Jump to ContentJump to Main Navigation
Show Summary Details
More options …

Radiology and Oncology

The Journal of Association of Radiology and Oncology

4 Issues per year


IMPACT FACTOR 2016: 1.681
5-year IMPACT FACTOR: 1.723

CiteScore 2016: 1.70

SCImago Journal Rank (SJR) 2016: 0.538
Source Normalized Impact per Paper (SNIP) 2016: 0.921


Open Access
Online
ISSN
1581-3207
See all formats and pricing
More options …
Volume 45, Issue 2 (Jun 2011)

Issues

Thyroid volume's influence on energy deposition from 131I calculated by Monte Carlo (MC) simulation

Ali Mowlavi
  • Department of Medical Physics, A.O.U. "Ospedali Riuniti di Trieste", Trieste, Italy
  • Physics Department, School of Sciences, Sabzevar Tarbat Moallem University, Sabzevar, Iran
/ Maria Fornasier
  • Department of Medical Physics, A.O.U. "Ospedali Riuniti di Trieste", Trieste, Italy
/ Mario de Denaro
  • Department of Medical Physics, A.O.U. "Ospedali Riuniti di Trieste", Trieste, Italy
Published Online: 2011-03-29 | DOI: https://doi.org/10.2478/v10019-011-0008-5

Thyroid volume's influence on energy deposition from 131I calculated by Monte Carlo (MC) simulation

Background. It is well known that the success of the radiomethabolic 131I treatment of hyperthyroidism could depend on the absorbed dose to the thyroid. It is, thus, very important to calculate the individual radiation dose as accurately as possible for different masses of thyroid lobes. The aim of this work is to evaluate the influence of thyroid volume on the energy deposition from beta and gamma rays of 131I by Monte Carlo (MC) simulation.

Materials and methods. We have considered thyroid lobes having an ellipsoidal shape, with a density of 1.05 g/cm3 and the material composition suggested by International Commission on Radiological Protection (ICRP). We have calculated the energy deposition of 131I rays for different volumes of thyroid lobes by using the MCNPX code, with a full transport of beta and gamma rays.

Results and conclusions. The results show that the total energy deposition has a significant difference, till 11%, when the lobe's volume varies from 1 ml to 25 ml, respect to the value presented in MIRDOSE for a 10 g sphere. The absorbed energy fraction increases by volume, because the increasing volume to surface ratio of ellipsoidal lobe causes the decrease of beta ray fraction escaping from the lobe.

Keywords: thyroid gland; 131I radionuclide; total energy deposition; MCNPX code

  • Traino AC, di Martino F, Lazzeri M, Stabin MG. Influence of thyroid volume reduction on calculated dose in radioiodine therapy of Graves' hyperthyroidism. Phys Med Biol 2000; 45: 121-29.Google Scholar

  • Becker DV. Choice of therapy for Graves' hyperthyroidism. N Eng J Med 1989; 311: 454-66.Google Scholar

  • Farrar JJ, Toft AD. Iodine-131 treatment of hyperthyroidism. Clin Endocrinol Oxf 1991; 35: 207-12.Google Scholar

  • Vardar E, Erkan N, Bayol U, Yılmaz C, Dogan M. Metastatic tumours to the thyroid gland: report of 3 cases and brief review of the literature. Radiol Oncol 2011; 45: 53-8.Web of ScienceGoogle Scholar

  • Van Isselt JW, de Klerk JMH, Van Rijk PP, Van Gils APG, Polman LJ, Kamphuis C, Meijer R, Beekman FJ. Comparison of methods for thyroid volume estimation in patients with Graves' disease. Eur J Nucl Med Mol Imaging 2003; 30: 525-31.CrossrefPubMedGoogle Scholar

  • Snyder W, Ford M, Warner G. Estimates of absorbed fractions for monoenergetic photon sources uniformly distributed in various organs of a heterogeneous phantom: MIRD pamphlet no. 5. J Nucl Med 1969; 10 (Suppl 3): 5-52.Google Scholar

  • Waters L S. MCNPX User's Manual, version 2.3.0. Los Alamos; 2002.Web of ScienceGoogle Scholar

  • http://www.orau.org/ptp/PTP%20Library/library/DOE/bnl/nuclidedata/MIRI131.htm

  • Eckerman KF, Westfall RJ, Ryman JC, Cristy M. Availability of nuclear decay data in electronic form, including beta spectra not previously published. Health Phys 1994; 67: 338-45.Google Scholar

  • Cember H, Johnson TE. Introduction to health physics. New York: McGraw-Hill; 2009.Google Scholar

About the article


Published Online: 2011-03-29

Published in Print: 2011-06-01


Citation Information: Radiology and Oncology, ISSN (Online) 1581-3207, ISSN (Print) 1318-2099, DOI: https://doi.org/10.2478/v10019-011-0008-5.

Export Citation

This content is open access.

Comments (0)

Please log in or register to comment.
Log in