Cage-like radiotherapy system for noncoplanar radiotherapy

The aim of this study was to design a cage-like radiotherapy system (CRTS) to further promote the clinical application of noncoplanar radiotherapy. The CRTS comprises two stands, two O-rings, several arc girders, an X-ray head, an imaging subsystem, and a treatment couch. The X-ray head rotates with O-rings around the patient’s body and slides along the arc girder. Compared with the C-arm linear accelerator (C-Linac), the clinically available spatial irradiation angle ranges (SIARs) of the CRTS for the head, chest, and abdomen were 33%, 63.6%, and 62.6% larger, respectively. Moreover, according to a preliminary planning comparison based on the dose distribution simulation method, the CRTS achieved much better protection of normal tissue than the C-Linac. Furthermore, the CRTS enabled accurate noncoplanar irradiation without movement of the body being irradiated, allowed automatic control of the movements of different parts without risk of collisions, and provided continuous radiation over an angle that considerably exceeded a full turn. These advantages make CRTS very promising for noncoplanar radiotherapy.