structural neuroimaging in dementia

Dementia is a common and growing problem, affecting 5% of the over 65s and 20% of the over 80s. Dementia is a clinical diagnosis, but often neuroimaging is crucial for proper assessment. Structural imaging by computed tomography (CT) and magnetic resonance (MRI) may help clinicians by identifying nondegenerative and potentially treatable causes of cognitive impairment which, however, account for only 1% of all causes of dementia. In the last years the focus of imaging in patients suspected of having dementia has shifted from an exclusionary to an inclusionary approach. The availability of new treatments for dementia, as well as the importance of subtype-specifi c management, has renewed interest in the use of brain imaging techniques that can assist in the accurate recognition of Alzheimer’s disease (AD), dementia with Lewy bodies (DLB), vascular dementia (VaD) and frontotemporal lobe degeneration (FTLD). In many cases, the specifi c pattern of cortical and subcortical abnormalities on MRI has diagnostic utility. Furthermore new imaging techniques carry the hope of revolutionizing the diagnosis of neurodegenerative disease so as to obtain a complete characterization (i.e. molecular, structural, and metabolic), which could be used to improve diagnosis and to stage each patient and follow disease progression and response to treatment. Although only clinical assessment can lead to a diagnosis of dementia, neuroimaging is clearly an invaluable tool for the clinician in the differential diagnosis