Detection of Crohn disease lesions of the small and large bowel in pediatric patients: diagnostic value of MR enterography versus reference examinations. AJR Am J Roentgenol. 2014;203:W533-W542. [PMID: 25341168 DOI: 10.2214/ajr.13.11792]

Magnetic Resonance Imaging of the Gastrointestinal Tract: Current Role, Recent Advancements and Future Prospectives

This review focuses on the role of magnetic resonance imaging (MRI) in the evaluation of the gastrointestinal tract (GI MRI), analyzing the major technical advances achieved in this field, such as diffusion-weighted imaging, molecular imaging, motility studies, and artificial intelligence. Today, MRI performed with the more advanced imaging techniques allows accurate assessment of many bowel diseases, particularly inflammatory bowel disease and rectal cancer; in most of these diseases, MRI is invaluable for diagnosis, staging, and disease monitoring under treatment. Several MRI parameters are currently considered activity biomarkers for inflammation and neoplastic disease. Furthermore, in younger patients with acute or chronic GI disease, MRI can be safely used for short-term follow-up studies in many critical clinical situations because it is radiation-free. MRI assessment of functional gastro-esophageal and small bowel disorders is still in its infancy but very promising, while it is well established and widely used for dynamic assessment of anorectal and pelvic floor dysfunction; MRI motility biomarkers have also been described. There are still some limitations to GI MRI related to high cost and limited accessibility. However, technical advances are expected, such as faster sequences, more specific intestinal contrast agents, AI analysis of MRI data, and possibly increased accessibility to GI MRI studies. Clinical interest in the evaluation of bowel disease using MRI is already very high, but is expected to increase significantly in the coming years.

Comparison of Diagnostic Performance of Ultrasonography and Magnetic Resonance Enterography in the Assessment of Active Bowel Lesions in Patients with Crohn’s Disease: A Systematic Review and Meta-Analysis

We aimed to evaluate and compare the diagnostic performances of ultrasonography (US) and magnetic resonance enterography (MRE) in assessing active bowel lesions in patients with Crohn’s disease (CD). Materials and Methods: We searched PubMed and EMBASE for studies in which US and MRE were used to assess active bowel lesions in CD patients. Bivariate random effect meta-analytic methods were used to estimate pooled sensitivity, specificity, and hierarchical summary receiver operating characteristic (HSROC) curves. We performed a meta-regression analysis to explore the source of study heterogeneity. Results: Eleven studies involving 752 patients were included. US exhibited a pooled sensitivity of 86% (95% confidence interval (CI) 72–94), pooled specificity of 88% (95% CI 78–94), and HSROC of 0.93 in 10 studies. MRE exhibited a pooled sensitivity of 88% (95% CI 76–95), pooled specificity of 87% (95% CI 73–95), and an HSROC of 0.94 in eight studies. In seven studies comparing the diagnostic performances of US and MRE, the summary sensitivity of US and MRE were 86% (95% CI 65–96, I² = 92.1) and 86% (95% CI 72–93, I² = 88.1) (p = 0.841), respectively. The summary specificity of US and MRE were 87% (95% CI 78–93, I² = 79.8%) and 84% (72–90, I² = 72.5%) (p = 0.431), respectively, which showed no statistical differences. On meta-regression analysis, studies from Europe (p = 0.002), those that used linear US probes (p = 0.012), those on small bowel lesions (p = 0.01), and those with outcomes as combined features (active inflammation) reported higher US sensitivity than those from other regions, those that used both linear and convex US probes, those on small and large bowels, and those with outcome as one feature (bowel wall thickening or ulcer). Studies with pediatric patients (p = 0.001), those with reference standards including US (p = 0.001), and outcomes as combined features (p = 0.01) reported higher MRE specificity than those with adult populations, reference standards other than the US, and outcomes as one feature. Conclusions: In spite of considerable heterogeneity in the included studies, both US and MRE can diagnose active bowel lesions with comparable diagnostic accuracy in patients with CD. The study region, type of US probe, lesion location, investigated outcome for US sensitivity and study population, reference standards, and investigated outcomes for MRE specificity were potential sources of heterogeneity.

ACR Appropriateness Criteria® Crohn Disease-Child

Crohn disease is an inflammatory condition of the gastrointestinal tract with episodes of exacerbation and remission occurring in children, adolescents, and adults. Crohn disease diagnosis and treatment depend upon a combination of clinical, laboratory, endoscopic, histological, and imaging findings. Appropriate use of imaging provides critical information in the settings of diagnosis, assessment of acute symptoms, disease surveillance, and therapy monitoring. Four variants are discussed. The first variant discusses the initial imaging for suspected Crohn disease before established diagnosis. The second variant pertains to appropriateness of imaging modalities during suspected acute exacerbation. The third variant is a substantial discussion of recommendations related to disease surveillance and monitoring of Crohn disease. Finally, panel recommendations and discussion of perianal fistulizing disease imaging completes the 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.

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.

Diagnostic Accuracy of Non-Invasive Imaging for Detection of Colonic Inflammation in Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Endoscopy is the gold standard for objective assessment of colonic disease activity in inflammatory bowel disease (IBD). Non-invasive colonic imaging using bowel ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) may have a role in quantifying colonic disease activity. We reviewed the diagnostic accuracy of these modalities for assessment of endoscopically or histopathologically defined colonic disease activity in IBD. We searched Embase, MEDLINE, and the Web of Science from inception to 20 September 2021. QUADAS-2 was used to evaluate the studies' quality. A meta-analysis was performed using a bivariate model approach separately for MRI and US studies only, and summary receiver operating characteristic (ROC) curves were obtained. CT studies were excluded due to the absence of diagnostic test data. Thirty-seven studies were included. The mean sensitivity and specificity for MRI studies was 0.75 and 0.91, respectively, while for US studies it was 0.82 and 0.90, respectively. The area under the ROC curves (AUC) was 0.88 (95% CI, 0.82 to 0.93) for MRI, and 0.90 (95% CI, 0.75 to 1.00) for US. Both MRI and US show high diagnostic accuracy in the assessment of colonic disease activity in IBD patients.

