Holotomography versus X-ray grating interferometry: A comparative study

Abstract

International audienceX-ray phase-contrast imaging techniques are used at synchrotron facilities to visualize tiny density variations in bulk samples. They overcome the limitations of other non-destructive methods, which often provide insufficient spatial and/or density resolution. Holotomography (HT) and X-ray grating interferometry (XGI) are among the most powerful phase-contrast techniques. Here, we show a direct comparison of HT versus XGI. We find that XGI excels in fidelity of the density measurements and is more robust against low-frequency artifacts, while HT is superior in spatial resolution. This study gives indications for applications and developments of phase-contrast imaging

Implementation of a double-grating interferometer for phase-contrast computed tomography in a conventional system nanotom® m

“…The calculated value of formalin is q e,formalin ¼ (4.34 6 0.03) Â 10 29 electrons/m 3 and of cartilage q e,cartilage ¼ (4.56 6 0.03) Â 10 29 electrons/ m 3 . These values were determined as a mean intensity of a homogeneous volume of interest (VOIs) 6 standard deviation, see Fig.…”

“…The electron densities based on the data acquired at the imaging beamline ID19 (ESRF, France), 7 calculated as a mean intensity 6 standard deviation within VOIs comprising 120 Â 20 Â 100 voxels within each disc, are q e,PP ¼ (3.14 6 0. 3 . In our case, the measured electron densities were overestimated with a mean offset of (0.86 6 0.08) Â 10 29 electrons/m 3 .…”

“…In the hard X-ray regime, phase contrast is often preferred over conventional absorption contrast for soft tissue imaging 3,4 and visualizing weak X-ray absorbing species in the direct neighborhood of stronger absorbing components, 5 in particular, for three-dimensional imaging of a cartilage which is involved in the degenerative changes of a joint, [6][7][8][9][10] providing imaging data of morphological features with unprecedented contrast. Disorders associated with cartilage degeneration, such as debilitating joint diseases, are one of the leading causes of disability worldwide.…”

3d virtual histology of neuronal tissue by propagation-based x-ray phase-contrast tomography

“…Talbot interferometry, edge illumination and speckle-based imaging provide excellent contrast and model-independent fully automatic reconstructions of the phase, amplitude and darkfield signal separately. Compared to other techniques, they provide a very high density resolution with accurately retrieved values of the complex index of refraction [197]. However, spatial resolution is limited to the range of few micrometers [137,197,199] and phase-stepping is necessary for high quality reconstructions, although also single-step approaches have been proposed, leading to the need of additional a priori knowledge or a decrease in spatial resolution [14,15,196].…”

“…Compared to other techniques, they provide a very high density resolution with accurately retrieved values of the complex index of refraction [197]. However, spatial resolution is limited to the range of few micrometers [137,197,199] and phase-stepping is necessary for high quality reconstructions, although also single-step approaches have been proposed, leading to the need of additional a priori knowledge or a decrease in spatial resolution [14,15,196]. Moreover, in Talbot interferometry and edge illumination radiation dose is increased due to absorbing optical elements behind the sample and imperfections in these elements as well as their alignment might alter the reconstruction quality [197].…”