Xie Chiyu, Sun Shengda, Huang Hao, Li Xiaofan, Qu Wei, Song Hongqing
University of Science and Technology Beijing, Beijing, China.
Liver Transplantation Section, Department of General Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China.
Med Phys. 2024 Sep;51(9):6501-6512. doi: 10.1002/mp.17184. Epub 2024 Jun 6.
Cirrhosis patients often exhibit clinical symptoms such as right liver atrophy, portal hypertension, spleen enlargement and increased blood supply, which exhibit considerable variation between the left and right liver sections. These differences are hypothesized to stem from disparities in blood flow within the left and right portal vein (PV) branches. However, rigorous quantitative evidence remains scarce.
We mainly aim at quantitatively revealing the relationship between the blood flow rates of two PV branches and liver volumes, and providing quantitative evidence and theoretical support for the diagnosis and treatment of cirrhosis from the perspective of hemodynamics.
Five cirrhotic patients and two healthy volunteers from Beijing Friendship Hospital are investigated. Their PV blood flow models are established based on computed tomography (CT) images and finite volume simulations. The volume of the left and right liver lobes are measured in 3-matic. The distributions of blood source in the PV branches are tracked by streamline analysis. The blood flow rates are quantitatively counted by integrating the blood source velocities. Linear analysis is performed to build the relationship between liver volumes and PV blood flow distributions.
Streamline analysis reveals significant differences in blood distribution between the left and right PV branches. The majority of blood from the superior mesenteric vein (SMV) flowed into the right portal vein (RPV), while most blood from the splenic vein (SV) entered the left portal vein (LPV). The main PV pressure drop linearly increases with the SV blood velocity for all PV structures of patients and healthy volunteers. The flow rate ratio Q/Q demonstrates an increase in tandem with the volume ratio V/V, exhibiting a linear correlation with the Pearson correlation coefficient being 0.93.
The differences in the blood distributions are consistent with the clinicians' knowledge and validate our simulations. We demonstrated a linear increase in PV pressure with elevated SV blood velocity. Additionally, the volumes of the left and right hepatic lobes exhibited a positive correlation with blood flow rates in the corresponding PV branches.
肝硬化患者常表现出如右肝萎缩、门静脉高压、脾肿大和血供增加等临床症状，这些症状在左右肝段之间存在显著差异。据推测，这些差异源于左右门静脉（PV）分支内血流的差异。然而，严格的定量证据仍然匮乏。
我们主要旨在定量揭示两个PV分支的血流速率与肝脏体积之间的关系，并从血流动力学角度为肝硬化的诊断和治疗提供定量证据和理论支持。
对北京友谊医院的5名肝硬化患者和2名健康志愿者进行了研究。基于计算机断层扫描（CT）图像和有限体积模拟建立了他们的PV血流模型。在3-matic中测量左右肝叶的体积。通过流线分析追踪PV分支中血源的分布。通过对血源速度进行积分来定量计算血流速率。进行线性分析以建立肝脏体积与PV血流分布之间的关系。
流线分析揭示了左右PV分支之间血液分布的显著差异。肠系膜上静脉（SMV）的大部分血液流入右门静脉（RPV），而脾静脉（SV）的大部分血液进入左门静脉（LPV）。对于患者和健康志愿者的所有PV结构，主要PV压降随SV血流速度线性增加。流量比Q/Q随着体积比V/V的增加而增加，呈现线性相关，皮尔逊相关系数为0.93。
血液分布的差异与临床医生的认知一致，并验证了我们的模拟结果。我们证明了PV压力随SV血流速度升高而线性增加。此外，左右肝叶的体积与相应PV分支中的血流速率呈正相关。
