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%).

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.

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.

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.

Ischaemic colitis: practical challenges and evidence-based recommendations for management.

Ischaemic colitis (IC) is a common condition with rising incidence, and in severe cases a high mortality rate. Its presentation, severity and disease behaviour can vary widely, and there exists significant heterogeneity in treatment strategies and resultant outcomes. In this article we explore practical challenges in the management of IC, and where available make evidence-based recommendations for its management based on a comprehensive review of available literature. An optimal approach to initial management requires early recognition of the diagnosis followed by prompt and appropriate investigation. Ideally, this should involve the input of both gastroenterology and surgery. CT with intravenous contrast is the imaging modality of choice. It can support clinical diagnosis, define the severity and distribution of ischaemia, and has prognostic value. In all but fulminant cases, this should be followed (within 48 hours) by lower gastrointestinal endoscopy to reach the distal-most extent of the disease, providing endoscopic (and histological) confirmation. The mainstay of medical management is conservative/supportive treatment, with bowel rest, fluid resuscitation and antibiotics. Specific laboratory, radiological and endoscopic features are recognised to correlate with more severe disease, higher rates of surgical intervention and ultimately worse outcomes. These factors should be carefully considered when deciding on the need for and timing of surgical intervention.

Adipose tissue imaging as nutritional predictors in patients undergoing enterocutaneous fistula repair.

OBJECTIVES: The management of enterocutaneous fistulae (ECF) is complex, challenging, and often associated with metabolic, septic, and nutritional complications. Radiographic quantification of body composition such as fat or lean body mass distribution is a potentially valuable preoperative assessment tool to optimize nutritional status. The aim of this study was to investigate the correlation between total adipose tissue (fat) area (TFA), assessed by computed tomography and magnetic resonance imaging radiology tests, with body weight, body mass index (BMI), various biochemical parameters, need for nutritional support, and survival in patients undergoing ECF repair. METHODS: Biochemical and anthropometric parameters at the time of ECF surgery were retrospectively collected for adult patients undergoing ECF repair at University College London Hospital, UK. Visceral and subcutaneous adiposity was measured at the level of the third lumbar vertebra (Image J) at computed tomography or magnetic resonance imaging. Statistical analysis included descriptives, univariate and multivariate analysis between TFA and various parameters, and their influence on postoperative survival. RESULTS: A complete set of data was available for 85 patients (51 women, 56.9 ± 14.5 y of age) who underwent ECF repair. ECF originated mainly as a surgical complication (86%) while 14% were undergoing a second ECF repair. Median BMI was 22.8 kg/m2 and mean TFA was 361 ± 174.9 cm2, with a higher visceral fat content in men than in women (183.8 ± 99.2 versus 99 ± 59.7 cm2, P < 0.001). BMI, body weight, and creatinine were significantly positively correlated with TFA (ρ = 0.77, 0.73, and 0.50, respectively, P < 0.001); no correlation was noted between TFA and preoperative albumin levels. Patients in the low TFA group had a higher use of parenteral nutrition (P = 0.049). Hospital length of stay was longer in patients receiving artificial nutrition support (70 versus 22 d, P < 0.001). A TFA cutoff point of 290 cm2 discriminated patients who required artificial nutrition versus no nutritional support with moderate sensitivity (75%) but poor specificity (45%). At multivariate analysis, only >60 y of age (hazard ratio [HR], 2.69, P < 0.02) and use of parenteral nutrition (HR, 3.90, P < 0.02) were associated with worse overall survival. CONCLUSION: Abdominal adiposity was strongly correlated with anthropometric parameters at the time of surgery. Earlier identification of patients requiring artificial nutrition at standard preoperative imaging might allow integration of nutritional optimization into initial clinical management plans reducing length of stay and improving clinical outcomes.

How to avoid describing your radiological research study incorrectly.

This review identifies and examines terms used to describe a radiological research "study" or "trial". A taxonomy of clinical research descriptions is explained with reference to medical imaging examples. Because many descriptive terms have precise methodological implications, it is important that these terms are understood by readers and used correctly by researchers, so that the reader is not misled. KEY POINTS: • Multiple different terms are being used to describe radiological research "studies" and "trials", and many of these terms have precise methodological implications. • Radiological researchers sometimes use titles that describe their research incorrectly. This can mislead the reader as to what was actually done. • It is important that readers and researchers understand the correct taxonomy of clinical research and that researchers adopt the correct description for their work.

