Reliability of CT Enterography for Describing Fibrostenosing Crohn Disease.

Background Standardized methods to measure and describe Crohn disease strictures at CT enterography are needed to guide clinical decision making and for use in therapeutic studies. Purpose To assess the reliability of CT enterography features to describe Crohn disease strictures and their correlation with stricture severity. Materials and Methods A retrospective study was conducted in 43 adult patients with symptomatic terminal ileal Crohn disease strictures who underwent standard-of-care CT enterography at a tertiary care center at the Cleveland Clinic between January 2008 and August 2016. After training on standardized definitions, four abdominal radiologists blinded to all patient information assessed imaging features (seven continuous measurements and nine observations) of the most distal ileal stricture in two separate sessions (separated by ≥2 weeks) in random order. Features with an interrater intraclass correlation coefficient (ICC) of 0.41 or greater (ie, moderate reliability or better) were considered reliable. Univariable and multivariable linear regression analysis identified reliable features associated with a visual analog scale of overall stricture severity. Significant reliable features were assessed as components of a CT enterography-based model to quantitate stricture severity. Results Examinations in 43 patients (mean age, 52 years ± 16 [SD]; 23 female) were evaluated. Five continuous measurements and six observations demonstrated at least moderate interrater reliability (interrater ICC range, 0.42 [95% CI: 0.25, 0.57] to 0.80 [95% CI: 0.67, 0.88]). Of these, 10 were univariably associated with stricture severity, and three continuous measurements-stricture length (interrater ICC, 0.64 [95% CI: 0.42, 0.81]), maximal associated small bowel dilation (interrater ICC, 0.80 [95% CI: 0.67, 0.88]), and maximal stricture wall thickness (interrater ICC, 0.50 [95% CI: 0.34, 0.62])-were independently associated (P value range, <.001 to .003) with stricture severity in a multivariable model. These three measurements were used to derive a well-calibrated (optimism-adjusted calibration slope = 1.00) quantitative model of stricture severity. Conclusion Standardized CT enterography measurements and observations can reliably describe terminal ileal Crohn disease strictures. Stricture length, maximal associated small bowel dilation, and maximal stricture wall thickness are correlated with stricture severity. © RSNA, 2024 Supplemental material is available for this article. See also the article by Rieder et al in this issue. See also the editorial by Galgano and Summerlin in this issue.

Reliability of MR Enterography Features for Describing Fibrostenosing Crohn Disease.

Background Clinical decision making and drug development for fibrostenosing Crohn disease is constrained by a lack of imaging definitions, scoring conventions, and validated end points. Purpose To assess the reliability of MR enterography features to describe Crohn disease strictures and determine correlation with stricture severity. Materials and Methods A retrospective study of patients with symptomatic terminal ileal Crohn disease strictures who underwent MR enterography at tertiary care centers (Cleveland Clinic: September 2013 to November 2020; Mayo Clinic: February 2008 to March 2019) was conducted by using convenience sampling. In the development phase, blinded and trained radiologists independently evaluated 26 MR enterography features from baseline and follow-up examinations performed more than 6 months apart, with no bowel resection performed between examinations. Follow-up examinations closest to 12 months after baseline were selected. Reliability was assessed using the intraclass correlation coefficient (ICC). In the validation phase, after five features were redefined, reliability was re-estimated in an independent convenience sample using baseline examinations. Multivariable linear regression analysis identified features with at least moderate interrater reliability (ICC ≥0.41) that were independently associated with stricture severity. Results Ninety-nine (mean age, 40 years ± 14 [SD]; 50 male) patients were included in the development group and 51 (mean age, 45 years ± 16 [SD]; 35 female) patients were included in the validation group. In the development group, nine features had at least moderate interrater reliability. One additional feature demonstrated moderate reliability in the validation group. Stricture length (ICC = 0.85 [95% CI: 0.75, 0.91] and 0.91 [95% CI: 0.75, 0.96] in development and validation phase, respectively) and maximal associated small bowel dilation (ICC = 0.74 [95% CI: 0.63, 0.80] and 0.73 [95% CI: 0.58, 0.87] in development and validation group, respectively) had the highest interrater reliability. Stricture length, maximal stricture wall thickness, and maximal associated small bowel dilation were independently (regression coefficients, 0.09-3.97; P < .001) associated with stricture severity. Conclusion MR enterography definitions and scoring conventions for reliably assessing features of Crohn disease strictures were developed and validated, and feature correlation with stricture severity was determined. © RSNA, 2024 Supplemental material is available for this article. See also the article by Rieder and Ma et al in this issue. See also the editorial by Galgano and Summerlin in this issue.

