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Background: Compared to 1.5 T, 3 T magnetic resonance imaging (MRI) increases signal-to-noise ratio leading to improved image quality. However, its clinical relevance in clinically isolated syndrome suggestive of multiple sclerosis remains uncertain. Objectives: The purpose of this study was to investigate how 3 T MRI affects the agreement between raters on lesion detection and diagnosis. Methods: We selected 30 patients and 10 healthy controls from our ongoing prospective multicentre cohort. All subjects received baseline 1.5 and 3 T brain and spinal cord MRI. Patients also received follow-up brain MRI at 3–6 months. Four experienced neuroradiologists and four less-experienced raters scored the number of lesions per anatomical region and determined dissemination in space and time (McDonald 2010). Results: In controls, the mean number of lesions per rater was 0.16 at 1.5 T and 0.38 at 3 T (p = 0.005). For patients, this was 4.18 and 4.40, respectively (p = 0.657). Inter-rater agreement on involvement per anatomical region and dissemination in space and time was moderate to good for both field strengths. 3 T slightly improved agreement between experienced raters, but slightly decreased agreement between less-experienced raters. Conclusion: Overall, the interobserver agreement was moderate to good. 3 T appears to improve the reading for experienced readers, underlining the benefit of additional training. [ABSTRACT FROM AUTHOR]

Intraoperative assessment of pancreatic parenchymal margin during pancreatectomies is challenging and misinterpretation by the pathologist is a cause of incorrect frozen section (FS) diagnosis. Although the current literature supports that pancreatic margin FS diagnosis and its accuracy has no impact on the patient outcome for pancreatic ductal adenocarcinoma (PDAC) patients and reexcision in an attempt to achieve a negative intraoperative pancreatic margin after positive FS is not associated with increased overall survival; still it remains a routine practice in many institutions. To this end, we sought to assess the interobserver variation and accuracy of FS diagnosis between subspecialized gastrointestinal/pancreatobiliary (GI) and general pathologists. Seventy seven consecutive pancreatic parenchymal margin FSs performed on pancreatectomies for PDAC from 2010 to 2013 were retrieved at our institution. These were retrospectively evaluated by 2 GI and 2 general pathologists independently without knowledge of the original FS diagnosis or the final diagnosis. The specificity, sensitivity, positive predictive value, negative predictive value, and accuracy of GI versus general pathologist was 97.8% versus 87.5%, 61.1% versus 66.7%, 78.6% versus 41.4%, 95% versus 95.2%, and 93.5% versus 85.1%, respectively. The interobserver agreement between GI and general pathologists was fair (κ = .337, P < .001). The interobserver agreement between 2 GI pathologists was fair (κ = .373, P = .0005) and between 2 general pathologists was slight (κ = .195, P = .042). Although overall accuracy of subspecialized GI pathologists was higher than that of general pathologists, none had an accuracy of 100%. Our study reaffirms the challenging nature of these FSs. [ABSTRACT FROM AUTHOR]

The ankle-brachial index (ABI) post exercise is claimed to play a complementary role in the diagnosis or exclusion of intermittent claudication (IC). The interobserver variability of ABI measurements at rest and post exercise in patients with typical symptoms of IC is the subject of this study with emphasis on ABI post exercise. ABI at rest and post exercise were measured in both legs of 20 patients with typical symptoms of IC. After 15 minutes of rest these measurements were repeated by another observer. Analysis according to Bland-Altman was performed on 40 paired leg measurements at rest and 40 paired leg measurements post exercise. The average ABI at rest for the first observer was 0.84 (standard deviation ±0.18) and for the second was 0.84 (±0.17). Post-exercise averages were 0.73 (±0.25) and 0.74 (±0.27), respectively. The standard deviation of the ABI difference between observers was 0.08 at rest and 0.15 post exercise. The interobserver variability of the ABI was 10% at rest and 21% post exercise. The interobserver variability post exercise is an important given when rules are defined about how the ABI post exercise translates into a more reliable and objective diagnosis of IC. [ABSTRACT FROM AUTHOR]

Full-field digital mammography (FFDM) has several potential benefits as compared with screen-film mammography (SFM) in mammography screening. Digital technology also opens for implementation of advanced applications, including computer-aided detection (CAD) and tomosynthesis. Phantom studies and experimental clinical studies have shown that FFDM is equal or slightly superior to SFM for detection and characterization of mammographic abnormalities. Despite obvious advantages, the conversion to digital mammography has been slower than anticipated, and not only due to higher costs. Until very recently, some countries did not even permit the use of digital mammography in breast cancer screening. The reason for this reluctant attitude was concern about lower spatial resolution and about using soft-copy reading. Furthermore, there was a lack of data supporting improved diagnostic accuracy using FFDM in a screening setting, since two pioneer trials both showed nonsignificantly lower cancer detection rate at FFDM. The 10 studies comparing FFDM and SFM in mammography screening published so far have shown divergent and rather conflicting results. Nevertheless, there is a rapid conversion to digital mammography in breast cancer screening in many western countries. The aim of this article is to give an updated review of these studies, discuss the conflicting findings, and draw some conclusions from the results. [ABSTRACT FROM AUTHOR]

