Conversion coefficients based on the VIP-Man anatomical model and EGS4.

A new set of conversion coefficients from kerma free-in-air to absorbed dose and kerma free-in-air to "effective VIP-Man dose" has been calculated for external monoenergetic photon beams from 10 keV to 10 MeV using an image-based whole-body anatomical model. This model, called VIP-Man, was recently developed at Rensselaer from the high-resolution color images of the National Library of Medicine's Visible Human Project. An EGS4-based Monte Carlo user code, named EGS4-VLSI, was developed to efficiently process the extremely large image data in VIP-Man. Irradiation conditions include anterior-posterior, posterior-anterior, right lateral, left lateral, rotational, and isotropic geometries. Conversion coefficients from this study are compared with those obtained from two mathematical models, ADAM and EVA. "Effective VIP-Man doses" differ from the previously reported effective dose results by 10%-50% for photons between 100 keV and 10 MeV. Discrepancies are more significant at lower energies and for individual organ doses. Since VIP-Man is a realistic model that contains several tissues that were not previously defined well (or not available) in other models, the reported results offer an opportunity to improve the existing dosimetric data and the mathematical models.

[1]  A. Bozkurt,et al.  VIP-MAN: AN IMAGE-BASED WHOLE-BODY ADULT MALE MODEL CONSTRUCTED FROM COLOR PHOTOGRAPHS OF THE VISIBLE HUMAN PROJECT FOR MULTI-PARTICLE MONTE CARLO CALCULATIONS , 2000, Health physics.

[2]  W. Nelson,et al.  Monte Carlo Transport of Electrons and Photons , 1988 .

[3]  X. Xu,et al.  Fluence-to-dose conversion coefficients based on the VIP-Man anatomical model and MCNPX code for monoenergetic neutrons above 20 MeV. , 2001, Health physics.

[4]  K. F. Eckerman,et al.  Specific absorbed fractions of energy at various ages from internal photon sources: 6, Newborn , 1987 .

[5]  D. Rogers,et al.  EGS4 code system , 1985 .

[6]  W. S. Snyder,et al.  Estimates of absorbed fractions for monoenergetic photon sources uniformly distributed in various organs of a heterogeneous phantom. , 1974, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.

[7]  M Caon,et al.  An EGS4-ready tomographic computational model of a 14-year-old female torso for calculating organ doses from CT examinations. , 1999, Physics in medicine and biology.

[8]  G. Marsaglia,et al.  A New Class of Random Number Generators , 1991 .

[9]  A. Beddoe,et al.  Calculated dose factors for the radiosensitive tissues in bone irradiated by surface-deposited radionuclides. , 1978, Physics in medicine and biology.

[10]  M. Zankl,et al.  Calculation of the effective dose and its variation from environmental gamma ray sources. , 1998, Health physics.

[11]  A. Beddoe,et al.  Measurements of trabecular bone structure in man (for radionuclide dosimetry , 1976 .

[12]  M. Zankl,et al.  Voxel Anthropomorphic Models as a Tool for Internal Dosimetry , 1998 .

[13]  D. G. Jones A Realistic Anthropomorphic Phantom for Calculating Organ Doses Arising from External Photon Irradiation , 1997 .

[14]  F. Spiers TRANSITION-ZONE DOSIMETRY. , 1969 .

[15]  M. Zankl,et al.  Some critical remarks on the use of sex-specific tissue weighting factors for effective dose equivalent calculations. , 1997, Health physics.

[16]  X. Xu,et al.  Specific absorbed fractions from the image-based VIP-Man body model and EGS4-VLSI Monte Carlo code: internal electron emitters. , 2001, Physics in medicine and biology.

[17]  Kimiaki Saito,et al.  Organ Doses for Foetuses, Babies, Children and Adults from Environmental Gamma Rays , 1991 .

[18]  Xu Xg,et al.  Sex-specific tissue weighting factors for effective dose equivalent calculations. , 1996 .

[19]  G Drexler,et al.  Realistic computerized human phantoms. , 1994, Advances in space research : the official journal of the Committee on Space Research.

[20]  F. Spiers,et al.  Calculated beta-ray dose factors for trabecular bone. , 1976, Physics in medicine and biology.

[21]  P B Hoffer,et al.  Computerized three-dimensional segmented human anatomy. , 1994, Medical physics.

[22]  K F Eckerman,et al.  Electron absorbed fractions and dose conversion factors for marrow and bone by skeletal regions. , 1994, Health physics.

[23]  X. Xu,et al.  Fluence-to-dose conversion coefficients from monoenergetic neutrons below 20 MeV based on the VIP-Man anatomical model , 2000, Physics in medicine and biology.

[24]  X. Xu,et al.  Organ dose conversion coefficients for 0.1-10 MeV electrons calculated for the VIP-Man tomographic model. , 2001, Health physics.

[25]  Michael J. Ackerman,et al.  Accessing the Visible Human Project , 1995, D Lib Mag..

[26]  G Drexler,et al.  The construction of computer tomographic phantoms and their application in radiology and radiation protection , 1988, Radiation and environmental biophysics.