Experiment
The KEST (K-Edge Spectral micro-Tomography) project aims at proposing a K-edge Computed Tomography (CT) setup based on a conventional X-ray source and the photon counting CdTe detector Pixirad-I/Pixie-III. With accurate tuning of energy thresholds and source settings, the proposed setup is able to produce in a single exposure two images (one above and one below) the K-edge of a specific element, such as e.g. a contrast agent. Doing so, the contrast and virtual non-contrast images are available in a single acquisition. This opens to potential applications of this technique for in vivo spectral small animals imaging.
Figure 1. Sketch of the test object prepared for CT spectral imaging (on the left); Order and composition of the considered pipettes as results from an axial CT slice (on the right).
Figure 2. CT axial slices (512x512 pixels) collected with accurate tuning of the detector energy thresholds: low-energy image (on the left); high-energy image (on the right).
Figure 3. K-Edge Subtraction (KES) image where only iodine is highlighted (on the left) and color overlay over the combination of low and high images.
Publications
International journals
Brun, F. et al. Edge-subtraction X-ray ptychographic imaging with pink beam synchrotron radiation and a single photon-counting detector (2020) Scientific Reports, 10 (1), art. no. 6526.
Di Trapani, V. et al. Characterization of the acquisition modes implemented in Pixirad-1/Pixie-III X-ray Detector: Effects of charge sharing correction on spectral resolution and image quality (2020) NIM A, 955, art. no. 163220.
Brun, F. et al. Single-shot K-edge subtraction x-ray discrete computed tomography with a polychromatic source and the Pixie-III detector (2020) Physics in Medicine and Biology, 65 (5), art. no. 055016.
Brun, F. et al. Post-reconstruction 3D single-distance phase retrieval for multi-stage phase-contrast tomography with photon-counting detectors (2019) Journal of Synchrotron Radiation, 26 (2), pp. 510-516.
Brun, F. et al. Inpainting approaches to fill in detector gaps in phase contrast computed tomography (2018) Measurement Science and Technology, 29 (1), art. no. 014001.
Conference proceedings
Brun, F. et al. Towards in vivo K-edge X-ray micro-CT with the Pixirad-I/Pixie-III detector (2019) IFMBE Proceedings, 68 (1), pp. 123-126.
Di Trapani et al. Characterization of noise and efficiency of the Pixirad-1/Pixie-III CdTe X-ray imaging detector (2018) Journal of Instrumentation, 13 (12), art. no. C12008.
Brun, F. et al. K-edge spectral computed tomography with a photon counting detector and discrete reconstruction (2018) Proceedings of the Annual International Conference of the IEEE EMBC, art. no. 8513425.
Collaborators
Official beamtime has been awarded at Elettra, ESRF, and Diamond Light Source.
Contacts
For more information please contact: francesco.brun@ts.infn.it.