Quantitative Magnetic Resonance Imaging (qMRI) of the Small Bowel in Crohn's Disease: State-of-the-Art and Future Directions.

Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract in which repeated episodes of acute inflammation may lead to long-term bowel damage. Cross-sectional imaging is used in conjunction with endoscopy to diagnose and monitor disease and detect complications. Magnetic resonance imaging (MRI) has demonstrable utility in evaluating inflammatory activity. However, subjective interpretation of conventional MR sequences is limited in its ability to fully phenotype the underlying histopathological processes in chronic disease. In particular, conventional MRI can be confounded by the presence of mural fibrosis and muscle hypertrophy, which can mask or sometimes mimic inflammation. Quantitative MRI (qMRI) methods provide a means to better differentiate mural inflammation from fibrosis and improve quantification of these processes. qMRI may also provide more objective measures of disease activity and enable better tailoring of treatment. Here, we review quantitative MRI methods for imaging the small bowel in CD and consider the path to their clinical translation. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Volumetric measurement of terminal ileal Crohn's disease by magnetic resonance enterography: a feasibility study.

OBJECTIVES: Magnetic resonance enterography (MRE) interpretation of Crohn's disease (CD) is subjective and uses 2D analysis. We evaluated the feasibility of volumetric measurement of terminal ileal CD on MRE compared to endoscopy and sMARIA, and the responsiveness of volumetric changes to biologics. METHODS: CD patients with MRE and contemporaneous CD endoscopic index of severity-scored ileocolonoscopy were included. A centreline was placed through the terminal ileum (TI) lumen defining the diseased bowel length on the T2-weighted non-fat saturated sequence, used by two radiologists to independently segment the bowel wall to measure volume (phase 1). In phase 2, we measured disease volume in patients treated with biologics, who had undergone pre- and post-treatment MRE, with treatment response classified via global physician assessment. RESULTS: Phase 1 comprised 30 patients (median age 29 (IQR 24, 34) years). Phase 2 included 12 patients (25 years (22, 38)). In phase 1, the mean of the radiologist-measured volumes was used for analysis. The median disease volume in those with endoscopically active CD was 20.9 cm3 (IQR 11.3, 44.0) compared to 5.7 cm3 (2.9, 9.8) with normal endoscopy. The mean difference in disease volume between the radiologists was 3.0 cm3 (limits of agreement -21.8, 15.9). The median disease volume of patients with active CD by sMARIA was 15.0 cm3 (8.7, 44.0) compared to 2.85 cm3 (2.6, 3.1) for those with inactive CD. Pre- and post-treatment median disease volumes were 28.5 cm3 (26.4, 31.2), 11 cm3 (4.8, 16.6), respectively in biological responders, vs 26.8 cm3 (12.3, 48.7), 40.1 cm3 (10, 56.7) in non-responders. CONCLUSION: Volumetric measurement of terminal ileal CD by MRE is feasible, related to endoscopy and sMARIA activity, and responsive to biologics. CLINICAL RELEVANCE STATEMENT: Measuring the whole volume of diseased bowel on MRE in CD is feasible, related to how biologically active the disease is when assessed by endoscopy and by existing MRE activity scores, and is sensitive to treatment response. KEY POINTS: MRE reporting for CD is subjective and uses 2D images rather than assessing the full disease volume. Volumetric measurement of CD relates to endoscopic activity and shows reduced disease volumes in treatment responders. This technique is an objective biomarker that can assess disease activity and treatment response, warranting validation.

Multivariable prognostic modelling to improve prediction of colorectal cancer recurrence: the PROSPeCT trial.

