Radiographic Evaluation of Ileal Pouch Disorders: A Systematic Review

BACKGROUND

Radiographic imaging of the abdomen and pelvis plays an important role in the diagnosis and management of ileal pouch disorders with modalities including CT, MRI, contrasted pouchography, and defecography.

OBJECTIVES

To perform a systematic review of the literature and describe applications of cross-sectional imaging, pouchography, defecography, and ultrasonography.

DATA SOURCES

PubMed, Google Scholar, and Cochrane database.

STUDY SELECTION

Relevant articles on endoscopy in ileal pouches published between January 2003 and June 2023 in English were included on the basis of Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

INTERVENTION

Main abdominal and pelvic imaging modalities and their applications in the diagnosis of ileal pouch disorders were included.

MAIN OUTCOME MEASURES

Accuracy in characterization of ileal pouch disorders.

RESULTS

CT is the test of choice for the evaluation of acute anastomotic leaks, perforation, and abscess(es). MRI of the pelvis is suitable for the assessment of chronic anastomotic leaks and their associated fistulas and sinus tracts, as well as for the penetrating phenotype of Crohn's disease of the pouch. CT enterography and magnetic resonance enterography are useful in assessing intraluminal, intramural, and extraluminal disease processes of the pouch and prepouch ileum. Water-soluble contrast pouchography is particularly useful for evaluating acute or chronic anastomotic leaks and outlines the shape and configuration of the pouch. Defecography is the key modality to evaluate structural and functional pouch inlet and outlet obstructions. Ultrasonography can be performed to assess the pouch in experienced IBD centers.

LIMITATIONS

This is a qualitative, not quantitative, review of mainly case series and case reports.

CONCLUSIONS

Abdominopelvic imaging, along with clinical and endoscopic evaluation, is imperative for accurately assessing structural, inflammatory, functional, and neoplastic disorders. See video from symposium .

Ouch, my pouch! a clinician's guide to pouchitis

Pouchitis is defined as inflammation of the ileal pouch created during a restorative proctocolectomy with ileal pouch-anal anastomosis. Although the incidence of this inflammatory condition is high, the exact etiology often remains unclear and the management challenging. In this review, we summarize the clinical presentation, pathogenesis, diagnosis, and management of this common complication.

Sensitivity and specificity of diagnostic modalities in pouchitis: a systematic review and meta-analysis

Restorative proctocolectomy (RPC) is the most common surgical procedure to restore gastrointestinal continuity after surgical resection of the colon and rectum. Pouchitis is a common complication with several different modalities that can be used to aid diagnosis. This systematic review and meta-analysis aimed at exploring the sensitivity and specificity these diagnostic modalities. The medical literature was searched using MEDLINE, EMBASE and EMBASE classic and PubMed from 1978 to June 2022. We calculated descriptive statistics using sensitivity, specificity, and false-positive rate of the primary studies and also their positive and negative likelihood ratios, and their diagnostic odds ratios. The screen found 5477 records with 13 studies being included. Faecal lactoferrin was found to have the highest pooled sensitivity and specificity of 98% and 88% respectively with imaging modalities coming in second and faecal calprotectin third with pooled sensitivities and specificities of 87% and 79% and 74% and 81% respectively. Faecal biomarkers particularly lactoferrin and imaging modalities may have an important role to play in diagnosing pouchitis. Importantly due to delays in availability of pouchoscopy, our data supports early ordering of these tests to help delineate from other causes. Further studies are required with larger cohort sizes to further validate these tests.

Role of MR enterography versus ileo-colonoscopy in the assessment of inflammatory bowel diseases

Background

Inflammatory bowel disease (IBD) is widespread and rapidly rising in developing countries. It remains a significant issue in Western culture with a prevalence of more than 0.3%. Symptom control has been the only focus of treatment before the discovery that many individuals with IBD continue to have disease activity even in the absence of clinical symptoms. Therefore, treatment goals now include establishing clinical remission, steroid-free remission, and mucosal healing, which may eventually be complemented by transmural healing in cross-sectional imaging modalities. Magnetic resonance enterography (MRE), computed tomography enterography, and small-bowel ultrasound are now reliable methods for staging intramural lesions and extramural consequences in CD and for determining disease activity and severity. Recently literature suggests the incorporation of (MRE) for periodic reevaluation of IBD patients, as it offers small-bowel, colonic, and extra-enteric assessment as well as monitors the response to the anti-inflammatory therapy. The purpose of the current study was to compare MRE with ileo-colonoscopy findings in the diagnosis of IBD features, specifically Crohn's disease, and ulcerative colitis, as well as in the detection of disease exacerbation (Activity).

