Indocyanine green fluorescence to prevent anastomotic leak in colorectal surgery: an updated systematic review and meta-analysis on randomized controlled trials

Background: In light of the recent publication of two multicentric controlled trials, this systematic review and meta-analysis aims to update the evidence of the efficacy of Indocyanine Green fluorescence angiography in preventing the risk of anastomotic leak after colorectal surgery. Methods: MEDLINE, EMBASE, and CENTRAL databases were searched for randomized controlled trials using relevant keywords from 2015 until September 2025. The outcomes were the overall rate of anastomotic leaks, the rate of reoperations, and the rate of intraoperative surgical strategy changes. Results: Ten randomized controlled trials were selected, including 4.885 patients, 2.432 (49.7%) who received intraoperative ICG assessment and 2.453 (50.3%) who underwent standard white light assessment. The studies displayed a moderate risk of bias and were included in the meta-analysis. The ICG group showed a reduced rate of anastomotic leak (OR = 0.64; p < 0.0001; high evidence) compared with the standard dressing group and a higher rate of changes in surgical strategy (OR = 7.50; p = 0.02; moderate evidence), while no difference was found in the rate of reoperations (OR = 0.94; p = 0.64; moderate evidence). A subgroup analysis showed reduced anastomotic leak rates in left colon (p = 0.003) and rectal resection (p = 0.0002) and no differences after right colon surgery (p = 0.94). Conclusions: This systematic review and meta-analysis supports the use of ICG to reduce the anastomotic leak rate in colorectal surgery, in particular in left-sided and rectal resections.