OBJECTIVE: Improving prognostication to direct personalised therapy remains an unmet need. This study prospectively investigated promising CT, genetic, and immunohistochemical markers to improve the prediction of colorectal cancer recurrence. MATERIAL AND METHODS: This multicentre trial (ISRCTN 95037515) recruited patients with primary colorectal cancer undergoing CT staging from 13 hospitals. Follow-up identified cancer recurrence and death. A baseline model for cancer recurrence at 3 years was developed from pre-specified clinicopathological variables (age, sex, tumour-node stage, tumour size, location, extramural venous invasion, and treatment). Then, CT perfusion (blood flow, blood volume, transit time and permeability), genetic (RAS, RAF, and DNA mismatch repair), and immunohistochemical markers of angiogenesis and hypoxia (CD105, vascular endothelial growth factor, glucose transporter protein, and hypoxia-inducible factor) were added to assess whether prediction improved over tumour-node staging alone as the main outcome measure. RESULTS: Three hundred twenty-six of 448 participants formed the final cohort (226 male; mean 66 ± 10 years. 227 (70%) had ≥ T3 stage cancers; 151 (46%) were node-positive; 81 (25%) developed subsequent recurrence. The sensitivity and specificity of staging alone for recurrence were 0.56 [95% CI: 0.44, 0.67] and 0.58 [0.51, 0.64], respectively. The baseline clinicopathologic model improved specificity (0.74 [0.68, 0.79], with equivalent sensitivity of 0.57 [0.45, 0.68] for high vs medium/low-risk participants. The addition of prespecified CT perfusion, genetic, and immunohistochemical markers did not improve prediction over and above the clinicopathologic model (sensitivity, 0.58-0.68; specificity, 0.75-0.76). CONCLUSION: A multivariable clinicopathological model outperformed staging in identifying patients at high risk of recurrence. Promising CT, genetic, and immunohistochemical markers investigated did not further improve prognostication in rigorous prospective evaluation. CLINICAL RELEVANCE STATEMENT: A prognostic model based on clinicopathological variables including age, sex, tumour-node stage, size, location, and extramural venous invasion better identifies colorectal cancer patients at high risk of recurrence for neoadjuvant/adjuvant therapy than stage alone. KEY POINTS: Identification of colorectal cancer patients at high risk of recurrence is an unmet need for treatment personalisation. This model for recurrence, incorporating many patient variables, had higher specificity than staging alone. Continued optimisation of risk stratification schema will help individualise treatment plans and follow-up schedules.

A global consensus on the definitions, diagnosis and management of fibrostenosing small bowel Crohn's disease in clinical practice.

Fibrostenosis of the small bowel is common in patients with Crohn's disease. No consensus recommendations on definition, diagnosis and management in clinical practice are currently available. In this Consensus Statement, we present a clinical practice RAND/UCLA appropriateness study on the definition, diagnosis and clinical management of fibrostenosing Crohn's disease. It was conducted by a panel of 28 global experts and one patient representative. Following a systematic literature review, 526 candidate items grouped into 136 questions were generated and subsequently evaluated for appropriateness. Strictures are best defined as wall thickening, luminal narrowing and prestenotic dilation. Cross-sectional imaging is required for accurate diagnosis of fibrostenosing Crohn's disease, and it is recommended before making treatment decisions. It should also assess the degree of inflammation in the bowel wall. Multiple options for medical anti-inflammatory, endoscopic and surgical therapies were suggested, including follow-up strategies following therapy. This Consensus Statement supports clinical practice through providing guidance on definitions, diagnosis and therapeutic management of patients with fibrostenosing small bowel Crohn's disease.

Development of a multimodal geomarker pipeline to assess the impact of social, economic, and environmental factors on pediatric health outcomes.

