Abstract: As an illustration of generating a motion map, although the cardiac CT is described for selecting an optimal phase, the disclosure is not limited to the cardiac CT. For the cardiac CT, the cardiac phase map is efficiently generated based upon helical scan data, and the optimal phase is selected within a reasonable time. At the same time, the optimal phase is accurately determined based upon complementary rays as indexes for minimal movement so as to select the projection data for minimizing artifacts in reconstructed cardiac images. The helically scanned data reflect motion within the same cardiac cycle or over the continuous cardiac cycles. The application of the complementary ray technique to the helically scanned data is accomplished by three-dimensionally determining a pair of the complementary rays in order to take into account motion within the same cardiac cycle or over the continuous cardiac cycles.

Abstract: A method of reconstructing a volume image of an object includes receiving circle projection data collected by a detector along a circular path with respect to the object; receiving line projection data collected by the detector along a linear path with respect to the object; producing a reconstructed circle path volume image of the object from the pre-processed circle projection data using a reconstruction algorithm that includes a ramp filter; producing a reconstructed line path volume image of the object from pre-processed line projection data using a reconstruction algorithm that includes a Hubert filter; and combining the reconstructed circle path volume image and the reconstructed line path volume image to produce the volume image of the object. An apparatus and computer program product are also described.

Abstract: As an illustration of generating a motion map, although the cardiac CT is described for selecting an optimal phase, the disclosure is not limited to the cardiac CT. For the cardiac CT, the cardiac phase map is efficiently generated based upon helical scan data, and the optimal phase is selected within a reasonable time. At the same time, the optimal phase is accurately determined based upon complementary rays as indexes for minimal movement so as to select the projection data for minimizing artifacts in reconstructed cardiac images. The helically scanned data reflect motion within the same cardiac cycle or over the continuous cardiac cycles. The application of the complementary ray technique to the helically scanned data is accomplished by three-dimensionally determining a pair of the complementary rays in order to take into account motion within the same cardiac cycle or over the continuous cardiac cycles.

Abstract: A method of reconstructing a volume image of an object includes receiving circle projection data collected by a detector along a circular path with respect to the object; receiving line projection data collected by the detector along a linear path with respect to the object; producing a reconstructed circle path volume image of the object from the pre-processed circle projection data using a reconstruction algorithm that includes a ramp filter; producing a reconstructed line path volume image of the object from pre-processed line projection data using a reconstruction algorithm that includes a Hubert filter; and combining the reconstructed circle path volume image and the reconstructed line path volume image to produce the volume image of the object. An apparatus and computer program product are also described.