Usefulness of Colon Assessment by Magnetic Resonance Enterography in Pediatric Patients with Inflammatory Bowel Disease-Retrospective Case Series

Background: Magnetic resonance enterography (MRE) is an excellent way to study the small bowels. During such an examination, the colon is also seen within the field of study. The aim of this study was to evaluate the effectiveness of MRE in detecting characteristics of active inflammatory bowel disease (IBD) in the colon, in comparison to different features seen in colonoscopies. Methods: This retrospective study was conducted with 41 children. Features of active inflammation we considered were wall thickening; contrast enhancement; incorrect signal in the DWI sequence in the MRE; and presence of ulceration, erosion, erythema, spontaneous bleeding and a decrease of the vascular pattern seen in colonoscopy. The colon was divided into six segments: caecum, ascending, transverse, descending, sigmoid and rectum. Results: The sensitivity of MRE was, on average, 50–75%, and as high as 92–100%, depending on the segment. The most important feature for which there was the most dependencies was ulceration. In the analysis of intestinal wall thickness, the AUC value >0.8 was detected as ulceration (segments: cecum, ascending, descending colon, sigmoid), spontaneous bleeding (ascending colon and sigmoid) and decreased vascular pattern (ascending, transverse, descending colon). Conclusions: Evaluation of qualitative structural changes in MRE distinguishes patients with inflammation in colonoscopy from patients without lesions, with high diagnostic accuracy, albeit higher specificity than sensitivity.

MR enterography grading of pediatric ileocolonic Crohn disease activity based on a single bowel segment

BACKGROUND

Ileocolonoscopy with histology has been considered the gold standard for Crohn disease (CD) diagnosis and monitoring. Over the last years, magnetic resonance enterography (MRE) has become more and more popular, representing a valid non-invasive technique.

OBJECTIVE

To propose a simplified MRE score, the pediatric CD magnetic resonance index (PCDMRI), based only on the most affected bowel segment, to grade active inflammation in children with CD.

MATERIALS AND METHODS

Two radiologists retrospectively evaluated MRE images of children with histopathology-proven CD. The PCDMRI was based on six mural and perimural variables assessed for the most affected bowel segment (chosen by visual inspection of the key bowel wall imaging findings associated with active inflammation), and five extramural per-examination features. Correlation analysis was performed between both the PCDMRI and the MRE global score (based on all the affected segments) and the pediatric clinical disease activity index (PCDAI), the simple endoscopic score for CD (SES-CD), serum C-reactive protein (CRP) and fecal calprotectin (fC). Inter-reader reproducibility of the scoring system was estimated. Agreement on disease location between MRE and ileocolonoscopy was evaluated.

RESULTS

The study involved 42 children for a total of 80 MRE. PCDMRI and global score positively correlated with PCDAI, SES-CD, CRP and fC. Inter-reader reproducibility was 91%. Agreement on disease location was substantial.

CONCLUSION

The PCDMRI and the global score resulted equally correlated with the PCDAI, suggesting a high impact of the most affected segment on symptoms. The PDCMRI may be a useful non-invasive tool for a rapid and reproducible grading of the disease activity in children with ileocolonic CD.

Diagnostic performance of magnetic resonance enterography and ultrasound in children with inflammatory bowel diseases: a diagnostic test accuracy meta-analysis

OBJECTIVES

Magnetic resonance enterography (MRE) and ultrasound (US) can be used to diagnose inflammatory bowel diseases (IBD) in children. This meta-analysis aimed to determine the diagnostic performance of MRE and US in pediatric patients with IBD.

METHODS

PubMed, Embase, and the Cochrane Library were searched for eligible studies published up to June 1, 2020. The outcomes were the performances of MRE and US at the segment and patient levels. Pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR), diagnostic odds ratio (DOR), and the area under the summary receiver operating characteristic curves value (SROC) were analyzed.

RESULTS

Eight studies (340 children) were included. Compared with the reference standard, MRE showed pooled sensitivity of 93.0% (95% confidence interval (CI): 90.0-95.4%), specificity of 94.6% (95% CI: 92.1-96.5%), PLR of 11.146 (95% CI: 5.027-24.713), NLR of 0.094 (95% CI: 0.057-0.155), and DOR of 134.21 (95% CI: 40.72-442.29), with a SROC of 0.9721. Similar results were observed at the patient and segment levels. Compared with the reference standard, US had pooled sensitivity of 84.1% (95% CI: 69.9-93.4%), specificity of 82.9% (95% CI: 66.4-93.4%), PLR of 4.924 (95% CI: 2.351-10.310), NLR of 0.207 (95% CI: 0.103-0.413), and DOR of 25.919 (95% CI: 7.63-88.07), but only two studies were included. US (reader 1) had a similar diagnostic value to US (reader 2).

CONCLUSIONS

The present meta-analysis shows that MRE has good performance in detecting IBD in pediatric patients. Only two studies used US, and additional studies are necessary to confirm the diagnostic performance of US for IBD in children.

KEY POINTS

• MRE has good performance in the detection of IBD in pediatric patients. • Similar results were observed at the patient and segment levels for MRE. • Only two studies were included for US, without differentiating patient/segment.

