DBS surgery has changed the therapeutic approach to PD, allowing the management of motor fluctuations and dyskinesia. This benefit has been proven to be sustained over many years. Recent evidence supports the use of STN DBS even earlier within the course of the disease. Unfortunately, DBS is not a neuroprotective therapy for PD and does not prevent the disease to progress. In addition, STN stimulation is not effective on postural instability, gait impairment and cognitive decline, which represent a main burden for patient and caregivers.
Many efforts have been directed in order to discover other alternative targets, but so far none of these seems to be consistently effective on axial signs. Unfortunately to date, most of these new alternative targets remain experimental. The available data are too scarce to allow defining guidelines for the clinicians. Results from studies assessing the stimulation of the PPN region, although promising, are still controversial. Methodological issues, mainly concerning targeting, patient selection, electrode position as well as stimulation parameters, can account for these discrepancies and should be solved by larger and better designed trials in the near future.
Other possible interesting approaches to address both dopaminergic and non-dopaminergic symptoms might be represented by a multi-target strategy or 'intelligent' stimulation devices.
Expert Rev Neurother. 2013;13(12):1319-1328. © 2013 Expert Reviews Ltd.