Gil-Sun Hong MD, Presenter: Nothing to Disclose

Seong Ho Park MD, Abstract Co-Author: Research Grant, DONGKOOK Pharmaceutical Co, Ltd Research Grant, General Electric Company

Bohyun Kim MD, Abstract Co-Author: Nothing to Disclose

Ju Hee Lee MD, Abstract Co-Author: Nothing to Disclose

Jin Cheon Kim, Abstract Co-Author: Nothing to Disclose

Chang Sik Yu, Abstract Co-Author: Nothing to Disclose

To determine if the colonic bubbles observed on CT colonography (CTC) performed with cathartic preparation and oral iohexol for fecal/fluid tagging, could be prevented by simethicone.

IRB approval was obtained. This prospective, randomized, controlled trial compared 80 adults suspected of having colonic neoplasia who had been randomly assigned in a 1:1 ratio to the control (M:F, 23:17; 63 years±11.6) and intervention (M:F, 22:18; 60 years±11.8) groups. Patients underwent CTC after cleansing with 4 L of polyethylene glycol, tagging with 50 mL of 350 mgI/mL oral iohexol, and without (control) or with (intervention) oral administration of 200 mg of simethicone. Thirty-eight control and 37 intervention patients subsequently underwent colonoscopy and/or surgery which served as the reference standards for the CTC accuracy. The primary endpoint was a per-patient score intended to measure the amount of colonic bubbles, ranging 0 (no bubbles) to 5 (the largest amount). The secondary endpoints included the per-lesion sensitivity, accounted for clustered data and lesion diameter, and per-patient specificity of CTC for adenomas and carcinomas 6 mm or greater.

Randomization was effective and the patient and lesion characteristics were comparable between the two groups except for the presence of six flat colonic lesions only in the control group. The per-patient score of the amount of colonic bubbles was significantly smaller in the intervention, i.e. with simethicone, group than in the control group: mean score±SD of 0.0±0.1 versus 1.2±0.8, respectively (P<.001). The CTC sensitivity and specificity did not differ significantly between the control and the intervention groups (78% [126/162] or 88% [126/144] when flat lesions were excluded versus 91% [131/144], P=.247 or .325; and 96% [26/27] versus 89% [24/27], P=.795, respectively).

Colonic bubbles noted on CTC after cathartic preparation and fecal/fluid tagging using iohexol, can be successfully prevented by adding simethicone to the preparation.

CTC can be performed successfully and more conveniently for patients using iohexol for fecal/fluid tagging and by adding simethicone (which is a highly economical, safety-proven, easy-to-take, anti-foaming medicine) to the preparation in order to prevent colonic bubbles associated with iohexol.

Hong, G, Park, S, Kim, B, Lee, J, Kim, J, Yu, C, Simethicone Used to Prevent Colonic Bubbles on CT Colonography Performed with Iohexol for Fecal/fluid Tagging: A Randomized Controlled Trial.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14004523.html