Estimation of cerebral perfusion reserve by blood oxygenation level-dependent imaging: Comparison with single-photon emission computed tomography
Estimation of cerebral perfusion reserve by blood oxygenation level-dependent imaging: Comparison with single-photon emission computed tomography
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DOI：
10.1097/01.wcb.0000037546.46809.ca
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发表时间：
2003-01-01
影响因子：
6.3
通讯作者：
Inubushi, T
中科院分区：
文献类型：
--
作者：
Shiino, A;Morita, Y;Inubushi, T
脑血管储备能力的测量可预测大血管闭塞患者发生缺血性损伤的风险。血氧水平依赖性（BOLD）成像有可能根据反映血管内氧合血红蛋白和脱氧血红蛋白磁化率差异的信号变化，无创地估计脑循环的储备能力。作者通过将结果与现有的 CBF 测量方法进行比较，探讨了使用 BOLD 技术评估脑血管闭塞性疾病患者脑血管储备能力的可行性。将 10 名颈内动脉严重或完全闭塞的患者与 17 名健康受试者进行比较，以评估区域差异并确定表明 BOLD 信号变化的变量。通过屏气诱导脑血管扩张，并通过梯度回波、平面回波成像检查 R-2* 变化。在测量 BOLD 信号的区域变化之前，通过移动正弦波模板的相位来校正“激活”和“休息”周期的实际时序以获得最大相关系数。在逐个像素的基础上计算信号变化百分比，并与乙酰唑胺攻击前后通过单光子发射计算机断层扫描 (SPECT) 测量的 CBF 进行比较。 BOLD研究检测到的损伤程度和损伤区域的分布与SPECT结果相关。通过目视检查的 BOLD 技术的总体敏感性和特异性分别为 100% 和 98.4%。在储备能力耗尽的地区经常观察到负面反应（CBF下降），表明存在“偷窃”现象。百分比变化和 DeltaCBF 具有良好的相关性 (P < 0.01)。大多数储备能力受损区域的平均百分比变化比健康受试者的平均值低 2 个标准差以上。本发明的半定量 BOLD 分析方法可用于创建脑血流动力学状态图。此外，用于评估脑血流动力学的可靠且普遍可用的技术的发展为监测和治疗储备受损患者的临床研究打开了大门。本研究就是尝试进行此类分析。
Measurement of cerebrovascular reserve capacity predicts the risk of ischemic insult in patients with major vessel occlusion. Blood oxygenation level-dependent (BOLD) imaging has the potential to estimate reserve capacity of the cerebral circulation noninvasively based on changes in the signal that reflect differences in the magnetic susceptibility of intravascular oxyhemoglobin and deoxyhemoglobin. The authors examined the feasibility of using the BOLD technique to assess cerebrovascular reserve capacity in patients with cerebrovascular occlusive disease by comparing results with an established method of measuring CBF. Ten patients with severe or complete occlusion of the internal carotid artery were compared with 17 healthy subjects to evaluate regional differences and identify variables that indicate a change in the BOLD signal. Dilation of cerebral vessels was induced by breath holding, and the R-2* change was examined with gradient-echo, echo-planar imaging. Before measuring the regional change in the BOLD signal, actual timing of "activated" and "rest" periods was corrected by shifting the phase of a sine-wave template to obtain the largest correlation coefficient. Percent signal change was calculated on a pixel-by-pixel basis and was compared with CBF measured by single-photon emission computed tomography (SPECT) before and after acetazolamide challenge. The degree of impairment and the distribution of impaired areas detected by the BOLD study correlated with the results of SPECT. Overall sensitivity and specificity of the BOLD technique by visual inspection were 100% and 98.4%, respectively. A negative response (decreased CBF) frequently was observed in areas of exhausted reserve capacity, suggesting that a "steal" phenomenon exists. The percent change and the DeltaCBF were well correlated (P < 0.01). The mean percent change in most areas of impaired reserve capacity was more than 2 SD below the mean values in healthy subjects. The present method of semiquantitative BOLD analysis can be used to create a map of the cerebral hemodynamic state. Furthermore, the development of reliable, generally accessible techniques for evaluating cerebral hemodynamics opens the door for clinical studies to monitor and treat patients with compromised reserve. This study is an attempt to develop such analysis.