Three-Dimensional Fast Spin Echo Pituitary MRI in Treatment-Naïve Cushing's Disease: Reduced Impact of Reader Experience and Increased Diagnostic Accuracy.

BACKGROUND: In patients with Cushing's disease, the preoperative identification of pituitary adenomas is crucial to treatment. However, increasing diagnostic accuracy remains an unresolved issue. PURPOSE: To evaluate the diagnostic accuracy and the impact of readers' experience regarding high-resolution contrast-enhanced magnetic resonance imaging (hrMRI) for identifying pituitary adenomas in comparison with conventional contrast-enhanced MRI (cMRI) and dynamic contrast-enhanced MRI (dMRI). STUDY TYPE: Retrospective. POPULATION: Sixty-five patients (median age, 39 years; interquartile range [IQR], 28-53 years; 60% females) with treatment-naïve Cushing's disease. FIELD STRENGTH/SEQUENCE: 3-T, seven fast spin echo sequences. ASSESSMENT: The diagnostic accuracies of identifying pituitary adenomas on cMRI, dMRI, combined cMRI and dMRI (cdMRI), and hrMRI were independently evaluated by six readers with three experience levels (high: >20 years, modest: 10-20 years, low: <10 years; two readers for each experience level). Readers were asked to localize the lesion, and measure its diameter on the sequence where identified. The reference standard was postoperative histopathology. The impact of readers' experience and interobserver agreement were assessed. Image quality was assessed using a 5-point Likert scale, including overall image quality, sharpness, and structural conspicuity. STATISTICAL TESTS: McNemar's test, Cochran's test, Wilcoxon signed-rank test, Mann-Whitney U test, and κ statistics for interobserver agreement. A P-value <0.05 was considered statistically significant. RESULTS: For identifying pituitary adenomas (median diameter, 5 mm; IQR, 4-5 mm), hrMRI had significantly higher sensitivity (87.7%-93.8%) than cMRI, dMRI, and cdMRI (52.3%-75.4%) for readers with different experience levels. The interobserver agreement was moderate (κ = 0.461-0.523). The sensitivity for hrMRI was comparable between readers with different experience levels (P = 0.371). All image quality scores on hrMRI were significantly higher than cMRI and dMRI (5.0 vs. 4.0). DATA CONCLUSION: For identifying pituitary adenomas in patients with treatment-naïve Cushing's disease, hrMRI may show high diagnostic accuracy and seems not to be affected by readers' experience. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Quantifying intraepithelial lymphocytes and subepithelial collagen band in microscopic colitis, extracting insights into the interrelationship of lymphocytic and collagenous colitis.

Microscopic colitis (MC) is the umbrella term for the conditions termed lymphocytic colitis (LC) and collagenous colitis (CC). LC with thickening of the subepithelial collagen band or CC with increased number of intraepithelial T- lymphocytes (IELs) is often seen in MC and may lead to difficulties in correct histological classification. We investigated the extent of overlapping features of CC and LC in 60 cases of MC by measuring the exact thickness of the subepithelial collagen band in Van Gieson stained slides and quantifying number of IELs in CD3 stained slides by digital image analysis. A thickened collagen band was observed in nine out of 29 cases with LC (31%) and an increased number of IELs in all 23 cases of CC (100%). There was no correlation between the thickness of the collagen band and number of IELs. Due to the increased number of IELs in all cases of CC we consider the lymphocytic inflammatory infiltration of the mucosa to be the essential histopathological feature of MC. However, although LC and CC are related due to the lymphocytic inflammation, the non-linear correlation of number of IELs and thickness of the collagenous band indicate differences in their pathogenesis.

Interobserver variation in the classification of thymic lesions including biopsies and resection specimens in an international digital microscopy panel.

