Objective: To explore a novel method for preoperative precision assessment of centrally located hepatocellular carcinoma(HCC) with blood vessel as axis based on three-dimensional(3D) visualization and virtual reality(VR) technology and its application values. Methods: High-quality thin-layer enhanced CT data were collected from 20 patients with centrally located HCC who treated at First Department of Hepatobiliary Surgery, Zhujiang Hospital, Southern Medical University from March 2017 to August 2018 diagnosed by preoperative examination. There were 18 males and 2 females, aged 28 to 69 years, all of Child-Pugh grade A. First of all, 3D reconstruction was performed by a 3D visualization software; then, the reconstructed 3D image was imported into VR development engine for VR research; afterwards, the analysis and evaluation system with blood vessel as axis was established based on 3D visualization classification of centrally located HCC; therefore, the relationship of the tumor to its major peripheral blood vessels was accurately judged and the surgical planning was formulated. Two images were brought into the operating room for navigation in surgery. The assessments results of preoperative data (CT and (or) MRI) and three-dimensional visualization of blood vessels in VR environment were compared; the values of the preoperative and postoperative hemoglobin, serum albumin and bilirubin were recorded and compared. Chi-square test, t-test and non-parametric test were used for the analysis of counting data, continuous measurement data and non-normal distribution measurement data, respectively. Results: 3D visualization modeling was completed in all of the 20 patients with centrally located HCC. According to the results of 3D visualization classification of centrally located HCC, there were 3 cases of type Ⅰ,1 case of type Ⅱ,4 cases of type Ⅲ,7 cases of type Ⅳ and 5 cases of type Ⅴ; according to the assessment and classification based on blood vessel as the axis, there were 6 cases of type Ⅰa,2 cases of type Ⅰb,2 cases of type Ⅱa,9 cases of type Ⅱb and 1 case of type Ⅱc. All patients underwent successful resection of tumor under the guidance of 3D visualization and VR technology. There were 15 cases whose assessment results based on preoperative CT/MRI were consistent with intraoperative findings, with a coincidence rate of 75.0%(15/20); while in VR environment, the assessment results of 3D visualization with blood vessel as axis were all consistent with the intraoperative findings, with coincidence rate of 100%(20/20). There was a statistically significant difference between the groups (χ(2)=5.714, P=0.017). There was no red blood cell transfusion in all patients during the operation. The preoperative hemoglobin was (128.8±14.9)g/L, and it was (119.8±12.5)g/L on postoperative day 1. There was no significant difference between these two sets of data (t=2.07, P=0.054). No death during the perioperative period and no complications such as hepatic failure, hemorrhage and biliary fistula after operation occurred. Conclusion: Preoperative evaluation based on 3D visualization and VR technology with blood vessel as the axis has significant clinical value for preoperative planning and surgical navigation of centrally located HCC.
目的： 研究一种基于三维可视化及虚拟现实（VR）的以血管为轴心的术前精确评估中央型肝癌的新方法及其应用价值。 方法： 回顾性收集2017年3月至2018年7月南方医科大学珠江医院肝胆一科收治的经术前检查诊断为中央型肝癌的20例患者的高质量CT图像数据。男性18例，女性2例，年龄28~69岁。所有患者肝功能Child-Pugh分级均为A级。首先采用三维可视化软件对影像学资料进行三维重建，然后导入VR开发引擎进行VR的研究，在三维可视化中央型肝癌分型基础上建立以血管为轴心的分析和评估体系，精确判断肿瘤与周围主要血管的关系，制定手术规划，并将二者图像带入手术室用于指导导航手术。比较20例患者术前资料评估结果及VR环境中以血管为轴心的三维可视化评估结果，记录术前术后血红蛋白、血清白蛋白、胆红素数值并进行对比。计数资料分析采用χ(2)检验，符合正态分布的计量资料比较采用t检验，非正态分布的计量资料比较采用非参数检验。 结果： 20例中央型肝癌患者均成功进行了三维重建，按照中央型肝癌三维可视化分型结果如下：Ⅰ型3例，Ⅱ型1例，Ⅲ型4例，Ⅳ型7例，Ⅴ型5例。以血管为轴心评估分型结果如下：Ⅰa型6例、Ⅰb型2例、Ⅱa型2例、Ⅱb型9例、Ⅱc型1例。所有患者均在三维可视化及VR指导下成功切除肿瘤，术前CT和（或）MRI评估结果与术中所见相符15例，符合率为75.0%（15/20）；在VR环境中以血管为轴心的三维可视化评估与术中探查所见均一致，符合率为100%（20/20），两者差异有统计学意义（χ(2)=5.714，P=0.017）。本组所有患者手术过程中均未输红细胞，术前血红蛋白为（128.8±14.9）g/L，术后第1天血红蛋白为（119.8±12.5）g/L，术前术后血红蛋白的差异无统计学意义（t=2.07，P=0.054）。患者围手术期无死亡，术后未发生肝功能衰竭、出血、胆瘘等并发症。 结论： 基于三维可视化及VR的以血管为轴心的术前评估对中央型肝癌术前规划及手术导航有重要的临床应用价值。.
Keywords: Axis of blood vessels; Centrally located hepatocellular carcinoma; Imaging, three dimensional; Liver neoplasms; Preoperative assessment; Virtual reality.