[The contribution of nuclear medicine procedures in the diagnosis of dementia of Alzheimer's type. Imaging beta amyloid plaques].

Pathogenesis of dementia of Alzheimer's type (DAT) is unknown. Progressive deposition of beta-amyloid plaques (beta-AlphaPs) is one of the major pathological features of DAT and precedes cognitive decline in these patients. Noninvasive detection of beta-AlphaPs could, therefore, may be a potential diagnostic test for the early detection of DAT patients. A series of derivatives that achieve high binding affinity for beta amyloid fibrils both for PET and SPET studies have been developed for imaging AlphaPs in the living human brain. Lesions at the very early but also at late stages of the disease can also be identified by nuclear medicine techniques.