Neuroimaging of Dementia

Abstract

Any person with progressive cognitive impairment should be studied with brain imaging to rule out a reversible cause, such as a benign brain tumor, a subdural hematoma, or hydrocephalus. Additionally, imaging can help separate the various types of currently not-treatable dementia and facilitate the prognosis of these disorders. Medial temporal atrophy on magnetic resonance imaging, and decreased metabolism in parietotemporal association cortex and retrosplenial region on positron emission tomography are early findings in Alzheimer's disease (AD). Amyloid deposition in AD and Lewy-body dementia help differentiate these disorders from dementias without amyloid deposition, such as frontotemporal dementia and corticobasal degeneration.