P1303 - Incremental Yield of Adenoma Detection with High-Definition I-Scan Colonoscopy Compared to White Light Endoscopy – A Meta-Analysis of Prospective Studies and Randomized Controlled Trials
University of Texas Health Science Center at Houston Houston, TX, United States
Faisal Ali, MD1, Nirav Thosani, MD, MHA2 1University of Texas Health Science Center at Houston, Chicago, IL; 2University of Texas Health Science Center, Houston, TX
Introduction: I-Scan image post-processing technology may improve the detection of adenomatous polyps. The incremental yield of I-Scan compared to standard high-definition white light endoscopy (WLE) has not been summarized thoroughly.
Methods: A systematic search of Medline and Embase from inception-May 2021 was conducted to identify prospective studies and randomized-trials comparing I-Scan to WLE for detection of adenomas < 10mm in size. The primary measure of incremental yield of adenoma detection was extrapolated from the difference in proportion of adenomatous polyps/patients detected by I-Scan versus WLE with their corresponding 95% confidence intervals. Each polyp was regarded as a patient for the purpose for our analyses. Diagnostic test performance was analyzed and used to compute number needed to detect as a secondary measure of incremental yield of I-Scan.
Results: Screening of 1508 articles yielded 10 studies (2505 patients/polyps in I-Scan, 2091 patients/polyps in WLE arm). The pooled adenoma detection rate was 54% (31-78%) with I-Scan and 42% (24-59%) with WLE use. I-Scan led to a 10% increase in yield of adenoma detection (risk difference (RD): 0.10; 0.05-0.16; I2 72.63%), with 11% increase in subgroup analysis of prospective studies (2-20%; I2 63.61%) and 10% in randomized-trials (2-17%; I2 71.01%). Upon stratifying studies by year of publication, reports published ≥2015 showed a 13% increase in yield of adenoma detection with I-Scan use, though with a wide confidence interval (RD 0.13; -0.01-0.26; I2 72.99%), compared to 9% in reports published < 2015 (RD 0.09; 0.03-0.15; I2 72.06%). Influence analysis revealed that none of the studies had an overdue impact on the final analysis. Subgroup analysis of diminutive polyps (< 5mm) showed a 7% increase in yield of adenoma detection with I-Scan use (RD 0.07; 0.01-0.13; I2 76.88%).
The pooled sensitivity and specificity of I-Scan in characterizing polyps was 87% (71-95%) and 86% (80-90%) and that of WLE was 77% (58-90%) and 79% (56-91%), respectively. The number needed to detect one additional adenomatous polyp with I-Scan use was 1.4.
Discussion: I-Scan increases the yield of adenoma detection by 10% (7% in diminutive polyps) compared to WLE based on a meta-analysis of prospective studies and randomized-trials, with a low number needed to detect one additional adenomatous polyp, albeit with notable heterogeneity in the pooled data. Our findings may be used to advocate for the use of I-SCAN to enhance detection of adenomas < 10 mm in size.
Figure: Forrest plots of difference in detection of adenomatous polyps <10 mm in size and diminutive (<5 mm) adenomatous polyps.
Disclosures:
Faisal Ali indicated no relevant financial relationships.
Nirav Thosani: Boston scientific – Consultant. Pentax America – Consultant.
Faisal Ali, MD1, Nirav Thosani, MD, MHA2. P1303 - Incremental Yield of Adenoma Detection with High-Definition I-Scan Colonoscopy Compared to White Light Endoscopy – A Meta-Analysis of Prospective Studies and Randomized Controlled Trials, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.
