Computation of beam quality parameters for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations in mammography.

Abstract:

:A computer program was implemented to predict mammography x-ray beam parameters in the range 20-40 kV for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations. The computation method used to simulate mammography x-ray spectra is based on the Boone et al. model. The beam quality parameters such as the half-value layer (HVL), the homogeneity coefficient (HC), and the average photon energy were computed by simulating the interaction of the spectrum photons with matter. The checking of this computation was done using a comparison of the results with published data and measured values obtained at the Netherlands Metrology Institute Van Swinden Laboratorium, National Institute of Standards and Technology, and International Atomic Energy Agency. The predicted values with a mean deviation of 3.3% of HVL, 3.7% of HC, and 1.5% of average photon energy show acceptable agreement with published data and measurements for all target/filter combinations in the 23-40 kV range. The accuracy of this computation can be considered clinically acceptable and can allow an appreciable estimation for the beam quality parameters.

journal_name

Med Phys

journal_title

Medical physics

authors

Kharrati H,Zarrad B

doi

10.1118/1.1608498

subject

Has Abstract

pub_date

2003-10-01 00:00:00

pages

2638-42

issue

10

eissn

0094-2405

issn

2473-4209

journal_volume

30

pub_type

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