Evaluation of intraportal blood flow distribution by four dimensional MR blood flow mapping using subsecond MR imaging

使用选择性反转恢复标记脉冲进行TrueFISP MR成像，以评价来自上级肠系膜静脉和脾静脉的门静脉内血流分布。标记的血流进入门静脉显示为门静脉中信号强度降低的区域。TrueFISP MR图像垂直于门静脉获得，可以三维观察门静脉内血流分布。在正常受试者的研究中，来自上级肠系膜静脉和脾静脉的血流在一半受试者中形成流线型流动，但在垂直于门静脉获得的TrueFISP MR图像上，在其余受试者中显示门静脉中的旋转流动。垂直于门静脉的TrueFISP MR成像实现了高空间和高对比度分辨率成像，并允许详细评价门静脉内血流分布。在我们的分析中，从SMV到门静脉的暗流入信号是 ...更多信息 垂直于门静脉的斜位MR图像上，71%位于门静脉右侧下部，29%位于门静脉中部，36%位于门静脉右侧上部。在门静脉左侧下部观察到79%的SpV暗流入信号，而在门静脉上部观察到71%的SpV中心区域。在垂直门静脉的斜位图像上，57%的患者可观察到门静脉内的旋转血流，而在冠状位图像上则未观察到。此外，四维血流标测可以通过使用sebsecond超快MR成像的串行数据采集来执行。在肝硬化或慢性肝炎患者中，门静脉内常出现漩涡状血流，可能与脾静脉血流量增加有关。脾静脉与上级肠系膜静脉汇合方式的解剖学差异也可能与涡流有关。在评价禁食和进食对门静脉血流动力学的影响时，我们发现餐前门静脉主要由脾静脉血流灌注，餐后门静脉主要由上级肠系膜静脉血流灌注。此外，与空腹状态相比，餐后上级肠系膜静脉血流量显著增加，而脾静脉血流量在41%的受试者中减少，在31%的受试者中增加，在28%的受试者中没有变化。少

TrueFISP MR imaging using a selective inversion recovery tagging pulse was performed to evaluate the intraportal venous flow distribution from the superior mesenteric vein and the splenic vein. Tagged blood flow into the portal vein was shown as areas of decreased signal intensity in the portal vein. TrueFISP MR images obtained perpendicular to the portal vein allowed three-dimensional observation of intraportal venous flow distribution. In the study of normal subjects, the blood flow from the superior mesenteric vein and the splenic vein formed streamelined flow in the half of the subjects, but it showed whirled flow in the portal vein in the remaining subjects on the trueFISP MR images obtained perpendicular to the portal vein. TrueFISP MR imaging perpendicular to the portal vein achieved high spatial and high contrast resolution imaging and allowed detailed evaluation of the intraportal venous flow distribution. In our analysis, dark inflow signal to the portal vein from the SMV was … More observed in the right side of the portal vein in 71% at the lower portion while it was seen in the central area of the portal vein in 29% and in the right side in 36% at the upper portion on the oblique MR images perpendicular to the portal vein. Dark inflow signal from the SpV was observed in the left side of the portal vein in 79% at the lower portion while it was seen in the central area of the portal vein in 71% at the upper portion. Whirling flow in the portal vein was observed in 57% on the oblique MR images perpendicular to the portal vein while it was not seen on the coronal MR images. Additionally, four-dimensional blood flow mapping can be performed by serial data acquisition using sebsecond ultrafast MR imaging. In patients with cirrhosis or chronic hepatitis, the whirled flow in the portal vein was often observed probably due to the increased splenic venous flow. The whirled flow may also be associated with the anatomical variations of confluent patterns between the splenic vein and the superior mesenteric vein. In evaluating the influence of fasting and food intake for the portal flow dynamics, we revealed that the portal vein was predominantly perfused by the splenic venous flow before meal while it was predominantly perfused by the superior mesenteric venous flow after meal. Additionally, the superior mesenteric venous flow dramatically increased after meal compared with the fasting state while the splenic venous flow decreased in 41%, increased in 31% and showed no change in 28% of the subjects. Less