小的卒中病灶即可导致全脑功能损害并加剧白质疏松患者全脑功能下降。我们前期研究采用DTI和MRS发现，皮层下白质单个梗死灶可引起远隔部位与运动相关的的灰、白质早期出现微结构损害和代谢下降，这种继发性非缺血性损害可阻碍神经功能缺损的恢复。但放射冠的小梗死灶是否在早期可引起全脑灰、白质结构与功能继发性改变，进而导致全脑功能下降尚不清楚。本项目以无颅内、外大动脉显著狭窄的伴和不伴脑白质疏松人群的放射冠孤立性小梗死灶患者为研究对象，于卒中发病后1、4、12和24周分别行DTI、结构MR、MRS和fMRI检测，并基于全脑和感兴趣区分析方法观察全脑灰、白质和海马、前额叶的结构、功能和代谢改变模式；同步采用敏感的神经心理学测试法，检测患者相应时间点的执行、记忆和注意功能，并探讨伴和不伴白质疏松患者局灶性脑梗死后认知功能与MRI改变的相关性。本研究结果将为阐明卒中后早期认知损害的机制和进一步防治提供依据。

Little stroke lesions can result in decline of globle function and aggravate decreased cognitive function in patients with white matter hyperintensities. Results of our previous studies using DTI and MRS indicated that early non-ischemic microstructure damage and metbolism decline in both grey and white matter related to motor occurred after cerebral infarction in subcortical white matter, which may hamper functional recovery . However, it is not well known that little infarction lesion in corana radiata can impact structure and function of whole bain and furtherly induce early cognitive impairment.Therefore, corana radiata infarction patients with or without white matter hyperintensities who have no serious stenosis in intra or extracranial arteries will be screened rigorously and examined by means of functional magnetic resonance, diffusion tensor imaging, volumetric magnetic resonance and magnetic resonance spectroscopy at 1w, 4w, 12w and 24w. Present study aim to investigate early, dynamic changes of structure and function models in the whole bain and prefrontal lobe, hippocampus based on analysis methods of global and region of interest. Meanwhile, sensitive neuropsychologic tests will be also synchronously operated to subjects in order to evaluate the executive function, memory and visuospatial attention function following cerebral infarction. furthermore, relationship between results of neuropsychologic tests and changes of MRI will be furthery analyed. defining the relationships will be helpful to clarify early mechanisms of cognitive impairment after stroke and provide basis for stroke prevention and treatment.