Diffusion tensor imaging study of subcortical gray matter in CADASIL
Diffusion tensor imaging study of subcortical gray matter in CADASIL
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DOI：
10.1161/hs0901.094255
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发表时间：
2001-09-01
期刊：
影响因子：
8.3
通讯作者：
Chabriat, H
中科院分区：
文献类型：
--
作者：
Molko, N;Pappata, S;Chabriat, H
背景和目的：大脑常染色体显性动脉病变伴皮层下病变。脑白质病变（CADASIL），水扩散改变提示微结构组织改变，最近报道在t2加权图像上看到异常和正常的白质。在皮层下灰质中，反复观察到典型的腔隙性梗死。在壳核或丘脑的这些病变外是否也存在微结构组织改变尚不清楚。方法：我们采用弥散张量成像（一种对大脑微结构高度敏感的MRI方法）对20例CADASIL患者和12例对照组进行研究。在典型腔隙性梗死外的壳核和丘脑内，通过T1和t2加权图像测量扩散张量[Tr(D)]和扩散指数（体积比）的各向异性。结果：患者壳核和丘脑的Tr(D)显著升高，各向异性显著降低。丘脑中Tr(D)的左右指数与中央白质中相应的指数有很强的相关性，而壳核中没有。semiovale。此外，丘脑弥散增加与Tr(D)和白质内小深部梗死负荷呈正相关，与迷你精神状态检查评分负相关。结论：我们的研究结果表明，在CADASIL典型腔隙性梗死外，壳核和丘脑存在微结构组织改变。在丘脑中，这些微观结构的变化似乎是恒定的，甚至在无症状的受试者中也能观察到。其中一些丘脑变化似乎是由缺血性白质损伤继发的丘脑皮质通路退化引起的。这种退行性现象在CADASIL病理生理中的重要性有待进一步研究。
Background and Purpose-In cerebral autosomal dominant arteriopathy with subcortical. infarcts and leukoencephalopathy (CADASIL), water diffusion changes suggestive of microstructural tissue alterations have been recently reported in abnormal- and normal-appearing white matter as seen on T2-weighted images. In the subcortical gray matter, typical lacunar infarcts are repeatedly observed. Whether microstructural tissue changes are also present outside these lesions within the putamen or thalamus remains unknown.Methods-We used diffusion tensor imaging, an MRI method highly sensitive to cerebral microstructure, in 20 CADASIL patients and 12 controls. Both the trace of the diffusion tensor [Tr(D)] and an anisotropic diffusion index (volume ratio) of diffusion were measured within the putamen and thalamus outside typical lacunar infarcts as detected on both T1- and T2-weighted images.Results-A significant increase in Tr(D) and a decrease in anisotropy were observed in the putamen and thalamus in patients. The right/left indices of Tr(D) in the thalamus, but not in the putamen, were strongly correlated with the corresponding indices calculated in the white matter of the centrum. semiovale. In addition, the diffusion increase in the thalamus was positively correlated with Tr(D) and with the load of small deep infarcts within the white matter and negatively correlated with the Mini-Mental State Examination score.Conclusions-Our results suggest that microstructural tissue alterations are present in the putamen and thalamus, outside the typical lacunar infarcts in CADASIL. In the thalamus, these microstructural changes appear constant and are even observed in asymptomatic subjects. Some of these thalamic changes appear to result from degeneration of thalamocortical pathways secondary to ischemic white matter damage. The importance of this degenerative phenomenon in the pathophysiology of CADASIL requires further investigation.