Value of magnetic resonance enterography in diagnosis and treatment follow up in Crohn's disease in children

PURPOSE

Crohn's disease (CD) is a chronic inflammatory disease which can affect all parts of the gastrointestinal tract. Magnetic resonance enterography (MRE) enables detection of pathologic changes in the small intestine, which are not accessible by conventional endoscopy. The aim of the study was to assess the value of MRE in imaging of small bowel lesions, their location and extent, in CD patients and its correlation with clinical and endoscopic activity.

MATERIALS AND METHODS

MRE was performed in 108 children with CD, aged 5.5 to 18 years. The diagnosis was based on the Porto criteria. Location and clinical manifestation was evaluated according to the Paris classification. Clinical CD activity was assessed with PCDAI and endoscopic activity with SES-CD. In 36 children, control MRE was performed.

RESULTS

The most common endoscopic location of the disease was the colon (41.7%), terminal ileum and colon (24.1%). Inflammation as the main clinical manifestation was dominant (81.5%). In MRE, inflammatory changes were found in 40.8% of children, strictures in 11.1%. The EIA value (activity in MRE) increased along with PCDAI score and SES-CD. MRE performed during follow up, showed transmural healing in 16.7% of patients and improvement in 55.5%.

CONCLUSIONS

MRE is an efficient diagnostic tool in proper characterization of disease location in pediatric CD. As positive correlation of the results of MRE with the endoscopic and clinical activity has been found, taking into account good tolerance and non-invasiveness of the procedure it can be recommended to be used in reassessment.

Capsule Endoscopy Complements Magnetic Resonance Enterography and Endoscopy in Evaluating Small Bowel Crohn's Disease

Aims

Wireless capsule endoscopy (WCE) and magnetic resonance enterography (MRE) are increasingly utilized to evaluate the small bowel (SB) in Crohn's disease (CD). The primary aims were to compare the ability of WCE and MRE to detect SB inflammation in children with newly diagnosed CD, and in the terminal ileum (TI) to compare them to ileo-colonoscopy. Secondary aims were to compare diagnostic accuracy of WCE and MRE and changes in Paris classification after each study.

Methods

Patients (10 to 17 years of age) requiring ileo-colonoscopy for suspected CD were invited to participate. Only patients with endoscopic/histologic evidence of CD underwent MRE and WCE. SB inflammation and extent were documented and comparative analyses performed.

Results

Of 38 initially recruited subjects, 20 completed the study. WCE and MRE were similarly sensitive in identifying active TI inflammation (16 [80%] versus 12 [60%]) and any SB inflammation (17 [85%] versus 16 [80%]). However, WCE detected more extensive SB disease than MRE with active inflammation throughout the SB in 15 [75%] versus 1 [5%] patient (P < 0.001). Moreover, WCE was more likely to detect proximal SB disease (jejunum and ileum) compared to MRE (85% versus 50%, P = 0.04). Overall, the Paris classification changed in 65% and 85% of patients following MRE and WCE, respectively.

Conclusions

WCE is as sensitive as MRE for identifying active TI inflammation, but appears more sensitive in identifying more proximal SB inflammation. In the absence of concern regarding stricturing or extra-luminal disease WCE can be considered for the evaluation of suspected SB CD.

Assessment of Bowel Inflammation and Strictures by Magnetic Resonance Enterography in Long-term Crohn's Disease

BACKGROUND

Crohns disease [CD] is a chronic inflammation in the gut that often progresses to fibrosis. Magnetic resonance enterography [MRE] is an important diagnostic tool in evaluating CD. We aimed to assess the prevalence of inflammation and stricturing disease in patients with long-term CD, and to investigate associations with clinical factors.

METHODS

We performed a follow-up analysis of a population-based cohort of 237 CD patients in south-eastern Norway 20 years after diagnosis; 95 patients were examined with MRE, and the magnetic enterographic global score [MEGS] was calculated. We assessed inflammation and strictures during the follow-up. Association of the MEGS and bowel strictures with clinical variables was examined by univariate regression analysis.

RESULTS

Of the 237 patients, 62 [65.3%] had active inflammation mostly affecting the terminal ileum; 35 [36.8%] had substantial inflammation according to MEGS, which associated with inflammatory biomarkers during the follow-up; and 25 [26.3%] had stricturing disease that associated with age (odds ratio [OR] = 0.92), initial use of systemic steroids [OR = 3.36], and inflammatory biomarkers. Most patients with strictures were treated with surgery without recurrence [n = 24, 42.1%] and seven [21.2%] strictures in the terminal ileum healed without surgery.

CONCLUSIONS

Twenty years after the diagnosis, the majority of patients had active inflammation, often complicated by stricturing disease. Most patients with strictures were treated with surgery without recurrence, and some strictures resolved over time. Inflammatory biomarkers, extensive and complicated disease type, and use of systemic medication associated with both inflammation and stricturing disease.

Magnetic resonance enterography (MRE) and ultrasonography (US) in the study of the small bowel in Crohn's disease: state of the art and review of the literature

Crohn’s disease (CD) is a chronic idiopathic disease and its diagnosis is based on a combination of clinical symptoms, laboratory tests and imaging data. There isn’t a diagnostic gold standard: the ileocolonoscopy with mucosal biopsies represents the standard for luminal disease, while cross-sectional imaging such as Ultrasound (US), Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) can show transmural alterations and extraintestinal manifestations. CD is usually diagnosed in the young age and after baseline diagnosis, the patients have to undergo to variable follow-up depending on remission or active disease. The aim of our review is to compare Magnetic Resonance Enterography (MRE) to Ultrasonography (US) in the follow-up of CD. (www.actabiomedica.it)

MRI reveals different Crohn's disease phenotypes in children and adults

OBJECTIVES

To identify differences between two cohorts of adult and pediatric patients affected by Crohn's disease (CD), with regard to lesion location in the small intestine and colon-rectum, lesion activity, and prevalence of perianal disease (PD), using MRI as the main diagnostic tool.

