インドシアニン・グリーン投与で術中確定診断を得た特発性気管支動脈肺動脈瘻

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

気管支動脈肺動脈瘻（bronchial-pulmonary artery fistula：BPAF）は気管支拡張症や肺結核，非結核性抗酸菌症などの慢性肺疾患を背景に発症するとされ1），特発性BPAFはきわめてまれである2）．診断は気管支動脈造影が一般的とされるが，われわれは肺癌の術前精査の胸部造影CTでBPAFを疑い，術中にインドシアニン・グリーン（ICG）蛍光法を用いることで確定診断を得た1例を経験したので，若干の文献的考察を加えて報告する．

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.