Subthalamic nucleus stimulation for Parkinson disease: benefits observed in levodopa-intolerant patients

Abstract
Object. A blinded evaluation of the effects of subthalamic nucleus (STN) stimulation was performed in levodopaintolerant patients with Parkinson disease (PD). These patients (Group I, seven patients) were moderately or severely disabled (Hoehn and Yahr Stages III–V during the off period), but were receiving only a small dose of medication (levodopa-equivalent dose [LED] 0–400 mg/day) because they suffered unbearable side effects. The results were analyzed in comparison with those obtained in patients with advanced PD (Group II, seven patients) who were severely disabled (Hoehn and Yahr Stages IV and V during the off period), but were treated with a large dose of medication (500–990 mg/day). Methods. The patients were evaluated twice at 6 to 8 months after surgery. To determine the actual benefits afforded by STN stimulation to their overall daily activities, the patients were maintained on their medication regimen with optimal doses and schedules. Stimulation was turned off overnight for at least 12 hours...