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arXiv · 2101.09435

A photon-counting detector for dual-energy breast tomosynthesis

Erik Fredenberg·Mats Lundqvist·Magnus Aslund·Magnus Hemmendorff·Bjorn Cederstrom·Mats Danielsson
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Abstract

We present the first evaluation of a recently developed silicon-strip detector for photon-counting dual-energy breast tomosynthesis. The detector is well suited for tomosynthesis with high dose efficiency and intrinsic scatter rejection. A method was developed for measuring the spatial resolution of a system based on the detector in terms of the three-dimensional modulation transfer function (MTF). The measurements agreed well with theoretical expectations, and it was seen that depth resolution was won at the cost of a slightly decreased lateral resolution. This may be a justifiable trade-off as clinical images acquired with the system indicate improved conspicuity of breast lesions. The photon-counting detector enables dual-energy subtraction imaging with electronic spectrumsplitting. This improved the detectability of iodine in phantom measurements, and the detector was found to be stable over typical clinical acquisition times. A model of the energy resolution showed that further improvements are within reach by optimization of the detector.

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Erik Fredenberg, Mats Lundqvist, Magnus Aslund, Magnus Hemmendorff, Bjorn Cederstrom, Mats Danielsson. 2021-01-23. A photon-counting detector for dual-energy breast tomosynthesis. https://doi.org/10.1117/12.813037

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