intensities of the trace rare earths to that of a deliberately added rare earth as reference. The variation in the absolute fluorescent intensity remains, but is compensated for by measuring the fluorescent line intensity ratio. Consequently, the determination of trace rare earths (with less than 3 percent error) is easily made by a photoluminescence technique in which the rare earths are excited directly by photons. Accuracy is still maintained when the absolute fluorescent intensity is reduced by 50 percent through contamination by Ni, Fe, Mn or Pb (about 100 ppM). Determination accuracy is also improved for fluorescence analysis by electron excitation and x-ray excitation. For some rare earths, however, accuracy by these techniques is reduced because indirect excitation mechanisms are involved. The excitation mechanisms and the interferences between rare earths are also reported

Occupational burnout among radiographers, sonographers and radiologists in Australia and New Zealand: Findings from a national survey.

Science.gov (United States)

Singh, Nabita; Knight, Kellie; Wright, Caroline; Baird, Marilyn; Akroyd, Duane; Adams, Robert D; Schneider, Michal E

2017-06-01

Evidence demonstrates that health care professionals are more prone to burnout than other professionals due to the emotionally taxing interactions they have with their patients on a daily basis. The aims of this study were to measure occupational burnout levels among sonographers, radiographers and radiologists and to examine predictors of burnout according to demographic characteristics. A cross-sectional online survey was administered in 2010 to radiographers, sonographers and radiologists who were members of the following professional bodies: Australian Institute of Radiography, Australian Sonographers Association and The Royal Australian and New Zealand College of Radiologists. The Maslach Burnout Inventory was used to measure burnout levels for each profession. Data were analysed using SPSS Ver 20 (IBM, Chicago, IL, USA) statistical software. A total of 613 radiographers, 121 sonographers and 35 radiologists participated in the survey. Radiographers, sonographers and radiologists had a high mean (±SD) burnout score for emotional exhaustion (39.9 ± 8.5, 42.2 ± 8.5 and 44.9 ± 7.1 respectively) and depersonalization (18.9 ± 5.5, 20.3 ± 5.8 and 20.6 ± 5.6) compared to MBI norms. Radiographers also had low personal achievement (30.8 ± 5.5) compared to MBI norms. Radiographers and sonographers who were male, worked >10 hours overtime and spent <10% of their time training students per week had significantly higher depersonalization scores (p < 0.05). Burnout levels among radiographers, sonographers and radiologists are high and likely to vary according to some demographic and work-related factors. Further research is needed to examine ways to alleviate burnout in these professions so that loss of experienced staff due to burnout can be minimized and quality of patient care can be maintained. © 2016 The Royal Australian and New Zealand College of Radiologists.

Evaluation of non-radiologist physicians' knowledge on aspects related to ionizing radiation in imaging

Energy Technology Data Exchange (ETDEWEB)

Madrigano, Renata Rodrigues [Hospital Santa Helena, Santo Andre, SP (Brazil); Abrao, Karen Cristine; Regacini, Rodrigo, E-mail: regacini@gmail.com [Universidade Anhembi Morumbi, Sao Paulo, SP (Brazil). Escola de Medicina; Puchnick, Andrea [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina

2014-07-15

Objective: to assess the non-radiologist physicians' knowledge on the use of ionizing radiation in imaging. Materials and Methods: cross-sectional study utilizing an anonymous questionnaire responded by physicians in clinical and surgical specialties, divided into two parts as follows: one including questions about the physicians' characteristics, frequency of imaging studies requests and participation in professional updating events, and another part including multiple choice questions approaching general knowledge about radiation, optimization principles and radioprotection. Results: from a total of 309 questionnaires, 120 (38.8%) were responded, 50% by physicians in surgical specialties and 50% in clinical specialties; respectively 45% and 2.5% of physicians responded that magnetic resonance imaging and ultrasonography use ionizing radiation. Overall, the average grade was higher for surgical specialists with no significant difference, except for the question about exposure in pregnant women (p = 0.047). Physicians who are professionally updated, particularly those attending clinical meetings (p = 0.050) and participating in teaching activities (p = 0.047), showed statistically superior knowledge about ionizing radiation as compared with others. Conclusion: the non-radiologist physicians' is heterogeneous and in some points needs to be improved. Multidisciplinary clinical meetings and teaching activities are important ways to disseminate information on the subject. (author)

Accuracy of chest radiographs in the emergency diagnosis of heart failure

Energy Technology Data Exchange (ETDEWEB)

Studler, Ueli; Kretzschmar, Martin; Steinbrich, Wolfgang [University Hospital Basel, Department of Radiology, Basel (Switzerland); Christ, Michael; Breidthardt, Tobias; Noveanu, Markus; Perruchoud, Andre P.; Mueller, Christian [University Hospital Basel, Department of Internal Medicine, Basel (Switzerland); Schoetzau, Andreas [Institute of Biostatistics, Basel (Switzerland)

2008-08-15

The purpose of this study was to determine the diagnostic accuracy of chest radiographic findings of heart failure (HF) in current patients presenting with dyspnea in the emergency department. In a secondary analysis of the BASEL study, initial chest radiographs of 277 patients with acute dyspnea were evaluated by two radiologists blinded to the adjudicated diagnosis (56% had the final diagnosis of HF). Predefined radiographic criteria of HF were used. Statistical analysis included receiver-operating characteristic (ROC) analysis and calculation of a logistic regression model including B-type natriuretic peptide (BNP) levels. The reader's overall impression showed the highest area under the ROC curve for the diagnosis of HF in both supine and erect patient positions (0.855 and 0.857). Among individual radiographic findings, peribronchial cuffing in the supine position (0.829) showed the highest accuracies. The lowest accuracy was found for the vascular pedicle width in the supine position (0.461). Logistic regression analysis showed no significant differences between the reader's overall impression, the radiographic model, and BNP testing. In our study, the combination of radiographic features provided valuable information and was of comparable accuracy as BNP-testing for the diagnosis of HF. (orig.)

A novel method for improved accuracy of transcription factor binding site prediction

KAUST Repository

Khamis, Abdullah M.; Motwalli, Olaa Amin; Oliva, Romina; Jankovic, Boris R.; Medvedeva, Yulia; Ashoor, Haitham; Essack, Magbubah; Gao, Xin; Bajic, Vladimir B.

2018-01-01

Identifying transcription factor (TF) binding sites (TFBSs) is important in the computational inference of gene regulation. Widely used computational methods of TFBS prediction based on position weight matrices (PWMs) usually have high false positive rates. Moreover, computational studies of transcription regulation in eukaryotes frequently require numerous PWM models of TFBSs due to a large number of TFs involved. To overcome these problems we developed DRAF, a novel method for TFBS prediction that requires only 14 prediction models for 232 human TFs, while at the same time significantly improves prediction accuracy. DRAF models use more features than PWM models, as they combine information from TFBS sequences and physicochemical properties of TF DNA-binding domains into machine learning models. Evaluation of DRAF on 98 human ChIP-seq datasets shows on average 1.54-, 1.96- and 5.19-fold reduction of false positives at the same sensitivities compared to models from HOCOMOCO, TRANSFAC and DeepBind, respectively. This observation suggests that one can efficiently replace the PWM models for TFBS prediction by a small number of DRAF models that significantly improve prediction accuracy. The DRAF method is implemented in a web tool and in a stand-alone software freely available at http://cbrc.kaust.edu.sa/DRAF.

A novel method for improved accuracy of transcription factor binding site prediction

KAUST Repository

Khamis, Abdullah M.

2018-03-20

Identifying transcription factor (TF) binding sites (TFBSs) is important in the computational inference of gene regulation. Widely used computational methods of TFBS prediction based on position weight matrices (PWMs) usually have high false positive rates. Moreover, computational studies of transcription regulation in eukaryotes frequently require numerous PWM models of TFBSs due to a large number of TFs involved. To overcome these problems we developed DRAF, a novel method for TFBS prediction that requires only 14 prediction models for 232 human TFs, while at the same time significantly improves prediction accuracy. DRAF models use more features than PWM models, as they combine information from TFBS sequences and physicochemical properties of TF DNA-binding domains into machine learning models. Evaluation of DRAF on 98 human ChIP-seq datasets shows on average 1.54-, 1.96- and 5.19-fold reduction of false positives at the same sensitivities compared to models from HOCOMOCO, TRANSFAC and DeepBind, respectively. This observation suggests that one can efficiently replace the PWM models for TFBS prediction by a small number of DRAF models that significantly improve prediction accuracy. The DRAF method is implemented in a web tool and in a stand-alone software freely available at http://cbrc.kaust.edu.sa/DRAF.

Diagnosis of venous disorders; A challenge for the radiologist. Die radiologische Diagnostik von Venenerkrankungen; Eine Herausforderung

Energy Technology Data Exchange (ETDEWEB)

Minar, E. (Abt. Angiologie, Universitaetsklinik fuer Innere Medizin 2, Vienna (Austria))

1993-09-01

Limited accuracy in the clinic diagnosis of deep vein thrombosis (VT) makes such diagnostic tests such as duplex sonography or venography necessary. Exact information on the age and extent of the thrombus are necessary for the clinician to optimize the therapeutric management. The correct diagnosis of calf vein thrombosis and of recurrent VT in patients with postphlebitis changes also has implications for treatment. After exclusion of thrombosis, the radiologist should evaluate the leg for other possible causes of symptoms besides VT. Investigation of the venous sytem also has a role in the diagnosis in patients with suspected pulmonary embolism. In patients with chronic venous insuffficiency the deep venous system should assessed for patency and venous valve function. The superficial veins should be differentiated in segments with sufficient or insufficient venous valves, and it is also necessary to look for insufficiency of the perforrating veins. In patients with superficial phlebitis there is risk of propagation into the deep venous system. (orig.)

How well do we prepare pediatric radiologists regarding child abuse? Results of a survey of recently trained fellows

International Nuclear Information System (INIS)

Pennington, Debra J.; Lonergan, Gael J.; Mendelson, Kenneth L.

