Optimization of the composition of phantom materials for computed tomography.
Using available data for photon attenuation and tissue composition, a computer code was developed for the optimization of the composition of phantom materials for diagnostic radiology. The code allows selection of attenuation data in a photon energy range from 1 to 150 keV and the choice of a suitable weight function in the energy interval chosen. For applications in CT imaging a weight function is available reflecting the contribution of the x-ray spectrum to the CT-signal. Several phantom materials for CT were optimized (body fat, trabecular bone, an average bone composition for C4 vertebrae and water) by varying the mineral components in a polymer base in order to adjust x-ray attenuation properties. Measurements with the water equivalent material (PSPP1) showed good agreement of calculated and measured HU values (AHU = 7.3 +/- 5.3 at 80 kVp and 4.0 +/- 2.7 at 140 kVp) and little variation of HU for tube voltages from 80 to 140 kVp. The method provides a fast and flexible means for obtaining optimized phantom materials for a large variety of tissue compositions and energy ranges.
Homolka
P
P
Department of Biomedical Engineering and Physics, University of Vienna, Austria. peter.homolka@univie.ac.at
Gahleitner
A
A
Prokop
M
M
Nowotny
R
R
D000273:Adipose Tissue / Q000000981:diagnostic imaging; D040761:Biomimetic Materials; D001842:Bone and Bones / Q000000981:diagnostic imaging; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging; D017076:Computer-Aided Design; D004867:Equipment Design / Q000379:methods; D006801:Humans; D008422:Materials Testing / Q000379:methods*; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D011108:Polymers; D011786:Quality Control; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*; D014867:Water
D011108:Polymers; D014867:Water