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.

Definitions for Loss of Domain: An International Delphi Consensus of Expert Surgeons.

BACKGROUND: No standardized written or volumetric definition exists for 'loss of domain' (LOD). This limits the utility of LOD as a morphological descriptor and as a predictor of peri- and postoperative outcomes. Consequently, our aim was to establish definitions for LOD via consensus of expert abdominal wall surgeons. METHODS: A Delphi study involving 20 internationally recognized abdominal wall reconstruction (AWR) surgeons was performed. Four written and two volumetric definitions of LOD were identified via systematic review. Panelists completed a questionnaire that suggested these definitions as standardized definitions of LOD. Consensus on a preferred term was pre-defined as achieved when selected by ≥80% of panelists. Terms scoring <20% were removed. RESULTS: Voting commenced August 2018 and was completed in January 2019. Written definition: During Round 1, two definitions were removed and seven new definitions were suggested, leaving nine definitions for consideration. For Round 2, panelists were asked to select all appealing definitions. Thereafter, common concepts were identified during analysis, from which the facilitators advanced a new written definition. This received 100% agreement in Round 3. Volumetric definition: Initially, panelists were evenly split, but consensus for the Sabbagh method was achieved. Panelists could not reach consensus regarding a threshold LOD value that would preclude surgery. CONCLUSIONS: Consensus for written and volumetric definitions of LOD was achieved from 20 internationally recognized AWR surgeons. Adoption of these definitions will help standardize the use of LOD for both clinical and academic activities.

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.

Nomenclature in Abdominal Wall Hernias: Is It Time for Consensus?

Abdominal wall reconstruction is a rapidly evolving area of surgical interest. Due to the increase in prevalence and size of ventral hernias and the high recurrence rates, the academic community has become motivated to find the best reconstruction techniques. Whilst interrogating the abdominal wall reconstruction literature, we discovered an inconsistency in hernia nomenclature that must be addressed. The terms used to describe the anatomical planes of mesh implantation 'inlay', 'sublay' and 'underlay' are misinterpreted throughout. We describe the misinterpretation of these terms and give evidence of where it exists in the literature. We give three critical arguments of why these misinterpretations hinder advances in abdominal wall reconstruction research. The correct definitions of the anatomical planes, and their respective terms, are described and illustrated. Clearly defined nomenclature is required as academic surgeons strive to improve abdominal wall reconstruction outcomes and lower complication rates.

METRIC (MREnterography or ulTRasound in Crohn's disease): a study protocol for a multicentre, non-randomised, single-arm, prospective comparison study of magnetic resonance enterography and small bowel ultrasound compared to a reference standard in those aged 16 and over.

BACKGROUND: Crohn's disease (CD) is a lifelong, relapsing and remitting inflammatory condition of the intestine. Medical imaging is crucial for diagnosis, phenotyping, activity assessment and detecting complications. Diverse small bowel imaging tests are available but a standard algorithm for deployment is lacking. Many hospitals employ tests that impart ionising radiation, of particular concern to this young patient population. Magnetic resonance enterography (MRE) and small bowel ultrasound (USS) are attractive options, as they do not use ionising radiation. However, their comparative diagnostic accuracy has not been compared in large head to head trials. METRIC aims to compare the diagnostic efficacy, therapeutic impact and cost effectiveness of MRE and USS in newly diagnosed and relapsing CD. METHODS: METRIC (ISRCTN03982913) is a multicentre, non-randomised, single-arm, prospective comparison study. Two patient cohorts will be recruited; those newly diagnosed with CD, and those with suspected relapse. Both will undergo MRE and USS in addition to other imaging tests performed as part of clinical care. Strict blinding protocols will be enforced for those interpreting MRE and USS. The Harvey Bradshaw index, C-reactive protein and faecal calprotectin will be collected at recruitment and 3 months, and patient experience will be assessed via questionnaires. A multidisciplinary consensus panel will assess all available clinical and imaging data up to 6 months after recruitment of each patient and will define the standard of reference for the presence, localisation and activity of disease against which the diagnostic accuracy of MRE and USS will be judged. Diagnostic impact of MRE and USS will be evaluated and cost effectiveness will be assessed. The primary outcome measure is the difference in per patient sensitivity between MRE and USS for the correct identification and localisation of small bowel CD. DISCUSSION: The trial is open at 5 centres with 46 patients recruited. We highlight the importance of stringent blinding protocols in order to delineate the true diagnostic accuracy of both imaging tests and discuss the difficulties of diagnostic accuracy studies in the absence of a single standard of reference, describing our approach utilising a consensus panel whilst minimising incorporation bias. TRIAL REGISTRATION: METRIC - ISRCTN03982913 - 05.11.13.