OBJECTIVES: We sought to create a computational pipeline for attaching geomarkers, contextual or geographic measures that influence or predict health, to electronic health records at scale, including developing a tool for matching addresses to parcels to assess the impact of housing characteristics on pediatric health. MATERIALS AND METHODS: We created a geomarker pipeline to link residential addresses from hospital admissions at Cincinnati Children's Hospital Medical Center (CCHMC) between July 2016 and June 2022 to place-based data. Linkage methods included by date of admission, geocoding to census tract, street range geocoding, and probabilistic address matching. We assessed 4 methods for probabilistic address matching. RESULTS: We characterized 124 244 hospitalizations experienced by 69 842 children admitted to CCHMC. Of the 55 684 hospitalizations with residential addresses in Hamilton County, Ohio, all were matched to 7 temporal geomarkers, 97% were matched to 79 census tract-level geomarkers and 13 point-level geomarkers, and 75% were matched to 16 parcel-level geomarkers. Parcel-level geomarkers were linked using our exact address matching tool developed using the best-performing linkage method. DISCUSSION: Our multimodal geomarker pipeline provides a reproducible framework for attaching place-based data to health data while maintaining data privacy. This framework can be applied to other populations and in other regions. We also created a tool for address matching that democratizes parcel-level data to advance precision population health efforts. CONCLUSION: We created an open framework for multimodal geomarker assessment by harmonizing and linking a set of over 100 geomarkers to hospitalization data, enabling assessment of links between geomarkers and hospital admissions.

Integrating person-centered care into dental education: An oral medicine perspective.

Dental education is moving toward models of education and care that are person-centered. The purpose of this article is to explore and describe the teaching and patient care model (the attending-based model) used for the past 50 years in the oral medicine department at one dental education institution. This article briefly discusses how this teaching model promotes person-centered care and the biopsychosocial model, while highlighting some of the barriers, benefits, and opportunities to wider adoption in dental education.

Influence of diffusion weighted imaging and contrast enhanced T1 sequences on the diagnostic accuracy of magnetic resonance enterography for Crohn's disease.

OBJECTIVES: To evaluate the additional diagnostic benefit of diffusion weighted imaging (DWI) and contrast enhanced (CE) images during MR enterography (MRE) of Crohn's disease. METHODS: Datasets from 73 patients (mean age 32; 40 male) (28 new-diagnosis, 45 relapsed) were read independently by two radiologists selected from a pool of 13. Radiologists interpreted datasets using three sequential sequence blocks: (1) T2 weighted and steady state free precession gradient echo (SSFP) images alone (T2^); (2) T2 weighted and SSFP images with DWI (T2 + DWI^) and; (3) T2 weighted images, SSFP, DWI and post-contrast enhanced (CE) T1 images (T2 + DWI + CE^), documenting presence, location, and activity of small bowel disease. For each sequence block, sensitivity and specificity (readers combined) was calculated against an outcome-based construct reference standard. RESULTS: 59/73 patients had small bowel disease. Per-patient sensitivity for disease detection was essentially identical (80 % [95 % CI 72, 86], 81 % [73,87], and 79 % [71,86] for T2^, T2 + DWI^and T2 + DWI + CE^respectively). Specificity was identical (82 % [64 to 92]). Per patient sensitivity for disease extent was 56 % (47,65), 56 % (47,65) and 52 % (43 to 61) respectively, and specificity was 82 % (64 to 92) for all blocks. Sensitivity for active disease was 97 % (90,99), 97 % (90,99) and 98 % (92,99), and specificity was also comparable between all sequence combination reads. Results were consistent across segments and newly diagnosed/relapse patients. CONCLUSION: There is no additional diagnostic benefit of adding either DWI or CE to T2 FSE and SSFP sequences for evaluating small bowel Crohn's disease, suggesting MRE protocols can be simplified safely.

Systematic review: Defining, diagnosing and monitoring small bowel strictures in Crohn's disease on intestinal ultrasound.

BACKGROUND: Stricturing Crohn's disease (CD) occurs most commonly in the terminal ileum and poses a clinical problem. Cross-sectional imaging modalities such as intestinal ultrasound (IUS), computed tomography enterography (CTE), and magnetic resonance enterography (MRE) allow for assessment of the entire bowel wall and associated peri-enteric findings. Radiologic definitions of strictures have been developed for CTE and MRE; their reliability and responsiveness are being evaluated in index development programs. A comprehensive assessment strategy for strictures using IUS is needed. AIMS: To provide a detailed summary of definitions, diagnosis and monitoring of strictures on IUS as well as technical aspects of image acquisition. METHODS: We searched four databases up to 6 January 2024. Two-stage screening was done in duplicate. We assessed risk of bias using QUADAS-2. RESULTS: There were 56 studies eligible for inclusion. Definitions for strictures on IUS are heterogeneous, but the overall accuracy for diagnosis of strictures is high. The capability of IUS for characterising inflammation versus fibrosis in strictures is not accurate enough to be used in clinical practice or trials. We summarise definitions for improvement of strictures on IUS, and discuss parameters for image acquisition and standardisation. CONCLUSIONS: This systematic review is the first step for a structured program to develop a stricture IUS index for CD.

