RESUMO
PURPOSE: The Daily QATM3 phantom from Sun Nuclear Corporation has been a popular daily quality assurance (QA) tool for many institutions. PTW has recently introduced the QUICKCHECKwebline phantom as an alternative. The goal of this study was to compare these two commercially available devices for daily quality assurance measurements of a linear accelerator and assess the overall performance of the new phantom. METHODS: Two daily QA phantoms (PTW QUICKCHECKwebline and Sun Nuclear Corporation Daily QATM3) were measured over a 4-month period using a 20x20cm² field size and delivering 150 MU. Photon energies of 6 and 18 MV were measured on a daily basis, and electron energies of 6, 9, 12, 15, and 18 MeV were measured weekly on a 23EX Varian Linear Accelerator. Consistency of the dose output, beam flatness, in-plane and cross-plane symmetry, and beam quality were evaluated. RESULTS: The QUICKCHECKwebline and Daily QATM3 performed with maximum percent differences from baseline of -0.97% and 1.12% for output, 1.36% and 0.82% for flatness, 0.86% and -1.36% for in-plane symmetry, -1.41% and 1.00% for cross-plane symmetry, and -0.91% and 1.29% for beam quality respectively over all energies. CONCLUSION: Consistent and accurate measurements over a 4-month period, a user-friendly interface, and wireless features prove the QUICKCHECKwebline would be a suitable phantom for daily quality assurance use.
