A Case of Preoperative Diagnosis of Pulmonary Artery Aneurysm Resected by Segmentectomy.

A pulmonary artery aneurysm (PAA) is a rare condition. It is treated in various ways, depending on its location and size. Herein, we describe the preoperative diagnosis of a PAA that was resected by segmentectomy. A 44-year-old female underwent CT, which revealed a 15-mm saccular protrusion in the right pulmonary artery and was diagnosed with PAA. The patient was initially observed without requiring further treatment, but a gradual increase in size led to therapeutic intervention. Because the PAA was located just peripheral to the right A8 bifurcation, embolization using interventional radiology was deemed too difficult. Therefore, a surgical intervention was planned. Subsequently, S8 segmentectomy, basal segmentectomy, and basilar pulmonary artery ligation were all considered. Ultimately, basal segmentectomy was selected because it allowed the resection of the pulmonary artery and did not result in invalid ventilation of the basal segment. A basal segmentectomy was performed, and the PAA was safely removed without hemorrhage. Histopathological examination revealed arterial and venous wall-like areas, and the patient was diagnosed with pulmonary artery malformation. A PAA is typically treated with coil embolization, ligation of the pulmonary artery, aneurysmectomy, and lung resection; however, no clear treatment guidelines exist. After discussion, we selected basal segmentectomy as a safe and minimally invasive procedure, and we resected the PAA without complications. The optimal treatment strategy for PAAs varies according to location and size, and a careful treatment plan should be established.