轻度认知障碍患者的SPECT与TCD脑血流改变

摘要

Objective To apply single photon emission computed tomography( SPECT )and transcranial Doppler ( TCD )to investigate the regional cerebral blood flow ( rCBF ) and brain hemodynamic changes in patients with mild cognitive impairment ( MCI ) , and to analyze the relationship between the clinical characteristics of patients and rCBF as well as the cognitive changes. Methods 30 cases of MCI group and 20 cases of control group were recruited, all subjects underwent a general examination, neuropsychological scoring, a brain SPECT perfusion imaging and TCD examination. Results Compared with the control group, the rCBF in the bilateral frontal lobe, the left parietal lobe and the bilateral interior temporal in the MCI group were significantly reduced( P <0. 05 ,P <0. 01 ). Within the group of MCI, the rCBF of the left frontal, left superior parietal lobule, and left temporal lobe were significantly reduced compared with the right corresponding parts( P <0. 01 ). The incidence of one or more abnormal TCD hemodynamics parameter increased significantly in the MCI group ( 60% ) compared with the control group (20% )( x2 =5. 92, P <0. 05 ), the peak flow velocity( Vp ) and mean flow velocity( Vm ) in the middle cerebral artery( MCA ) and anterior cerebral artery( AC A ) reduced significantly in the MCI group, and the systolic-diastolic ratio of blood flow velocity ( S/D ), pulsatility index ( PI ) and resistance index( RI ) increased significantly too ( P <0. 05 ). Conclusion Abnormality of rCBF and hemodynamics occured in patients with MCI, SPECT and TCD have important value in detection of MCI.%目的 应用单光子发射计算机断层核素显像(SPECT)以及经颅多普勒(TCD)检查轻度认知障碍(MCI)患者的局部脑血流量(rCBF)以及脑血流动力学改变,并分析患者的临床特征以及认知改变与脑血流之间的关系.方法 MCI患者30例,记为MCI组,健康体验者20例,记为对照组.所有研究对象均进行一般检查、神经心理评分及SPECT脑显像和TCD检查.结果 MCI组与对照组相比,双侧额叶、左侧顶叶、双侧颞叶内侧rCBF明显降低(P<0.05,P<0.01).MCI组两侧脑区rCBF比较,左侧顶上小叶、左侧颞叶内侧均较右侧对应区域明显降低(P<0.01).MCI组中TCD存在一项或多项血流动力学异常的发生率明显增加(60.0%),而对照组仅为25.0%,差异有统计学意义(χ2=5.92,P<0.05).MCI组大脑中动脉(MCA)、大脑前动脉(ACA)的峰值流速(Vp)、均值流速(Vm)减低,收缩-舒张期血流速度比值(S/D)、搏动指数(PI) 以及阻力指数(RI)明显增加,差异有统计学意义(P<0.05).结论 MCI患者存在rCBF以及血流动力学异常,SPECT及TCD检测对于MCI的诊断有一定的价值.