[The role of tremorometry in predicting the outcome of ablative surgeries]

Ablative neurosurgical interventions are widely used for the treatment of advanced Parkinson's disease. However, in some cases, the achieved result is temporary and repeat operation is necessary to obtain a permanent effect. By analyzing 30 ablative surgeries using comparative accelerometry, we looked for a biological marker predicting the efficiency. In 27 cases where clinical symptoms were permanently improved, a significant increase in rest tremor frequency was observed in addition to reduction in tremor intensity. In contrast, in those three cases where the clinical effect of the surgery was only temporary, the frequency of tremor remained unchanged despite of the transitory decrease in intensity. We thus hypothesize that postoperative change in frequency of tremor but not the intensity may predict the outcome of ablative treatments.