Abstract：
:We employed an elastic reservoir filled with tissue-equivalent fluid as an x-ray beam filter for exposure equalization. The filter is designed to be placed between the upper compression plate and the breast. During compression, it will conform to the shape of the peripheral region of the breast and fill the space between the upper and lower compression plates, thereby reducing the variation in x-ray penetration between the thick and thin regions of the breast and compressing the dynamic range of the breast image. Results of a phantom study showed that the visibility of low-contrast features was improved in the peripheral region of the equalized breast phantom image. Experimental measurements indicated that the filter reduced scattered radiation in the peripheral region. This result was confirmed by a Monte Carlo simulation study. The radiation contrast, with the effect of beam hardening included, was also improved when equalization was employed.
journal_name
Med Physjournal_title
Medical physicsauthors
Lam KL,Chan HPdoi
10.1118/1.596502subject
Has Abstractpub_date
1990-03-01 00:00:00pages
242-9issue
2eissn
0094-2405issn
2473-4209journal_volume
17pub_type
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