Systems and methods for image reconstruction

A method for image reconstruction, implemented on a computing device having at least one processor and at least one storage device, the method comprising:

• obtaining raw positron emission tomography (PET) data of a target object;
• determining a motion signal of the target object based on the raw PET data of the target object;
• extracting, based on the motion signal, target PET data from the raw PET data, the target PET data corresponding to a target motion signal, in the motion signal, in which motion change of the target object meets a predetermined change condition;
• and
• generating a reconstructed image of the target object by reconstructing the target PET data.

A system for image reconstruction, comprising:

• at least one storage device storing executable instructions;
• and
• at least one processor in communication with the at least one storage device, wherein when executing the executable instructions, the at least one processor is configured to cause the system to perform operations including:
• obtaining raw positron emission tomography (PET) data of a target object;
• determining a respiratory motion signal of the target object based on the raw PET data of the target object;
• correcting the respiratory motion signal based on a correction factor, wherein the correction factor is determined based on sample respiratory motion signals obtained using two different manners;
• and
• generating a reconstructed image of the target object based on the corrected respiratory motion signal and the raw PET data.