METHODS

We retrospectively reviewed 350 consecutive MRI examinations performed between 2013 and 2016 in outpatients or inpatients with histologically proven CD, monitored by the Gastroenterology and Pediatric Units of our Hospital. The magnetic resonance enterography (MRE) protocol for adult and pediatric CD patients routinely includes evaluation of nine different intestinal segments (from jejunum to rectum) and of the anal canal. Intestinal activity was also calculated using a validated score. Perianal disease (PD) was staged. Fisher's exact test was used and the odds ratio (OR) was calculated.

RESULTS

Two hundred and nineteen out of 350 MRI studies (118 adults and 101 children) were included. The prevalence of PD was 34.6% in children and 16.1% in adults (OR = 2.8; p = 0.0017). Pediatric patients showed more frequent rectal involvement (29.7% vs 13.5%, OR = 2.7; p = 0.0045) and higher risk of PD in the presence of rectal disease (p = 0.043; OR = 4.5). In pediatric patients with severe colorectal disease, the prevalence of PD was twofold (86.7% vs 40%; p = 0.072). Using the clinical Montreal classification for lesion location, no significant differences emerged between the two patient populations.

CONCLUSIONS

MRI showed a significantly higher prevalence of rectal involvement and perianal disease in the pediatric population. These results may have a relevant clinical impact and deserve further investigation.

KEY POINTS

• To our knowledge, this is the largest morphological comparative study available in the literature using MRI as the main diagnostic tool to compare adult patients and children with Crohn's disease. • Our study showed significant differences between adults and children: a higher prevalence of rectal and perianal fistulous disease (PD) in pediatric patients and an increased prevalence of PD in the presence of severe colon-rectum involvement. • The association of rectal and perianal disease implies a poorer clinical prognosis and a higher risk of disabling complications in pediatric patients.

Can diffusion weighting replace gadolinium enhancement in magnetic resonance enterography for inflammatory bowel disease in children?

BACKGROUND

Contrast-enhanced MRI is often used for diagnosis and follow-up of children with inflammatory bowel disease.

OBJECTIVE

To compare the accuracy of diffusion-weighted MRI (DWI) to contrast-enhanced MRI in children with known or suspected inflammatory bowel disease.

MATERIALS AND METHODS

This retrospective, consecutive study included 55 children. We used ileo-colonoscopy and histology as the reference standard from the terminal ileum to the rectum, and contrast-enhanced MRI as the reference standard proximal to the terminal ileum. DWI and contrast-enhanced MRI sequences were independently reviewed and compared per patient and per segment to these reference standards and to the follow-up for each child.

RESULTS

We obtained endoscopic data for 340/385 colonic and ileal segments (88%). The rate of agreement per segment between DWI and endoscopy was 64%, and the rate of agreement between contrast-enhanced MRI and endoscopy was 59%. Per patient, sensitivity and specificity of bowel wall abnormalities as compared to the endoscopy were 87% and 100% for DWI, and 70% and 100% for contrast-enhanced MRI, respectively. Positive and negative predictive values were, respectively, 100% and 57% for DWI, and 96% and 41% for contrast-enhanced MRI. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of DWI compare to contrast-enhanced MRI in the segments proximal to the terminal ileum were 90%, 98%, 90%, 98% and 96%, respectively.

CONCLUSION

The diagnostic performance of DWI is competitive to that of contrast-enhanced MRI in children with known or suspected inflammatory bowel disease.

Magnetic resonance enterography evaluation of Crohn disease activity and mucosal healing in young patients

MR enterography (MRE) has become the primary imaging modality for assessing Crohn disease in young patients because of its lack of ionizing radiation, superior soft-tissue contrast, and cross-sectional capability to evaluate disease activity as well as extraluminal and extra-intestinal complications. MRE has been extensively validated against both histological and endoscopic references as a noninvasive imaging biomarker of Crohn disease activity. More recent studies have also validated MRE as a noninvasive biomarker of mucosal healing, an important endpoint of Crohn disease therapy. In this review, we summarize the current evidence supporting the use of MRE features as imaging biomarkers of Crohn disease activity and treatment response.

Diagnostic Performance of Magnetic Resonance Enterography for Detection of Active Inflammation in Children and Adolescents With Inflammatory Bowel Disease: A Systematic Review and Diagnostic Meta-analysis

Importance

Magnetic resonance (MR) enterography has the advantage over other techniques of being noninvasive, lacking ionizing radiation, and demonstrating excellent soft-tissue contrast to evaluate pediatric patients with inflammatory bowel disease (IBD).

Objective

To evaluate the diagnostic performance of MR enterography for detection of active inflammation in children and adolescents with known or suspected IBD.

Data Sources

A search of MEDLINE and EMBASE up to January 2, 2017, was performed to identify studies. Search terms included child, pediatric, adolescent, Crohn disease, inflammatory bowel disease, and magnetic resonance enterography. The search was limited to English-language publications.

Study Selection

Studies evaluating the diagnostic performance of MR enterography for detection of active inflammation in pediatric patients with known or suspected IBD were selected. Two reviewers independently assessed the eligibility of the selected articles.

Data Extraction and Synthesis

The study was performed and reported in accordance with the PRISMA guidelines. Pooled summary estimates of sensitivity and specificity were calculated using hierarchical logistic regression modeling.

