Intraprocedural Cleansing for Screening Colonoscopy: Avoiding Brownouts

Adequate bowel preparation has long been considered an essential prerequisite for successful endoscopic procedures since residual feces can obscure mucosal pathology [1], particularly flat polyps termed non-polypoid colorectal neoplasms (NP-CRNs) [2]. Overall, NP-CRNs are more likely to harbor carcinoma (odds ratio *10) than polypoid lesions, irrespective of size [3]. With regard to shape, depressed-type NP-CRNs are associated with a 33 % risk of malignancy, which is the highest of all polyp types [3]. Modifiable factors with an impact on adenoma detection rate (ADR) include increasing the length of time used for withdrawal inspection, looking behind folds, and retroflex examination for the detection of NP-CRNs. There is current emphasis regarding improving bowel cleanliness which improves recognition and facilitates complete resection of NP-CRNs, sessile serrated polyps, and advanced adenomas [4]. In this issue of the Digestive Diseases and Sciences, Oh et al. [5] evaluated the impact of the quality of bowel cleansing on detection of NP-CRNs. In a retrospective analysis of screening colonoscopy performed by seven board-certified attending gastroenterologists at one academic teaching hospital, patients underwent recommended split-dose bowel preparation, with endoscopic removal of fecal debris and retained fluid accomplished by forceful irrigation and suction, prior to rating bowel preparation quality. In 6097 asymptomatic, average-risk screening examinations, the preparation quality was rated as adequate (excellent or good) in 5224 (85.7 %), fair in 615 (10.1 %), and poor in 258 (4.2 %) patients. Efforts to improve the preparation quality increased the detection rate of NPCRNs, improving the efficacy of screening colonoscopies. Interestingly, the split-dose bowel preparation, formerly lauded for its efficacy on the basis of clinical trial data, was less perfect in real-life clinical settings, necessitating intraprocedural cleansing. In the study by Oh et al. [5], the primary outcome was a comparison of the adenoma detection rate (ADR) for nonpolypoid lesions according to quality of bowel preparation. The overall ADR of non-polypoid pathology, 12.3 % (747/ 6097) of all colonoscopies, significantly differed between participating endoscopists. The ADR for non-polypoid pathology was significantly lower if preparation was rated as fair or poor quality compared with the ADR associated with adequate preparation. Furthermore, detection of\ 1 cm in lesions in the proximal colon was significantly lower with poor preparation than with adequate preparation. Of 5946 polyps detected in the study population, 4847 were histologically confirmed as adenomas (84.7 %) or serrated polyps (15.3 %). More than half were located in the proximal colon (2590/4847), most were of \1 cm (4570/4847), and almost all were flat (0-IIa or 0-IIb) lesions (4843/4847). The proportion of NP-CRNs among all neoplastic lesions was 40.5 % (1962/4847), with the proportion of advanced neoplasms among NP-CRNs 3.5 % (68/1962). Although the report is limited by its retrospective and single-site design, the study has several strengths: It involved a large patient population and also focused on NPCRNs which have recently assumed greater importance due to their increased malignant potential compared with & Felix W. Leung felix.leung@va.gov