AIMS: Thymic tumours are rare in routine pathology practice. Although the World Health Organization (WHO) classification describes a number of well-defined categories, the classification remains challenging. The aim of this study was to investigate the reproducibility of the WHO classification among a large group of international pathologists with expertise in thymic pathology and by using whole slide imaging to facilitate rapid diagnostic turnover. METHODS AND RESULTS: Three hundred and five tumours, consisting of 90 biopsies and 215 resection specimens, were reviewed with a panel-based virtual microscopy approach by a group of 13 pathologists with expertise in thymic tumours over a period of 6 years. The specimens were classified according to the WHO 2015 classification. The data were subjected to statistical analysis, and interobserver concordance (Fleiss kappa) was calculated. All cases were diagnosed within a time frame of 2 weeks. The overall level of agreement was substantial (κ = 0.6762), and differed slightly between resection specimens (κ = 0.7281) and biopsies (κ = 0.5955). When analysis was limited to thymomas only, and they were grouped according to the European Society for Medical Oncology Clinical Practice Guidelines into B2, B3 versus A, AB, B1 and B3 versus A, AB, B1, B2, the level of agreement decreased slightly (κ = 0.5506 and κ = 0.4929, respectively). Difficulties arose in distinguishing thymoma from thymic carcinoma. Within the thymoma subgroup, difficulties in distinction were seen within the B group. CONCLUSIONS: Agreement in diagnosing thymic lesions is substantial when they are assessed by pathologists with experience of these rare tumours. Digital pathology decreases the turnaround time and facilitates access to what is essentially a multinational resource. This platform provides a template for dealing with rare tumours for which expertise is sparse.

Validation of the AASLD recommendations for classification of oesophageal varices in clinical practice.

BACKGROUND & AIMS: The American Association for the Study of Liver Diseases recommends the use of a 2-grade classification system (small and large) to describe the size of oesophageal varices (OV). Data on observer agreement (OA) on this system are currently lacking. We aimed to evaluate this classification and compare it to the widely used 3-grade classification (grade 1 'small', grade 2 'medium', grade 3 'large') among operators of variable experience. METHODS: High-definition video recordings of 100 patients with cirrhosis were prospectively collected using standardised criteria. Nine observers of variable experience performed independent evaluations of the videos in random order. OV were scored using both systems. All assessments were repeated a year later by the same observers to assess intra-observer agreement. RESULTS: Interobserver agreement (all observers) using the 2-grade and the 3-grade system was k = 0.71 (95% CI: 0.64-0.78) and k = 0.73 (95% CI: 0.66-0.79) respectively. When using the 2-grade system, intra-observer agreement between hepatologists (n = 3), luminal gastroenterologists (n = 3) and trainee gastroenterologists (n = 3) was k = 0.89 (95% CI: 0.86-0.91), k = 0.72 (95% CI: 0.67-0.77), and k = 0.74 (95% CI: 0.67-0.8) respectively. With the 3-grade system; intra-observer agreement between the same three subgroups were k = 0.9 (95% CI: 0.87-0.92), k = 0.73 (95% CI: 0.68-0.78), k = 0.77 (95% CI: 0.71-0.82) respectively. CONCLUSIONS: There was no difference in OA between the 2-grade and 3-grade classification systems. Hepatologists had significantly higher levels of consistency in grading OV. This may have implications to create alternative training models for residents and fellows in the recognition and grading of OV.

Observer uncertainties of soft tissue-based patient positioning in IGRT.

PURPOSE: There remain uncertainties due to inter- and intraobserver variability in soft-tissue-based patient positioning even with the use of image-guided radiation therapy (IGRT). This study aimed to reveal observer uncertainties of soft-tissue-based patient positioning on cone-beam computed tomography (CBCT) images for prostate cancer IGRT. METHODS: Twenty-six patients (7-8 fractions/patient, total number of 204 fractions) who underwent IGRT for prostate cancer were selected. Six radiation therapists retrospectively measured prostate cancer location errors (PCLEs) of soft-tissue-based patient positioning between planning CT (pCT) and pretreatment CBCT (pre-CBCT) images after automatic bone-based registration. Observer uncertainties were evaluated based on residual errors, which denoted the differences between soft-tissue and reference positioning errors. Reference positioning errors were obtained as PCLEs of contour-based patient positioning between pCT and pre-CBCT images. Intraobserver variations were obtained from the difference between the first and second soft-tissue-based patient positioning repeated by the same observer for each fraction. Systematic and random errors of inter- and intraobserver variations were calculated in anterior-posterior (AP), superior-inferior (SI), and left-right (LR) directions. Finally, clinical target volume (CTV)-to-planning target volume (PTV) margins were obtained from systematic and random errors of inter- and intraobserver variations in AP, SI, and LR directions. RESULTS: Interobserver variations in AP, SI, and LR directions were 0.9, 0.9, and 0.5 mm, respectively, for the systematic error, and 1.8, 2.2, and 1.1 mm, respectively, for random error. Intraobserver variations were <0.2 mm in all directions. CTV-to-PTV margins in AP, SI, and LR directions were 3.5, 3.8, and 2.1 mm, respectively. CONCLUSION: Intraobserver variability was sufficiently small and would be negligible. However, uncertainties due to interobserver variability for soft-tissue-based patient positioning using CBCT images should be considered in CTV-to-PTV margins.

