SUMMARY

The Leksell gamma knife ICON is a stereotactic radiosurgery system that is used to non-invasively treat brain conditions. The newer treatment option for the gamma knife utilizes an on-board imaging technique for patient positioning during treatment setup and a motion tracking system to monitor the patient's movement during treatment. In lieu of a patient, a stereotactic quality assurance phantom and a moving platform device was used to vary the position of target GAFChromic film during radiation deliveries, as planned on the Icon system. This project was used to verify the integrated imaging system by treating a shifted target to observe the system's ability to accurately correct patient shifts during setup, as well as to evaluate the motion tracking system by treating a moving target to observe the tolerance at which there would be a clinical detriment to the quality of a simple treatment plan due to patient motion.