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%).

CT Colonography Reporting and Data System (C-RADS): Version 2023 Update.

The CT Colonography Reporting and Data System (C-RADS) has withstood the test of time and proven to be a robust classification scheme for CT colonography (CTC) findings. C-RADS version 2023 represents an update on the scheme used for colorectal and extracolonic findings at CTC. The update provides useful insights gained since the implementation of the original system in 2005. Increased experience has demonstrated confusion on how to classify the mass-like appearance of the colon consisting of soft tissue attenuation that occurs in segments with acute or chronic diverticulitis. Therefore, the update introduces a new subcategory, C2b, specifically for mass-like diverticular strictures, which are likely benign. Additionally, the update simplifies extracolonic classification by combining E1 and E2 categories into an updated extracolonic category of E1/E2 since, irrespective of whether a finding is considered a normal variant (category E1) or an otherwise clinically unimportant finding (category E2), no additional follow-up is required. This simplifies and streamlines the classification into one category, which results in the same management recommendation.

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.

Development and Evaluation of Machine Learning in Whole-Body Magnetic Resonance Imaging for Detecting Metastases in Patients With Lung or Colon Cancer: A Diagnostic Test Accuracy Study.

OBJECTIVES: Whole-body magnetic resonance imaging (WB-MRI) has been demonstrated to be efficient and cost-effective for cancer staging. The study aim was to develop a machine learning (ML) algorithm to improve radiologists' sensitivity and specificity for metastasis detection and reduce reading times. MATERIALS AND METHODS: A retrospective analysis of 438 prospectively collected WB-MRI scans from multicenter Streamline studies (February 2013-September 2016) was undertaken. Disease sites were manually labeled using Streamline reference standard. Whole-body MRI scans were randomly allocated to training and testing sets. A model for malignant lesion detection was developed based on convolutional neural networks and a 2-stage training strategy. The final algorithm generated lesion probability heat maps. Using a concurrent reader paradigm, 25 radiologists (18 experienced, 7 inexperienced in WB-/MRI) were randomly allocated WB-MRI scans with or without ML support to detect malignant lesions over 2 or 3 reading rounds. Reads were undertaken in the setting of a diagnostic radiology reading room between November 2019 and March 2020. Reading times were recorded by a scribe. Prespecified analysis included sensitivity, specificity, interobserver agreement, and reading time of radiology readers to detect metastases with or without ML support. Reader performance for detection of the primary tumor was also evaluated. RESULTS: Four hundred thirty-three evaluable WB-MRI scans were allocated to algorithm training (245) or radiology testing (50 patients with metastases, from primary 117 colon [n = 117] or lung [n = 71] cancer). Among a total 562 reads by experienced radiologists over 2 reading rounds, per-patient specificity was 86.2% (ML) and 87.7% (non-ML) (-1.5% difference; 95% confidence interval [CI], -6.4%, 3.5%; P = 0.39). Sensitivity was 66.0% (ML) and 70.0% (non-ML) (-4.0% difference; 95% CI, -13.5%, 5.5%; P = 0.344). Among 161 reads by inexperienced readers, per-patient specificity in both groups was 76.3% (0% difference; 95% CI, -15.0%, 15.0%; P = 0.613), with sensitivity of 73.3% (ML) and 60.0% (non-ML) (13.3% difference; 95% CI, -7.9%, 34.5%; P = 0.313). Per-site specificity was high (>90%) for all metastatic sites and experience levels. There was high sensitivity for the detection of primary tumors (lung cancer detection rate of 98.6% with and without ML [0.0% difference; 95% CI, -2.0%, 2.0%; P = 1.00], colon cancer detection rate of 89.0% with and 90.6% without ML [-1.7% difference; 95% CI, -5.6%, 2.2%; P = 0.65]). When combining all reads from rounds 1 and 2, reading times fell by 6.2% (95% CI, -22.8%, 10.0%) when using ML. Round 2 read-times fell by 32% (95% CI, 20.8%, 42.8%) compared with round 1. Within round 2, there was a significant decrease in read-time when using ML support, estimated as 286 seconds (or 11%) quicker ( P = 0.0281), using regression analysis to account for reader experience, read round, and tumor type. Interobserver variance suggests moderate agreement, Cohen κ = 0.64; 95% CI, 0.47, 0.81 (with ML), and Cohen κ = 0.66; 95% CI, 0.47, 0.81 (without ML). CONCLUSIONS: There was no evidence of a significant difference in per-patient sensitivity and specificity for detecting metastases or the primary tumor using concurrent ML compared with standard WB-MRI. Radiology read-times with or without ML support fell for round 2 reads compared with round 1, suggesting that readers familiarized themselves with the study reading method. During the second reading round, there was a significant reduction in reading time when using ML support.

