Prospective comparison of computed tomography enterography and magnetic resonance enterography for assessment of disease activity and complications in ileocolonic Crohn's disease

Medical radiation exposure in inflammatory bowel disease: an updated meta-analysis

BACKGROUND

There have been previous studies and earlier systematic review on the relationship between inflammatory bowel disease (IBD) and radiation exposure. With the diversification of current test methods, this study intended to conduct a meta-analysis to evaluate the IBD radiation exposure in recent years.

METHODS

Three databases (PUBMED, EMBASE, and MEDICINE) for relevant literature up to May 1, 2023 were searched. The statistical data meeting requirements were collated and extracted.

RESULTS

20 papers were enrolled. The overall high radiation exposure rate was 15% (95% CI = [12%, 19%]) for CD and 5% (95% CI = [3%, 7%]) for UC. The pooled result found that high radiation exposure rate was 3.44 times higher in CD than in UC (OR = 3.44, 95% CI = [2.35, 5.02]). Moreover, the average radiation exposure level in CD was 12.77 mSv higher than that in UC (WMD = 12.77, 95% CI = [9.93, 15.62] mSv). Furthermore, radiation exposure level of CD after 2012 was higher than those before 2012 (26.42 ± 39.61vs. 23.76 ± 38.46 mSv, P = 0.016), while UC did not show similar result (11.99 ± 27.66 vs. 10.01 ± 30.76 mSv, P = 0.1). Through subgroup analysis, it was found that disease duration (WMD = 2.75, 95% CI = [0.10, 5.40] mSv), complications (OR = 5.09, 95% CI = [1.50, 17.29]), and surgical history (OR = 5.46, 95% CI = [1.51, 19.69]) significantly increased the proportion of high radiation exposure.

CONCLUSION

This study found that radiation exposure level of IBD patients was high, which revealed the radiation risk in the process of diagnosis and treatment of IBD patients. In the future, longer follow-up and prospective studies are needed to reveal the relationship between high radiation exposure and solid tumorigenesis.

Peri-Operative Optimization of Patients with Crohn's Disease

PURPOSE OF REVIEW

The management of patients with Crohn's disease (CD) undergoing surgery is complex and optimization of modifiable factors perioperatively can improve outcomes. This review focuses on the perioperative management of CD patients undergoing surgery, emphasizing the need for a multi-disciplinary approach.

RECENT FINDINGS

Research highlights the benefits of a comprehensive strategy, involving nutritional optimization, psychological assessment, and addressing septic complications before surgery. Despite many CD patients being on immune-suppressing medications, studies indicate that most of these medications are safe to use and should not delay surgery. However, a personalized approach for each case is needed. This review underscores the importance of multi-disciplinary team led peri-operative management of CD patients. We suggest that this can be done at a dedicated perioperative clinic for prehabilitation, with the potential to enhance outcomes for CD patients undergoing surgery.

Current Approach to Risk Factors and Biomarkers of Intestinal Fibrosis in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), especially Crohn's disease (CD), characterized by a chronic inflammatory process and progressive intestinal tissue damage, leads to the unrestrained proliferation of mesenchymal cells and the development of bowel strictures. Complications induced by fibrosis are related to high rates of morbidity and mortality and lead to a substantial number of hospitalizations and surgical procedures, generating high healthcare costs. The development of easily obtained, reliable fibrogenesis biomarkers is essential to provide an important complementary tool to existing diagnostic and prognostic methods in IBD management, guiding decisions on the intensification of pharmacotherapy, proceeding to surgical methods of treatment and monitoring the efficacy of anti-fibrotic therapy in the future. The most promising potential markers of fibrosis include cartilage oligomeric matrix protein (COMP), hepatocyte growth factor activator (HGFA), and fibronectin isoform- extra domain A (ED-A), as well as antibodies against granulocyte macrophage colony-stimulating factor (GM-CSF Ab), cathelicidin (LL-37), or circulatory miRNAs: miR-19a-3p and miR-19b-3p. This review summarizes the role of genetic predisposition, and risk factors and serological markers potentially contributing to the pathophysiology of fibrotic strictures in the course of IBD.

Analysis of the Accuracy of Magnetic Resonance Enterography for the Detection of Active Inflammation and Disease Activity in Patients With Crohn's Disease: A Single-Center Experience in Najran, Saudi Arabia

BACKGROUND

Magnetic resonance enterography (MRE) is a non-invasive diagnostic imaging modality that has been used for the detection of active inflammation and disease activity in patients with Crohn's disease. However, its diagnostic accuracy in the Najran population has not been well-studied.

STUDY AIM

This study aimed to assess the diagnostic accuracy of MRE in detecting active inflammation and disease activity in patients with Crohn's disease in the Najran population.

METHODS

The study included 51 patients with Crohn's disease, and their demographic, clinical, radiological, laboratory, and endoscopic data were analyzed.

RESULTS

The results showed that MRE findings, such as the radiological score for active inflammation and the presence of extra-intestinal manifestations, were significantly associated with the final diagnosis of active inflammation. Furthermore, the timing of MRE in relation to symptom activity and the indication for performing MRE were significantly associated with the final diagnosis. The study findings demonstrate the potential of MRE as a valuable tool for diagnosing and assessing disease activity in Crohn's disease patients in the Najran population.

Imaging of Strictures in Crohn's Disease

Crohn's disease (CD) is a chronic inflammation of the digestive tract, and it frequently affects young patients. It can involve any intestinal segment, even though it frequently affects the distal ileum. Up to 80% of patients with CD present with inflammatory behavior, and 5% to 28% develop stricturing disease. Based on the predominant mechanism causing them, strictures can be categorized as inflammatory, fibrotic, or mixed. Determining the relative amounts of inflammation and fibrosis in a stricture can influence treatment decisions. Imaging is an extremely useful tool in patients with small bowel stricturing CD to confirm the diagnosis and to evaluate disease characteristics, usually using CT or MRI. The aim of this paper is to describe how imaging can evaluate a patient with small bowel CD stricture.

Evaluating the diagnostic accuracy of magnetic resonance imaging in distinguishing strictures in Crohn's disease: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis sought to assess the diagnostic accuracy of magnetic resonance imaging (MRI) in distinguishing fibrotic from inflammatory strictures in Crohn's disease (CD) patients.

METHODS

A rigorous and systematic exploration of five key databases yielded studies that met predefined criteria. Data were extracted for a comprehensive meta-analysis using MetaDiSC and MetaDTA software, providing diagnostic accuracy measures. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool was utilized for evaluating the methodological quality and potential bias within the studies.

RESULTS

The systematic review involved the evaluation of 7437 records, culminating in the inclusion of 22 studies. In detecting fibrotic strictures in CD patients, MRI exhibited a pooled sensitivity of 85.20% (95% CI: 76.10-91.20%) and specificity of 96.00% (95% CI: 87.80-98.70%). For differentiating fibrotic strictures from inflammatory stenosis, the sensitivity was 81.5% (95% CI: 70.2-89.20%), and the specificity was 97.2% (95% CI: 90.0-99.3%). In terms of assessing the severity of strictures, sensitivity stood at 90.4% (95% CI: 78.1-96.1%) and specificity at 89.4% (95% CI: 57.4-98.2%). The consistency of the diagnostic accuracy was observed across different geographical locations and the various reference tests applied in the studies.

