SU‐E‐T‐486: In Vivo Skin Dosimetry Using the Exradin W1 Plastic Scintillation Detector for Passively Scattered Proton Beam Therapy

• DOI: 10.1118/1.4924848
• Publication Date: 2015-06-29T18:11:13Z
• Authors: F Alsanea; L Wootton; R Kudchadker; M Usama; S Beddar
• Keywords: Dose profile

Purpose: To evaluate the accuracy and usefulness of plastic scintillation detectors used for skin dosimetry patients undergoing passive scatter proton therapy. Methods: Following an IRB approved protocol, six passively scattered beam therapy prostate cancer were selected in vivo using Exradin W1 scintillator. The detector was calibrated on a Cobalt‐60 unit, phantom measurements with parallel plate ion chamber to account under‐response due high LET at energies treatment. Measurements made heated water tank temperature dependence. For measurements, is fixed patient's medical tape center each two laterally opposed treatment fields. will be performed once per week patient duration treatment, total thirty measurements. measured dose compared expected dose, extracted from Eclipse planning system. average difference over all per‐patient computed, as well standard deviations. Results: exhibited 7% 225 250 MeV beams, 4% when 37 °C (relative response calibration 20 °C). Patient are ongoing. Conclusion: scintillator strong candidate beams PSDs equivalent very small (2mm diameter), permitting accurate that do not perturb delivered dose. This project supported part by award number CA182450 National Cancer Institute.