Magnetic resonance enterography and intestinal ultrasound for the assessment and monitoring of Crohn's disease.

Magnetic resonance enterography (MRE) and intestinal ultrasound (IUS) have developed rapidly in the last few decades, emerging as the primary non-invasive options for both diagnosing and monitoring Crohn's disease (CD). In this review, we evaluate the pertinent data relating to the use of MRE and IUS in CD. We summarise the key imaging features of CD activity, highlight their increasing role in both the clinical and research settings, and discuss how these modalities fit within the diagnostic pathway. We discuss how they can be used to assess disease activity and treatment responsiveness, including the emergence of activity scores for standardised reporting. Additionally, we address areas of controversy such as the use of contrast agents, the role of diffusion-weighted imaging, and discuss point-of-care ultrasound. We also highlight exciting new developments including the applications of artificial intelligence. Finally, we provide suggestions for future research priorities.

Paris classification of colonic polyps using CT colonography: prospective cohort study of interobserver variation.

BACKGROUND: The Paris classification categorises colorectal polyp morphology. Interobserver agreement for Paris classification has been assessed at optical colonoscopy (OC) but not CT colonography (CTC). We aimed to determine the following: (1) interobserver agreement for the Paris classification using CTC between radiologists; (2) if radiologist experience influenced classification, gross polyp morphology, or polyp size; and (3) the extent to which radiologist classifications agreed with (a) colonoscopy and (b) a combined reference standard. METHODS: Following ethical approval for this non-randomised prospective cohort study, seven radiologists from three hospitals classified 52 colonic polyps using the Paris system. We calculated interobserver agreement using Fleiss kappa and mean pairwise agreement (MPA). Absolute agreement was calculated between radiologists; between CTC and OC; and between CTC and a combined reference standard using all available imaging, colonoscopic, and histopathological data. RESULTS: Overall interobserver agreement between the seven readers was fair (Fleiss kappa 0.33; 95% CI 0.30-0.37; MPA 49.7%). Readers with < 1500 CTC experience had higher interobserver agreement (0.42 (95% CI 0.35-0.48) vs. 0.33 (95% CI 0.25-0.42)) and MPA (69.2% vs 50.6%) than readers with ≥ 1500 experience. There was substantial overall agreement for flat vs protuberant polyps (0.62 (95% CI 0.56-0.68)) with a MPA of 87.9%. Agreement between CTC and OC classifications was only 44%, and CTC agreement with the combined reference standard was 56%. CONCLUSION: Radiologist agreement when using the Paris classification at CT colonography is low, and radiologist classification agrees poorly with colonoscopy. Using the full Paris classification in routine CTC reporting is of questionable value. CLINICAL RELEVANCE STATEMENT: Interobserver agreement for radiologists using the Paris classification to categorise colorectal polyp morphology is only fair; routine use of the full Paris classification at CT colonography is questionable. KEY POINTS: • Overall interobserver agreement for the Paris classification at CT colonography (CTC) was only fair, and lower than for colonoscopy. • Agreement was higher for radiologists with < 1500 CTC experience and for larger polyps. There was substantial agreement when classifying polyps as protuberant vs flat. • Agreement between CTC and colonoscopic polyp classification was low (44%).

Causal Mediation of Neighborhood-Level Pediatric Hospitalization Inequities.

