PET Imaging of Dementia

In the medical dictionary, dementia is defined in the following way: “Dementia is a loss of mental ability severe enough to interfere with normal activities of daily living, lasting more than six months, not present since birth, and not associated with a loss or alteration of consciousness”. Dementia is usually caused by neurodegenerative diseases, e.g., Alzheimer’s disease (AD), frontotemporal lobar degeneration (FTLD), dementia with Lewy bodies (DLB) or vascular lesions. However, some psychiatric syndromes, e.g., severe major depression (MD) and severe metabolic abnormalities, e.g., serious hypothyroidism, can mimic dementia. Specific organic disorders, e.g., multiple sclerosis, AIDS, prolonged abuse of alcohol or other drugs, may also cause dementias. In the daily routine of a positron-emission tomography (PET) center, patients with dementia or questionable dementia caused by neurodegenerative disorders have been examined.