Impact of 3 Tesla MRI on interobserver agreement in clinically isolated syndrome: A MAGNIMS multicentre study.

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.

Comparison of radiographs, tomosynthesis and CT with metal artifact reduction for the detection of hip prosthetic loosening.

OBJECTIVES: To evaluate the diagnostic performance of digital tomosynthesis (DTS) for the diagnosis of hip prosthesis loosening (PL) compared with conventional radiographs and CT with metal artifact reduction (CT-MAR). METHODS: Forty-nine patients with painful hip prosthesis were prospectively included and underwent anteroposterior and lateral radiographs, anteroposterior DTS and CT-MAR of the hip. This study was approved by the local ethics committee, and all patients signed an informed consent form. Images were evaluated independently by two radiologists. Periprosthetic radiolucent lines wider than 2 mm found in two or more Gruen or De Lee and Charnley zones were considered diagnostic of PL. All cases of PL were confirmed surgically. Patients with a stable radiological follow-up for at least 1 year with an alternative cause for the symptoms or with no surgical evidence of PL were considered PL negative. RESULTS: There were 21 cases of PL, 9 unilateral and 12 bilateral. For both the acetabular and femoral sides, DTS had a specificity for PL detection similar to that of conventional radiographs and CT-MAR (98.5-100%, 96.9%-100% and 96.9-95.4% respectively for both readers) and a sensitivity similar to conventional radiographs (39.9-45.4% versus 33.3-51.5% for both readers) but lower than CT-MAR (84.85% for both readers). The interobserver agreement was 0.84 for CT-MAR, 0.53 for DTS and 0.39 for conventional radiographs. CONCLUSION: DTS has a similar diagnostic performance to radiographs for the diagnosis of PL with a better interobserver agreement. The sensitivity however remains lower than that of CT-MAR. KEY POINTS: • Plain radiograph is still the first imaging step when hip prosthesis loosening is suspected. • Interobserver agreement is better with digital tomosynthesis than radiographs. • Sensitivity of CT with state-of-the-art metal artifact reduction is superior to that of digital tomosynthesis.

Ankle Fracture Classification: An Innovative System for Describing Ankle Fractures.

A good classification system is important for clinical handoffs, research, and clinical treatment guidelines. A reliable classification system shows good interobserver and intraobserver agreement. This study analyzed the interobserver and intraobserver agreement of a descriptive system for ankle fractures and the Lauge-Hansen classification. Three groups of observers (experts, semiexperts, and novices) scored a total of 20 ankle radiographs. All ankle radiographs were classified according to the Lauge-Hansen and Danis-Weber classifications. The ankle fractures were subsequently reviewed in a descriptive manner for the following features: number of affected malleoli, type of fracture of the lateral and medial malleolus, and congruence of the ankle joint. After 2 weeks, the same set of radiographs were reviewed. For interobserver and intraobserver variability, the separate groups were used for analysis, and the Fleiss (multirater) κ values were calculated. The interobserver agreement for the Lauge-Hansen classification was moderate for the experts, fair for semiexperts, and slight for novices (κ = 0.45, κ = 0.37, and κ = 0.16). All factors of the descriptive system had better interobserver agreement than the Lauge-Hansen classification, except for the agreement on the type of fracture of the lateral malleolus. The intraobserver agreement of the Lauge-Hansen classification was substantial for the experts, moderate for the semiexperts, and fair for the novice observers (κ = 0.70, κ = 0.49, and κ = 0.26). The intraobserver agreement was better for all factors of the descriptive system compared with the Lauge-Hansen classification. The descriptive system presented in this study shows less variability between observers than the Lauge-Hansen classification. This system has clinical implications and is easy to use for clinicians with mixed levels of experience. It has the potential to improve clinical and research handoffs and overcome the limitations of current classification systems.

Factors to improve the interobserver agreement for gastric atrophy and intestinal metaplasia: consensus of definition and criteria.

