Abstract
The right-sided ligamentum teres of the liver is a rare anatomical variation due to the residual fetal umbilical vein of the right side. However, the ideas for vascular anatomy and hepatic areas are still controversial. We herein described a case of hepatocellular carcinoma with the right-sided ligamentum teres. A 64-year-old patient was referred to us because of a liver tumor 7 cm in diameter in the segment 8. The right-sided ligamentum teres was also pointed out on admission. We performed the resection of the dorsal part of the right para-median sector. In case of right-sided ligamentum teres, the right liver markedly becomes hypertrophied compared to the normal anatomy. Since the right para-median sector has become large, S4 tends to be atrophied. This may cause misinterpretation on the each hepatic vein, as well as the hepatic areas. Developmental vascular anatomy and the areas of the right-side ligamentum teres may help our understanding on the standard hepatic anatomy.