Chronic motor cortex stimulation for movement disorders: a promising perspective.

Five patients affected by thalamic hand and international myoclonus have been evaluated and selected for chronic motor cortex stimulation. A quadripolar electrode strip was placed epidurally under local anesthesia through an MR-image-guided single precentral burr hole placed following the morphologic recognition of the central sulcus. Intra-operative stimulation was used to induce muscle contraction at the affected site to confirm the correct placement of the electrode. A one-week trial period preceded the implant of an internal pace-maker under general anesthesia. A remarkable decrease in pain was reported by four patients together with the reduction of dystonia and rigidity in thalamic hand and marked decrease of intentional myoclonus. No complications or undesired side effects of electrode implant and stimulation were observed.