The choice and definition of summary measure for meta-analysis of clinical studies with binary outcomes: effect on clinical interpretation.

Many systematic reviews and meta-analyses concern the effect of a healthcare intervention on a binary outcome i.e. occurrence (or not) of a particular event. Usually, the overall effect, pooled across all studies included in the meta-analysis, is summarised using the odds ratio (OR) or the relative risk (RR). Under most circumstances, it is obvious how to identify what should be considered as the event of interest-for example, death or a clinically important side-effect. However, on occasion it may not be clear in which "direction" the event should be specified-such as attendance (vs non-attendance) at cancer screening. Usually, this choice is not critical to the overall conclusion of the meta-analysis, but occasionally it can lead to differences in how the included studies are pooled, ultimately affecting the overall meta-analytic result, particularly when using RRs rather than ORs. In this commentary, we will explain this phenomenon in more detail using examples from the literature, and explore how analysts and readers can avoid some potential pitfalls.

Traditional Serrated Adenomas on CT Colonography: International Multicenter Experience With This Rare Colorectal Neoplasm.

OBJECTIVE. Serrated polyps include hyperplastic polyps, sessile serrated polyps, and traditional serrated adenomas (TSAs). Hyperplastic polyps and sessile serrated polyps account for approximately 99% of all serrated lesions; TSAs are rare. However, both sessile serrated polyps and TSAs are now recognized as precursor lesions to carcinogenesis, representing approximately one-fourth of all sporadic colorectal cancers. We report what is, to our knowledge, the first series describing the characteristics of CTAs on CT colonography (CTC). MATERIALS AND METHODS. An international, multicenter, retrospective review of CT colonography-detected TSAs diagnosed between 2008 and 2018 was conducted. Data collected included patient demographics and data from CTC, optical colonoscopy, and pathologic analysis. RESULTS. A total of 67 proven TSAs in 58 patients (mean age, 67 years) were identified. The majority (66%) were located in the distal colon (descending colon, sigmoid colon, and rectum), and their mean size was 19 mm (range, 3-80 mm). Small (< 10 mm) TSAs typically had a simple sessile or pedunculated morphologic appearance, whereas large (≥ 10 mm) TSAs tended to be more lobulated and irregular, pedunculated, or carpetlike. The majority (88%) showed at least some contrast medium surface coating. CONCLUSION. We report what we believe to be the first multicenter experience describing the characteristics of TSAs on CTC. Unlike sessile serrated lesions, TSAs are more often left-sided and tend to be more lobulated and irregular. However, like sessile serrated polyps, most TSAs show contrast medium surface coating. Detection of these rare lesions on CTC is important, given their malignant potential.

Computed tomographic colonography: how many and how fast should radiologists report?

OBJECTIVES: To determine if polyp detection at computed tomographic colonography (CTC) is associated with (a) the number of CTC examinations interpreted per day and (b) the length of time spent scrutinising the scan. METHODS: Retrospective observational study from two hospitals. We extracted Radiology Information System data for CTC examinations from Jan 2012 to Dec 2015. For each examination, we determined how many prior CTCs had been interpreted by the reporting radiologist on that day and how long radiologists spent on interpretation. For each radiologist, we calculated their referral rate (proportion deemed positive for 6 mm+ polyp/cancer), positive predictive value (PPV) and endoscopic/surgically proven polyp detection rate (PDR). We also calculated the mean time each radiologist spent interpreting normal studies ("negative interpretation time"). We used multilevel logistic regression to investigate the relationship between the number of scans reported each day, negative interpretation time and referral rate, PPV and PDR. RESULTS: Five thousand one hundred ninety-one scans were interpreted by seven radiologists; 892 (17.2%) were reported as positive, and 534 (10.3%) had polyps confirmed. Both referral rate and PDR reduced as more CTCs were reported on a given day (p < 0.001), the odds reducing by 7% for each successive CTC interpreted. Radiologists reporting more slowly than their colleagues detected more polyps (p = 0.028), with each 16% increase in interpretation time associated with a 1% increase in PDR. PPV was unaffected. CONCLUSIONS: Reporting multiple CTCs on a given day and rapid CTC interpretation are associated with decreased polyp detection. Radiologists should be protected from requirements to report too many CTCs or too quickly. KEY POINTS: • CT colonography services should protect radiologists from a need to report too fast (> 20 min per case) or for too long (> 4 cases consecutively without a break). • Professional bodies should consider introducing a target minimum interpretation time for CT colonography examinations as a quality marker.

