A blinded prospective trial of low-residue versus normal diet in preparation for barium enema.

This study was undertaken to determine whether the omission of a low-residue diet in the days leading up to barium enema resulted in poorer bowel preparation. 300 patients were randomized prospectively into one of two groups. One group followed a low-residue diet for the 3 days leading up to the study, the other continued their usual diet. Both groups had two doses of "Picolax" the day before the study. 17 patients did not attend, and a further two patients were excluded, leaving 281 patients for prospective study. The subsequent investigation was assessed blind by a consultant radiologist and graded for faecal residue, mucosal coating and diagnostic quality. No statistically significant difference was found between the two groups for amount of faecal residue (p < 0.25), mucosal coating (p < 0.25) or diagnostic quality (p < 0.5). We conclude, therefore, that a preliminary low-residue diet is unnecessary in the preparation of patients for barium enema. Patients should continue with their usual diet up to the day prior to the test and then have standard purgative preparation.