AIMS: Intestinal metaplasia and atrophy of the gastric mucosa are associated with Helicobacter pylori infection and are considered premalignant lesions. The updated Sydney system is used for these parameters, but experienced pathologists and consensus processes are required for interobserver agreement. We sought to determine the influence of the consensus process on the assessment of intestinal metaplasia and atrophy. METHODS AND RESULTS: Two study sets were used: consensus and validation. The consensus set was circulated and five gastrointestinal pathologists evaluated them independently using the updated Sydney system. The consensus of the definitions was then determined at the first consensus meeting. The same set was recirculated to determine the effect of the consensus. The second consensus meeting was held to standardise the grading criteria and the validation set was circulated to determine the influence. Two additional circulations were performed to assess the maintainance of consensus and intraobserver variability. Interobserver agreement of intestinal metaplasia and atrophy was improved through the consensus process (intestinal metaplasia: baseline κ = 0.52 versus final κ = 0.68, P = 0.006; atrophy: baseline κ = 0.19 versus final κ = 0.43, P < 0.001). Higher interobserver agreement in atrophy was observed after consensus regarding the definition (pre-consensus: κ = 0.19 versus post-consensus: κ = 0.34, P = 0.001). There was improved interobserver agreement in intestinal metaplasia after standardisation of the grading criteria (pre-standardisation: κ = 0.56 versus post-standardisation: κ = 0.71, P = 0.010). CONCLUSIONS: This study suggests that interobserver variability regarding intestinal metaplasia and atrophy may result from lack of a precise definition and fine criteria, and can be reduced by consensus of definition and standardisation of grading criteria.

Interobserver variation in CD30 immunohistochemistry interpretation; consequences for patient selection for targeted treatment.

AIMS: CD30 immunohistochemistry (IHC) in malignant lymphoma is used for selection of patients in clinical trials using brentuximab vedotin, an antibody drug-conjugate targeting the CD30 molecule. For reliable implementation in daily practice and meaningful selection of patients for clinical trials, information on technical variation and interobserver reproducibility of CD30 immunohistochemistry (IHC) staining is required. METHODS AND RESULTS: We conducted a three-round reproducibility assessment of CD30 scoring for categorised frequency and intensity, including a technical validation, a 'live polling' pre- and post-instruction scoring round and a web-based round including individual scoring with additional IHC information to mimic daily diagnostic practice. Agreement in all three scoring rounds was poor to fair (κ = 0.12-0.35 for CD30-positive tumour cell percentage and κ = 0.16-0.41 for staining intensity), even when allowing for one category of freedom in percentage of tumour cell positivity (κ = 0.30-0.61). The first round with CD30 staining performed in five independent laboratories showed objective differences in staining intensity. In the second round, approximately half the pathologists changed their opinion on CD30 frequency after a discussion on potential pitfalls, highlighting hesitancy in decision-making. Using fictional cut-off points for percentage of tumour cell positivity, agreement was still suboptimal (κ = 0.35-0.60). CONCLUSIONS: Lack of agreement in cases with heterogeneous expression is shown to influence patient eligibility for treatment with brentuximab vedotin, both in clinical practice and within the context of clinical trials, and limits the potential predictive value of the relative frequency of CD30-positive neoplastic cells for clinical response.

Validation of a computerized algorithm to quantify fetal heart rate deceleration area.

INTRODUCTION: Reliability in visual cardiotocography interpretation is unsatisfying, which has led to the development of computerized cardiotocography. Computerized analysis is well established for antenatal fetal surveillance but has yet not performed sufficiently during labor. We aimed to investigate the capacity of a new computerized algorithm compared with visual assessment in identifying intrapartum fetal heart rate baseline and decelerations. MATERIAL AND METHODS: In all, 312 intrapartum cardiotocography tracings with variable decelerations were analyzed by the computerized algorithm and visually examined by two observers, blinded to each other and the computer analysis. The width, depth and area of each deceleration was measured. Four cases (>100 variable decelerations) were subjected to in-depth detailed analysis. The outcome measures were bias in seconds (width), beats per minute (depth), and beats (area) between computer and observers using Bland-Altman analysis. Interobserver reliability was determined by calculating intraclass correlation and Spearman rank analysis. RESULTS: The analysis (312 cases) showed excellent intraclass correlation (0.89-0.95) and very strong Spearman correlation (0.82-0.91). The detailed analysis of >100 decelerations in four cases revealed low bias between the computer and the two observers; width 1.4 and 1.4 seconds, depth 5.1 and 0.7 beats per minute, and area 0.1 and -1.7 beats. This was comparable to the bias between the two observers: 0.3 seconds (width), 4.4 beats per minute (depth) and 1.7 beats (area). The intraclass correlation was excellent (0.90-.98). CONCLUSION: A novel computerized algorithm for intrapartum cardiotocography analysis is as accurate as gold standard visual assessment, with high correlation and low bias.