2004-01-01

Pediatric radiologists serve an important role in the radiologic diagnosis, investigation, and in legal proceedings in cases of child abuse. The Society for Pediatric Radiology should evaluate and insure the adequacy of training of pediatric radiologists for this important role. The Society for Pediatric Radiology Committee on Child Abuse, 2002, conducted a 24-question survey to evaluate the scope and perceived adequacy of training received by pediatric radiology fellows regarding the radiologic diagnosis of child abuse and the associated legal process. Eighty-four surveys were mailed to radiologists who had completed a year in pediatric radiology fellowship training during the years 1999 and 2000. There were 33 surveys returned for an overall response of 39%. Respondents' perception of adequacy of training was best for the radiologic diagnosis of child abuse. The majority perceived they were not well trained in the investigative and legal processes regarding child abuse. The majority would welcome standardized training. Current pediatric radiology training programs do not sufficiently prepare pediatric radiologists for their role in the legal system regarding child abuse. A standardized program to train pediatric radiologists about the imaging diagnosis of child abuse and their role in the legal system is recommended. (orig.)

How well do we prepare pediatric radiologists regarding child abuse? Results of a survey of recently trained fellows

Energy Technology Data Exchange (ETDEWEB)

Pennington, Debra J.; Lonergan, Gael J. [Austin Radiological Association, 6101 West Courtyard Drive, Bldg. 5, TX 78730, Austin (United States); Mendelson, Kenneth L. [South Shore Hospital, Weymouth, Massachusetts (United States)

2004-01-01

Pediatric radiologists serve an important role in the radiologic diagnosis, investigation, and in legal proceedings in cases of child abuse. The Society for Pediatric Radiology should evaluate and insure the adequacy of training of pediatric radiologists for this important role. The Society for Pediatric Radiology Committee on Child Abuse, 2002, conducted a 24-question survey to evaluate the scope and perceived adequacy of training received by pediatric radiology fellows regarding the radiologic diagnosis of child abuse and the associated legal process. Eighty-four surveys were mailed to radiologists who had completed a year in pediatric radiology fellowship training during the years 1999 and 2000. There were 33 surveys returned for an overall response of 39%. Respondents' perception of adequacy of training was best for the radiologic diagnosis of child abuse. The majority perceived they were not well trained in the investigative and legal processes regarding child abuse. The majority would welcome standardized training. Current pediatric radiology training programs do not sufficiently prepare pediatric radiologists for their role in the legal system regarding child abuse. A standardized program to train pediatric radiologists about the imaging diagnosis of child abuse and their role in the legal system is recommended. (orig.)

Lung volume reduction of pulmonary emphysema: the radiologist task.

Science.gov (United States)

Milanese, Gianluca; Silva, Mario; Sverzellati, Nicola

2016-03-01

Several lung volume reduction (LVR) techniques have been increasingly evaluated in patients with advanced pulmonary emphysema, especially in the last decade. Radiologist plays a pivotal role in the characterization of parenchymal damage and, thus, assessment of eligibility criteria. This review aims to discuss the most common LVR techniques, namely LVR surgery, endobronchial valves, and coils LVR, with emphasis on the role of computed tomography (CT). Several trials have recently highlighted the importance of regional quantification of emphysema by computerized CT-based segmentation of hyperlucent parenchyma, which is strongly recommended for candidates to any LVR treatment. In particular, emphysema distribution pattern and fissures integrity are evaluated to tailor the choice of the most appropriate LVR technique. Furthermore, a number of CT measures have been tested for the personalization of treatment, according to imaging detected heterogeneity of parenchymal disease. CT characterization of heterogeneous parenchymal abnormalities provides criteria for selection of the preferable treatment in each patient and improves outcome of LVR as reflected by better quality of life, higher exercise tolerance, and lower mortality.

Improving Odometric Accuracy for an Autonomous Electric Cart

Directory of Open Access Journals (Sweden)

Jonay Toledo

2018-01-01

Full Text Available In this paper, a study of the odometric system for the autonomous cart Verdino, which is an electric vehicle based on a golf cart, is presented. A mathematical model of the odometric system is derived from cart movement equations, and is used to compute the vehicle position and orientation. The inputs of the system are the odometry encoders, and the model uses the wheels diameter and distance between wheels as parameters. With this model, a least square minimization is made in order to get the nominal best parameters. This model is updated, including a real time wheel diameter measurement improving the accuracy of the results. A neural network model is used in order to learn the odometric model from data. Tests are made using this neural network in several configurations and the results are compared to the mathematical model, showing that the neural network can outperform the first proposed model.

Abdominal and pelvic computed tomography (CT) interpretation: discrepancy rates among experienced radiologists

Energy Technology Data Exchange (ETDEWEB)

Abujudeh, Hani H.; Boland, Giles W.; Kaewlai, Rathachai; Rabiner, Pavel; Thrall, James H. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Halpern, Elkarn F.; Gazelle, G.S. [Massachusetts General Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States); Massachusetts General Hospital and Harvard Medical School, Institute for Technology Assessment, Boston, MA (United States)

2010-08-15

To assess the discrepancy rate for the interpretation of abdominal and pelvic computed tomography (CT) examinations among experienced radiologists. Ninety abdominal and pelvic CT examinations reported by three experienced radiologists who specialize in abdominal imaging were randomly selected from the radiological database. The same radiologists, blinded to previous interpretation, were asked to re-interpret 60 examinations: 30 of their previous interpretations and 30 interpreted by others. All reports were assessed for the degree of discrepancy between initial and repeat interpretations according to a three-level scoring system: no discrepancy, minor, or major discrepancy. Inter- and intrareader discrepancy rates and causes were evaluated. CT examinations included in the investigation were performed on 90 patients (43 men, mean age 59 years, SD 14, range 19-88) for the following indications: follow-up/evaluation of malignancy (69/90, 77%), pancreatitis (5/90, 6%), urinary tract stone (4/90, 4%) or other (12/90, 13%). Interobserver and intraobserver major discrepancy rates were 26 and 32%, respectively. Major discrepancies were due to missed findings, different opinions regarding interval change of clinically significant findings, and the presence of recommendation. Major discrepancy of between 26 and 32% was observed in the interpretation of abdominal and pelvic CT examinations. (orig.)

Abdominal and pelvic computed tomography (CT) interpretation: discrepancy rates among experienced radiologists

International Nuclear Information System (INIS)

Abujudeh, Hani H.; Boland, Giles W.; Kaewlai, Rathachai; Rabiner, Pavel; Thrall, James H.; Halpern, Elkarn F.; Gazelle, G.S.

2010-01-01

To assess the discrepancy rate for the interpretation of abdominal and pelvic computed tomography (CT) examinations among experienced radiologists. Ninety abdominal and pelvic CT examinations reported by three experienced radiologists who specialize in abdominal imaging were randomly selected from the radiological database. The same radiologists, blinded to previous interpretation, were asked to re-interpret 60 examinations: 30 of their previous interpretations and 30 interpreted by others. All reports were assessed for the degree of discrepancy between initial and repeat interpretations according to a three-level scoring system: no discrepancy, minor, or major discrepancy. Inter- and intrareader discrepancy rates and causes were evaluated. CT examinations included in the investigation were performed on 90 patients (43 men, mean age 59 years, SD 14, range 19-88) for the following indications: follow-up/evaluation of malignancy (69/90, 77%), pancreatitis (5/90, 6%), urinary tract stone (4/90, 4%) or other (12/90, 13%). Interobserver and intraobserver major discrepancy rates were 26 and 32%, respectively. Major discrepancies were due to missed findings, different opinions regarding interval change of clinically significant findings, and the presence of recommendation. Major discrepancy of between 26 and 32% was observed in the interpretation of abdominal and pelvic CT examinations. (orig.)

Improvement of Measurement Accuracy of Coolant Flow in a Test Loop

Energy Technology Data Exchange (ETDEWEB)

Hong, Jintae; Kim, Jong-Bum; Joung, Chang-Young; Ahn, Sung-Ho; Heo, Sung-Ho; Jang, Seoyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

In this study, to improve the measurement accuracy of coolant flow in a coolant flow simulator, elimination of external noise are enhanced by adding ground pattern in the control panel and earth around signal cables. In addition, a heating unit is added to strengthen the fluctuation signal by heating the coolant because the source of signals are heat energy. Experimental results using the improved system shows good agreement with the reference flow rate. The measurement error is reduced dramatically compared with the previous measurement accuracy and it will help to analyze the performance of nuclear fuels. For further works, out of pile test will be carried out by fabricating a test rig mockup and inspect the feasibility of the developed system. To verify the performance of a newly developed nuclear fuel, irradiation test needs to be carried out in the research reactor and measure the irradiation behavior such as fuel temperature, fission gas release, neutron dose, coolant temperature, and coolant flow rate. In particular, the heat generation rate of nuclear fuels can be measured indirectly by measuring temperature variation of coolant which passes by the fuel rod and its flow rate. However, it is very difficult to measure the flow rate of coolant at the fuel rod owing to the narrow gap between components of the test rig. In nuclear fields, noise analysis using thermocouples in the test rig has been applied to measure the flow velocity of coolant which circulates through the test loop.

Improving calibration accuracy in gel dosimetry

International Nuclear Information System (INIS)

Oldham, M.; McJury, M.; Webb, S.; Baustert, I.B.; Leach, M.O.

1998-01-01

A new method of calibrating gel dosimeters (applicable to both Fricke and polyacrylamide gels) is presented which has intrinsically higher accuracy than current methods, and requires less gel. Two test-tubes of gel (inner diameter 2.5 cm, length 20 cm) are irradiated separately with a 10x10cm 2 field end-on in a water bath, such that the characteristic depth-dose curve is recorded in the gel. The calibration is then determined by fitting the depth-dose measured in water, against the measured change in relaxivity with depth in the gel. Increased accuracy is achieved in this simple depth-dose geometry by averaging the relaxivity at each depth. A large number of calibration data points, each with relatively high accuracy, are obtained. Calibration data over the full range of dose (1.6-10 Gy) is obtained by irradiating one test-tube to 10 Gy at dose maximum (D max ), and the other to 4.5 Gy at D max . The new calibration method is compared with a 'standard method' where five identical test-tubes of gel were irradiated to different known doses between 2 and 10 Gy. The percentage uncertainties in the slope and intercept of the calibration fit are found to be lower with the new method by a factor of about 4 and 10 respectively, when compared with the standard method and with published values. The gel was found to respond linearly within the error bars up to doses of 7 Gy, with a slope of 0.233±0.001 s -1 Gy -1 and an intercept of 1.106±0.005 Gy. For higher doses, nonlinear behaviour was observed. (author)

The causes of medical malpractice suits against radiologists in the United States.

