http://www.docguide.com/news/content.nsf/news/8525697700573E1885256DF600802013?OpenDocument&c=Diagnostic%20Radiology&count=10 By W. A. Thomasson, PhD
CHICAGO, IL -- December 8, 2003 -- "Virtual colonoscopy" with magnetic resonance imaging (MRI) for the diagnosis and monitoring of inflammatory bowel disease in children can be done without the usual cleansing to free the bowel of ***. This was the conclusion of a study presented here December 5th at the Annual Meeting of the Radiological Society of North America.
Faeces are normally bright on MRI due to their magnesium content, thus interfering with visualisation of the colon and its lumen. Pasquale Paolantonio, MD, and his colleagues at the University of Rome "La Sapienza," Rome, Italy, avoid this problem by having patients take 150 ml of highly concentrated barium sulfate with every major meal for 3 days. A diet high in iron is also prescribed for this period. When the colon is then distended with a water enema for the colonoscopy procedure, the entire lumen is dark: Tagging with barium sulfate renders the faeces, although present, effectively invisible to the imaging device.
Dr. Paolantonio and his colleagues demonstrated this technique in 10 children, aged 5 to 16 years, with inflammatory bowel disease. All subjects tolerated the procedure well, and, in all cases, the faeces were completely tagged and invisible on MRI. Residual air did not cause significant problems, and the software employed handled all motion artifacts without difficulty.
As Dr. Paolantonio demonstrated during his presentation, image quality was entirely adequate to identify ulcerative colitis in 7 subjects and Crohn's disease in 3. Thickening of the colonic wall, pseudopolyps of the mucosa, loss of haustral folds, and parietal enhancement could all be demonstrated. Dr. Paolantonio indicated that the ability to define thickening of the colonic wall and extension of inflammation would allow patients to be monitored on this basis. Improved patient compliance renders it a highly promising technique.
[Study Title: Unprepared MR Colonography in Pediatric Patients with Inflammatory Bowel Disease. Abstract T11-1479]