Apparatus and method for count loss calibration of photon-counting detectors in spectral computed tomography imaging
AssigneesKabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
InventorsXiaolan Wang, Yu Zou
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Abstract
A method for photon count-loss calibration in a computed-tomography (CT) scanner, including capturing incident X-ray photons via a plurality of energy-discriminating detectors, determining photon counts of the captured incident X-ray photons in a plurality of energy windows at each energy-discriminating detector, and adjusting the determined photon counts in each energy window for each energy-discriminating detector based on a pre-determined photon count-loss look-up table and the determined photon counts.
Claims10
A method for photon count-loss calibration in a computed-tomography (CT) scanner, comprising:
- capturing incident X-ray photons via a plurality of energy-discriminating detectors;
- determining photon counts of the captured incident X-ray photons in a plurality of energy windows at each energy-discriminating detector;
- and
- adjusting the determined photon counts in each energy window for each energy-discriminating detector based on a pre-determined photon count-loss look-up table and a basis material decomposition obtained from the determined photon counts.
A computed-tomography (CT) apparatus, comprising:
- a CT scanner including an X-ray source;
- a detector including a plurality of energy-discriminating detectors capturing incident X-ray photons emitted from the X-ray source;
- and
- a processor configured to
- determine photon counts of the captured incident X-ray photons in a plurality of energy windows at each energy-discriminating detector, and
- adjust the determined photon counts in each energy window for each energy-discriminating detector based on a pre-determined photon count-loss look-up table and a basis material decomposition obtained from the determined photon counts.
A method to determine a photon count-loss look-up table for calibrating photon counts detected at a plurality of energy-discriminating detectors in a computed-tomography (CT) apparatus, the method comprising:
- emitting X-ray photons, under pre-determined scan parameters, from an X-ray source, to a phantom arranged within the CT apparatus, the phantom including a pre-determined basis material and having a pre-determined thickness;
- capturing incident X-ray photons at the plurality of energy-discriminating detectors;
- detecting the photon counts of the captured incident X-ray photons in a plurality of energy windows at each energy-discriminating detector;
- determining estimated true photon counts based on the pre-determined basis material, the pre-determined thickness, and the pre-determined scan parameters;
- and
- storing, in the photon count-loss look-up table, the determined estimated true photon counts and the detected photon counts in association with parameters representing the pre-determined basis material and the pre-determined thickness, and in association with the pre-determined scan parameters.
An apparatus to determine a photon count-loss look-up table for calibrating photon counts detected in a computed-tomography (CT) apparatus, the apparatus comprising:
- an X-ray source configured to emit X-ray photons, under pre-determined scan parameters, from an X-ray source, to a phantom arranged within the CT apparatus, the phantom including a pre-determined basis material and having a pre-determined thickness;
- a plurality of energy-discriminating detectors configured to capture incident X-ray photons and to detect the photon counts of the captured incident X-ray photons in a plurality of energy windows;
- a processor configured to determine estimated true photon counts based on the pre-determined basis material, the pre-determined thickness, and the pre-determined scan parameters;
- and
- a memory configured to store, in the photon count-loss look-up table, the determined estimated true photon counts and the detected photon counts in association with parameters representing the pre-determined basis material and the pre-determined thickness, and in association with the pre-determined scan parameters.
Dependencies are inferred from the claim text.