背景:小脑横裂(CCD)是指小脑半球对侧幕上疾病的灌注和代谢下降。对脑血管反应性(CVR)中CCD的先前研究仅限于最终CVR估计(CVRend)。我们最近使用动态CVR分析证明了非持续CVR最大值(CVRmax)的存在,为血液动力学刺激提供CVR的完全动态表征。
目的:从动态血氧水平依赖性(BOLD)MRI研究CVRmax中的CCD,通过与传统CVRend估计的比较。
方法:回顾性。
方法:共有23例患者(中位年龄:51岁,10名女性)患有单侧慢性狭窄闭塞性脑血管病,没有CCD状态的先验知识。
■A3-T,T1加权磁化准备的快速梯度回波(MPRAGE)和乙酰唑胺增强的BOLD成像使用梯度回波回波平面成像(EPI)序列进行。
结果:使用自定义去噪管道生成BOLD-CVR时间信号。使用相对于第一分钟基线的BOLD响应的最后一分钟建立CVRend。根据健康与患病大脑半球的分类,计算双侧大脑和小脑半球的CVRmax和CVRend。三个独立的观察者评估了CCD存在的所有数据。
方法:比较半球CVR的皮尔逊相关性,用于比较CCD患病率的两比例Z检验,和Wilcoxon符号秩检验比较中位数CVR。有统计学意义的水平设为P≤0.05。
结果:在CVRend和CVRmax图中观察到与CCD相关的变化,所有CCD+病例可通过检查任一张地图来识别。与CVRmax(r=0.676)相比,使用CVRend(r=0.728)时,CCD患者的大脑和对侧小脑半球CVR相关性更强。CVRmax(r=0.739)的健康大脑半球与对侧小脑半球之间的CVR相关性强于CVRend(r=0.705)。
结论:在CVR检查中可以观察到与CCD相关的改变。传统的CVRend可能会低估CVR,并可能夸大CCD。
方法:4.
■第三阶段。
Crossed cerebellar diaschisis (CCD) refers to depressions in perfusion and metabolism within the cerebellar hemisphere contralateral to supratentorial disease. Prior investigation into CCD in cerebrovascular reactivity (
CVR) has been limited to terminal
CVR estimations (CVRend ). We recently have demonstrated the presence of unsustained
CVR maxima (CVRmax ) using dynamic
CVR analysis, offering a fully dynamic characterization of
CVR to hemodynamic stimuli.
To investigate CCD in CVRmax from dynamic blood oxygen level-dependent (BOLD) MRI, by comparison with conventional CVRend estimation.
Retrospective.
A total of 23 patients (median age: 51 years, 10 females) with unilateral chronic steno-occlusive cerebrovascular disease, without prior knowledge of CCD status.
A 3-T, T1-weighted magnetization-prepared rapid gradient-echo (MPRAGE) and acetazolamide-augmented BOLD imaging performed with a gradient-echo echo-planar imaging (EPI) sequence.
A custom denoising pipeline was used to generate BOLD-CVR time signals. CVRend was established using the last minute of the BOLD response relative to the first-minute baseline. Following classification of healthy versus diseased cerebral hemispheres, CVRmax and CVRend were calculated for bilateral cerebral and cerebellar hemispheres. Three independent observers evaluated all data for the presence of CCD.
Pearson correlations for comparing CVR across hemispheres, two-proportion Z-tests for comparing CCD prevalence, and Wilcoxon signed-rank tests for comparing median
CVR. The level of statistical significance was set at P ≤ 0.05.
CCD-related changes were observed on both CVRend and CVRmax maps, with all CCD+ cases identifiable by inspection of either map. Diseased cerebral and contralateral cerebellar hemispheric CVR correlations in CCD+ patients were stronger when using CVRend (r = 0.728) as compared to CVRmax (r = 0.676). CVR correlations between healthy cerebral hemispheres and contralateral cerebellar hemispheres were stronger for CVRmax (r = 0.739) than for CVRend (r = 0.705).
CCD-related alterations could be observed in
CVR examinations. Conventional CVRend may underestimate CVR and could exaggerate CCD.
4.
Stage 3.