METHODS: Nineteen patients with Parkinson disease with mild cognitive impairment and 18 patients with Parkinson disease with dementia were prospectively enrolled. All participants underwent MR examination with 3D-T1-weighted image and diffusional kurtosis imaging sequences. Demographic data were compared between the 2 groups. Voxelwise statistical analyses of diffusional kurtosis imaging parameters were performed using tract-based spatial statistics. The receiver operator characteristic curve of significantly different metrics was graphed. The correlation of significantly different metrics with global cognitive status was analyzed.
RESULTS: Compared with the Parkinson disease with mild cognitive impairment group, the fractional anisotropy and mean kurtosis values decreased in 4 independent clusters in the forceps minor, forceps major, inferior fronto-occipital fasciculus, and the inferior and superior longitudinal fasciculus in patients with Parkinson disease with dementia; the mean diffusivity decreased in 1 cluster in the forceps minor. The fractional anisotropy value in the inferior fronto-occipital fasciculus and inferior longitudinal fasciculus would be the diffusional kurtosis imaging marker for the differential diagnosis of Parkinson disease with mild cognitive impairment and patients with Parkinson disease with dementia, with the best diagnostic efficiency of 0.853. The fractional anisotropy values in the forceps minor (β = 84.20, P < .001) and years of education (β = 0.38, P = .014) were positively correlated with the Montreal Cognitive Assessment.
CONCLUSIONS: The diffusional kurtosis imaging-derived fractional anisotropy and mean kurtosis can detect the different white matter damage patterns of Parkinson disease with mild cognitive impairment and Parkinson disease with dementia. Fractional anisotropy is more sensitive than mean kurtosis in the differential diagnosis; fractional anisotropy derived from diffusional kurtosis imaging could become a promising imaging marker for the differential diagnosis of Parkinson disease with mild cognitive impairment and Parkinson disease with dementia.
方法:前瞻性纳入19例帕金森病伴轻度认知障碍患者和18例帕金森病伴痴呆患者。所有参与者均接受了3D-T1加权图像和扩散峰度成像序列的MR检查。比较两组人口统计学数据。使用基于道的空间统计信息对扩散峰度成像参数进行了体素统计分析。绘制了明显不同度量的接收器操作员特征曲线。分析了显著不同指标与整体认知状态的相关性。
结果:与帕金森病伴轻度认知障碍组相比,在镊子小中,4个独立的簇中的分数各向异性和平均峰度值下降,镊子少校,下额枕骨束,帕金森病痴呆患者的下纵束和上纵束;在小镊子中,平均扩散率降低了1个簇。额枕骨下束和下纵束的部分各向异性值将是鉴别诊断轻度认知障碍的帕金森病和痴呆的帕金森病患者的扩散峰度成像标记。最佳诊断效率为0.853。钳子小部分各向异性值(β=84.20,P<.001)和受教育年限(β=0.38,P=.014)与蒙特利尔认知评估呈正相关。
结论:扩散峰度成像衍生的各向异性分数和平均峰度可以检测帕金森病伴轻度认知障碍和帕金森病伴痴呆的不同白质损伤模式。在鉴别诊断中,分数各向异性比平均峰度更敏感;从扩散峰度成像得出的分数各向异性可能成为鉴别诊断轻度认知障碍的帕金森病和痴呆的帕金森病的有希望的成像标记。