Safety and Outcomes of Same-day CT Colonography After Incomplete Optical Colonoscopy - A Single Center Experience

Abstract

Purpose: CT colonography has proven a useful tool to complete colon cancer screening in patients when optical colonoscopy fails. Performed on the same day, CT colonography obviates the need for a second bowel preparation and medical appointment. However, concern has been raised over the safety of performing back-to-back procedures given the need for a second air insufflation. The aim of this study was to evaluate the safety and outcome of same-day CT colonography after an incomplete colonoscopy at a community hospital. Methods: A retrospective analysis identified 244 consecutive patients who underwent CT colonography between June 2006 and May 2011 for colon cancer screening. Variables including patient demographics, test findings, and safety were evaluated in the cohort of patients who underwent same-day CT colonography for failed optical colonoscopy. Results: The total number of colonoscopies performed during the study interval was 30,741. There was one incomplete colonoscopy for every 232 performed. Following incomplete optical colonoscopy, 132 patients underwent same-day CT colonography. The study group was composed of 85 women and 47 men. The median age was 64. The most common indication for colonoscopy was colorectal cancer screening (49, 37%) followed by polyp surveillance (22, 17%). Prior abdominal surgeries were noted in 25 patients (19%). The most common reasons for an incomplete colonoscopy were bowel looping (52, 40%) and pain (26, 20%). The most frequent location of exam termination was at the splenic or hepatic flexures (23, 17% each). CT colonography revealed 3 polyps of greater than 10 mm, 23 polyps of 5 to 10 mm and 41 polyps of less than 5 mm. Thirty follow-up studies including colonoscopy and surgery with biopsy were performed and confirmed 4 tubular adenomas, one tubulovillous adenocarcinoma in situ with severe dysplasia and one adenocarcinoma. There were no bowel perforations or other complications reported and no patient required overnight admission. The most common extracolonic finding was renal calculi. Conclusion: Same-day CT colonography performed after incomplete optical colonoscopy is a safe strategy to complete colorectal cancer screening without requiring a second bowel preparation or medical visit.