Improved computed radiography image quality from a BaFl:Eu photostimulable phosphor plate.
Recent advances in the design of photostimulable phosphor (PSP) plates for computed radiography (CR) systems have made it possible to manufacture plates made of BaFI:Eu phosphor material in the cassette form. The image quality of this plate, six BaF(Br,I):Eu plates, and one BaFBr:Eu plate were evaluated in terms of presampling modulation transfer function (MTF), normalized Wiener spectra (WSN), and detective quantum efficiency (DQE). Compared with the best-performing BaF(Br,I):Eu plate, the BaFI:Eu plate provided DQE that was higher, at spatial frequencies of 0.5, 1.0, and 2.0 cycles/mm, by 12% (21.8 versus 19.4), 13% (18.8 versus 16.7), and 11% (12.0 versus 10.8), respectively. Since presampling MTF values of the two plates were comparable, the BaFI:Eu plate's higher DQE is attributable to total WSN conversely being lower by 17% [8.65 x 10(-5) (mm2) versus 10.38 x 10(-5) (mm2)], 17% [5.85 x 10(-5) (mm2) versus 7.03 x 10(-5) (mm2)], and 12% [2.82 x 10(-5) (mm2) versus 3.19 x 10(-5) (mm2)] at the specified frequencies, respectively, primarily due to the contribution of x-ray quantum WSN. This jibes with the high x-ray absorption provided by the 27%-higher x-ray attenuation coefficients (7.54 versus 6.07, at 60 KeV) that BaFI offers over BaF(Br(0.85),I(0.15)), a result of the high atomic number of BaFI's exclusively iodine halide content. The results were consistent with earlier studies of several of these same plates and indicate that BaFI:Eu is a promising avenue to lower image noise and higher overall CR system image quality.
Nakano
Yasushi
Y
MG Imaging R&D Center, Konica Corporation, Hino-shi, Tokyo, Japan.
Gido
Tomonori
T
Honda
Satoshi
S
Maezawa
Akihiro
A
Wakamatsu
Hideaki
H
Yanagita
Takafumi
T
D017609:Barium Compounds; D001966:Bromine / Q000032:analysis; D005063:Europium; D005459:Fluorides; D007455:Iodine / Q000032:analysis; D008027:Light; D010758:Phosphorus / Q000737:chemistry*; D017785:Photons; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods*; D013057:Spectrum Analysis; D013679:Technology, Radiologic; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*; D014965:X-Rays
D017609:Barium Compounds; D010758:Phosphorus; D005063:Europium; D007455:Iodine; C055150:barium fluoride; D005459:Fluorides; D001966:Bromine