Stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) are ultra-precise forms of external beam radiotherapy. In certain situations, a stereotactic form of radiation may be recommended by your radiation oncologist or neurosurgeon to be used in addition to regular radiation, on its own or possibly instead of surgery. Sometimes SRS/SRT requires the placement of a frame that attaches to the skull while some systems allow the use of a tight-fitting mask. The benefit of SRS/SRT is that the total radiation dose (which can be a higher dose than standard radiation) is delivered in one to five treatment sessions with very little radiation to the surrounding healthy tissue.