Radiation dose verification of an X-ray based blood irradiator using EBT3 radiochromic films calibrated using Gamma Knife machine

Abstract

Aim: Blood irradiators (BI) initial acceptance testing and routine annual dosimetry checks require radiation dose measurements in order to comply with regulatory requirements. Background: Traditionally thermoluminescence dosimeters (TLD) have been used to measure the dose. The EBT3 film is reported to be a better dosimeter for low energy X-rays than its predecessors EBT2 and EBT. To the best of our knowledge, the use of EBT3 films to perform dosimetry on X-ray based BI has not been reported yet. Materials and methods: We performed routine radiation dosimetry checks using EBT3 films on a new X-ray based BI and compared the results with TLD dosimetry. Calibration films were irradiated with radiation beam from a Co-60 Gamma Knife (GK) radiosurgery machine and, alternatively, using an Ir-192 high dose rate (HDR) brachytherapy device. The films were calibrated to cover a wide dose range from 1 to 40 Gy. Such a wide dose range has not been reported yet in BI film dosimetry. Results: We obtained a relative difference of about 6.6% between doses measured using TLD and those measured using EBT3 films. Both irradiation methods using GK or HDR were found to be adequate for the calibration of the EBT3 Gafchromic films. Conclusions: We recommend the use of EBT3 films in routine X-ray based BI dosimetry checks. The presented method takes advantage of available radiotherapy equipment that can be efficiently used for EBT3 films calibration. The method is fast, reproducible and saves valuable medical physicist's time.

Development of custom lead shield and strainer for targeted irradiation for mice in the gamma cell chamber

“…It measured the unknown dose based on the calibration of the standard curve. Soliman et al 14 , suggested that EBT3 provided more accurate results compared to TLD while Howard et al 15 indicated that EBT Gafchromic film provided more advantages to measure radiation dose. However, according to Najafi et al 16 , different findings were obtained on the dose measurement using Gafchromic film were due to the different factors such as the method for film digitation, the type of calibration curve used, or the uncertainty factor of gamma cell dose might cause deviation of the absorbed dose measurement.…”

Development of a Membrane Liquid-Based Thin-Layer Cell Film Maker

“…These models include the drive module of the stepper motor, the air pressure acquisition module, the liquid crystal communication and decoding module, the interpolation calculation module and so on. The user application calls these underlying driver functions in an orderly manner and performs corresponding operations according to the designed software workflow [24][25][26].…”

Diacetylene-Based Colorimetric Radiation Sensors for the Detection and Measurement of γ Radiation during Blood Irradiation

“…Therefore, film dosimetry is relatively simple, efficient, and less time-consuming. The commercially available Gafchromic film , (International Specialty Products, Inc., Wayne, NJ) has also been used for this purpose but it has several limitations like UV sensitivity, temperature sensitivity, and post irradiation instability. Also, its high cost restricts its use in routine dosimetry practice in the blood irradiator. − In this context, we have attempted to develop novel diacetylene (DA)-based colorimetric film dosimeters for the measurement of radiation dose and dose distribution in blood irradiation.…”