Knapp W H, von Kummer R, Kübler W
J Nucl Med. 1986 Apr;27(4):465-70.
The ratio between cerebral blood flow (CBF) and cerebral blood volume (CBV) has been proposed as an adequate parameter for the evaluation of cerebrovascular disease (CVD), but to date it has not been assessed with SPECT. We have chosen [123I]IMP for CBF and [99mTc] erythrocytes for CBV imaging. The distribution of both nuclides was investigated in succession using corrections for the contamination of the 99mTc tomograms by 123I. The ratio between 123I and 99mTc tomograms yielded the CBF/CBV distribution. Quantitation was obtained by side-to-side comparison of both hemispheres and of segments containing the territories affected by CVD. In 16 patients with CVD, CBF of the affected territories was 85 +/- 19% (s.d.) when related to the nonsymptomatic contralateral side (100%). When the regions of interest defined within one slice encompassed the entire affected hemisphere, the average CBF was 95 +/- 9%, again related to the nonsymptomatic side. The corresponding CBF/CBV data in 15 of these 16 patients were 60 +/- 32% and 81 +/- 16%. In unilateral internal carotid artery stenoses greater than 50% (N = 10), segmental CBF averaged 81.1 +/- 10.1% and CBF/CBV 49.6 +/- 15.5% relative to the contralateral side. The figures for the hemispheres were 92.8 +/- 5.8 and 75.8 +/- 12.6, respectively. These clinical findings mirror the characteristics of CBF autoregulation, namely the vasodilation of small vessels in decreased arterial perfusion pressure. They, therefore, substantiate SPECT imaging of CBF/CBV for the assessment of cerebral perfusion reserve in CVD.
脑血流量（CBF）与脑血容量（CBV）之比已被提议作为评估脑血管疾病（CVD）的一个适当参数，但迄今为止尚未用单光子发射计算机断层显像（SPECT）进行评估。我们选择了用于CBF显像的[123I]异丁基异丙基胍（IMP）和用于CBV显像的[99mTc]红细胞。利用对123I对99mTc断层图像污染的校正，相继研究了两种核素的分布情况。123I与99mTc断层图像之比得出CBF/CBV分布。通过对两个半球以及包含受CVD影响区域的节段进行左右对比来进行定量分析。在16例CVD患者中，与无症状的对侧（100%）相比，受累区域的CBF为85±19%（标准差）。当在一个层面内定义的感兴趣区域涵盖整个受累半球时，平均CBF为95±9%，同样与无症状侧相关。这16例患者中有15例的相应CBF/CBV数据分别为60±32%和81±16%。在单侧颈内动脉狭窄大于50%的患者（N = 10）中，相对于对侧，节段性CBF平均为81.1±10.1%，CBF/CBV为49.6±15.5%。半球的相应数值分别为92.8±5.8和75.8±12.6。这些临床发现反映了CBF自动调节的特征，即动脉灌注压降低时小血管的血管舒张。因此，它们证实了SPECT对CBF/CBV成像用于评估CVD中脑灌注储备的价值。
