Improvement of upper limb ataxia and intention tremor allowing cessation of thalamic electrostimulation after four years.

A 34-year-old female patient suffering from multiple sclerosis was treated with thalamic electrostimulation for right dominant brachial ataxia and intention tremor. At the end of the fourth year, the energy of the battery of the impulse generator was depleted. However, the patient was able to use her hands without major impairment with the stimulator OFF; due to a stable reduction of the degree of ataxia and intention tremor. The opposite thalamus received an electrode that was never activated because of a permanent thalamotomy effect. Thus, it can be concluded that restoration of function by means of deep brain stimulation might have been beneficial towards achieving a reorganization and stabilization of subcortico-cortical and cerebellar circuitry, supporting the process of self-repair in this patient with a less aggressive course of multiple sclerosis. However, scientific proof has yet to be found. This exceptional observation emphasizes the need for longterm studies.