Energy filtering with X-ray lenses: optimization for photon-counting mammography.
Chromatic properties of the multi-prism and prism-array X-ray lenses (MPL and PAL) can potentially be utilized for efficient energy filtering and dose reduction in mammography. The line-shaped foci of the lenses are optimal for coupling to photon-counting silicon strip detectors in a scanning system. A theoretical model was developed and used to investigate the benefit of two lenses compared with an absorption-filtered reference system. The dose reduction of the MPL filter was approximately 15% compared with the reference system at matching scan time, and the spatial resolution was higher. The dose of the PAL-filtered system was found to be approximately 20% lower than for the reference system at equal scan time and resolution, and only approximately 20% higher than for a monochromatic beam. An investigation of some practical issues remains, including the feasibility of brilliant-enough X-ray sources and manufacturing of a polymer PAL.
Fredenberg
Erik
E
Department of Physics, Royal Institute of Technology, AlbaNova, Stockholm SE-106 91, Sweden. fberg@mi.physics.kth.se
Cederström
Björn
B
Danielsson
Mats
M
D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D007909:Lenses; D008327:Mammography / Q000295:instrumentation*; D010363:Pattern Recognition, Automated / Q000379:methods*; D017785:Photons; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity