Meta-Analyses on Quantitative ICG Perfusion Parameters for Predicting Anastomotic Leakage in Colorectal Surgery
Yes, multiple recent meta-analyses exist examining the diagnostic test accuracy of quantitative ICG perfusion parameters for predicting anastomotic leakage in colorectal surgery, with the most comprehensive and recent being published in 2026.
Most Recent and Highest Quality Evidence
The 2026 systematic review and trial sequential analysis by Surgery journal 1 represents the most robust meta-analysis to date, analyzing 7 randomized controlled trials with 4,636 patients. This study demonstrated that ICG fluorescence angiography significantly reduced anastomotic leakage rates (risk ratio 0.69,95% CI 0.58-0.82, p<0.001) with negligible heterogeneity (I²=0%). Critically, trial sequential analysis confirmed that the required information size has been reached for the overall analysis, meaning we now have sufficient evidence to draw definitive conclusions about ICG's protective effect.
A concurrent 2026 meta-analysis in Surgical Endoscopy 2 analyzed 10 RCTs with 4,885 patients and found similar results (OR=0.64, p<0.0001, high evidence quality), with particular benefit in left colon (p=0.003) and rectal resections (p=0.0002), but no difference in right colon surgery (p=0.94).
Key Findings Across Meta-Analyses
Leak Reduction by Anatomic Location
- Left-sided and rectal anastomoses: 31-47% reduction in leak rates 2, 1, 3
- Right colon: No significant benefit demonstrated 2
- Low colorectal/coloanal anastomoses: 37% reduction (RR 0.63,95% CI 0.51-0.76) 1
Leak Severity Classification
ICG reduces both:
- Grade A leaks (subclinical): 46-69% reduction 1, 4
- Grade B+C leaks (clinically significant): 33% reduction 1
Surgical Decision Impact
ICG assessment prompted intraoperative surgical strategy changes in 7.5-fold more cases compared to white light assessment (OR=7.50, p=0.02) 2, though this did not translate to differences in reoperation rates.
Critical Limitations Identified
The major caveat across all meta-analyses is the absence of standardized, objective quantitative criteria for ICG interpretation 3. Current studies rely on subjective visual assessment rather than validated quantitative perfusion parameters (e.g., time to peak fluorescence, slope of fluorescence curve, fluorescence intensity thresholds). This represents a fundamental gap between the question asked and the evidence available—while meta-analyses exist on ICG use broadly, none specifically validate quantitative perfusion parameters as diagnostic tests with defined sensitivity/specificity thresholds.
The 2025 World Journal of Surgical Oncology meta-analysis 3 explicitly identifies this as a "critical barrier to achieving reproducible clinical benefits," noting that patient-specific factors like cardiovascular disease and obesity affect ICG kinetics but are not accounted for in current protocols.
Guideline Context
The 2022 WSES guidelines on bowel injury 5 acknowledge that "the use of indocyanine green fluorescent intraoperatively in trauma settings to predict anastomotic leak is a very new concept. Little data exists with no large prospective studies; however, case series appear promising and demonstrate usefulness in assessing bowel integrity."
The 2018 WSES guidelines on colorectal cancer emergencies 6 note that "evidence exists regarding the validity of the assessment of the anastomotic blood supply using intraoperative near-infrared indocyanine green," though these guidelines predate the definitive RCT evidence.
Clinical Implementation
For left-sided and rectal resections, ICG fluorescence angiography should be used to reduce anastomotic leak rates based on moderate-to-high certainty evidence 2, 1, 3. However, the technique currently functions as a "rule-out tool to exclude clearly unsafe conduit segments" 7 rather than providing validated quantitative diagnostic thresholds.
The 2026 Diagnostics study 8 represents emerging work attempting to establish quantitative frameworks by combining hyperspectral imaging with ICG, but this remains investigational and not yet validated for clinical decision-making.
Bottom Line
Multiple high-quality meta-analyses confirm ICG reduces anastomotic leaks in colorectal surgery, but none validate specific quantitative perfusion parameters (time-to-peak, slope, intensity thresholds) as diagnostic tests with established accuracy metrics. The evidence supports ICG use based on qualitative visual assessment, not quantitative diagnostic test accuracy. Future research must establish standardized quantitative criteria accounting for patient-specific variables before ICG can function as a true diagnostic test rather than a subjective intraoperative adjunct.