Dose Evaluation of Treatment Planning using Monte Carlo for Cyberknife

Abstract

The CyberKnife (Accuray, Inc., Sunnyva1e, CA), which consist of a 6 MV energy Iinear aecelerator (LINAC), is an image-guided frameless stereotactic radiosurgery system. Since Cyberknife syslem delivers high doses to a small target and a larget adjacent to a critica1 organ, it is important 10 deliver an optimized dose distribution to an accurately delineated target volume comparεd with that required for conventiona1 treatmenl system. This study implemented the dose evaluation of treatment planning using Monte Carlo method for a Cyberknife stereotactic radiosurgery system. The EGSnrc user code BEAMnrc and the DOSXYZnrc code, which has been demonstrated 10 be the most accurate dose ca1culation method for radiation therapy treatment planning, was used to simulate a 6 MV photon beam emerging from the Cyberknife system and 10 eva1uate the dose ca1culation.