USG and MRI for IBD
Published by Vijay March 13th, 2009 in CT, MRI, Medical Research, Medicine, News, Radiology, Ultrasonography…
US researchers conducted a meta-analysis of 33 prospective studies assessing these techniques which used histopathology, ileocolonoscopy, and/or intraoperative findings as the reference standard.
The authors said: “Because of the relapsing nature of IBD and the young age at which it usually develops, frequent re-evaluation of disease is necessary in many patients. Therefore, it might be preferable to use a technique that does not involve ionizing radiation.”
They added: “Although CT is widely used to evaluate IBD, the findings of our meta-analysis, as well as the relatively large radiation dose and the intravenous iodine-based contrast medium needed for CT, favour the use of ultrasound or MRI.”
But Dr Mark Baker, of the radiology division of the Cleveland Clinic in Ohio, US, disagreed. He cautioned: “Like any meta-analysis, the conclusions are only as good as the data.
My opinion: Not likely to catch on.
Reasons: Ultrasonography for bowel disorders is technically demanding and is extremely dependent on the proficiency of the performer & patient factors, such as presence or abscence of bowel gas, ascites, pain, etc. For MRI, I cite the usual disadvantages - adequately advanced equipment are not available in all places; takes longer to perform & requires a cooperative patient.
I don’t think it is possible to do away with CT for diagnosis of IBD and its complications. Tailored protocols that reduce exposure & radiation dosage and a more strictly adhered to follow-up regime that utilizes Ultrasonography and/or MRI (where available) may be the answer.
I’ve been thinking about this one. If ultrasound is a good but technically demanding examination for IBD , perhaps it’s worth spending time learning to do it well. It’s nicer and cheaper for the patient.
Thanks for the comment Dr. Peng.
The problem with utlrasound is not just that it’s technically demanding. Even the most proficient sonographer would never be sure if s/he picked up all the findings in a given case however optimal be the patient. CT (and MRI, with reservations) give an operator and modality independent full picture view.
I agree, but we so often have negative barium follow-through studies for patients with vague symptoms that I have been trying to figure out whether a careful ultrasound would suffice in some cases, given that you can often see bowel wall thickening on US.
On a related topic I thought it was interesting that in this recent article the authors found no significant difference in sensitivity between CT, MT or BaFT for detection of terminal ileitis.
http://radiology.rsnajnls.org/cgi/content/abstract/2513081184v1
Peng