Drug treatments
In the case of drug-induced dystonia, it is possible very quickly to find alternative treatments to psychosis or nausea, while treating the residual effect of the previous treatment on the spasms.
In the case of dopa-sensitive dystonia, spasms diminish considerably under the effect of drugs that restore dopamine levels in the brain.
Patients suffering from focal or segmental dystonia are treated with local injections of botulinum toxin into the muscles affected by involuntary contractions.
Botulinum toxin has the effect of locally reducing muscle contraction without affecting nerve transmission. For optimum effectiveness, injections should be repeated regularly (over several months). In some cases, physiotherapy can enhance the beneficial effect of botulinum toxin injections.
In the case of generalised dystonia, treatment is based on anticholinergic drugs. These molecules reduce spasms by blocking the messages sent by the neurons to the muscles. As the side effects of these treatments can be severe for patients, an alternative therapy is to use a mild sedative combined with a muscle relaxant (muscle relaxant).
In certain severe forms of dystonia, transcranial magnetic stimulation or deep brain stimulation (DBS) may be necessary.
The therapeutic principle of these technologies is based on sending electrical or magnetic stimulation to the affected brain regions in order to restore their function. Deep brain stimulation involves implanting an electrode in the patient’s brain to provide deep electrical stimulation to specific regions.
Transcranial magnetic stimulation, which is non-invasive, involves applying a magnetic field to the surface of the skull to modulate the activity of more superficial structures such as the cortex or cerebellum.
In certain very rare cases, surgical removal of the globus pallidus (cerebral region of the basal ganglia) may be indicated.
At the Paris Brain Institute
The search for new therapeutic solutions and new targets for cerebral stimulation is at the heart of the research carried out by Marie Vidailhet and Stéphane Lehéricy’s team, in conjunction with the reference centre at the Hôpital de la Pitié-Salpêtrière AP-HP.
A team coordinated by Professor Emmanuel Flamand-Roze of the Pitié-Salpêtrière Hospital, AP-HP, and a researcher at the Institut du Cerveau, has tested the efficacy of zonisamide, a drug currently used to treat certain forms of epilepsy, in 23 patients with myoclonic dystonia.
For more information: https://institutducerveau-icm.org/en/actualite/an-effective-drug-against-myoclonic-dystonia-rare-disease-of-the-nervous-system/
A study conducted by Zuzana Kozutska, winner of the ICM’s Clinical Research Fellow award, in Marie Vidailhet and Stéphane Lehéricy’s team, has shown the long-term benefit (over 10 years of follow-up) of deep brain stimulation in the internal globus pallidus, a structure of the basal ganglia, in a particular form of dystonia, myoclonus dystonia, with an excellent improvement in motor functions and social adaptation.
Teams at the Institut du Cerveau, in conjunction with the PANAM platform of the Centre de Neuroimagerie de l’Institut du Cerveau (CENIR), are pioneers in the use and development of transcranial magnetic stimulation.