neurologic disorders
Vascular Cognitive Impairment and Dementia
Diagnosis of Vascular Cognitive Impairment and Dementia
Generally similar to diagnosis of other dementias Neuroimaging Diagnosis of vascular cognitive impairment and dementia is similar to the Diagnosis . A general Cognitive or behavioral (neuropsychiatric) symptoms interfere with the ability to function at work or do usual daily activities. These symptoms represent a decline from previous levels of functioning. These symptoms are not explained by delirium or a major psychiatric disorder. Evaluation of cognitive function involves taking a history from the patient and from someone who knows the patient plus doing a bedside How to Assess Mental Status or, if bedside testing is inconclusive, Differentiation of vascular cognitive impairment and dementia from other dementias is based on clinical judgment. Factors that suggest vascular cognitive impairment and dementia (or Alzheimer disease with cerebrovascular disease) include the following: Imaging evidence of brain infarcts and other vascular brain damage Clinical features characteristic of vascular cognitive impairment and dementia (eg, prominent executive dysfunction, mild or absent memory loss) High Modified Hachinski Ischemic Score (if brain imaging is not available) Confirmation of vascular cognitive impairment and dementia requires a history of stroke or evidence of a vascular cause for dementia detected by neuroimaging. If focal neurologic signs or evidence of cerebrovascular disease is present, a thorough Evaluation should be done. CT and MRI may show Bilateral multiple infarcts in the dominant hemisphere and limbic structures Multiple lacunar strokes Periventricular white-matter lesions extending into the deep white matter In Binswanger dementia, leukoencephalopathy in the cerebrum semiovale adjacent to the cortex, often with multiple lacunae affecting structures deep in the gray matter (eg, basal ganglia, thalamic nuclei) In CADASIL and CARASIL, diffuse white matter hyperintensities with ischemic lesions in subcortical regions, including characteristic involvement of the anterior temporal lobe In cerebral amyloid angiopathy, lobar hemorrhage, multiple cortical microhemorrhage or superficial siderosis ). The Hachinski Ischemic Score is sometimes used to help distinguish vascular cognitive impairment and dementia (mainly multi-infarct dementia) from Alzheimer disease when no brain imaging is available ( Diagnosis reference ). The diagnosis of CADASIL and CARASIL can be confirmed by genetic tests, which identify characteristic mutations of the NOTCH3 gene for CADASIL and HTRA1 gene for CARASIL. Sometimes a skin biopsy can be done instead to confirm the diagnosis of CADASIL. 1.Hachinski VC, Iliff LD, Zilhka E, et al: Cerebral blood flow in dementia, Arch Neurol 32 (9):632–637, 1975. doi: 10.1001/archneur.1975.00490510088009 