Hippocampal sclerosis is a common cause of epilepsy, whereby a neuronal cell loss of more than 50% cells is characteristic. If medication fails the best possible treatment is the extraction of the diseased organ. To analyze the microanatomy of the diseased tissue we scanned a human hippocampus extracted from an epilepsy patient. After the identification of degenerated tissue using magnetic resonance imaging the specimen was reduced in size to fit into a cylindrical container with a diameter of 6 mm. Using synchrotron radiation and grating interferometry we acquired micro computed tomography datasets of the specimen. The present study was one of the first successful phase tomography measurements at the imaging beamline P05 (operated by HZG at the PETRA III storage ring, DESY, Hamburg, Germany). Ring and streak artefacts were reduced by enhanced flat-field corrections, combined wavelet-Fourier filters and bilateral filtering. We improved the flat-field correction by the consideration of the correlation between the projections and the flat-field images. In the present study, the correlation that was based on mean squared differences and evaluated on manually determined reference regions leads to the best artefact reduction. A preliminary segmentation of the abnormal tissue reveals that a clinically relevant study requires the development of even more sophisticated artifact reduction tools or a phase contrast measurement of higher quality.

Date Published: 9 October 2014
PDF: 8 pages
Proc. SPIE 9212, Developments in X-Ray Tomography IX, 92120S (9 October 2014); doi: 10.1117/12.2061582

Published in SPIE Proceedings Vol. 9212:
Developments in X-Ray Tomography IX
Stuart R. Stock, Editor(s)