Deep brain stimulation for dystonia.

Dystonia is a movement disorder characterized by involuntary muscular contractions that generate twisting and repetitive movements and/or abnormal postures. It can affect a few muscle groups (focal dystonia) or spread to most muscles in the body (generalized dystonia). While botulinum toxin injections can be successfully used to treat focal dystonias, medical options for generalized dystonia are very limited. Surgical therapies--and in particular deep brain stimulation (DBS)--are becoming the standard of care for medically intractable, disabling dystonias. Advantages of DBS include reversibility, adjustability and continued access to the therapeutic target. Initial reports describing the use of DBS in generalized dystonia have been very encouraging and experience in the use of DBS to treat various forms of dystonia is continuously growing. This article reviews the issues related to DBS treatment of dystonia, including proper patient selection, surgical approaches to target choice and device implant, a description of the stimulating device and its programming principles, clinical results - with a focus on different outcomes for primary versus secondary and generalized versus cervical dystonia - and complications.