High spatial resolution X-ray computed tomography (CT) method and system

An X-ray computed tomography (CT) system comprising:

• a support structure including a gantry mounted to rotate about an axis of rotation;
• a first assembly including an X-ray source mounted on the gantry to rotate therewith for generating a cone X-ray beam;
• a second assembly including an X-ray detector mounted on the gantry to rotate therewith, wherein the detector is spaced from the source on the gantry for enabling a human or other animal body part to be interposed therebetween, the detector generating a two-dimensional electronic representation of an area of the detector on which an X-ray beam impinges at each of a plurality of rotational angles about the axis of rotation during scanning;
• means for measuring a position of the body part at each of the plurality of rotational angles, and
• a data processor for correcting for variation in the position of the body part during scanning between at least two of the plurality of rotational angles, the data processor creating an image of the body part based upon the two-dimensional electronic representations and based upon the correction for variation in the position of the body part between the at least two of the plurality of rotational angles.

An X-ray computed tomography (CT) system comprising:

• a support structure including a gantry mounted to rotate about a vertical axis of rotation;
• a first assembly including an X-ray source mounted on the gantry to rotate therewith for generating a cone X-ray beam, the first assembly further including a shadow mask for spatially modulating the source during scanning;
• a second assembly including a planar X-ray detector mounted on the gantry to rotate therewith wherein the detector is spaced from the source on the gantry for enabling a human or other animal body part to be interposed therebetween so as to be scanned by the X-ray beam to obtain a CT scan and generating output data representative thereof, the output data including a plurality of two-dimensional electronic representations of an area of the detector on which an X-ray beam impinges;
• and
• a data processor for processing the output data to obtain an image of the body part, the data processor programmed to estimate residual scatter during scanning based upon the spatial modulation by the shadow mask.

A method for imaging a body part including the steps of:

• a) generating a cone x-ray beam having a focal spot;
• b) directing at least a portion of the cone x-ray beam generally toward a body part from each of a plurality of positions rotationally spaced about an axis;
• c) during said step b), moving the focal spot through a plurality of planes, wherein the plurality of planes are generally perpendicular to the axis;
• and
• d) for each of the plurality of positions, storing a two-dimensional representation of the at least a portion of the cone x-ray beam after passing through the body part.

An X-ray computed tomography (CT) system comprising:

• a support structure including a gantry mounted to rotate about an axis of rotation during scanning;
• a first assembly including an X-ray source mounted on the gantry to rotate therewith for generating a cone X-ray beam, the first assembly including a source collimator mounted adjacent the X-ray source, wherein the X-ray source is mounted to move a focal spot through a plurality of planes during scanning, wherein the plurality of planes are perpendicular to the axis of rotation;
• a second assembly including a planar X-ray detector mounted on the gantry to rotate therewith wherein the detector is spaced from the source on the gantry for enabling a human or other animal body part to be interposed therebetween so as to generate output data comprising a plurality of two-dimensional electronic representations of an area of the detector on which an X-ray beam impinges during scanning;
• a device for offsetting the detector in a direction substantially perpendicular to the axis of rotation relative to the gantry, in order to offset the amount of alignment of the detector relative to the X-ray source and the axis of rotation;
• an arm coupled to the detector and the source collimator for changing position of the source collimator relative to the source based on position of the detector;
• and
• and a data processor for processing the output data to obtain a CT image of the body part.

A method for imaging a body part including the steps of:

• a) rotating an X-ray source about an axis and about a body part;
• b) generating a two-dimensional electronic representation of an area of the detector on which an X-ray beam impinges at each of a plurality of rotational angles about the axis of rotation during said step of rotating;
• c) determining a position of the body part at each of the plurality of rotational angles;
• and
• d) correcting for variation in the positions of the body part between at least two of the plurality of rotational angles;
• e) creating an image of the body part based upon the two-dimensional electronic representations and based upon the correction for variation in the position of the body part between the at least two of the plurality of rotational angles.