Quality assurance on accuracy of the external laser centre in CT simulator

Objective: Transpherical technique of CT scanner of beekley spot quality assurance (BBQA) and its effect in CT simulator QA. Methods: Vertical column,BB,Jig,Philips PQS-Falcon CT, ACQSIM workstation and the laser system were used. Scanning BB was used in sending image to the AC- QSIM workstation. In this system, after describing the BB, isocenter can be established. Then, the couch with the lasers were moved to the programmed position. Checking was needed. Results: The center of the laser should just be found on the BB. Otherwise the laser system should be regulated again. Conclusions Beekley spot quality assurance, being the very important center' of any QA program, influences the accuracy of quality of the treatment. (authors)