Abstract：
:A computer program was developed to calculate both integral absorbed dose in a water phantom and entrance exposure, for the imaging of iodine contrast with x-ray intensifying screens. The effect of filtration of the x-ray beam on integral absorbed dose and entrance exposure was studied for 27 different filter materials and four types of intensifying screens. The dose and exposure were calculated, keeping the image contrast and energy absorption in the screens constant. To check the validity of the calculations, a number of measurements were performed, the results of which agreed well with our calculations. A remarkable result is that dose and exposure reduction can be achieved almost equally well with conventional filters (aluminum and copper) as with a number of K-edge filters. This was found for situations commonly encountered in diagnostic radiology (60-80 kV, 20 cm water). This finding is in contrast to a number of earlier studies, in which K-edge filters were found to be superior to conventional filters.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Koedooder K,Venema HWdoi
10.1088/0031-9155/31/6/001subject
Has Abstractpub_date
1986-06-01 00:00:00pages
585-600issue
6eissn
0031-9155issn
1361-6560journal_volume
31pub_type
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