Main Outcomes and Measures

The diagnostic performance of MR enterography for detection of active inflammation in pediatric patients with known or suspected IBD was the primary outcome. Subgroup analyses and meta-regression were performed.

Results

Eighteen original articles involving a total of 687 patients were included. The summary sensitivity was 83% (95% CI, 75%-89%), the summary specificity was 93% (95% CI, 90%-95%), and the area under the hierarchical summary receiver operating characteristic curve was 0.95 (95% CI, 0.93-0.97). The Higgins I2 statistics demonstrated substantial heterogeneity in terms of sensitivity (I2 = 84.1%) and specificity (I2 = 68.8%). Based on per-patient analysis, the summary sensitivity was 86% (95% CI, 78%-91%) and specificity was 91% (95% CI, 82%-96%). In meta-regression, among the various potential covariates, scanner manufacturer was associated with study heterogeneity.

Conclusions and Relevance

Magnetic resonance enterography, which is a noninvasive, radiation-free modality, demonstrates high diagnostic performance in the diagnosis of active inflammation in pediatric patients with IBD, especially at the per-patient level.

Diagnostic yield of capsule endoscopy versus magnetic resonance enterography and small bowel contrast ultrasound in the evaluation of small bowel Crohn's disease: Systematic review and meta-analysis

BACKGROUND AND AIMS

Capsule endoscopy (CE), magnetic resonance enterography (MRE) and small bowel (SB) intestinal contrast ultrasound (SICUS) are the modalities of choice for SB evaluation. This study aimed to compare the diagnostic yield (DY) of CE to MRE and SICUS in detection and monitoring of SB CD through meta-analysis of the available literature.

METHODS

We performed a systematic literature search for trials comparing the accuracy of CE, MRE and SICUS for detection of active SB inflammation in patients with suspected and/or established CD. Only prospective studies comparing CE with another additional diagnostic modality were included in the final analysis. Pooled odds ratios (ORs) for the DY of the three modalities were calculated.

RESULTS

A total of 112 studies were retrieved; following selection, 13 studies were eligible for analysis. The DY of CE for detection of active SB CD was similar to that of MRE (10 studies, 400 patients, OR 1.17; 95% CI 0.83-1.67) and SICUS (5 studies, 142 patients, OR 0.88; 95% CI 0.51-1.53). The outcomes were similar for the subgroups of suspected versus established CD and adult versus pediatric patients. CE was superior to MRE for proximal SB CD (7 studies, 251 patients, OR 2.79; 95% CI 1.2-6.48); the difference vs SICUS was not significant.

CONCLUSION

CE, MRE and SICUS have similar DY for detection of SB CD in both suspected and established CD. CE is superior to MRE for detection of proximal SB disease, however the risk of capsule retention should be considered.

Colonic inflammation in pediatric inflammatory bowel disease: detection with magnetic resonance enterography

BACKGROUND

Colonic involvement in pediatric inflammatory bowel disease is common. Magnetic resonance (MR) enterography is considered the best imaging modality for pediatric inflammatory bowel disease evaluation. It is unclear whether the lack of a dedicated large bowel preparation prevents a reliable colonic assessment.

OBJECTIVE

To determine the diagnostic performance of standard MR enterography in detecting and grading colonic inflammatory activity.

MATERIALS AND METHODS

We retrospectively evaluated children who underwent both MR enterography and ileocolonoscopy with biopsies <4 weeks apart. Two radiologists independently reviewed MR examinations and quantified inflammation in each of the five colonic segments using a standardized MR score system. Findings were compared with histological examination of the corresponding segment. Mann-Whitney, Kruskal-Wallis, Jonckheere-Terpstra and Bland-Altman statistics were used.

RESULTS

One hundred seventy-five segments from 37 examinations were included. MR enterography diagnostic performance for inflammation was as follows: sensitivity 94% (95% confidence interval [CI]: 90-97%), specificity: 64% (95% CI: 57-71%). A significant positive correlation was found between MR score and inflammatory activity histologically graded (P<0.001, Jonckheere-Terpstra test). The interobserver agreement was good (mean difference between MR enterography scores was -0.03; limits of agreement -2.8 to 2.7).

CONCLUSION

Standard MR enterography is sensitive for the detection of actively inflamed colonic segments. MR enterography might provide useful information for guiding biopsies and its role as an alternative to ileocolonoscopy in monitoring colonic disease activity in children should be further investigated.

Radiologic Predictors of Surgery in Newly Diagnosed Pediatric Crohn Disease Patients

OBJECTIVES

The aim of the present study was to assess whether small bowel imaging conducted at the time of diagnosis could be used as a predictor of small bowel surgical intervention in a population of pediatric patients with Crohn disease (CD).

METHODS

A retrospective analysis of small bowel imaging within 30 days of diagnosis of pediatric CD was conducted. Patients were divided into 2 groups based on small bowel imaging: those with no or minor abnormalities (71%) and those with more extensive or obstructive abnormalities (29%). Medical records were reviewed for small bowel surgical intervention and clinic follow-up visits.

RESULTS

A total of 232 patients were included in the study group (average age at diagnosis 11.7 years). Twenty-seven patients (12%) underwent small bowel surgical intervention. The relative risk for small bowel surgical intervention was 2.91 in the group with more extensive imaging abnormalities. The majority of increased surgical risk occurred in the first year after diagnosis, when the normal-minor group had a 2% surgical risk and the more abnormal group had a 17% surgical risk. Both groups had a 2% to 3% surgical risk per year after the first year.