Accuracy and interobserver agreement of retroareolar frozen sections in nipple-sparing mastectomies.

In the last decades, surgical treatment of breast cancer has enormously changed. As a result, nipple-sparing mastectomy (NSM) has evolved as an oncologically safe and cosmetic approach. NSM includes a subareolar frozen section to evaluate malignancy. We determined the accuracy of subareolar frozen section diagnosis, analyzed the discrepancy factor, and estimated the interobserver agreement of frozen section in NSM. A retrospective review of all NSMs at our institution from 2009 to 2015 was performed. Frozen sections were compared to the final diagnoses to analyze the accuracy of subareolar frozen sections. Discordant results were rigorously evaluated to identify discrepancy factors. Some cases were randomly chosen to assess the interobserver agreement (kappa) among pathologists. The agreement results were evaluated with and without knowledge of the tumor morphology. Among 34 NSMs, the frozen section false-negative and false-positive rate was 5.9% and 8.8%, respectively. The sensitivity and specificity was 77.8% and 88.0%, respectively. Sampling errors and diathermy artifacts explained our false-negative diagnoses. Freezing artifacts and an intraductal papilloma explained our false-positive diagnoses. The interobserver agreement between breast and general pathologists was 0.87 (p<0.0001) and 0.31 (p=0.0001), respectively. The interobserver agreement increased to 0.35 (p<0.0001) in general pathologists with knowledge of the tumor morphology. Subareolar frozen section showed to be a specific test with moderate sensitivity. Papillary lesions can mimic atypical cells and influence the frozen section interpretation. Frozen section in NSM had a better performance in breast pathologists (almost perfect) versus general pathologists (fair). Interobserver agreement may improve with knowledge of tumor morphology.

[Intraductal carcinoma of the prostate]. / Intraduktales Karzinom der Prostata.

For many tumor entities, especially in breast cancer, an intraductal carcinoma is generally perceived as a precursor lesion, which precedes the emergence of invasive carcinoma. Therefore, in addition to parameters of the invasive carcinoma, histological parameters of the intraductal component have always played an important role in therapy planning of breast cancer. This is different in prostate cancer and although the term "intraductal carcinoma" has long been propagated by some authors, its routine use remains rare and inconsistent. This is certainly not only due to the far simpler therapy options of prostate cancer, in which focal and organ-preserving therapies still play a subordinate role, but also due to substantial interobserver variation and our inconsistent perception of intraductal carcinomas. This article gives a brief overview of currently available literature on this topic and explains why intraductal carcinoma of the prostate deserves our attention. In contrast to breast cancer, intraductal carcinoma of the prostate usually represents a post-invasive lesion, in which an aggressive tumor exhibits spread into pre-existing ducts; however, in rare cases, intraductal carcinoma may represent a true precursor lesion.

Repeated biopsies in patients with prostate cancer on active surveillance: clinical implications of interobserver variation in histopathological assessment.

OBJECTIVE: To investigate the clinical implications of interobserver variation in the assessment of re-biopsies obtained during active surveillance (AS) of prostate cancer. PATIENTS AND METHODS: In all, 107 patients with low-risk prostate cancer with 93 diagnostic biopsy sets and 109 re-biopsy sets were included. The International Society of Urological Pathology 2005 Gleason scoring system was used for the histopathological assessment of all biopsies. Three different definitions of histopathological progression were applied. Unweighted and linear weighted Kappa (κ) statistics were used to compare the interobserver agreement. RESULTS: The overall Gleason score agreement was 68.8% with a weighted κ of 0.670. The interobserver agreement was 79.6% for meeting the AS selection criteria. According to the three progression definitions applied, overall agreement was between 80.7% and 89.0% with weighted κ values of 0.746-0.791. Treatment recommendations would have changed in up to 10.1% (95% confidence interval 5.4-17.7%) of the 109 re-biopsy sets. CONCLUSION: Kappa statistics showed strong agreement between the histological evaluations. However, up to 10% of patients on AS would receive a different treatment recommendation depending upon which histopathological evaluation of re-biopsies was used for treatment planning.