Results

This study used MRE and ileo-colonoscopy to assess chronic inflammatory bowel disease patients; the patient population (n = 30) was made up of (14/30, 46.7%) females and (16/30, 53.3%) males, with a mean age of 32 ± SD 13 years. MRE alone detected lymphadenopathy in 73.3% of patients, and mural thickening with a mean of 4.1 ± SD 5.1 mm. It has detected mucosal enhancement with 80% sensitivity and 60% specificity. However, it was unable to detect mucosal erosions or ulceration.

Conclusions

MRE is sensitive, inexpensive, noninvasive, and radiation-free for inflammatory bowel disease detection, with 86.7% diagnostic accuracy for affected areas. Unlike ileo-colonoscopy, it could examine the entire small intestine, precisely measure the affected loop, and detect activity signs such as mural thickening and lymphadenopathy. Only ileo-colonoscopy could detect mucosal degradation and superficial ulcers. IBD treatment protocols should incorporate MRE for small-bowel, colonic, and extra-enteric assessment, monitoring of disease activity, and anti-inflammatory therapy response.

ECCO-ESGAR Topical Review on Optimizing Reporting for Cross-Sectional Imaging in Inflammatory Bowel Disease

BACKGROUND AND AIMS

The diagnosis and follow up of patients with inflammatory bowel disease [IBD] requires cross-sectional imaging modalities, such as intestinal ultrasound [IUS], magnetic resonance imaging [MRI] and computed tomography [CT]. The quality and homogeneity of medical reporting are crucial to ensure effective communication between specialists and to improve patient care. The current topical review addresses optimized reporting requirements for cross-sectional imaging in IBD.

METHODS

An expert consensus panel consisting of gastroenterologists, radiologists and surgeons convened by the ECCO in collaboration with ESGAR performed a systematic literature review covering the reporting aspects of MRI, CT, IUS, endoanal ultrasonography and transperineal ultrasonography in IBD. Practice position statements were developed utilizing a Delphi methodology incorporating two consecutive rounds. Current practice positions were set when ≥80% of the participants agreed on a recommendation.

RESULTS

Twenty-five practice positions were developed, establishing standard terminology for optimal reporting in cross-sectional imaging. Assessment of inflammation, complications and imaging of perianal CD are outlined. The minimum requirements of a standardized report, including a list of essential reporting items, have been defined.

CONCLUSIONS

This topical review offers practice recommendations to optimize and homogenize reporting in cross-sectional imaging in IBD.

ACR Appropriateness Criteria® Anorectal Disease

This review summarizes the relevant literature for the selection of the initial imaging in 4 clinical scenarios in patients with suspected inflammatory disease or postoperative complication of the anorectum. These clinical scenarios include suspected perianal fistula or abscess; rectovesicular or rectovaginal fistula; proctitis or pouchitis; and suspected complication following proctectomy, coloproctectomy, or colectomy with a pouch or other anastomosis. The appropriateness of imaging modalities as they apply to each clinical scenario is rated as usually appropriate, may be appropriate, and usually not appropriate to assist the selection of the most appropriate imaging modality in the corresponding clinical scenarios of anorectal disease. 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 AND MANAGEMENT APPROACH TO POUCHITIS IN INFLAMMATORY BOWEL DISEASE

In patients with ulcerative colitis refractory to medical therapy, total proctocolectomy and posterior ileal-anal pouch anastomosis is the standard surgical therapy. One of the possible complications is pouchitis. Depending on the duration of the symptoms, it can be classified as acute, recurrent, or chronic. The latter, according to the response to therapy, can be defined as antibiotic-dependent or refractory. The treatment of pouchitis is based on the use of antibiotics and probiotics. Thiopurine and biological therapy have been suggested in patients with refractory pouchitis. Special care should be taken in the endoscopic surveillance of these patients, especially if they present risk factors such as dysplasia or previous colorectal cancer, primary sclerosing cholangitis or ulcerative colitis for more than 10 years.