CONCLUSIONS

The results of this meta-analysis underscore the robust diagnostic accuracy of MRI in detecting fibrotic strictures, distinguishing between fibrotic and inflammatory strictures, and evaluating stricture severity in CD patients. These findings support the integration of MRI into standard diagnostic protocols for patients with CD. Further large-scale, multicenter trials are warranted to confirm these results and to identify any potential limitations associated with the application of MRI in this clinical setting.

Assessment of Ileal Crohn's Disease Activity by Gastrointestinal Ultrasound and MR Enterography: A Pilot Study

INTRODUCTION

In some cases, there may be a discrepancy between the symptomatology alleged by Crohn's disease (CD) patients and the results of laboratory tests or imaging investigations. Ileocolonoscopy with biopsy is the primary investigation for diagnosing and monitoring CD patients. Cross-sectional imaging techniques such as CT or MR enterography (MRE) and intestinal ultrasonography (IUS) have been proposed as complementary methods to colonoscopy for a complete evaluation of this category of patients. This study aims to identify the role of IUS, contrast-enhanced ultrasound (CEUS) and MRE in evaluating ileal CD activity, using clinical severity scores (Crohn's disease activity index-CDAI, Harvey-Bradshaw index-HBI) and faecal calprotectin or C-reactive protein (CRP) levels as reference methods.

MATERIALS AND METHODS

A total of 44 adult patients with ileal CD confirmed using an ileocolonoscopy with biopsy and histopathological examination were assessed by IUS, CEUS and MRE. The evaluation of the disease activity based on the results obtained from the cross-sectional imaging tests was carried out by using some severity scores available in the literature. The sensitivity and specificity of IUS + CEUS and MRE for differentiating active from inactive forms of CD were determined using CDAI, HBI, faecal calprotectin and CRP as reference methods. The accuracy of the results was assessed by the receiver operating characteristics method. The Pearson correlation coefficient was used to determine the types of correlation. A p-value less than 0.05 suggested a statistically significant relationship.

RESULTS

Compared to CDAI, the best correlation was identified for Limberg score (r = 0.667, 95% confidence interval (CI) [0.46, 0.8], p < 0.001), followed by MaRIAs score (r = 0.614, 95% CI [0.39, 0.77], p < 0.001). A sensitivity of 93.33% and a specificity of 71.43% (AUC = 0.98) were demonstrated in the case of Limberg score for differentiating patients with active disease from those in remission and for MaRIAs score a sensitivity of 100.00% and a specificity of 57.14% (AUC = 0.97). Regarding HBI, the best correlation was observed for MaRIAs score (r = 0.594, 95% CI [0.36, 0.76], p < 0.001). Also, faecal calprotectin showed the best correlation with MaRIAs score (r = 0.697, 95% CI [0.46, 0.84], p < 0.001), but in the case of CRP, there was only a weak correlation for all evaluated scores.

CONCLUSIONS

Although magnetic resonance imaging does not appear to be superior to ultrasonography in terms of accuracy for differentiating active forms of CD from those in remission, the results of our study suggest that MRE associates a better correlation with clinical severity scores and faecal calprotectin levels compared to ultrasonography. More studies are needed to validate these results.

Evaluation of symptomatic small bowel stricture in Crohn's disease by double-balloon endoscopy

PURPOSE

To assess the efficacy of double-balloon endoscopy (DBE) for the detection of small-bowel strictures in Crohn's disease (CD).

METHODS

This tertiary-referral hospital cohort study was conducted between January 2018 and May 2022. CD patients with symptoms of small-bowel stricture were enrolled sequentially. All of the patients were subjected to both computed tomography enterography (CTE) and DBE, and their symptoms of stricture were assessed using the Crohn's Disease Obstructive Score (CDOS). The diagnostic yield of DBE was compared to that of CTE, and the relationship between the DBE findings and CDOS was investigated. The factors influencing the DBE diagnosis were examined using Cox regression analysis.

RESULTS

This study included 165 CD patients. The CDOS scores were higher in 95 patients and lower in 70 patients. DBE detected 92.7% (153/165) and CTE detected 85.5% (141/165) of the strictures. The DBE diagnostic yields were 94.7% (90/95) in the high CDOS patients and 91.4% (64/70) in the low CDOS patients (P = 0.13). Patients with a history of abdominal surgery and abscess had a lower diagnosis rate in the multivariate analysis.

CONCLUSION

DBE has been demonstrated to be an efficient diagnostic method for detecting small bowel strictures in CD patients. Additionally, there was no difference in the diagnostic yields between patients with low and high obstructive scores.

Diagnostic accuracy of different cross-sectional imaging techniques for disease location and activity in Crohn's disease and external validation and comparison of MARIAs and IBUS-SAS

PURPOSE

The comparative accuracy of cross-sectional imaging techniques for evaluating Crohn's disease (CD) remains uncertain. This study aimed to assess diagnostic accuracy of disease location and activity in different cross-sectional images and validate and compare International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) and Simplified Magnetic Resonance Index of Activity (MARIAs).

METHODS

CD patients were retrospectively included from August 2018 to May 2021. We compared accuracy of B-mode intestinal ultrasound (B-IUS), computed tomography enterography (CTE), and magnetic resonance enterography (MRE) for the identification of disease location. Meanwhile, disease activity was compared on B-IUS, color Doppler imaging, CTE, and MRE. ROC analyses were used to validate MARIAs and IBUS-SAS. Spearman rank correlation was performed to evaluate the relationships between MARIAs/IBUS-SAS and CDAI, SES-CD, and inflammatory indicators.

RESULTS

A total of 115 CD patients were evaluated. The diagnostic accuracy of MRE in detecting small bowel disease was superior to that of B-IUS/CTE, showing sensitivity (89.3%), specificity (71.4%), and AUC (0.820). B-IUS had the highest sensitivity (81.2%), specificity (84.8%), and AUC (0.830) for detecting terminal ileal lesions. The diagnostic accuracy for colonic disease and disease activity was not significantly different among these techniques. In the validation of IBUS-SAS, the AUC was 0.860, with an optimal cutoff value to predict active disease of 46.7. MARIAs and IBUS-SAS showed no significant differences in the correlations of CDAI, SES-CD, and inflammatory indicators.

CONCLUSION

MRE and B-IUS are more sensitive for detecting small bowel CD and terminal ileal CD, respectively. IBUS-SAS has potential for precisely defining CD activity.

Inflammatory bowel disease cross-sectional imaging: What's new?

Cross-sectional imaging-ultrasonography, computed tomography enterography, and magnetic resonance enterography-is a routine and indispensable tool for patients with Crohn's disease (CD) that helps to detect or monitor disease characteristics before, during, and after CD treatment. New emerging radiological technologies may have further clinical applications in the management of CD. In this review article, we focus on the latest developments in cross-sectional imaging in CD research, including its role in intra- and extra-luminal lesion detection, intestinal inflammation and fibrosis grading, therapeutic response assessment and outcome prediction, postoperative recurrence detection and prediction, and the gut-brain axis.

