A case of double superior vena cava and classification of Japanese cases reported.

The author' case was a 74 year-old Japanese female who died of senility. This case had a small-sized communicating branch corresponding to the left brachiocephalic vein and uniting bilateral superior venae cavae. 2 anastomotic branches were observed among the azygos, the hemi-azygos and the accessory hemiazygos vein, and also a small anastomotic branch between the accessory hemiazygos vein and the left s.v.c. The venous valves were observed in both of the internal jugular, both of the external jugular and both of the subclavian veins. We also referred to 56 Japanese cases of d.s.v.c. including this case and classified it in accordance with the method of McCOTTER (1916), and they were shown in Table 1. In Japan, there were 17 (30.4%) cases of d.s.v.c. without a communicating branch and 22 (39.3%) cases with the communicating branch. Therefore, a comparison between the figures of McCotter and the present author's showed the reverse result.