What can imaging tell us about cognitive impairment and dementia?

Core Tip

Core tip: Dementia is a clinical diagnosis that cannot be made on imaging. Structural and molecular imaging techniques are useful to identify the likely underlying neuropathology. Neuroimaging techniques, such as computed tomography (CT) and blood flow single photon emission computed tomography (SPECT) are routinely used in clinical practice in all newly diagnosed dementia patients. Structural imaging with CT or magnetic resonance imaging is useful in suspected frontotemporal dementia. Amyloid positron emission tomography imaging has recently been introduced into clinical practice and is likely to be most useful in early onset Alzheimer’s disease. Dopamine transporter imaging with iodine-123-b-carbo-methoxy-3-b-(4-iodophenyltropane) fluropropyl SPECT has been firmly established in clinical practice to support a diagnosis of Lewy body disease. This article is a review of the imaging techniques not only currently in clinical use but also the emerging imaging techniques in research.