Abnormal Pouchogram Predicts Pouch Failure Even in Asymptomatic Patients

BACKGROUND

Anastomotic complications after restorative total proctocolectomy with IPAA for ulcerative colitis alter functional outcomes and quality of life and may lead to pouch failure. Routine contrast enema of the pouch assesses anastomotic integrity before ileostomy reversal, but its clinical use is challenged.

OBJECTIVE

The purpose of this research was to assess the relationship among preoperative clinical characteristics, abnormal pouchography, and long-term pouch complications.

DESIGN

This was a retrospective chart review.

SETTINGS

The study was conducted at a tertiary care center between 2000 and 2010.

PATIENTS

Ulcerative colitis patients with IPAA undergoing pouchography before ileostomy closure were included.

MAIN OUTCOME MEASURES

Patient demographics, incidence of pouch-related complications, and findings on pouchogram were recorded. Primary outcome was pouch failure, defined as excision or permanent diversion of the ileoanal pouch. Independent predictors of pouch failure were determined by multivariate regression.

RESULTS

A total of 262 patients with ulcerative colitis were included. Contrast extravasation was seen in 27 patients (10.3%): 14 (51.9%) were clinically asymptomatic at the time of pouchogram. Six (22.2%) of 27 patients with extravasation developed pouch failure despite normalization of the pouchogram before ileostomy closure. Forty patients (15.3%) were found to have pouch-anal anastomotic stenosis; only 1 developed pouch failure. Pre-IPAA serum albumin and hemoglobin levels were inversely associated with contrast extravasation (serum albumin: OR = 0.42; hemoglobin: OR = 0.77; p < 0.05). Contrast extravasation was associated with delayed takedown operation (average = 67 d), increased risk (OR = 5.25; p < 0.01), and shorter time (median = 32.0 vs 72.5 mo; HR = 5.88; p < 0.05) to pouch failure, as well as increased risk of pouch-related complications (p < 0.05).

LIMITATIONS

The study was limited by its retrospective nature and small number of patients who developed pouch failure.

CONCLUSIONS

Pouchography before ileostomy takedown is useful in identifying patients with ulcerative colitis at risk for postoperative complications. Radiologic resolution of IPAA-related leak does not reliably predict healing; caution is warranted in this subgroup. See Video Abstract at http://links.lww.com/DCR/A818.

Are radiologic pouchogram and pouchoscopy useful before ileostomy closure in asymptomatic patients operated for ulcerative colitis?

OBJECTIVES

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the "gold standard" procedure for patients with ulcerative colitis (UC) requiring surgical intervention. A de-functioning ileostomy is usually performed, as a step for the IPAA procedure. The aim of this study is to present the methodology and results of the routine double assessment of IPAA integrity in asymptomatic patients prior to the ileostomy reversal and evaluate its necessity.

METHODS

This is a retrospective study of 61 UC patients, who underwent IPAA construction, in 2010-2016. A diverting ileostomy was created after IPAA construction, which was reversed at least 3 months later. A double assessment, with pouchogram and pouchoscopy, of IPAA integrity was performed, before stoma closure. Post-operative symptoms and signs of complications, imaging studies, and endoscopic findings were recorded during follow-up.

RESULTS

Prior to the ileostomy reversal, both pouchoscopy and pouchogram identified no patient with evidence of anastomotic leakage. During a mean follow-up of 3.67 years after ileostomy reversal, 11 patients developed complications but only one had signs of leakage, which presented as a pouch-vaginal fistula. The specificity of both the pouchogram and pouchoscopy reached 100% and the negative predictive value ranged between 98.4 and 100%.