Interobserver variability of cervical cytology in HIV-infected women.

OBJECTIVES: Our objectives were to determine the reproducibility of cytological specimen interpretation between two pathologists in human immunodeficiency virus (HIV)-infected women (from the VIHGY, ANRS CO17 study of human papillomavirus genital pathology among HIV-positive women) and to analyse the improvement, if any, between conventional and liquid-based cytology (LBC) interpretations. MATERIALS AND METHODS: A sample of all abnormal and 40% of randomly selected normal Papanicolaou (Pap) tests was randomly ordered and read blindly by a second pathologist using the revised Bethesda terminology 2001. For both conventional and liquid-based preparations, unweighted and Cicchetti-Allison-weighted kappa and their 95% confidence intervals (CIs) were calculated. Kappa values were then compared using the Altman rule to classify the reproducibility of cytological specimen interpretation. RESULTS: Two hundred and seventy-seven conventional Pap tests were reviewed, including 79 abnormal and 10 unsatisfactory results. Overall agreement between the two observers was 78%, with an estimated Cicchetti-Allison-weighted kappa of 0.69 (95%CI, 0.61-0.77). The corresponding values for the 268 LBCs, including 123 abnormal and two unsatisfactory results, were 84% and 0.82 (95%CI, 0.76-0.87), respectively. The reproducibility of LBC interpretations was significantly higher than that of conventional preparations (P = 0.009) and, for both laboratories, the percentages of unsatisfactory results were significantly lower for LBC. CONCLUSION: In HIV-infected women in the combination antiretroviral therapy era, the strength of agreement was better for LBCs than for conventional preparations, with a lower percentage of unsatisfactory results. When available, LBC should be preferred because of its higher reproducibility.

The inter-observer and intra-observer reliability of the Paprosky femoral bone loss classification system.

The Paprosky classification provides a straightforward algorithm for defining bone loss and directing treatment for femoral revision. The purpose of this study was to test the inter-observer and intra-observer reliability of this system. Four arthroplasty surgeons reviewed radiographs of 205 consecutive femoral revisions. For each radiograph, the pattern of femoral bone loss was classified by Paprosky type on two separate occasions. A kappa value was used to calculate the reliability, which demonstrated an inter-observer reliability of 0.61, indicating substantial agreement between surgeons. The intra-observer reliability for each of the 4 participating surgeons was 0.81, 0.78, 0.76, and 0.75, indicating substantial to almost perfect agreement. There is substantial agreement among experienced arthroplasty surgeons when using the Paprosky Classification to characterize femoral bone loss.

A scoring system for grading corkscrew claws in dairy cattle.

Corkscrew claw (CC) in dairy cattle is increasingly reported in dairy herds. CC is a progressive deformity of the claw capsule with uncertain aetiology and pathogenesis. Genetics and specific environmental factors are suspected of contributing to the development of this irreversible condition. CC has been found in lame cows; however, the cause and effect has not been established. To perform analysis of risk factors, treatment and pathogenesis, a definition of severity scores is called for. The aim of this study was to measure and analyse CC characteristics from photos of cows' feet to describe and evaluate a scoring system for CC. Width of the visible part of the axial wall, degree of contact between the toe and the floor and angle of the distal part of the abaxial wall as a proxy for the deviation of the abaxial wall was measured from 393 pictures of CC. Based on the measurements on the claws, the parameter "width of the axial wall" was chosen to define the scores. The parameter was divided into three intervals to define either mild CC 0.3-2.0 cm, moderate CC 2.1-3.5 cm or severe CC>3.5 cm and correlation between the parameters; level of contact between the toe and the floor and the angle of the distal abaxial wall was evaluated. There was a significant positive linear correlation between width of the axial wall and angle of the distal part of the abaxial wall (r=0.91), the wider the axial wall, the more the abaxial wall deviated in the distal part. As the width of the axial wall increased the toe increasingly lost contact with the floor, this association was significant for mild CC and moderate CC but not for severe CC. The Interobserver agreement of the CC Scoring system was tested by 30 claw trimmers each scoring 32 cadaver feet and by 2 trained observers on 28 photos of feet using Cohen´s weighted kappa and showed substantial to almost perfect agreement between untrained and trained observers, respectively.

Interobserver variation in tumor delineation of liver metastases using Magnetic Resonance Imaging.