Science.gov (United States)

Whang, Jeremy S; Baker, Stephen R; Patel, Ronak; Luk, Lyndon; Castro, Alejandro

2013-02-01

To determine the most frequent causes of malpractice suits as derived from credentialing data of 8401 radiologists. This study was approved by the Institutional Review Board of New Jersey Medical School. A total of 8401 radiologists in 47 states participating in the network of One-Call Medical, a broker for computed tomographic/magnetic resonance studies in workers' compensation cases, were required to provide their malpractice history as part of their credentialing application. Of these, 2624 (31%) radiologists had at least one claim in their career. In each enrollee's credentialing file, if there was a claim against the enrollee there was a narrative regarding each malpractice case from which, in most instances, a primary allegation could be discerned. Among the 4793 cases, an alleged cause could be derived from the narrative in 4043 (84%). Statistical analysis was performed with Stata 12 (2011; Stata, College Station, Tex) software. The most common general cause was error in diagnosis (14.83 claims per 1000 person-years [95% confidence interval {CI}: 14.19, 15.51]). In this category, breast cancer was the most frequently missed diagnosis (3.57 claims per 1000 person-years [95% CI: 3.26, 3.91]), followed by nonspinal fractures (2.49 claims per 1000 person-years [95% CI: 2.28, 2.72]), spinal fractures (1.32 claims per 1000 person-years [95% CI: 1.16, 1.49]), lung cancer (1.26 claims per 1000 person-years [95% CI: 1.11, 1.42]), and vascular disease (1.08 claims per 1000 person-years [95% CI: 0.93, 1.24]). The category next in frequency was procedural complications (1.76 claims per 1000 person-years [95% CI: 1.58, 1.96]), followed by inadequate communication with either patient (0.40 claim per 1000 person-years [95% CI: 0.32, 0.50]) or referrer (0.71 claim per 1000 person-years [95% CI: 0.60, 0.84]). Radiologists had only a peripheral role in 0.92 claim per 1000 person-years (95% CI: 0.77, 1.10). Failure to recommend additional testing was a rare cause (0.41 claim

Improvement of Accuracy for Background Noise Estimation Method Based on TPE-AE

Science.gov (United States)

Itai, Akitoshi; Yasukawa, Hiroshi

This paper proposes a method of a background noise estimation based on the tensor product expansion with a median and a Monte carlo simulation. We have shown that a tensor product expansion with absolute error method is effective to estimate a background noise, however, a background noise might not be estimated by using conventional method properly. In this paper, it is shown that the estimate accuracy can be improved by using proposed methods.

Improving Accuracy of Dempster-Shafer Theory Based Anomaly Detection Systems

Directory of Open Access Journals (Sweden)

Ling Zou

2014-07-01

Full Text Available While the Dempster-Shafer theory of evidence has been widely used in anomaly detection, there are some issues with them. Dempster-Shafer theory of evidence trusts evidences equally which does not hold in distributed-sensor ADS. Moreover, evidences are dependent with each other sometimes which will lead to false alert. We propose improving by incorporating two algorithms. Features selection algorithm employs Gaussian Graphical Models to discover correlation between some candidate features. A group of suitable ADS were selected to detect and detection result were send to the fusion engine. Information gain is applied to set weight for every feature on Weights estimated algorithm. A weighted Dempster-Shafer theory of evidence combined the detection results to achieve a better accuracy. We evaluate our detection prototype through a set of experiments that were conducted with standard benchmark Wisconsin Breast Cancer Dataset and real Internet traffic. Evaluations on the Wisconsin Breast Cancer Dataset show that our prototype can find the correlation in nine features and improve the detection rate without affecting the false positive rate. Evaluations on Internet traffic show that Weights estimated algorithm can improve the detection performance significantly.

Radiologists' Usage of Social Media : Results of the RANSOM Survey

NARCIS (Netherlands)

Ranschaert, Erik R.; Van Ooijen, Peter M. A.; McGinty, Geraldine B.; Parizel, Paul M.

The growing use of social media is transforming the way health care professionals (HCPs) are communicating. In this changing environment, it could be useful to outline the usage of social media by radiologists in all its facets and on an international level. The main objective of the RANSOM survey

Computer hardware for radiologists: Part 2

International Nuclear Information System (INIS)

Indrajit, IK; Alam, A

2010-01-01

Computers are an integral part of modern radiology equipment. In the first half of this two-part article, we dwelt upon some fundamental concepts regarding computer hardware, covering components like motherboard, central processing unit (CPU), chipset, random access memory (RAM), and memory modules. In this article, we describe the remaining computer hardware components that are of relevance to radiology. “Storage drive” is a term describing a “memory” hardware used to store data for later retrieval. Commonly used storage drives are hard drives, floppy drives, optical drives, flash drives, and network drives. The capacity of a hard drive is dependent on many factors, including the number of disk sides, number of tracks per side, number of sectors on each track, and the amount of data that can be stored in each sector. “Drive interfaces” connect hard drives and optical drives to a computer. The connections of such drives require both a power cable and a data cable. The four most popular “input/output devices” used commonly with computers are the printer, monitor, mouse, and keyboard. The “bus” is a built-in electronic signal pathway in the motherboard to permit efficient and uninterrupted data transfer. A motherboard can have several buses, including the system bus, the PCI express bus, the PCI bus, the AGP bus, and the (outdated) ISA bus. “Ports” are the location at which external devices are connected to a computer motherboard. All commonly used peripheral devices, such as printers, scanners, and portable drives, need ports. A working knowledge of computers is necessary for the radiologist if the workflow is to realize its full potential and, besides, this knowledge will prepare the radiologist for the coming innovations in the ‘ever increasing’ digital future

Computer hardware for radiologists: Part 2

Directory of Open Access Journals (Sweden)

Indrajit I

2010-01-01

Full Text Available Computers are an integral part of modern radiology equipment. In the first half of this two-part article, we dwelt upon some fundamental concepts regarding computer hardware, covering components like motherboard, central processing unit (CPU, chipset, random access memory (RAM, and memory modules. In this article, we describe the remaining computer hardware components that are of relevance to radiology. "Storage drive" is a term describing a "memory" hardware used to store data for later retrieval. Commonly used storage drives are hard drives, floppy drives, optical drives, flash drives, and network drives. The capacity of a hard drive is dependent on many factors, including the number of disk sides, number of tracks per side, number of sectors on each track, and the amount of data that can be stored in each sector. "Drive interfaces" connect hard drives and optical drives to a computer. The connections of such drives require both a power cable and a data cable. The four most popular "input/output devices" used commonly with computers are the printer, monitor, mouse, and keyboard. The "bus" is a built-in electronic signal pathway in the motherboard to permit efficient and uninterrupted data transfer. A motherboard can have several buses, including the system bus, the PCI express bus, the PCI bus, the AGP bus, and the (outdated ISA bus. "Ports" are the location at which external devices are connected to a computer motherboard. All commonly used peripheral devices, such as printers, scanners, and portable drives, need ports. A working knowledge of computers is necessary for the radiologist if the workflow is to realize its full potential and, besides, this knowledge will prepare the radiologist for the coming innovations in the ′ever increasing′ digital future.

Improving ASTER GDEM Accuracy Using Land Use-Based Linear Regression Methods: A Case Study of Lianyungang, East China

Directory of Open Access Journals (Sweden)

Xiaoyan Yang

2018-04-01

Full Text Available The Advanced Spaceborne Thermal-Emission and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM is important to a wide range of geographical and environmental studies. Its accuracy, to some extent associated with land-use types reflecting topography, vegetation coverage, and human activities, impacts the results and conclusions of these studies. In order to improve the accuracy of ASTER GDEM prior to its application, we investigated ASTER GDEM errors based on individual land-use types and proposed two linear regression calibration methods, one considering only land use-specific errors and the other considering the impact of both land-use and topography. Our calibration methods were tested on the coastal prefectural city of Lianyungang in eastern China. Results indicate that (1 ASTER GDEM is highly accurate for rice, wheat, grass and mining lands but less accurate for scenic, garden, wood and bare lands; (2 despite improvements in ASTER GDEM2 accuracy, multiple linear regression calibration requires more data (topography and a relatively complex calibration process; (3 simple linear regression calibration proves a practicable and simplified means to systematically investigate and improve the impact of land-use on ASTER GDEM accuracy. Our method is applicable to areas with detailed land-use data based on highly accurate field-based point-elevation measurements.

