Editor

We are grateful to Lin and his colleagues for their letter1 in response to our article2. We stated that the hepatic venous system of the right posterior section was classified into 8 types, and an inverse relationship was observed between the diameter of the right hepatic vein (RHV) and inferior right hepatic vein.

The data presented by Lin et al. are interesting and we also think that it is important to evaluate the correlation between the dominant area of the RHV and portal vein (especially among segment 7 and segment 8) in the anterior and posterior segments.

However, the boundary of the anterior and posterior segments is defined based on the monumental studies of the past. Healy and Schrov, Healy, and Goldsmith mentioned that the RHV exists between the anterior and posterior segments, and the RHV dominates the area of both the anterior and posterior segments3-5. Therefore, although Lin et al. have mentioned that the RHV drained only segment 8 as in type 4, it is impossible that the RHV drained only segment 8 according to the definition of the anterior and posterior segments.

In our study, we found a case in which the anterior segmental portal vein developed and dominated not only the anterior segment but also segment 7 (Fig. 1). Therefore, in the cases presented by Lin et al. it should be considered that the portal vein in the anterior segment developed and dominated segment 7 and would be classified as type 2c based on our criteria. Consequently, we can argue that our classification is based on the results of past liver anatomy studies.

The anterior segmental portal vein develops and dominates not only the anterior segment but also segment 7 and this case is classified as type 2c based on our criteria

In addition, we believe that future studies are necessary to accurately reveal the venous and portal anatomy of the anterior and posterior segments.