Magnetic Resonance Enteroclysis imaging of Crohn's.

Objective: The aim of our prospective study was to evaluate the diagnostic accuracy of MR Enteroclysis (MRE) to assess the extension and complications of Crohn's Disease (CD) in comparison with conventional enteroclysis (CE).

Methods: The study comprised 30 consecutive patients affected by Crohn's disease (18 women and 12 men; age range 16-76, mean age 40.6 years), who underwent conventional and MR enteroclysis. The MR enteroclysis protocol includes three sequences: coronal and axial FIESTA and ssFSE sequences and T1-3D-FSPGR sequences before and after intravenous injection of gadolinium, acquired after administration of 1.6-2 l of iso-osmolar polyethylene glycol solution via a nasojejunal catheter. Two radiologists blindly scored each sequence for opacification of the lumen, small bowel distension and image quality and evaluated the following parameters: presence of wall ulcers, pseudopolyps, stenoses and fistulae.

Results: The accuracy of the FIESTA sequence was significantly higher (p<0.01) than the ssFSE and 3D FSPGR sequences in the evaluation of lumen opacification and bowel distension, and for the overall quality of the images (p<0.01). The sensitivity and specificity of MRE were 82% and 100% for the visualisation of parietal ulcers, 87% and 100% for pseudopolyps, 100% and 88% for stenoses, 75% and 100% for parietal fistulae. High-grade stenoses with prestenotic dilation (n=6) and low-grade stenoses (n=9) were visualised both by MRE and CE. MRE also showed abscesses in two patients, not seen at CE. The FIESTA and ssFSE sequences had higher accuracy in the detection of wall ulcers and fistulae, whereas the 3D FSPGR sequences showed higher accuracy in the evaluation of wall thickening.

Conclusions: MRE is able to demonstrate the spectrum of superficial, intramural and exoenteric alterations in Crohn's disease and closely correlates with CE in demonstrating alterations of the bowel lumen and wall.