Anatomical Variation of Abdominal Wall Musculature: An Objective Assessment Using Cross-Sectional Imaging.

Purpose: To determine normal anatomical variation of abdominal wall musculature. Methods: A retrospective analysis of CT scans was performed on adults (>18 years) with normal abdominal wall muscles. Two radiologists analysed the images independently. Distances from three fixed points in the midline were measured. The fixed points were; P1, mid-way between xiphoid and umbilicus, P2, at the umbilicus, and P3, mid-way between umbilicus and pubic symphysis. From these three fixed points the following measurements were recorded; midline to lateral innermost border of the abdominal wall musculature, midline to lateral edge of rectus abdominis muscle, and midline to medial edges of all three lateral abdominal wall muscles. To obtain aponeurotic width, rectus abdominis width was subtracted from the distance to medial edge of lateral abdominal wall muscle. Results: Fifty normal CT scan were evaluated from between March 2023 to August 2023. Mean width of external oblique aponeurosis at P1 was 16.2 mm (IQR 9.2 mm to 20.7 mm), at P2 was 23.5 mm (IQR 14 mm to 33 mm), and at P3 no external oblique muscle was visible. Mean width of the internal oblique aponeurosis at P1 was 32.1 mm (IQR 17.5 mm to 45 mm), at P2 was 10.13 (IQR 1 mm to 17.5 mm), and at P3 was 9.2 mm (IQR 3.0 mm to 13.7 mm). Mean width of the transversus abdominis aponeurosis at P1 was -25.1 mm (IQR 37.8 mm to -15.0 mm), at P2 was 29.4 mm (IQR 20 mm to 39.8 mm), and at P3 was 20.3 mm (IQR 12 mm to 29 mm). Conclusion: In this study we describe normal anatomical variation of the abdominal wall muscles. Assessing this variability on the pre-operative CT scans of ventral hernia patients allows for detailed operative planning and decision making.

A Systematic Review Examining the Experimental Methodology Behind In Vivo Testing of Hiatus Hernia and Diaphragmatic Hernia Mesh.

INTRODUCTION: Mesh implants are regularly used to help repair both hiatus hernias (HH) and diaphragmatic hernias (DH). In vivo studies are used to test not only mesh safety, but increasingly comparative efficacy. Our work examines the field of in vivo mesh testing for HH and DH models to establish current practices and standards. METHOD: This systematic review was registered with PROSPERO. Medline and Embase databases were searched for relevant in vivo studies. Forty-four articles were identified and underwent abstract review, where 22 were excluded. Four further studies were excluded after full-text review-leaving 18 to undergo data extraction. RESULTS: Of 18 studies identified, 9 used an in vivo HH model and 9 a DH model. Five studies undertook mechanical testing on tissue samples-all uniaxial in nature. Testing strip widths ranged from 1-20 mm (median 3 mm). Testing speeds varied from 1.5-60 mm/minute. Upon histology, the most commonly assessed structural and cellular factors were neovascularisation and macrophages respectively (n = 9 each). Structural analysis was mostly qualitative, where cellular analysis was equally likely to be quantitative. Eleven studies assessed adhesion formation, of which 8 used one of four scoring systems. Eight studies measured mesh shrinkage. DISCUSSION: In vivo studies assessing mesh for HH and DH repair are uncommon. Within this relatively young field, we encourage surgical and materials testing institutions to discuss its standardisation.

