BACKGROUND: Inchworm sign is a finding on diffusion-weighted magnetic resonance imaging (DWI-MRI) and is used to better stratify T-staging in muscle invasive (MIBC) and non-muscle-invasive bladder cancer (NMIBC). An uninterrupted low submucosal signal on DWI, defined as inchworm sign (IS), indicates NMIBC.
OBJECTIVE: We aimed to define the diagnostic accuracy of IS in primary bladder cancer, as well as find agreement between the urologists and the radiologist.
METHODS: Between December 2018 and December 2020, we retrospectively analyzed 95 primary bladder cancer patients who had undergone multiparametric-MRI before transurethral resection. Patients with former bladder cancer history, tumors smaller than 10 mm, and MRI without proper protocol, as well as patients who did not attend follow-up, were excluded. In total, 71 patients\' images were evaluated by a genitourinary specialist radiologist and two urologists. Sensitivity, specificity, positive and negative predictive values of IS and VI-RADS in differentiating MIBC and NMIBC, and interreader agreement between the radiologist and urologists were analyzed.
RESULTS: During follow-up, 38 patients (53.5%) were IS-positive, while 33 patients (46.5%) were negative. Among the 33 patients with negative IS, 14 patients (42.4%) had MIBC. Meanwhile, two out of the 38 IS-positive patients (5.3%) had MIBC (p = 0.00). Sensitivity, specificity, and positive and negative predictive values of IS in predicting MIBC were 87.5%, 63.6%, 41.2%and 94.6%, respectively. The interobserver agreement between the urologists and radiologist was almost perfect ( K  = 0.802 and K  = 0.745).
CONCLUSIONS: The absence of IS on DWI is useful in differentiating MIBC from NMIBC. It is a simple finding that can be interpreted by urologists.

OBJECTIVE: The aims of our study were to analyze agreement among readers with different levels of expertise and diagnostic performance of individual and combined imaging signs for the diagnosis of adhesive capsulitis of the shoulder.
METHODS: In a retrospective study, contrast-enhanced shoulder MRIs of 60 patients with and 120 without clinically diagnosed adhesive capsulitis were evaluated by three readers independently. As non-enhanced imaging signs, readers evaluated signal intensity and thickness of the axillary recess capsule, thickness of the rotator interval capsule and the coracohumeral ligament as well as obliteration of subcoracoid fat. Furthermore, contrast enhancement of axillary recess and rotator interval capsule were evaluated. Data analysis included interreader reliability, ROC analysis, and logistic regression (p < 0.05).
RESULTS: Contrast-enhanced parameters showed substantially higher agreement among readers (ICC 0.79-0.80) than non-enhanced parameters (0.37-0.45). AUCs of contrast-enhanced signs (95.1-96.6%) were significantly higher (p < 0.01) than of non-enhanced imaging signs (61.5-85.9%) when considered individually. Combined evaluation of axillary recess signal intensity and thicknesses of axillary recess or rotator interval-when at least one of two signs was rated positive-increased accuracy compared to individual imaging signs, however not statistically significant.
CONCLUSIONS: Contrast-enhanced imaging signs show both distinctly higher agreement among readers and distinctly higher diagnostic performance compared to non-enhanced imaging signs based on the imaging protocol used in this study. Combined evaluation of parameters showed a tendency to increase discrimination; however, the effect on diagnosis of ACS was not statistically significant.

To evaluate interreader agreement on pelvic multiparametric magnetic resonance imaging (mpMRI) interpretation among radiologists using a structured reporting tool based on the METastasis Reporting and Data System for Prostate Cancer (MET-RADS-P) guidelines.
A structured report for follow-up pelvic mpMRI for advanced prostate cancer (APC) patients was formulated based on MET-RADS-P guidelines. In total, 163 paired pelvic mpMRI examinations were performed from December 2017 to February 2021 on 105 patients with APC. These were retrospectively reviewed by two senior and two junior radiologists for metastatic lesion detection and were categorized by these readers using primary/secondary response assessment categories (RACs), with and without the structured report. Interreader agreement regarding metastasis detection and RAC scores was evaluated with Cohen\'s kappa and weighted Cohen\'s kappa statistics (K), respectively.
The two senior radiologists showed higher agreement with the reference standard for metastasis detection using the structured report (S1: K = 0.83; S2: K = 0.73) compared with the conventional report (S1: K = 0.72; S2: K = 0.61). Junior radiologists showed similar results (J1: 0.66 vs. 0.59; J2: 0.65 vs. 0.57). The overall agreement between the two senior radiologists was excellent for the primary RAC pattern using the structured reports (K = 0.81) and was substantial for secondary RAC categorization (K = 0.75). The interreader agreement of the two junior radiologists was substantial for both primary and secondary RAC values (K = 0.76, 0.68).
Good interreader agreement was found for the follow-up assessment of APC patients between radiologists, where the pelvic mpMRI was reported using MET-RADS-P guidelines. This improvement applied to both metastatic lesion detection and qualitative RAC assessment.

