Beyond the usual suspects: An unusual cause of pulmonary aneurysm.

Bronchial artery to pulmonary artery fistula is a rare entity, and presence of an associated aneurysm in such cases is even more uncommon. This case report describes the case of a patient with an incidental diagnosis of a pulmonary aneurysm. The etiology was challenging to determine on noncontrast CT chest. The inflow bronchial artery and outflow pulmonary artery vasculature were delineated with Cone Beam CT, which helped guide management. The aneurysm was then treated with embolization of the inflow bronchial artery. This report presents a unique case utilizing Cone Beam CT in diagnosis and treatment planning, and highlights the diagnostic challenges of this rare entity, as well as utility of Cone Beam CT in further evaluation.