# Indocyanine green combined with autologous blood and methylene blue for pulmonary nodules localization in 272 cases: a novel localization method

## TL;DR

A new method using indocyanine green, autologous blood, and methylene blue successfully and safely locates small lung nodules during surgery.

## Contribution

A novel combination of dyes and blood for precise, safe localization of pulmonary nodules during thoracoscopic surgery.

## Key findings

- The localization success rate was 98.53%, with 100% success at 0.2–0.5 mL injection volumes.
- All resected tissues contained the nodules with negative margins.
- Excessive dye caused pleural staining in 4 cases.

## Abstract

To explore the feasibility and safety of using indocyanine green combined with autologous blood and methylene blue for the localization of small pulmonary nodules in thoracoscopic wedge resection. Patients who met the inclusion criteria underwent CT-guided percutaneous lung puncture injection of localization agents to locate pulmonary nodules at our center from November 2023 to September 2024. Under thoracoscopy, pulmonary nodules were visualized, and wedge resection was performed. The feasibility was preliminarily verified by evaluating whether the localization agent concentrated around the nodules and help surgeons successfully completed wedge resection under marker guidance. The safety was verified by the incidence of adverse reactions during puncture and surgery. A total of 272 patients were included, comprising 110 males and 162 females, with an average age of 50.60 (14.17) years. In all cases except the first four, the localization agent concentrated around the nodules, achieving precise localization of pulmonary nodules. Nodules were found in all resected tissues, with negative margins. In 4 patients, excessive localization agent dosage caused marker diffusion and pleural staining. The overall localization success rate was 98.53%, and when the injection volume of the localization agent was 0.2–0.5 mL, the localization success rate was 100.0%. All cases successfully completed thoracoscopic wedge resection, and nodule lesions were found with negative margins. Indocyanine green combined with autologous blood and methylene blue for the localization of small pulmonary nodules is safe and feasible in lung wedge resection.