Energy filtering with X-ray lenses: optimization for photon-counting mammography

TL;DR

This paper investigates the use of X-ray multi-prism and prism-array lenses for energy filtering in photon-counting mammography, showing potential for dose reduction and improved resolution through theoretical modeling.

Contribution

It introduces a theoretical model to evaluate the benefits of MPL and PAL X-ray lenses for dose reduction and resolution enhancement in mammography.

Findings

MPL lens achieves ~15% dose reduction with higher spatial resolution.

PAL lens achieves ~20% dose reduction, comparable to monochromatic beams.

Practical issues like source brilliance and lens manufacturing remain to be addressed.

Abstract

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 ~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 ~20% lower than for the reference system at equal scan time and resolution, and only ~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.