Investigating the effect on backscatter factor when measuring entrance surface dose using the raysafe X2 solid state...

Area of Science:

• Medical Physics
• Radiological Protection
• Diagnostic Imaging

Background:

• Patient dose assessment is crucial for radiation safety, with Entrance Surface Dose (ESD) being a key metric.
• Modern solid-state detectors hinder direct ESD measurement, necessitating alternative calculation methods.
• The IAEA recommends using backscatter factors (BSF) derived from Monte Carlo simulations for ESD estimation.

Purpose of the Study:

• To practically determine a reliable method for calculating BSF using a PMMA patient-equivalent phantom.
• To validate the use of BSFs for accurate ESD measurements with solid-state detectors.
• To support quality assurance protocols in diagnostic imaging.

Main Methods:

• Compared a solid-state detector with an ionization chamber sensitive to backscatter.
• Investigated BSF variations with radiation field size and beam quality.
• Utilized copper and aluminum filtration to simulate dose-reducing techniques.

Main Results:

• Demonstrated significant correspondence between calculated BSFs and established Monte Carlo data.
• Validated the use of a PMMA phantom for BSF determination.
• Showcased consistency with previous research using water and ICRU tissue-equivalent phantoms.

Conclusions:

• Proposed BSFs from this study for measuring ESD with RaySafe solid-state detectors and PMMA phantoms.
• Enhances accuracy in patient dose data acquisition during quality assurance.
• Facilitates reliable dose assessment with contemporary solid-state dosimetry equipment.