title: A quality assurance program in stereotactic radiosurgery using the Gamma Knife unit.
abstract: Because of the large single-fraction dose in stereotactic radiosurgery it is important to guarantee a high geometric and dosimetric accuracy. The paper represent the quality assurance program for the Gamma Knife unit at the University Clinic of Neurosurgery in Graz. The program includes the following procedures: timer control, mechanical radiation isocenter coincidence, trunnion centricity, helmet microswitches test, radiation output and relative helmet factors, dose profile verification, safety interlocks checks and software quality assurance. In summary, the mechanical accuracy and reproducibility of the Gamma Knife unit are < 1 mm. The geometric failure in stereotactic Gamma Knife treatment is limited by the human error in setting the clinical target volume and the spatial accuracy of dose delivery to the patient is limited by the accuracy of modern target localization procedures.
authors.affiliation: Universitätsklinik für Radiologie, Klinische Abteilung für Strahlentherapie, Graz, Austria. georg.stuecklschweiger@kfunigraz.ac.at
authors.forename: G F
authors.initials: GF
authors.lastname: Stuecklschweiger
authors.forename: K
authors.initials: K
authors.lastname: Feichtinger
mesh_terms: D001317:Austria; D006801:Humans; D011785:Quality Assurance, Health Care; D016634:Radiosurgery / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D013997:Time Factors