# Real‐Time Identification of Lymph Vessels Using Indocyanine Green in a Patient With Chylothorax Associated With Lymphangioleiomyomatosis

## TL;DR

This paper describes using indocyanine green to identify lymph vessels in real time during surgery for a patient with lymphangioleiomyomatosis and chylothorax.

## Contribution

This is the first report of using indocyanine green lymphangiography to locate a chyle fistula in LAM during surgery.

## Key findings

- Indocyanine green enabled real-time visualization of lymphatic pathways and the chyle fistula during surgery.
- The technique allowed precise localization and treatment of the fistula, reducing chyle effusion.
- Ligation and coagulation of the affected lymphatic structures led to decreased chylous effusion.

## Abstract

Lymphangioleiomyomatosis (LAM) is often complicated by chylothorax and may require surgical intervention; however, the treatment is complicated because of difficulties in identifying the location of the fistula intraoperatively. This is the first report to identify the site of a chyle fistula associated with LAM in real time during surgery by using indocyanine green (ICG) lymphangiography.

A 56‐year‐old woman received a diagnosis of a treatment‐resistant left chylothorax associated with LAM. To identify the chyle fistula during surgery, 1 mL of ICG (2.5 mg) was injected into both inguinal lymph nodes under ultrasound guidance after anesthesia, with 1 mL per side for a total of 5 mg of ICG. We performed video‐assisted thoracic surgery and observed near‐infrared light acquisition and overlay technology using Stryker. Approximately 1 h after administration, fluorescence was observed in the anterior mediastinal lymph nodes, and a chyle fistula was observed around them. Although we attempted ligation of the lymph trunk, the surgical procedure damaged well‐developed lymph vessels. The damaged area and anterior mediastinal lymph nodes, including the surrounding lymph vessels, were incinerated using soft coagulation and covered with polyglycolic acid sheets and fibrin glue. Consequently, the amount of chylous effusion decreased.

The use of ICG allowed visualization of the lymphatic pathway and location of the chyle fistula in real time during surgery, enabling precise local treatment to reduce chyle effusion.