BACKGROUND AND OBJECTIVES: Population-wide racial inequities in child health outcomes are well documented. Less is known about causal pathways linking inequities and social, economic, and environmental exposures. Here, we sought to estimate the total inequities in population-level hospitalization rates and determine how much is mediated by place-based exposures and community characteristics. METHODS: We employed a population-wide, neighborhood-level study that included youth <18 years hospitalized between July 1, 2016 and June 30, 2022. We defined a causal directed acyclic graph a priori to estimate the mediating pathways by which marginalized population composition causes census tract-level hospitalization rates. We used negative binomial regression models to estimate hospitalization rate inequities and how much of these inequities were mediated indirectly through place-based social, economic, and environmental exposures. RESULTS: We analyzed 50 719 hospitalizations experienced by 28 390 patients. We calculated census tract-level hospitalization rates per 1000 children, which ranged from 10.9 to 143.0 (median 45.1; interquartile range 34.5 to 60.1) across included tracts. For every 10% increase in the marginalized population, the tract-level hospitalization rate increased by 6.2% (95% confidence interval: 4.5 to 8.0). After adjustment for tract-level community material deprivation, crime risk, English usage, housing tenure, family composition, hospital access, greenspace, traffic-related air pollution, and housing conditions, no inequity remained (0.2%, 95% confidence interval: -2.2 to 2.7). Results differed when considering subsets of asthma, type 1 diabetes, sickle cell anemia, and psychiatric disorders. CONCLUSIONS: Our findings provide additional evidence supporting structural racism as a significant root cause of inequities in child health outcomes, including outcomes at the population level.

Diagnostic performance of sonographic activity scores for adult terminal ileal Crohn's disease compared to magnetic resonance and histological reference standards: experience from the METRIC trial.

OBJECTIVES: The simple ultrasound activity score for Crohn's disease (SUS-CD) and bowel ultrasound score (BUSS) are promising intestinal ultrasound (IUS) indices of CD, but studied mainly in small settings with few sonographers. We compared SUS-CD and BUSS against histological and magnetic resonance enterography (MRE) reference standards in a post hoc analysis of a prospective multicentre, multireader trial. METHODS: Participants recruited to the METRIC trial (ISRCTN03982913) were studied, including those with available terminal ileal (TI) biopsies. Sensitivity and specificity of SUS-CD and BUSS for TI CD activity were calculated with 95% confidence intervals (CI), from the prospective observations of the original METRIC trial sonographers against the histological activity index (HAI) and the simplified magnetic resonance index of activity (sMARIA). RESULTS: We included 284 patients (median 31.5 years, IQR 23-46) from 8 centres, who underwent IUS and MRE. Of these, 111 patients had available terminal ileal biopsies with HAI scoring. Against histology, sensitivity and specificity for active disease were 79% (95% CI 69-86%) and 50% (31-69%) for SUS-CD, and 66% (56-75%) and 68% (47-84%) for BUSS, respectively. Compared to sMARIA, the sensitivity and specificity for active CD were 81% (74-86%) and 75% (66-83%) for SUS-CD, and 68% (61-74%) and 85% (76-91%) for BUSS, respectively. The sensitivity of SUS-CD was significantly greater than that of BUSS against HAI and sMARIA (p < 0.001), but its specificity was significantly lower than of BUSS against the MRE reference standard (p = 0.003). CONCLUSIONS: Particularly when compared to MRE activity scoring, SUS-CD and BUSS are promising tools in a real-world clinical setting. CLINICAL RELEVANCE STATEMENT: When tested using data from a multicentre, multireader diagnostic accuracy trial, the simple ultrasound activity score for Crohn's disease (SUS-CD) and bowel ultrasound score (BUSS) were clinically viable intestinal ultrasound indices that were reasonably sensitive and specific for terminal ileal Crohn's disease, especially when compared to a magnetic resonance reference standard. KEY POINTS: The simple ultrasound activity score for Crohn's disease and bowel ultrasound score are promising intestinal ultrasound indices of Crohn's disease but to date studied mainly in small settings with few sonographers. Compared to histology and the magnetic resonance reference standard in a multicentre, multireader setting, the sensitivity of simple ultrasound activity score for Crohn's disease is significantly greater than that of bowel ultrasound score. The specificity of simple ultrasound activity score for Crohn's disease was significantly lower than that of bowel ultrasound score compared to the magnetic resonance enterography reference standard. The specificity of both indices was numerically higher when the magnetic resonance enterography reference standard was adopted.

Recommendations for Standardizing MRI-based Evaluation of Perianal Fistulizing Disease Activity in Pediatric Crohn's Disease Clinical Trials.