CONCLUSIONS

Small bowel imaging at the time of diagnosis in pediatric CD can help predict the risk of small bowel surgical intervention and should be recommended for all newly diagnosed patients. Nearly one third of our cohort underwent small bowel surgical intervention through 8 years of follow-up. Surgical complications of CD often occur in the small bowel, and counseling families about surgical risk is an integral part of pediatric CD management.

The first joint ESGAR/ ESPR consensus statement on the technical performance of cross-sectional small bowel and colonic imaging

Objectives

To develop guidelines describing a standardised approach to patient preparation and acquisition protocols for magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound (US) of the small bowel and colon, with an emphasis on imaging inflammatory bowel disease.

Methods

An expert consensus committee of 13 members from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and European Society of Paediatric Radiology (ESPR) undertook a six-stage modified Delphi process, including a detailed literature review, to create a series of consensus statements concerning patient preparation, imaging hardware and image acquisition protocols.

Results

One hundred and fifty-seven statements were scored for agreement by the panel of which 129 statements (82 %) achieved immediate consensus with a further 19 (12 %) achieving consensus after appropriate modification. Nine (6 %) statements were rejected as consensus could not be reached.

Conclusions

These expert consensus recommendations can be used to help guide cross-sectional radiological practice for imaging the small bowel and colon.

Key points

• Cross-sectional imaging is increasingly used to evaluate the bowel

• Image quality is paramount to achieving high diagnostic accuracy

• Guidelines concerning patient preparation and image acquisition protocols are provided

Small intestine contrast ultrasonography for the detection and assessment of Crohn disease: A meta-analysis

BACKGROUND

Crohn disease (CD) is a chronic relapsing disease. Imaging modalities are essential for the diagnosis and assessment of CD. Small intestine contrast ultrasonography (SICUS) is a well-tolerated, noninvasive and radiation-free modality and has shown potential in CD assessment. We aimed at evaluating the diagnostic accuracy of SICUS in the detection and assessment of small-bowel lesions and complications in CD.

METHODS

We searched PubMed database for relevant studies published before April 24, 2016. We integrated the true positive, false positive, false negative, and true negative into the pooled estimates of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio. Forest plots were to represent the pooled results of all studies.

RESULTS

Thirteen articles were finally considered eligible. The pooled sensitivity and specificity of SICUS in detecting small-bowel lesions were 0.883 (95% confidence interval (CI) 0.847-0.913) and 0.861 (95% CI 0.828-0.890), respectively. The pooled diagnostic odds ratio was 39.123 (95% CI 20.014-76.476) and the area under the curve of summary receiver operating characteristic was 0.9273 (standard error: 0.0152). In subgroup analyses, SICUS represented fine sensitivity and specificity in proximal and distal small intestine lesion, as well as in CD-related complications such as stricture, dilation, abscess, and fistula.

CONCLUSION

SICUS is accurate enough to make a complete assessment about the location, extent, number, and almost all kinds of complications in CD small-bowel lesions.

Current tecniques and new perpectives research of magnetic resonance enterography in pediatric Crohn's disease

Crohn's disease affects more than 500000 individuals in the United States, and about 25% of cases are diagnosed during the pediatric period. Imaging of the bowel has undergone dramatic changes in the past two decades. The endoscopy with biopsy is generally considered the diagnostic reference standard, this combination can evaluates only the mucosa, not inflammation or fibrosis in the mucosa. Actually, the only modalities that can visualize submucosal tissues throughout the small bowel are the computed tomography (CT) enterography (CTE) with the magnetic resonance enterography (MRE). CT generally is highly utilized, but there is growing concern over ionizing radiation and cancer risk; it is a very important aspect to keep in consideration in pediatric patients. In contrast to CTE, MRE does not subject patients to ionizing radiation and can be used to detect detailed morphologic information and functional data of bowel disease, to monitor the effects of medical therapy more accurately, to detect residual active disease even in patients showing apparent clinical resolution and to guide treatment more accurately.

MR Enterographic Findings as Biomarkers of Mucosal Healing in Young Patients With Crohn Disease

OBJECTIVE

The purpose of this study was to investigate the MR enterographic findings that best correlate with mucosal healing assessed with ileocolonoscopy.

MATERIALS AND METHODS

Patients with Crohn disease who underwent two ileocolonoscopic examinations and also underwent MR enterography close in time to the second endoscopic examination were included in a retrospective study. Two pediatric gastroenterologists blinded to the imaging findings reviewed the endoscopic examinations to assess for mucosal healing, defined as resolution of inflammation within a bowel segment at subsequent ileocolonoscopy. Two radiologists blinded to endoscopic and clinical data interpreted the MR enterographic images. Sensitivity, specificity, and accuracy for mucosal healing were calculated for several imaging features.

RESULTS

A total of 30 patients (15 female patients, 15 male patients; age range, 8-24 years; mean, 17.2 ± 3.2 years) with pediatric-onset Crohn disease were examined. The average time between MR enterography and the second ileocolonoscopic examination was 12.7 ± 7.9 days. A total of 202 bowel segments from the terminal ileum to rectum were evaluated in the 60 ileocolonoscopic examinations. Forty-four bowel segments exhibited mucosal healing, and 37 segments exhibited persistent inflammation. At imaging, the MR index of activity score in mucosal healing segments was 6.6 ± 3.4, compared with 13.7 ± 9.7 in segments without mucosal healing (p = 0.0001). The average bowel wall thickness in healing segments was 2.7 ± 0.9 mm compared with 4.7 ± 3.1 mm in persistently inflamed segments (p = 0.0004). An MR index of activity score less than 8 had the highest accuracy for mucosal healing (accuracy, 74%; sensitivity, 84%; specificity, 62%; p < 0.0001). Mucosal hyperenhancement (72%, 98%, 41%), mesenteric hypervascularity (72%, 98%, 41%), bowel wall edema (72%, 93%, 46%), and bowel wall thickness less than 4 mm (72%, 84%, 57%) were also strongly associated with mucosal healing (p < 0.0003).

