Objective: To investigate the anatomy of right portal vein based on three-dimensional (3D) visualization technology and provide a morphological basis for computer-assisted individualized liver segmentation and anatomical hepatectomy.
Methods: Liver CT data of 83 cases were segmented and reconstructed using the medical image three-dimensional visualization system (MI-3DVS), and 3D classifications of the right portal vein were established according to its branch number, direction and distribution. Individualized liver segmentation was performed based on the 3D typing results.
Results: The reconstructed portal vein models were capable of visualizing the fourth-order portal branches. Generally, the third-order right portal branches were classified into P5, P6, P7 and P8 branches. According to the 3D distribution of the branches, P5 branches were classified into types A, B, C, D, and E [in 16 (19.3%), 5 (6%), 30 (36.1%), 7(8.5%), and 25 (30.1%) cases, respectively], P8 branches into types A, B, C, and D [in 29 (34.9%), 29 (34.9%), 10 (12.1%), and 15 (18.1%) cases, respectively], P6 branches into types A, B, C, and D [in 35 (42.2%), 12 (14.5%), 33 (39.7%), and 3 (3.6%) cases, respectively], and P7 branches into types A, B, C, D, E, and F [in 27 (32.5%), 11(33.3%), 27 (32.5%), 4(4.8%), 12 (14.5%), and 2 (2.4%) cases, respectively]. Individualized liver segmentation was achieved based on liver segments supplied by the third-order portal branches.
Conclusion: 3D classifications of the complex and highly variant anatomy of third-order right portal vein and individualized liver segmentation based on this classification before the operation facilitates successful performance of anatomical hepatectomy.