BACKGROUND: Interpretation of high-resolution CT images plays an important role in the diagnosis and management of interstitial lung diseases. However, interreader variation may exist due to varying levels of training and expertise. This study aims to evaluate interreader variation and the role of thoracic radiology training in classifying interstitial lung disease (ILD).
METHODS: This is a retrospective study where seven physicians (radiologists, thoracic radiologists, and a pulmonologist) classified the subtypes of ILD of 128 patients from a tertiary referral center, all selected from the Interstitial Lung Disease Registry which consists of patients from November 2014 to January 2021. Each patient was diagnosed with a subtype of interstitial lung disease by a consensus diagnosis from pathology, radiology, and pulmonology. Each reader was provided with only clinical history, only CT images, or both. Reader sensitivity and specificity and interreader agreements using Cohen\'s κ were calculated.
RESULTS: Interreader agreement based only on clinical history, only on radiologic information, or combination of both was most consistent amongst readers with thoracic radiology training, ranging from fair (Cohen\'s κ: 0.2-0.46), moderate to almost perfect (Cohen\'s κ: 0.55-0.92), and moderate to almost perfect (Cohen\'s κ: 0.53-0.91) respectively. Radiologists with any thoracic training showed both increased sensitivity and specificity for NSIP as compared to other radiologists and the pulmonologist when using only clinical history, only CT information, or combination of both (p < 0.05).
CONCLUSIONS: Readers with thoracic radiology training showed the least interreader variation and were more sensitive and specific at classifying certain subtypes of ILD.
UNASSIGNED: Thoracic radiology training may improve sensitivity and specificity in classifying ILD based on HRCT images and clinical history.

BACKGROUND: Magnetic resonance imaging (MRI) is recommended by the European Urology Association guidelines as the standard modality for imaging-guided biopsy. Recently positron emission tomography with prostate-specific membrane antigen (PSMA PET) has shown promising results as a tool for this purpose. The aim of this study was to compare the accuracy of positron emission tomography with prostate-specific membrane antigen/magnetic resonance imaging (PET/MRI) using the gallium-labeled prostate-specific membrane antigen (68Ga-PSMA-11) and multiparametric MRI (mpMRI) for pre-biopsy tumour localization and interreader agreement for visual and semiquantitative analysis. Semiquantitative parameters included apparent diffusion coefficient (ADC) and maximum lesion diameter for mpMRI and standardized uptake value (SUVmax) and PSMA-positive volume (PSMAvol) for PSMA PET/MRI.
RESULTS: Sensitivity and specificity were 61.4% and 92.9% for mpMRI and 66.7% and 92.9% for PSMA PET/MRI for reader one, respectively. RPE was available in 23 patients and 41 of 47 quadrants with discrepant findings. Based on RPE results, the specificity for both imaging modalities increased to 98% and 99%, and the sensitivity improved to 63.9% and 72.1% for mpMRI and PSMA PET/MRI, respectively. Both modalities yielded a substantial interreader agreement for primary tumour localization (mpMRI kappa = 0.65 (0.52-0.79), PSMA PET/MRI kappa = 0.73 (0.61-0.84)). ICC for SUVmax, PSMAvol and lesion diameter were almost perfect (≥ 0.90) while for ADC it was only moderate (ICC = 0.54 (0.04-0.78)). ADC and lesion diameter did not correlate significantly with Gleason score (ρ = 0.26 and ρ = 0.16) while SUVmax and PSMAvol did (ρ =  - 0.474 and ρ =  - 0.468).
CONCLUSIONS: PSMA PET/MRI has similar accuracy and reliability to mpMRI regarding primary prostate cancer (PCa) localization. In our cohort, semiquantitative parameters from PSMA PET/MRI correlated with tumour grade and were more reliable than the ones from mpMRI.

