Indocyanine Green Fluorescence Imaging for Colorectal Surgery: A Health Technology Assessment

Both malignant and benign conditions may require colorectal surgery. Anastomotic leak is a serious potential complication, and assessing tissue perfusion at the planned site of anastomosis is critical to try to prevent leaks. The approaches used by surgeons to assess anastomotic integrity and tissue perfusion involve visual assessment of the planned resection area. Indocyanine green fluorescence imaging (ICGFI) is a technology that involves the use of a fluorescent dye and a near-infrared imaging system to allow surgeons to visualize tissue perfusion intraoperatively in real time. We conducted a health technology assessment of ICGFI in colorectal surgery, which included an evaluation of effectiveness, cost-effectiveness, the budget impact of publicly funding ICGFI for the assessment of anastomotic perfusion during colorectal surgery, and the experiences of patients undergoing colorectal cancer surgery.

We performed a systematic review of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk-of-Bias Tool for randomized controlled trials (RCTs) and the Risk-of-Bias Assessment Tool for Nonrandomized Studies (RoBANS) for nonrandomized studies. We assessed the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature search and conducted a cost-effectiveness analysis comparing ICGFI with visual assessment alone for the visualization of anastomotic perfusion during colorectal surgery from a public payer perspective. We also analyzed the budget impact of publicly funding ICGFI for colorectal surgery in Ontario. To contextualize the potential value of publicly funding ICGFI for colorectal surgery, we summarized a qualitative literature rapid review conducted by the Canadian Agency for Drugs and Technologies in Health (now Canada's Drug Agency).

We included 6 RCTs and 13 nonrandomized studies in the clinical evidence review. Compared with visual assessment alone, the addition of ICGFI to assess anastomotic perfusion during colorectal surgery reduced anastomotic leaks (GRADE: Low) and reoperations (GRADE: Low) and slightly reduced sepsis, but the evidence for the latter is very uncertain (GRADE: Very low to Low). ICGFI appeared to have little to no effect on hospital readmissions (GRADE: Low) or length of stay (GRADE: Low to Moderate), and its effect on mortality is very uncertain (GRADE: Very low). Our primary economic evaluation found that ICGFI is more effective and less costly than visual assessment alone and is highly likely to be cost-effective at the commonly used willingness-to-pay values of $50,000 and $100,000 per quality-adjusted life-year (QALY). The use of ICGFI could prevent 22 major anastomotic leaks per 1,000 patients undergoing colorectal surgery with anastomosis. With ICGFI, 45 patients would need to be treated to prevent an additional major anastomotic leak. Publicly funding ICGFI to assess anastomotic perfusion in colorectal surgery in Ontario would lead to an annual budget impact ranging from a cost savings of $0.81 million in year 1 to a cost savings of $8.13 million in year 5, for a total 5-year budget impact of $19.03 million in cost savings. We identified a previously published rapid review that found no qualitative literature on the patient experience of ICGFI. However, qualitative studies on the experience of patients who had undergone colorectal cancer surgery identified anastomotic leak and quality of life as key patient-important outcomes. In the included studies, patients often reported not receiving enough information about surgical outcomes and experiencing anxiety regarding cancer recurrence. We did not conduct direct patient engagement since the purpose of the technology is to enhance visualization of the surgical area and because it is expected that patients' preferences and values would align with the potential for improved health outcomes from the use of ICGFI in colorectal surgery.

The evidence suggests that, compared with visual assessment alone, adding ICGFI to colorectal surgery can help reduce anastomotic leaks, reoperations, and sepsis but may not have an effect on hospital readmissions or length of stay. The effect of ICGFI on mortality is unclear. ICGFI is more effective and less costly than visual assessment alone. We estimate that publicly funding ICGFI for colorectal surgery in Ontario would result in cost savings of $19.03 million over the next 5 years. No literature was found on the patient experience of ICGFI. The qualitative literature on preferences and values for patients who had undergone colorectal cancer surgery identified anastomotic leak and quality of life as key outcomes, with study participants expressing concerns about surgical outcomes and cancer recurrence.