多模态MRI评价皮层下血管性认知功能障碍白质高信号半暗带

目的探讨不同MR成像技术评价皮层下血管性认知功能障碍(SVCI)患者脑白质高信号(WMH)半暗带(WMH-P)的价值。方法对29例SVCI患者行弥散加权成像(DTI)、三维动脉自旋标记(3D-ASL)和酰胺质子化学交换饱和转移(CEST APT)扫描及神经心理学评估。将WMH周围1 cm范围为定义WMH-P,分别测量WMH、WMH-P及WMH-P以外正常表观白质(NAWM)的各项成像参数值,并与认知评分进行相关性分析。结果FA和MD值在WMH、WMH-P及WMH-P以外NAWM之间差异均有统计学意义(P均<0.05),脑血流量(CBF)在WMH-P与WMH-P以外NAWM以及WMH与WMH-P以外NAWM之间均有统计学意义(P均<0.05)。WMH-P和WMH-P以外NAWM的FA值与MoCA评分呈显著正相关(P均<0.05)。结论DTI技术与3D-ASL能反映SVCI患者脑白质病变范围及进展趋势;WMH-P的FA值能较好地评价SVCI患者认知功能水平。

Multimodal MRI in evaluating white matter hyperintensity penumbras in patients with subcortical vascular cognitive impairment

Objective To explore the value of different MR techniques in evaluating white matter hyperintensity (WMH) penumbra (WMH-P) in patients with subcortical vascular cognitive impairment (SVCI). Methods A total of 29 SVCI patients underwent diffusion weight imaging (DTI), 3D-arterial spin labeling (3D-ASL) and chemical exchange saturation transfer amide proton transfer (CEST APT) scans as well as neuropsychological evaluation. WMH-P was defined in the range of 1 cm around WMH. Imaging parameters of WMH, WMH-P and normal appearing white matter (NAWM) outside WMH-P were measured and analyzed with cognitive scores. Results There were significant differences of FA and mean diffusivity MD values among WMH, WMH-P and NAWM outside WMH-P (all P<0.05), also of cerebral blood flow (CBF) between WMH-P and NAWM outside WMH-P, as well as between WMH and NAWM outside WMH-P (all P<0.05). FA value in WMH-P and NAWM outside WMH-P was positively correlated with Montreal cognitive assessment (MoCA) scores (all P<0.05). Conclusion 3D-ASL and DTI techniques can be used to reflect the extent and progression of white matter lesions in patients with SVCI. FA value of WMH-P can well evaluate the cognitive function of SVCI patients.