Temporary sacral nerve stimulation alters rectal sensory function: a physiological study.

BACKGROUND: The indications for sacral nerve stimulation are increasing, but the mechanism remains poorly understood. OBJECTIVE: This study aimed to examine the effect of sacral nerve stimulation on rectal compliance and rectal sensory function. DESIGN: This was a prospective study. SETTINGS: This study took place at a university teaching hospital. PATIENTS: Twenty-three consecutive consenting patients (22 female; median age, 49 y) undergoing temporary sacral nerve stimulation for fecal incontinence were prospectively studied. Clinical response was assessed by the use of bowel diaries and Wexner scores. MAIN OUTCOME MEASURES: Anal manometry, rectal compliance, volume and pressure thresholds to rectal distension (barostat), and rectal Doppler mucosal blood flow were measured before and at the end of stimulation. RESULTS: Sixteen patients (70%) had a favorable clinical response. Median anal squeeze pressures increased with stimulation from 40 (range, 6-156) cmH2O to 64 (range, 16-243) cmH2O. Median rectal compliance did not significantly change with stimulation (prestimulation: 11.5 (range, 7.9-21.8) mL/mmHg, poststimulation: 12.4 (range, 6.2-22) mL/mmHg, P = .941). Rectal wall pressures associated with urge (baseline: 15.4 (range, 11-26.7) mmHg, poststimulation: 19 (range, 11.1-42.7) mmHg, P = .054) and maximal tolerated thresholds (baseline: 21.6 (8.5-31.9) mmHg, poststimulation: 27.1 (14.3-43.3) mmHg, P = .023) significantly increased after stimulation. Rectal Doppler mucosal blood flow did not significantly change with stimulation (baseline: 125.8 (69.9-346.8), poststimulation: 112.4 (50.2-404.1), P = .735). Changes in anal resting pressure and rectal wall pressures with stimulation were evident only in responders; however, changes in anal squeeze pressures were evident in both responders and nonresponders. LIMITATIONS: The study reports results following short-term stimulation in a small but homogenous group of patients. A larger long-term study will follow. CONCLUSION: Temporary sacral nerve stimulation does not change rectal compliance, but is associated with significant changes to the pressure thresholds of rectal distension. This, together with the observation that outcome is not related to sphincter integrity, supports the hypothesis of an afferent-mediated mechanism of action.

The Use of Botulinum Toxin in Complex Hernia Surgery: Achieving a Sense of Closure.

Abdominal wall surgeons have developed a host of tools to help facilitate fascial closure. Botulinum toxin A is one of the most recently identified treatments and has grown in popularity over recent years; showing great promise in a number of case series and cohort studies. The toxin paralyses lateral abdominal wall muscles in order to increase laxity of the tissues-facilitating medialisation of the rectus muscles. Several research groups around the world are developing expertise with its use-uncovering its potential. We present a review of the relevant literature over the last two decades, summarising the key evidence behind its indications, dosing and effects.

Surgical Site Infection: The Scourge of Abdominal Wall Reconstruction.

Background: Surgical site infection (SSI) is a well-recognized and potentially catastrophic complication of abdominal wall reconstruction (AWR). The authors present a review of the literature surrounding SSI in AWR, exploring prevention and treatment strategies as well as risk factors. Methods: A comprehensive review of the current literature was undertaken. Evidence was reviewed and summarized with particular focus on prevention and treatment strategies available to hernia surgeons. Results: Patient risk factors for SSI are well described in the literature and include obesity, smoking, and other comorbidities. Contaminated hernias and cases involving enterocutaneous fistulae are also at higher risk of SSI. Surgical decisions such as type of mesh, plane of mesh placement, and fascial release may all contribute to SSI risk. To treat established mesh infection, conservative management with antibiotic agents and negative pressure therapy is a reasonable option in some cases. Removal of prosthesis appears to provide favorable results, however, repeat surgery can be problematic Conclusions: Surgical site infection remains an important pathology in the world of AWR. Surgeons have a wealth of tools in their arsenal to prevent and treat SSI and should be aware of the emerging evidence in the fast-moving specialty of hernia surgery. Complex cases should be handled by surgeons and centers with expertise in treating such patients.

