IMPROVEMENT OF SEVERE POSTURAL CEREBELLAR TREMOR IN MULTIPLE-SCLEROSIS BY CHRONIC THALAMIC-STIMULATION

Tremor can be particularly disabling in patients with multiple scleros is (MS) and is mildly improved by drug treatment. The efficiency of st ereotactic thalamotomy has been reported in a small number of patients but was counterbalanced by severe postoperative complications. Stimul ation of the thalamic ventral intermediate nucleus, which is a less ag gressive surgical method, is efficient in essential and in parkinsonia n tremors. We report here the results of thalamic stimulation in 13 pa tients with MS with tremor. All patients were subjected to clinical ex amination, videorecording, and quantification of the functional disabi lity before surgery and 3 months postoperatively. The surgical interve ntion was well tolerated in all cases. A clear improvement of the trem or was observed in 69.2% of the patients. Functional improvement was m ore varied and depended on the severity of tremor and coexistence of o ther neurological symptoms. Of the eight most severely affected patien ts, seven recovered the possibility to easily catch an object and use it. The results indicate that thalamic stimulation may be useful in th e treatment of severe postural cerebellar tremor in MS.