Radiosurgery is a safe and valuable treatment option for medically refractory essential tremor, especially for the elderly or those with high surgical risk for deep brain stimulation (DBS) or radiofrequency thalamotomy, a recent study found. During a 19-year period (1996–2015), researchers evaluated 73 patients who underwent gamma knife thalamotomy for intractable essential tremor. A median central dose of 140 Gy (range, 130–150) was delivered to the nucleus ventralis intermedius through a single 4-mm isocenter. Researchers used the Fahn-Tolosa-Marin clinical tremor rating scale to score tremor, handwriting, drawing, and ability to drink fluids. The median time to last follow-up was 28 months. They found:

• After gamma knife thalamotomy, 93.2% improved in tremor.
• 44 patients (60.3%) experienced tremor arrest or barely perceptible tremor.
• 18 patients (24.7%) noted tremor arrest and complete restoration of motor function.
• Tremor improvement was sustained at last follow-up in 96% of patients who experienced tremor relief.
• Mean tremor score improved from 3.19 before to 1.27 after gamma knife thalamotomy.