How to effectively use and interpret the barium swallow: Current role in esophageal dysphagia.

BACKGROUND: The barium swallow is a commonly performed investigation, though recent decades have seen major advances in other esophageal diagnostic modalities. PURPOSE: The purpose of this review is to clarify the rationale for components of the barium swallow protocol, provide guidance on interpretation of findings, and describe the current role of the barium swallow in the diagnostic paradigm for esophageal dysphagia in relation to other esophageal investigations. The barium swallow protocol, interpretation, and reporting terminology are subjective and non-standardized. Common reporting terminology and an approach to their interpretation are provided. A timed barium swallow (TBS) protocol provides more standardized assessment of esophageal emptying but does not evaluate peristalsis. Barium swallow may have higher sensitivity than endoscopy for detecting subtle strictures. Barium swallow has lower overall accuracy than high-resolution manometry for diagnosing achalasia but can help secure the diagnosis in cases of equivocal manometry. TBS has an established role in objective assessment of therapeutic response in achalasia and helps identify the cause of symptom relapse. Barium swallow has a role in the evaluating manometric esophagogastric junction outflow obstruction, in some cases helping to identify where it represents an achalasia-like syndrome. Barium swallow should be performed in dysphagia following bariatric or anti-reflux surgery, to assess for both structural and functional postsurgical abnormality. Barium swallow remains a useful investigation in esophageal dysphagia, though its role has evolved due to advancements in other diagnostics. Current evidence-based guidance regarding its strengths, weaknesses, and current role are described in this review.

Training in Computed Tomographic Colonography Interpretation: Recommendations for Best Practice.

The value of computed tomographic colonography (CTC) as a sensitive diagnostic investigation for colorectal cancer is well established. However, there is lack of consensus in the best way to achieve expertise in interpreting these studies. In this review we discuss the value of CTC training, accreditation and performance monitoring; the qualities of good CTC interpretation training, and specific training cases with associated learning points.

Effectiveness of Training in CT Colonography Interpretation: Review of Current Literature.

International guidance recommends that readers be specifically trained before embarking on independent interpretation of CT colonography (CTC) examinations. Systematic comparison of both international training requirements and the effectiveness of CTC training is lacking in the published literature. Therefore, we identified available international training standards for CTC and performed a review of studies published in the last 20 years to assess the impact of CTC interpretation training on reader diagnostic accuracy. A wide variation in training requirements was observed. Studies of the effectiveness of CTC reader training were heterogenous in methodology, with large variation in sample size and the type of training administered. Although training in CTC interpretation improves reader sensitivity overall, it has varying impact on specificity. Consensus agreement on the best way to train and assess readers in CTC interpretation may lead to lasting improvements in reader performance.

METRIC-EF: magnetic resonance enterography to predict disabling disease in newly diagnosed Crohn's disease-protocol for a multicentre, non-randomised, single-arm, prospective study.

