Determine the Dose Distribution Using Ultrasound Parameters in MAGIC-f Polymer Gels

作者:Masoumi Hossein; Mokhtari Dizaji Manijhe*; Arbabi Azim; Bakhshandeh Mohsen
来源:Dose-Response, 2016, 14(1): 155932581562564.
DOI:10.1177/1559325815625647

摘要

In this study, using methacrylic and ascorbic acid in gelatin initiated by copper (MAGIC-f) polymer gel after megavoltage energy exposure, the sensitivity of the ultrasound velocity and attenuation coefficient dose-dependent parameters was evaluated. The MAGIC-f polymer gel was irradiated under 1.25 MeV cobalt-60, ranging from 0 to 60 Gy in 2-Gy steps, and received dose uniformity and accuracy of +/- 2%. After calibration of the ultrasonic systems with a frequency of 500 kHz, the parameters of ultrasound velocity and attenuation coefficient of the irradiated gel samples were measured. According to the dose-response curve, the ability of ultrasonic parameters was evaluated in dose rate readings. Based on a 4-order polynomial curve, fitted on the dose-response parameters of ultrasound velocity and attenuation coefficient and observed at 24 hours after irradiation, ultrasonic parameters had more sensitivity. The sensitivity of the dose-velocity and dose-attenuation coefficient curves was observed as 50 m/s/Gy and 0.06 dB/MHz/Gy over the linear range of 4 to 44 Gy, respectively. The ultrasonic parameters at 5 degrees C, 15 degrees C, and 25 degrees C on the gel dosimeter after 0 to 60 Gy irradiation showed that readings at 25 degrees C have higher sensitivity compared to 15 degrees C and 5 degrees C. Maximum sensitivity time and temperature readings of the MAGIC-f ultrasonic parameters were concluded 24 hours after irradiation and at a temperature of 25 degrees C.

  • 出版日期2016-3