Deep Brain Stimulation Treating Dystonia: A Systematic Review of Targets, Body Distributions and Etiology Classifications

Abstract

Background: Deep brain stimulation (DBS) is a typical intervention treating drug-refractory dystonia. Currently, the selection of the better target, the GPi or STN, is debatable. The outcomes of DBS treating dystonia classified by body distribution and etiology is also a popular question.Objective: To comprehensively compare the efficacy, quality of life, mood, and adverse effects (AEs) of GPi-DBS vs. STN-DBS in dystonia as well as in specific types of dystonia classified by body distribution and etiology.Methods: PubMed, Embase, the Cochrane Library, and Google Scholar were searched to identify studies of GPi-DBS and STN-DBS in populations with dystonia. The efficacy, quality of life, mood, and adverse effects were quantitatively compared. Meta-regression analyses were also performed. This analysis has been registered in PROSPERO under the number CRD42020146145.Results: Thirty five studies were included in the main analysis, in which 319 patients underwent GPI-DBS and 113 patients underwent STN-DBS. The average follow-up duration was 12.48 months (range, 3–49 months). The GPI and STN groups were equivalent in terms of efficacy, quality of life, mood, and occurrence of AEs. The focal group demonstrated significantly better disability symptom improvement (P = 0.012) than the segmental and generalized groups but showed less SF-36 enhancement than the segmental group (P < 0.001). The primary groups exhibited significantly better movement and disability symptom improvements than the secondary non-hereditary group (P < 0.005), which demonstrated only disability symptom improvement compared with the secondary hereditary group (P < 0.005). The primary hereditary and idiopathic groups had a significantly lower frequency of AEs than the secondary non-hereditary group (P < 0.005). The correlation between disability symptom improvement and movement symptom improvement was also significant (P < 0.05).Conclusion: GPi-DBS and STN-DBS were both safe and resulted in excellent improvement in efficacy and quality of life in patients with dystonia. Compared with patients with segmental dystonia, patients with focal dystonia demonstrated better improvement in dystonia symptoms but less enhancement of quality of life. Those with primary dystonia had a better response to DBS in terms of efficacy than those with secondary dystonia. Patients who exhibit a significant improvement in movement symptoms might also exhibit excellent improvement in disability symptoms.

Dystonia‐Deafness Syndrome Response to Subthalamic Nucleus Stimulation

“…DBS has been widely used for treating dystonia, and therapeutic targets of the global pallidus internus (GPi) and the STN seem to have similar efficacy 6 . Kwong et al 3 concluded that GPi‐DBS responses varied among different monogenic forms of dystonia, and it did benefit a majority of patients.…”

“…DBS has been widely used for treating dystonia, and therapeutic targets of the global pallidus internus (GPi) and the STN seem to have similar efficacy. 6 Kwong et al 3 concluded that GPi-DBS Video 1. Segments 1, 2, and 3: patient with dystonia-deafness syndrome attributed to a β-actin (ACTB) gene mutation presenting with dystonic gait, cervical dystonia, and scoliosis 5 days before and 7 and 12 months after deep brain stimulation of the bilateral subthalamic nucleus.…”

Bilateral pallidotomy for acquired or heredodegenerative generalized dystonia in children

“…DBS is the preferred treatment modality for patients with isolated dystonia without CNS degeneration or insult is because it is reversible. [22][23][24][25][26][27] However, the advantages of DBS in patients with acquired/heredodegenerative dystonia are not definite. 26,28,29 A recent multicenter, single-arm, randomized, double-blind crossover trial on the effect of DBS in pediatric dystonia patients with dyskinetic cerebral palsy concluded that the evidence is insufficient to recommend DBS as routine treatment for these patients.…”

“…[22][23][24][25][26][27] However, the advantages of DBS in patients with acquired/heredodegenerative dystonia are not definite. 26,28,29 A recent multicenter, single-arm, randomized, double-blind crossover trial on the effect of DBS in pediatric dystonia patients with dyskinetic cerebral palsy concluded that the evidence is insufficient to recommend DBS as routine treatment for these patients. 28 A recent Cochrane review of the role of DBS in dystonia also concluded that the evidence in the available literature is insufficient to draw any conclusions about the advantages of DBS in children and adolescents with dystonia and secondary dystonia.…”

Direct cerebello-striatal loop in dystonia as a possible new target for deep brain stimulation: A revised view of subcortical pathways involved

“…It is also known that STN-DBS is equally effective in treating idiopathic and hereditary dystonias compared to GPi-DBS ( 45 – 47 ), although the stimulation parameters could differ from those in Parkinson's disease ( 48 ). The rationale for this target is not clearly explained, asin dystonia direct pathway predominance must be met with increasing indirect pathway including STN.…”