Calculation of absorbed doses from computed tomography in pelvic phantom using Monte Carlo Simulation
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Abstract
Background: Computed Tomography (CT) is an effective diagnosis method which deposits high absorbed doses on internal organs; therefore, it is necessary to understand dosimetry nature of this method.
Objectives: To improve CT absorbed dose estimation by using a more appropriate phantom representing a human body and a Monte Carlo transport code.
Materials and methods: The Monte Carlo N-Particle transport code Version 5 or MCNP5 is used in this study to simulate a Rando phantom representing pelvic section of a patient in a CT procedure. Absorbed doses of various internal organs from MCNP5 are compared with standard experimental measurements based on the InLight nanoDot dosimeters.
Results: CT absorbed dose between MCNP5 simulation and standard experiment measurement are mostly in reasonable agreements within 10-percent discrepancy except those at skin positions.
Conclusion: Further study is recommended for calculating absorbed doses at skin positions, MCNP5 is practically reliable for estimating absorbed doses in a number of internal organs. The MCNP5 simulation is one of alternative method to evaluate patient radiation dose which helps radiology team manage diagnosis and treatment planning.
Article Details
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Personal views expressed by the contributors in their articles are not necessarily those of the Journal of Associated Medical Sciences, Faculty of Associated Medical Sciences, Chiang Mai University.
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