Three-day regimen improves faecal tagging for minimal preparation CT examination of the colon.

This study set out to determine whether extending the length of oral contrast administration in minimal preparation CT of the colon improves faecal tagging. Two cohorts of 50 patients each were compared, one with a 2-day the other with a 3-day faecal tagging regimen. The degree of faecal tagging was graded by two blinded observers. The 3-day regimen showed significantly better tagging in the rectum and sigmoid colon (p = 0.006 and p = 0.009, respectively, using the Mann-Whitney test). The percentage of patients who had faecal tagging in the sigmoid colon graded as "complete" was 64% for the 3-day regimen as opposed to 34% for the 2-day regimen. The corresponding percentages for the rectum were 64% for the 3-day regimen and 36% for the 2-day regimen. Extending the length of oral contrast administration from 2 to 3 days significantly improves the quality of faecal tagging in the rectum and sigmoid colon.