Glenrose Rehabilitation Hospital, Edmonton, Alberta, Canada.
Can J Neurol Sci. 2010 Sep;37(5):595-600. doi: 10.1017/s0317167100010751.
In Parkinson's disease (PD) cell loss in the substantia nigra is known to result in motor symptoms; however widespread pathological changes occur and may be associated with non-motor symptoms such as cognitive impairment. Diffusion tensor imaging is a quantitative imaging method sensitive to the micro-structure of white matter tracts.
To measure fractional anisotropy (FA) and mean diffusivity (MD) values in the corpus callosum and cingulum pathways, defined by diffusion tensor tractography, in patients with PD, PD with dementia (PDD) and controls and to determine if these measures correlate with Mini-Mental Status Examination (MMSE) scores in parkinsonian patients.
Patients with PD (17 Males [M], 12 Females [F]), mild PDD (5 M, 1 F) and controls (8 M, 7 F) underwent cognitive testing and MRI scans. The corpus callosum was divided into four regions and the cingulum into two regions bilaterally to define tracts using the program DTIstudio (Johns Hopkins University) using the fiber assignment by continuous tracking algorithm. Volumetric MRI scans were used to measure white and gray matter volumes.
Groups did not differ in age or education. There were no overall FA or MD differences between groups in either the corpus callosum or cingulum pathways. In PD subjects the MMSE score correlated with MD within the corpus callosum. These findings were independent of age, sex and total white matter volume.
The data suggest that the corpus callosum or its cortical connections are associated with cognitive impairment in PD patients.
在帕金森病（PD）中，已知黑质细胞的丢失会导致运动症状；然而，还会发生广泛的病理变化，并且可能与非运动症状（如认知障碍）相关。弥散张量成像（DTI）是一种对白质束微观结构敏感的定量成像方法。
通过弥散张量纤维束追踪技术，测量帕金森病（PD）患者、伴痴呆的帕金森病（PDD）患者和对照组患者的胼胝体和扣带束通路的分数各向异性（FA）和平均弥散度（MD）值，并确定这些指标与帕金森病患者的简易精神状态检查（MMSE）评分是否相关。
17 名男性（M）和 12 名女性（F）PD 患者、5 名男性（M）和 1 名女性（F）轻度 PDD 患者和 8 名男性（M）和 7 名女性（F）对照组患者接受了认知测试和 MRI 扫描。使用程序 DTIstudio（约翰霍普金斯大学）通过纤维连续追踪算法，在胼胝体上分为 4 个区域，在扣带回分为 2 个区域，以定义束。使用容积 MRI 扫描测量白质和灰质体积。
各组在年龄或教育程度上无差异。在胼胝体或扣带束通路中，各组之间的 FA 或 MD 均无总体差异。在 PD 患者中，MMSE 评分与胼胝体中的 MD 相关。这些发现与年龄、性别和总白质体积无关。
数据表明，胼胝体或其皮质连接与 PD 患者的认知障碍有关。
