[Pathophysiological mechanisms implicated by high-frequency stimulation in Parkinson's disease: the restoration of high and low frequency oscillatory systems]

[Deep brain stimulation and Parkinson's disease]

Ten years after the therapeutic revolution that emerged from the discovery of l-dopa, some pioneer teams led the rebirth of a new nonablative stereotaxical surgical treatment, which came from the interest of high frequency stimulation. Three targets were retained as the main location of a reversible functional inhibition: Vim, GPI and STN. The unilateral or bilateral stimulation, adjustable and possibly reversible, led to an exceptional medicosurgical collaboration, within expert dedicated places, based on the control of the Parkinson's disease's (PD) triad. The stimulation was initially applied to the most advanced forms of PD, after the medical control period of the motor performance, when the pejorative effects of the evolution settled and/or when side effects of the treatment appeared. Subsequently, the research of selection criterions and the strict control of the stereotaxical procedure during the per- and postoperatory period, with the collaboration of the patient and his family, progressively brought different teams to an earlier indication of this new treatment option, up to now reserved for fully medicosurgical concerted cases. Apparition of cognitive and postural decline as well as the known resistance stage to l-dopa tend to become a real contra-indication. Despite the initial relative weakness of controlled studies with limited number of patients, the multiplication of follow-up studies among high quality multicentric cohorts enabled the validation of practices respecting the differences related to the initial background of each different team. In Europe first, the prevalence of the subthalamic target is now to be generally admitted. A new objective is now imposing itself: trying to maintain the patient's quality of life, beyond the only motor benefit. The social adaptation of a young patient is now also taken into account. If this exemplary clinical research approach, efficient for a few highly selected patients, has not transformed the long-term prognostic of the PD, it will continue to improve the comprehension of this degenerative pathology and its extension. It still remains hopeful for the future in the actual constant technological progress, and that probably beyond the only PD.