# What is the difference between Gamma Knife and CyberKnife?

Source: https://oncologyistanbul.com/answers/gamma-knife-vs-cyberknife
Last updated: 2026-07-23

Both deliver stereotactic radiation — many precise beams that converge on a target without an incision — but they are different machines from different makers. Gamma Knife (Elekta) uses fixed cobalt radiation sources with a head frame and is used almost entirely for the brain and head. CyberKnife (Accuray) mounts its beam on a robotic arm with continuous image guidance, so besides the brain it can treat body sites — lung, spine, prostate, liver, pancreas — as stereotactic body radiation therapy (SBRT), which the National Cancer Institute defines as precisely targeted high-dose radiation given in a few sessions. A given center may operate one, the other, or a linear-accelerator-based system that does the same job, so the specific platform and its availability are hospital-specific and must be confirmed directly. Which approach — if any — fits a case is a radiation oncologist's decision based on the tumor's site and size.

## Verify at
- [NCI Dictionary — stereotactic radiosurgery](https://www.cancer.gov/publications/dictionaries/cancer-terms/def/stereotactic-radiosurgery) — National Cancer Institute (NCI) (checked 2026-07-12)
- [NCI Dictionary — stereotactic body radiation therapy](https://www.cancer.gov/publications/dictionaries/cancer-terms/def/stereotactic-body-radiation-therapy) — National Cancer Institute (NCI) (checked 2026-07-12)

Related: [CyberKnife in Turkey](https://oncologyistanbul.com/cyberknife-turkey)