Abstract：
:Monte Carlo methods have been applied to the study of the performance of antiscatter grids in radiography. Photon histories for imaging with a 20 cm thick water phantom irradiated with an 80 kV x-ray spectrum were generated by Monte Carlo simulation. The scattering and absorption of the photons transmitted from the phantom were traced in the grid. Grids were evaluated with strip densities ranging from 10 to 67 lines/cm, grid ratios from 6 to 15, and lead-to-interspace ratios from 1/9 to 1/2. The contrast improvement factor and the Bucky factor were used as the benefit and cost indicators, respectively, for evaluation of the grids. The dependence of these factors on the grid ratio, lead-to-interspace ratio, strip density, lead content, and interspace material was investigated. The results indicate that high-strip-density grids with thin lead strips and high grid ratios can provide higher contrast improvement factors than are achieved with low-strip-density grids, without an increase in patient exposure. This theoretical approach is useful for the prediction and development of optimal antiscatter grids for radiographic procedures.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Chan HP,Doi Kdoi
10.1088/0031-9155/27/6/002subject
Has Abstractpub_date
1982-06-01 00:00:00pages
785-803issue
6eissn
0031-9155issn
1361-6560journal_volume
27pub_type
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