Imaging Evaluation of Inflammatory Bowel Disease Complications

Inflammatory bowel disease (IBD) is a chronic inflammatory condition that can progress to fibrostenotic and penetrating complications. Cross-sectional imaging is often needed for accurate diagnosis of IBD complication and for planning the appropriate management strategy. Computed tomography enterography, magnetic resonance enterography, and IBD ultrasound have become key tools for clinicians and interventional endoscopists. This article highlights and discusses various radiologic imaging techniques and their application to the diagnosis and management of IBD complications.

Treat to transmural healing: how to incorporate intestinal ultrasound into the treatment of inflammatory bowel disease

Intestinal ultrasound (IUS) is emerging as a key tool to achieving the therapeutic target of transmural healing in inflammatory bowel disease (IBD). IUS is a non-invasive, radiation-free, imaging modality comparable to MRI, CT and ileocolonoscopy (IC). With the appropriate training and equipment, IUS can be an easily repeatable bedside test for IBD diagnosis and disease monitoring, including treatment response. Core to successful high quality IUS employment are appropriate training and expert techniques; however, the training pathway will not be explored in this review. Given the increasing shift towards objective assessment for tight disease control, gastroenterologist-led IUS should be incorporated into the armamentarium of imaging modalities alongside radiologists, to enhance our diagnostic and monitoring toolbox. This comprehensive review aims to outline the current literature around IUS and propose the placement of IUS in a treat-to-target algorithm in IBD. Ultimately, IUS facilitates timely management decisions to optimise patient care with potential to revolutionise patient outcomes, moving towards transmural healing as the holy grail of therapy in IBD.

The Role of Magnetic Resonance Enterography in Crohn’s Disease: A Review of Recent Literature

Inflammatory bowel disease (IBD) is the term used to identify a form of chronic inflammation of the gastrointestinal tract that primarily contemplates two major entities: ulcerative colitis (UC) and Crohn’s disease (CD). The classic signs are abdominal pain and diarrhoea that correlate with the localization of gastro-enteric disease, although in this pathology extraintestinal symptoms may coexist. The diagnosis of CD relies on a synergistic combination of clinical, laboratory (stool and biochemical), cross-sectional imaging evaluation, as well as endoscopic and histologic assessments. The purpose of this paper is to prove the role of imaging in the diagnosis and follow-up of patients with CD with particular focus on recent innovations of magnetic resonance enterography (MRE) as a pivotal diagnostic tool, analysing the MRE study protocol and imaging features during the various phases of disease activity and its complications.

Small bowel Crohn's disease: optimal modality for diagnosis and monitoring

PURPOSE OF REVIEW

This paper reviews different imaging options for small bowel (SB) Crohn's disease (CD) patients.

RECENT FINDINGS

In total, 80% of patients suffering from CD have SB involvement, being the exclusive manifestation in 30% of cases. As the proximal disease is related to poor response to treatment, a higher rate of stenosis and a greater need for surgical treatment, a SB assessment should be performed. This evaluation should be done not only once the disease has been diagnosed but periodically. The former to determine the extent of the disease, and the latter according to a treat-to-target strategy. Available techniques such as magnetic resonance imaging, intestinal ultrasound and capsule endoscopy (CE) have shown good accuracy parameters in CD patients. Cross-sectional studies are superior for penetrating and stricturing disease, whereas CE is excellent for proximal involvement and mucosal healing. Local expertise and availability may lead the election between techniques, nevertheless, they should not be considered as competitors but as complementary tools.

SUMMARY

SB involvement in CD patients is frequent and related to poorer outcomes. Hence, SB evaluation should be screened after diagnosis and routinely during the follow-up.

Appendiceal involvement in pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2): a diagnostic challenge in the coronavirus disease (COVID) era

BACKGROUND

Many studies on pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 (PIMS-TS) have described abdominal findings as part of multisystem involvement, with limited descriptions of abdominal imaging findings specific to PIMS-TS.

OBJECTIVE

To perform a detailed evaluation of abdominal imaging findings in children with PIMS-TS.

MATERIALS AND METHODS

We performed a single-center retrospective study of children admitted to our institution between April 2020 and January 2021 who fulfilled Royal College of Paediatrics and Child Health criteria for PIMS-TS and who had cross-sectional abdominal imaging. We studied clinical data, abdominal imaging, laboratory markers, echocardiography findings, treatment and outcomes for these children. We also reviewed the literature on similar studies.

RESULTS

During the study period, 60 PIMS-TS cases were admitted, of whom 23 required abdominal imaging. Most (74%) were from a Black, Asian or minority ethnic background and they had an average age of 7 years (range 2-14 years). All children had fever and gastrointestinal symptoms on presentation with elevated C-reactive protein, D-dimer and fibrinogen. Most had lymphopenia, raised ferritin and hypoalbuminemia, with positive severe acute respiratory syndrome coronavirus 2 immunoglobulin G antibodies in 65%. Free fluid (78%), right iliac fossa mesenteric inflammation (52%), and significantly enlarged mesenteric lymph nodes (52%) were the most common imaging findings. Appendiceal inflammation (30%) and abnormal distal ileum and cecum/ascending colon wall thickening (35%) were also common. All children responded well to medical management alone, with no mortality.

CONCLUSION

In addition to free fluid, prominent lymphadenopathy, and inflammatory changes in the right iliac fossa, we found abnormal long-segment ileal thickening and appendicitis to be frequent findings. Recognition of appendiceal involvement as a component of the PIMS-TS spectrum should help clinicians avoid unnecessary surgical intervention as part of a multidisciplinary team approach.

Cumulative Effective Dose from Medical Imaging in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) are chronic and relapsing disorders usually requiring numerous medical imaging. IBD patients might be exposed to a large dose of radiation. As a cumulative effective dose (CED) ≥ 50 mSv is considered significant for stochastic risks of cancer, it is important to monitor the radiation exposure of IBD patients. In the present work, we aimed to quantify the mean CED in IBD patients and identify factors associated with exposure to high doses of diagnostic radiation. A retrospective chart view of patients with IBD hospitalized between 2015 and 2019 was performed. A total of 65 patients with Crohn's disease (CD) and 98 patients with ulcerative colitis (UC) were selected. Of all imaging studies performed, 73% were with doses of ionizing radiation. Mean CED (SD) amounted to 19.20 (15.64) millisieverts (mSv) and 6.66 (12.39) mSv, respectively, in patients with CD and UC (p < 0.00001). Only 1.84% of the patients received CED ≥ 50 mSv. We identified three factors associated with CED in the IBD patients: number of surgical procedures, and number and length of hospitalization. CD patients with strictures or penetrating disease and UC patients with extensive colitis were more likely to receive higher radiation doses.

Current noninvasive modalities in Crohn's disease monitoring

Crohn’s disease (CD) is characterized by a remitting and relapsing course. Longstanding active CD may result in accumulating intestinal damage and disease-related complications. In contrast, mucosal healing is associated with significant improvement in the health-related quality of life, longer periods of disease remission and lower risk of disease progression, complications, hospitalizations, intestinal surgeries, as well as a lower risk of developing colorectal cancer. Mucosal healing, the new treatment endpoint in CD, made necessary the development of noninvasive, accurate, objective and reliable tools for the evaluation of CD activity. Ileocolonoscopy with biopsies remains the reference standard method for the evaluation of the colonic and terminal ileal mucosa. However, it is an invasive procedure with a low risk of complications, allowing the investigation of only a small part of the small bowel mucosa without being able to assess transmural inflammation. These disadvantages limit its role in the frequent follow up of CD patients. In this review, we present the currently available biomarkers and imaging modalities for the noninvasive assessment of CD activity.

