Fluorescence navigation with indocyanine green for identification of intersegmental planes using a photodynamic eye camera

J Thorac Dis. 2020 Sep;12(9):4817-4824. doi: 10.21037/jtd-20-1448.

Abstract

Background: Pulmonary segmentectomy is an important surgical option for complete resection in patients with poor lung function. However, correctly recognizing the intersegmental plane for accurate segmentectomy is sometimes difficult. We therefore developed a novel method that allows the detection of intersegmental planes using an indocyanine green (ICG) fluorescence imaging device, photodynamic eye (PDE) camera, PDE-neo.

Methods: As a prospective study, we performed bronchial ICG-guided segmentectomy using PDE-neo. The patients were placed in a lateral position under general anesthesia, and we performed a combined muscle-sparing minithoracotomy with video assistance. The pulmonary artery, pulmonary vein, and segmental bronchi were separated, and ICG mixed with autologous blood was introduced by spraying through the resected segment bronchi to enable visualization of the intersegmental surface with PDE-neo. This study protocol was approved by the Research Ethics Board of Hamamatsu University School of Medicine, Japan. Written informed consent was obtained from all patients.

Results: Overall, 10 lung malignancy patients, including 8 males and 2 females, participated in this study from March 2011 to October 2013. The median age was 69 years (range, 29-76 years). Pathologic diagnoses were 7 adenocarcinomas, 1 adenosquamous carcinoma, 1 carcinoid tumor, and 1 lung metastasis from the parotid gland cancer. The intersegmental planes of 8 cases could be identified by this method using a PDE-neo, whereas those of 2 cases did not show clear demarcations. The reason was that because of severe emphysema, air flowed from the resected segment to the surrounding segments, obliterating the demarcation between the two segmental planes. There were no recurrent cases and only two deaths due to other diseases were observed; and the 5-year cause-specific survival rate was 100%.

Conclusions: Intersegmental planes could be more easily identified using ICG fluorescence imaging during segmentectomy. This method is feasible and effective and has a good long-term prognosis.

Keywords: Emphysema; fluorescence imaging; indocyanine green (ICG); lung neoplasms; segmentectomy.