Quantitative Measurement of Brain Perfusion with Intravoxel Incoherent Motion MR Imaging
Quantitative Measurement of Brain Perfusion with Intravoxel Incoherent Motion MR Imaging
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DOI：
10.1148/radiol.12120584
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发表时间：
2012-12-01
期刊：
影响因子：
19.7
通讯作者：
Hagmann, Patric
中科院分区：
文献类型：
--
作者：
Federau, Christian;Maeder, Philippe;Hagmann, Patric
目的：评估体素不相干运动（IVIM）磁共振成像得出的灌注参数对人脑高碳酸血症引起的血管舒张和高氧合引起的血管收缩的敏感性。 材料和方法：本研究经当地伦理委员会批准，并获得所有参与者的知情同意。使用临床 3-T 系统中的标准脉冲梯度自旋回波序列 (Stejskal-Tanner) 获取图像，使用 0 至 900 秒/毫米 (2) 范围内的 16 个 b 值。对七名健康志愿者进行了检查，他们吸入了已知会改变大脑灌注的四种不同的气体混合物（纯氧、环境空气、环境空气中的 5% CO2 和环境空气中的 8% CO2）。基于IVIM双指数模型计算扩散系数(D)、伪扩散系数(D*)、灌注分数(f)和血流相关参数(fD*)图，并对四种不同气体混合物的参数图进行比较。进行配对、单尾学生 t 检验以评估统计显着性差异。结果：所有志愿者的脑实质中的信号衰减曲线呈双指数。与吸入环境空气相比，IVIM 灌注参数 D*、f 和 fD* 随着吸入 CO2 浓度的增加而增加（对于整个大脑，对于 CO2 5%，f、D* 和 fD* P = .01；对于 f，P = .02；对于 CO2 8%，D* 和 fD* P = .01），并且当参与者吸入纯氧时观察到降低的趋势（尽管 P > .05）。 D 保持总体稳定。结论：IVIM 灌注参数对高氧合诱导的血管收缩和高碳酸血症诱导的血管舒张有反应。因此，IVIM 成像被认为是量化人类大脑灌注的有效且有前途的方法。 (C) 北美放射学会，2012
Purpose: To evaluate the sensitivity of the perfusion parameters derived from Intravoxel Incoherent Motion (IVIM) MR imaging to hypercapnia-induced vasodilatation and hyperoxygenation-induced vasoconstriction in the human brain.Materials and Methods: This study was approved by the local ethics committee and informed consent was obtained from all participants. Images were acquired with a standard pulsed-gradient spin-echo sequence (Stejskal-Tanner) in a clinical 3-T system by using 16 b values ranging from 0 to 900 sec/mm(2). Seven healthy volunteers were examined while they inhaled four different gas mixtures known to modify brain perfusion (pure oxygen, ambient air, 5% CO2 in ambient air, and 8% CO2 in ambient air). Diffusion coefficient (D), pseudodiffusion coefficient (D*), perfusion fraction (f), and blood flow-related parameter (fD*) maps were calculated on the basis of the IVIM biexponential model, and the parametric maps were compared among the four different gas mixtures. Paired, one-tailed Student t tests were performed to assess for statistically significant differences.Results: Signal decay curves were biexponential in the brain parenchyma of all volunteers. When compared with inhaled ambient air, the IVIM perfusion parameters D*, f, and fD* increased as the concentration of inhaled CO2 was increased (for the entire brain, P = .01 for f, D*, and fD* for CO2 5%; P = .02 for f, and P = .01 for D* and fD* for CO2 8%), and a trend toward a reduction was observed when participants inhaled pure oxygen (although P > .05). D remained globally stable.Conclusion: The IVIM perfusion parameters were reactive to hyperoxygenation-induced vasoconstriction and hypercapnia-induced vasodilatation. Accordingly, IVIM imaging was found to be a valid and promising method to quantify brain perfusion in humans. (C) RSNA, 2012