Indocyanine green inhalation visualizes lung tumour during video-assisted thoracoscopic surgery

Accurate intraoperative identification of small lung tumours is crucial for precise resection of these lesions during video-assisted thoracoscopic surgery. This study aimed to evaluate the feasibility and safety of indocyanine green (ICG) inhalation for intraoperative visualization of lung tumours.

From January 2022 to May 2022, 43 patients with lung nodules were included into this study. All patients received intraoperative ICG inhalation for visualization of lung tumours under near-infrared imaging. The primary outcomes of this trial were the detection rate and background-tumour ratio of lung nodules, and the secondary objectives were time to search for nodules and operative time to nodules excision.

A total of 50 pulmonary nodules in 43 patients were identified and completely resected. And 44 lung nodules were detected during intraoperative fluorescent exploration with a median inhaled ICG dose of 18.8 mg. In vivo, the median background-tumour ratio was 7.10. The median detection time of nodules was 100 s and the median operative time to nodules excision was 18 min. Quantification analysis showed that the fluorescence intensity of postoperative sputum declined to ∼10% of the first fluorescent sputum within 20 h. No adverse events attributed to ICG inhalation were recorded during the follow-up period.

Intraoperative inhalation of ICG was a feasible and safe method for detection of lung tumours at low dose of ICG. This technique could be a remedial measure for identification of unpalpable lung nodules without preoperative localization.

Chinese Clinical Trial Registry, Identifier: ChiCTR2100053708.