Open AccessSensitivity-based optimization for the design of a grating interferometer for clinical X-ray phase contrast mammography
Author(s) -
Carolina Arboleda,
Zhentian Wang,
Thomas Kœhler,
Géraldine Martens,
Udo van Stevendaal,
Matthias Bartels,
P. Villanueva-Pérez,
Ewald Roessl,
Marco Stampai
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.006349
Subject(s) - optics , grating , interferometry , sensitivity (control systems) , mammography , phase contrast imaging , astronomical interferometer , visibility , phase (matter) , contrast (vision) , physics , electronic engineering , medicine , cancer , quantum mechanics , breast cancer , phase contrast microscopy , engineering
An X-ray grating interferometer (GI) suitable for clinical mammography must comply with quite strict dose, scanning time and geometry limitations, while being able to detect tumors, microcalcifications and other abnormalities. Such a design task is not straightforward, since obtaining optimal phase-contrast and dark-field signals with clinically compatible doses and geometrical constraints is remarkably challenging. In this work, we present a wave propagation based optimization that uses the phase and dark-field sensitivities as figures of merit. This method was used to calculate the optimal interferometer designs for a commercial mammography setup. Its accuracy was validated by measuring the visibility of polycarbonate samples of different thicknesses on a Talbot-Lau interferometer installed on this device and considering some of the most common grating imperfections to be able to reproduce the experimental values. The optimization method outcomes indicate that small grating pitches are required to boost sensitivity in such a constrained setup and that there is a different optimal scenario for each signal type.