Accuracy of Colonoscopic Visualization


The objective of this study is to evaluate the accuracy of pre-operative colonoscopic localization of colonic lesions. Localization of the colonic lesion plays a key role in determining the type of operation a patient may require. Inaccurate localization may result in removal of the wrong segment of colon and/or a change in the operation performed.


A retrospective review of patients who had a colon resection by a single surgeon after pre-operative colonoscopic localization from 1991 to 2008 was performed. A comparison of the preoperative colonoscopic and final intraoperative localization was made. Clinical and demographic information was gathered to determine accuracy rates overall and by colon region, and to attempt to identify predictive factors.


374 patients were included in this study. 184 (49%) were male. The mean age was 61.6 years. 362 patients (97%) underwent colon resection for colorectal cancer. 15 patients (4%) were found to have non-concordant colonoscopic and intra-operative findings. 14 of 15 (93%) were being resected for colorectal cancer, and 1 for inflammatory bowel disease. 7 (47%) lesions were inaccurately localized in the sigmoid colon, 4 (27%) in the descending colon, 2 (13%) in the ascending colon, 1 (7%) in the rectum and 1 (7%) lesion was not visualized by colonoscopy preoperatively. 11 of the 15 patients (73%) with non-concordant localization had a modification of their planned operative procedure. Due to non-concordant intraoperative localization, 10 patients underwent a different segmental colectomy than planned preoperatively, and 1 patient underwent an extended resection.


Preoperative colonoscopic localization of colorectal lesions was reasonably accurate (96%) in this large series of patients undergoing colon resection. The majority of inaccurately identified lesions occur in the sigmoid and descending colon. Incorrect localization, even though not terribly common, can result in significant changes in intraoperative plan and ultimate outcome. Therefore even though this is not common, every effort should be made to localize the lesion before surgery, especially when thought to be in the left or sigmoid colon, to reduce the need for intraoperative localization efforts, for an intraoperative change in procedure, and for a surprise for the patient after surgery.

Session: Poster

Program Number: P170

View Poster

« Return to SAGES 2009 abstract archive