Autor: |
Qiulin Tang, Jochen Cammin, Katsuyuki Taguchi, Neal E. Hartsough, Somesh Srivastava, William C. Barber, J.S. Iwanczyk |
Rok vydání: |
2012 |
Předmět: |
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Zdroj: |
SPIE Proceedings. |
ISSN: |
0277-786X |
DOI: |
10.1117/12.911217 |
Popis: |
Photon counting detectors are an emerging technology for spectral computed tomography. They have the potential to improve tissue contrast and specificity, reduce dose, and enable novel applications for K-edge and functional imaging. In this presentation various non-linear distortions were investigated that affect the image quality in photon-counting spectral CT: deadtime losses and spectral response, inherent to the new technology, and beam hardening artifacts that stem from the use of a polychromatic x-ray source. These effects were corrected or compensated for by performing calibration measurements. Techniques from material decomposition were applied to reconstruct images at a desired energy. Two methods were compared to synthesize a single monoenergetic image from photon counting data with multiple energy bins. The parameters were optimized to maximize a given image quality index. The procedures were evaluated on phantom data acquired on an experimental CT scanner with photon-counting detectors with two energy thresholds. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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