P3836 - An Updated Analysis of a Multicenter RCT to Address the Unexplored Issue of Cap Type and Regional Differences in ADR in Cap-Assisted Water Exchange Colonoscopy

Felix Leung, MD, FACG¹, Angshuman Saha, PhD^2
1VA Sepulveda Ambulatory Care Center, Northridge, CA; ²David Geffen School of Medicine at UCLA, Los Angeles, CA

Introduction: We reported the primary outcome of overall ADR of an RCT at the 2024 DDW. When coupled with WE, Daisycuff^TM (DC), Endocuff Vision (ECV), but not straight cap (SC), increased overall ADR, compared with WE alone (all P< 0.05, vs. no cap). An insightful question which we were unable to answer after the presentation was whether there was regional (proximal vs. distal) ADR differences based on cap type. We subsequently performed the proper analysis which is presented here.

Methods: At 7 international sites, all subjects (n=1380) were examined with WE. SC was the standard 4 mm cap (Olympus). DC (Vizballoon) had 10 “petals” around the ring. During insertion and withdrawal, the colon was pleated on the instrument shaft by one DC at the tip and one at the 20 cm mark. ECV (Olympus) had a single row of eight flexible protruding arms. By pressing against the folds, all caps placed at the tip could enhance the view of the oral side of folds. (ClinicalTrial.gov NCT03566615)

Results: Logistic regression analyses (Table 1) revealed the following findings not addressed at the 2024 DDW meeting. In the proximal colon, DC had the highest ADR (41.9%) vs. no cap (33%) (P=0.024); while ECV and SC had no significant impact. In the distal colon, ECV showed higher ADR (vs. no cap) (38.7% vs. 23.1%, P=0.0002); and SC had a significant but small effect (28.9% vs. 23.1%, P=0.0456).

Discussion: Other than donating the DC the manufacturer did not intervene in the study (supported solely by ASGE). It was well established that WE increased proximal colon ADR by enhancing bowel cleanliness. The effect of DC with WE in increasing regional ADR was most notable in the proximal colon. Presumably in addition to increased fold exposure by the DC at the tip, the DC at the 20 cm mark assisted in dispersing the “spring effect” when the pleated colon was held at two separate points (tip and 20 cm) along the shaft. On withdrawal, there was less “bowstring instability”. The visualization of the oral side of the folds occurred in a more controlled fashion with less negative impact due to “fly-off” compared with no cap, SC or ECV. In the distal colon, the effect of ECV in increasing regional ADR was most prominent; and the impact of SC albeit significant was small. Since ICs clustered in the proximal colon, the novel effect of DC with WE in significantly increasing proximal colon ADR deserves to be highlighted at the ACG meeting as an approach to prevent proximal colon ICs.


Disclosures:


Felix Leung, MD, FACG¹, Angshuman Saha, PhD². P3836 - An Updated Analysis of a Multicenter RCT to Address the Unexplored Issue of Cap Type and Regional Differences in ADR in Cap-Assisted Water Exchange Colonoscopy, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.