5fa18665_surgery___Stanford_Health_Care__Features
[Adavantages] Does not require a head frame screwed into the skull for immobilization, avoiding the pain, headache, nausea and risk of infection seen at times with stereotactic frames. Instead, a non-invasive thermoplastic head mask and image guidance allows stereotactic immobilization. [Features] 
Frameless system
Features/Advantages - Cyberknife Radiosurgery | Stanford Health Care
Features