Neurológia pre prax 5/2013

Deep brain stimulation in dystonia

Dystonia is a heterogeneous group of syndromes manifested by cramp-like involuntary movements or postures of one or more body parts. Some cases are refractory to drug therapy. This makes us consider bilateral deep brain stimulation of the internal pallidus (DBS GPi) which promises significant improvement mainly in disabling generalized and segmental daystonic syndromes. Patients with cervical dystonia with secondary resistance to botulinum toxin may benefit from this treatment as well. Despite the absence of straightforward indication or exclusion criteria there are certain prognostic markers suggesting the future individual clinical effect of DBS. The best results can be obtained in younger patients with primary, genetically determined syndromes, especially with the mobile type of dystonia. Significant improvement can also be expected in sporadic dystonic syndromes beginning in adulthood. Since the effects on secondary dystonias are rather variable, DBS GPi cannot be recommended as a general approach. The following text carries basic information on making a decision with an indication process for DBS in pharmacoresistant dystonias.

Keywords: focal, segmental and generalized dystonia, primary and secondary dystonia, deep brain stimulation, globus pallidus interna, prognostic markers.