BACKGROUND: Perianal fistulas and abscesses occur commonly as complications of pediatric Crohn's disease (CD). A validated imaging assessment tool for quantification of perianal disease severity and activity is needed to evaluate treatment response. We aimed to identify magnetic resonance imaging (MRI)-based measures of perianal fistulizing disease activity and study design features appropriate for pediatric patients. METHODS: Seventy-nine statements relevant to MRI-based assessment of pediatric perianal fistulizing CD activity and clinical trial design were generated from literature review and expert opinion. Statement appropriateness was rated by a panel (N = 15) of gastroenterologists, radiologists, and surgeons using modified RAND/University of California Los Angeles appropriateness methodology. RESULTS: The modified Van Assche Index (mVAI) and the Magnetic Resonance Novel Index for Fistula Imaging in CD (MAGNIFI-CD) were considered appropriate instruments for use in pediatric perianal fistulizing disease clinical trials. Although there was concern regarding the use of intravascular contrast material in pediatric patients, its use in clinical trials was considered appropriate. A clinically evident fistula tract and radiologic disease defined as at least 1 fistula or abscess on pelvic MRI were considered appropriate trial inclusion criteria. A coprimary clinical and radiologic end point and inclusion of a patient-reported outcome were also considered appropriate. CONCLUSION: Outcomes of treatment of perianal fistulizing disease in children must include MRI. Existing multi-item measures, specifically the mVAI and MAGNIFI-CD, can be adapted and used for children. Further research to assess the operating properties of the indices when used in a pediatric patient population is ongoing.

Outcomes and potential impact of a virtual hands-on training program on MRI staging confidence and performance in rectal cancer.

OBJECTIVES: To explore the potential impact of a dedicated virtual training course on MRI staging confidence and performance in rectal cancer. METHODS: Forty-two radiologists completed a stepwise virtual training course on rectal cancer MRI staging composed of a pre-course (baseline) test with 7 test cases (5 staging, 2 restaging), a 1-day online workshop, 1 month of individual case readings (n = 70 cases with online feedback), a live online feedback session supervised by two expert faculty members, and a post-course test. The ESGAR structured reporting templates for (re)staging were used throughout the course. Results of the pre-course and post-course test were compared in terms of group interobserver agreement (Krippendorf's alpha), staging confidence (perceived staging difficulty), and diagnostic accuracy (using an expert reference standard). RESULTS: Though results were largely not statistically significant, the majority of staging variables showed a mild increase in diagnostic accuracy after the course, ranging between + 2% and + 17%. A similar trend was observed for IOA which improved for nearly all variables when comparing the pre- and post-course. There was a significant decrease in the perceived difficulty level (p = 0.03), indicating an improved diagnostic confidence after completion of the course. CONCLUSIONS: Though exploratory in nature, our study results suggest that use of a dedicated virtual training course and web platform has potential to enhance staging performance, confidence, and interobserver agreement to assess rectal cancer on MRI virtual training and could thus be a good alternative (or addition) to in-person training. CLINICAL RELEVANCE STATEMENT: Rectal cancer MRI reporting quality is highly dependent on radiologists' expertise, stressing the need for dedicated training/teaching. This study shows promising results for a virtual web-based training program, which could be a good alternative (or addition) to in-person training. KEY POINTS: • Rectal cancer MRI reporting quality is highly dependent on radiologists' expertise, stressing the need for dedicated training and teaching. • Using a dedicated virtual training course and web-based platform, encouraging first results were achieved to improve staging accuracy, diagnostic confidence, and interobserver agreement. • These exploratory results suggest that virtual training could thus be a good alternative (or addition) to in-person training.

Weight-loss Independent Clinical and Metabolic Biomarkers Associated with Type 2 Diabetes Remission Post-bariatric/metabolic Surgery.

