[Poster] Comparison between PTW 2D-array Octavius and EPIbeam Measurements of a Complex Head&Neck VMAT Plan
- May 5, 2017
- Category: Patient QA, Scientific Publications, What's New
M. Del Re , Grand Hôpital de Charleroi, Gilly, Belgium
Presented at ESTRO 2017
Introduction: Quality control of VMAT plan is a time consuming task for all medical physics team. The PTW Octavius matrix is widely used for the validation of VMAT plans. The main disadvantage of this system is that the measurement is done only in a fixed plan that is not always representative of the delivered dose. The time required for the set-up is also quite significant.
The goal of this work is to use the benefits of the integrated panel (iViewGT -Elekta Infinity platform) to measure the dose of each arc thanks to the EPIbeam software solution.
Conclusion: EPIbeam offers an alternative solution for patient delivery QC using the iViewGT panel. The advantages are in the set-up time, the spatial resolution of the detector and the perpendicularity of the panel with the beam fluence. Although the detector is always in front of the beam and is not sensitive to gantry error position, it should be noted that the influence of the gantry rotation is taken into account by a specific EPID-arm sag-effect correction applied on the measurement that may returns possible deviations in comparison to ideal operating conditions.