Comparison of adenoma detection rate between three-dimensional and standard colonoscopy: a multicenter randomized controlled trial.

Background: Improvement in adenoma detection rates (ADRs) effectively reduces the incidence of colorectal cancer. In a simulation study, three-dimensional (3D) colonoscopy provided more anatomical details than standard two-dimensional (2D) colonoscopy and improved ADR. We compared ADRs between 2D and 3D colonoscopy.

Methods: In this multicenter randomized controlled trial, participants aged ≥40 years undergoing colonoscopy for screening, surveillance, or symptoms between February 2022 and June 2023 were randomized 1:1 into 2D or 3D groups. The primary outcome was ADR. Secondary outcomes included detection rates for flat adenomas, right-sided adenomas, proximal adenomas, advanced adenomas, and sessile serrated lesions (SSLs).

Results: Of 348 participants recruited, data from 158 (2D group) and 160 (3D group) were analyzed. Mucosa inspection time was comparable between the 3D (9.8 [SD 2.6] minutes) and 2D (9.4 [SD 3.1] minutes) groups (P = 0.21). Compared with the 2D group, the 3D group had a significantly higher ADR (53.1% vs. 38.6%; difference 14.5% [95%CI 3.7 to 25.4]; P = 0.009), and higher detection rates for flat adenomas (35.0% vs. 21.5%; difference 13.5% [95%CI 3.7 to 23.3]; P = 0.008), right-sided adenomas (26.3% vs. 15.2%; difference 11.1% [95%CI 2.2 to 19.9]; P = 0.02), proximal adenomas (38.1% vs. 23.4%; difference 14.7% [95%CI 4.7 to 24.7]; P = 0.005), and adenomas sized 5–9 mm (45.0% vs. 31.0%; difference 14.0% [95%CI 3.4 to 24.5]; P = 0.01). There was no difference in detection rates for SSLs or advanced adenomas.

Conclusion: 3D colonoscopy improved adenoma detection without significantly increasing the mucosa inspection time.