Intraoperative Indocyanine Green Fluorescence Angiography—An Objective Evaluation of Anastomotic Perfusion in Colorectal Surgery

Abstract

The essentials for any bowel anastomosis are: adequate perfusion, tension free, accurate tissue apposition, and minimal local spillage. Traditionally, perfusion is measured by assessing palpable pulses in the mesentery, active bleeding at cut edges, and lack of tissue discoloration. However, subjective methods lack predictive accuracy for an anastomotic leak. We used intraoperative indocyanine green (ICG) fluorescence angiography to objectively assess colon perfusion before a bowel anastomosis. Seventy-seven laparoscopic colorectal operations, between June 2013 and June 2014, were retrospectively reviewed. The perfusion to the colon and ileum was clinically assessed, and then measured using the SPY Elite Imaging System. The absolute value provided an objective number on a 0–256 gray-scale to represent differences in ICG fluorescence intensity. The lowest absolute value was used in data analysis for each anastomosis (including small bowel) to represent the theoretical least perfused/weakest anastomotic area. The lowest absolute value recorded was 20 in a patient who underwent a laparoscopic right hemicolectomy for an adenoma, with no postoperative complications. Four low anterior resection patients had additional segments of descending colon resected. There was one mortality in a patient who underwent a laparoscopic right hemicolectomy. This study illustrates an initial experience with the SPY system in colorectal surgery. The SPYprovides an objective, numerical value of bowel perfusion. However, evidence is scant as to the significance of these numbers. Large-scale randomized controlled trials are required to determine specific cutoff values correlated with surgical outcomes, specifically anastomotic leak rates.

A practical guide for the use of indocyanine green and methylene blue in fluorescence‐guided abdominal surgery

“…One study compared the anastomotic leakage rate in perfusion detection both with and without the use of ICG fluorescence imaging, which resulted in reducing the rate from 20% to 0% . Twenty‐one clinical trials reported the use of ICG as a NIR fluorescence agent with different imaging systems in intraoperative evaluation of colorectal anastomoses . ICG was often injected after anastomotic site selection to evaluate the effect of ICG in selecting the correct anastomotic site.…”

Comparison of the ViOptix Intra.Ox Near Infrared Tissue Spectrometer and Indocyanine Green Angiography in a Porcine Bowel Model

“…Intraoperative tissue perfusion assessment presents a novel approach to predicting and preventing the occurrence of anastomotic leak following left-sided colon resection with primary anastomosis. 1,3,12 Although the novel near-infrared spectroscopy (NIRS) systems have yet to be formally evaluated, the PILLAR II clinical trial demonstrated the feasibility of using ICG to this end. Angiography changed surgical plans in 8% of the cases, resulting in no clinical anastomotic leaks during the follow-up period.…”

“…Kalamazoo, MI) and PINPOINT Endoscopic Fluorescence Imagining System 3 (Stryker Co, Kalamazoo, MI) use a near infrared sensor to detect intravenously injected indocyanine green (ICG) dye within target tissue. However, the use of these dye-based systems has yet to be validated on a large scale, 10,12,13 and may come with the added cost of adverse patient reactions, 10,14 increased health care expenditure, 10 and overexcision of healthy tissue. 10 Near infrared spectroscopy offers a promising alternative to dye-based angiography techniques.…”

Perfusion Assessment in Critical Limb Ischemia: Principles for Understanding and the Development of Evidence and Evaluation of Devices: A Scientific Statement From the American Heart Association

“…Similar to LSI, ICG fluorescence angiography began as a technique for imaging retinal vessels before use in other applications, including detection of arteriovenous malformation and anastomotic perfusion monitoring after colorectal surgery. 80,81 Fluorescent ICG dye is injected intravenously. The dye is then activated with CLINICAL STATEMENTS AND GUIDELINES near-infrared laser light, producing fluorescence, which can be detected and measured.…”