Methods and systems for medical imaging

A system for positron emission tomography (PET) imaging, comprising:

• at least one storage device storing a set of instructions;
• and
• at least one processor in communicate with the storage device, wherein when executing the set of instructions, the at least one processor is configured to cause the system to perform operations including:
• obtaining radiation events;
• determining first response information based on the radiation events, the first response information including first time information of the radiation events;
• determining second response information based on the radiation events, the second response information including response information corresponding to a defective detector and lacking time information;
• and
• generating an image based on the first response information and the second response information.

A method for positron emission tomography (PET) imaging, comprising:

• obtaining raw data of an object, the raw data being obtained by detecting gamma photons by a plurality of detection units of a PET detector and the plurality of detection units including at least one anomaly detection unit;
• determining a count of first coincidence events on a line of response corresponding to the at least one anomaly detection unit according to the raw data;
• determining Time of Flight information related to the line of response corresponding to the at least one anomaly detection unit according to the raw data;
• determining a first Time of Flight value of each of the first coincidence events on the line of response corresponding to the at least one anomaly detection unit according to the Time of Flight information;
• and
• generating a PET image of the object according to the raw data and the first Time of Flight value of the each first coincidence event.