Deep brain stimulation electrode used for radiofrequency lesion of the globus pallidus internus in dystonia

Background: There have recently been increasing case reports in the literature of deep brain stimulation (DBS) electrodes used for lesioning with satisfactory clinical success in the treatment of Parkinson disease and tremor. Methods: After preliminary experiments of radiofrequency (RF) lesioning with a quadripolar DBS lead, a paediatric case of generalized primary dystonia was treated by RF lesioning of the globus pallidus internus (Gpi) with an electrode previously used for chronic stimulation. In order to study electrode damage related to the RF procedure, an electron microscopy study (SEM) at different magnifications (×40 and ×300) was performed. Results: Nine months after the unilateral pallidotomy, the patient had a good and stable control of dystonia. The MR study showed a T₁-weighted hyperintensity signal corresponding to the electrode contacts used for lesions. The SEM scans of the DBS electrode used for RF lesioning did not show alterations of the ultrastructure. Conclusions: The RF lesioning technique by a DBS electrode allows small and staged lesions and could also be performed in a bilateral target. The versatility, efficacy, safety and low cost of the device make this approach suitable in selected cases.