Diagnostic Accuracy of Magnetic Resonance Enterography in the Evaluation of Colonic Abnormalities in Crohn's Disease: A Systematic Review and Meta-Analysis

OBJECTIVES

To Evaluate the diagnostic performance of magnetic resonance enterography (MRE) for detecting colonic involvement of Crohn's disease (CD).

MATERIALS AND METHODS

A systematic search of the electronic bibliographic databases was conducted. The inclusion criteria of published original articles were: (1) Utilized MRE to evaluate colon; (2) Patients with documented CD by colonoscopy; (3) Provided crude data of diagnostic performance in the large bowel; (4) Performed segmental evaluation. The colorectal segments were defined as the right colon, transverse colon, left colon, and rectum. A hierarchical bivariate method was used for analysis.

RESULTS

Eleven articles (12 populations and 987 patients) were included. The pooled sensitivity and specificity of the studies were 69% (95% CI: 0.52-0.82) and 95% (95% CI:0.92-0.97), respectively (AUC = 0.95). The pooled positive and negative likelihood ratios were 14 (95% CI:7.5-26.3) and 0.31 (95% CI:0.19-0.51), respectively. Regarding segments, the left colon had the highest sensitivity (60%) and lowest specificity (92%), while the transverse colon showed lowest sensitivity (49%) and highest specificity (95%). Comparing the age groups, MRE sensitivity and specificity was 80% and 95%, versus 62% and 94%, in pediatrics and adults respectively.

CONCLUSION

MRE has a high specificity to detect colon pathologies in CD, while the sensitivity is low. Therefore, the test has a high value to rule in CD, while negative results are not sufficient to rule it out. Meanwhile, considering the higher sensitivity rate of the test in pediatrics, it has the potential to be used as a first-line investigation.

The Pathogenesis and Clinical Management of Stricturing Crohn Disease

Stricturing of the gastrointestinal tract is a common complication in Crohn disease and is a significant cause of morbidity and mortality among this population. The inflammatory process initiates fibrosis, leading to aberrant wound healing and excess deposition of extracellular matrix proteins. Our understanding of this process has grown and encompasses cellular mechanisms, epigenetic modifications, and inherent genetic predisposition toward fibrosis. Although medications can improve inflammation, there is still no drug to attenuate scar formation. As such, management of stricturing disease requires a multidisciplinary and individualized approach including medical management, therapeutic endoscopy, and surgery. This review details the current understanding regarding the pathogenesis, detection, and management of stricturing Crohn disease.

Luminal Narrowing Alone Allows an Accurate Diagnosis of Crohn's Disease Small Bowel Strictures at Cross-Sectional Imaging

BACKGROUND AND AIMS

Current consensus recommendations define small bowel strictures [SBS] in Crohn's disease [CD] on imaging as luminal narrowing with unequivocal upstream bowel dilation. The aim of this study was to [1] evaluate the performance of cross-sectional imaging for SBS diagnosis in CD using luminal narrowing with upstream SB dilation and luminal narrowing with or without upstream dilation, and [2] compare the diagnostic performance of computed tomography [CT] and magnetic resonance enterography [MRE] for SBS diagnosis.

METHODS

In total, 111 CD patients [81 with pathologically confirmed SBS, 30 controls] who underwent CT and/or MRE were assessed. Two radiologists [R1, R2] blinded to pathology findings independently assessed the presence of luminal narrowing and upstream SB dilation. Statistical analysis was performed for [1] luminal narrowing with or without SB upstream dilation ['possible SBS'], and [2] luminal narrowing with upstream SB dilation ≥3 cm ['definite SBS'].

RESULTS

Sensitivity for detecting SBS was significantly higher using 'possible SBS' [R1, 82.1%; R2, 77.9%] compared to 'definite SBS' [R1, 62.1%; R2, 65.3%; p < 0.0001] with equivalent specificity [R1, 96.7%; R2, 93.3%; p > 0.9]. Using the criterion 'possible SBS', sensitivity/specificity were equivalent between CT [R1, 87.3%/93.3%; R2, 83.6%/86.7%] and MRE [R1, 75.0%/100%; R2: 70.0%/100%]. Using the criterion 'definite SBS', CT showed significantly higher sensitivity [78.2%] compared to MRE [40.0%] for R1 but not R2 with similar specificities [CT, 86.7-93.3%; MRE, 100%].

CONCLUSION

SBS can be diagnosed using luminal narrowing alone without the need for upstream dilation. CT and MRE show similar diagnostic performance for SBS diagnosis using luminal narrowing with or without upstream dilation.

WSES-AAST guidelines: management of inflammatory bowel disease in the emergency setting

BACKGROUND

Despite the current therapeutic options for the treatment of inflammatory bowel disease, surgery is still frequently required in the emergency setting, although the number of cases performed seems to have decreased in recent years. The World Society of Emergency Surgery decided to debate in a consensus conference of experts, the main pertinent issues around the management of inflammatory bowel disease in the emergent situation, with the need to provide focused guidelines for acute care and emergency surgeons.

METHOD

A group of experienced surgeons and gastroenterologists were nominated to develop the topics assigned and answer the questions addressed by the Steering Committee of the project. Each expert followed a precise analysis and grading of the studies selected for review. Statements and recommendations were discussed and voted at the Consensus Conference of the 6th World Society of Emergency Surgery held in Nijmegen (The Netherlands) in June 2019.

CONCLUSIONS

Complicated inflammatory bowel disease requires a multidisciplinary approach because of the complexity of this patient group and disease spectrum in the emergency setting, with the aim of obtaining safe surgery with good functional outcomes and a decreasing stoma rate where appropriate.

A clinical and radiographic model to predict surgery for acute small bowel obstruction in Crohn's disease

PURPOSE

For more than half of Crohn's disease patients, strictures will cause bowel obstructions that require surgery within 10 years of their initial diagnosis. This study utilizes computed tomography imaging and clinical data obtained at the initial emergency room visit to create a prediction model for progression to surgery in Crohn's disease patients with acute small bowel obstructions.

METHODS

A retrospective chart review was performed for patients who presented to the emergency room with an ICD-10 diagnosis for Crohn's disease and visit diagnosis of small bowel obstruction. Two expert abdominal radiologists evaluated the CT scans for bowel wall thickness, maximal and minimal luminal diameters, length of diseased segment, passage of oral contrast, evidence of penetrating disease, bowel wall hyperenhancement or stratification, presence of a comb sign, fat hypertrophy, and small bowel feces sign. The primary outcome was progression to surgery within 6 months of presentation. The secondary outcome was time to readmission.

