[Bilateral deep brain stimulation of subthalamic nucleus STN in the surgical treatment of Parkinson's disease].

Dopamine deficiency in the nigrostriatal system leads to a series of changes in the basal ganglia, resulting in an increased neuronal activity of the subthalamic nucleus (STN). Reduction of the STN glutaminergic excitatory effect on the main output structures of the basal ganglia (globus pallidum pars interna GPi and substantia nigra pars reticulata SNr) is accompanied by a marked alleviation of parkinsonian motor sings in the MPTP monkey model of parkinsonism. Also a high-frequency stimulation of STN in the MPTP monkey model of parkinsonism produced the same clinical effect as did lesioning. Due to these observations bilateral deep subthalamic stimulation was introduced in the treatment of PD patients with severe akinetic-rigid form of this disease. Four patients with akinetic-rigid PD form of PD were included in the study. The electrodes for deep brain stimulation were implanted in two separate surgical interventions in every case. The second implantation was performed not earlier than at least 3 months after the first procedure. Evaluations using the UPDRS were conducted before surgery in "on" and "off" conditions and at 3, 6 and 12 months after the bilateral implantation. Bilateral DBS STN seems to be the best stereotactic target in controlling motor symptoms in the "off" condition in the treatment of PD patients with severe symptoms. The technique enables a dramatic reduction in the daily dose of L-dopa.