X-ray imaging in absorption contrast mode is well established for hard tissue visualization. However, performance
for lower density materials is limited due to a reduced contrast. Our aim is three-dimensional (3D)
characterization of micro-morphology of human brain tissues down to (sub-)cellular resolution within a laboratory
environment. Using the laboratory-based microtomography (μCT) system nanotom m (GE Sensing
and Inspection Technologies GmbH, Wunstorf, Germany) and synchrotron radiation at the Diamond-Manchester
Imaging Branchline I13-2 (Diamond Light Source, Didcot, UK), we have acquired 3D data with a resolution
down to 0.45 μm for visualization of a human cerebellum specimen down to cellular level. We have shown that
all selected modalities, namely laboratory-based absorption contrast micro-tomography (LBμCT), synchrotron
radiation based in-line single distance phase contrast tomography (SDPR) and synchrotron radiation based
single-grating interferometry (GI), can reach cellular resolution for tissue samples with a size in the mm-range.
The results are discussed qualitatively in comparison to optical microscopy of haematoxylin and eosin (HE)
stained sections. As phase contrast yields to a better data quality for soft tissues and in order to overcome
restrictions of limited beamline access for phase contrast measurements, we have equipped the μCT system
nanotom m with a double-grating phase contrast set-up. Preliminary experimental results of a knee sample
consisting of a bony part and a cartilage demonstrate that phase contrast data exhibits better quality compared
to absorption contrast. Currently, the set-up is under adjustment. It is expected that cellular resolution would
also be achieved. The questions arise (1) what would be the quality gain of laboratory-based phase contrast in
comparison to laboratory-based absorption contrast tomography and (2) could laboratory-based phase contrast
data provide comparable results to synchrotron radiation based phase contrast data.
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