Neuroimaging of movement disorders

This chapter is a review of neuroimaging techniques for detecting and analyzing movement disorders. It is not intended to be an exhaustive review. The intent is rather to emphasize not merely how imaging plays a role in diagnosis, but how it has changed the way we look at movement disorders, with emphasis on its ability to illuminate the causes, from networks to genetics. Recent developments in PET, MRI, and ultrasound are described as they are applied to Parkinson disease, progressive supranuclear palsy, Huntington disease, essential blepharospasm, and torsion dystonia. This chapter will show how imaging has confirmed an old conjecture as to the etiology of dystonia. Finally, this chapter will discuss how MRI can replace brain biopsy and spinal fluid assays as a way of diagnosing Creutzfeldt-Jakob disease.