单侧大脑中动脉狭窄患者脑血管储备力的评估

Evaluation of cerebrovascular reserve in patients with unilateral middle cerebral artery stenosis

目的用单光子发射计算机断层扫描（SPECT）结合二氧化碳（c02）负荷试验评价大脑中动脉（MCA）狭窄或闭塞患者的脑血管储备力（CVR）。方法选择自2010年10月至2012年3月间在空军总院神经内科住院的MCA狭窄或闭塞患者，C02负荷试验前后分别行SPECT检查。设定12个感兴趣区（ROl），左右对称6个，计算各感兴趣区的平均局部脑血流量比值（rCBF％），比较正常侧与患侧rCBF％的差值及C0，吸人试验前后各RoI的疋BF％变化评价CVR。结果24例患者中有2例CVR正常。CO2负荷前后rCBF％均正常的ROI有121个；CO2负荷试验前rCBF％正常，负荷试验后减低的ROI有119个；C02负荷试验前rCBF％减低，负荷试验后减低更明显的ROI有12个；另有38个ROICO：负荷试验前rCBF％减低，负荷试验后较前升高。结论单侧MCA狭窄或闭塞患者中存在着CVR正常者。MCA狭窄或闭塞后脑血管对CO2负荷试验存在不同的反应性。

Objective To evaluate the cerebrovascular reserve （CVR） of patients with unilateral middle cerebral artery （MCA） steno-occlusion with single-photon emission computed tomography （SPECT） and CO2 inhalation test. Methods SPECT were performed in patients diagnosed as having unilateral MCA steno-occlusion disease in our hospital from October 2010 to March 2012. SPECT were performed in 24 unilateral MCA steno-occlusion patients before and after CO2 inhalation text. Twelve regions of interests （ROIs）, 6 in the right and 6 in the left, were chosen in each patient; the ratio of regional cerebral blood flow （rCBF%） of all ROIs were calculated, compared between the normal side and the steno-occlusive side, and before and after CO2 inhalation test for CVR. Results Two of 24 patients had normal CVR. And there were four types of cerebrovascular reactivity to CO2： the first, there were no differences ofrCBF% before and after CO2 inhalation text in 121 ROIs; the sencond, rCBF% was normal before the CO2 inhalation text and then decreased after the test in 119 ROIs; the third, rCBF% was decreased before the CO2 inhalation text and then further decreased after the text in 12 ROIs; and the forth, rCBF% was decreased before the CO2 inhalation text and increased after the text in 72 ROIs. Conclusion There is normal CVR in patients with unilateral middle cerebral artery steno-occlusion; there are four reactions for CVR in patients with unilateral middle cerebral artery steno-occlusive.