CONCLUSIONS

The specificity of pouchoscopy and pouchogram prior to ileostomy closure, in asymptomatic patients with IPAA for UC, is very high in recognizing an intact anastomosis, but their combination did not alter the diagnostic accuracy or had any effect in further management. At least, pouchogram could be selectively performed only in patients with high-risk clinical indicators.

KEY POINTS

• The double assessment of ileal pouch-anal anastomosis with pouchogram and pouchoscopy, prior to ileostomy closure, specifically in patients with ulcerative colitis has not been evaluated before. • The specificity of pouchoscopy and pouchogram prior to ileostomy closure, in asymptomatic patients with IPAA for UC, is very high in recognizing an intact anastomosis. • However, their combination did not alter the diagnostic accuracy or had any effect in further management, in asymptomatic patients.

MRI defecography of the ileal pouch-anal anastomosis-contributes little to the understanding of functional outcome

PURPOSE

Variability in functional outcome after ileal pouch-anal anastomosis (IPAA) is to a large extent unexplained. The aim of this study was to use MRI to evaluate the morphology, emptying pattern and other pathology that may explain differences in functional outcome between well-functioning and poorly functioning pouch patients. A secondary aim was to establish a reference of normal MRI findings in pelvic pouch patients.

METHODS

From a previous study, the best and worst functioning patients undergoing IPAA surgery between 2000 and 2013 had been identified and examined with manovolumetric tests (N = 47). The patients were invited to do a pelvic MRI investigating pouch morphology and emptying patterns, followed by a pouch endoscopy.

RESULTS

Forty-three patients underwent MRI examination. We found no significant morphological or dynamic differences between the well-functioning and poorly functioning pouch patients. There was no correlation between urge volume and the volume of the bony pelvis, and no correlation between emptying difficulties or leakage and dynamic MRI findings. Morphological MRI signs of inflammation were present in the majority of patients and were not correlated to histological signs of inflammation. Of the radiological signs of inflammation, only pouch wall thickness correlated to endoscopic pouchitis disease activity index scores.

CONCLUSION

It seems MRI does not increase the understanding of factors contributing to functional outcome after ileal pouch-anal anastomosis. Unless there is a clinical suspicion of perianal/peripouch disease or pelvic sepsis, MRI does not add value as a diagnostic tool for pelvic pouch patients. Endoscopy remains the golden standard for diagnosing pouch inflammation.

Capsule Endoscopy Validation of the Magnetic Enterography Global Score in Patients with Established Crohn's Disease

BACKGROUND AND AIMS

Capsule endoscopy [CE] and magnetic resonance enterography [MRE] are prime modalities for evaluation of the small bowel in Crohn's disease [CD]. Detection of proximal small bowel [SB] inflammation in CD by MRE is challenging. Currently available quantitative MRE scores do not incorporate proximal SB data. The MRE global score [MEGS] was designed for quantitative evaluation of the entire digestive tract; its accuracy in the proximal SB has not previously been evaluated. This study compared the evaluation of the small bowel inflammation by MEGS and CE-derived quantitative score (the Lewis score[LS]).

METHODS

CD patients in stable clinical remission were prospectively recruited and underwent MRE and CE; faecal calprotectin [FC] levels were obtained. MEGS was calculated for each SB segment and the entire SB [SBMEGS]. SB inflammation on CE was quantified using LS. A cumulative Lewis score [C-LS] was calculated based on summation of three tertiles scores.

RESULTS

Fifty patients were included. There was a significant correlation of SBMEGS with LS and C-LS [r = 0.61 and 0.71, both p = 0.001]. The correlation with FC was stronger for MEGS than for LS or C-LS [r = 0.68 vs r = 0.46 vs r = 0.53, all p = 0.001]. The correlation between the proximal LS and MEGS was significant [r = 0.55, p = 0.001]; median MEGS was significantly different in patients, with LS values consistent with mucosal healing, mild and moderate-to-severe inflammation.

CONCLUSIONS

MEGS provides accurate evaluation of the SB and strongly correlates with FC; the main advantage of MEGS is the accurate quantification of proximal SB inflammation unavailable for alternative MRE scores.