title: Simethicone to prevent colonic bubbles during CT colonography performed with polyethylene glycol lavage and iohexol tagging: a randomized clinical trial.
abstract: OBJECTIVE
  The purpose of this study was to determine whether the occurrence of numerous colonic bubbles during CT colonography (CTC) performed with polyethylene glycol cleansing and oral iohexol fecal/fluid tagging could be prevented by use of simethicone.
  
  
  METHODS
  Adults with suspected colonic neoplasia who had been randomly assigned to control and simethicone intervention groups underwent CTC after cleansing with 4 L of polyethylene glycol, tagging with 50 mL of 350 mg I/mL oral iohexol, and without (control) or with (intervention) oral administration of 200 mg of simethicone. Colonic segments in the control and intervention groups were evaluated for amount of colonic bubbles during CTC. A 6-point grading system was used in which 0 indicated no bubbles and 5 indicated that more than three fourths of the air-distended mucosa was covered with bubbles. The primary endpoint was a per-patient colonic bubble grade, derived as an average of the segmental grades.
  
  
  RESULTS
  Eighty adults with suspected colonic neoplasia were randomly assigned to the control (40 patients) and simethicone intervention (40 patients) groups. A total of 659 colonic segments in the control group and 689 segments in the intervention group were evaluated for amount of colonic bubbles during CTC. The per-patient colonic bubble score was significantly lower in the simethicone intervention group than in the control group. The mean score was 0.0±0.1 (SD) versus 1.2±0.8 (p<0.001; 95% CI for the mean difference, -1.4 to -1.0). In the intervention group, 673 (97.7%) segments were grade 0, and 16 (2.3%) were grade 1. In contrast, in the control group, 226 (34.3%) segments were grade 0; 173 (26.3%), grade 1; 175 (26.6%), grade 2; 45 (6.8%), grade 3; 23 (3.5%), grade 4; and 17 (2.6%), grade 5.
  
  
  CONCLUSIONS
  The colonic bubbles associated with fecal/fluid tagging with iohexol can be successfully prevented by adding simethicone to the colonic preparation.
authors: 1 Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Korea.
authors: Gil-Sun
authors: GS
authors: Hong
authors: Seong Ho
authors: SH
authors: Park
authors: Bohyun
authors: B
authors: Kim
authors: Ju Hee
authors: JH
authors: Lee
authors: Jin Cheon
authors: JC
authors: Kim
authors: Chang Sik
authors: CS
authors: Yu
authors: Seunghee
authors: S
authors: Baek
authors: Jong Seok
authors: JS
authors: Lee
authors: Hyun Jin
authors: HJ
authors: Kim
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000934:Antifoaming Agents / Q000494:pharmacology*; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic; D003113:Colonoscopy; D003287:Contrast Media / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007472:Iohexol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000494:pharmacology*; D011446:Prospective Studies; D012841:Simethicone / Q000008:administration & dosage / Q000494:pharmacology*; D007507:Therapeutic Irrigation / Q000379:methods
chemical_list: D000934:Antifoaming Agents; D003287:Contrast Media; D011092:Polyethylene Glycols; D007472:Iohexol; D012841:Simethicone
keywords: CT colonography; bubbles; iohexol; simethicone; tagging