OBJECTIVE: To evaluate the interreader variability in prostate and seminal vesicle (SV) segmentation on T2w MRI.
METHODS: Six readers segmented the peripheral zone (PZ), transitional zone (TZ) and SV slice-wise on axial T2w prostate MRI examinations of n = 80 patients. Twenty different similarity scores, including dice score (DS), Hausdorff distance (HD) and volumetric similarity coefficient (VS), were computed with the VISCERAL EvaluateSegmentation software for all structures combined and separately for the whole gland (WG = PZ + TZ), TZ and SV. Differences between base, midgland and apex were evaluated with DS slice-wise. Descriptive statistics for similarity scores were computed. Wilcoxon testing to evaluate differences of DS, HD and VS was performed.
RESULTS: Overall segmentation variability was good with a mean DS of 0.859 (±SD = 0.0542), HD of 36.6 (±34.9 voxels) and VS of 0.926 (±0.065). The WG showed a DS, HD and VS of 0.738 (±0.144), 36.2 (±35.6 vx) and 0.853 (±0.143), respectively. The TZ showed generally lower variability with a DS of 0.738 (±0.144), HD of 24.8 (±16 vx) and VS of 0.908 (±0.126). The lowest variability was found for the SV with DS of 0.884 (±0.0407), HD of 17 (±10.9 vx) and VS of 0.936 (±0.0509). We found a markedly lower DS of the segmentations in the apex (0.85 ± 0.12) compared to the base (0.87 ± 0.10, p < 0.01) and the midgland (0.89 ± 0.10, p < 0.001).
CONCLUSIONS: We report baseline values for interreader variability of prostate and SV segmentation on T2w MRI. Variability was highest in the apex, lower in the base, and lowest in the midgland.

PET using radiolabeled prostate-specific membrane antigen (PSMA) is now being more widely adopted as a valuable tool to evaluate patients with prostate cancer (PC). Recently, 3 different criteria for interpretation of PSMA PET were published: the European Association of Nuclear Medicine (EANM) criteria, the Prostate Cancer Molecular Imaging Standardized Evaluation criteria, and the PSMA Reporting and Data System. We compared these 3 criteria in terms of interreader, intrareader, and intercriteria agreement. Methods: Data from 104 patients prospectively enrolled in research protocols at our institution were retrospectively reviewed. The cohort consisted of 2 groups: 47 patients (mean age, 64.2 y old) who underwent Glu-NH-CO-NH-Lys-(Ahx)-[68Ga(HBED-CC)] (68Ga-PSMA11) PET/MRI for initial staging of biopsy-proven intermediate- or high-risk PC, and 57 patients (mean age, 70.5 y old) who underwent 68Ga-PSMA11 PET/CT because of biochemically recurrent PC. Three nuclear medicine physicians independently evaluated all 68Ga-PSMA11 PET/MRI and PET/CT studies according to the 3 interpretation criteria. Two of them reevaluated all studies 6 mo later in the same manner and masked to the initial reading. The Gwet agreement coefficient was calculated to evaluate interreader, intrareader, and intercriteria agreement based on the following sites: local lesion (primary tumor or prostate bed after radical prostatectomy), lymph node metastases, and other metastases. Results: In the PET/MRI group, interreader, intrareader, and intercriteria agreement ranged from substantial to almost perfect for any site according to all 3 criteria. In the PET/CT group, interreader agreement ranged from substantial to almost perfect except for judgment of distant metastases based on the PSMA Reporting and Data System (Gwet agreement coefficient, 0.57; moderate agreement), in which the most frequent cause of disagreement was lung nodules. Intrareader agreement ranged from substantial to almost perfect for any site according to all 3 criteria. Intercriteria agreement for each site was also substantial to almost perfect. Conclusion: Although the 3 published criteria have good interreader and intrareader reproducibility in evaluating 68Ga-PSMA11 PET, there are some factors causing interreader disagreement. Further work is needed to address this issue.