A Method for Improving the Pose Accuracy of a Robot Manipulator Based on Multi-Sensor Combined Measurement and Data Fusion

Science.gov (United States)

Liu, Bailing; Zhang, Fumin; Qu, Xinghua

2015-01-01

An improvement method for the pose accuracy of a robot manipulator by using a multiple-sensor combination measuring system (MCMS) is presented. It is composed of a visual sensor, an angle sensor and a series robot. The visual sensor is utilized to measure the position of the manipulator in real time, and the angle sensor is rigidly attached to the manipulator to obtain its orientation. Due to the higher accuracy of the multi-sensor, two efficient data fusion approaches, the Kalman filter (KF) and multi-sensor optimal information fusion algorithm (MOIFA), are used to fuse the position and orientation of the manipulator. The simulation and experimental results show that the pose accuracy of the robot manipulator is improved dramatically by 38%∼78% with the multi-sensor data fusion. Comparing with reported pose accuracy improvement methods, the primary advantage of this method is that it does not require the complex solution of the kinematics parameter equations, increase of the motion constraints and the complicated procedures of the traditional vision-based methods. It makes the robot processing more autonomous and accurate. To improve the reliability and accuracy of the pose measurements of MCMS, the visual sensor repeatability is experimentally studied. An optimal range of 1 × 0.8 × 1 ∼ 2 × 0.8 × 1 m in the field of view (FOV) is indicated by the experimental results. PMID:25850067

Effects of Different Compression Techniques on Diagnostic Accuracies of Breast Masses on Digitized Mammograms

International Nuclear Information System (INIS)

Zhigang Liang; Xiangying Du; Jiabin Liu; Yanhui Yang; Dongdong Rong; Xinyu Y ao; Kuncheng Li

2008-01-01

Background: The JPEG 2000 compression technique has recently been introduced into the medical imaging field. It is critical to understand the effects of this technique on the detection of breast masses on digitized images by human observers. Purpose: To evaluate whether lossless and lossy techniques affect the diagnostic results of malignant and benign breast masses on digitized mammograms. Material and Methods: A total of 90 screen-film mammograms including craniocaudal and lateral views obtained from 45 patients were selected by two non-observing radiologists. Of these, 22 cases were benign lesions and 23 cases were malignant. The mammographic films were digitized by a laser film digitizer, and compressed to three levels (lossless and lossy 20:1 and 40:1) using the JPEG 2000 wavelet-based image compression algorithm. Four radiologists with 10-12 years' experience in mammography interpreted the original and compressed images. The time interval was 3 weeks for each reading session. A five-point malignancy scale was used, with a score of 1 corresponding to definitely not a malignant mass, a score of 2 referring to not a malignant mass, a score of 3 meaning possibly a malignant mass, a score of 4 being probably a malignant mass, and a score of 5 interpreted as definitely a malignant mass. The radiologists' performance was evaluated using receiver operating characteristic analysis. Results: The average Az values for all radiologists decreased from 0.8933 for the original uncompressed images to 0.8299 for the images compressed at 40:1. This difference was not statistically significant. The detection accuracy of the original images was better than that of the compressed images, and the Az values decreased with increasing compression ratio. Conclusion: Digitized mammograms compressed at 40:1 could be used to substitute original images in the diagnosis of breast cancer

Improving the Stability and Accuracy of Power Hardware-in-the-Loop Simulation Using Virtual Impedance Method

Directory of Open Access Journals (Sweden)

Xiaoming Zha

2016-11-01

Full Text Available Power hardware-in-the-loop (PHIL systems are advanced, real-time platforms for combined software and hardware testing. Two paramount issues in PHIL simulations are the closed-loop stability and simulation accuracy. This paper presents a virtual impedance (VI method for PHIL simulations that improves the simulation’s stability and accuracy. Through the establishment of an impedance model for a PHIL simulation circuit, which is composed of a voltage-source converter and a simple network, the stability and accuracy of the PHIL system are analyzed. Then, the proposed VI method is implemented in a digital real-time simulator and used to correct the combined impedance in the impedance model, achieving higher stability and accuracy of the results. The validity of the VI method is verified through the PHIL simulation of two typical PHIL examples.

Overlay accuracy fundamentals

Science.gov (United States)

Kandel, Daniel; Levinski, Vladimir; Sapiens, Noam; Cohen, Guy; Amit, Eran; Klein, Dana; Vakshtein, Irina

2012-03-01

Currently, the performance of overlay metrology is evaluated mainly based on random error contributions such as precision and TIS variability. With the expected shrinkage of the overlay metrology budget to DBO (1st order diffraction based overlay). It is demonstrated that the sensitivity of DBO to overlay mark asymmetry is larger than the sensitivity of imaging overlay. Finally, we show that a recently developed measurement quality metric serves as a valuable tool for improving overlay metrology accuracy. Simulation results demonstrate that the accuracy of imaging overlay can be improved significantly by recipe setup optimized using the quality metric. We conclude that imaging overlay metrology, complemented by appropriate use of measurement quality metric, results in optimal overlay accuracy.

Incidental abdominopelvic findings on expanded field-of-view lumbar spinal MRI: frequency, clinical importance, and concordance in interpretation by neuroimaging and body imaging radiologists

International Nuclear Information System (INIS)

Maxwell, A.W.P.; Keating, D.P.; Nickerson, J.P.

2015-01-01

Aim: To characterize the frequency of identification, clinical importance, and concordance in interpretation of incidental abdominopelvic findings identified on routine lumbar spinal MRI using supplemental expanded field-of-view (FOV) coronal imaging. Materials and methods: All lumbar spinal MRI reports over a 12-month period were retrospectively reviewed for the presence of incidental abdominopelvic findings identified using expanded FOV coronal imaging. Medical records were used to identify those findings that received follow-up, which were then categorized according to final diagnosis and classified as “indeterminate,” “likely clinically unimportant,” and “likely clinically important”. All cases that received follow-up were blindly and independently re-reviewed by a neuroimaging radiologist and body-imaging radiologist, and reviewer performances were compared to assess for agreement with regard to lesion significance, need for follow-up, and other parameters. Results: In total, 2067 reports were reviewed: 687 (33.2%) featured one or more incidental abdominopelvic findings, and 102 (4.9%) findings received further evaluation. Of these, 11 (10.9%) were classified as “indeterminate,” 50 (49%) as “likely clinically unimportant,” and 41 (40.1%) were classified as “likely clinically important.” Excellent agreement was observed between the reviewing radiologists for all evaluated parameters. Conclusion: The addition of an expanded FOV coronal sequence to the standard lumbar spinal MRI protocol was associated with the identification of a large number of incidental abdominopelvic findings, the minority of which represent likely clinically important findings. Most incidental findings were confidently dismissed by a neuroimaging radiologist as likely clinically unimportant without utilization of additional clinical or radiographic resources. - Highlights: • Expanded field-of-view (FOV) MRI improves detection of important incidental findings. �

Breast Density Estimation with Fully Automated Volumetric Method: Comparison to Radiologists' Assessment by BI-RADS Categories.

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Singh, Tulika; Sharma, Madhurima; Singla, Veenu; Khandelwal, Niranjan

2016-01-01

The objective of our study was to calculate mammographic breast density with a fully automated volumetric breast density measurement method and to compare it to breast imaging reporting and data system (BI-RADS) breast density categories assigned by two radiologists. A total of 476 full-field digital mammography examinations with standard mediolateral oblique and craniocaudal views were evaluated by two blinded radiologists and BI-RADS density categories were assigned. Using a fully automated software, mean fibroglandular tissue volume, mean breast volume, and mean volumetric breast density were calculated. Based on percentage volumetric breast density, a volumetric density grade was assigned from 1 to 4. The weighted overall kappa was 0.895 (almost perfect agreement) for the two radiologists' BI-RADS density estimates. A statistically significant difference was seen in mean volumetric breast density among the BI-RADS density categories. With increased BI-RADS density category, increase in mean volumetric breast density was also seen (P BI-RADS categories and volumetric density grading by fully automated software (ρ = 0.728, P BI-RADS density category by two observers showed fair agreement (κ = 0.398 and 0.388, respectively). In our study, a good correlation was seen between density grading using fully automated volumetric method and density grading using BI-RADS density categories assigned by the two radiologists. Thus, the fully automated volumetric method may be used to quantify breast density on routine mammography. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Radiation exposure of radiologists during angiography: Dose measurements outside the lead apron

International Nuclear Information System (INIS)

Fischer, H.; Przetak, C.; Teubert, G.; Ewen, K.; Moedder, U.

1995-01-01

The aim of this study was to provide practical information to angiographers concerning radiation exposure to body parts not covered by lead aprons. Individual doses to the neck and hands of radiologists measured in micro-Sieverts were obtained during the course of 80 angiographies of various types. The number of diagnostic and interventional procedures, which might lead to exceeding permissible doses, have been calculated. Possibilities of estimating doses during angiography by means of parameters such as screening times were examined statistically. Especially with regard to the hands, estimations of the doses are insufficient (correlation r=0.21). Radiologists who undertake much angiographic and particularly interventional work may reach exposure levels requiring protective measures in addition to lead aprons. (orig.) [de

Effects of accuracy motivation and anchoring on metacomprehension judgment and accuracy.

Science.gov (United States)

Zhao, Qin

2012-01-01

The current research investigates how accuracy motivation impacts anchoring and adjustment in metacomprehension judgment and how accuracy motivation and anchoring affect metacomprehension accuracy. Participants were randomly assigned to one of six conditions produced by the between-subjects factorial design involving accuracy motivation (incentive or no) and peer performance anchor (95%, 55%, or no). Two studies showed that accuracy motivation did not impact anchoring bias, but the adjustment-from-anchor process occurred. Accuracy incentive increased anchor-judgment gap for the 95% anchor but not for the 55% anchor, which induced less certainty about the direction of adjustment. The findings offer support to the integrative theory of anchoring. Additionally, the two studies revealed a "power struggle" between accuracy motivation and anchoring in influencing metacomprehension accuracy. Accuracy motivation could improve metacomprehension accuracy in spite of anchoring effect, but if anchoring effect is too strong, it could overpower the motivation effect. The implications of the findings were discussed.

Transthoracic CT-guided biopsy with multiplanar reconstruction image improves diagnostic accuracy of solitary pulmonary nodules

International Nuclear Information System (INIS)

Ohno, Yoshiharu; Hatabu, Hiroto; Takenaka, Daisuke; Imai, Masatake; Ohbayashi, Chiho; Sugimura, Kazuro

2004-01-01

Objective: To evaluate the utility of multiplanar reconstruction (MPR) image for CT-guided biopsy and determine factors of influencing diagnostic accuracy and the pneumothorax rate. Materials and methods: 390 patients with 396 pulmonary nodules underwent transthoracic CT-guided aspiration biopsy (TNAB) and transthoracic CT-guided cutting needle core biopsy (TCNB) as follows: 250 solitary pulmonary nodules (SPNs) underwent conventional CT-guided biopsy (conventional method), 81 underwent CT-fluoroscopic biopsy (CT-fluoroscopic method) and 65 underwent conventional CT-guided biopsy in combination with MPR image (MPR method). Success rate, overall diagnostic accuracy, pneumothorax rate and total procedure time were compared in each method. Factors affecting diagnostic accuracy and pneumothorax rate of CT-guided biopsy were statistically evaluated. Results: Success rates (TNAB: 100.0%, TCNB: 100.0%) and overall diagnostic accuracies (TNAB: 96.9%, TCNB: 97.0%) of MPR were significantly higher than those using the conventional method (TNAB: 87.6 and 82.4%, TCNB: 86.3 and 81.3%) (P<0.05). Diagnostic accuracy were influenced by biopsy method, lesion size, and needle path length (P<0.05). Pneumothorax rate was influenced by pathological diagnostic method, lesion size, number of punctures and FEV1.0% (P<0.05). Conclusion: The use of MPR for CT-guided lung biopsy is useful for improving diagnostic accuracy with no significant increase in pneumothorax rate or total procedure time

Does Direct Radiologist-Patient Verbal Communication Affect Follow-Up Compliance of Probably Benign Assessments?

