What is Gamma Knife Radiosurgery?
This technique was developed in the 1960’s and allows for the focusing of high and therapeutic doses of radiation with great accuracy thereby limiting damage to surrounding structures. The effect of ionizing radiation to control pain from trigeminal neuralgia was first noted in the early 20th century but due to limitations in technique could not be administered without causing injury to normal tissues. This initial experience, likely, informed the developer of the Gamma Knife, Dr. Lars Leksell in his consideration for using this device for facial pain. Together with the advances in MR imaging to clarify the location and anatomy of the trigeminal nerve, radiosurgery allows for treatment of trigeminal neuralgia by damaging the nerve without the risks associated with percutaneous rhizotomy (Figure 1). Although the treatment is greatly effective and noninvasive there are delayed risks associated with radiation as well as the possibility for recurrent pain.
Figure 1
Gamma knife treatment plan demonstrating targeting of trigeminal nerve.