RESULTS

Forty patients met the inclusion criteria, with 78% receiving medical treatment alone and 22% undergoing surgery within 6 months of presentation to the emergency room. Multivariable analysis produced a model with an AUC of 92% (95% CI 0.82-1.00), 78% sensitivity, and 97% specificity, using gender, body mass index, and the radiographic features of segment length, penetrating disease, and bowel wall hyperenhancement.

CONCLUSIONS

The model demonstrates that routine clinical and radiographic data from an emergency room visit can predict progression to surgery, and has the potential to risk stratify patients, guide management in the acute setting, and predict readmission.

Prospective comparison of diffusion-weighted magnetic resonance enterography and contrast enhanced computed tomography enterography for the detection of ileocolonic Crohn's disease

BACKGROUND AND AIMS

Crohn's disease (CD) is a chronic and relapsing course with various status of different segments, and there were no investigations comparing the lesion detection between magnetic resonance (MR) and computed tomography (CT) in term of the severity of CD. We aim to assess the performances of diffusion-weighted MR enterography (DW-MRE) and contrast enhanced CT enterography (CTE) for detecting different grade lesions in ileocolonic CD.

METHODS

Forty-one consecutive patients finally diagnosed with ileocolonic CD were included. All the patients prospectively underwent DW-MRE, contrast enhanced CTE, and ileocolonoscopy within 2 weeks. DW-MRE and CTE images were interpreted for the presence or absence of active CD segments by two experienced radiologists independently. Ileocolonic segments (terminal ileum, right colon, transverse colon, left colon, and rectum) were graded as inactive (0-2), mild (3-6), or moderate-severe (≥ 7) by the simplified endoscopic score for CD (SES-CD). Diagnostic efficiencies of DW-MRE and CTE for mild and/or moderate-severe CD segments were calculated and compared, using ileocolonoscopy as reference standard.

RESULTS

According to SES-CD, 190 ileocolonic segments from 41 CD patients were scored as 91 inactive, 68 mild, and 31 moderate-severe CD lesions. The sensitivity of DW-MRE for detecting active from inactive segments was higher than that of CTE, and the specificities of them had no significant differences. As for the subgroup analysis, DW-MRE was more sensitive for mild CD lesions than CTE (76.5% vs 60.3%; P = 0.019), while the sensitivities for moderate-severe CD were similar between these two modalities (96.8% for DW-MRE and 93.5% for CTE; P = 1.00).

CONCLUSIONS

Both DW-MRE and CTE had comparably excellent performances for moderate-severe CD detection; DW-MRE demonstrated better sensitivity in mild lesions compared with CTE and could be more suitable for the diagnosis of mild CD.

ACR Appropriateness Criteria® Crohn Disease

Three common clinical scenarios involving use of imaging in Crohn disease are covered. These include the initial evaluation of Crohn disease when the diagnosis has not been previously established, the evaluation for anticipated exacerbation of known disease, and the evaluation of disease activity during therapy monitoring. The appropriateness of a given imaging modality for each scenario is rated as one of three categories (usually appropriate, may be appropriate, usually not appropriate) to help guide evaluation. Pediatric presentation of Crohn disease and the appropriateness of imaging are not covered in this document. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Usefulness of magnetic resonance enterography in the clinical decision-making process for patients with inflammatory bowel disease

OBJECTIVE

To evaluate the impact of magnetic resonance enterography (MRE) diagnosis on clinical decision-making regarding treatment choice and maintenance of treatment over time in patients with inflammatory bowel disease (IBD).

METHODS

A cohort of patients who underwent MRE for IBD assessment between 2011 and 2014 was analyzed. From clinical records, we retrospectively retrieved their demographic data and clinical data on their IBD at the time of MRE, the results of MRE and the patient's clinical course. Medical management decisions made during the three months following MRE and at the 15-month follow-up were assessed.

RESULTS

In total, 474 MREs were reviewed. In the first three-month period, MRE results led to changes in the medical management of 266 patients (56.1%). Of those, maintenance therapy was altered in 140 patients (68.3%) (90.7% step-up and 9.3% top-down strategy), 65 (24.4%) were prescribed a course of steroids and 61 (22.9%) underwent surgery. MRE confirmed a CD diagnosis in 14/41 patients (34.1%) previously diagnosed with indeterminate colitis or ulcerative colitis and in 4/18 patients (22.2%) with suspected IBD. At the 15-month follow-up, treatment remained unchanged in 289 patients (65.8%).

CONCLUSIONS

These results suggest that MRE is a diagnostic tool that provides valid information for the clinical-decision making process for patients with CD.

Evaluating inflammatory activity in Crohn's disease by cross-sectional imaging techniques

The evaluation of inflammatory bowel activity in patients with Crohn’s disease has traditionally been a challenge, mainly because of the difficulty in gaining endoscopic access to the small bowel. Historically, barium-based contrast studies were the only option for the evaluation of inflammatory activity in Crohn’s disease. They were gradually replaced by cross-sectional imaging techniques, computed tomography enterography (CTE) and magnetic resonance enterography (MRE) now being the modalities of choice for such evaluations. Those two imaging methods have provided important information regarding intestinal wall involvement and extra-intestinal manifestations of Crohn’s disease, not only assessing lesion characteristics and complications but also quantifying inflammatory bowel activity. The objective of this article is to review the main technical aspects of CTE and MRE, together with their indications, contraindications, and limitations, as well as the CTE and MRE imaging characteristics of inflammatory activity in Crohn’s disease.

Safety and effectiveness of MRE in comparison with CTE in diagnosis of adult Crohn's disease

Background: Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract that is characterized by recurrent attacks and frequent recovery. The lifelong course of this disease requires frequent assessment of the disease activity. The aim of this study was to compare the effectiveness and safety of computed tomography enterography (CTE) to magnetic resonance enterography (MRE) in adults with CD.

Methods: A systematic review of the literatures was performed to evaluate the effectiveness and safety of CTE in comparison with MRE. PubMed, Cochrane Library, Scopus, Web of Science, and Embase were searched. Effectiveness outcomes included were sensitivity, specificity, diagnosis difference, diagnostic odds ratio, and positive and negative likelihood. Quality assessment of the studies was conducted using the QADAS score. Meta-analysis was done by RevMan 5.3 for selected outcomes.

Results: Five studies had eligibility for analyzing effectiveness. The meta-analysis results showed that diagnosis difference of MRE and CTE, for diagnosing active CD (0.03 CI 95% -0.07–0.13), fistula (-0.01 CI 95% -0.09–0.07), and cramping (-0.02 CI 95% -0.1– 0.06) were not statistically significant. Six studies were finally selected for safety assessment. The results showed that people who are examined with CTE frequently are at increased risk of developing cancer significantly, as they receive more than 50 msv of radiation per year.

Conclusion: There was no significant difference between MRE and CTE in diagnosis of Crohn’s activity, detection of bowel obstruction, and detection of fistula and stenosis of the alimentary canal. However, the assessment of the safety profile of MRE and CTE showed that MRE is meaningfully safer than CTE for evaluating the recurrence of CD.

Clinical significance of isolated abnormal intestinal findings in magnetic resonance enterography in patients with suspected small bowel disease

PURPOSE

Magnetic resonance imaging (MRE) is a well-established adjunct diagnostic tool for the diagnosis of Crohn's Disease (CD), as ileocolonoscopy can sometimes be falsely reassuring when CD skips distal terminal ileum. We aimed to determine the frequency and clinical significance of isolated abnormal small bowel findings in MRE with normal ileal view in ileoscopy.

