Near-Infrared Indocyanine Green-Enhanced Fluorescence and Evaluation of the Bowel Microperfusion During Robotic Colorectal Surgery: a Retrospective Original Paper.

BACKGROUND: Leakage of the anastomosis after colorectal surgery is a severe complication, and one of the most important causes is poor vascular supply. However, a microvascular deficit is often not detectable during surgery under white light. Near-infrared indocyanine green (ICG)-enhanced fluorescence may be useful for assessing microvascular deficits and conceivably preventing anastomotic leakage. OBJECTIVES: This paper presents a preliminary retrospective case series on robotic colorectal surgery. The aim is to evaluate the feasibility, safety and role of near-infrared ICG-enhanced ?uorescence for the intraoperative assessment of peri-anastomotic tissue vascular perfusion. MATERIALS AND METHODS: From among more than 164 robotic colorectal cases performed, we retrospectively analyzed 28 that were all performed by the same surgeon (PCG) using near-infrared ICG-enhanced fluorescence technology: 16 left colectomies (57.1%), 8 rectal resections (28.6%), 3 right colectomies (10.8%) and 1 pancolectomy (3.6%). RESULTS: The rates of conversion, intraoperative complications, dye allergic reaction and mortality were all 0%. In two cases (7.1%)-1 left and 1 right colectomy-the level of the anastomosis was changed intraoperatively after ICG showed ischemic tissues. Despite the application of ICG, one anastomotic leak (after left colectomy for a chronic recurrent sigmoid diverticulitis with pericolic abscess) was observed. CONCLUSIONS: ICG technology may help to determine when to intraoperatively change the anastomotic level to a safer location. In our case series, ICG results led to a change in the level of the anastomosis in 7.1% of the cases. Despite the use of ICG, we observed one leak. This may have been related to vascularization-independent causes (e.g., infection in this case) or may reflect a need for better standardization of this ICG technology. In particular, we need a way to objectively assess the ICG signal and the related risk of leakage. More randomized, prospective, well-powered trials are needed to unveil the full potential of this innovative surgical technology.

Near-Infrared Indocyanine Green-Enhanced Fluorescence and Minimally Invasive Colorectal Surgery: Review of the Literature.

BACKGROUND: Leakage of the anastomosis after colonic/rectal surgery is a serious complication. One of the most important causes of anastomotic leakage is impaired vascularization. A microvascular tissue deficit is very often not intraoperatively de visu detectable under white light. Near-infrared indocyanine green (ICG)-enhanced fluorescence is a cutting-edge technology that may be useful for detecting microvascular impairment and potentially preventing anastomotic leakage. AIM: The aim of this narrative review was to evaluate the feasibility and the usefulness of intraoperative assessment of vascular anastomotic perfusion in colorectal surgery using an indocyanine green (ICG) fluorescent tracer. MATERIAL AND METHODS: A PubMed/MedLine, Embase, and Scopus narrative literature review was performed, in which "colorectal surgery" and "indocyanine green" were used as key words. The inclusion criteria were 1) manuscripts written in English; 2) full text is available; 3) topic related to the use of ICG fluorescence for the assessment of tissue perfusion during laparoscopic or robotic colorectal surgery; and 4) sample: adult patients, benign or malignant disease. Exclusion criteria included 1) case reports; 2) topic not related to the use of ICG fluorescence for the evaluation of tissue perfusion during laparoscopic or robotic colorectal surgery; 3) manuscripts that focused solely on other applications of ICG technology; and 4) any study type not showing original data. Results and Critical Discussion: The intraoperative visual assessment of tissue viability under white light may lead to an underestimation of microvascular blood flow impairment. ICG can be safely used in cases of minimally invasive colonic surgery and also low anterior resections. This technology may be useful when deciding whether to intraoperatively change a previously planned resection/anastomotic level, which could decrease theoretically the occurrence of anastomotic leakage. CONCLUSIONS: Near-infrared ICG technology is a very useful approach. Multiple preliminary studies suggest that this technique may be used to predict anastomotic leakage. However, evaluation of the ICG signal is still too subjective. Some reliable scoring/grading parameters related to the ICG signal need to be defined. Additionally, more prospective, randomized, and adequately powered studies are required to completely reveal the true potential of this surgical technological innovation.

Indocyanine Green (Icg)-Enhanced Fluorescence for Intraoperative Assessment of Bowel Microperfusion During Laparoscopic and Robotic Colorectal Surgery: The Quest for Evidence-Based Results.

Anastomotic leakage is a severe complication after colonic/rectal surgery. One of the most important causes of anastomotic leakage is poor vascular supply. However, microvascular impairment at the anastomotic site is very often not detected intraoperatively by observation under white light. Indocyanine green (ICG)-enhanced fluorescence is a technology that may be useful for detecting microvascular alterations and potentially preventing anastomotic leakage. The aim of this Editorial-Minireview is to briefly and critically assess the literature evidence regarding the feasibility of using an ICG ?uorescent tracer for detecting microvascular changes in the perianastomotic tissue and its potential role in preventing anastomotic leakage. We focused on minimally invasive (robotic and laparoscopic) colorectal surgery. Intraoperative ICG angiography and the quantification of ICG kinetics can be used to intraoperatively reveal the tissue-perfusion status during colorectal surgery. This may be useful for intraoperatively changing a previously planned resection/anastomotic level, and conceivably decreasing the degree of anastomotic leakage. At this stage, even though ICG technology appears to be very promising and some preliminary clinical studies have suggested that certain ICG pharmacokinetic parameters may be used to predict leakage, more reliable scoring and grading tools are needed. Furthermore, in minimally invasive colorectal surgery, more randomized prospective well-powered trials are needed to properly standardize this surgical technology.