Abstract: A method for calibrating an imaging device comprising a photon counting detector (PCD), the method comprising: providing (i) an X-ray source configured to emit an X-ray beam, (ii) a first detector array configured to be in alignment with the X-ray beam, wherein the first detector array comprises a plurality of energy integrating detectors (EID) for detecting the X-ray beam emitted by the X-ray source, and (iii) a second detector array configured to be in alignment with the X-ray beam, wherein the second detector array comprises a plurality of photo counting detectors (PCD) for detecting the X-ray beam emitted by the X-ray source; detecting an X-ray beam passed through an object to be scanned with the plurality of energy integrating detectors (EID); recording the X-ray beam passed through the object to be scanned and detected by the plurality of energy integrating detectors (EID) as a first data set; detecting an X-ray beam passed through the object to be scanned with the plurality of photo counting detectors

Abstract: A method for correcting inaccuracies in a three-dimensional (3D) rendered volume of an object due to deviations between an actual scanner translation speed and an expected scanner translation speed, the method comprising: placing a pre-measured reference adjacent to the object which is being scanned so that the pre-measured reference and the object are in the same scan field; scanning the object and the pre-measured reference so that the object and the pre-measured reference are both incorporated in a 3D rendered volume produced through scanning; comparing the 3D rendered volume of the pre-measured reference against the 3D volume of the true pre-measured reference and generating a correction map indicative of how the rendered 3D volume of the pre-measured reference should be adjusted so as to produce a more accurate 3D rendering of the pre-measured reference; and using the correction map to adjust the rendered 3D volume of the object.

Abstract: A method for correcting inaccuracies in a three-dimensional (3D) rendered volume of an object due to deviations between an actual scanner translation speed and an expected scanner translation speed, the method comprising: placing a pre-measured reference adjacent to the object which is being scanned so that the pre-measured reference and the object are in the same scan field; scanning the object and the pre-measured reference so that the object and the pre-measured reference are both incorporated in a 3D rendered volume produced through scanning; comparing the 3D rendered volume of the pre-measured reference against the 3D volume of the true pre-measured reference and generating a correction map indicative of how the rendered 3D volume of the pre-measured reference should be adjusted so as to produce a more accurate 3D rendering of the pre-measured reference; and using the correction map to adjust the rendered 3D volume of the object.

Abstract: Methods for the correction of drive, tilt, and scanning-speed errors in imaging systems such as CT machines.

Abstract: A method for calibrating detectors in a CT scanner, wherein the new calibration process uses a combination of slab-based and water-based calibrations. By combining both calibrations, the complexity of each procedure can be reduced which will reduce restrictions on the quality of detectors used in the scanner. The slabs can be made out of commercially available material such as acrylic, and they will require no special treatment. Combining both calibrations also reduces the number of water phantoms needed for the calibration and the complexity of the calibration algorithm. Furthermore, the slabs can be shaped based on the scanner geometry so as to optimize the slab-based calibration step.

Abstract: Methods for the correction of drive, tilt and scanning speed errors in imaging systems such as CT machines.

Abstract: A method for calibrating detectors in a CT scanner, wherein the new calibration process uses a combination of slab-based and water-based calibrations. By combining both calibrations, the complexity of each procedure can be reduced which will reduce restrictions on the quality of detectors used in the scanner. The slabs can be made out of commercially available material such as acrylic, and they will require no special treatment. Combining both calibrations also reduces the number of water phantoms needed for the calibration and the complexity of the calibration algorithm. Furthermore, the slabs can be shaped based on the scanner geometry so as to optimize the slab-based calibration step.

Abstract: A method of decomposition of projection data is provided, wherein such projection data includes input projection data acquired using at least two x-ray spectra for a scanned object, including low energy projection data (PL) and high energy projection data (PH); the method comprises solving the projections PL and PH to determine a photoelectric line integral (Ap) component of attenuation and a Compton line integral (Ac) component of attenuation of the scanned object using a multi-step fitting procedure and constructing a Compton image Ic and a photoelectric image Ip from the Compton line integral and photoelectric line integral.

Abstract: A method of and apparatus for assessing the image quality of a CT scanner is described in which assessment can be made manually or automatically. No special image quality mode of CT scanner operation is necessary, and no precise alignment of the phantom is necessary. In general, performance of the scanner comprises: using the scanner (a) to scan a phantom in one or more of its normal modes of operation while translating said phantom along the scanner axis of rotation and (b) to produce scanned data of the phantom, and assessing the performance of the scanner from the scanned data. In accordance with another aspect, the assessment is performed by (a) using the scanner to scan a phantom in one or more of its normal modes of operation; (b) reconstructing a three-dimensional volume CT image for a region containing at least a portion of the phantom; (c) calculating properties of the CT image; and (d) using the calculated properties of the CT image to assess CT scanner performance.

Abstract: A method of reducing metal artifacts in a computed tomography (CT) system includes: A. generating a preliminary image from input projection data collected by the CT system; B. identifying metal objects in the preliminary image; C. generating secondary projections from the input projection data by removing projections of objects having characteristics that may cause the objects to be altered in a final artifact-corrected image. D. extracting the projections of metal objects identified in step B from the secondary projection data generated in step C. E. generating corrected projections by removing the projections of the metal objects extracted in Step D from the input projection data. F. generating a final image by reconstructing the corrected projections generated in step E and inserting the metal objects identified in Step B into the final image.