METHODS

We retrospectively reviewed findings from 1611 MRE studies that were conducted between 2012 and 2018 to detect patients bearing abnormal intestinal findings and having full ileocolonoscopy. After exclusion of normal or repetitive MRE scans and previously known CD, 147 patients with abnormal MRE detected. MRE scans were categorized as suspicious of CD and non-specific findings.

RESULTS

Out of 147 patients with abnormal MRE, 122 (83%) had terminal ileum involvement in MRE consistent with ileoscopy findings. Twenty-five (17%) patients were found to have solitarily abnormal intestinal findings in MRE with normal ileoscopy. Only 3 (12%) were diagnosed with CD initially, and all had MRE findings suspicious of CD. The remainder 40% (n = 10) were diagnosed with non-Crohn's small bowel disease after further investigation, while in the other 48% (n = 12) abnormal MRE findings could not be explained with any organic disease in the follow-up.

CONCLUSION

The present study demonstrated that only a small portion of patients with isolated abnormal intestinal findings in MRE is CD, and more than that are non-crohn's small bowel diseases. These findings, even if they carry the suspicion of CD, do not transform to CD in the long-term follow-up.

Assessment of the usefulness of imaging studies and biomarkers in the activity of Crohn's disease

Aim

The aim of the study was to determine the suitability of available diagnostic methods, by means of comparison, for predicting disease activity, based on cost efficiency and sensitivity criteria.

Material and methods

In this study, we conducted analyses of 37 patients with Crohn’s disease (CD). CD was graded as “active” or “inactive” by adopting certain cut-off values for every marker. The main assumption was that methods used to grade CD severity do not give false positive results. The authors decided to measure the agreement between the methods by applying Cohen’s κ coefficient.

Results

Endoscopy shows the highest sensitivity, negative predictive value, and accuracy in detecting CD. In the case of both intestines, the sensitivity of endoscopy reached 93.9% and the accuracy 94.6%, while the sensitivity and accuracy of enterography and calprotectin were 51.5% vs. 71,9% and 56.8% vs. 72.2%, respectively. For the large intestine, the sensitivity and accuracy of endoscopy reached 100%. For the small intestine, endoscopy had 55% sensitivity and 75% accuracy, while enterography showed only 66.7% and 81.1%, respectively. The best agreement (77.1%, p = 0.005) was seen between endoscopy and calprotectin for full intestines. However, the value of Cohen’s κ suggests that this agreement is moderate. The optimal cut-off value for calprotectin was 43 µg/g, and the ROC curve (AUC = 0.871) was large enough to conclude that calprotectin is a statistically significant (p < 0.001) indicator of CD activity.

Conclusions

Statistically significant compliance was shown only between colonoscopy and faecal calprotectin.

[Preparation, Technique, and Imaging of Computed Tomography/Magnetic Resonance Enterography]

CT enterography and magnetic resonance (MR) enterography are widely used imaging modalities used to examine the small bowel. These radiologic tests are distinguished from routine abdominopelvic CT and MRI by the oral ingestion of a large amount of neutral contrast to distend the small bowel before scanning. For achievement of high quality, diagnostic images and proper technique are required. Conducted protocols still vary in patient preparation, enteric contrast, and CT and MRI acquisition sequences, resulting in heterogeneous diagnostic accuracy. The purpose of this article is to review the processes and techniques that optimize CT/MR enterography for patients with suspected Crohn's disease or other small bowel diseases.

Impact of therapies on bowel damage in Crohn's disease

Crohn's disease (CD) is a chronic inflammatory bowel disease that usually progresses to bowel damage, defined as strictures, fistulas and abscesses. These complications require intestinal resection and lead to further irreversible structural damage. Cross-sectional imaging, such as magnetic resonance imaging, computed tomography and ultrasound, are accurate in assessing intestinal damage at a definite time point and the progression of damage over time. Recently, an imaging-based index, the Lémann Index, has been proposed and developed in order to quantify bowel damage in CD patients; emerging data confirm that this Index can measure the structural damage with good sensitivity to change. One challenge remains to understand whether existing or future treatments might be able to stop bowel-damage progression or even reverse intestinal damage, improving the prognosis and changing the natural history of CD. We reviewed the current data available in the literature focused on the measure of structural damage in CD patients, mainly focusing on the impact on therapies in reversing bowel damage. We also explored some further perspectives on measuring and targeting intestinal damage in clinical research and in clinical practice as an ultimate therapeutic target.

Pursuing therapeutic success in Crohn’s disease: A matter of definition, tools and longterm outcomes

Management of Crohn’s disease (CD) based on symptom control is a tale of the past as new treatment strategies aim toward a “treat to target” concept and to a patient-tailored approach. Defining treatment goals and assessing therapeutic success have been in the center of IBD research in the past years. Clinical remission and mucosal healing are well-established treatment goals by current recommendations, although prospective data is required to determine whether achieving these targets is enough to alter disease natural course. Furthermore, there is no standard in assessing therapeutic success. Low relapse and hospitalization rates, as well as a low need of surgery are indicators of a successful treatment. Close monitoring is part of the new therapeutic strategy. Monitoring tools are numerous, comprising clinical, biological, endoscopic and imaging scores or parameters but are far from being perfect. The traditional strategy of managing CD patients based on clinical symptoms and response to treatment did not improve the long-term outcomes. Clinical activity scores are frequently used in clinical trials and daily practice, but their use alone is not an accurate measure of inflammation. Endoscopic remission is associated with a lower risk of complications and a better long-term prognostic. Several guidelines include recommendations regarding surveillance endoscopy, but there is an open debate regarding the follow-up intervals. Cross-sectional imaging techniques play a complementary role in assessing transmural inflammation and in identifying extra-intestinal complications of CD and should be used in conjunction with endoscopy. Therapeutic drug monitoring is essential in assessing loss of response and making therapeutic decisions, although firm recommendations are not implemented into daily practice. Extraintestinal manifestations are often disregarded when discussing monitoring protocols. There is no current guideline indication for extraintestinal manifestations monitoring during remission periods.

Noninvasive Multimodal Methods to Differentiate Inflamed vs Fibrotic Strictures in Patients With Crohn's Disease

Fibrotic strictures occur in 30% of patients with Crohn's disease (CD). However, there are no therapeutic agents that prevent or reverse fibrotic strictures. Strictures are treated by endoscopic dilatation procedures and surgical procedures, but there are high rates of recurrence. Two antifibrotic agents (nintedanib and pirfenidone) recently were approved for the treatment of idiopathic pulmonary fibrosis and inhibitors of Rho-associated protein kinases 1 and 2 reversed fibrosis in mice with chronic intestinal inflammation. Cross-sectional imaging techniques, such as magnetic resonance (MR) enterography, computed tomography enterography, and bowel ultrasound, are used to assess small-bowel and CD-related complications, including strictures. It is important to be able to determine the degree of inflammation and fibrosis in strictures to select the best therapy; this can be a challenge because inflammation and fibrosis co-exist to varying degrees in a damaged bowel segment. Delayed gadolinium enhancement, magnetization transfer MR imaging, and ultrasound elastography seem to be promising tools for assessing fibrosis in patients with CD. We review noninvasive techniques for fibrosis assessment, including analyses of genetic, epigenetic, and protein markers. We discuss the potential of imaging techniques such as diffusion-weighted and magnetization transfer MR imaging, strain elastography, shear-wave imaging, and positron emission tomography to guide therapeutic decisions for patients with stricturing CD.

