Inclusion and exclusion criteria for DBS in dystonia

Abstract

When considering a patient with dystonia for deep brain stimulation (DBS) surgery several factors need to be considered. Level B evidence has shown that all motor features and associated pain in primary generalized and segmental dystonia are potentially responsive to globus pallidus internus (GPi) DBS. However, improvements in clinical series of ≥ 90% may reflect methods that need improvement, and larger prospective studies are needed to address these factors. Nevertheless, to date the selection criteria for DBS-specifically in terms of patient features (severity and nature of symptoms, age, time of evolution, or any other demographic or disease aspects)--have not been assessed in a systematic fashion. In general, dystonia patients are not considered for DBS unless medical therapies have been previously and extensively tested. The vast majority of reported patients have had DBS surgery when the disease was provoking important disability, with loss of independence and impaired quality of life. There does not appear to be an upper age limit or a minimum age limit, although there are no published data regarding the outcome of GPi DBS for dystonia in children younger than 7 years of age. There is currently no enough evidence to prove that subjects with primary--generalized dystonia who undergo DBS at an early age and sooner rather than later after disease onset may gain more benefit from DBS than those undergoing DBS after the development of fixed skeletal deformities. There is no enough evidence to refuse or support consideration of DBS in patients with previous ablative procedures.

Long-term neuropsychiatric outcomes after pallidal stimulation in primary and secondary dystonia

“…Therefore, the neuropsychiatric consequences of GPi DBS on patients with dystonia in the short and long term remain unclear, as does the influence of active psychiatric disorders on the selection of appropriate candidates for the procedure. [12][13][14][15][16][17][18][19][20][21][22] We report the long-term impact of bilateral GPi DBS on the neuropsychiatric profiles of a population of patients with primary and secondary dystonia, assessed with the Structured Clinical Interview for the DSM-IV Axis I psychiatric disorders (SCID-I). 23 METHODS Primary research question.…”

Tolerance of early pallidal stimulation in pediatric generalized dystonia

“…The therapeutic benefit of pallidal DBS has been widely established in the dystonic syndrome irrespective of primary, 1,[5][6][7]10,12,14,16,19,20,22,29 secondary, or heredodegenerative dystonia. 15,39,41 Some studies found the DYT1 mutation to be a prognostic factor of a successful outcome of pallidal DBS, [3][4][5]13,37,42 while others did not.…”

History, Applications, and Mechanisms of Deep Brain Stimulation

“…There has been no difference in outcomes based on DYT1 gene status, 31 but shorter disease duration has been reported to lead to better results. 52,53 Intractable cervical dystonia has also shown improvement in several smaller case series. 37 Secondary dystonia is a set of heterogeneous disorders, and their response to stimulation is more vari- able.…”

“…37 Secondary dystonia is a set of heterogeneous disorders, and their response to stimulation is more vari- able. For example, tardive dyskinesias typically respond well, 53,54 whereas dystonias due to encephalitis and birth injury fare worse.…”