Systems and methods for reconstructing cardiac images

A method implemented on at least one machine each of which has at least one processor and at least one storage device for reconstructing one or more target cardiac images, each image of the one or more target cardiac images including a plurality of elements, each element of the plurality of elements being a pixel or voxel, the method comprising:

• obtaining a plurality of projection data in a plurality of cardiac cycles generated by an imaging device, the plurality of projection data including a plurality of sub-sets of projection data, each sub-set of projection data corresponding to a cardiac motion phase of a cardiac cycle;
• determining a mean phase for the plurality of projection data;
• and
• for each of the plurality of cardiac cycles,
• selecting one or more cardiac motion phases in a preset phase range in the each cardiac cycle of the plurality of cardiac cycles, the preset range including the mean phase;
• reconstructing one or more cardiac images of the one or more cardiac motion phases based on one or more sub-sets of projection data corresponding to the one or more cardiac motion phases in the each cardiac cycle;
• determining a phase of interest in the each cardiac cycle based on the one or more cardiac images of the each cardiac cycle;
• and
• obtaining a target cardiac image of the phase of interest in the each cardiac cycle.

A method implemented on at least one machine each of which has at least one processor and at least one storage device for reconstructing one or more target cardiac images, each image of the one or more target cardiac images including a plurality of elements, each element of the plurality of elements being a pixel or voxel, the method comprising:

• obtaining a plurality of projection data in a plurality of cardiac cycles generated by an imaging device, the plurality of projection data including a plurality of sub-sets of projection data, each sub-set of projection data corresponding to a cardiac motion phase of a cardiac cycle;
• reconstructing a first cardiac image of a first phase of interest in a first cardiac cycle of the plurality of cardiac cycles;
• and
• reconstructing a second cardiac image of a second phase of interest in a second cardiac cycle of the plurality of cardiac cycles;
• wherein
• the second phase of interest is different from the first phase of interest;
• and
• at least one of the first phase of interest or the second phase of interest is determined according to a process including:
• determining a mean phase for the plurality of projection data;
• and
• in each of the at least one of the first cardiac motion phase or the second cardiac motion phase,
• selecting one or more cardiac motion phases in a preset phase range in the each cardiac cycle, the preset range including the mean phase;
• reconstructing one or more cardiac images of the one or more cardiac motion phases based on one or more sub-sets of projection data corresponding to the one or more cardiac motion phases in the each cardiac cycle;
• and
• determining a phase of interest in the each cardiac cycle based on the one or more cardiac images of the each cardiac cycle.