The First Stage Study Of G3 Cyberknife Treatment Feature

Radiosurgery is using stereotatic irradiation technology that delivers a high dose per faction with narrow cross-fired ionizing radiation to destroy the target biological irreversibly, and to spare surrounding normal tissue. A large amount of clinical experience attests to the efficacy of radiosurgery, especially in small benign and border clearly malignant tumor and functional pains within the brain.The requirements for positional accuracy of dose delivery and quality assurance are even more stringent in radiosurgery than in standard radiotherapy, mainly because stereotacitic irradiation is commonly applied to small lesion in proximity to vital radiosensitive structure. Any error could cause serious result irremediably.In general, radiosurgery involves using a rigid precise stereotactic frame which defines a fixed coordinate system for an accurate localization and irradiation of the planning target volume. Either traditional invasive or non-invasive stereotactic frame has its own shortcoming in fractional stereotatic radiosurgery respectively.In nineties, with the development of image technology, computer science and electron technology, more and more new technology and facility are applied in radiotherapy. The first Cyberknife which is image-guided frameless robotic stereotatic radiosurgery system is used in clinic in 1994. Cyberknife could monitor the position change of patient and track target in real-time with x-ray image system and synchrony respiratory tracking system, and could adjust the treatment couch or correct the direction of radiation beam to compensate the target movement automatically. So Cyberknife expands the potential of precision radiosurgery to every part of the body.First the paper reviews the history of radiosurgery, briefly highlights the facility of radiosurgery and introduces the structure of Cyberknife, working principle and treatment feature, second study the accuracy of target localization of Cyberknife through tracking and compensation, analyzes the efforts, which affect accuracy through the CT slice thickness, the parameter of tracking and respiration model, third do some primary work in study accuracy of cyberknife in dosimetry, then discuss the feasibility of approach at cyberknife center of Miami. Finally discusses the margin should be given or not, and the range of margin of target and organ at risk, if it is necessary or not, as well as summaries the attentions during the treatment, establishes quality control to improve the curative effect, ensure the curative safety of radiosurgery.