CONCLUSION

In this study MR enterography was accurate for assessing mucosal healing, an important therapeutic endpoint in pediatric patients with Crohn disease.

The Diagnostic Role of Magnetic Resonance Enterography as a Complementary Test to Colonoscopy in Active Crohn's Disease

BACKGROUND

According to recent studies comparing magnetic resonance enterography (MRE) with ileocolonoscopy for assessing inflammation of small bowel and colonic segments in adults with active Crohn’s disease (CD), we aimed to compare the accuracy of these two diagnostic methods in Iranian population.

METHODS

During 2013-2014 a follow-up study was done on 30 patients with active CD in a gastroenterology clinic affiliated to Tehran University of Medical Sciences. MRE and ileocolonoscopy were performed for all the patients. All statistical analyses were performed using SPSS (version 18) and p-value<0.05 was considered as statistically significant.

RESULTS

Of the 30 patients with active CD, 11(36.7%) were men and 19 (63.3%) were women with mean age of 37.30±13.66 years (range: 19-67 years). MRE had sensitivity and specificity of 50% and 90% with positive predictive value (PPV) and negative predictive value (NPV) of 71.43 and 78.26, respectively for localizing sigmoid lesions and ileum had sensitivity and specificity of 84.21 and 45.45 with PPV and NPV of 72.73 and 62.50, respectively.

CONCLUSION

While moderate sensitivity and high specificity of MRE in localizing colonic lesions makes it an appropriate confirmatory test after colonoscopy, the reported high sensitivity and moderate specificity of MRE versus colonoscopy in detecting ileal lesions makes it a suitable screening test for ileal lesions. Finally we can conclude that MRE can be an important complementary test to colonoscopy in detecting active disease.

Detecting inflammation in the unprepared pediatric colon - how reliable is magnetic resonance enterography?

BACKGROUND

Pediatric inflammatory bowel disease frequently affects the colon. MR enterography is used to assess the small bowel but it also depicts the colon.

OBJECTIVE

To compare the accuracy of MR enterography and direct visualization at endoscopy in assessing the colon in pediatric inflammatory bowel disease.

MATERIALS AND METHODS

We included children with inflammatory bowel disease who had undergone both MR enterography and endoscopy, and we restrospectively assessed the imaging and endoscopic findings. We scored the colonic appearance at MR using a total colon score. We then compared scores for the whole colon and for its individual segments with endoscopy and histology.

RESULTS

We included 15 children. An elevated MR colonic segmental score predicted the presence of active inflammation on biopsy with a specificity of 90% (95% confidence interval [CI] 79.5-96.2%) and sensitivity of 60% (CI 40.6-77.3%); this compares reasonably with the predictive values for findings at colonoscopy - specificity 85% (CI 73.4-92.9%) and sensitivity 53.3% (CI 34.3%-71.6%). Accuracy did not change significantly with increasing bowel distension.

CONCLUSION

MR-derived scores had comparable accuracy to those derived during visualization at colonoscopy for detecting biopsy-proven inflammation in our patient group. MR enterography might prove useful in guiding biopsy or monitoring treatment response. Collapse of a colonic segment did not impair assessment of inflammation.

Magnetic Resonance Enterography Healing and Magnetic Resonance Enterography Remission Predicts Improved Outcome in Pediatric Crohn Disease

BACKGROUND

Mucosal healing predicts clinical remission and improved outcomes in patients with Crohn disease (CD). Magnetic resonance enterography (MRE) is a noninvasive imaging modality that can assess small and large bowel wall inflammation. Evidence suggests that MRE may be an acceptable alternative to evaluate mucosal healing over endoscopy. Our objective is to determine whether MRE remission predicts clinical remission at follow-up in children with CD.

METHODS

We performed an institutional review board-approved retrospecitve chart review using our prospectively maintained MRE CD database. Inclusion criteria were all children who underwent an MRE more than 6 months after diagnosis with CD who had follow-up of at least 1 year from imaging.

RESULTS

A total of 101 children with CD underwent MRE, a median of 1.3 years from diagnosis with a median follow-up of 2.8 years after MRE. Active inflammation was detected in 65 MRE studies, whereas 36 MRE studies demonstrated MRE remission. A total of 88.9% of children demonstrating MRE remission were in clinical remission at follow-up, whereas only 44.6% of those demonstrating MRE active inflammation achieved clinical remission. Children demonstrating MRE-active inflammation were more likely to have a change in medication (44.6% vs 8.3%) and more likely to undergo surgery (18.5% vs 2.8%).

CONCLUSIONS

MRE remission is associated with clinical remission at follow-up at least 1 year after MRE. MRE remission was associated with fewer medication changes and fewer surgeries suggesting that, similar to endoscopic remission, MRE remission demonstrates improved outcome. Additional research is needed to confirm that MRE can be used as a surrogate for mucosal healing.