Inflammation and fibrosis in Crohn's disease: location-matched histological correlation of small bowel ultrasound features.

PURPOSE: To evaluate the utility of mural and extramural sonographic features of Crohn's Disease as potential imaging biomarkers of inflammation and fibrosis against whole-mount histological sections. METHODS: Twelve Crohn's disease patients (Mean age 35(25-69), 7 males) underwent small bowel ultrasound prior to small bowel resection. Two radiologists in consensus graded multiple parameters including mural, mucosal and submucosal thickness, submucosal/mesenteric echogenicity and clarity and mural Doppler signal in 50 selected bowel cross-sections. Matching with histological sampling sites was facilitated via scanning of the resected specimen. A histopathologist scored acute and chronic inflammation, and fibrosis (using histological scoring systems) following analysis of whole mount block sections. The association between sonographic observations and histopathological scores was examined via univariable and multivariable analysis. RESULTS: In univariate analyses, bowel wall thickness (regression co-efficient and 95% CI 0.8 (0.3, 1.3) p = 0.001), mesenteric fat echogenicity (8.7(3.0, 14.5) p = 0.005), submucosal layer thickness (7.4(1.2, 13.5) p = 0.02), submucosal layer clarity (4.4(0.6, 8.2) p = 0.02) and mucosal layer thickness (4.6(1.8, 7.4) p = 0.001) were all significantly associated with acute inflammation. Mesenteric fat echogenicity (674(8.67, 52404) p = 0.009), submucosal layer thickness (79.9(2.16, 2951) p = 0.02) and mucosal layer thickness (13.6(1.54, 121) p = 0.02) were significantly associated with chronic inflammation. Submucosal layer echogenicity (p = 0.03), clarity (25.0(1.76, 356) p = 0.02) and mucosal layer thickness (53.8(3.19, 908) p = 0.006) were significantly associated with fibrosis. In multivariate analyses, wall and mucosal thickness remained significantly associated with acute inflammation (p = 0.02), mesenteric fat echogenicity with chronic inflammation (p = 0.009) and mucosal thickness (p = 0.006) with fibrosis. CONCLUSION: Multiple sonographic parameters are associated with histological phenotypes in Crohn's disease although there is overlap between ultrasonic stigmata of acute inflammation, chronic inflammation and fibrosis.

The management of enterocutaneous fistula in a regional unit in the United kingdom: a prospective study.

BACKGROUND: Enterocutaneous fistula associated with type 2 intestinal failure is a challenging condition that involves a multidisciplinary approach to management. It is suggested that complex cases should only be managed in select national centers in the United Kingdom. METHODS: Over an 18-month period, we prospectively studied all patients referred to us with established enterocutaneous fistulas. Patients followed standardized protocols. Eradication of sepsis, appropriate wound management, establishment of nutritional support, and restoration of normal physiology were attempted. Definitive surgical management was deferred for at least 6 months after the last abdominal surgical intervention. Follow-up was for a minimum of 6 months. RESULTS: Of 55 patients, 10 were internal referrals and 45 were from institutions elsewhere. The mean age was 50 years. Nine patients had colonic fistulas. Forty-six had small bowel fistulas; 19 of these (35%) were associated with inflammatory bowel disease. Patients had undergone a median of 3 previous operations. Four fistulas (7%) healed spontaneously. Thirty-five patients (63%) underwent definitive surgery. Recurrent fistula occurred in 4 patients (13%); 1 required further surgery, and 3 healed spontaneously. The overall mortality rate was 7% (4/55 patients), with 3 patients dying before definitive surgery and 1 patient dying postoperatively. CONCLUSIONS: Our results compare favorably with data from designated national centers (overall mortality, 9.5%-10.8%; operative mortality, 3%-3.5%), suggesting that these patients can be effectively managed in regional units that have sufficient expertise, interest, and volume of patients. Rationalization of funding and referral of patients with type 2 intestinal failure to regional centers may allow national centers to conserve their scarce resources.

