The role of ICG NIRL fluorescence imaging in the surgical treatment of digestive system tumors (Review)

Abstract

Indocyanine green (ICG) is a relatively non‑toxic fluorescent dye with a history of safe use, which has fueled the development of new applications for ICG. Research on the use of ICG near‑infrared light (NIRL) fluorescence imaging during oncologic surgery has increased, revealing its role in tumor identification and localization, lymph node navigational resection and blood perfusion assessment. The purpose of the present review was to provide a comprehensive overview of advances in the clinical application of ICG NIRL fluorescence imaging during gastrointestinal tumor surgery. The present review discusses the techniques, outcomes, limitations and key considerations necessary for clinical practice, aiming to provide a valuable resource for professionals in the field.

Keywords: indocyanine green; minimally invasive surgery; near‑infrared optical imaging; targeted surgery; tumor localization.

Figure 1.

Schematic of the fluorescence properties and clinical applications of ICG. Spectral absorption peak of ICG in plasma or blood is between 800 and 810 nm, with an emission peak at 835 nm. These wavelengths enable tissue penetration up to a depth of ~1 cm, making it suitable for visualizing structures within 8 mm of tissue depth. Consequently, ICG is an effective visual dye for NIRL fluorescence imaging-guided tumor surgery, facilitating the identification and precise localization of structures that require removal or preservation, such as tumor tissues and lymph nodes. ICG, indocyanine green; NIRL near infrared light.

Figure 2.

ICG NIRL fluorescence imaging in various tumor surgeries. Illustration delineates the application of ICG NIRL fluorescence imaging in surgeries for liver cancer, gastric cancer, esophageal cancer and colorectal cancer, encompassing details such as the injection dosage, ICG concentration, timing of injection and the site of injection. ICG, indocyanine green; iv, intravenous; NIRL, near infrared light.