[The role and significance of digital reconstruction technique in liver segments based on portal vein structure].

Objective: To study the segment of liver according to the large amount of three-dimensional(3D) reconstructive images of normal human livers and the vascular system, and to recognize the basic functional liver unit based on the anatomic features of the intrahepatic portal veins. Methods: The enhanced CT primitive DICOM files of 1 260 normal human livers from different age groups who treated from October 2013 to February 2017 provided by 16 hospitals were analyzed using the computer-aided surgery system.The 3D liver and liver vascular system were reconstructed, and the digital liver 3D model was established.The vascular morphology, anatomical features, and anatomical distributions of intrahepatic portal veins were statistically analyzed. Results: The digital liver model obtained from the 3D reconstruction of CAS displayed clear intrahepatic portal vein vessels of level four.Perform a digital liver segments study based on the analysis of level four vascular distribution areas.As the less anatomical variation of left hepatic portal vein, the liver was classified into four types of liver segmentation mainly based on right hepatic portal vein.Type A was similar to Couinaud or Cho's segmentation, containing 8 segments(537 cases, 42.62%). Type B contained 9 segments as there are three ramifications of right-anterior portal vein(464 cases, 36.82%). The main difference for Type C was the variation of right-posterior portal vein which was sector shape(102 cases, 8.10%). Type D contained the cases with special portal vein variations, which needs three-dimensional simulation to design individualized liver resection plan(157 cases, 12.46%). These results showed that there was no significant difference in liver segmental typing between genders(χ(2)=2.179, P=0.536) and did not reveal any significant difference in liver segmental typing among the different age groups(χ(2)=0.357, P=0.949). Conclusions: The 3D digital liver model can demonstrate the true 3D anatomical structures, and its spatial vascular variations.The observation of anatomic features, distribution areas of intrahepatic portal veins and individualized liver segmentation achieved via digital medical 3D visualization technology is of great value for understand the complexity of liver anatomy and to guide the precise hepatectomy.目的： 探讨人类正常肝脏及血管系统的三维重建影像，了解以基本功能性肝单位的门静脉走行为基准的肝脏分段。 方法： 收集2013年10月至2017年2月中国16家医院提供的1 260例各年龄段人类正常肝脏的增强CT原始DICOM文件，运用计算机辅助手术系统进行分析，三维重建出肝脏、肝内血管系统，建立数字化肝脏三维模型，对门静脉的血管形态、走行、支配区域进行统计分析。 结果： 计算机辅助手术系统三维重建获得的数字化肝脏模型可清晰显示门静脉四级血管，分析基于门静脉四级血管供应区域的数据并进行数字肝脏分段。由于左半肝门静脉变异较少，基于右前支变化分为A、B型两型，其中A型右前支分为两主支与Couinaud及Cho分段类似，分为8段(537例，42.62%)，B型右前支分为三主支，分为9段(464例，36.82%)。C型右后支呈扇形分布(102例，8.10%)。将多种特殊变异类型归为D型(157例，12.46%)。肝段分型在不同性别构成中差异无统计学意义(χ(2)＝2.179，P＝0.536)，在不同年龄组中分布差异无统计学意义(χ(2)＝0.357，P＝0.949)。 结论： 三维数字化肝脏模型能显示肝内真实的立体解剖关系和空间管道变异，通过数字医学三维可视化技术对门静脉解剖结构、支配区域进行观察并进行个体化肝脏分段，在充分认识肝脏解剖复杂性的基础上强调个性化肝脏解剖对于精准肝切除具有重要意义。.