Anatomical study of partial anomalous pulmonary venous return with special references to the bronchial vein: supplementary report.

After the authors' previous report an additional case of partial anomalous pulmonary venous return was encountered during dissection practice for medical students. In an 87-year-old Japanese male cadaver, the anomalous vein from the right upper lobe drained into the superior vena cava at a point just below the entrance of the azygos vein. This case is similar to the first case in the authors' previous report, but the anomalous vein was recognized before dissection of the lung began. Therefore, findings were more precisely observed. The anomalous pulmonary vein was 16 mm in diameter and had three branches, which drained the regions of the apex, the anterior segment and a part of the posterior segment of the right upper lobe. The other veins from the right lung gathered into two pulmonary veins, measuring 21 mm and 18 mm in diameter, respectively, and returned to the left atrium as usual. It is noteworthy that the anomalous vein received the bronchial vein from the right upper lobe bronchus. The azygos vein also received the bronchial veins from the lower part of the trachea and from the right middle and lower lobe bronchi. The theory that the bronchial vein plays an important role in the occurrence of the anomalous pulmonary drainage is further supported by this finding.