Technical Design Considerations of a Human-Scale Talbot-Lau Interferometer for Dark-Field CT

Viermetz M, Gustschin N, Schmid C, Haeusele J, Noel PB, Proksa R, Loscher S, Koehler T, Pfeiffer F (2023)


Publication Type: Journal article

Publication year: 2023

Journal

Book Volume: 42

Pages Range: 220-232

Journal Issue: 1

DOI: 10.1109/TMI.2022.3207579

Abstract

Computed tomography (CT) as an important clinical diagnostics method can profit from extension with dark-field imaging, as it is currently restricted to X-rays' attenuation contrast only. Dark-field imaging allows access to more tissue properties, such as micro-structural texture or porosity. The up-scaling process to clinical scale is complex because several design constraints must be considered. The two most important ones are that the finest grating is limited by current manufacturing technology to a 4.8 μ m period and that the interferometer should fit into the CT gantry with minimal modifications only. In this work we discuss why an inverse interferometer and a triangular G1 profile are advantageous and make a compact and sensitive interferometer implementation feasible. Our evaluation of the triangular grating profile reveals a deviation in the interference pattern compared to standard grating profiles, which must be considered in the subsequent data processing. An analysis of the grating orientation demonstrates that currently only a vertical layout can be combined with cylindrical bending of the gratings. We also provide an in-depth discussion, including a new simulation approach, of the impact of the extended X-ray source spot which can lead to large performance loss and present supporting experimental results. This analysis reveals a vastly increased sensitivity to geometry and grating period deviations, which must be considered early in the system design process.

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How to cite

APA:

Viermetz, M., Gustschin, N., Schmid, C., Haeusele, J., Noel, P.B., Proksa, R.,... Pfeiffer, F. (2023). Technical Design Considerations of a Human-Scale Talbot-Lau Interferometer for Dark-Field CT. IEEE Transactions on Medical Imaging, 42(1), 220-232. https://dx.doi.org/10.1109/TMI.2022.3207579

MLA:

Viermetz, Manuel, et al. "Technical Design Considerations of a Human-Scale Talbot-Lau Interferometer for Dark-Field CT." IEEE Transactions on Medical Imaging 42.1 (2023): 220-232.

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