[Idiopathic Bronchial-pulmonary Artery Fistula with Intraoperative Definitive Diagnosis by Intravenous Administration of Indocyanine Green].

The patient is a 73-year-old woman who was referred to our department for diagnostic surgery. A part-solid ground-glass nodule, suspected to be lung cancer, was identified in the right S6 on a preoperative chest contrast computed tomography (CT). Additionally, a continuous bronchial artery was observed at the root of A6. Based on the CT findings, we diagnosed a bronchial-pulmonary artery fistula (BPAF) and an associated pulmonary artery aneurysm. The patient exhibited no subjective symptoms, such as blood-streaked sputum or hemoptysis. She subsequently underwent a right S6 segmentectomy. Intraoperative examination of the pulmonary artery revealed a continuous bronchial artery dorsal to A6, as anticipated. Intravenous indocyanine green (ICG) administration after root ligation of A6 showed that ICG flowed into A6 and peripherally to S6 beyond the ligated point via the bronchial artery, confirming the diagnosis of BPAF.