Assessment of disease behavior in patients with Crohn's disease by MR enterography.

BACKGROUND: Magnetic resonance imaging (MRI) of the bowel is an increasingly used modality to evaluate patients with Crohn's disease. The Montreal classification of the disease behavior is considered as an excellent prognostic and therapeutic parameter for these patients. In our study, we correlated the behavior assessment performed by a radiologist based on MRI with the surgeons' clinical assessment based on the assessment during abdominal surgery. METHODS: We evaluated 76 patients with Crohn's disease, who underwent bowel resection and had an MRI within 4 weeks before surgery. Radiological behavior assessment was performed by 2 radiologists based on MRI. Behavior was classified into B1 (nonstricturing and nonpenetrating), B2, and B3 (penetrating) disease. Surgical assessment was done by the same surgeon, who performed all bowel resections, based on intraoperative findings and histologic results. RESULTS: The surgical assessment identified 4 patients (5%) as B1, 16 patients (21%) as B2, and 56 patients (74%) as B3. In 97% (n = 74) of all patients, the intraoperative and radiological assessment were identical with interobserver agreement of 0.937. In one case, B2 was radiological considered as B1, and in another case, B3 was diagnosed as B2. The diagnosis of a stricture had the highest sensitivity of 96%, whereas the detection of inflammatory mass showed the lowest sensitivity of 81%. Abscesses had the lowest positive predictive value of 68% with a specificity of 88%. Best correlation was found for fistulae (0.895). CONCLUSIONS: MRI represents an excellent imaging modality to correctly assess the Montreal classification-based disease behavior in patients scheduled for bowel resection with Crohn's disease.

Comparison of high-resolution ultrasound and MR-enterography in patients with inflammatory bowel disease.

AIM: To compare the results of high-resolution ultrasound (HR-US) and magnetic resonance enterography (MRE) examinations in patients with inflammatory bowel disease (IBD). METHODS: The reports of 250 consecutive cases with known IBD, who had an MRE and HR-US examination, were retrospectively analyzed. Using a patient-based approach we evaluated morphological disease features such as affected bowel wall, stenosis, abscess and fistula. The comparison between the two modalities was based on the hypothesis, that any pathological change described in any imaging modality was a true finding, as no further standard of reference was available for complete assessment. RESULTS: Two hundred and fifty examinations representing 207 different patients were evaluated. Both modalities assessed similar bowel wall changes in 65% of the examinations, with more US findings in 11% and more MRE findings in 15%. When the reports were analyzed with regard to "bowel wall inflammation", US reported more findings in 2%, while MRE reported more findings in 53%. Stenoses were assessed to be identical in 8%, while US found more in 3% and MRE in 29% (P < 0.01). For abscess detection, US showed more findings in 2% (n = 4) while MRE detected more in 6% (n = 16). US detected more fistulas in 1% (n = 2), while MRE detected more in 13% (n = 32) (P < 0.001). The most common reason for no detected pathology by US was a difficult to assess anatomical region (lesser pelvis, n = 72). CONCLUSION: US can miss clinically relevant pathological changes in patients with IBD mostly due to difficulty in assessing certain anatomical regions.

Influence of percutaneous abscess drainage on severe postoperative septic complications in patients with Crohn's disease.

PURPOSE: Severe postoperative intra-abdominal septic complications (IASC) such as an anastomotic leak, intra-abdominal abscess, and fistula are significantly associated with the presence of spontaneous intra-abdominal abscess at the time of laparotomy in patients with Crohn's disease (CD). The purpose of this study was to compare the incidence of severe postoperative IASC in patients undergoing intestinal resections with and without preoperative percutaneous abscess drainage (PAD) before definitive surgery. METHODS: Using a prospective surgical database, we searched for patients with CD and spontaneous intra-abdominal abscesses who underwent intestinal resection at our hospital from May 2005 to February 2009. Postoperative IASC were defined as anastomotic leaks, abscess, and fistula within 1 month after surgery. We compared the incidence of postoperative IASC in patients with (group I) and without (group II) preoperative PAD (Fisher's exact test). RESULTS: We identified 25 patients (15 men, 10 women; mean age, 31 years) with spontaneous intra-abdominal abscesses. PAD was performed in 12 of 25 patients (48%), with an average of 37 days before surgery (range, 6-83 days). The overall rate of postoperative IASC was 48% (12 of 25 patients). In group I, postoperative IASC occurred in 3 of 12 patients (25%). In group II, postoperative IASC were assessed in 9 of 13 patients (69%). The differences between these two groups were considered to be statistically significant (p = 0.04). CONCLUSION: PAD of intra-abdominal abscesses before surgery could significantly reduce the occurrence of severe postoperative IASC in patients with CD.