...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>NMR in biomedicine >Three-dimensional whole-brain perfusion quantification using pseudo-continuous arterial spin labeling MRI at multiple postlabeling delays: accounting for both arterial transit time and impulse response function
【24h】

Three-dimensional whole-brain perfusion quantification using pseudo-continuous arterial spin labeling MRI at multiple postlabeling delays: accounting for both arterial transit time and impulse response function

机译：在多个贴标后延迟时使用伪连续动脉自旋标记MRI进行三维全脑灌注定量：考虑了动脉穿越时间和冲动响应功能

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Measurement of the cerebral blood flow (CBF) with whole-brain coverage is challenging in terms of both acquisition and quantitative analysis. In order to fit arterial spin labeling-based perfusion kinetic curves, an empirical three-parametermodel which characterizes the effective impulse response function (IRF) is introduced, which allows the determination of CBF, the arterial transit time (ATT) and T_(1,eff). The accuracy and precision of the proposed model were compared with those of more complicated models with four or five parameters through Monte Carlo simulations. Pseudo-continuous arterial spin labeling images were acquired on a clinical 3-T scanner in 10 normal volunteers using a three-dimensional multi-shot gradient and spin echo scheme at multiple post-labeling delays to sample the kinetic curves. Voxel-wise fitting was performed using the three-parametermodel and othermodels that contain two, four or five unknown parameters. For the two-parametermodel, T_(1,eff) values close to tissue and blood were assumed separately. Standard statistical analysis was conducted to compare these fitting models in various brain regions. The fitted results indicated that: (i) the estimated CBF values using the two-parameter model show appreciable dependence on the assumed T_(1,eff) values; (ii) the proposed three-parametermodel achieves the optimal balance between the goodness of fit and model complexitywhen compared among the models with explicit IRF fitting; (iii) both the two-parameter model using fixed blood T_1 values for T_(1,eff) and the three-parameter model provide reasonable fitting results. Using the proposed three-parameter model, the estimated CBF (46±14 mL/100 g/min) and ATT (1.4±0.3 s) values averaged from different brain regions are close to the literature reports; the estimated T_(1,eff) values (1.9±0.4 s) are higher than the tissue T_1 values, possibly reflecting a contribution from the microvascular arterial blood compartment.
机译：在采集和定量分析方面，具有全脑覆盖范围的脑血流量（CBF）的测量具有挑战性。为了拟合基于动脉自旋标记的灌注动力学曲线，引入了表征有效脉冲响应函数（IRF）的经验三参数模型，该模型可以确定CBF，动脉渡越时间（ATT）和T_（1， eff）。通过蒙特卡洛模拟，将提出的模型的准确性和精密度与具有四个或五个参数的较复杂模型的准确性和精密度进行了比较。伪连续动脉自旋标记图像是在10名正常志愿者的临床3-T扫描仪上使用三维多重梯度和自旋回波方案在多个标记后延迟采集的，以采集动力学曲线。使用三参数模型和包含两个，四个或五个未知参数的其他模型进行按体素拟合。对于两参数模型，分别假设接近组织和血液的T_（1，eff）值。进行了标准统计分析，以比较各个大脑区域的这些拟合模型。拟合结果表明：（i）使用两参数模型估算的CBF值显示出对假设的T_（1，eff）值的明显依赖; （ii）与具有显式IRF拟合的模型相比，拟议的三参数模型在拟合优度和模型复杂性之间实现了最佳平衡; （iii）使用固定血液T_1值的T_（1，eff）的两参数模型和三参数模型均提供了合理的拟合结果。使用建议的三参数模型，从不同大脑区域获得的平均CBF（46±14 mL / 100 g / min）和ATT（1.4±0.3 s）估计值接近文献报道。估计的T_（1，eff）值（1.9±0.4 s）高于组织T_1值，可能反映了微血管动脉血室的贡献。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号