Reconstruction of 3D image datasets from x-ray and cone-beam data

A method for reconstructing a 3D image dataset of an object with an imaging system having an X-ray source and an x-ray detector, comprising:

• acquiring a series of two-dimensional arrays of cone beam data from the x-ray detector while the x-ray source moves along a planar trajectory around the object, the trajectory being described by a series of source points serially numbered by a counter parameter;
• differentiating the acquired cone beam data with respect to the counter parameter of the trajectory at a fixed x-ray ray direction to produce a derivative of the cone beam data;
• filtering the derivative with a Hilbert-like filter to produce a filtered cone beam data;
• multiplying the acquired cone beam data with a redundancy weighting function before the differentiating step or multiplying the filtered cone beam data with the redundancy weighting function after the filtering step to produce a processed cone beam data;
• and
• back-projecting the processed cone beam data for reconstructing the 3D image dataset.

An imaging system for producing a 3D image dataset of an object, comprising:

• an x-ray source for emitting photon rays in a cone beam;
• an x-ray detector comprising a two-dimensional array of detector elements for acquiring a series of two-dimensional arrays of cone beam data while the x-ray source moves along a planar trajectory around the object, the trajectory being described by a series of source points serially numbered by a counter parameter;
• and
• an image reconstruction system for reconstructing the 3D image dataset by:
• differentiating the acquired cone beam data with respect to the counter parameter of the trajectory at a fixed x-ray ray direction to produce a derivative of the cone beam data;
• filtering the derivative with a Hilbert-like filter to produce a filtered cone beam data;
• multiplying the acquired cone beam data with a redundancy weighting function before the differentiating step or multiplying the filtered cone beam data with the redundancy weighting function after the filtering step to produce a processed cone beam data;
• and
• back-projecting the processed cone beam data for reconstructing the 3D image dataset.

A computer program stored on a computer for producing a 3D image dataset of an object, wherein, when executed on the computer, the program performs the following steps comprising:

• accessing a series of two-dimensional arrays of cone beam data acquired by an x-ray detector while an x-ray source moves along a planar trajectory around the object, the trajectory being described by a series of source points serially numbered by a counter parameter;
• differentiating the acquired cone beam data with respect to the counter parameter of the trajectory at a fixed x-ray ray direction to produce a derivative of the cone beam data;
• filtering the derivative with a Hilbert-like filter to produce a filtered cone beam data;
• multiplying the acquired cone beam data with a redundancy weighting function before the differentiating step or multiplying the filtered cone beam data with the redundancy weighting function after the filtering step to produce a processed cone beam data;
• and
• back-projecting the processed cone beam data for reconstructing the 3D image dataset.