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Rationale and Objectives In diagnostic accuracy studies, cases in which a reader does not see the condition of interest are often given the same score for ROC analysis (e.g. confidence score of 0%). However, many of these cases can be further distinguished and doing so may result in more robust ROC results. Materials and Methods We examined two recent, real-world studies which used different procedures to encourage readers to further distinguish subjects who appear to be without the condition of interest. For each study, we calculated the results under two conditions. In the “zeros distinguished” (ZD) condition, we incorporated the confidence scores collected to further distinguish the normal-looking subjects. In the “zeros not distinguished” (ZND) condition, we disregarded these scores and simply gave the unit of analysis a score of zero whenever the reader did not identify the condition of interest in that unit. We compared the two conditions on (1) coverage of the ROC space and (2) discrepancy between parametric and nonparametric results. Results Compared to the ZND condition, coverage of the ROC space was improved in the ZD condition for all ROC curves in both studies. In the first study, there was a significant reduction in the discrepancy between parametric and nonparametric results (median discrepancy in ZND vs ZD condition: 0.033 vs 0.011, p = 0.012). A similar reduction was not seen in the second study, though the discrepancies were very low in both conditions (0.003 vs 0.006, p = 0.313). Conclusion Prompting readers to further distinguish cases in which they do not see the condition of interest may result in more robust ROC results, though further exploration of this topic is warranted.

Previous studies have reported mixed results regarding whether the use of structured reporting (SR) leads to a change in interpretation times. The objective of this study was to quantify any change in interpretation times after the implementation of SR for multiple sclerosis (MS) follow-up magnetic resonance imaging (MRI) of the brain.Interpretation times before and after the transition to MS MRI SR were compared over a 5-year period. To control for changing practice patterns, a control group of non-MS (intracranial masses) reports not using SR was also assessed. In a secondary analysis, interpretation times for 2D and 3D MRI MS protocols after the initiation of SR were compared to determine whether increased image number with the 3D protocol affected interpretation times.Mean and median interpretation times before the initiation of SR for MS MRI were 11.0 and 8.0 minutes versus 8.5 and 6.0 minutes after the implementation of SR (p0.001). Although non-MS MRI interpretation times also decreased, an interaction analysis demonstrated that the decrease in MS interpretation times was significantly higher (p0.001). Mean and median interpretation times using 3D protocols were slighter increased compared to interpretation times with 2D protocols (p = 0.036).After the implementation of SR for MS follow-up MRI at our institution, interpretation times significantly decreased despite the increased number of images with some of the examinations due to the adoption of 3D protocols. The adoption of SR for MS MRI follow-up scans may improve radiologist efficiency.

To evaluate the effect of enema and dietary restrictions on prostate MR image quality metrics and to assess inter-reader agreement for these metrics.This retrospective study included 195 men divided into groups based on their compliance with preparation instructions before prostate MRI (Enema + Diet, n = 98; Enema, n = 42; Diet, n = 35; Control [no compliance], n = 20). Four readers independently assessed six image quality metrics on a 5-point scale. Between-group comparisons were made using Wilcoxon rank sum test. Inter-reader agreement was calculated using Fleiss' kappa.Compared with the Control group, image quality with respect to rectal stool/gas, distortion of diffusion-weighted images, overall image quality, and confidence in assessment was higher in the Enema + Diet, Enema, and Diet groups (p 0.05 for all comparisons). The Enema + Diet and Enema groups had significantly higher scores than the Diet group for rectal stool/gas (p0.001 and 0.005, respectively). The Enema + Diet and Diet groups had higher scores than the Control group for rectal peristalsis (p = 0.027 and 0.009, respectively), but there were no significant differences in motion artifacts on T2-weighted images. Agreement among readers was fair, with kappa values ranging from 0.25 to 0.37.Enema and dietary restriction can improve the quality of prostate MRI by decreasing rectal distension and distortion of diffusion-weighted images and by increasing reader confidence in image assessment. Inter-reader agreement using subjective criteria for analysis of MRI quality is fair.

Rational and Objectives This study aims to evaluate the diagnostic utility of breast imaging using transmission ultrasound. We present readers' accuracy in determining whether a breast lesion is a cyst versus a solid using transmission ultrasound as an adjunct to mammography. Materials and Methods This retrospective multi-reader, multi-case receiver operating characteristic study included 37 lesions seen on mammography and transmission ultrasound. Cyst cases were confirmed as cysts using their appearance on handheld ultrasound. Solid cases were confirmed as solids with pathology results. Fourteen readers performed blinded, randomized reads with mammography + quantitative transmission scan images, assigning both a confidence score (0–100) and a binary classification of cyst or solid. A 95% percentile bootstrap confidence interval (CI) was computed for the readers' mean receiver operating characteristic area, sensitivity, and specificity. Results Using the readers' binary classification of cyst or solid lesions, the mean sensitivity and specificity were 0.933 [95% CI: 0.837, 0.995] and 0.858 [95% CI: 0.701, 0.985], respectively. When the readers' confidence scores were used to distinguish a cyst versus solid, the mean receiver operating characteristic area was 0.920 [95% CI: 0.827, 0.985]. Conclusions Transmission ultrasound can provide an accurate assessment of a cyst versus a solid lesion in the breast. Prospective clinical trials will further delineate the role of transmission ultrasound as an adjunct to mammography to increase specificity in breast evaluation.