A Case of Superior Vena Cava Obstruction Associated with Dilatation of Bronchial Submucosal Vessels which Were considered as Bronchial Veins

Abstract

A case of superior vena cava obstruction associated with dilatation of bronchial submucosal vessels is reported. This case is a 18-year-old male who was diagnosed as having mediastinal tumor (malignant germ cell tumor) for which irradiation and chemotherapy were administered at 16 years of age. The patient is now in complete remission. Fiberoptic bronchoscopy showed dilated submucosal vessels which extended from trachea to both upper lobe bronchi and to intermediate bronchus along the longitudinal axis of the bronchi. Angiogram and chest CT disclosed that the superior vena cava was completely obstructed and that the blood from the upper half of the body returned to the inferior vena cava via well developed collateral pathwaies (azygos, hemiazygos vein). It is well known that bronchial blood from the hilar region drains through the bronchial veins into the azygos or hemiazygos vein, whereas blood from the remaining parts of the bronchi reaches the pulmonary veins via the bronchial venous plexus. Therefore, the dilated submucosal vessels in this case were supposed to be bronchial veins which developed because of the disturbance of drainage into the azygos or hemiazygos vein, or because of the reversed pathway leading from the azygos or hemiazygos vein to the pulmonary vein.