Optical Management of Blood Pressure in the hypertensive patients with cerebrovascular disease.-Split dose I-123 IMP SPECT Study-

确定高血压合并脑血管病患者的最佳血压是非常重要的。因此，PET测得的氧提取分数（OEF）被认为是最可靠的指标。然而，PET需要大量的成本和人力。我们开发了非侵入性SPECT方法，分剂量I-123 IMP SPECT，它能够估计灌注储备，即注射乙酰唑胺（PR）后CBF的增加百分比。本研究对33例CVD患者进行了PET检查，并与常规PET检查结果进行了对比分析。在第一项研究中，根据血管造影结果将MCA区域分为3组。A组为同侧ICA系统MCA重度狭窄病变（≥ 75%）区，NA组为对侧伊卡系统MCA重度狭窄病变区，NP组为双侧无病变区。结果表明，OEF与PR无相关性，而与PR有显著负相关性，与PR有显著负相关性，但与OEF无相关性。其次，我们探讨了SPECT对OEF升高的病灶进行预测的可行性，在7个OEF较高的病灶中，（> 60%），静息CBF降低，OEF降低。结果表明，PR值与OEF值无显著性差异（P> 0.05）。为此，必须考虑其他方式或临床过程。

To determine the optimal blood pressure for hypertensive patients with cerebrovascular disease (CVD) is very important. For this purpose, oxygen extraction fraction (OEF) measured by PET had been considered as the most relable index. However, PET takes lots of costs and manpower. We had developed non-invasive SPECT method, split dose I-123 IMP SPECT, which enables to estimate perfuion reserve as %increase of CBF afar acetazolamide injection (PR). In this study, the relationship between the parameters obtained by this method and those of PET study.Totlally 33 patients with CVD were investigated. In the first study, the MCA territories were divided into 3 groups by angiographic findings. Group A was consisted of the MCA areas with sever stenotic lesion (more than 75%) in the ipsilateral ICA system, Group NA in the contralateral ICA system, and Group NP with no lesions in both sides. PR of Group A was significantly decreased in comparison with that of Group NP.CBV of Group A was significantly increased compared with Group NA.There was sinificant negative correlation between CBV and PR, however, no correlation were found between OEF and PR.Secondary, we investigated the feasibility that OEF-elevated lesions were can be predicted by SPECT.In 7 lesions with more high OEF (more than 60%), decreased resting CBF and decreased OEF were shown. However, there was no significant differences in OEF between 2 groups, with and without low PR (less than 10%).In concludion, the lesions with mild insufficiency of cerebral perfusion may be detected by PR, where CBV is increased without elevation of OEF.However, to discriminate the lesion with elevated OEF from that with normal OEF was difficult. For this purpose, other modality or clinical course have to be considered.