Filters for radiation reduction: a comparison.
Aluminum, yttrium, copper, and R-filters were evaluated with respect to effective beam energy, entrance radiation exposure to the skin, x-ray tube loading, and the quality of resultant radiographs. Since all filters yielded acceptable radiographs, a figure of merit was developed to determine which filter delivered the lowest entrance radiation exposure for the lowest increase in x-ray tube loading. The figure of merit indicated that the best results were obtained with the 0.1-mm Cu filter with 2 mm Al at 60-105 kVp and with the 0.2-mm Cu filter with 2 mm Al at 105-120 kVp. Cu filters produced radiographs with quality comparable to that of R- or Y filters. Cu filters are inexpensive alternatives to rare-earth filters and yielded a reduction in radiation exposure with less x-ray tube loading.
Kohn
M L
ML
Department of Medical Physics, Mercy Hospital, Scranton, PA 18501.
Gooch
A W
AW
Keller
W S
WS
D000535:Aluminum; D003300:Copper; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D008961:Models, Structural; D011829:Radiation Dosage; D011835:Radiation Protection / Q000295:instrumentation*; D015019:Yttrium
D015019:Yttrium; D003300:Copper; D000535:Aluminum