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.

Outcomes of a new slowly resorbable biosynthetic mesh (Phasix™) in potentially contaminated incisional hernias: A prospective, multi-center, single-arm trial.

BACKGROUND: Resorbable biomaterials have been developed to reduce the amount of foreign material remaining in the body after hernia repair over the long-term. However, on the short-term, these resorbable materials should render acceptable results with regard to complications, infections, and reoperations to be considered for repair. Additionally, the rate of resorption should not be any faster than collagen deposition and maturation; leading to early hernia recurrence. Therefore, the objective of this study was to collect data on the short-term performance of a new resorbable biosynthetic mesh (Phasix™) in patients requiring Ventral Hernia Working Group (VHWG) Grade 3 midline incisional hernia repair. MATERIALS AND METHODS: A prospective, multi-center, single-arm trial was conducted at surgical departments in 15 hospitals across Europe. Patients aged ≥18, scheduled to undergo elective Ventral Hernia Working Group Grade 3 hernia repair of a hernia larger than 10 cm2 were included. Hernia repair was performed with Phasix™ Mesh in sublay position when achievable. The primary outcome was the rate of surgical site occurrence (SSO), including infections, that required intervention until 3 months after repair. RESULTS: In total, 84 patients were treated with Phasix™ Mesh. Twenty-two patients (26.2%) developed 32 surgical site occurrences. These included 11 surgical site infections, 9 wound dehiscences, 7 seromas, 2 hematomas, 2 skin necroses, and 1 fistula. No significant differences in surgical site occurrence development were found between groups repaired with or without component separation technique, and between clean-contaminated or contaminated wound sites. At three months, there were no hernia recurrences. CONCLUSION: Phasix™ Mesh demonstrated acceptable postoperative surgical site occurrence rates in patients with a Ventral Hernia Working Group Grade 3 hernia. Longer follow-up is needed to evaluate the recurrence rate and the effects on quality of life. This study is ongoing through 24 months of follow-up.

Mural Crohn disease: correlation of dynamic contrast-enhanced MR imaging findings with angiogenesis and inflammation at histologic examination--pilot study.

PURPOSE: To determine mural perfusion dynamics in Crohn disease by using dynamic contrast material-enhanced magnetic resonance (MR) imaging and to correlate these with histopathologic markers of inflammation and angiogenesis. MATERIALS AND METHODS: Ethical permission was given by the University College London Hospital ethics committee, and informed consent was obtained from all participants. Eleven consecutive patients with Crohn disease (eight female patients, three men; mean age, 39.5 years; range, 16.4-66.6 years) undergoing elective small-bowel resection were recruited between July 2006 and December 2007. Harvey-Bradshaw index, C-reactive protein (CRP) level, and disease chronicity were recorded. Preoperatively, dynamic contrast-enhanced MR imaging was performed through the section of bowel destined for resection, and slope of enhancement, time to maximum enhancement, enhancement ratio, the volume transfer coefficient K(trans), and the extracellular volume fraction v(e) were calculated for the affected segment. Ex vivo surgical specimens were imaged to facilitate imaging-pathologic correlation. Histopathologic sampling of the specimen was performed through the imaged tissue, and microvascular density (MVD) was determined, together with acute and chronic inflammation scores. Correlations between clinical, MR imaging, and histopathologic data were made by using the Kendall rank correlation and linear regression. RESULTS: Disease chronicity was positively correlated with enhancement ratio (correlation coefficient, 0.82; P = .002). Slope of enhancement demonstrated a significant negative correlation with MVD (correlation coefficient, -0.86; P < .001). There was a negative correlation between CRP level and slope of enhancement (correlation coefficient, -0.77; P = .006). Neither acute nor chronic inflammation score correlated with any other parameter. CONCLUSION: Certain MR imaging-derived mural hemodynamic parameters correlate with disease chronicity and angiogenesis in Crohn disease, but not with histologic and clinical markers of inflammation. Data support the working hypothesis that microvessel permeability increases with disease chronicity and that tissue MVD is actually inversely related to mural blood flow.

