Positron emission tomography neuroimaging in neurodegenerative diseases: Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis.

Neurodegenerative diseases are a growing problem of ageing societies. Their insidious onset, and the lack of reliable biomarkers, result in significant diagnosis delays. This article summarises the results of studies on the use of positron emission tomography (PET) in the diagnosis of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. It focuses on clinical-pathogenetic aspects of individual diseases, as well as disease-specific patterns relevant in differential diagnosis and in assessing the risk of disease development and prognosis.