Acute deep-brain stimulation of the internal and external globus pallidus in primary dystonia: functional mapping of the pallidum.
BACKGROUND
Dystonia is a syndrome characterized by prolonged muscle contractions that cause sustained twisting movements and abnormal posturing of body parts. Patients with the severe and generalized forms can benefit from bilateral high-frequency pallidal stimulation.


OBJECTIVE
To investigate the functional map of the globus pallidus (GP) in patients with primary generalized dystonia.


METHODS
Prospective multicenter, double-blind, video-controlled study in patients treated at a university hospital.


METHODS
University secondary care centers.


METHODS
Twenty-two patients with primary generalized dystonia.


METHODS
Acute internal and external pallidal deep-brain stimulation or pallidal deep-brain stimulation.


METHODS
The clinical effects of acute bilateral high-frequency ventral vs acute dorsal pallidal stimulation were assessed with the Movement subscale of the Burke-Fahn-Marsden Dystonia Rating Scale. Intrapallidal localization of the contacts of the quadripolar electrodes was performed using a 3-dimensional atlas-magnetic resonance imaging coregistration method by investigators blinded to the clinical outcome.


RESULTS
Bilateral acute ventral stimulation of the GP significantly improved the Burke-Fahn-Marsden Dystonia Rating Scale score by 42% and resulted in stimulation of contacts located in the internal GP or medullary lamina in 18 of 21 patients. Bilateral acute dorsal pallidal stimulation, primarily localized within the external GP, had variable effects across patients, with half demonstrating slight or no improvement or even aggravation of dystonia compared with baseline.


CONCLUSIONS
Ventral pallidal stimulation, primarily of the internal GP or medullary lamina or both, is the optimal method for the treatment of dystonia. The varying effects across patients of bilateral acute dorsal pallidal stimulation, primarily of the external GP, suggest that unknown factors associated with dystonia could have a role in and contribute to the effects of the electrical stimulation.
Houeto
Jean-Luc
JL
Service de Neurologie, Centre Hospitalier Universitaire la Milétrie, BP 577, 86021 Poitiers CEDEX, France. j.l.houeto@chu-poitiers.fr
Yelnik
Jérôme
J
Bardinet
Eric
E
Vercueil
Laurent
L
Krystkowiak
Pierre
P
Mesnage
Valérie
V
Lagrange
Christelle
C
Dormont
Didier
D
Le Bas
Jean-François
JF
Pruvo
Jean-Pierre
JP
Tezenas du Moncel
Sophie
S
Pollak
Pierre
P
Agid
Yves
Y
Destée
Alain
A
Vidailhet
Marie
M
D000293:Adolescent; D000328:Adult; D046690:Deep Brain Stimulation; D004311:Double-Blind Method; D004421:Dystonia / Q000628:therapy*; D004558:Electric Stimulation; D005260:Female; D005917:Globus Pallidus / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000502:physiology; D011446:Prospective Studies; D016896:Treatment Outcome