Use of intraoperative ICG fluorescence angiography to reduce anastomotic leak in left‐sided colorectal resections: A systematic review and meta‐analysis of RCTs

Abstract Aim Anastomotic leak remains a serious complication after left‐sided colorectal resection with substantial morbidity, mortality and healthcare costs. This systematic review and meta‐analysis evaluated whether intraoperative indocyanine green (ICG) fluorescence angiography reduces anastomotic leak rates in patients undergoing left‐sided colorectal resections. Methods A systematic search of major databases and trial registries was conducted for RCTs comparing ICG angiography with standard visual assessment in adults undergoing elective left‐sided colorectal resection. The primary outcomes were overall and clinically significant (ISGRC Grade B/C) anastomotic leak. Risk ratios (RRs) were pooled using a random‐effects model. Risk of bias was assessed with the Cochrane ROB2 tool. Results Ten trials involving 3,772 patients were included. ICG fluorescence angiography, compared to control, reduced overall anastomotic leak (RR 0.62, 95% CI 0.53–0.73; I 2 = 0%; prediction interval 0.50–0.77) and clinically significant leak (RR 0.66, 95% CI 0.51–0.85; I 2 = 0%). Assuming a 10% baseline leak rate, ICG prevents one leak per 27 patients treated. Subgroup analysis showed benefit even when ICG did not prompt surgical plan modification (RR 0.67, 95% CI 0.50–0.90). Between‐study heterogeneity was negligible across all analyses. ICG use did not prolong operating time and has reduced postoperative complications (RR 0.88, 95% CI 0.73–1.05). Conclusion Intraoperative ICG fluorescence angiography significantly reduces anastomotic leak rates after left‐sided colorectal resection, with consistent benefit across diverse surgical settings. The technology is practical and does not prolong operating time. ICG angiography should be considered a valuable adjunct in left‐sided colorectal resections.