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Bosma, Melissa S; Neal, Colleen H; Klein, Katherine A; Noroozian, Mitra; Patterson, Stephanie K; Helvie, Mark A

2016-03-01

The aim of this study was to determine whether direct verbal communication of results by a radiologist affected follow-up compliance rates for probably benign breast imaging findings. This study was institutional review board approved and HIPAA compliant. A retrospective search identified all patients from January 1, 2010 to December 31, 2010 who had breast findings newly assessed as probably benign (BI-RADS category 3). Patients were categorized by whether the radiologist or the technologist verbally communicated the result and follow-up recommendation. Patient adherence to 6-, 12-, and 24-month follow-up imaging recommendations was recorded. Compliance data were available for 770 of 819 patients in the study. Overall compliance was 83.0% (639 of 770) for 6-month examinations, 68.1% (524 of 770) for 6- and 12-month examinations, and 57.4% (442 of 770) for 6-, 12-, and 24-month examinations. For patients who initially underwent diagnostic mammography alone, there was no significant difference in compliance between those who had and those who did not have radiologist-patient communication (6 months, 81.9% vs 80.8% [P = .83]; 6 and 12 months, 70.8% vs 67.3% [P = .58]; 6, 12, and 24 months, 54.2% vs 58.4% [P = .53]). For patients who initially underwent diagnostic mammography alone versus ultrasound with or without diagnostic mammography, there was no significant difference in compliance (6 months, 81.1% vs 84.3% [P = .24]; 6 and 12 months, 68.1% vs 68.0% [P = .96]; 6, 12, and 24 months, 57.4% vs 57.4% [P = .00]). High initial compliance was achieved by radiologist or technologist verbal communication of findings and recommendations. Direct communication by the radiologist did not increase compliance compared with communication by a technologist. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Digital Breast Tomosynthesis Practice Patterns Following 2011 FDA Approval: A Survey of Breast Imaging Radiologists.

Science.gov (United States)

Gao, Yiming; Babb, James S; Toth, Hildegard K; Moy, Linda; Heller, Samantha L

2017-08-01

To evaluate uptake, patterns of use, and perception of digital breast tomosynthesis (DBT) among practicing breast radiologists. Institutional Review Board exemption was obtained for this Health Insurance Portability and Accountability Act-compliant electronic survey, sent to 7023 breast radiologists identified via the Radiological Society of North America database. Respondents were asked of their geographic location and practice type. DBT users reported length of use, selection criteria, interpretive sequences, recall rate, and reading time. Radiologist satisfaction with DBT as a diagnostic tool was assessed (1-5 scale). There were 1156 (16.5%) responders, 65.8% from the United States and 34.2% from abroad. Of these, 749 (68.6%) use DBT; 22.6% in academia, 56.5% private, and 21% other. Participants are equally likely to report use of DBT if they worked in academics versus in private practice (78.2% [169 of 216] vs 71% [423 of 596]) (odds ratio, 1.10; 95% confidence interval: 0.87-1.40; P = 1.000). Of nonusers, 43% (147 of 343) plan to adopt DBT. No US regional differences in uptake were observed (P = 1.000). Although 59.3% (416 of 702) of DBT users include synthetic 2D (s2D) for interpretation, only 24.2% (170 of 702) use s2D alone. Majority (66%; 441 of 672) do not perform DBT-guided procedures. Radiologist (76.6%) (544 of 710) satisfaction with DBT as a diagnostic tool is high (score ≥ 4/5). DBT is being adopted worldwide across all practice types, yet variations in examination indication, patient selection, utilization of s2D images, and access to DBT-guided procedures persist, highlighting the need for consensus and standardization. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Variations in management of mild prenatal hydronephrosis among maternal-fetal medicine obstetricians, and pediatric urologists and radiologists.

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Zanetta, Vitor C; Rosman, Brian M; Bromley, Bryan; Shipp, Thomas D; Chow, Jeanne S; Campbell, Jeffrey B; Herndon, C D Anthony; Passerotti, Carlo C; Cendron, Marc; Retik, Alan B; Nguyen, Hiep T

2012-11-01

There are no current guidelines for diagnosing and managing mild prenatal hydronephrosis. Variations in physician approach make it difficult to analyze outcomes and establish optimal management. We determined the variability of diagnostic approach and management regarding prenatal hydronephrosis among maternal-fetal medicine obstetricians, pediatric urologists and pediatric radiologists. Online surveys were sent to mailing lists for national societies for each specialty. Participants were surveyed regarding criteria for diagnosing mild prenatal hydronephrosis and recommendations for postnatal management, including use of antibiotic prophylaxis, followup scheduling and type of followup imaging. A total of 308 maternal-fetal medicine obstetricians, 126 pediatric urologists and 112 pediatric radiologists responded. Pediatric urologists and radiologists were divided between Society for Fetal Urology criteria and use of anteroposterior pelvic diameter for diagnosis, while maternal-fetal medicine obstetricians preferred using the latter. For postnatal evaluation radiologists preferred using personal criteria, while urologists preferred using anteroposterior pelvic diameter or Society for Fetal Urology grading system. There was wide variation in the use of antibiotic prophylaxis among pediatric urologists. Regarding the use of voiding cystourethrography/radionuclide cystography in patients with prenatal hydronephrosis, neither urologists nor radiologists were consistent in their recommendations. Finally, there was no agreement on length of followup for mild prenatal hydronephrosis. We observed a lack of uniformity regarding grading criteria in diagnosing hydronephrosis prenatally and postnatally among maternal-fetal medicine obstetricians, pediatric urologists and pediatric radiologists. There was also a lack of agreement on the management of mild intermittent prenatal hydronephrosis, resulting in these cases being managed inconsistently. A unified set of guidelines for

Radiologists' leading position in image-guided therapy.

Science.gov (United States)

Helmberger, Thomas; Martí-Bonmatí, Luis; Pereira, Philippe; Gillams, Alice; Martínez, Jose; Lammer, Johannes; Malagari, Katarina; Gangi, Afshin; de Baere, Thierry; Adam, E Jane; Rasch, Coen; Budach, Volker; Reekers, Jim A

2013-02-01

Image-guided diagnostic and therapeutic procedures are related to, or performed under, some kind of imaging. Such imaging may be direct inspection (as in open surgery) or indirect inspection as in endoscopy or laparoscopy. Common to all these techniques is the transformation of optical and visible information to a monitor or the eye of the operator. Image-guided therapy (IGT) differs by using processed imaging data acquired before, during and after a wide range of different imaging techniques. This means that the planning, performing and monitoring, as well as the control of the therapeutic procedure, are based and dependent on the "virtual reality" provided by imaging investigations. Since most of such imaging involves radiology in the broadest sense, there is a need to characterise IGT in more detail. In this paper, the technical, medico-legal and medico-political issues will be discussed. The focus will be put on state-of-the-art imaging, technical developments, methodological and legal requisites concerning radiation protection and licensing, speciality-specific limitations and crossing specialty borders, definition of technical and quality standards, and finally to the issue of awareness of IGT within the medical and public community. The specialty-specific knowledge should confer radiologists with a significant role in the overall responsibility for the imaging-related processes in various non-radiological specialties. These processes may encompass purchase, servicing, quality management, radiation protection and documentation, also taking responsibility for the definition and compliance with the legal requirements regarding all radiological imaging performed by non-radiologists.

Is Training Essential for Interpreting Cardiac Computed Tomography

International Nuclear Information System (INIS)

Ripsweden, J.; Brolin, E. Bacsovics; Brismar, T.; Nilsson, T.; Svensson, A.; Werner, C.; Cederlund, K.; Mir-Akbari, H.; Rueck, A.; Rasmussen, E.; Winter, R.

2009-01-01

Background: Cardiac computed tomography (CT) has gained increasing acceptance for diagnosing obstructive coronary artery disease (CAD). Several guidelines have been published on required education for proficiency in the interpretation of these examinations. Purpose: To describe the learning-curve effect of the interpretation of 100 consecutive cardiac CT examinations aimed at diagnosing CAD. The diagnostic accuracy of radiologists and radiographers was also compared. Material and Methods: Two radiologists and two radiographers, all with no prior experience in evaluation of cardiac CT, independently underwent a dedicated training program of 100 examinations randomized into 10 blocks (sessions), with 10 cases in each. They independently evaluated the coronary arteries regarding significant obstructive CAD. After every session, individual feedback on diagnostic accuracy and comparison with the corresponding invasive coronary angiography (currently regarded as the gold standard to detect coronary lesions) was given. The time required for interpretation was recorded. Results: The mean review time decreased (P<0.0001) successively during the 10 sessions for all the observers together. The first session had a mean review time of 32 min, and the last session 16 min. No significant improvement in sensitivity, specificity, or negative predictive value (NPV) was observed. For positive predictive value (PPV), there was an improvement for the radiologists (P<0.05), but not for the radiographers. The radiographers had a higher total specificity compared to the radiologists (P<0.01). Conclusion: The review time for novices in cardiac CT was approximately halved during the first 100 cases, with maintained accuracy. There was a learning-curve effect in PPV for the radiologists. The diagnostic accuracy of dedicated radiographers indicates that they might be considered to be included as part of the evaluation team

Software Aids for radiologists: Part 1, Useful Photoshop skills.

