Radiation Protection Dosimetry Advance Access originally published online on July 29, 2008
Radiation Protection Dosimetry 2008 131(4):431-443; doi:10.1093/rpd/ncn200
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Assessment of patient organ doses and effective doses using the VIP-Man adult male phantom for selected cone-beam CT imaging procedures during image guided radiation therapy
1 Department of Nuclear Engineering and Engineering Physics, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
2 Department of Radiation Oncology, University of California, San Diego, La Jolla, CA 92093, USA
* Corresponding author: xug2{at}rpi.edu
Received April 10, 2008, amended June 26, 2008, accepted July 7, 2008
A Monte Carlo based computational procedure for determining organ doses and effective doses has been described for two procedures used in newly developed image-guided radiation treatment: kilovoltage cone-beam computed tomography (kV CBCT) and mega-voltage computed tomography (MV CBCT). A whole-body patient computational phantom, VIP-Man phantom, is employed for Monte Carlo dose calculations. Results indicate that the thyroid dose is always the highest in head and neck (H&N) scan for both kV and MV CBCT, and the bladder dose is the highest in prostate scan for both kV and MV CBCT. For the VIP-Man phantom, it has been found that the effective dose for kV CBCT (assuming a total exposure of 1350 mAs) is
9.5 mSv for the two anatomical sites, whereas the effective dose for MV CBCT (assuming a total of 6 monitor unit) ranges from 5.10 mSv for the H&N case to 8.39 mSv for the prostate scan. The estimated whole-body effective doses allow different imaging procedures to be compared and evaluated.