For which patients do you consider stereotactic radiosurgery rather than focused ultrasound for treatment of essential tremor?

Stereotactic radiosurgery (SRS) thalamotomy has a very limited role in my practice. Although SRS can provide meaningful tremor reduction and is an option for patients who are not candidates for DBS or MR-guided focused ultrasound (MRgFUS), I only consider it in highly selected circumstances, primarily when the patient needs an ablative treatment but is not an appropriate candidate for either MRgFUS or an invasive RF procedure.

Situations in which I might consider SRS include:

• Patients in whom an invasive procedure carries substantial risk. SRS may have a niche in exceptionally frail patients or those with significant medical or anesthetic risk who are not candidates for DBS and can not have MRgFUS.
• Reasons people can’t have MRgFUS are:
• Sku...

One might consider stereotactic radiosurgery rather than focused ultrasound when the patient's Skull Density Ratio (SDR) is below 0.30. That said, favorable results can be obtained in patients with an SDR <0.30, although less predictably. The obvious alternative to stereotactic radiosurgery is the tried and true stereotactic radiofrequency thalamotomy.