Abstract：
OBJECTIVE: The aim of this study was to investigate whether the spatial coefficient of variation of arterial spin labeling (ASL-CoV) acquired in clinical settings can be used to estimate decreased cerebrovascular reactivity (CVR) measured with single-photon emission computed tomography (SPECT) and acetazolamide challenge in patients with atherosclerotic stenosis of intra- or extracranial arteries.
METHODS: We evaluated the data of 27 atherosclerotic stenosis patients who underwent pseudocontinuous ASL and SPECT. After spatial normalization, regional values were measured using the distributed middle cerebral artery territorial atlas of each patient. We performed comparisons, correlations, and receiver operating characteristic (ROC) curve analyses between ASL-cerebral blood blow (CBF), ASL-CoV, SPECT-CBF and SPECT-CVR.
RESULTS: Although the ASL-CBF values were positively correlated with SPECT-CBF values (r = 0.48, 95% confidence interval (CI) = 0.28-0.64), no significant difference in ASL-CBF values was detected between regions with and without decreased CVR. However, regions with decreased CVR had significantly greater ASL-CoV values than regions without decreased CVR. SPECT-CVR was negatively correlated with ASL-CoV (ρ = -0.29, 95% CI = -0.49 - -0.06). The area under the ROC curve of ASL-CoV in predicting decreased CVR (0.66, 95% CI = 0.51-0.81) was greater than that of ASL-CBF (0.51, 95% CI = 0.34-0.68). An ASL-CoV threshold value of 42% achieved a high specificity of 0.93 (sensitivity = 0.42, positive predictive value = 0.77, and negative predictive value = 0.75).
CONCLUSIONS: ASL-CoV acquired by single postlabeling delay without an acetazolamide challenge may aid in the identification of patients with decreased CVR on SPECT.
METHODS: We evaluated the data of 27 atherosclerotic stenosis patients who underwent pseudocontinuous ASL and SPECT. After spatial normalization, regional values were measured using the distributed middle cerebral artery territorial atlas of each patient. We performed comparisons, correlations, and receiver operating characteristic (ROC) curve analyses between ASL-cerebral blood blow (CBF), ASL-CoV, SPECT-CBF and SPECT-CVR.
RESULTS: Although the ASL-CBF values were positively correlated with SPECT-CBF values (r = 0.48, 95% confidence interval (CI) = 0.28-0.64), no significant difference in ASL-CBF values was detected between regions with and without decreased CVR. However, regions with decreased CVR had significantly greater ASL-CoV values than regions without decreased CVR. SPECT-CVR was negatively correlated with ASL-CoV (ρ = -0.29, 95% CI = -0.49 - -0.06). The area under the ROC curve of ASL-CoV in predicting decreased CVR (0.66, 95% CI = 0.51-0.81) was greater than that of ASL-CBF (0.51, 95% CI = 0.34-0.68). An ASL-CoV threshold value of 42% achieved a high specificity of 0.93 (sensitivity = 0.42, positive predictive value = 0.77, and negative predictive value = 0.75).
CONCLUSIONS: ASL-CoV acquired by single postlabeling delay without an acetazolamide challenge may aid in the identification of patients with decreased CVR on SPECT.
摘要：
目的：本研究的目的是研究在临床环境中获得的动脉自旋标记（ASL-CoV）的空间变异系数是否可用于评估单光子发射计算机断层扫描（SPECT）和乙酰唑胺激发对颅内或颅外动脉粥样硬化性狭窄患者的脑血管反应性（CVR）降低。
方法：我们评估了27例动脉粥样硬化性狭窄患者接受假连续ASL和SPECT的数据。在空间归一化之后，使用每位患者的分布式大脑中动脉领土图谱测量区域值。我们进行了比较，相关性，ASL-脑血流（CBF）之间的受试者工作特征（ROC）曲线分析，ASL-CoV,SPECT-CBF和SPECT-CVR。
结果：尽管ASL-CBF值与SPECT-CBF值呈正相关（r=0.48，95％置信区间（CI）=0.28-0.64），在有和没有CVR降低的区域之间,ASL-CBF值没有检测到显著差异.然而,CVR降低的区域的ASL-CoV值显著高于CVR未降低的区域.SPECT-CVR与ASL-CoV呈负相关(ρ=-0.29,95%CI=-0.49--0.06)。ASL-CoV预测CVR降低的ROC曲线下面积(0.66,95%CI=0.51-0.81)大于ASL-CBF(0.51,95%CI=0.34-0.68)。42%的ASL-CoV阈值实现了0.93的高特异性(灵敏度=0.42,阳性预测值=0.77,阴性预测值=0.75)。
结论：在没有乙酰唑胺激发的情况下，通过单次标记后延迟获得的ASL-CoV可能有助于在SPECT上识别CVR降低的患者。
方法：我们评估了27例动脉粥样硬化性狭窄患者接受假连续ASL和SPECT的数据。在空间归一化之后，使用每位患者的分布式大脑中动脉领土图谱测量区域值。我们进行了比较，相关性，ASL-脑血流（CBF）之间的受试者工作特征（ROC）曲线分析，ASL-CoV,SPECT-CBF和SPECT-CVR。
结果：尽管ASL-CBF值与SPECT-CBF值呈正相关（r=0.48，95％置信区间（CI）=0.28-0.64），在有和没有CVR降低的区域之间,ASL-CBF值没有检测到显著差异.然而,CVR降低的区域的ASL-CoV值显著高于CVR未降低的区域.SPECT-CVR与ASL-CoV呈负相关(ρ=-0.29,95%CI=-0.49--0.06)。ASL-CoV预测CVR降低的ROC曲线下面积(0.66,95%CI=0.51-0.81)大于ASL-CBF(0.51,95%CI=0.34-0.68)。42%的ASL-CoV阈值实现了0.93的高特异性(灵敏度=0.42,阳性预测值=0.77,阴性预测值=0.75)。
结论：在没有乙酰唑胺激发的情况下，通过单次标记后延迟获得的ASL-CoV可能有助于在SPECT上识别CVR降低的患者。