PURPOSE: Remission of type 2 diabetes (T2D) can be achieved by many, but not all, people following bariatric/metabolic surgery. The mechanisms underlying T2D remission remain incompletely understood. This observational study aimed to identify novel weight-loss independent clinical, metabolic and genetic factors that associate with T2D remission using comprehensive phenotyping. MATERIALS AND METHODS: Ten patients without T2D remission (non-remitters) were matched to 10 patients with T2D remission (remitters) for age, sex, type of surgery, body weight, BMI, post-operative weight loss, duration from surgery and duration of T2D. Detailed body composition assessed using magnetic resonance imaging, gut hormones, serum metabolomics, insulin sensitivity, and genetic risk scores for T2D and anthropometric traits were assessed. RESULTS: Remitters had significantly greater ß-cell function and circulating acyl ghrelin levels, but lower visceral adipose tissue (VAT): subcutaneous adipose tissue (SAT) ratio than non-remitters. Branched-chain amino acids (BCAAs) and VLDL particle size were the most discriminant metabolites between groups. A significant positive correlation between, VAT area, VAT:SAT ratio and circulating levels of BCAAs was observed, whereas a significant negative correlation between BCAAs and ß-cell function was revealed. CONCLUSION: We highlight a potentially novel relationship between VAT and BCAAs, which may play a role in glucoregulatory control. Improvement in ß-cell function, and the role ghrelin plays in its recovery, is likely another key factor influencing T2D remission post-surgery. These findings suggest that adjunctive approaches that target VAT loss and restoration of BCAA metabolism might achieve higher rates of long-term T2D remission post-surgery.

Small bowel imaging in inflammatory bowel disease: updates for 2023.

INTRODUCTION: Cross-sectional imaging techniques including MR and CT enterography and ultrasound are integral to Crohn's disease management, accurate, responsive, and well tolerated. They assess the full thickness of the bowel wall, perienteric environment, and distant complications. As we strive toward tighter disease control, imaging's role will expand further with transmural healing becoming an increasingly important therapeutic target. AREAS COVERED: MEDLINE and Web of Science were searched from 2012 to 2023 inclusive. We review the evidence for cross-sectional imaging in assessing disease activity, phenotyping, and therapeutic response assessment. Emerging novel imaging applications such as quantifying enteric motility and fibrosis, prognostication, and potential utility of artificial intelligence will be covered. Recent international consensus statements highlight the need for standardized imaging reporting and definitions of transmural healing and remission. We will discuss how recent advances may be best integrated into patient care and highlight key outstanding research questions. EXPERT OPINION: Cross-sectional imaging is established in Crohn's disease management. Research emphasis should be placed on optimal integration of imaging modalities in clinical care pathways, workforce training, definitions, and evidence for use of imaging based therapeutic targets such as transmural healing, better phenotyping of stricturing disease, and developing novel techniques, including integration of artificial intelligence.

Habit training versus habit training with direct visual biofeedback in adults with chronic constipation: A randomized controlled trial.

AIM: The aim was to determine whether specialist-led habit training using Habit Training with Biofeedback (HTBF) is more effective than specialist-led habit training alone (HT) for chronic constipation and whether outcomes of interventions are improved by stratification to HTBF or HT based on diagnosis (functional defaecation disorder vs. no functional defaecation disorder) by radio-physiological investigations (INVEST). METHOD: This was a parallel three-arm randomized single-blinded controlled trial, permitting two randomized comparisons: HTBF versus HT alone; INVEST- versus no-INVEST-guided intervention. The inclusion criteria were age 18-70 years; attending specialist hospitals in England; self-reported constipation for >6 months; refractory to basic treatment. The main exclusions were secondary constipation and previous experience of the trial interventions. The primary outcome was the mean change in Patient Assessment of Constipation Quality of Life score at 6 months on intention to treat. The secondary outcomes were validated disease-specific and psychological questionnaires and cost-effectiveness (based on EQ-5D-5L). RESULTS: In all, 182 patients were randomized 3:3:2 (target 384): HT n = 68; HTBF n = 68; INVEST-guided treatment n = 46. All interventions had similar reductions (improvement) in the primary outcome at 6 months (approximately -0.8 points of a 4-point scale) with no statistically significant difference between HT and HTBF (-0.03 points; 95% CI -0.33 to 0.27; P = 0.85) or INVEST versus no-INVEST (0.22; -0.11 to 0.55; P = 0.19). Secondary outcomes showed a benefit for all interventions with no evidence of greater cost-effectiveness of HTBF or INVEST compared with HT. CONCLUSION: The results of the study at 6 months were inconclusive. However, with the caveat of under-recruitment and further attrition at 6 months, a simple, cheaper approach to intervention may be as clinically effective and more cost-effective than more complex and invasive approaches.