Indocyanine green perfusion assessment of the gastric conduit in minimally invasive Ivor Lewis esophagectomy

Current status of indocyanine green fluorescent angiography in assessing perfusion of gastric conduit and oesophago-gastric anastomosis

Anastomotic leak (AL) remains a significant complication after esophagectomy. Indocyanine green fluorescent angiography (ICG-FA) is a promising and safe technique for assessing gastric conduit (GC) perfusion intraoperatively. It provides detailed visualization of tissue perfusion and has demonstrated usefulness in oesophageal surgery. GC perfusion analysis by ICG-FA is crucial in constructing the conduit and selecting the anastomotic site and enables surgeons to make necessary adjustments during surgery to potentially reduce ALs. However, anastomotic integrity involves multiple factors, and ICG-FA must be combined with optimization of patient and procedural factors to decrease AL rates. This review summarizes ICG-FA's current applications in assessing esophago-gastric anastomosis perfusion, including qualitative and quantitative analysis and different imaging systems. It also explores how fluorescent imaging could decrease ALs and aid clinicians in utilizing ICG-FA to improve esophagectomy outcomes.

Intraoperative assessment of anastomotic blood supply using indocyanine green fluorescence imaging following esophagojejunostomy or esophagogastrostomy for gastric cancer

Objective

This retrospective study aimed to evaluate the feasibility and safety of intraoperative assessment of anastomotic blood supply in patients undergoing esophagojejunostomy or esophagogastrostomy for gastric cancer using Indocyanine Green Fluorescence Imaging (IGFI).

Materials and methods

From January 2019 to October 2021, we conducted a retrospective analysis of patients who had undergone laparoscopic gastrectomy for the treatment of gastric cancer. The patients were consecutively enrolled and categorized into two study groups: the Indocyanine Green Fluorescence Imaging (IGFI) group consisting of 86 patients, and the control group comprising 92 patients. In the IGFI group, intravenous administration of Indocyanine Green (ICG) was performed, and we utilized a fluorescence camera system to assess anastomotic blood supply both before and after the anastomosis.

Results

The demographic characteristics of patients in both groups were found to be comparable. In the IGFI group, the mean time to observe perfusion fluorescence was 26.3 ± 12.0 seconds post-ICG injection, and six patients needed to select a more proximal resection point due to insufficient fluorescence at their initial site of choice. Notably, the IGFI group exhibited a lower incidence of postoperative anastomotic leakage, with no significant disparities observed in terms of pathological outcomes, postoperative recovery, or other postoperative complication rates when compared to the control group (p > 0.05).

Conclusion

This study underscores the potential of IGFI as a dependable and pragmatic tool for the assessment of anastomotic blood supply following esophagojejunostomy or esophagogastrostomy for gastric cancer. The use of IGFI may potentially reduce the occurrence of postoperative anastomotic leakage.

A quantitative assessment of perfusion of the gastric conduit after oesophagectomy using near-infrared fluorescence with indocyanine green

INTRODUCTION

Anastomotic leakage is a severe complication after oesophageal resection with gastric conduit reconstruction. Poor perfusion of the gastric conduit plays an important role in the development of anastomotic leakage. Quantitative near-infrared (NIR) fluorescence angiography with indocyanine green (ICG-FA) is an objective technique that can be used for perfusion assessment. This study aims to assess perfusion patterns of the gastric conduit with quantitative ICG-FA.

METHODS

In this exploratory study, 20 patients undergoing oesophagectomy with gastric conduit reconstruction were included. A standardized NIR ICG-FA video of the gastric conduit was recorded. Postoperatively, the videos were quantified. Primary outcomes were the time-intensity curves and nine perfusion parameters from contiguous regions of interest on the gastric conduit. A secondary outcome was the inter-observer agreement of subjective interpretation of the ICG-FA videos between six surgeons. The inter-observer agreement was tested with an intraclass correlation coefficient (ICC).

RESULTS

In a total of 427 curves, three distinct perfusion patterns were recognized: pattern 1 (steep inflow, steep outflow); pattern 2 (steep inflow, minor outflow); and pattern 3 (slow inflow, no outflow). All perfusion parameters were significantly different between the perfusion patterns. The inter-observer agreement was poor - moderate (ICC:0.345,95%CI:0.164-0.584).

DISCUSSION

This was the first study to describe perfusion patterns of the complete gastric conduit after oesophagectomy. Three distinct perfusion patterns were observed. The poor inter-observer agreement of the subjective assessment underlines the need for quantification of ICG-FA of the gastric conduit. Further studies should evaluate the predictive value of perfusion patterns and parameters on anastomotic leakage.