INTRODUCTION: Crohn's disease (CD) is characterised by discontinuous, relapsing enteric inflammation. Instituting advanced therapies at an early stage to suppress inflammation aims to prevent future complications such as stricturing or penetrating disease, and subsequent surgical resection. Therapeutics are effective but associated with certain side-effects and relatively expensive. There is therefore an urgent need for robust methods to predict which newly diagnosed patients will develop disabling disease, to identify patients who are most likely to benefit from early, advanced therapies. We aim to determine if magnetic resonance enterography (MRE) features at diagnosis improve prediction of disabling CD within 5 years of diagnosis. METHODS AND ANALYSIS: We describe the protocol for a multicentre, non-randomised, single-arm, prospective study of adult patients with newly diagnosed CD. We will use patients already recruited to the METRIC study and extend their clinical follow-up, as well as a separate group of newly diagnosed patients who were not part of the METRIC trial (MRE within 3 months of diagnosis), to ensure an adequate sample size. Follow-up will extend for at least 4 years. The primary outcome is to evaluate the comparative predictive ability of prognostic models incorporating MRE severity scores (Magnetic resonance Enterography Global Score (MEGS), simplified MAgnetic Resonance Index of Activity (sMaRIA) and Lémann Index) versus models using standard characteristics alone to predict disabling CD (modified Beaugerie definition) within 5 years of new diagnosis. ETHICS AND DISSEMINATION: This study protocol achieved National Health Service Research Ethics Committee (NHS REC), London-Hampstead Research Ethics Committee approval (IRAS 217422). Our findings will be disseminated via conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: ISRCTN76899103.

The development of a minimum dataset for MRI reporting of anorectal fistula: a multi-disciplinary, expert consensus process.

There are a range of sphincter-preserving procedures available to treat anorectal fistula, some of which can be precluded, or rendered more optimal by specific features of fistula anatomy. Magnetic resonance imaging (MRI) is the gold standard modality for assessing anorectal fistula. To maximise clinical utility, the MRI report should accurately describe these clinically relevant features. We aimed to develop a minimum dataset for reporting MRI of anorectal fistula, in order to improve the assessment and management of these patients. A longlist of 70 potential items for the minimum dataset was generated through systematic review of the literature. This longlist was presented to radiologists, surgeons and gastroenterologists in an online survey to understand the features that shape current clinical practice. The longlist and survey results were then presented to an expert consensus panel to generate the final minimum dataset through discussion and anonymous voting. The final minimum dataset details the general characteristics, features of the internal and external openings, path of the fistula through the sphincters and any associated extensions and collections that should be described in all MRI reports for anal fistula. Additional surgical and perianal Crohn's disease subsets were developed to indicate the features that aid decision-making for these patients, in addition to a minimum dataset for the clinical request. This study represents a multi-disciplinary approach to developing a minimum dataset for MRI reporting of anal fistula, highlighting the most important features to report that can assist in clinical decision-making. KEY POINTS: • This paper recommends the minimum features that should be included in all MRI reports for the assessment of anal fistula, including Parks classification, number of tracts, features of the internal and external opening, path of the tract through the sphincters, the presence and features of extensions and collections. • Additional features that aid decision-making for surgery or in the presence of Crohn's disease have been identified. • The items that should be included when requesting an MRI are specified.

Systematic review and meta-analysis of prophylaxis use with intravenous contrast exposure to prevent contrast-induced nephropathy.

PURPOSE: Iodinated radiographic contrast media has been associated with an acute deterioration in renal function, termed contrast induced nephropathy (CIN). This review aims to establish the efficacy of prophylaxis interventions used in adult patients prior to intravenous exposure to iodinated contrast to reduce the risk of CIN. METHODS: An electronic search for published peer-reviewed articles was performed, supplemented with manual review of references from previous systematic reviews and the National Institute for Health and Care Excellence guidelines. Risk of bias was assessed using the Cochrane Collaboration's tool for assessing risk of bias. Random-effect meta-analyses were used to assess CIN incidence, need for kidney replacement therapy (KRT), mortality, fluid overload and persistent kidney dysfunction. RESULTS: 22 studies assessing a range of interventions were included in the qualitative analysis. The incidence of CIN was reduced by the use of N-acetylcysteine compared to a control group of saline (risk difference = -0.07, 95% CI -0.13 to -0.01) but not by sodium bicarbonate compared to control group of saline (risk difference = -0.02, 95% CI -0.04 to 0.01). Published studies give no indication that prophylactic interventions have significant impact on the need for KRT, mortality or persistent renal impairment. CONCLUSION: Evidence for prophylaxis against CIN in patients receiving intravenous iodinated contrast is limited. There was an association with the use of NAC with reduced incidence of CIN following intravenous contrast but there was no impact on other clinical outcomes assessed. The clinical significance of these findings remains unclear and further research focusing on these clinical outcomes is required.

