The Effectiveness of Silicone-Based Non-Lead Nanoparticles for Radiation Protection of Patients in Diagnostic Radiology by Monte Carlo Simulation

Document Type : Original Article (s)

Authors

1 Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Medical Physics, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

3 Assistant Professor, Department of Medical Physics, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran

4 Professor, Department of Medical Physics, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

5 Professor, Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Using computed tomography (CT) scan may cause complications in the eye lens, thyroid gland, and breasts. One of the radiation protection methods to protect patients from unnecessary and unintended exposures is utilizing non-lead shields in CT-scan tests. Before designing and using these shields, it is necessary to study their performance by a simulation.Methods: Bismuth, tungsten, and tin with absorption edges in diagnostic radiology energy ranges were selected for this research. Each of the metals along with the silicon was used as building blocks in the Monte Carlo simulation. To determine the mass attenuation coefficient of the samples, the beam was simulated as single energy. The energy range was selected according to the common imaging tests in diagnostic laboratories from 20 to 140 keV with 20 keV steps. The flat photon source with a radius of 5 mm was placed at the origin of the geometry. Information obtained from the simulation could specify that the shield had the most attenuation coefficient at which energies.Findings: The shield containing 10% bismuth and 90% silicon showed more attenuation in the energies above 100 keV. Tungsten and tin shields also showed greater attenuation at medium and low energies.Conclusion: By using the effect of attenuation window and selecting proper percentage and metal for the energy applied in diagnostic radiology, patients can be protected from radiation exposure to radiosensitive superficial organs.

Keywords


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