Effect of add-on devices with projections on screening colonoscopy: a systematic review and meta-analysis

BACKGROUND: Add-on devices with projections, e.g., Endocuff, Endocuff Vision, EndoRings, and Wingcap, placed on the distal tip of the colonoscope promise to improve the detection of precancerous lesions. We performed a meta-analysis to evaluate the performance of these devices exclusively among individuals undergoing colonoscopy for screening purpose. METHODS: A computerized literature search was performed across MEDLINE and Cochrane Library databases for randomized controlled trials that compared standard colonoscopy (SC) to procedures using add-on devices. The primary outcome was adenoma detection rate (ADR), while secondary outcomes included polyp detection rate (PDR), advanced ADR (AADR), and sessile serrated lesion detection rate (SSLDR). The effect size on study outcomes was calculated using a random-effects model and presented as the risk ratio (RR) and 95% confidence interval (CI). RESULTS: Seven studies enrolling a total of 5785 patients were included. The use of add-on-devices with projections was associated with a higher ADR compared to SC: 45.9% vs. 41.1%; RR 1.18, 95%CI 1.02-1.37; P=0.03; I(2)=79%. Although PDR was higher in screening colonoscopies assisted by add-on devices as compared to SC, the difference failed to reach significance: 55.1% vs. 50.8%; RR 1.10, 95%CI 0.96-1.26; P=0.17; I(2)=75%. No difference was found between procedures assisted by add-on devices with projections and SC colonoscopies in terms of AADR (18.5% vs. 17.6%; RR 1.00, 95%CI 0.79-1.27; P=0.98; I(2)=56%) or SSLDR (6.8% vs. 5.8%; RR 1.17, 95%CI 0.95-1.44; P=0.15; I(2)=0%). CONCLUSION: Colonoscopy assisted by add-on devices with projections achieves a better ADR compared to SC among individuals undergoing screening for bowel cancer.