Mo1077 Clinical Efficacy of Same Day CT Colonography Following Incomplete Colonoscopy

Abstract

Background: Colonoscopy is the preferred screening method for colorectal cancer (CRC) but may be incomplete in 4% to 25% of cases. CT colonography (CTC) is an adjunct to evaluate the colon after an incomplete colonoscopy (IC). No study has focused on same day CTC after an IC. Our primary aim was to determine the yield of same day CTC after IC. Methods: Our institution has the capability to perform same day CTC in patients with an incomplete colonoscopy. This was a retrospective review of all CTC done immediately following IC from January 2008 to December 2012. 198 CTC met inclusion criteria. Descriptive statistics were used. Results: Of 198 patients with IC and CTC 50 patients had 61 intracolonic findings. 23/50 (46%) were screening procedures, 1/50 (2%) high risk screening, 17/50 (34%) had a diagnostic colonoscopy and 9/50 (18%) surveillance colonoscopy. 10/50 patients had 12 findings on CTC on areas that were not reached by incomplete colonoscopy. 6 of these 10 patients had a follow up intervention: 2 had retrograde double balloon enteroscopy and 4 had colonoscopies. 3 findings correlated with CTC (1 ascending colon adenocarcinoma and 2 polyps) and 3 did not ( normal colonoscopy/DBE). 40 patients had 49 colonic findings on CTC on areas reached but not described during IC. 19/49 (39%) findings were not described during the initial colonoscopy. Only 6 of these 40 pts had a repeat colonoscopy. 9 findings did not correlate with subsequent complete colonoscopy. Only 1 CTC finding correlated with repeat colonoscopy. There were 30 colonic findings on CTC in areas that were reached and described during the incomplete colonoscopy. Nineteen were sigmoid diverticular strictures with no additional findings in the rest of the colon, 10 were diverticulosis of the sigmoid and 1 ascending colon adenocarcinoma with no synchronous lesions. Conclusions: Same day CTC can be of added value in patients with incomplete colonoscopy. Potential benefits include no need to repeat bowel cleansing and no extra day lost from work. Our data showed that correlation of findings by CTC in areas not visualized by incomplete colonoscopy was poor as 50% of patients had CTC abnormalities which did not correlate with a repeat colonoscopy. When CTC described an abnormality in an area already reached but not described during IC correlation was also poor as only one patient had correlation between CTC and repeat colonoscopy. When CTC reported the same findings described during IC correlation was 100%. More data on the efficacy and cost-effectiveness of same day CTC compared to repeating a colonoscopy or maybe performing a retrograde overtube assisted enteroscopy is needed to determine which effort is worthwhile.