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Gross, Joel A; Thapa, Mahesh M

2012-12-01

The purpose of this review is to describe the use of several essential techniques and tools in Adobe Photoshop image-editing software. The techniques shown expand on those previously described in the radiologic literature. Radiologists, especially those with minimal experience with image-editing software, can quickly apply a few essential Photoshop tools to minimize the frustration that can result from attempting to navigate a complex user interface.

Analysis of prostate cancer localization toward improved diagnostic accuracy of transperineal prostate biopsy

Directory of Open Access Journals (Sweden)

Yoshiro Sakamoto

2014-09-01

Conclusions: The concordance of prostate cancer between prostatectomy specimens and biopsies is comparatively favorable. According to our study, the diagnostic accuracy of transperineal prostate biopsy can be improved in our institute by including the anterior portion of the Apex-Mid and Mid regions in the 12-core biopsy or 16-core biopsy, such that a 4-core biopsy of the anterior portion is included.

The corner of the gastroenterologist: What colonoscopy can do, what to ask to radiologist

International Nuclear Information System (INIS)

Bennato, Raffaele; Balzano, Antonio

2007-01-01

Colonoscopy is the diagnostic technique of choice for most colonic diseases and allows to explore the entire colonic mucosal surface and to visualize the mucosa of terminal ileum. When it is done with appropriate indications, significantly more clinically relevant diagnoses are made. Moreover, colonoscopy keeps an operative role in the treatment of some acute and chronic colonic diseases and it is the most effective colorectal cancer screening modality. The endoscopic exploration of colon is not infallible and presents rare complications. Programs of endoscopic training and practice, monitoring of quality indicators and continuous technological development are improving endoscopic diagnostic and therapeutic role. Appropriate indications for colonoscopy, its limits and complications and questions for the radiologist are discussed

Improving Accuracy and Simplifying Training in Fingerprinting-Based Indoor Location Algorithms at Room Level

Directory of Open Access Journals (Sweden)

Mario Muñoz-Organero

2016-01-01

Full Text Available Fingerprinting-based algorithms are popular in indoor location systems based on mobile devices. Comparing the RSSI (Received Signal Strength Indicator from different radio wave transmitters, such as Wi-Fi access points, with prerecorded fingerprints from located points (using different artificial intelligence algorithms, fingerprinting-based systems can locate unknown points with a few meters resolution. However, training the system with already located fingerprints tends to be an expensive task both in time and in resources, especially if large areas are to be considered. Moreover, the decision algorithms tend to be of high memory and CPU consuming in such cases and so does the required time for obtaining the estimated location for a new fingerprint. In this paper, we study, propose, and validate a way to select the locations for the training fingerprints which reduces the amount of required points while improving the accuracy of the algorithms when locating points at room level resolution. We present a comparison of different artificial intelligence decision algorithms and select those with better results. We do a comparison with other systems in the literature and draw conclusions about the improvements obtained in our proposal. Moreover, some techniques such as filtering nonstable access points for improving accuracy are introduced, studied, and validated.

Current opinion on clip placement after breast biopsy: A survey of practising radiologists in France and Quebec

International Nuclear Information System (INIS)

Thomassin-Naggara, I.; Jalaguier-Coudray, A.; Chopier, J.; Tardivon, A.; Trop, I.

2013-01-01

Aim: To investigate current practice regarding clip placement after breast biopsy. Materials and methods: In June 2011, an online survey instrument was designed using an Internet-based survey site ( (www.surveymonkey.com)) to assess practices and opinions of breast radiologists regarding clip placement after breast biopsy. Radiologists were asked to give personal practice data, describe their current practice regarding clip deployment under stereotactic, ultrasonographic, and magnetic resonance imaging (MRI) guidance, and describe what steps are taken to ensure quality control with regards to clip deployment. Results: The response rate was 29.9% in France (131 respondents) and 46.7% in Quebec (50 respondents). The great majority of respondents used breast markers in their practice (92.1% in France and 96% in Quebec). In both countries, most reported deploying a clip after percutaneous biopsy under stereotactic or MRI guidance. Regarding clip deployment under ultrasonography, 38% of Quebec radiologists systematically placed a marker after each biopsy, whereas 30% of French radiologists never placed a marker in this situation, mainly due to its cost. Finally, 56.4% of radiologists in France and 54% in Quebec considered that their practice regarding clip deployment after breast percutaneous biopsy had changed in the last 5 years. Conclusion: There continues to be variations in the use of biopsy clips after imaging-guided biopsies, particularly with regards to sonographic techniques. These variations are likely to decrease over time, with the standardization of relatively new investigation protocols

Clustering and training set selection methods for improving the accuracy of quantitative laser induced breakdown spectroscopy

International Nuclear Information System (INIS)

Anderson, Ryan B.; Bell, James F.; Wiens, Roger C.; Morris, Richard V.; Clegg, Samuel M.

2012-01-01

We investigated five clustering and training set selection methods to improve the accuracy of quantitative chemical analysis of geologic samples by laser induced breakdown spectroscopy (LIBS) using partial least squares (PLS) regression. The LIBS spectra were previously acquired for 195 rock slabs and 31 pressed powder geostandards under 7 Torr CO 2 at a stand-off distance of 7 m at 17 mJ per pulse to simulate the operational conditions of the ChemCam LIBS instrument on the Mars Science Laboratory Curiosity rover. The clustering and training set selection methods, which do not require prior knowledge of the chemical composition of the test-set samples, are based on grouping similar spectra and selecting appropriate training spectra for the partial least squares (PLS2) model. These methods were: (1) hierarchical clustering of the full set of training spectra and selection of a subset for use in training; (2) k-means clustering of all spectra and generation of PLS2 models based on the training samples within each cluster; (3) iterative use of PLS2 to predict sample composition and k-means clustering of the predicted compositions to subdivide the groups of spectra; (4) soft independent modeling of class analogy (SIMCA) classification of spectra, and generation of PLS2 models based on the training samples within each class; (5) use of Bayesian information criteria (BIC) to determine an optimal number of clusters and generation of PLS2 models based on the training samples within each cluster. The iterative method and the k-means method using 5 clusters showed the best performance, improving the absolute quadrature root mean squared error (RMSE) by ∼ 3 wt.%. The statistical significance of these improvements was ∼ 85%. Our results show that although clustering methods can modestly improve results, a large and diverse training set is the most reliable way to improve the accuracy of quantitative LIBS. In particular, additional sulfate standards and specifically

Gene masking - a technique to improve accuracy for cancer classification with high dimensionality in microarray data.

Science.gov (United States)

Saini, Harsh; Lal, Sunil Pranit; Naidu, Vimal Vikash; Pickering, Vincel Wince; Singh, Gurmeet; Tsunoda, Tatsuhiko; Sharma, Alok

2016-12-05

High dimensional feature space generally degrades classification in several applications. In this paper, we propose a strategy called gene masking, in which non-contributing dimensions are heuristically removed from the data to improve classification accuracy. Gene masking is implemented via a binary encoded genetic algorithm that can be integrated seamlessly with classifiers during the training phase of classification to perform feature selection. It can also be used to discriminate between features that contribute most to the classification, thereby, allowing researchers to isolate features that may have special significance. This technique was applied on publicly available datasets whereby it substantially reduced the number of features used for classification while maintaining high accuracies. The proposed technique can be extremely useful in feature selection as it heuristically removes non-contributing features to improve the performance of classifiers.

The impact of radiologists' expertise on screen results decisions in a CT lung cancer screening trial

International Nuclear Information System (INIS)

Heuvelmans, Marjolein A.; Vliegenthart, Rozemarijn; Oudkerk, Matthijs; Jong, Pim A. de; Mali, Willem P.; Groen, Harry J.M.

2015-01-01

To evaluate the impact of radiological expertise on screen result decisions in a CT lung cancer screening trial. In the NELSON lung cancer screening trial, the baseline CT result was based on the largest lung nodule's volume. The protocol allowed radiologists to manually adjust screen results in cases of high suspicion of benign or malignant nodule nature. Participants whose baseline CT result was based on a solid or part-solid nodule were included in this study. Adjustments by radiologists at baseline were evaluated. Histology was the reference for diagnosis or to confirm benignity and stability on subsequent CT examinations. A total of 3,318 participants (2,796 male, median age 58.0 years) were included. In 195 participants (5.9 %) the initial baseline screen result was adjusted by the radiologist. Adjustment was downwards from positive or indeterminate to negative in two and 119 participants, respectively, and from positive to indeterminate in 65 participants. None of these nodules turned out to be malignant. In 9/195 participants (4.6 %) the screen result was adjusted upwards from negative to indeterminate or indeterminate to positive; two nodules were malignant. In one in 20 cases of baseline lung cancer screening, nodules were reclassified by the radiologist, leading to a reduction of false-positive screen results. (orig.)

Improvement of early detection of breast cancer through collaborative multi-country efforts: Medical physics component.

Science.gov (United States)

Mora, Patricia; Faulkner, Keith; Mahmoud, Ahmed M; Gershan, Vesna; Kausik, Aruna; Zdesar, Urban; Brandan, María-Ester; Kurt, Serap; Davidović, Jasna; Salama, Dina H; Aribal, Erkin; Odio, Clara; Chaturvedi, Arvind K; Sabih, Zahida; Vujnović, Saša; Paez, Diana; Delis, Harry

2018-04-01

The International Atomic Energy Agency (IAEA) through a Coordinated Research Project on "Enhancing Capacity for Early Detection and Diagnosis of Breast Cancer through Imaging", brought together a group of mammography radiologists, medical physicists and radiographers; to investigate current practices and improve procedures for the early detection of breast cancer by strengthening both the clinical and medical physics components. This paper addresses the medical physics component. The countries that participated in the CRP were Bosnia and Herzegovina, Costa Rica, Egypt, India, Kenya, the Frmr. Yug. Rep. of Macedonia, Mexico, Nigeria, Pakistan, Philippines, Slovenia, Turkey, Uganda, United Kingdom and Zambia. Ten institutions participated using IAEA quality control protocols in 9 digital and 3 analogue mammography equipment. A spreadsheet for data collection was generated and distributed. Evaluation of image quality was done using TOR MAX and DMAM2 Gold phantoms. QC results for analogue equipment showed satisfactory results. QC tests performed on digital systems showed that improvements needed to be implemented, especially in thickness accuracy, signal difference to noise ratio (SDNR) values for achievable levels, uniformity and modulation transfer function (MTF). Mean glandular dose (MGD) was below international recommended levels for patient radiation protection. Evaluation of image quality by phantoms also indicated the need for improvement. Common activities facilitated improvement in mammography practice, including training of medical physicists in QC programs and infrastructure was improved and strengthened; networking among medical physicists and radiologists took place and was maintained over time. IAEA QC protocols provided a uniformed approach to QC measurements. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Direct Interactive Public Education by Breast Radiologists About Screening Mammography: Impact on Anxiety and Empowerment.

