Effective application of indocyanine green for visualization of the thoracic duct during video-assisted thoracoscopic surgery for chylothorax: a case report.

Background: Chylothorax is an accumulation of typically milky-appearing lymphatic fluid within the pleural cavity. High-output chylothorax may lead to a severe risk of death if not treated promptly. Several studies have reported the effectiveness of indocyanine green (ICG) for chylothorax following lung cancer surgery, esophagectomy, and congenital and recurrent idiopathic chylothorax. Here, we report a case of a successful treatment of idiopathic chylothorax in an adult by identifying and ligating the thoracic duct (TD) using fluorescent thoracoscopy with inguinal lymph node injection of ICG. Case presentation: A 79-year-old man with nephrotic syndrome presented with a massive right pleural effusion. Based on the pleural effusion examination, the patient was diagnosed with idiopathic chylothorax. He underwent 26 days of conservative treatments, including intercostal chest tube drainage, subcutaneous injection of a somatostatin analog (octreotide), and diet control (low-fat diet, fasting). However, the conservative treatments failed. Therefore, thoracoscopic TD ligation using a combination of ICG and near-infrared (NIR) light was performed. Ultrasound-guided inguinal lymph node injection of ICG was performed before thoracoscopy. Although standard-mode thoracoscopy could not identify leakage points, when observed under NIR light, the TD could be detected using fluorescence contrast. The TD was clipped to the deepest level on the thoracic side. Furthermore, a fluorescence hotspot of ICG on the cranial side of the clipped TD, likely a leakage point, was confirmed, and the lesion was clipped. ICG fluorescence did not disappear during surgery. The thoracic tube was removed on postoperative day 7. To date, chylothorax has not recurred. Conclusions: We report the effectiveness of intraoperative NIR fluorescence with ICG in identifying the TD's running. This technique can lead us to identify and ligate the TD with assurance and accurately treat chylothorax. [ABSTRACT FROM AUTHOR]