Case Report: Thoracic duct ligation for left-sided chylothorax after pneumonectomy with contralateral VATS procedure using indocyanine green fluorescence.

Introduction: Chylothorax is a rare but potentially life-threatening condition characterized by the accumulation of lymphatic fluid in the pleural cavity. It is typically managed with conservative treatments such as fasting and/or thoracic duct embolization via lymphography. However, when these approaches fail, surgical intervention, most commonly thoracic duct ligation (TDL), is often necessary. While the advent of video-assisted thoracoscopic surgery (VATS) has enabled minimal invasive approaches for thoracic duct ligation, intraoperative identification of the thoracic duct remains technically challenging. Case report: We present the case of a 62-year-old man diagnosed with SMARCB1-deficient mediastinal sarcoma who underwent left pneumonectomy and subsequently developed a left-sided chylothorax on postoperative day 16. Initial management with conservative strategy first, including two lymphography procedures with attempted embolization, was unsuccessful. Consequently, we proceeded with thoracic duct ligation via right-sided VATS, employing indocyanine green (ICG) fluorescence to aid in the identification of the thoracic duct. Given the prior left pneumonectomy, a single-lumen endotracheal tube with a bronchial blocker was used to selectively exclude the right lower lobe during the procedure. Conclusion: This case highlights the use of ICG fluorescence in facilitating the identification and ligation of the thoracic duct in a patient with left-sided chylothorax following left pneumonectomy.