Mural inflammation in Crohn disease: location-matched histologic validation of MR imaging features.

PURPOSE: To validate proposed magnetic resonance (MR) imaging features of Crohn disease activity against a histopathologic reference. MATERIALS AND METHODS: Ethical permission was given by the University College London hospital ethics committee, and informed written consent was obtained from all participants. Preoperative MR imaging was performed in 18 consecutive patients with Crohn disease undergoing elective small-bowel resection. The Harvey-Bradshaw index, the C-reactive protein level, and disease chronicity were recorded. The resected bowel was retrospectively identified at preoperative MR imaging, and wall thickness, mural and lymph node/cerebrospinal fluid (CSF) signal intensity ratios on T2-weighted fat-saturated images, gadolinium-based contrast material uptake, enhancement pattern, and mesenteric signal intensity on T2-weighted fat-saturated images were recorded. Precise histologic matching was achieved by imaging the ex vivo surgical specimens. Histopathologic grading of acute inflammation with the acute inflammatory score (AIS) (on the basis of mucosal ulceration, edema, and quantity and depth of neutrophilic infiltration) and the degree of fibrostenosis was performed at each site, and results were compared with MR imaging features. Data were analyzed by using linear regression with robust standard errors of the estimate. RESULTS: AIS was positively correlated with mural thickness and mural/CSF signal intensity ratio on T2-weighted fat-saturated images (P < .001 and P = .003, respectively) but not with mural enhancement at 30 and 70 seconds (P = .50 and P = .73, respectively). AIS was higher with layered mural enhancement (P < .001), a pattern also commonly associated with coexisting fibrostenosis (75%). Mural/CSF signal intensity ratio on T2-weighted fat-saturated images was higher in histologically edematous bowel than in nonedematous bowel (P = .04). There was no correlation between any lymph node characteristic and AIS. CONCLUSION: Increasing mural thickness, high mural signal intensity on T2-weighted fat-saturated images, and a layered pattern of enhancement reflect histologic features of acute small-bowel inflammation in Crohn disease.

Classification--important step to improve management of patients with an open abdomen.

This short report is a distillation of the proceedings from a consensus group meeting in January 2009. It outlines a proposed classification system for patients with an open abdomen (OA). The classification allows (1) a description of the patient's clinical course; (2) standardized clinical guidelines for improving OA management; and (3) improved reporting of OA status, which will facilitate comparisons between studies and heterogeneous patient populations. The following grading is suggested: grade 1A, clean OA without adherence between bowel and abdominal wall or fixity of the abdominal wall (lateralization); grade 1B, contaminated OA without adherence/fixity; grade 2A, clean OA developing adherence/fixity; grade 2B, contaminated OA developing adherence/fixity; grade 3, OA complicated by fistula formation; grade 4, frozen OA with adherent/fixed bowel, unable to close surgically, with or without fistula. We propose that this classification system will facilitate communication, clarify OA management, and potentially improve patient care.

Marathon-induced ischemic colitis: why running is not always good for you.

We present the case of a 31 year-old man who presented to the emergency department of University College Hospital London after collapsing upon finishing the London marathon. Contrast-enhanced multidetector computed tomography scanning revealed ischemic colitis of the cecum and ascending colon, which progressed to the development of clinical peritonism after 48 hours. This patient subsequently underwent a laparotomy and right hemicolectomy, with ileostomy formation, on the third day after admission. Operative and histologic findings confirmed ischemic colitis of the cecum and proximal colon. The postoperative recovery was uneventful, and he was discharged home well. Possible mechanisms of ischemia in marathon runners and those undergoing intense exercise include a combination of splanchnic vasoconstriction, dehydration, and hyperthermia, combined with mechanical forces. Most patients presenting with marathon-running-induced ischemic colitis respond to conservative treatment and the need for operative intervention is extremely rare.