Optimally, the surgical protocol includes stereotaxic ventriculography to identify targets followed by electrical activity recordings of the structures crossed by the electrode. Finally, a minute study of the stimulation effects is performed under sterotaxic control while the patient is awake. Indications for thalamic stimulation in Parkinson's disease have given way to subthalamic stimulation which improves tremor, bradykinesia and rigidity simultaneously. This result confirms the implication of the subthalamic nucleus in the pathogenesis of Parkinson syndromes. The palladium may be stimulated in Parkinson's patients with major iatrogenic involuntary movements.
Thalamic stimulation is indicated for essential tremor.
The efficacy of chronic stimulation is currently under evaluation in other indications. Strength training can improve steadiness in persons with essential tremor. We evaluated the effect of a strength-training program on the ability of persons with essential tremor to exert steady forces with the index finger. Subjects attempted to generate steady contractions during both postural and constant-force tasks. Steadiness was quantified by the root mean square amplitude of acceleration during postural tasks and the standard deviation and coefficient of variation of force during the constant-force tasks.