Micro-vascular Diseases of White Matter

ABSTRACT

White matter hyperintensity (WMH) is commonly observed on the brain MRI of elderly subjects. It has been considered as an important biomarker for the micro-vascular damages of white matter of the brain. Aging, hypertension, diabetes mellitus, and hyperhomocysteinemia have been associated with WMH development. WMH is an important risk factor for the vascular dementia (VD), however it also considered as one of risk factors for conversion of mild cognitive impairment to dementia and progression of Alzheimer's disease (AD). WMH has impact on gait, bladder control, and fine motor coordination. It also has negative effects on memory retrieval, mental flexibility, mental processing speed, and executive function by disconnecting nerve fibers that convey signals for normal cognition. Control of vascular risk factors can delay progression of WMH and this may be beneficial for VD as well as AD with ischemic changes, especially in the early state of diseases. In this paper, we will review clinical significance of WMH and three important diseases, subcortical vascular dementia, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, and cerebral amyloid angiopathy that associated with cerebral micro-vascular damages.