Science.gov (United States)

Lee, Jiyon; Hardesty, Lara A; Kunzler, Nathan M; Rosenkrantz, Andrew B

2016-01-01

Anxiety has been called a "harm" of screening mammography. The authors provided direct, interactive education to lay audiences and measured these sessions' impact on anxiety and any increased understanding of breast cancer screening. Academic breast radiologist provided seven 1-hour sessions of structured lectures and question-and-answer periods. Lay language and radiologic images were used to discuss disease background, screening guidelines, and areas of debate. One hundred seventeen participants (mean age, 45 ± 15 years) completed voluntary, anonymous, institutional review board-approved pre and postsession questionnaires relaying their attitudes regarding screening and the impact of the sessions. Results are summarized descriptively. Mean reported anxiety regarding screening (on a scale ranging from 1-5; 1 = no anxiety) was 2.5 ± 1.3. Anxiety was attributed to unknown results (56.4%), anticipation of pain (21.8%), known risk factors (14.5%), general uncertainty (12.7%), waiting for results (9.1%), possibility of more procedures (3.6%), and personal breast cancer history (3.6%). Ninety-seven percent reported that immediate results would lower anxiety (78% of those women indicated a 75%-100% decrease in anxiety); 93% reported that radiologist consultation with images would lower anxiety (75.6% indicated a 75%-100% decrease in anxiety). After the lecture, women reported (on a scale ranging from 1-5) increased understanding of the topic (4.7 ± 0.6), encouragement to screen (4.6 ± 0.7), and reduced anxiety (4.0 ± 1.1). Ninety-seven percent to 100% provided correct responses to these questions: rationale for screening in the absence of family history, recall does not equate to cancer diagnosis, benefit of prior films, and continued importance of physical examination. Attendees of radiologist-provided direct public lectures reported decreased anxiety and improved knowledge regarding screening mammography. The resultant reduced anxiety ("harm") and educational

An efficient optimization method to improve the measuring accuracy of oxygen saturation by using triangular wave optical signal

Science.gov (United States)

Li, Gang; Yu, Yue; Zhang, Cui; Lin, Ling

2017-09-01

The oxygen saturation is one of the important parameters to evaluate human health. This paper presents an efficient optimization method that can improve the accuracy of oxygen saturation measurement, which employs an optical frequency division triangular wave signal as the excitation signal to obtain dynamic spectrum and calculate oxygen saturation. In comparison to the traditional method measured RMSE (root mean square error) of SpO2 which is 0.1705, this proposed method significantly reduced the measured RMSE which is 0.0965. It is notable that the accuracy of oxygen saturation measurement has been improved significantly. The method can simplify the circuit and bring down the demand of elements. Furthermore, it has a great reference value on improving the signal to noise ratio of other physiological signals.

Health issues and the practicing radiologist: defining concepts and developing recommendations for leave options and policies.

Science.gov (United States)

Heilbrun, Marta E; Bender, Claire E; Truong, Hang B; Bluth, Edward I

2013-09-01

Radiologists today are faced with the challenges of maintaining and balancing individual and family health needs and the demands of the workplace. To provide the highest quality and safest care of our patients, a corresponding ethos of support for a healthy workforce is required. There is a paucity of targeted information describing protections for and maintenance of the health of the practicing radiologist, in both private and academic settings. However, a review of existing family and medical leave policies may be helpful to practice leaders and practicing radiologists as a platform for the development of strategic workforce plans. This writing, by members of the ACR Commission on Human Resources, addresses the following areas: (1) medical leave, (2) maternity and/or paternity leave, and (3) disability. Copyright © 2013 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Improving diagnostic accuracy using agent-based distributed data mining system.

Science.gov (United States)

Sridhar, S

2013-09-01

The use of data mining techniques to improve the diagnostic system accuracy is investigated in this paper. The data mining algorithms aim to discover patterns and extract useful knowledge from facts recorded in databases. Generally, the expert systems are constructed for automating diagnostic procedures. The learning component uses the data mining algorithms to extract the expert system rules from the database automatically. Learning algorithms can assist the clinicians in extracting knowledge automatically. As the number and variety of data sources is dramatically increasing, another way to acquire knowledge from databases is to apply various data mining algorithms that extract knowledge from data. As data sets are inherently distributed, the distributed system uses agents to transport the trained classifiers and uses meta learning to combine the knowledge. Commonsense reasoning is also used in association with distributed data mining to obtain better results. Combining human expert knowledge and data mining knowledge improves the performance of the diagnostic system. This work suggests a framework of combining the human knowledge and knowledge gained by better data mining algorithms on a renal and gallstone data set.

Is the application of CAD useful for radiologists for passing the official tests required for outpatient breast imaging?

International Nuclear Information System (INIS)

Malich, A.; Beier, A.; Gorna, R.; Bank, P.

2007-01-01

Purpose: to analyze whether currently available CAD systems meet the diagnostic requirements for passing screening tests (first reader CAD) and to analyze whether the additional usage of CAD systems provides significant support for the diagnosing radiologist on the basis of official screening test cases (second reading by CAD). Material and methods: 200 images of 100 mammographies of 50 patients of an official screening test case collection were analyzed double-blind with and without CAD printouts (iCAD, U.S.A.) by three radiologists: one experienced in breast analysis and CAD application, one experienced in mammography analysis but inexperienced in CAD usage, one with minimal experience with breast analysis and CAD application. All radiologists measured the largest diameter of any malignant mass. The mean value of these calculations was correlated to the largest diameter given by CAD prompts. Results: the mean sensitivity and specificity increased slightly as a result of the additional usage of CAD (1 and 0.6%, resp.). Both values are not statistically significant. The highest effect was measured for the radiologist with CAD experience, while no effect was measured for the inexperienced radiologist. CAD met the sensitivity requirements but not the specificity criteria (96 and 20.3%, resp.). The sizes given by CAD prompts corresponded significantly with the real sizes (r = 0.45, p < 0.05). (orig.)

Shielding effect of lead glasses on radiologists' eye lens exposure in interventional procedures

International Nuclear Information System (INIS)

Hu, Panpan; Kong, Yan; Chen, Bo; Liu, Qianqian; Zhuo, Weihai; Liu, Haikuan

2017-01-01

To study the shielding effect of radiologists' eye lens with lead glasses of different equivalent thicknesses and sizes in interventional radiology procedures. Using the human voxel phantom with a more accurate model of the eye and MCNPX software, eye lens doses of the radiologists who wearing different kinds of lead glasses were simulated, different beam projections were taken into consideration during the simulation. Measurements were also performed with the physical model to verify simulation results. Simulation results showed that the eye lens doses were reduced by a factor from 3 to 9 when wearing a 20 cm"2-sized lead glasses with the equivalent thickness ranging from 0.1 to 1.0 mm Pb. The increase of dose reduction factor (DRF) was not significant whenever increase the lead equivalent of glasses of which larger than 0.35 mm. Furthermore, the DRF was proportional to the size of glass lens from 6 to 30 cm"2 with the same lead equivalent. The simulation results were in well agreements with the measured ones. For more reasonable and effective protection of the eye lens of interventional radiologists, a pair of glasses with a lead equivalent of 0.5 mm Pb and large-sized (at least 27 cm"2 per glass) lens are recommended (authors)

The contribution of educational class in improving accuracy of cardiovascular risk prediction across European regions

DEFF Research Database (Denmark)

Ferrario, Marco M; Veronesi, Giovanni; Chambless, Lloyd E

2014-01-01

OBJECTIVE: To assess whether educational class, an index of socioeconomic position, improves the accuracy of the SCORE cardiovascular disease (CVD) risk prediction equation. METHODS: In a pooled analysis of 68 455 40-64-year-old men and women, free from coronary heart disease at baseline, from 47...

Added value of prone CT in the assessment of honeycombing and classification of usual interstitial pneumonia pattern.

Science.gov (United States)

Kim, Minjae; Lee, Sang Min; Song, Jae-Woo; Do, Kyung-Hyun; Lee, Hyun Joo; Lim, Soyeoun; Choe, Jooae; Park, Kye Jin; Park, Hyo Jung; Kim, Hwa Jung; Seo, Joon Beom

2017-06-01

To retrospectively investigate whether prone CT improves identification of honeycombing and classification of UIP patterns in terms of interobserver agreement and accuracy using pathological results as a reference standard. Institutional review board approval with waiver of patients' informed consent requirement was obtained. HRCTs of 86 patients with pathologically proven UIP, NSIP and chronic HP between January 2011 and April 2015 were evaluated by 8 observers. Observers were asked to review supine only set and supine and prone combined set and determine the presence of honeycombing and UIP classification (UIP, possible UIP, inconsistent with UIP). The diagnosis was regarded as correct when UIP pattern on CT corresponded to pathological UIP. Interobserver agreement of honeycombing identification among radiologists was only fair on the supine and combined set (weighted κ=0.31 and 0.34). Additional review of prone images demonstrated a significant improvement in interobserver agreement (weighted κ) of UIP classification from 0.25 to 0.33. Prone CT conferred a significant improvement in interobserver agreement of UIP classification for trainee radiologists (from 0.10 to 0.34) while no improvement was found for board-certified radiologists (from 0.35 to 0.31). There were no significant differences in the accuracy of UIP pattern with reference to pathological results between the supine and combined set (78.8% (145/184) and 81.3% (179/220), P=0.612). Additional review of prone CT can improve overall interobserver agreement of UIP classification among radiologists with variable experiences, particularly for less experienced radiologists, while no improvement was found in honeycombing identification. Copyright © 2017 Elsevier B.V. All rights reserved.

