ABSTRACT
Patient-specic quality control measures are essential for both stereotactic cranial radiosurgery and radiotherapy because of the risks associated with the procedures. For the purpose of this discussion, stereotactic radiosurgery (SRS) will mean a singlefraction, high-dose, highly focused radiotherapy treatment and stereotactic radiotherapy (SRT) will mean hyperfractionated, high-dose, highly focused radiotherapy treatment. Both cranial SRS and SRT are treatments that entail risk of severe consequences to the patient should a deviation from the intended treatment occur because of the proximity of eloquent areas of the brain or critical intracranial structures such as the optic chiasm, optic nerves, or brain stem to the therapeutic high-dose region. Quality control measures must be in place for patient immobilization, imaging, treatment planning, and treatment. General quality assurance references may be found in the published literature: quality assurance for linac-based stereotactic radiosurgery (Drzymala 1991), AAPM Task Group Report 54, stereotactic radiosurgery (Schell and Bova 1995), and quality assurance programs on stereotactic radiosurgery (Hartmann and Lutz 1995). An earlier report of quality assurance methods for a linacbased SRS program with some patient-specic tests is given by Tsai et al. (1991). is chapter describes our institution’s quality control measures for specific patients with intracranial lesions. Extracranial targets require some dierent quality control measures that are not described within this chapter. A conventional linear accelerator for SRS and SRT is used at our institution; thus, we will not be describing quality control measures appropriate for other devices such as GammaKnife, CyberKnife, or
Tomotherapy, although some of the concepts discussed are relevant across all platforms.
