Contribution of multi-modal imaging to our understanding of dystonia pathogenesis.

Dystonia is one of the most common forms of movement disorder, involving repetitive or sustained contractions of antagonistic muscle groups causing pain and abnormal posturing. The motor phenotypes observed in dystonia are varied with single muscle group involvement (focal), multiple adjacent (segmental) and more generalised forms involving multiple body regions. Some dystonia’s are task specific, being induced by undertaking a particular task or movement, whereas with others the involuntary movements and posturing are independent of activity. Dystonia is increasingly considered to be a network-based disorder involving multiple motor pathways in the brain, with the cerebellum, basal ganglia and sensorimotor cortex particularly implicated. Injected botulinum toxin represents the mainstay of treatment for many patients with focal and segmental forms and Deep Brain Stimulation (DBS) is used in the treatment of more severe forms.