Background and purpose: Magnetic Resonance Imaging (MRI) guided stereotactic body radiotherapy (SBRT) of liver metastases is an upcoming high-precision non-invasive treatment. Interobserver variation (IOV) in tumor delineation, however, remains a relevant uncertainty for planning target volume (PTV) margins. The aims of this study were to quantify IOV in MRI-based delineation of the gross tumor volume (GTV) of liver metastases and to detect patient-specific factors influencing IOV. Materials and methods: A total of 22 patients with liver metastases from three primary tumor origins were selected (colorectal(8), breast(6), lung(8)). Delineation guidelines and planning MRI-scans were provided to eight radiation oncologists who delineated all GTVs. All delineations were centrally peer reviewed to identify outliers not meeting the guidelines. Analyses were performed both in- and excluding outliers. IOV was quantified as the standard deviation (SD) of the perpendicular distance of each observer's delineation towards the median delineation. The correlation of IOV with shape regularity, tumor origin and volume was determined. Results: Including all delineations, average IOV was 1.6 mm (range 0.6-3.3 mm). From 160 delineations, in total fourteen single delineations were marked as outliers after peer review. After excluding outliers, the average IOV was 1.3 mm (range 0.6-2.3 mm). There was no significant correlation between IOV and tumor origin or volume. However, there was a significant correlation between IOV and regularity (Spearman's ρs = -0.66; p = 0.002). Conclusion: MRI-based IOV in tumor delineation of liver metastases was 1.3-1.6 mm, from which PTV margins for IOV can be calculated. Tumor regularity and IOV were significantly correlated, potentially allowing for patient-specific margin calculation.

An interobserver reproducibility study on invasiveness of bladder cancer using virtual microscopy and heatmaps.

AIMS: The distinction between non-invasive (pTa) and invasive (pT1) non-muscle invasive bladder cancer (NMIBC) is subject to considerable interobserver variation. We aimed to generate a teaching set of images based on the diagnostic opinions of a panel of expert genitourinary pathologists. METHODS AND RESULTS: Twenty-five transurethral resection specimens initially reported as pT1 NMIBC from two university hospitals were selected on the basis of potential uncertainty of stromal invasion. Digitized slides were reviewed independently by a panel of eight genitourinary pathologists, who annotated any invasive area if present. Annotations were reviewed by the lead panel, and heatmaps of annotated areas were constructed. Reasons for discrepancies were analysed, and kappa scores were calculated to determine agreement among the eight panellists. Full agreement by the eight panellists was obtained in 11 of 25 cases (44%), with a multi-rater (Fleiss) kappa of 0.47 (P < 0.0001). After joint review of the seven discordant (agreement <75% of panellists) cases, consensus was obtained for six cases, and a teaching set of images was generated. CONCLUSIONS: Interobserver agreement among the panellists in the selected cases was moderate, but consensus could be reached in almost all cases. Heatmaps proved to be instrumental in generating a teaching set of images for standardization of histological criteria for NMIBC invasion.

Three-dimensional ultrasound improves the accuracy of diameter measurement of the residual sac in EVAR patients.

OBJECTIVES: Discrepancy between maximum diameters obtained with two-dimensional ultrasound and computed tomography (CT) after endovascular aneurysm repair (EVAR) is well known. The maximal diameter is ideally measured perpendicular to the centerline, a methodology so far only feasible with three-dimensional (3D) CT and magnetic resonance angiography (MRA). We aimed to investigate the agreement between 3D ultrasound and 3D CT and to determine reproducibility measures. METHODS: Prospective study comparing 3D ultrasound with 3D CT in 124 consecutive patients seen 3 or 12 month after EVAR. RESULTS: Replacing 2D with 3D ultrasound, the mean difference was improved from 6.0 mm to -1.3 mm (p < .001), and the range of variability was reduced from 9.4 mm to 6.6 mm (p = .009) using 3D CT as the gold standard. The mean difference between 3D ultrasound and 3D CT maximum diameter of the residual sac was -1.3 mm with upper and lower limits of agreement of 5.2 mm and -7.9 mm, respectively. Reproducibility measures of 3D ultrasound were ± 4 mm. CONCLUSION: 3D ultrasound correlate significantly better to 3D CT than the currently used 2D ultrasound method when assessing maximum diameter of the residual sac after EVAR, and reproducibility measures were within clinical acceptable values.