动脉自旋标记灌注成像观察帕金森病患者皮质下脑区血流代谢

Study of the subcortical cerebral blood flow metabolism in patients with Parkinson′s disease using arterial spin labeling magnetic resonance imaging

利用磁共振动脉自旋标记成像(MRI-ASL)方法观察帕金森病患者皮质下脑区的脑血流灌注可能的变化.方法收集来自2014年10月至2016年10月江苏省苏北人民医院神经内科住院部或门诊的30例中早期帕金森病患者及40名正常受试者,均进行脑常规MRI及3D ASL成像,将ASL脑血流图匹配到标准化脑空间,利用蒙特利尔立体标准脑空间的壳核、苍白球、尾状核及丘脑模板为感兴趣区,在标准化的脑血流图上分别提取这些脑区内的平均脑血流绝对值,并计算各感兴趣区脑血流相对于受试者个体自身全脑血流量的校正比值(rCBF),采用单因素方差分析统计比较两组差异.结果帕金森病组皮质下两侧的尾状核(左侧35.32±6.47,右侧36.17±7.07)、壳核(左侧41.97± 6.12,右侧42.91±6.43)、苍白球(左侧40.42±5.83,右侧40.18±5.70)、丘脑(左侧46.58±7.71,右侧49.11± 7.10)的脑血流值(ml·100 g^-1·min^-1)均显著小于对照组(尾状核左侧41.38±7.05,右侧41.63±6.85;壳核左侧48.49±8.78,右侧48.99±8.88;苍白球左侧45.65±8.35,右侧45.53±8.94;丘脑左侧54.32±11.94,右侧56.21±11.98;F=13.58、10.56、8.59、8.23、12.11、10.06、9.57、8.30,P=0.000、0.002、0.001、0.002、0.005、0.005、0.003、0.005).帕金森病组全脑平均脑血流值(ml·100 g^-1·min^-1)也显著低于对照组(42.14± 9.61比51.59±9.67,F=16.42,P<0.01).患者组全脑血流量的平均值降低幅度为18.31%;帕金森病组几乎所有皮质下脑区的rCBF值均显著高于对照组.结论脑血流代谢灌注减低是中早期帕金森病退行性变的基本特征之一,不仅全脑血流量减低,而且皮质下脑结构脑血流量减低;但是帕金森病患者皮质下脑区表现了相对自身全脑平均水平增高的血流灌注,帕金森病患者的脑血流动力学代谢可能发生了重新分布.

Objective To investigate alterations of blood perfusion in subcortical regions in patients with Parkinson′s disease (PD) by three dimentional arterial spin labeling (ASL) magnetic resonance imaging (MRI). Methods Thirty patients with PD and 40 control subjects were recruited from the inpatient and outpatient of the Department of Neurology of Northern Jiangsu People′s Hospital during October 2014 to October 2016, and routine brain MRI and 3D pseudo-continuous pulse ASL were performed on all the subjects. The cerebral blood flow (CBF) maps derived from 3D ASL were coregistered to the Montreal Neurological Institute brain space. The stereo-templates of bilateral caudate nucleus, putamen nucleus, globus pallidum and thalamus from Anatomical Automatic Labeling were used as region of interest (ROI) to exstract absolute CBF values in these subcortical regions, respectively. The CBF ratio (rCBF) values represented by individual whole brain CBF divided by each of the regional CBF were also calculated in consideration of the difference between individual whole brain CBF. The CBF and rCBF values were compared respectively between groups by one-way analysis of variance. Results The subcortical CBF values (ml·100 g-1·min-1) for each ROI in PD (caudate nucleus (left: 35.32±6.47, right: 36.17±7.07), globus pallidum (left: 40.42 ± 5.83, right: 40.18 ± 5.70), putamen nucleus (left: 41.97 ± 6.12, right: 42.91 ± 6.43) and thalamus (left: 46.58 ± 7.71, right: 49.11 ± 7.10)) were significantly lower than that in the control group (caudate nucleus (left: 41.38±7.05,right: 41.63±6.85), globus pallidum (left: 45.65±8.35,right: 45.53±8.94), putamen nucleus (left: 48.49±8.78, right: 48.99±8.88) and thalamus (left: 54.32±11.94,right: 56.21±11.98), F=13.58, 10.56, 12.11, 10.06, 8.59, 8.23, 9.57, 8.30, P=0.000, 0.002, 0.005, 0.005, 0.001, 0.002, 0.003, 0.005, respectively ). The whole brain mean CBF values of each subject were also extracted and compared bewteen groups, and mean CBF values (ml·100 g-1·min-1) in PD patients (42.14±9.61) decreased significantly than those in the control group (51.59±9.67, F=16.42, P<0.01), and there was a 18.31% decrement in whole brain mean CBF in the patient group. However, rCBF values for almost all subcortical ROIs of the patients significantly increased when compared with the control group. Conclusions The decreased absolute cerebral blood perfusion involved not only subcortical regions, but also the whole brain level in the course of PD. The CBF metabolism in patients with PD may have been redistributed, with relative hyperperfusion in the subcortical brain regions contrast to the whole brain perfusion level of patients themselves.