Extending the field of view in modulation-based X-ray phase microtomography

TL;DR

This paper presents a new image processing method that extends the field of view in modulation-based X-ray phase microtomography, enabling high-resolution imaging of larger biological samples.

Contribution

A novel combination of eigenflat optimization and deformable image registration to achieve quantitative imaging of centimeter-sized objects with micron resolution.

Findings

Successfully mapped electron density of a 15 mm rat brain sample.

Extended the effective field of view from 6 mm to larger sizes.

Demonstrated potential for biological and materials science applications.

Abstract

Recent advances in propagation-based phase-contrast imaging, such as hierarchical imaging, have enabled the visualization of internal structures in large biological specimens and material samples. However, modulation-based techniques, which provide quantitative electron density information, face challenges when imaging larger objects due to stringent beam stability requirements and detector distortions. Extending the field of view of these methods is crucial for obtaining comparable quantitative results across beamlines and adapting to the smaller beam profiles of fourth-generation synchrotron sources. We introduce a novel image processing technique combining an eigenflat optimization with deformable image registration to address the challenges and enable quantitative high-resolution scans of centimeter-sized objects with multiple-micrometer resolution. We demonstrate the potential of the method by obtaining an electron density map of a rat brain sample 15 mm in diameter despite the limited horizontal field of view of 6 mm of the beamline. This showcases the technique's ability to significantly widen the range of applications of modulation-based techniques in both biological and materials science research.