Monte Carlo simulations of dose from microCT imaging procedures in a realistic mouse phantom

doi:10.1118/1.2148333

Title: Monte Carlo simulations of dose from microCT imaging procedures in a realistic mouse phantom

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Abstract

The purpose of this work was to calculate radiation dose and its organ distribution in a realistic mouse phantom from micro-computed tomography (microCT) imaging protocols. CT dose was calculated using GATE and a voxelized, realistic phantom. The x-ray photon energy spectra used in simulations were precalculated with GATE and validated against previously published data. The number of photons required per simulated experiments was determined by direct exposure measurements. Simulated experiments were performed for three types of beams and two types of mouse beds. Dose-volume histograms and dose percentiles were calculated for each organ. For a typical microCT screening examination with a reconstruction voxel size of 200 {mu}m, the average whole body dose varied from 80 mGy (at 80 kVp) to 160 mGy (at 50 kVp), showing a strong dependence on beam hardness. The average dose to the bone marrow is close to the soft tissue average. However, due to dose nonuniformity and higher radiation sensitivity, 5% of the marrow would receive an effective dose about four times higher than the average. If CT is performed longitudinally, a significant radiation dose can be given. The total absorbed radiation dose is a function of milliamperes-second, beam hardness, and desired image quality (resolution,more »« less

Authors:

Taschereau, Richard; Chow, Patrick L.; Chatziioannou, Arion F. ^[1]

Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, University of California School of Medicine, 700 Westwood Boulevard, Los Angeles, California 90095 (United States)

Publication Date:: Sun Jan 15 00:00:00 EST 2006

OSTI Identifier:: 20774974

Resource Type:: Journal Article

Resource Relation:: Journal Name: Medical Physics; Journal Volume: 33; Journal Issue: 1; Other Information: DOI: 10.1118/1.2148333; (c) 2006 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)

Country of Publication:: United States

Language:: English

Subject:: 62 RADIOLOGY AND NUCLEAR MEDICINE; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BONE MARROW; COMPUTERIZED SIMULATION; COMPUTERIZED TOMOGRAPHY; ENERGY SPECTRA; IMAGES; MICE; MONTE CARLO METHOD; PHANTOMS; PHOTONS; RADIATION DOSES; SENSITIVITY

Citation Formats


                    Taschereau, Richard, Chow, Patrick L., and Chatziioannou, Arion F. Monte Carlo simulations of dose from microCT imaging procedures in a realistic mouse phantom.  United States: N. p., 2006. 
        Web.  doi:10.1118/1.2148333.

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                    Taschereau, Richard, Chow, Patrick L., & Chatziioannou, Arion F. Monte Carlo simulations of dose from microCT imaging procedures in a realistic mouse phantom.  United States.  doi:10.1118/1.2148333.

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                    Taschereau, Richard, Chow, Patrick L., and Chatziioannou, Arion F. Sun .  
        "Monte Carlo simulations of dose from microCT imaging procedures in a realistic mouse phantom".  United States.  
        doi:10.1118/1.2148333.

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@article{osti_20774974,

  title        = {Monte Carlo simulations of dose from microCT imaging procedures in a realistic mouse phantom},

  author       = {Taschereau, Richard and Chow, Patrick L. and Chatziioannou, Arion F.},

  abstractNote = {The purpose of this work was to calculate radiation dose and its organ distribution in a realistic mouse phantom from micro-computed tomography (microCT) imaging protocols. CT dose was calculated using GATE and a voxelized, realistic phantom. The x-ray photon energy spectra used in simulations were precalculated with GATE and validated against previously published data. The number of photons required per simulated experiments was determined by direct exposure measurements. Simulated experiments were performed for three types of beams and two types of mouse beds. Dose-volume histograms and dose percentiles were calculated for each organ. For a typical microCT screening examination with a reconstruction voxel size of 200 {mu}m, the average whole body dose varied from 80 mGy (at 80 kVp) to 160 mGy (at 50 kVp), showing a strong dependence on beam hardness. The average dose to the bone marrow is close to the soft tissue average. However, due to dose nonuniformity and higher radiation sensitivity, 5% of the marrow would receive an effective dose about four times higher than the average. If CT is performed longitudinally, a significant radiation dose can be given. The total absorbed radiation dose is a function of milliamperes-second, beam hardness, and desired image quality (resolution, noise and contrast). To reduce dose, it would be advisable to use the hardest beam possible while maintaining an acceptable contrast in the image.},

  doi          = {10.1118/1.2148333},

  journal      = {Medical Physics},

  number       = 1,

  volume       = 33,

  place        = {United States},

  year         = {Sun Jan 15 00:00:00 EST 2006},

  month        = {Sun Jan 15 00:00:00 EST 2006}

}

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DOI: 10.1118/1.2148333

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