Diagnostic Performance of Magnetic Resonance Enterography Disease Activity Indices Compared with a Histological Reference Standard for Adult Terminal Ileal Crohn's Disease: Experience from the METRIC Trial.

BACKGROUND AND AIMS: The simplified magnetic resonance enterography [MRE] index of activity [sMARIA], London, and 'extended' London, scoring systems are widely used in Crohn's disease [CD] to assess disease activity, although validation studies have usually been single-centre, retrospective, and/or used few readers. Here, we evaluated these MRE indices within a prospective, multicentre, multireader, diagnostic accuracy trial. METHODS: A subset of participants [newly diagnosed or suspected of relapse] recruited to the METRIC trial with available terminal ileal [TI] biopsies was included. Using pre-specified thresholds, the sensitivity and specificity of sMARIA, London, and 'extended' London scores for active and severe [sMARIA] TI CD were calculated using different thresholds for the histological activity index [HAI]. RESULTS: We studied 111 patients [median age 29 years, interquartile range 21-41, 75 newly diagnosed, 36 suspected relapse] from seven centres, of whom 22 had no active TI CD [HAI = 0], 39 mild [HAI = 1], 13 moderate [HAI = 2], and 37 severe CD activity [HAI = 3]. In total, 26 radiologists prospectively scored MRE datasets as per their usual clinical practice. Sensitivity and specificity for active disease [HAI >0] were 83% [95% confidence interval 74% to 90%] and 41% [23% to 61%] for sMARIA, 76% [67% to 84%] and 64% [43% to 80%] for the London score, and 81% [72% to 88%] and 41% [23% to 61%] for the 'extended' London score, respectively. The sMARIA had 84% [69-92%] sensitivity and 53% [41-64%] specificity for severe CD. CONCLUSIONS: When tested at their proposed cut-offs in a real-world setting, sMARIA, London, and 'extended' London indices achieve high sensitivity for active TI disease against a histological reference standard, but specificity is low.

Are preoperative CT variables associated with the success or failure of subsequent ventral hernia repair: nested case-control study.

OBJECTIVES: Systematic review of CT measurements to predict the success or failure of subsequent ventral hernia repair has found limited data available in the indexed literature. To rectify this, we investigated multiple preoperative CT metrics to identify if any were associated with postoperative reherniation. METHODS: Following ethical permission, we identified patients who had undergone ventral hernia repair and had preoperative CT scanning available. Two radiologists made multiple measurements of the hernia and abdominal musculature from these scans, including loss of domain. Patients were divided subsequently into two groups, defined by hernia recurrence at 1-year subsequent to surgery. Hypothesis testing investigated any differences between CT measurements from each group. RESULTS: One hundred eighty-eight patients (95 male) were identified, 34 (18%) whose hernia had recurred by 1-year. Only three of 34 CT measurements were significantly different when patients whose hernia had recurred were compared to those who had not; these significant findings were assumed contingent on multiple testing. In particular, preoperative hernia volume (recurrence 155.3 cc [IQR 355.65] vs. no recurrence 78.2 [IQR 303.52], p = 0.26) nor loss of domain, whether calculated using the Tanaka (recurrence 0.02 [0.04] vs. no recurrence 0.009 [0.04], p = 0.33) or Sabbagh (recurrence 0.019 [0.05] vs. no recurrence 0.009 [0.04], p = 0.25) methods, differed between significantly between groups. CONCLUSIONS: Preoperative CT measurements of ventral hernia morphology, including loss of domain, appear unrelated to postoperative recurrence. It is likely that the importance of such measurements to predict recurrence is outweighed by other patient factors and surgical reconstruction technique. KEY POINTS: • Preoperative CT scanning is often performed for ventral hernia but systematic review revealed little data regarding whether CT variables predict postoperative reherniation. • We found that the large majority of CT measurements, including loss of domain, did not differ significantly between patients whose hernia did and did not recur. • It is likely that the importance of CT measurements to predict recurrence is outweighed by other patient factors and surgical reconstruction technique.

