Patent ID: 7324623

Claim:
A computed tomography imaging system including: a rotating gantry that rotates about an examination region along a longitudinal axis; a first radiation source disposed on the rotating gantry and arranged to emit first radiation into the examination region; a second radiation source disposed on the rotating gantry and arranged to emit second radiation into the examination region, the second radiation source being angularly spaced around the gantry from the first radiation source; a first asymmetrically adjustable collimator that is asymmetrically adjustable in a direction generally perpendicular to the longitudinal axis to position a first outer x-ray projection of the first radiation relative to a second outer x-ray projection of the first radiation; a second asymmetrically adjustable collimator that is asymmetrically adjustable in a direction generally perpendicular to the longitudinal axis to position a first outer x-ray projection of the second radiation relative to a second outer x-ray projection of the second radiation; a first radiation detector arranged to receive the first radiation, a center of the first radiation detector being angularly spaced around the gantry from the first radiation source by less than 180°; a second radiation detector arranged to receive the second radiation, a center of the second radiation detector being angularly spaced around the gantry from the second radiation source by less than 180°; and a reconstruction processor that reconstructs projection data acquired during gantry rotation by the first and second radiation detectors into one or more image representations; wherein the first asymmetrically adjustable collimator has a fixed collimation edge that defines the second outer x-ray projection of the first radiation and an adjustable collimation edge that defines the first outer x-ray projection of the first radiation, the second asymmetrically adjustable collimator has a fixed collimation edge that defines the second outer x-ray projection of the second radiation and an adjustable collimation edge that defines the first outer x-ray projection of the second radiation, and each of the adjustable collimation edges moves between a first position at which the first and second radiation is symmetrical about the rotational center and at least one other position at which the first and second radiation is asymmetrical about the rotational center.