Central Nervous System Imaging in Movement Disorders

Movement disorders are a group of neurological diseases (recognizing neurodegenerative and non-neurodegenerative etiologies) whose primary symptomatology is related to the lack of movement or, conversely, to an excessive and/or involuntary movement. Among them, neurodegenerative parkinsonian syndromes include Parkinson's Disease, Dementia with Lewy Bodies, and Atypical Parkinsonisms. The differential diagnosis of the neurodegenerative parkinsonian syndromes includes clinical entities such as essential tremor (ET), drug-induced parkinsonism, vascular parkinsonism, and psychogenic parkinsonism. In the last years, the differential diagnosis between these different etiologies has been increasingly guided by molecular imaging. The present chapter deals with the use of Positron Emission Tomography (PET) biomarkers in patients with movement disorders. In particular, as PET's clinical role in this field is most prevalent in patients with parkinsonian syndromes, a more extended discussion is provided about the use of PET in parkinsonism. As a result, dopaminergic imaging is more extensively discussed. Further topics addressed include the use of 18F-Fluorodeoxyglucose (FDG) PET in patients with movement disorders and patients with movement disorders presenting with mild cognitive impairment and dementia. Other tracers such as tracers for Tau and Amyloid PET imaging and tracers for neuroinflammation imaging are more briefly mentioned. Preliminary data and challenges related to the development of tracers for alpha-synuclein are also reported.