Contemporary imaging of inguinal hernia and pain.

Inguinal hernias are the commonest type of hernia, and are frequently encountered by general, abdominal and musculoskeletal radiologists. Such hernias may cause discomfort or pain; but many other conditions may cause pain in a similar location, meaning it is not always straightforward to determine the underlying cause of a particular patient's symptoms. Although surgical fixation of hernia has high success rates with low recurrence, ongoing symptoms are common after apparently uncomplicated surgery. In particular, post-surgical chronic groin pain can be highly problematic in some patients. In this review, we highlight the relevant surgical and imaging anatomy, common modes of clinical presentation, contemporary surgical approaches to the repair of inguinal hernia, imaging techniques to diagnose such hernias in both unoperated and operated groins and mimics of hernia-related pain.

Interobserver variation in the interpretation of magnetic resonance enterography in Crohn's disease.

OBJECTIVES: To evaluate interobserver variability for diagnosis of disease presence and extent of small bowel and colonic Crohn's disease using MR enterography (MRE). METHODS: Data from the first 73 consecutive patients (mean age 32, 33F, 28 new diagnosis, 45 suspected relapse) recruited to a multicentre, prospective diagnostic accuracy trial evaluating MRE for small bowel Crohn's disease were each read independently by three (from a pool of 20) radiologists. Radiologists documented presence and segmental location of small bowel Crohn's disease and recorded morphological mural/extramural parameters for involved segments. Per patient percentage agreement for disease presence and extent were calculated against an outcome-based construct reference standard (averaged between pairs of readers). Prevalence-adjusted bias-adjusted κ (PABAK) was calculated. RESULTS: Agreement for small bowel disease presence for new diagnosis/relapsed patients was 68%(κ = 0.36)/ 78% (κ = 0.56) and 43%(κ = 0.14)/ 53% for disease extent (κ = 0.07), respectively. For disease presence, all three radiologists agreed correctly with the reference standard in 41/59 (69%) of patients with small bowel involvement, and in 8/14 (57%) cases of without small bowel disease. Agreement was highest for multisegment disease, greater than 5 cm in length, with mural thickness>6 mm, and increased mural T2 signal. Agreement for colonic disease presence was 61% (κ = 0.21 fair agreement) for new diagnosis/ 60% (κ = 0.20, slight agreement) for relapsed patients. CONCLUSION: There is a reasonable agreement between radiologists for small bowel disease presence using MRE for newly diagnosed Crohn's disease, and patients with suspected relapse, respectively. Agreement is lower for disease extent. ADVANCES IN KNOWLEDGE: There is reasonable agreement between radiologists for small bowel disease presence using MRE for newly diagnosed (68%) Crohn's disease, and patients with suspected relapse (78%). Agreement is lower for disease extent (43% new diagnosis and 53% suspected relapse).

Colorectal Cancer: Performance and Evaluation for CT Colonography Screening- A Multicenter Cluster-randomized Controlled Trial.

