Indocyanine green fluorescence in gastrointestinal surgery: Appraisal of current evidence

Abstract

Applying indocyanine green (ICG) fluorescence in surgery has created a new dimension of navigation surgery to advance in various disciplines. The research in this field is nascent and fragmented, necessitating academic efforts to gain a comprehensive understanding. The present review aims to integrate diverse perspectives and recent advances in its application in gastrointestinal surgery. The relevant articles were selected by using the appropriate keyword search in PubMed. The angiography and cholangiography property of ICG fluorescence is helpful in various hepatobiliary disorders. In gastroesophageal and colorectal surgery, the lymphangiography and angiography property of ICG is applied to evaluate bowel vascularity and guide lymphadenectomy. The lack of objective parameters to assess ICG fluorescence has been the primary limitation when ICG is used to evaluate bowel perfusion. The optimum dose and timing of ICG administration need to be standardized in some new application areas in gastrointestinal surgery. Binding tumor-specific ligands with fluorophores can potentially widen the fluorescence application to detect primary and metastatic gastrointestinal tumors. The narrative review outlines prior contributions, limitations, and research opportunities for future studies across gastrointestinal sub-specialty. The findings of the present review would be helpful for scholars and practitioners to explore and progress in this exciting domain of gastrointestinal surgery.

Keywords: Angiography; Cholangiography; Fluorescence; Indocyanine green; Lymphangiography; Navigation surgery.

Figure 1

Annual publication trend of articles related to indocyanine green fluorescence.

Figure 2

Country-wise publication trend of articles related to indocyanine green fluorescence.

Figure 3

Negative indocyanine green staining technique used in a patient with hilar cholangiocarcinoma planned for right hepatectomy with caudate lobectomy. A: Portal and hepatic artery branches of the right hemiliver to be resected are ligated; B: Line of transection for right hepatectomy identified with the help of indocyanine green fluorescence.

Figure 4

Identification of bile duct during robotic duodenum preserving pancreas head resection. A: Pancreatic duct (arrow) divided at its junction with the bile duct; B: Indocyanine green fluorescence demonstrates bile duct.

Figure 5

Visualization of the thoracic duct. A and B: Visualization of the thoracic duct during robotic esophagectomy in normal mode (A) is enhanced by indocyanine green fluorescence (B); C: The branching pattern of the thoracic duct is well visualized in fluorescence mode.

Figure 6

Visualization of perigastric lymph node during robotic D2 gastrectomy in normal mode and fluorescence mode. A: In normal mode; B: In fluorescence mode.

Figure 7

Objective evaluation of colonic perfusion using indocyanine green fluorescence during low anterior resection. A and B: Increasing fluorescence levels show the transition from blue (A) to red (B) and guide the selection of the line of bowel division; C: Fluorescence is displayed on a Grayscale; D: Fluorescence displayed in overlay mode.