International Journal of Radiation Research

en Dosimetric response of the Delta4 system for small fields and the impact on dose verification accuracy Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;">Background: This study investigates the dosimetric response of the Delta4 system to varying field sizes and assesses its accuracy in dose verification. Materials and Methods: Output factors for fields ranging from 1 × 1 cm² to 20 × 20 cm² were measured using PTW 60019 detector, PTW 60018 detector, and the Delta4 system. The PTW 60019 measurements were considered the gold standard and were compared with those from the other two detectors. Two test plans were developed to compare the dose verification results of the Delta4 system, both with and without output factor correction. Results: The PTW 60018 and IBA CC13 detector measurements, using the daisy-chaining method, demonstrated strong agreement with the gold standard. However, the Delta4 system showed an underestimation in the output factor of the 1×1 cm² field, with deviations of -2.259% for the 6 MV flattening filter (FF) beam and -3.343% for the 6 MV flattening filter free (FFF) beam. After correcting the output factor, the gamma passes rate (3%/2mm) for test plan 2 featuring 1 × 1 cm² sub-fields improved from 67.3% to 95.7% for the 6 MV FF beam. Conclusions: The Delta4 system exhibits a dosimetric response issue when managing small fields. Output factor corrections are recommended for Delta4 dose verification results when dealing with field sizes less than 4 cm and a high number of sub-fields.</div> Radiometry, radiation dosage, Delta4, small field. 677 682 http://ijrr.com/browse.php?a_code=A-10-1-1383&slc_lang=en&sid=1 J. Zeng 7900319475328460031761 7900319475328460031761 No Department of Radiotherapy, Cancer center, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China L. Lu 7900319475328460031762 7900319475328460031762 No Department of Radiotherapy, Cancer center, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China X.Y. Liu 7900319475328460031763 7900319475328460031763 No Department of Radiotherapy, Cancer center, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China C.R. Hu 7900319475328460031764 7900319475328460031764 No Clinical Oncology School of Fujian Medical University, Fujian Cancer Hospital, Fuzhou, China J. Hong 7900319475328460031765 7900319475328460031765 No Department of Radiotherapy, Cancer center, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China F.B. Guo gfb803@fjmu.edu.cn 7900319475328460031766 7900319475328460031766 Yes Department of Radiotherapy, Cancer center, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China Y. Guo gyi@mail.ustc.edu.cn 7900319475328460031767 7900319475328460031767 No Department of Radiotherapy, Cancer center, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China