Background: Although gross tumor volume (GTV) at the primary site can predict local control of head-and-neck squamous cell carcinoma (SCC) in patients who are treated with organ-preservation therapy, GTV assessment does not eliminate substantial interobserver variation. Purpose: To evaluate whether F-18-fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) fused imaging provides additional information for GTV assessment. Material and Methods: We obtained FDG-PET/CT fused images on 20 patients with head-and-neck SCC. All had undergone preoperative conventional workup, including contrast-enhanced CT and magnetic resonance imaging (MRI). The GTV of the primary tumors was designed by two independent observers who used routine clinical data. Observer A was a radiologist and observer B a radiation oncologist. GTV1 and GTV2 were designed without and with FDG-PET/CT, respectively. For geometric interobserver comparison, we calculated the concordance rate as the ratio of the intersection (Ax∩B) of the GTVs to their union (Ax∪B). Intermethod (GTV1 vs. GTV2) and interobserver (A vs. B) differences in the GTVs were assessed by Bland-Altman analysis and the Spearman rank-correlation test. The interobserver concordance rates for GTV1 and GTV2 were compared using a two-tailed paired-samples t test. Results: On FDG-PET/CT, all primary tumors were visualized. There was no systemic trend for a volume difference between GTV1 and GTV2. Although the 95% limits of agreement were wider for interobserver than intermethod differences, the 95% limits of interobserver agreement were narrower for GTV2 than GTV1. The mean interobserver concordance rate for GTV2 was higher than for GTV1 (54.5% vs. 39.1%, P=0.0002). Conclusion: FDG-PET/CT is a useful modality for consistent GTV assessment, which should not be used as a single modality but rather to obtain supplemental information in patients with head-and-neck SCC. [ABSTRACT FROM AUTHOR]

Significant intra- and interobserver variation has been reported for estimating the dimensions and the volume of the thyroid gland by conventional sonography in adults. This study aimed to assess the role of extended field-of-view (EFOV) sonography for evaluating the size of the thyroid gland. The mediolateral, anteroposterior, and craniocaudal diameters of both thyroid lobes as well as total thyroid volumes of 30 female patients with the clinical diagnosis of goiter were measured three times by three radiologists with the EFOV sonography technique. Based on these findings, the correlation between the measurements of different operators and different measurements of the same operator was investigated. The interobserver variations for craniocaudal diameters of the right and left thyroid lobes were 3.3% ± 1.9% (mean ± SD) and 2.8% ± 1.3% (mean ± SD), respectively (P = .012), which were lower than the variations calculated for transverse and mediolateral diameters. The interobserver variation for the calculation of the total glandular volume was 6.3% ± 3.8% (mean ± SD). The intraobserver variations for the three radiologists assessing the total thyroid volume were 4.9% ± 3.0%, 4.2% ± 2.4%, and 4.5% ± 1.7% (all mean ± SD), respectively (P = .521). EFOV sonography should be considered as an alternative technique for the dimension measurements of the thyroid gland, particularly in cases with goiter. [ABSTRACT FROM AUTHOR]

Purpose: To compare cancer detection rates of screen‐film (SFM) and full‐field digital mammography (FFDM) with soft‐copy reading in a screening program including the initial positive scores for interval cancers and cancers in the subsequent screening round, and to analyze the false‐negative FFDM interpretations. Material and Methods: Using a paired study design, 3683 women underwent SFM and FFDM in a population‐based screening program. Two standard views of each breast were acquired. The images were interpreted without previous films for comparison. Independent double reading using a 5‐point rating scale for probability of cancer was used for each modality. An examination was defined as positive if at least one of the two independent readers scored 2 or higher on the 5‐point rating scale. SFM‐positive cases were discussed in a SFM consensus meeting and FFDM‐positive cases in a separate FFDM consensus meeting before recall. The study population was followed for more than 2 years so that interval cancers and screen‐detected cancers in the subsequent screening round could be included. Cancer detection rates were compared using the McNemar test for paired proportions. The kappa statistic and Wilcoxon signed‐rank test for matched pairs were used for comparing rating scores. The reading time was recorded for all FFDM interpretations. Results: A total of 31 cancers (detection rate 0.84%) were diagnosed initially, of which SFM detected 28 and FFDM 23 (McNemar test P = 0.23, discordant pair 8 and 3). Two cancers with a positive score at initial SFM reading and three with a positive score at initial FFDM reading were dismissed at SFM and FFDM consensus meetings, respectively. The difference in cancer detection after recall (discordant pair 11 and 5) was not significant (McNemar test, P = 0.21). Of the 10 interval cancers and 16 screen‐detected cancers in the subsequent round, 3 had true‐positive SFM scores while 4 had true‐positive FFDM scores in the initial reading session. A total of 38 cancers therefore had a positive result at double reading at one or both modalities, 31 at SFM and 27 at FFDM (McNemar test, P = 0.48). Comparison of SFM and FFDM interpretations using the mean score for each case revealed no statistically significant difference between the two modalities (Wilcoxon signed‐rank test for matched pairs; P ‐value = 0.228). Two initial round cancers (one tumor found incidentally at work‐up for a mass proved to be a simple cyst with a positive score at FFDM but a negative score at SFM, and one tumor with positive score at SFM but negative score at FFDM due to positioning failure) were excluded from the further analysis. Excluding these two cancers from comparison, there were 31% (22 of 72) false‐negative SFM and 47% (34 of 72) false‐negative FFDM individual interpretations. The overall mean interpretation time for normal FFDM examinations was 45 s. For most false‐negative FFDM results, the reading time was shorter or longer than for normal examinations. The recorded FFDM interpretation time was noticeably short for several overlooked cancers manifesting as microcalcifications (ductal carcinoma in situ). Conclusion: There is no statistically significant difference in cancer detection rate between SFM and FFDM with soft‐copy reading in a mammography screening program. Analysis of cancers missed at FFDM with soft‐copy reading indicates that close attention has to be paid to systematic use of image display protocols. [ABSTRACT FROM AUTHOR]