Imaging in discriminating intestinal tuberculosis and Crohn's disease: past, present and the future

Introduction: Intestinal tuberculosis (ITB) and Crohn's disease (CD) have similar clinical presentation, but require different treatment approaches. Despite advances in various endoscopic, imaging, microbiological, and histological techniques, the differentiation of these two entities is often difficult. Newer radiological and image acquisition modalities have now become indispensable tools for evaluation of these two diseases.Areas covered: This review summarizes the currently available literature on various radiological investigations to differentiate ITB from CD. This review also enumerates the newer modalities in image acquisition techniques and their potential role for differentiating these two diseases. At present abdominal computed tomography (CT) scan is used as a first line investigation for differentiating ITB from CD. Magnetic resonance imaging (MRI) is preferred in pediatric patients and for follow-up studies.Expert opinion: Role of newer modalities like contrast enhanced abdominal ultrasound, perfusion CT, advanced MRI and positron emission tomography (PET) is evolving and requires further exploration. Till further robust studies are available, differentiation between ITB and CD requires use of a combination of clinical, endoscopic, serological, histological, and radiological parameters rather than relying on a single test.

Indian guidelines on imaging of the small intestine in Crohn's disease: A joint Indian Society of Gastroenterology and Indian Radiology and Imaging Association consensus statement

The Indian Society of Gastroenterology (ISG) Task Force on Inflammatory Bowel Disease and the Indian Radiological and Imaging Association (IRIA) developed combined ISG-IRIA evidence-based best-practice guidelines for imaging of the small intestine in patients suspected to have or having Crohn's disease. The 29 consensus statements, developed through a modified Delphi process, are intended to serve as reference for teaching, clinical practice, and research.

Development and Validation of a Simplified Magnetic Resonance Index of Activity for Crohn's Disease

BACKGROUND & AIMS

The magnetic resonance index of activity (MARIA) for Crohn's disease (CD) is used to assess the activity of luminal CD. However, it has a number of practical limitations. We aimed to develop and validate a simplified MARIA to more easily and quickly assess CD activity and response to therapy.

PATIENTS AND METHODS

We performed a retrospective analysis of magnetic resonance imaging data from 98 participants in 2 studies. We used logistic regression analysis to identify magnetic resonance imaging parameters independently associated with CD endoscopic index of severity (CDEIS) scores (the reference standard). We validated the responsiveness and reliability of the simplified MARIA in an independent cohort of 37 patients who underwent magnetic resonance imaging and endoscopy before and after a therapeutic intervention.

RESULTS

Logistic regression analysis showed that dichotomous qualitative assessment of wall thickening (>3 mm), presence of mural edema, perienteric fat stranding, and ulcers were independently associated with CDEIS scores; we used these factors to create a simplified MARIA. Simplified MARIA scores greater than 1 identified segments with active CD with 90% sensitivity and 81% specificity (area under the curve 0.91; 95% confidence interval 0.88-0.94). Simplified MARIA scores of 2 or more detected severe lesions (ulcers) with 85% sensitivity and 92% specificity (area under the curve 0.94; 95% confidence interval 0.91-0.96). For each patient, there was a high level of correlation between simplified MARIA scores and CDEIS scores (r = 0.83) and simplified MARIA scores and original MARIA scores (and r = 0.93) (P < .001). The simplified MARIA score accurately detected changes in lesion severity in response to therapy and was as reliable as endoscopy for the assessment of mucosal healing.

CONCLUSION

We developed and validated a simplified MARIA for easier and faster assessment of CD activity and severity. This index identifies patients with a response to therapy with a high level of accuracy. These findings require confirmation in independent, multireader studies.

Surgical Management of Complex Enteric Fistulas in Crohn's Disease

Crohn's disease is a chronic, inflammatory bowel condition that can affect the entire digestive tract and in many cases lead to enteric fistula formation. The management of enteric fistulas can be challenging and often requires a multidisciplinary approach.

Magnetic resonance enterography features of small bowel Crohn's disease activity: an inter-rater reliability study of small bowel active inflammation in clinical practice setting

OBJECTIVE

The aim of this study is to determine the interrater agreement in a clinical practice environment for the most commonly used magnetic resonance enterography (MRE) features of Crohn's disease (CD).

METHODS

CD patients with MRE's before and after treatment were retrospectively identified using search queries over a 7-year period (May 2017-September 2017). MRE features of CD comprising components of multiple CD scoring indices were scored by radiologists in the same segment of bowel. Agreement for nominal categorical and continuous variables was assessed using a κ and interclass correlation coefficients, respectively.

RESULTS

80 scans comprised the study population. Moderate interrater agreement was seen in both the pre- and post-treatment MRE's for presence of diffusion restriction (к = 0.43, 0.48; pre- and post-treatment), stricturing disease (к = 0.51, 0.52), overall degree of severity (к = 0.49, 0.59). Substantial agreement was seen in pre- and post-treatment scans for length of involvement (interclass correlation coefficient = 0.67, 0.61). The presence of mucosal ulceration had no agreement (к = -0.07, -0.042).

CONCLUSION

Many MRE features of active CD comprising the major CD scoring indices are reproducible when interpreted by non-CD focused abdominal radiologists. However, the presence of mucosal ulcerations had no agreement and may need more investigation before including this feature as a driver in therapeutic decision making.

ADVANCES IN KNOWLEDGE

Demonstrates the unreliability of mucosal ulceration by non-CD focused abdominal radiologists, targeting a potential area for future education. Key Points The majority of MRE findings incorporated in to many CD scoring indices have fair to moderate inter-rater agreement even when read by non-MRE expert radiologists. Substantial agreement was seen in the length of involved bowel, but this feature is only incorporated in to one of the CD scoring indices. Presence of mucosal ulcerations had no interrater agreement in our study-a feature which is heavily weighted by several CD scoring indices. Research should be focused bridging those features which have poor interrater agreement.

"Can Magnetic Resonance Enterography (MRE) replace ileo-colonoscopy for evaluating disease activity in Crohn's disease?"

Crohn's disease is a form of chronic inflammatory bowel disease that can lead to structural bowel damage due to transmural inflammation. Ileo-colonosocopy is currently essential for initial diagnosis. Reassessment of disease burden is frequently needed during episodes of active disease and when evaluating treatment efficacy. This review compares the role of Magnetic Resonance Enterography (MRE) and ileocolonoscopy in Crohn's disease management and whether cross-sectional imaging can replace invasive endoscopic tests. MRE can give information on the small bowel not visible at ileo-colonoscopy, and on extra-luminal complications. Evaluation of the bowel by MRE allows assessment of the submucosa and serosa, and thus transmural healing. MRE offers a well tolerated investigation and additional information on disease activity to better manage patients with Crohn's disease. Increasingly, there are a range of newer techniques such as diffusion weighted imaging, magnetisation transfer and motility MRI which provide greater information on fibrosis and predictors to treatment response which has been lacking despite the use of ileo-colonoscopy for several decades.