The Role of MR Enterography in Assessing Crohn's Disease Activity and Treatment Response

MR enterography (MRE) has become the primary imaging modality in the assessment of Crohn's disease (CD) in both children and adults at many institutions in the United States and worldwide, primarily due to its noninvasiveness, superior soft tissue contrast, and lack of ionizing radiation. MRE technique includes distention of the small bowel with oral contrast media with the acquisition of T2-weighted, balanced steady-state free precession, and multiphase T1-weighted fat suppressed gadolinium contrast-enhanced sequences. With the introduction of molecule-targeted biologic agents into the clinical setting for CD and their potential to reverse the inflammatory process, MRE is increasingly utilized to evaluate disease activity and response to therapy as an imaging complement to clinical indices or optical endoscopy. New and emerging MRE techniques, such as diffusion-weighted imaging (DWI), magnetization transfer, ultrasmall superparamagnetic iron oxide- (USPIO-) enhanced MRI, and PET-MR, offer the potential for an expanded role of MRI in detecting occult disease activity, evaluating early treatment response/resistance, and differentiating inflammatory from fibrotic strictures. Familiarity with MR enterography is essential for radiologists and gastroenterologists as the technique evolves and is further incorporated into the clinical management of CD.

Particularities of Crohn's disease in pediatric patients: current status and perspectives regarding imaging modalities

A consensus on the best imaging modality evaluating inflammatory bowel disease in the pediatric population is lacking and it is often unclear which modality to choose in specific clinical circumstances. Children with inflammatory bowel disease are exposed to ionizing radiation from multiple imaging studies performed at initial diagnosis, throughout treatment and during the follow-up period. This paper discusses the value of different imaging techniques in pediatric patients with inflammatory bowel disease and gives a review of the literature. In addition, particular features of inflammatory bowel disease in children including the predilection of affected segments in the gastrointestinal tract are highlighted. Based on current literature knowledge, we encourage an integrative approach to the interpretation of clinical and imaging data for diagnosis and follow-up in daily clinical settings.

Use of Imaging Techniques in Inflammatory Bowel Diseases That Minimize Radiation Exposure

The use of imaging in the management of inflammatory bowel disease (IBD) has grown exponentially in the last few years. This has raised concerns about the risk of high cumulative level of radiation exposure from medical imaging in IBD patients during their lifetime, especially when the disease begins in pediatric age. Physicians caring for IBD children should be aware of the malignant potential of ionizing radiation and of the availability of alternative radiation-free techniques such as magnetic resonance imaging (MRI) and ultrasonography (US), in order to use them whenever possible. This review will focus on the value of US and MRI in pediatric IBD.

Imaging of perianal fistulizing Crohn's disease

Perianal fistula is a complication of Crohn's disease that carries a high morbidity. It is a channel that develops between the lower rectum, anal canal and perianal or perineal skin. The development of perianal fistulas typically connotes a more aggressive disease phenotype and may warrant escalation of treatment to prevent poor outcomes over time. Based on fistula anatomy, debris can form inside these tracts and cause occlusion, which subsequently leads to abscess formation, fever and malaise. The clinical presentation is often with complaints of pain, continuous rectal drainage of fecal matter as well as malodorous discharge. Considering that the presence of fistulas often indicates refractory and aggressive disease, early identification of its presence is important. Some patients may not have the classic symptoms of fistulizing disease at presentation and others may have significant scarring and/or pain from previous fistulizing episodes, which can make an accurate assessment on physical exam alone problematic. As a result, utilizing diagnostic imaging is the best means of identifying the early signs of perianal fistulas or abscess formation in these patients. Several imaging modalities exist which can be used for diagnosis and management. Endoscopic ultrasound and pelvic MRI are considered the most useful in establishing the diagnosis. However, a combination of multiple imaging modalities and/or examination under anesthesia is probably the most ideal. Incomplete characterization of the fistula tract(s) extent or the presence of abscess carries a high morbidity and far-reaching personal expense for the patient - promoting worsening of the disease.

Advances in imaging to allow personalized medicine in Crohn's disease

Crohn's disease is a destructive inflammatory bowel disease of unknown origin that may lead to various complications such as strictures, stenosis, fistulas and colitis-associated neoplasias. However, the course of the disease varies substantially among patients and disease behaviour may also change with time. At diagnosis behaviour is inflammatory in the majority of patients, while penetrating or structuring behaviour become more prominent at later time points. Thus, medication in Crohn's disease needs frequent optimization over time. Therefore, new strategies for prediction of response to therapy are urgently needed. Here, recent advantages in imaging techniques for personalized medicine in Crohn's disease are reviewed. Such advantages include ultrasonography, computed tomography, magnetic resonance imaging and new endoscopic approaches such as molecular endoscopy. It is expected that these novel techniques will lead to marked improvements in the assessment of disease behaviour and the prediction of response to clinical therapy with biologicals.

Curcumin and inflammatory bowel disease: potential and limits of innovative treatments

Curcumin belongs to the family of natural compounds collectively called curcuminoids and it possesses remarkable beneficial anti-oxidant, anti-inflammatory, anti-cancer, and neuroprotective properties. Moreover it is commonly assumed that curcumin has also been suggested as a remedy for digestive diseases such as inflammatory bowel diseases (IBD), a chronic immune disorder affecting the gastrointestinal tract and that can be divided in two major subgroups: Crohn’s disease (CD) and Ulcerative Colitis (UC), depending mainly on the intestine tract affected by the inflammatory events. The chronic and intermittent nature of IBD imposes, where applicable, long-term treatments conducted in most of the cases combining different types of drugs. In more severe cases and where there has been no good response to the drugs, a surgery therapy is carried out. Currently, IBD-pharmacological treatments are generally not curative and often present serious side effects; for this reason, being known the relationship between nutrition and IBD, it is worthy of interesting the study and the development of new dietary strategy. The curcumin principal mechanism is the suppression of IBD inflammatory compounds (NF-κB) modulating immune response. This review summarizes literature data of curcumin as anti-inflammatory and anti-oxidant in IBD, trying to understand the different effects in CD e UC.