Inter-radiologist agreement for CT scoring of pediatric splenic injuries and effect on an established clinical practice guideline.

Science.gov (United States)

Leschied, Jessica R; Mazza, Michael B; Davenport, Matthew; Chong, Suzanne T; Smith, Ethan A; Hoff, Carrie N; Ladino-Torres, Maria F; Khalatbari, Shokoufeh; Ehrlich, Peter F; Dillman, Jonathan R

2016-02-01

The American Pediatric Surgical Association (APSA) advocates for the use of a clinical practice guideline to direct management of hemodynamically stable pediatric spleen injuries. The clinical practice guideline is based on the CT score of the spleen injury according to the American Association for the Surgery of Trauma (AAST) CT scoring system. To determine the potential effect of radiologist agreement for CT scoring of pediatric spleen injuries on an established APSA clinical practice guideline. We retrospectively analyzed blunt splenic injuries occurring in children from January 2007 to January 2012 at a single level 1 trauma center (n = 90). Abdominal CT exams performed at clinical presentation were reviewed by four radiologists who documented the following: (1) splenic injury grade (AAST system), (2) arterial extravasation and (3) pseudoaneurysm. Inter-rater agreement for AAST injury grade was assessed using the multi-rater Fleiss kappa and Kendall coefficient of concordance. Inter-rater agreement was assessed using weighted (AAST injury grade) or prevalence-adjusted bias-adjusted (binary measures) kappa statistics; 95% confidence intervals were calculated. We evaluated the hypothetical effect of radiologist disagreement on an established APSA clinical practice guideline. Inter-rater agreement was good for absolute AAST injury grade (kappa: 0.64 [0.59–0.69]) and excellent for relative AAST injury grade (Kendall w: 0.90). All radiologists agreed on the AAST grade in 52% of cases. Based on an established clinical practice guideline, radiologist disagreement could have changed the decision for intensive care management in 11% (10/90) of children, changed the length of hospital stay in 44% (40/90), and changed the time to return to normal activity in 44% (40/90). Radiologist agreement when assigning splenic AAST injury grades is less than perfect, and disagreements have the potential to change management in a substantial number of pediatric patients.

Inter-radiologist agreement for CT scoring of pediatric splenic injuries and effect on an established clinical practice guideline

International Nuclear Information System (INIS)

Leschied, Jessica R.; Smith, Ethan A.; Ladino-Torres, Maria F.; Dillman, Jonathan R.; Mazza, Michael B.; Chong, Suzanne T.; Hoff, Carrie N.; Davenport, Matthew S.; Khalatbari, Shokoufeh; Ehrlich, Peter F.

2016-01-01

The American Pediatric Surgical Association (APSA) advocates for the use of a clinical practice guideline to direct management of hemodynamically stable pediatric spleen injuries. The clinical practice guideline is based on the CT score of the spleen injury according to the American Association for the Surgery of Trauma (AAST) CT scoring system. To determine the potential effect of radiologist agreement for CT scoring of pediatric spleen injuries on an established APSA clinical practice guideline. We retrospectively analyzed blunt splenic injuries occurring in children from January 2007 to January 2012 at a single level 1 trauma center (n = 90). Abdominal CT exams performed at clinical presentation were reviewed by four radiologists who documented the following: (1) splenic injury grade (AAST system), (2) arterial extravasation and (3) pseudoaneurysm. Inter-rater agreement for AAST injury grade was assessed using the multi-rater Fleiss kappa and Kendall coefficient of concordance. Inter-rater agreement was assessed using weighted (AAST injury grade) or prevalence-adjusted bias-adjusted (binary measures) kappa statistics; 95% confidence intervals were calculated. We evaluated the hypothetical effect of radiologist disagreement on an established APSA clinical practice guideline. Inter-rater agreement was good for absolute AAST injury grade (kappa: 0.64 [0.59-0.69]) and excellent for relative AAST injury grade (Kendall w: 0.90). All radiologists agreed on the AAST grade in 52% of cases. Based on an established clinical practice guideline, radiologist disagreement could have changed the decision for intensive care management in 11% (10/90) of children, changed the length of hospital stay in 44% (40/90), and changed the time to return to normal activity in 44% (40/90). Radiologist agreement when assigning splenic AAST injury grades is less than perfect, and disagreements have the potential to change management in a substantial number of pediatric patients. (orig.)

Inter-radiologist agreement for CT scoring of pediatric splenic injuries and effect on an established clinical practice guideline

Energy Technology Data Exchange (ETDEWEB)

Leschied, Jessica R.; Smith, Ethan A.; Ladino-Torres, Maria F.; Dillman, Jonathan R. [University of Michigan Health System, Department of Radiology, Section of Pediatric Radiology, C.S. Mott Children' s Hospital, Ann Arbor, MI (United States); Mazza, Michael B.; Chong, Suzanne T.; Hoff, Carrie N. [University of Michigan Health System, Department of Radiology, Division of Emergency Radiology, C.S. Mott Children' s Hospital, Ann Arbor, MI (United States); Davenport, Matthew S. [University of Michigan Health System, Department of Radiology, Division of Abdominal Imaging, C.S. Mott Children' s Hospital, Ann Arbor, MI (United States); Khalatbari, Shokoufeh [University of Michigan, Michigan Institute for Clinical and Health Research, Ann Arbor, MI (United States); Ehrlich, Peter F. [University of Michigan Health System, Department of Surgery, Section of Pediatric Surgery, C.S. Mott Children' s Hospital, Ann Arbor, MI (United States)

2016-02-15

The American Pediatric Surgical Association (APSA) advocates for the use of a clinical practice guideline to direct management of hemodynamically stable pediatric spleen injuries. The clinical practice guideline is based on the CT score of the spleen injury according to the American Association for the Surgery of Trauma (AAST) CT scoring system. To determine the potential effect of radiologist agreement for CT scoring of pediatric spleen injuries on an established APSA clinical practice guideline. We retrospectively analyzed blunt splenic injuries occurring in children from January 2007 to January 2012 at a single level 1 trauma center (n = 90). Abdominal CT exams performed at clinical presentation were reviewed by four radiologists who documented the following: (1) splenic injury grade (AAST system), (2) arterial extravasation and (3) pseudoaneurysm. Inter-rater agreement for AAST injury grade was assessed using the multi-rater Fleiss kappa and Kendall coefficient of concordance. Inter-rater agreement was assessed using weighted (AAST injury grade) or prevalence-adjusted bias-adjusted (binary measures) kappa statistics; 95% confidence intervals were calculated. We evaluated the hypothetical effect of radiologist disagreement on an established APSA clinical practice guideline. Inter-rater agreement was good for absolute AAST injury grade (kappa: 0.64 [0.59-0.69]) and excellent for relative AAST injury grade (Kendall w: 0.90). All radiologists agreed on the AAST grade in 52% of cases. Based on an established clinical practice guideline, radiologist disagreement could have changed the decision for intensive care management in 11% (10/90) of children, changed the length of hospital stay in 44% (40/90), and changed the time to return to normal activity in 44% (40/90). Radiologist agreement when assigning splenic AAST injury grades is less than perfect, and disagreements have the potential to change management in a substantial number of pediatric patients. (orig.)

Effectiveness of blood pressure educational and evaluation program for the improvement of measurement accuracy among nurses.

Science.gov (United States)

Rabbia, Franco; Testa, Elisa; Rabbia, Silvia; Praticò, Santina; Colasanto, Claudia; Montersino, Federica; Berra, Elena; Covella, Michele; Fulcheri, Chiara; Di Monaco, Silvia; Buffolo, Fabrizio; Totaro, Silvia; Veglio, Franco

2013-06-01

To assess the procedure for measuring blood pressure (BP) among hospital nurses and to assess if a training program would improve technique and accuracy. 160 nurses from Molinette Hospital were included in the study. The program was based upon theoretical and practical lessons. It was one day long and it was held by trained nurses and physicians who have practice in the Hypertension Unit. An evaluation of nurses' measuring technique and accuracy was performed before and after the program, by using a 9-item checklist. Moreover we calculated the differences between measured and effective BP values before and after the training program. At baseline evaluation, we observed inadequate performance on some points of clinical BP measurement technique, specifically: only 10% of nurses inspected the arm diameter before placing the cuff, 4% measured BP in both arms, 80% placed the head of the stethoscope under the cuff, 43% did not remove all clothing that covered the location of cuff placement, did not have the patient seat comfortably with his legs uncrossed and with his back and arms supported. After the training we found a significant improvement in the technique for all items. We didn't observe any significant difference of measurement knowledge between nurses working in different settings such as medical or surgical departments. Periodical education in BP measurement may be required, and this may significantly improve the technique and consequently the accuracy.

Quality of referral: What information should be included in a request for diagnostic imaging when a patient is referred to a clinical radiologist?

Science.gov (United States)

G Pitman, Alexander

2017-06-01

Referral to a clinical radiologist is the prime means of communication between the referrer and the radiologist. Current Australian and New Zealand government regulations do not prescribe what clinical information should be included in a referral. This work presents a qualitative compilation of clinical radiologist opinion, relevant professional recommendations, governmental regulatory positions and prior work on diagnostic error to synthesise recommendations on what clinical information should be included in a referral. Recommended requirements on what clinical information should be included in a referral to a clinical radiologist are as follows: an unambiguous referral; identity of the patient; identity of the referrer; and sufficient clinical detail to justify performance of the diagnostic imaging examination and to confirm appropriate choice of the examination and modality. Recommended guideline on the content of clinical detail clarifies when the information provided in a referral meets these requirements. High-quality information provided in a referral allows the clinical radiologist to ensure that exposure of patients to medical radiation is justified. It also minimises the incidence of perceptual and interpretational diagnostic error. Recommended requirements and guideline on the clinical detail to be provided in a referral to a clinical radiologist have been formulated for professional debate and adoption. © 2017 The Royal Australian and New Zealand College of Radiologists.