To estimate the diagnostic accuracy of conventional 18F-FDG PET/CT of cranial arteries in the diagnosis of giant cell arteritis (GCA).
The study was a retrospective case-control study. The reference diagnosis was fulfillment of the 1990 ACR criteria for GCA. All patients had new-onset GCA. Conventional 18F-FDG PET/CT was performed before glucocorticoid treatment. Controls were age- and sex-matched patients with a previous history of malignant melanoma (MM) undergoing surveillance PET/CT >6 months after MM resection. PET images were evenly cropped to include only head and neck and were assessed in random order by four nuclear medicine physicians blinded to reference diagnosis. Temporal (TA), maxillary (MA) and vertebral (VA) arteries were visually rated for 18F-FDG uptake. Interreader agreement was evaluated by Fleiss kappa.
A total of 44 patients and 44 controls were identified. In both groups, the mean age was 69 years (p = 0.45) and 25/44 were women. 35/41 GCA patients were temporal artery biopsy positive (TAB). Considering only FDG uptake in TA and/or MA, diagnostic sensitivity and specificity was 64 and 100%. Including VA, sensitivity increased to 82% and specificity remained 100%. Interreader agreement was 91% and Fleiss kappa 0.82 for the PET diagnosis based on the cranial arteries.
Conventional 18F-FDG PET/CT is an accurate and reliable tool to diagnose cranial arteritis in glucocorticoid-naïve GCA patients. The high diagnostic specificity suggests that TAB can be omitted in patients with 18F-FDG uptake in cranial arteries. 18F-FDG PET/CT performed in patients with suspected vasculitis should always include the head and neck.

UNASSIGNED: Electrographic seizures in critically ill patients are often equivocal. In this study, we sought to determine the diagnostic accuracy of electrographic seizure annotation in adult intensive care units (ICUs) and to identify affecting factors.
UNASSIGNED: To investigate diagnostic accuracy, interreader agreement (IRA) measures were derived from 5,769 unequivocal and 6,263 equivocal seizure annotations by five experienced electroencephalogram (EEG) readers after reviewing 74 days of EEGs from 50 adult ICU patients. Factors including seizure equivocality (unequivocal vs. equivocal) and laterality (generalized, partial, or bilaterally independent), cyclicity (cyclic vs. noncyclic), persistency (occurrence of status epilepticus), and patient consciousness level (coma vs. noncoma) were further investigated for their influence on IRA measures.
UNASSIGNED: On average, 70% of seizures marked by a reference reader overlapped, at least in part, with those marked by a test reader (any-overlap sensitivity, AO-Sn). Agreed seizure duration between reader pairs (overlap-integral sensitivity, OI-Sn) was 62%, while agreed nonseizure duration (overlap-integral specificity, OI-Sp) was 99%. A test reader would annotate one additional seizure not overlapping with a reference reader\'s annotation in every 11.7 h of EEG, that is, the false-positive rate (FPR) was 0.0854/h. Classifying seizure patterns into unequivocal and equivocal improved specificity and FPR (unequivocal patterns) but compromised sensitivity only for equivocal patterns. Sensitivity of all and unequivocal annotations was higher for patients with status epilepticus. Specificity was higher for partial than for bilaterally independent unequivocal seizure patterns, and lower for cyclic all seizure patterns.
UNASSIGNED: Diagnosing electrographic seizures in critically ill adults is highly specific and moderately sensitive. Improved criteria for diagnosing electrographic seizures in the ICU are needed.

OBJECTIVE: to simultaneously evaluate interreader agreement and diagnostic accuracy in the of PI-RADS v2 and compare it to v1.
METHODS: A total of 67 patients (median age 65.3 y, range 51.2-78.2 y; PSA 6.8μg/L, 0.2-33μg/L) undergoing MRI of the prostate and subsequent transperineal template biopsy within ≤6 months from MRI were included. Four readers from two institutions evaluated the likelihood of prostate cancer using PI-RADS v1 and v2 in two separate reading sessions ≥3 months apart. Interreader agreement was assessed for each pulse-sequence and for total PI-RADS scores using the intraclass correlation coefficient (ICC). Differences were considered significant for non-overlapping 95%-confidence intervals. Diagnostic accuracy was assessed with the area under the receiver operating characteristic curve (AZ). A p-value <0.05 was considered statistically significant.
RESULTS: Interreader agreement for DCE-scores was good in v2 (ICC2=0.70; 95% CI: 0.66-0.74) and slightly lower in v1 (ICC1=0.64, 0.59-0.69). Agreement for DWI scores (ICC1=0.77, ICC2=0.76) as well as final PI-RADS scores per quadrant were nearly identical (ICC1=ICC2=0.71). Diagnostic accuracy showed no significant differences (p=0.09-0.93) between v1 and v2 in any of the readers (range: AZ=0.78-0.88).
CONCLUSIONS: PI-RADS scores show similar interreader agreement in v2 and v1 at comparable diagnostic performance. The simplification of the DCE interpretation in v2 might slightly improve agreement while not negatively affecting diagnostic performance.