The aim of this study was to examine the efficacy of IV
Buscopan as a muscle relaxant in CT colonography in terms of colonic distension and
polyp detection, and to determine its particular efficacy in patients with
diverticular disease. Seventy-three consecutive patients were randomised to receive IV
Buscopan or no muscle relaxant prior to CT colonography. CT colonography was performed using a Siemens Somatom 4-detector multislice CT scanner. The following parameters were recorded: degree of colonic distension using a 4-point scale; diagnostic adequacy of colonic distension; presence or absence of
diverticular disease; and presence of
colonic polyps. Accuracy of
polyp detection was assessed using subsequent conventional colonoscopy as a gold standard. There was no significant difference between the two groups in the number of segments that were deemed to be optimally or adequately distended (p=0.37). Although IV
Buscopan did improve distension of certain segments, this effect was not sufficient to improve the number of diagnostically adequate studies in the
Buscopan group (p=0.14). In patients with
diverticular disease, IV
Buscopan did not have any significant effect on segments affected by
diverticulosis but was associated with an improvement in distension of more proximal segments. There was no significant difference between the two groups in terms of
polyp detection (p=0.34). The addition of prone scanning to supine scanning was found to be the most useful technique for maximising colonic distension. Intravenous
Buscopan at CT colonography does not improve the overall adequacy of colonic distension nor the accuracy of
polyp detection. In patients with sigmoid
diverticular disease IV
Buscopan improves distension of more proximal colonic segments and may be useful in selected cases, but our results do not support its routine use for CT colonography.