Utility of MR Imaging in Abdominopelvic Emergencies

Acute abdominopelvic pain, a common symptom in emergency department patients, is challenging given the spectrum of differential diagnoses encompassing multiple organ systems, ranging from benign self-limiting to life-threatening and emergent. Diagnostic imaging is critical given its high accuracy and management guidance. A contrast-enhanced computed tomography (CT) scan is preferred given its widespread availability and speed of acquisition. MR imaging may be appropriate, usually performed for specific indications with tailored protocols. It is accurate for diagnosis and may be an alternative to CT. This article discusses the advantages and disadvantages, protocols, and appearances of MR imaging of common diagnoses.

The role of small bowel endoscopy for Crohn's disease

PURPOSE OF REVIEW

The review discusses the roles of small bowel capsule endoscopy and deep enteroscopy in patients with Crohn's disease. It highlights recent advances in the field and identifies areas where evidence is lacking.

RECENT FINDINGS

Small bowel capsule endoscopy has an important role in the follow-up of patients with Crohn's disease after escalation of therapy and in the postoperative assessment period following surgical resection. Device-assisted enteroscopy offers the therapeutic advantage of small bowel dilatation, which may result in a reduction in the number of surgical resections required, thus avoiding long-term complications, such as short bowel syndrome and malabsorption.

SUMMARY

Capsule endoscopy has an established role in the diagnosis and management of small bowel Crohn's disease. It is used in the setting of suspected Crohn's disease when ileocolonoscopy is negative and for the assessment of extent of small bowel disease in established Crohn's disease. It is relatively well tolerated because of the provision of patency capsule endoscopy to minimize the risk of inadvertent capsule retention. Device-assisted enteroscopy aids with the diagnosis of Crohn's disease as it enables histology to be taken from inflamed areas within the small bowel. Therapeutic procedures can be carried out during device-assisted enteroscopy including dilatation of Crohn's disease-related strictures and retrieval of retained capsules.

Intra-Cavitary Contrast-Enhanced Ultrasound: A Novel Radiation-Free Method for Detecting Abscess-Associated Penetrating Disease in Crohn's Disease

BACKGROUND AND AIM

Penetrating disease is a common condition complicating Crohn's disease [CD]. Establishing the presence of a fistula and the anatomical definition of the fistulous tracts are essential for deciding on appropriate treatment strategies. We aimed to assess the diagnostic accuracy of intra-cavitary contrast-enhanced ultrasound [IC-CEUS] for the detection of a fistulous tract associated with abscesses in CD patients.

METHODS

In this prospective cohort study, consecutive CD patients suspected of having an intra-abdominal abscess, who were referred for US-guided aspiration were recruited. IC-CEUS was performed by injecting diluted contrast agent [SonoVue] into the abscess cavity immediately following the ultrasound-guided needle abscess aspiration and drainage. The diagnostic accuracy of IC-CEUS in demonstrating the presence of fistulous tracts was compared with that of computed tomography enterography/magnetic resonance enterography [CTE/MRE], using surgical and gross pathological findings as the reference standard.

RESULTS

Thirty-one patients who underwent IC-CEUS and subsequent surgery were included in the final analysis. IC-CEUS demonstrated fistulous/sinus tracts in 26 of 31 participants with a sensitivity and specificity of 86.7 % (95% confidence interval [CI], 68.4-95.6%) and 100% [95% CI, 5.5-100.0%], respectively. Moreover, IC-CEUS correctly demonstrated fistulous/sinus tracts in 13 participants without delineation of fistulous/sinus tracts on CTE/MRE. Combining IC-CEUS and CTE/MRE, the fistula/sinus tract was clearly demonstrated in 29 patients [93.5%, 29/31]. The mean duration of the IC-CEUS procedure was 8.6 min [range 5.0-12.0]. No severe adverse events occurred during the IC-CEUS procedure.

CONCLUSION

In this pilot study, IC-CEUS accurately delineated the anatomical definition of fistulous/sinus tracts associated with intra-abdominal abscesses in CD patients. As a radiation-free and safe technique, IC-CEUS may be used as an alternative/adjunctive method to CTE/MRE for detecting penetrating disease in patients with CD.

Creeping Fat Assessed by Small Bowel MRI Is Linked to Bowel Damage and Abdominal Surgery in Crohn's Disease

BACKGROUND

Crohn's disease (CD) leads to bowel damage and surgery in a significant proportion of patients.

AIMS

The aim of the study was to evaluate the predictive value of creeping fat assessed by small bowel MRI in CD patients.

METHODS

CD patients undergoing small bowel MRI were included in a retrospective observational cohort study. Clinical findings were extracted and correlated with radiological outcome measures. Logistic regression analysis was performed to assess predictors associated with a complicated course and surgery within 2 years and long-term follow-up.

RESULTS

Ninety patients (49% female, median follow-up 93 months) were included. Creeping fat was identified in 21.1%. Of these patients, 68% and 79% developed bowel damage (p < .05) and 42% and 63% of patients revealing creeping fat underwent surgery within 2 years following MRI and total follow-up, respectively. The presence of creeping fat [odds ratio (OR) 4.0], inflammatory stenosis (OR 3.7), multisegmental (small) bowel (OR 4.5 and 3.8), and proximal small bowel inflammation (OR 5.0) were associated with inferior outcome (p < .05) in a univariate analysis. Creeping fat was independently associated with a disabling course, bowel damage, and surgery (OR 3.5 each, p < .05) in a multivariate analysis model.

CONCLUSION

Creeping fat identified by small bowel MRI is associated with a complicated course and abdominal surgery in CD. Our data adds evidence that small bowel MRI facilitates risk stratification in order to define a patient at risk of disease-related complications in CD. [DRKS00011727, www.germanctr.de/ ].

Magnetic resonance enterography predicts the prognosis of Crohn's disease

Background/Aims

Magnetic resonance enterography (MRE) has emerged as an important tool in the diagnosis and follow-up of Crohn's disease (CD). The aim of this study was to evaluate whether MRE findings could predict the prognosis of CD.

Methods

In this retrospective study, a total of 173 patients with clinical remission of CD (n=61) or active CD (n=112) were identified. The outcomes of clinical relapse, admission, surgery, and need for other medications according to the MRE findings were evaluated.

Results

The presence of active inflammation on MRE was observed in 93 (83%) patients with clinically active CD and in 44 (72.1%) patients with clinical remission of CD, without a statistically significant difference (P=0.091). In multivariate analysis, active inflammation on MRE increased the risk for clinical relapse (hazard ratio [HR], 6.985; 95% confidence interval [CI], 1.024–47.649) in patients with clinical remission of CD. In patients with clinically active CD, active inflammation on MRE increased the risk for CD-related hospitalization (HR, 2.970; 95% CI, 1.006–8.772).

Conclusions

The presence of active inflammation on MRE was significantly associated with poor prognosis both in patients with clinical remission of CD and in those with active CD.