This article gives an excellent description of the process used by Israel’s Insightec to treat the symptoms of Parkinson’s and Essential Tremor patients. The technology is being used in over 50 medical centers around the world and has treated over 2,000 neuro-patients.
https://www.timesofisrael.com/israeli-startup-uses-ultrasound-waves-to-reduce-parkinsons-tremors/