Method and apparatus for the reduction of artifacts in computed tomography images

A computed tomography system for reducing artifacts in image data, the artifacts being due to the presence of a high density object in a subject of interest, the system comprising:

• an x-ray source configured to project an x-ray beam from a plurality of positions through the subject of interest;
• a detector configured to produce a plurality of electrical signals corresponding to the x-ray beam;
• and
• a processor configured to process the plurality of electrical signals to generate measured sinogram data, the sinogram data representative of a plurality of measured sinogram elements, wherein the processor is further configured to reconstruct the measured sinogram data to generate initial reconstructed image data;
• identify a trace of the high density object in the measured sinogram data;
• identify a region of interest in the initial reconstructed image data;
• identify an optimization criterion based upon the region of interest, in an image domain;
• iteratively adjust the measured sinogram elements at least in the trace of the high density object in the measured sinogram based upon the optimization criterion in the image domain, to generate corrected sinogram data;
• and reconstruct the corrected sinogram data to generate improved reconstructed image data.

At least one computer-readable medium storing computer instructions for instructing a computer system to reduce artifacts in image data generated by a computed tomography system, the artifacts being due to the presence of a high density object in a subject of interest, the computer instructions comprising:

• receiving measured sinogram data from the computed tomography system, the sinogram data representative of a plurality of measured sinogram elements;
• reconstructing the measured sinogram data to generate initial reconstructed image data;
• identifying a trace of the high density object in the measured sinogram data;
• identifying a region of interest in the initial reconstructed image data;
• identifying an optimization criterion based upon the region of interest, in an image domain;
• iteratively adjusting the measured sinogram elements at least in the trace of the high density object in the measured sinogram data based upon the optimization criterion in the image domain, to generate corrected sinogram data;
• and
• reconstructing the corrected sinogram data to generate improved reconstructed image data.

A computed tomography system for reducing artifacts in image data, the artifacts being due to the presence of a high density object in a subject of interest, the system comprising:

• means for processing a plurality of electrical signals corresponding to an x-ray beam generated by the computed tomography system to generate measured sinogram data, the sinogram data representative of a plurality of measured sinogram elements, wherein the processing further comprises reconstructing the measured sinogram data to generate initial reconstructed image data;
• identify a trace of the high density object in the measured sinogram data;
• identify a region of interest in the initial reconstructed image data;
• identify an optimization criterion based upon the region of interest, in an image domain;
• iteratively adjust the measured sinogram elements at least in the trace of the high density object in the measured sinogram data based upon the optimization criterion in the image domain, to generate corrected sinogram data;
• and reconstruct the corrected sinogram data to generate improved reconstructed image data.

A method for reducing artifacts in image data generated by a computed tomography system, the artifacts being due to the presence of objects in a subject of interest, the method comprising:

• receiving measured sinogram data from the computed tomography system, the sinogram data representative of a plurality of measured sinogram elements;
• reconstructing the measured sinogram data to generate initial reconstructed image data;
• identifying a sinogram region of interest in the measured sinogram data;
• identifying an image region of interest in the initial reconstructed image data;
• identifying an optimization criterion based upon the image region of interest, in an image domain;
• iteratively adjusting the measured sinogram elements in at least the sinogram region of interest based upon the optimization criterion in the image domain, to generate corrected sinogram data;
• and
• reconstructing the corrected sinogram data to generate improved reconstructed image data.