A new method for quantitative regional cerebral blood volume measurements using computed tomography.
A new method for quantitative regional cerebral blood volume measurements using computed tomography.
复制标题
一种使用计算机断层扫描定量局部脑血容量测量的新方法。
DOI：
10.1161/01.str.28.10.1998
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发表时间：
1997
期刊：
影响因子：
8.3
通讯作者：
Schröder,ML
中科院分区：
文献类型：
--
作者：
Muizelaar,JP;Fatouros,PP;Schröder,ML
背景和目的脑血容量（CBV）的知识是非常宝贵的，以确定脑肿胀的主要原因，在中风或重型颅脑损伤患者，它也可能有助于临床决策，认为有血流动力学短暂性脑缺血发作（TIA）的患者。这项调查是关于定量区域CBV measurements.MethodsThe技术的发展和临床应用的一种新方法是基于连续测量脑血流量（CBF）氙/CT和组织平均通过时间（MTT）的动态CT快速碘造影剂团注后。CBV图是根据中央容积原理通过CBF和MTT图相乘产生的：CBV=CBF×MTT。该方法是快速和容易实现的CT扫描仪与氙气/CBF的能力。它产生CBV值表示在每100克tissue.ResultsThe方法的血液毫升数进行了验证，在控制的生理条件下，造成的变化，确定与我们的技术和压力-容积指数（PVI）测量。CBV变化的两个独立估计值在15%以内一致。在正常志愿者中使用这种方法进行CBV测量，以建立基线值，并与使用面积比方法计算CBF和CBV的值进行比较。平均CBV为5.3 mL/100 g。结论本研究的主要结论是：（1）所提出的CBV测量方法准确地反映了CBV的变化，（2）MTT×CBF的测定结果与面积比法测量正常志愿者CBV的结果一致，并与文献报道的其他方法一致;（3）重型颅脑损伤后早期MTT明显延长，结合脑血流量下降和动静脉血氧分压差增加，提示脑血管阻力增加，与早期缺血一致，微循环狭窄;（4）TIA患者颈内动脉闭塞半球CBV增加，表明代偿性血管舒张和可能的血液动力学原因。
Background and PurposeKnowledge of cerebral blood volume (CBV) is invaluable in identifying the primary cause of brain swelling in patients with stroke or severe head injury, and it might also help in clinical decision making in patients thought to have hemodynamic transient ischemic attacks (TIAs). This investigation is concerned with the development and clinical application of a new method for quantitative regional CBV measurements.MethodsThe technique is based on consecutive measurements of cerebral blood flow (CBF) by xenon/CT and tissue mean transit time (MTT) by dynamic CT after a rapid iodinated contrast bolus injection. CBV maps are produced by multiplication of the CBF and MTT maps in accordance with the Central Volume Principle: CBV=CBF×MTT. The method is rapid and easily implemented on CT scanners with the xenon/CBF capability. It yields CBV values expressed in milliliters of blood per 100 grams of tissue.ResultsThe method was validated under controlled physiological conditions causing changes that were determined both with our technique and from pressure-volume index (PVI) measurements. The two independent estimates of CBV changes were in agreement within 15%. CBV measurements using this method were carried out in normal volunteers to establish baseline values and to compare with values using the ratio-of-areas method for calculating both CBF and CBV from the dynamic study alone. Average CBV was 5.3 mL/100 g. The method was also applied in 71 patients with severe head injuries and in 1 patient with hemodynamic TIAs.ConclusionsThe primary conclusions from this study were (1) the proposed method for measuring CBV accurately determines changes in CBV; (2) the MTT×CBF determinations are in agreement with the ratio-of-areas method for CBV measurements in normal volunteers and are consistent with other methods reported in the literature; (3) MTTs are significantly prolonged early after severe head injury, which when combined with the finding of decreased CBF and increased arteriovenous difference of oxygen indicates increased cerebrovascular resistance due to narrowing of the microcirculation consistent with the presence of early ischemia; and (4) CBV in the patient with TIAs was increased in the hemisphere with the occluded internal carotid artery, indicating compensatory vasodilation and probable hemodynamic cause.