[White Matter Lesion and Alzheimer's Disease: The Association between Small Vessel Disease and Neuropsychiatric Symptoms in Alzheimer's Disease].

Cerebral small vessel disease (SVD), including subcortical lacunar infarcts (lacunes) and white matter hyperintensities (WMH), is commonly observed on MRI of elderly individuals with and without dementia. SVD is frequently observed in patients with Alzheimer's disease (AD). However, the association between SVD and clinical symptoms exhibited by patients with AD remains unclear. Our recent studies suggest that cerebral SVD observed on CT/MRI of patients with AD is associated with delusions and delirium as well as depression. Mechanisms underlying these psychiatric symptoms in patients with AD remain unclear.