Lesion-making surgery versus brain stimulation for treatment of Parkinson's disease

With the resurgence of interest in neurosurgical intervention for the treatment of drug-resistant Parkinson's disease, posteroventral pallidotomy (internal globus pallidus) has become a procedure widely applied by neurosurgeons. In chronic deep brain stimulation, the stimulation target is the same area as the above lesion-making point: the ventralis intermedius thalamic nucleus, subthalamic nucleus, and internal globus pallidus, since deep brain stimulation does not induce brain damage, and it is possible to control the stimulation (frequency and strength). There is also no recurrence. This procedure has the reversibility, selectivity, and adjustability that is ideal for functional neurosurgery. Such chronic stimulation therapy has thus now become an alternative to lesion-making stereotactic surgery. However, stimulation therapy directed at a particular target has more specific effects on particular symptoms of Parkinson's disease, so that an effective stimulation target needs to be selected depending on the nature of the syndrome to be improved. This article presents a review of the most recent reports on how to perform safer and more effective pallidotomy, and of recent basic and clinical reports concerning pallidal stimulation. Some answers to the question of whether or not stimulation therapy is an alternative to lesion-making surgery at the internal globus pallidus to improve parkinsonian syndrome and levodopa-induced dyskinesias are discussed.