Quantified Terminal Ileal Motility during MR Enterography as a Biomarker of Crohn Disease Activity: Prospective Multi-Institution Study.

Purpose To evaluate the accuracy of MRI-quantified small bowel motility for Crohn disease activity against endoscopic and histopathologic reference standards. Materials and Methods For this prospective study, 82 participants (median age, 31 years; range, 16 to 70 years; 42 males [median age, 31 years; range, 17 to 70 years] and 40 females [median age, 31 years; range, 16 to 63 years) underwent colonoscopy and MR enterography within 14 days (from October 2011 to March 2014) at two centers. The Crohn disease endoscopic index of severity (CDEIS), histopathologic activity score (endoscopic biopsy acute histologic inflammatory score [EAIS]), and MR index of activity (MaRIA) were scored in the terminal ileum. Terminal ileal motility was quantified by using an image registration based-motility assessment algorithm (hereafter, Motility). Sensitivity and specificity of Motility (˂0.3 arbitrary units) and MaRIA (≥7 and ≥11) for disease activity (CDEIS ≥4 or EAIS ≥1) were compared by using the McNemar test. Receiver operating characteristic curves were constructed and areas under the curve were compared. Motility was correlated with reference standards by using Spearman rank estimates. Results Terminal ileal Motility was negatively correlated with EAIS (r =-0.61; 95% confidence interval [CI]: 0.7, -0.5) and CDEIS (r = -0.59; 95% CI: 0.7, -0.4). With CDEIS as the standard of reference, Motility had higher sensitivity than did MaRIA (≥11) (93% vs 78%, respectively; P = .03), but lower specificity (61% vs 81%, respectively; P = .04). With EAIS as the standard of reference, Motility had higher sensitivity than did MaRIA (≥7) (92% vs 75%, respectively; P = .03) but similar specificity (71% vs 74%, respectively; P >.99). The area under the receiver operating characteristic curve for Motility was 0.86 and 0.87 with CDEIS and EAIS as the standard of reference, respectively. Conclusion The terminal ileal Motility score showed good agreement with endoscopic and histopathologic activity in Crohn disease. © RSNA, 2018 Online supplemental material is available for this article.

World Endoscopy Organization Consensus Statements on Post-Colonoscopy and Post-Imaging Colorectal Cancer.

BACKGROUND & AIMS: Colonoscopy examination does not always detect colorectal cancer (CRC)- some patients develop CRC after negative findings from an examination. When this occurs before the next recommended examination, it is called interval cancer. From a colonoscopy quality assurance perspective, that term is too restrictive, so the term post-colonoscopy colorectal cancer (PCCRC) was created in 2010. However, PCCRC definitions and methods for calculating rates vary among studies, making it impossible to compare results. We aimed to standardize the terminology, identification, analysis, and reporting of PCCRCs and CRCs detected after other whole-colon imaging evaluations (post-imaging colorectal cancers [PICRCs]). METHODS: A 20-member international team of gastroenterologists, pathologists, and epidemiologists; a radiologist; and a non-medical professional met to formulate a series of recommendations, standardize definitions and categories (to align with interval cancer terminology), develop an algorithm to determine most-plausible etiologies, and develop standardized methodology to calculate rates of PCCRC and PICRC. The team followed the Appraisal of Guidelines for Research and Evaluation II tool. A literature review provided 401 articles to support proposed statements; evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. The statements were voted on anonymously by team members, using a modified Delphi approach. RESULTS: The team produced 21 statements that provide comprehensive guidance on PCCRCs and PICRCs. The statements present standardized definitions and terms, as well as methods for qualitative review, determination of etiology, calculation of PCCRC rates, and non-colonoscopic imaging of the colon. CONCLUSIONS: A 20-member international team has provided standardized methods for analysis of etiologies of PCCRCs and PICRCs and defines its use as a quality indicator. The team provides recommendations for clinicians, organizations, researchers, policy makers, and patients.

Colon cancer screening with CT colonography: logistics, cost-effectiveness, efficiency and progress.

