背景经皮肝穿刺门静脉（PV）栓塞（PVE）是晚期胆道癌当未来肝残余（FLR）不足时的标准术前手术，但该手术对门静脉血流动力学的影响仍不清楚。目的 评估四维 (4D) MRI 流量计是否可用于估计 FLR 体积并确定该测量的最佳时间。材组）或 PVE 后 3-4 天（3 天组）。在 PVE 前和 PVE 后但手术前使用 CT 测量 FLR 体积。通过 Wilcoxon 符号秩检验以及 Spearman 秩相关分析血流变化。结果 0 天组包括 24 名参与者（中位年龄 72 岁 [IQR，69-77 岁]；17 名男性参与者），3 天组包括 13 名参与者（中位年龄 71 岁 [IQR，68-78 岁]）年]；八名男性参与者）。 PVE 后两组的左 PV (LPV) 流速均有所增加（0 天组：从中值 3.72 mL/秒 [IQR，2.83-4.55 mL/秒] 增加至 9.48 mL/秒 [IQR，8.12-10.7 mL/秒] ，P < .001；3 天组：从中位数 3.65 mL/sec [IQR，2.14-3.79 mL/sec] 到 8.16 mL/sec [IQR，6.82-8.98 mL/sec]，P < .001）。仅在 3 天组中，LPV 流量变化与 FLR 体积变化相关（相对于从 PVE 到术前 CT 的天数）（ρ = 0.62，P = .02；0 天组，P = .11）。用于估计术前 FLR 体积的回归方程的输出与 CT 测量体积相关 (ρ = 0.78；P = .002)。结论 四维血流 MRI 显示 PVE 后 3-4 天残余门静脉分支血流量增加，为估计术前 FLR 体积提供了见解。根据 CC BY 4.0 许可证发布。本文提供了补充材料。另请参阅本期 Roldán-Alzate 和 Oechtering 的社论。

Background Percutaneous transhepatic portal vein (PV) embolization (PVE) is a standard preoperative procedure for advanced biliary cancer when the future liver remnant (FLR) is insufficient, yet the effect of this procedure on portal hemodynamics is still unclear. Purpose To assess whether four-dimensional (4D) MRI flowmetry can be used to estimate FLR volume and to identify the optimal time for this measurement. Materials and Methods This prospective single-center study enrolled consecutive adult patients with biliary cancer who underwent percutaneous transhepatic PVE for the right liver between June 2020 and November 2022. Portal hemodynamics were assessed using 4D flow MRI before PVE and within 1 day (0-day group) or 3-4 days (3-day group) after PVE. FLR volume was measured using CT before PVE and after PVE but before surgery. Blood flow changes were analyzed with the Wilcoxon signed rank test, and correlations with Spearman rank correlation. Results The 0-day group included 24 participants (median age, 72 years [IQR, 69-77 years]; 17 male participants), and the 3-day group included 13 participants (median age, 71 years [IQR, 68-78 years]; eight male participants). Both groups showed increased left PV (LPV) flow rate after PVE (0-day group: from median 3.72 mL/sec [IQR, 2.83-4.55 mL/sec] to 9.48 mL/sec [IQR, 8.12-10.7 mL/sec], P < .001; 3-day group: from median 3.65 mL/sec [IQR, 2.14-3.79 mL/sec] to 8.16 mL/sec [IQR, 6.82-8.98 mL/sec], P < .001). LPV flow change correlated with FLR volume change relative to the number of days from PVE to presurgery CT only in the 3-day group (ρ = 0.62, P = .02; 0-day group, P = .11). The output of the regression equation for estimating presurgery FLR volume correlated with CT-measured volume (ρ = 0.78; P = .002). Conclusion Four-dimensional flow MRI demonstrated increased blood flow in residual portal branches 3-4 days after PVE, offering insights for estimating presurgery FLR volume. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Roldán-Alzate and Oechtering in this issue.