Treatment of dystonic syndromes by chronic electrical stimulation of the internal globus pallidus.
OBJECTIVE
Dystonia is a medically intractable condition causing twisting or myoclonic movements and abnormal postures. There is an important heterogeneity among etiologies of dystonia. The electrical stimulation of the globus pallidus has been used successfully in primary generalized dystonia. The aim of this study was to examine the long-term efficacy and safety of deep brain stimulation (DBS) in the treatment of primary and secondary generalized dystonia in children and adults.


METHODS
Fifty-three patients were included. Electrodes were bilaterally implanted under stereotactic guidance and connected to neurostimulators, subcutaneously inserted. Efficacy was evaluated by comparing scores on the clinical and functional Burke-Marsden-Fahn dystonia rating scales (BMFDRS) before and after implantation. Patients were divided into 3 groups: group 1 comprised 15 patients with DYT1 dystonia; group 2, 17 patients with dystonia of unknown etiology and group 3, 21 patients with secondary dystonia. The mean follow-up was 26.6+/-12.3 months for primary dystonia and 23.1+/-11.8 for secondary dystonia.


RESULTS
After 1 year, the improvement of the clinical score is 71% in group 1, 74% in group 2 and 31% in group 3. The functional score was improved by 63% in group 1, 49% in group 2 and 7% in group 3. We did not find any significant difference between children and adults. In secondary dystonia, efficacy of the stimulation is more limited. The efficacy of the stimulation improved with time for the 3 groups. COMCLUSION: Electrical stimulation of the internal globus pallidus proved to be an effective treatment for generalized dystonia and should be considered as first-line therapy.
Cif
L
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Research Group on Movement Disorders in Children, Department of Pediatric Neurosurgery, School of Medicine University of Montpellier, Montpellier, France.
El Fertit
H
H
Vayssiere
N
N
Hemm
S
S
Hardouin
E
E
Gannau
A
A
Tuffery
S
S
Coubes
P
P
D000328:Adult; D002648:Child; D004421:Dystonia / Q000503:physiopathology* / Q000628:therapy*; D004599:Electric Stimulation Therapy; D005260:Female; D005917:Globus Pallidus / Q000503:physiopathology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012720:Severity of Illness Index; D016896:Treatment Outcome