EP-1533: Sensitivity of ArcCheck system to setup error using Perfect Pitch 6D couch
Vaibav Mhatre, Parimal T. Patwe, Prasad Dandekar · Radiotherapy and Oncology · 2016
Purpose or Objective: Machine Performance Check (MPC) is an application to verify geometry and beam performances of Truebeam STx , through automated checks .In this study,MPC tests were analysed using all photon beam energies of our Truebeam STx, comparing whenever possible with external independent checks. Material and Methods:The Machine Performance Check (MPC) is a new Truebeam STx major mode, designed to evaluate the machines geometric performance.Data acquisition comprises a series of 39 images acquired with IsoCal Phantom & with particular MLC pattern settings.MPC performs geometric and dosimetric checks.The geometric checks intend to test the treatment isocenter size and its coincidence with imaging devices, the positioning accuracy of the imaging systems, collimator, gantry, jaws, MLC leaves & the couch position.The dosimetric checks refer to a reference MV image and give the beam output, uniformity and center change relative to the reference.MPC data were acquired during one month on different consecutive days.For most of the MPC checks, an independent control has been performed at the same time of the acquisition of the MPC to evaluate the agreement of the two methods.For the independent checks, phantoms and detectors available & used routinely in the department were used.The Daily QA3 was used to check the beam constancy.The first acquisition, acquired at the same time as the MPC baseline, was used as reference.Also weekly output was performed as per TRS 398 protocol on water phantom using FC 65 chamber to compared with the MPC and Daily QA3 output.