Münster 2017 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

ST: Fachverband Strahlen- und Medizinphysik

ST 4: Biomedical Imaging I

ST 4.5: Vortrag

Mittwoch, 29. März 2017, 17:45–18:00, JUR 1

X-Ray Grating Tomography without Phase-Retrieval — •Florian Schiffers1,2, Sebastian Käppler2, Shiyang Hu2, Jens Rieger1, Georg Pelzer1, Thilo Michel1, Christian Riess2, and Gisela Anton11Erlangen Centre for Astroparticle Physics, Friedrich-Alexander- Universität Erlangen-Nürnberg — 2Pattern Recognition Lab, Friedrich-Alexander-Universität Erlangen-Nürnberg

Traditional Talbot-Lau X-ray Phase-Contrast tomography requires prior phase-retrieval based on - for instance stepping of the analyzer grating G2. Since several exposures per projection angle are required, high dose needs to be applied and simple integration into a continuously rotating gantry is cumbersome.

For the next step into clinical application it is desirable to have a tomographic reconstruction algorithm requiring only one phase-step per projection angle. Former work proposed a maximum-likelihood-based algorithm modeling the phase-contrast image formation process using the object's attenuation, refractive and small-angle scattering properties simultaneously, allowing tomographic reconstruction without the need of prior phase-retrieval by phase-stepping.

In this work we improve convergence using a smoothed initial reconstruction obtained by Filtered Backprojection of an interpolated estimation of the three sinograms: Absorption, differential phase-contrast and dark field. We demonstrate reconstruction of tomographic data acquired using a Talbot-Lau interferometer without phase-stepping with a polychromatic beam source.

100% | Mobil-Ansicht | English Version | Kontakt/Impressum/Datenschutz
DPG-Physik > DPG-Verhandlungen > 2017 > Münster