Positron emission tomography in dementia.

Positron emission tomography (PET) studies in dementia suffer from methodological differences. Most PET studies concern resting state metabolism in Alzheimer's disease and its correlations with neuropathology and neuropsychology. Only few clinically based PET studies on sensitivity and specificity of specific findings in specific dementing disorders have been reported. The role of PET in dementia for routine clinical purposes seems limited at present. Future studies should evaluate the potential of PET in preclinical diagnosis and to study treatment effects.