Systems, devices, and methods for multisource volumetric spectral computed tomography

A method for performing volumetric spectral computed tomography (CT) imaging of an object, the method comprising:

• providing a volumetric spectral computed tomography imaging device comprising:
• an x-ray source array comprising M numbers of spatially distributed x-ray focal spots;
• an x-ray beam confiner attached to the x-ray source array, wherein the x-ray beam confiner contains an array of apertures, each configured to confine the x-ray radiation from a corresponding x-ray focal spot to a fan beam having a narrow cone angle that illuminates a corresponding segment of the object to be imaged;
• a digital area x-ray detector configured to detect x-ray radiation and form an x-ray image of the object being imaged, wherein the digital area x-ray detector is positioned on an opposite side of the object with respect to the x-ray source array;
• and
• a gantry configured to rotate the x-ray source array and the digital area x-ray detector around the object, wherein the spatially distributed x-ray focal spots are substantially aligned along a direction of a rotation axis of the gantry;
• activating the M numbers of x-ray focal spots to scan the object N times;
• rotating the gantry around the object while the x-ray focal spots are activated;
• filtering radiation from each focal spot by a corresponding spectral filter;
• and
• processing, using one or more processors, N×M projection images to reconstruct a volumetric CT image of the object.

A dual-energy computed tomography (CT) imaging device comprising:

• an x-ray generator comprising an x-ray source, which has at least one cathode and at least one anode and is configured to emit x-ray radiation from first and second focal spots for imaging an object, and first and second spectral filters, wherein the first spectral filter is configured to filter the x-ray radiation from the first focal spot to produce low-energy (LE) x-ray radiation with a low mean energy, and wherein the second spectral filter is configured to filter the x-ray radiation from the second focal spot to produce high-energy (HE) x-ray radiation, the HE x-ray radiation having a higher mean energy than the LE x-ray radiation;
• an x-ray beam collimator that is configured to confine the LE x-ray radiation and the HE x-ray radiation to substantially a same region of interest on, in, and/or about the object;
• an x-ray detector configured to detect x-ray radiation and form an x-ray image of the object, wherein the x-ray detector is positioned on a different side of the object relative to the x-ray source;
• a gantry configured to rotate the x-ray source and the x-ray detector around the object;
• a controller that is configured to:
• activate the LE x-ray radiation and the HE x-ray radiation multiple times in an alternating exposure pattern as the x-ray source and the x-ray detector are rotated about the object, such that an LE projection image of the object is recorded by the x-ray detector for each exposure of the LE x-ray radiation and an HE projection image of the object is recorded by the x-ray detector for each exposure of the HE x-ray radiation;
• and
• activate and program an exposure level of the LE x-ray radiation and an exposure level of the HE x-ray radiation, wherein the exposure level of the LE x-ray radiation is independent of the exposure level of the HE x-ray radiation;
• and
• one or more processors configured to reconstruct dual-energy CT images of the object using the LE projection images and the HE projection images.

A multi-energy computed tomography (CT) imaging device comprising:

• an x-ray source, which has at least one cathode and at least one anode and is configured to emit x-ray radiation from a plurality of focal spots for imaging an object;
• a plurality of spectral filters, each of which is positioned such that the x-ray radiation emitted from each of the plurality of focal spots is filtered by a corresponding one of the plurality of spectral filters to produce radiation with a unique spectrum;
• an x-ray beam collimator that is configured to confine the x-ray radiation emitted from each of the plurality of focal spots to substantially a same region of interest on, in, and/or about the object;
• an x-ray detector configured to detect x-ray radiation and form an x-ray image of the object, wherein the x-ray detector is positioned on a different side of the object relative to the x-ray source;
• a gantry configured to rotate the x-ray source and the x-ray detector around the object;
• a controller that is configured to:
• activate the x-ray source to provide the x-ray radiation from one of the plurality of focal points multiple times in a sequential exposure pattern as the x-ray source and the x-ray detector are rotated about the object, such that a projection image of the object is recorded by the x-ray detector for each exposure of the x-ray radiation;
• and
• activate and program an exposure level of the x-ray exposures from one or more of the plurality of focal spots sequentially, wherein the exposure level of each of x-ray radiations is independent of others of the x-ray radiations;
• and
• one or more processors configured to reconstruct multi-energy CT images of the object using the projection images.

A volumetric computed tomography (CT) scanner comprising:

• an x-ray source array comprising M numbers of spatially distributed x-ray focal spots enclosed in a same evacuated housing, wherein the spatially distributed x-ray focal spots are aligned along an axis of rotation of the scanner;
• an x-ray beam collimator comprising an array of apertures, wherein each aperture of the array of apertures is aligned with, and configured to confine x-ray radiation from, a corresponding one of the spatially distributed x-ray focal spots of the x-ray source array, such that the x-ray radiation from the corresponding one of the spatially distributed x-ray focal spots to form a fan beam shape with a narrow cone angle to illuminate a corresponding segment of an imaged object;
• a digital area x-ray detector configured to detect x-ray radiation to form an x-ray image of the imaged object;
• a gantry configured to rotate the x-ray source array and the digital area x-ray detector around the object;
• an electronic controller configured to activate and regulate exposures of the x-ray radiation from each of the spatially distributed x-ray focal spots to illuminate the imaged object N times from each of the spatially distributed focal spot as the gantry rotates around the imaged object to produce a quantity of N×M raw projection images;
• and
• one or more processors configured to process the quantity of N×M raw projection images to reconstruct a volumetric CT image of the imaged object.