Adult presentation of unilateral pulmonary venous atresia: CT findings in a rare congenital anomaly.

Pulmonary venous atresia (PVA) is a rare congenital anomaly of the pulmonary venous system, most commonly diagnosed in early childhood, with adult presentations being exceedingly uncommon. We report the case of a 43-year-old male who presented with progressive dyspnea in the context of a newly diagnosed laryngeal squamous cell carcinoma. Contrast-enhanced chest CT revealed complete right pulmonary venous atresia, associated right pulmonary artery hypoplasia, a right upper lobe pulmonary arteriovenous fistula, multiple mediastinal venous collaterals, and ipsilateral parenchymal changes. Pulmonary hypertension was subsequently confirmed by right heart catheterization. This case underscores the central role of CT in identifying unilateral PVA in adults, reviews the characteristic imaging features of this rare condition, and highlights the importance of including PVA in the differential diagnosis of unilateral pulmonary abnormalities.