Colorectal cancer (CRC) incidence and mortality can be significantly reduced by population screening. Several different screening methods are currently in use, and this review focuses specifically on the imaging technique computed tomographic colonography (CTC). The challenges and logistics of CTC screening, as well as the importance of test accuracy, uptake, quality assurance and cost-effectiveness will be discussed. With comparable advanced adenoma detection rates to colonoscopy (the most commonly used whole-colon investigation), CTC is a less-invasive alternative, requiring less laxative, and with the potential benefit that it permits assessment of extra colonic structures. Three large-scale European trials have contributed valuable evidence supporting the use of CTC in population screening, and highlight the importance of selecting appropriate clinical management pathways based on initial CTC findings. Future research into CTC-screening will likely focus on radiologist training and CTC quality assurance, with identification of evidence-based key performance indicators that are associated with clinically-relevant outcomes such as the incidence of post-test interval cancers (CRC occurring after a presumed negative CTC). In comparison to other CRC screening techniques, CTC offers a safe and accurate option that is particularly useful when colonoscopy is contraindicated. Forthcoming cost-effectiveness analyses which evaluate referral thresholds, the impact of extra-colonic findings and real-world uptake will provide useful information regarding the feasibility of future CTC population screening.

Diagnostic accuracy of magnetic resonance enterography and small bowel ultrasound for the extent and activity of newly diagnosed and relapsed Crohn's disease (METRIC): a multicentre trial.

BACKGROUND: Magnetic resonance enterography (MRE) and ultrasound are used to image Crohn's disease, but their comparative accuracy for assessing disease extent and activity is not known with certainty. Therefore, we did a multicentre trial to address this issue. METHODS: We recruited patients from eight UK hospitals. Eligible patients were 16 years or older, with newly diagnosed Crohn's disease or with established disease and suspected relapse. Consecutive patients had MRE and ultrasound in addition to standard investigations. Discrepancy between MRE and ultrasound for the presence of small bowel disease triggered an additional investigation, if not already available. The primary outcome was difference in per-patient sensitivity for small bowel disease extent (correct identification and segmental localisation) against a construct reference standard (panel diagnosis). This trial is registered with the International Standard Randomised Controlled Trial, number ISRCTN03982913, and has been completed. FINDINGS: 284 patients completed the trial (133 in the newly diagnosed group, 151 in the relapse group). Based on the reference standard, 233 (82%) patients had small bowel Crohn's disease. The sensitivity of MRE for small bowel disease extent (80% [95% CI 72-86]) and presence (97% [91-99]) were significantly greater than that of ultrasound (70% [62-78] for disease extent, 92% [84-96] for disease presence); a 10% (95% CI 1-18; p=0·027) difference for extent, and 5% (1-9; p=0·025) difference for presence. The specificity of MRE for small bowel disease extent (95% [85-98]) was significantly greater than that of ultrasound (81% [64-91]); a difference of 14% (1-27; p=0·039). The specificity for small bowel disease presence was 96% (95% CI 86-99) with MRE and 84% (65-94) with ultrasound (difference 12% [0-25]; p=0·054). There were no serious adverse events. INTERPRETATION: Both MRE and ultrasound have high sensitivity for detecting small bowel disease presence and both are valid first-line investigations, and viable alternatives to ileocolonoscopy. However, in a national health service setting, MRE is generally the preferred radiological investigation when available because its sensitivity and specificity exceed ultrasound significantly. FUNDING: National Institute of Health and Research Health Technology Assessment.

Imaging complex ventral hernias, their surgical repair, and their complications.

Complex ventral hernia (CVH) describes large, anterior, ventral hernias. The incidence of CVH is rising rapidly due to increasing laparotomy rates in ever older, obese and co-morbid patients. Surgeons with a specific interest in CVH repair are now frequently referring these patients for imaging, normally computed tomography scanning. This review describes what information is required from preoperative imaging and the surgical options and techniques used for CVH repair, so that radiologists understand the postoperative appearances specific to CVH and are aware of the common complications following surgery. KEY POINTS: • Complex ventral hernia (CVH) describes large abdominal wall hernias (e.g. width ≥10cm). • CVH patients are being referred increasingly for preoperative and postoperative imaging. • Imaging is pivotal to characterise preoperative morphology and quantify loss of domain. • Postoperative imaging appearances are contingent on the surgical methods used for CVH repair. • Postoperative complications are depicted easily by imaging.