Bilateral Electrostimulation of Globus Pallidus in Torsion Dystonia

A.A. Tomskiy, V.A. Shabalov, A.V. Dekopov, E.D. Isagulyan, E.M. Salova

Burdenko Research Institute of Neurosurgery, Moscow, Russia

 

The goal has been studying results, obtained in electrostimulation (DBS) of a medial segment of globus pallidus (GPI) in torsion dystonia.

Material and Methods. Stereotaxic implantation of systems for bilateral stimulation (KINETRA) of GPI was performed in 42 cases. A catamnestic period varied from 3 months up to 6 years. Primary generalized and segmental dystonia, cervical dystionia and secondary dystonia were watched in 24, 10 and 8 cases, respectively. Results were estimated on the basis of the GOS Scale (Global Outcome Scale of the Texas Hospital).

Results. As for primary generalized and segmental dystonia, considerable (14 patients) or moderate (3 patients) reduction of motor disorders with function improvement (4b and 3b according to the GOS Scale) was achieved in 70.8% of cases. Moderate reduction of motor disorders, combined with minimum or no function improvement (2b according to the GOS scale), was watched in 3 cases (12.5%). Only 1 case (4.2%) had minimum motor improvement with unchanged function (1b according to the GOS Scale). The results did not exceed 2b in 3 cases (12.5%), who had undergone thalamotomy earlier.

Good results were achieved in 60% of cases with cervical dystonia; they were estimated as 1b and 2b in 20% of patients. The same indices (1b and 2b) were obtained in cases, who had already undergone bilateral destruction of VL and Cajalís nucleus (20%). Function improvement was present only in 1 case with secondary dystonia (3b); it was minimum or absent in 7 patients (2b or 1b). Pseudobulbar syndrome was watched in a patient with thalamotomy, performed earlier. Transient neurological disorders were eliminated by changing a neurostimulation program.

Conclusion. DBS of GPI is effective in primary dystonia. Its use in cervical dystonia is recommended in case of low efficacy of botulinotherapy. Treatment of secondary dystonia is characterized by poor results. Preceding thalamotomies reduce DBS efficacy and increase a risk of complications.