Methods and apparatus for scatter correction

A method for reconstructing an image of an object;

• said method comprising:
• scanning the object with a computed tomography (CT) system to obtain data;
• estimating a size of the object using the obtained data;
• using the estimated size of the object to perform scatter correction on the obtained data;
• and
• reconstructing an image using the scatter corrected data wherein said using comprises deriving a polynomial relationship between the estimated size and an estimated detector scatter profile to obtain a scaling factor, wherein said using further comprises using the obtained scaling factor to scale the estimated detector scatter profile, wherein the estimated detector scatter profile is a square root of the obtained data after a removal of a dark current from the obtained data and a channel to channel detector gain differences normalization is performed on the obtained data.

A method for reconstructing an image of an object;

• said method comprising:
• scanning the object with a computed tomography (CT) system to obtain data;
• estimating a size of the object using the obtained data;
• using the estimated size of the object to perform scatter correction on the obtained data;
• reconstructing an image using the scatter corrected data wherein said using comprises deriving a polynomial relationship between the estimated size and an estimated detector scatter profile to obtain a scaling factor;
• removing channel to channel detector gain differences from the obtained data prior to performing said step of using;
• and
• re-introducing the channel to channel detector gain differences to the scatter corrected data.

A cone beam computed tomography (CT) system comprising:

• a radiation source configured to emit a cone beam of radiation;
• a detector positioned to receive the cone beam;
• and
• a computer coupled to said source and detector said computer configured to:
• receive data from said detector;
• estimate a size of an object using the received data;
• perform scatter correction on the received data using the estimated size of the object;
• reconstruct an image using the scatter corrected data;
• derive a polynomial relationship between the estimated size and an estimated detector scatter profile to obtain a scaling factor;
• and
• use the obtained scaling factor to scale the estimated detector scatter profile, wherein the estimated detector scatter profile is a square root of the obtained data after a removal of a dark current from the obtained data and a channel to channel detector gain differences normalization is performed on the obtained data.

A computer readable medium embedded with a program configured to instruct a computer to:

• receive data from a detector;
• estimate a size of an object using the received data;
• perform scatter correction on the received data using the estimated size of the object;
• derive a polynomial relationship between the estimated size and an estimated detector scatter profile to obtain a scaling factor;
• and
• use the obtained scaling factor to scale the estimated detector scatter profile, wherein the estimated detector scatter profile is a square root of the obtained data after a removal of a dark current from the obtained data and a channel to channel detector gain differences normalization is performed on the obtained data.