无症状血管性脑白质病变中的 MTT 和血脑屏障破坏。
MTT and Blood-Brain Barrier Disruption within Asymptomatic Vascular WM Lesions.
机构信息
From the Department of Electrical and Computer Engineering (B.E.D., J.L.P.), Johns Hopkins University, Baltimore, Maryland.
F.M. Kirby Research Center for Functional Brain Imaging (B.E.D., X.X., P.B.B., P.C.M.v.Z.), Kennedy Krieger Institute, Baltimore, Maryland.
出版信息
AJNR Am J Neuroradiol. 2021 Aug;42(8):1396-1402. doi: 10.3174/ajnr.A7165. Epub 2021 Jun 3.
BACKGROUND AND PURPOSE
White matter lesions of presumed ischemic origin are associated with progressive cognitive impairment and impaired BBB function. Studying the longitudinal effects of white matter lesion biomarkers that measure changes in perfusion and BBB patency within white matter lesions is required for long-term studies of lesion progression. We studied perfusion and BBB disruption within white matter lesions in asymptomatic subjects.
MATERIALS AND METHODS
Anatomic imaging was followed by consecutive dynamic contrast-enhanced and DSC imaging. White matter lesions in 21 asymptomatic individuals were determined using a Subject-Specific Sparse Dictionary Learning algorithm with manual correction. Perfusion-related parameters including CBF, MTT, the BBB leakage parameter, and volume transfer constant were determined.
RESULTS
MTT was significantly prolonged (7.88 [SD, 1.03] seconds) within white matter lesions compared with normal-appearing white (7.29 [SD, 1.14] seconds) and gray matter (6.67 [SD, 1.35] seconds). The volume transfer constant, measured by dynamic contrast-enhanced imaging, was significantly elevated (0.013 [SD, 0.017] minutes) in white matter lesions compared with normal-appearing white matter (0.007 [SD, 0.011] minutes). BBB disruption within white matter lesions was detected relative to normal white and gray matter using the DSC-BBB leakage parameter method so that increasing BBB disruption correlated with increasing white matter lesion volume (Spearman correlation coefficient = 0.44; < .046).
CONCLUSIONS
A dual-contrast-injection MR imaging protocol combined with a 3D automated segmentation analysis pipeline was used to assess BBB disruption in white matter lesions on the basis of quantitative perfusion measures including the volume transfer constant (dynamic contrast-enhanced imaging), the BBB leakage parameter (DSC), and MTT (DSC). This protocol was able to detect early pathologic changes in otherwise healthy individuals.
背景与目的
推测由缺血引起的脑白质病变与认知功能进行性损害和血脑屏障（BBB）功能障碍有关。需要研究测量脑白质病变内灌注和 BBB 通透性变化的脑白质病变生物标志物的纵向效应，以进行病变进展的长期研究。我们研究了无症状受试者脑白质病变内的灌注和 BBB 破坏情况。
材料与方法
在进行解剖成像后，连续进行动态对比增强和 DSC 成像。使用基于稀疏字典学习的受试者特定算法确定 21 名无症状个体的脑白质病变，该算法结合了手动校正。确定了包括 CBF、MTT、BBB 渗漏参数和容积转移常数在内的灌注相关参数。
结果
与正常外观的白质（7.29 [SD，1.14] 秒）和灰质（6.67 [SD，1.35] 秒）相比，脑白质病变内的 MTT 明显延长（7.88 [SD，1.03] 秒）。通过动态对比增强成像测量的容积转移常数在脑白质病变中明显升高（0.013 [SD，0.017] 分钟），与正常外观的白质相比（0.007 [SD，0.011] 分钟）。通过 DSC-BBB 渗漏参数方法，相对于正常白质和灰质检测到脑白质病变内的 BBB 破坏，即随着 BBB 破坏的增加，脑白质病变体积增加（Spearman 相关系数=0.44； <.046）。
结论
使用双重对比注射磁共振成像方案结合 3D 自动分割分析管道，根据包括容积转移常数（动态对比增强成像）、BBB 渗漏参数（DSC）和 MTT（DSC）在内的定量灌注测量值评估脑白质病变中的 BBB 破坏。该方案能够在其他健康个体中检测到早期的病理变化。
Zotero 插件