Department of Radiology, Tokyo Medical University, Tokyo, Japan.
J Magn Reson Imaging. 2013 May;37(5):1109-14. doi: 10.1002/jmri.23907. Epub 2012 Oct 19.
To evaluate liver function obtained by tracer-kinetic modeling of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data acquired with a routine gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced protocol.
Data were acquired from 25 cases of nonchronic liver disease and 94 cases of cirrhosis. DCE-MRI was performed with a dose of 0.025 mmol/kg Gd-EOB-DTPA injected at 2 mL/sec. A 3D breath-hold sequence acquired 5 volumes of 72 slices each: precontrast, double arterial phase, portal phase, and 4-minute postcontrast. Regions of interest (ROIs) were selected semiautomatically in the aorta, portal vein, and whole liver on a middle slice. A constrained dual-inlet two-compartment uptake model was fitted to the ROI curves, producing three parameters: intracellular uptake rate (UR), extracellular volume (Ve), and arterial flow fraction (AFF).
Median UR dropped from 4.46 10(-2) min(-1) in the noncirrhosis to 3.20 in Child-Pugh A (P = 0.001), and again to 1.92 in Child-Pugh B (P < 0.0001). Median Ve dropped from 6.64 mL 100 mL(-1) in the noncirrhosis to 5.80 in Child-Pugh A (P = 0.01). Other combinations of Ve and AFF changes were not significant for any group.
UR obtained from tracer kinetic analysis of a routine DCE-MRI has the potential to become a novel index of liver function.
评估使用常规钆塞酸二钠(Gd-EOB-DTPA)增强方案获得的动态对比增强磁共振成像(DCE-MRI)数据的示踪剂动力学模型得到的肝功能。
本研究纳入了 25 例非慢性肝病患者和 94 例肝硬化患者。DCE-MRI 采用 0.025mmol/kg Gd-EOB-DTPA 以 2ml/sec 的速度静脉注射,采集 3D 屏气序列 5 个 72 层的容积,包括:平扫、双动脉期、门静脉期和 4 分钟的对比后期。在中间层面的主动脉、门静脉和全肝上半自动选择感兴趣区(ROI)。使用约束双入口两室摄取模型拟合 ROI 曲线,得出三个参数:细胞内摄取率(UR)、细胞外容积(Ve)和动脉血流分数(AFF)。
在非肝硬化患者中,UR 的中位数从 4.46 10(-2) min(-1)下降到 Child-Pugh A 级的 3.20(P=0.001),再下降到 Child-Pugh B 级的 1.92(P<0.0001)。Ve 的中位数在非肝硬化患者中从 6.64mL 100mL(-1)下降到 Child-Pugh A 级的 5.80(P=0.01)。在任何组中,Ve 和 AFF 的其他组合变化都不显著。
从常规 DCE-MRI 的示踪剂动力学分析中获得的 UR 有可能成为肝功能的一个新指标。