Measurement of vascular water transport in human subjects using time-resolved pulsed arterial spin labelling
Measurement of vascular water transport in human subjects using time-resolved pulsed arterial spin labelling
复制标题
DOI：
10.1002/nbm.3344
复制
发表时间：
2015-08-01
影响因子：
2.9
通讯作者：
Wirestam, Ronnie
中科院分区：
文献类型：
--
作者：
Bibic, Adnan;Knutsson, Linda;Wirestam, Ronnie
大多数动脉自旋标记 (ASL) 数据分析方法旨在提供脑血流量 (CBF) 的定量测量。然而，本研究的重点是测量血水通过毛细血管到实质的传输时间（称为毛细血管传输时间，CTT），作为表征系统血液动力学的替代参数。所采用的方法基于非房室模型，并且不需要将测量添加到常见的时间分辨 ASL 实验中。势中标记自旋的布朗运动以一维广义朗之万方程为起点，以福克-普朗克微分方程描述标记自旋在终点的平均分布，该微分方程考虑了微脉管系统和跨毛细血管渗透性的伪随机性质对标记水的流动和分散的影响。在重测设计中，使用脉冲 ASL 序列以及三维梯度和自旋回波 (3D-GRASE) 读数，两次采集了 14 名健康受试者的多反转时间 (multi-TI) ASL 数据。基于误差分析来预测获得相当精确的参数估计所需的感兴趣区域 (ROI) 的大小，对两个相对较大的 ROI（即枕叶 (OC) 和岛叶皮质 (IC)）中的数据进行了分析。第一次实验中 OC 中的 CTT 平均值为 260 +/- 60ms，第二次实验中为 270 +/- 60ms。相应的 IC 值分别为 460 +/- 130ms 和 420 +/- 139ms。与水转移时间相关的信息对于以血脑屏障破坏或毛细血管血流紊乱为特征的脑部病症或疾病的诊断和随访可能很重要。版权所有 (c) 2015 约翰·威利父子有限公司
Most approaches to arterial spin labelling (ASL) data analysis aim to provide a quantitative measure of the cerebral blood flow (CBF). This study, however, focuses on the measurement of the transfer time of blood water through the capillaries to the parenchyma (referred to as the capillary transfer time, CTT) as an alternative parameter to characterise the haemodynamics of the system. The method employed is based on a non-compartmental model, and no measurements need to be added to a common time-resolved ASL experiment. Brownian motion of labelled spins in a potential was described by a one-dimensional general Langevin equation as the starting point, and as a Fokker-Planck differential equation for the averaged distribution of labelled spins at the end point, which takes into account the effects of flow and dispersion of labelled water by the pseudorandom nature of the microvasculature and the transcapillary permeability. Multi-inversion time (multi-TI) ASL data were acquired in 14 healthy subjects on two occasions in a test-retest design, using a pulsed ASL sequence and three-dimensional gradient and spin echo (3D-GRASE) readout. Based on an error analysis to predict the size of a region of interest (ROI) required to obtain reasonably precise parameter estimates, data were analysed in two relatively large ROIs, i.e. the occipital lobe (OC) and the insular cortex (IC). The average values of CTT in OC were 260 +/- 60ms in the first experiment and 270 +/- 60ms in the second experiment. The corresponding IC values were 460 +/- 130ms and 420 +/- 139ms, respectively. Information related to the water transfer time may be important for diagnostics and follow-up of cerebral conditions or diseases characterised by a disrupted blood-brain barrier or disturbed capillary blood flow. Copyright (c) 2015 John Wiley & Sons, Ltd.