Division of Neuroradiology, Department of Radiology, Johns Hopkins University School of Medicine, 600 N. Wolfe Street/Phipps B100-D, Baltimore, MD 21287, USA.
Neuroradiology. 2011 Mar;53(3):185-91. doi: 10.1007/s00234-010-0790-6.
Extract of Ginkgo biloba (EGb), a dietary supplement used for a number of conditions including dementia, has been suggested to increase cerebral bloodflow (CBF). The purpose of this study was to determine if changes in CBF could be detected by dynamic susceptibility contrast-enhanced magnetic resonance imaging (DSC-MRI)in elderly human subjects taking EGb.
DSC-MRI was performed in nine healthy men(mean age 61±10 years) before and after 4 weeks of 60 mg EGb taken twice daily. One subject underwent six consecutive scans to evaluate intrasubject reproducibility. CBF values were computed before and after EGb, and analyzed at three different levels of spatial resolution, using voxel-based statistical parametric mapping (SPM), and regions of interest in different lobes, and all regions combined.
Normalized intrasubject CBF (nCBF) measurements had a standard deviation of 7% and 4% in gray and white matter (WM) regions, respectively. SPM using an uncorrected, voxel-level threshold of P≤0.001 showed a small CBF increase in the left parietal-occipital region.CBF in individual lobar regions did not show any significant change post-EGb, but all regions combined showed a significant increase of non-normalized CBF after EGb (15% in white and 13% in gray matter, respectively, P≤0.0001).
nCBF measured by DSC-MRI has good intrasubject reproducibility. In this small cohort of normal elderly individuals, a mild increase in CBF is found in the left parietal-occipital WM after EGb, as well as a small but statistically significant increase in global CBF.
银杏叶提取物（EGb）是一种膳食补充剂，用于多种疾病，包括痴呆症。有人认为它可以增加脑血流量（CBF）。本研究旨在确定服用 EGb 的老年健康受试者是否可以通过动态磁敏感对比增强磁共振成像（DSC-MRI）检测到 CBF 的变化。
9 名健康男性（平均年龄 61±10 岁）在每天两次服用 60mg EGb 四周前后进行 DSC-MRI。一名受试者进行了六次连续扫描以评估个体内的可重复性。在服用 EGb 前后计算 CBF 值，并使用基于体素的统计参数映射（SPM），不同脑叶的感兴趣区以及所有区域的组合，在三个不同的空间分辨率水平上进行分析。
正常化个体内 CBF（nCBF）测量在灰质和白质（WM）区域的标准偏差分别为 7%和 4%。使用未校正的体素水平阈值 P≤0.001 的 SPM 显示左侧顶枕叶区域的 CBF 略有增加。服用 EGb 后个体脑叶区域的 CBF 没有明显变化，但所有区域的组合显示 CBF 非正常增加（白质增加 15%，灰质增加 13%，均 P≤0.0001）。
DSC-MRI 测量的 nCBF 具有良好的个体内可重复性。在这个正常老年人群的小队列中，服用 EGb 后左侧顶枕叶 WM 中发现 CBF 轻度增加，并且总 CBF 出现小但具有统计学意义的增加。
