Mark D. Kovacs

Image toggling saves time in mammography

Abstract. When two images are perfectly aligned, even subtle differences are readily detected when the images are “toggled” back and forth in the same location. However, substantial changes between two photographs can be missed if the images are misaligned (“change blindness”). Nevertheless, recent work from our lab, testing nonradiologists, suggests that toggling misaligned photographs leads to superior performance compared to side-by-side viewing (SBS). In order to determine if a benefit of toggling misaligned images may be observed in clinical mammography, we developed an image toggling technique where pairs of new and prior breast imaging exam images could be efficiently toggled back and forth. Twenty-three radiologists read 10 mammograms evenly divided in toggle and SBS modes. The toggle mode led to a 6-s benefit in reaching a decision [t(22)=5.11, p<.05]. The toggle viewing mode also led to a 5% improvement in diagnostic accuracy, though in our small sample this effect was not statistically reliable. Time savings were found even though successive mammograms were not perfectly aligned. Given the ever-increasing caseload for radiologists, this simple manipulation of how the images are viewed could save valuable time in clinical practice, allowing radiologists to read more cases or spend more time on difficult cases.

Evaluation of Lossy Data Compression in Primary Interpretation for Full-Field Digital Mammography

OBJECTIVE. For full-field digital mammography (FFDM), federal regulations prohibit lossy data compression for primary reading and archiving, unlike all other medical images, where reading physicians can apply their professional judgment in implementing lossy compression. Faster image transfer, lower costs, and greater access to expert mammographers would result from development of a safe standard for primary interpretation and archive of lossy-compressed FFDM images. This investigation explores whether JPEG 2000 80:1 lossy data compression affects clinical accuracy in digital mammography. MATERIALS AND METHODS. Randomized FFDM cases (n = 194) were interpreted by six experienced mammographers with and without JPEG 2000 80:1 lossy compression applied. A cancer-enriched population was used, with just less than half of the cases (42%) containing subtle (< 1 cm) biopsy-proven cancerous lesions, and the remaining cases were negative as proven by 2-year follow-up. Data were analyzed using the jackknife alternative free-response ROC (JAFROC) method. RESULTS. The differences in reader performance between lossy-compressed and non-lossy-compressed images using lesion localization (0.660 vs 0.671), true-positive fraction (0.879 vs 0.879), and false-positive fraction (0.283 vs 0.271) were not statistically significant. There was no difference in the JAFROC figure of merit between lossy-compressed and non-lossy-compressed images, with a mean difference of -0.01 (95% CI, -0.03 to 0.01; F1,5 = 2.30; p = 0.189). CONCLUSION. These results suggest that primary interpretation of JPEG 2000 80:1 lossy-compressed FFDM images may be viable without degradation of clinical quality. Benefits would include lower storage costs, faster telemammography, and enhanced access to expert mammographers.

Differentiating biliary cystadenomas from benign hepatic cysts: Preliminary analysis of new predictive imaging features

OBJECTIVE To identify performance of imaging features in differentiating hepatic cysts from biliary cystadenomas of the liver. METHODS 25 pathologically confirmed hepatic cystic lesions (hepatic cysts or biliary cystadenomas) were evaluated retrospectively and predetermined imaging features assessed for performance in differentiation. RESULTS Any septation which arose from a cyst wall without external indentation had a very high association with biliary cystadenoma, while the presence of a thick septation had only a moderate association. CONCLUSIONS The relationship between septations and the wall of the cystic lesion performed better than previously reported features including thick septations.

Reply to "The Use of Lossy Compression of Digital Mammograms for Primary Interpretation and Image Retention".

AJR 2015; 205:W642 0361–803X/15/2056–W642

App Review: Management Guide for Incidental Findings on CT and MRI

While the user should read and understand the relevant ACR white papers thoroughly, so that subtleties are not lost, the app is an efficient, easy to use, and free resource for managing a wide variety of incidental findings encountered on CT or MRI.

App Review: The Radiology Assistant 2.0

App Specs App Icon URL https://is2-ssl.mzstatic.com/image/thumb/ Purple128/v4/b5/53/ab/b553abf2-be0c-a5d1-493ead937128ce1c/AppIcon-1x_U007emarketing-0-0-GLES2_ U002c0-512MB-sRGB-0-0-0-85-220-0-0-0-8.png/246x0w.jpg App Name: The Radiology Assistant 2.0 (Version 1.1.0) App Developer: BestApps BV App Developer Website: https://itunes.apple.com/us/ developer/bestapps-bv/id329677410 App Price: Free to Download; In-app-purchase of

Cesarean-Section Scar Endometrioma: A Case Report and Review of the Literature

5.99 for a 1-year subscription Apple App Store URL: https://itunes.apple.com/us/app/ radiology-assistant-2-0/id1173853906?mt=8 Google Play Store URL: https://play.google.com/store/ apps/details?id=nl.radiologyassistant.android&hl=en (The Radiology Assistant Version 1.1.1) Category: Medical Tags: radiology reference, free, iPhone-compatible Works Offline: Y FDA Approval: N/A Promotion Code: N/A Quick Review (1 star: lowest/5 stars: highest) Overall Rating (1–5): 4.5 Content (1–5): 4 Usability (1–5): 5 Pros: Covers many common pathologies as well as normal anatomy across radiology subspecialties, well-labeled images from multiple imaging modalities, inexpensive, user-friendly interface. Cons: Only iPhone and iPad compatible (previous version of app is android compatible). Content is not automatically updated and virtually no nuclear medicine specific content. At a Glance: User-friendly mobile device application, optimized for medical students and residents, that provides a searchable, offline database of up-to-date radiological articles which showcase many images and descriptions of common radiological pathologies as well as normal radiographic anatomy.

Impact of low-kVp scan technique on oral contrast density at abdominopelvic CT

Endometriomas can occur after any surgery where there is endometrial manipulation, and there are a number of reports of endometriomas developing in the abdominal wall at the site of the Pfannenstiel incision following Cesarean-section. Although this is ultimately a histopathologically-confirmed diagnosis, preoperative imaging including ultrasound, computed tomography, and magnetic resonance imaging may be helpful in the diagnosis and assessment. We report a pathology-confirmed case of Cesarean-section endometrioma with a classic, clinical presentation and imaging findings on computed tomography. A comprehensive literature review and discussion of the multi-modality imaging appearance of Cesarean-section endometrioma is also provided.