Correlation of MRI-determined small bowel Crohn’s disease categories with medical response and surgical pathology

AIM: To determine whether magnetic resonance imaging (MRI) can be used to categorize small bowel Crohn's disease (SB CD) into groups that correlate with response to medical therapy and surgical pathology.METHODS: Data was collected from all patients with MRI evidence of SB CD without significant colonic disease over a 32-mo period. Two radiologists, blinded to clinical findings, evaluated each MRI and grouped them based on bowel wall thickness and wall enhancement. These categories were: (1) "fibrosis", (2) "mild segmental hyper-enhancement and mild wall thickening", (3) "mild segmental hyper-enhancement and marked wall thickening", (4) "marked segmental transmural hyper-enhancement". Patient response to additional medical therapy post-MRI was prospectively determined at 8-wk. Non-responders underwent endoscopy and were offered therapeutic endoscopy or surgery. Surgical pathology was assessed against the MRI category. RESULTS: Fifty-five patients were included. Females and category "2" patients were more likely, and patients with luminal narrowing and hold-up less likely, to respond to medical therapy (P < 0.05). Seventeen patients underwent surgery. The surgical pathologicalfindings of fibrosis and the severity of inflammation correlated with the MRI category in all cases.CONCLUSION: Our fi ndings suggest that SB CD can be grouped by the MRI f indings and that these groups are associated with patients more likely to respond to continued medical therapy. The MRI categories also correlated with the presence and level of intestinal inflammation and fibrosis on surgical pathology, and may be of prognostic use in the management of CD patients.

Small bowel MRI enteroclysis or follow through:Which is optimal?

AIM:To determine if a nasojejunal tube(NJT) is required for optimal examination of enteroclysis and if patients can be examined only in the supine position.METHODS:Data were collected from all patients undergoing small bowel(SB) magnetic resonance imaging(MRI) examination over a 32-mo period.Patients either underwent a magnetic resonance(MR) follow-through(MRFT) or a MR enteroclysis(MRE) in the supine position.The quality of proximal and distal SB distension as well as the presence of motion artefact and image quality were assessed by 2 radiologists.RESULTS:One hundred and fourteen MR studies were undertaken(MRFT-49,MRE-65) in 108 patients in the supine position only.Image artefact was more frequent in MRE than in MRFT(29.2% vs 18.4%) ,but was not statistically significant(P = 0.30) .Adequate distension of the distal SB was obtained in 97.8% of MRFT examinations and in 95.4% of MRE examinations,respectively.Proximal SB distension was,however,less frequently optimal in MRFT than in MRE(P = 0.0036) ,particularly in patients over the age of 50 years(P = 0.0099) .Image quality was good in all examinations.CONCLUSION:All patients could be successfully imaged in the supine position.MRE and MRFT are equivalent for distal SB distension and artefact effects.Proximal SB distension is frequently less optimal in MRFT than in MRE.MRE is,therefore,the preferred MR examination method of the SB.