Effect of DAVID system on dosimetry of linear accelerator / 医疗卫生装备

Objective To explore the effect of DAVID system on the beam dosimetry of ELEKTA Synergy accelerator. Methods Three-dimensional water phantom system was used to measure the values of percentage depth dose (PDD) in different fields,gun-trarget(G-T)in different fields and depths as well off-axis ratio(OAR)at left-right(L-R)direction when the accelerator was equipped with DAVID system or not. Results DAVID system had no effects on PDD and OAR, while influenced the absorbed dose so that the ray was attenuated by 7%.Conclusion The field parameters have not to be modified for the planning system when using DAVID system,but the dose correction has to be performed according to ray transmission factors.