Main idea: Focused ultrasound subthalamotomy treatment improved neuromotor function of Parkinson’s disease in selected patients with asymmetric signs. But such a treatment also had adverse events, such as speech and gait disturbances, weakness on the treated side, and dyskinesia.
The subthalamic nucleus is the preferred neurosurgical target for deep-brain stimulation to treat cardinal motor features of Parkinson’s disease. Focused ultrasound is an imaging-guided method for creating therapeutic lesions in deep-brain structures, including the subthalamic nucleus. We randomly assigned patients with markedly asymmetric Parkinson’s disease who had motor signs not fully controlled by medication. The primary efficacy outcome was the between-group difference in the change from baseline to 4 months in the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) motor score. The primary safety outcome (procedure-related complications) was assessed 4 months after surgery. Among 40 enrolled patients, 27 were assigned to focused ultrasound subthalamotomy (active treatment) and 13 to the sham procedure (control) The mean MDS-UPDRS III score for the more affected side decreased from 19.9 to 9.9 at 4 months in the active-treatment group. Adverse events included dyskinesia in the off-medication state in 6 patients and in the on-medicated state in six. In 6 patients in the active-treatment groups, some deficits were present at 12 months. Focused ultrasound subthalamotomy in one hemisphere improved motor features of Parkinson’s disease in selected patients with asymmetric signs. Adverse events included speech and gait disturbances, weakness on the treated side, and dyskinesia. (Funded by Insightec and others; ClinicalTrials.gov number, NCT03454425.).