Background Most radiologists reporting CT colonography (CTC) do not undergo compulsory performance accreditation, potentially lowering diagnostic sensitivity. Purpose To determine whether 1-day individualized training in CTC reporting improves diagnostic sensitivity of experienced radiologists for 6-mm or larger lesions, the durability of any improvement, and any associated factors. Materials and Methods This prospective, multicenter cluster-randomized controlled trial was performed in National Health Service hospitals in England and Wales between April 2017 and January 2020. CTC services were cluster randomized into intervention (1-day training plus feedback) or control (no training or feedback) arms. Radiologists in the intervention arm attended a 1-day workshop focusing on CTC reporting pitfalls with individualized feedback. Radiologists in the control group received no training. Sensitivity for 6-mm or larger lesions was tested at baseline and 1, 6, and 12 months thereafter via interpretation of 10 CTC scans at each time point. The primary outcome was the mean difference in per-lesion sensitivity between arms at 1 month, analyzed using multilevel regression after adjustment for baseline sensitivity. Secondary outcomes included per-lesion sensitivity at 6- and 12-month follow-up, sensitivity for flat neoplasia, and effect of prior CTC experience. Results A total of 69 hospitals were randomly assigned to the intervention (31 clusters, 80 radiologists) or control (38 clusters, 59 radiologists) arm. Radiologists were experienced (median, 500-999 CTC scans interpreted) and reported CTC scans routinely (median, 151-200 scans per year). One-month sensitivity improved after intervention (66.4% [659 of 992]) compared with sensitivity in the control group (42.4% [278 of 655]; difference = 20.8%; 95% CI: 14.6, 27.0; P < .001). Improvements were maintained at 6 (66.4% [572 of 861] vs 50.5% [283 of 560]; difference = 13.0%; 95% CI: 7.4, 18.5; P < .001) and 12 (63.7% [310 of 487] vs 44.4% [187 of 421]; difference = 16.7%; 95% CI: 10.3, 23.1; P < .001) months. This beneficial effect applied to flat lesions (difference = 22.7%; 95% CI: 15.5, 29.9; P < .001) and was independent of career experience (≥1500 CTC scans: odds ratio = 1.09; 95% CI: 0.88, 1.36; P = .22). Conclusion For radiologists evaluating CT colonography studies, a 1-day training intervention yielded sustained improvement in detection of clinically relevant colorectal neoplasia, independent of previous career experience. Clinical trial registration no. NCT02892721 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Pickhardt in this issue. An earlier incorrect version appeared online and in print. This article was corrected on February 28, 2022.

Solitary rectal ulcer syndrome (SRUS): observational case series findings on MR defecography.

OBJECTIVE: Radiological findings in solitary rectal ulcer syndrome (SRUS) are well described for evacuation proctography (EP) but sparse for magnetic resonance defecography (MRD). In order to rectify this, we describe the spectrum of MRD findings in patients with histologically proven SRUS. MATERIALS AND METHODS: MRD from twenty-eight patients (18 female; 10 males) with histologically confirmed SRUS were identified. MRD employed a 1.5-T magnet and a standardized technique with the rectal lumen filled with gel and imaged sagittally in the supine position, before, during, and after attempted rectal evacuation. A single radiologist observer with 5 years' experience in pelvic floor imaging made the anatomical and functional measurements. RESULTS: Sixteen patients (10 female) demonstrated internal rectal intussusception and 3 patients (11%) demonstrated complete external rectal prolapse. Anterior rectoceles were noted in 12 female patients (43%). Associated anterior and middle compartment weakness (evidenced by excessive descent) was observed in 18 patients (64%). Cystocele was found in 14 patients (50%) and uterine prolapse was noted in 7 patients (25%). Enterocoeles were detected in 5 patients (18%) and peritoneocoele in 5 patients (18%). None had sigmoidocoele. Sixteen patients (57%) demonstrated delayed voiding and 13 patients (46%) incomplete voiding, suggesting defecatory dyssynergia. CONCLUSION: MRD can identify and grade both rectal intussusception and dyssynergia in SRUS, and also depict associated anterior and/or middle compartment descent. Distinction between structural and functional findings has important therapeutic implications. KEY POINTS: MRD can identify and grade both rectal intussusception and dyssynergia in patients with SRUS. MRD is an acceptable substitute to evacuation proctography in assessing anorectal dysfunctions when attempting to avoid ionizing radiation. SRUS influences the pelvic floor globally. MRD depicts associated anterior and/or middle compartment prolapse.

Durable response to serial tyrosine kinase inhibitors (TKIs) in an adolescent with metastatic TFG-ROS1 fusion positive Inflammatory Myofibroblastic Tumor (IMT).

Here, we present the case of an adolescent with a rare metastatic Inflammatory myofibroblastic tumor (IMT) harboring a TFG-ROS1 fusion initially detected on tumor progression and retrospectively identified in the primary tumor after targeted RNA sequencing. The patient benefitted from sequential TKIs over a 5-year period with response to the third generation ALK/ROS inhibitor, lorlatinib leading to resection of the primary tumor. Detailed molecular analysis can identify targetable oncogenic kinase fusions that alters management in patients with unresectable disease and should be considered in all patients.