US 12,299,780 B2
Methods and systems for reconstructing a positron emission tomography image
Peng Peng, Vernon Hills, IL (US); Yi Qiang, Vernon Hills, IL (US); Wenyuan Qi, Vernon Hills, IL (US); Xiaoli Li, Vernon Hills, IL (US); and Li Yang, Vernon Hills, IL (US)
Assigned to CANON MEDICAL SYSTEMS CORPORATION, Otawara (JP)
Filed by CANON MEDICAL SYSTEMS CORPORATION, Otawara (JP)
Filed on Apr. 22, 2021, as Appl. No. 17/237,975.
Prior Publication US 2022/0343566 A1, Oct. 27, 2022
Int. Cl. G06T 7/00 (2017.01); A61B 6/03 (2006.01); G06T 11/00 (2006.01)
CPC G06T 11/006 (2013.01) [G06T 7/0012 (2013.01); A61B 6/037 (2013.01); G06T 2207/10081 (2013.01); G06T 2207/10104 (2013.01)] 4 Claims
OG exemplary drawing
 
1. An apparatus for reconstructing a positron emission tomography image, comprising:
processing circuitry configured to
extract, from raw data obtained from a positron emission tomography scanner, energy data and timing data associated with a plurality of annihilation events, the extracted energy data and the extracted timing data for each annihilation event corresponding to interactions between each of a pair of gamma rays generated by each annihilation event and one or more gamma ray detectors of the positron emission tomography scanner,
classify each annihilation event based on respective extracted energy data and respective extracted timing data,
calculate a timing resolution for each annihilation event based on the classification,
determine, for each annihilation event and based on the calculated timing resolution of the annihilation event, a width of a time-of-flight kernel, and
reconstruct, by processing circuitry, the positron emission tomography image based on the obtained raw data from the positron emission tomography scanner and the determined width of the time-of-flight kernel associated with each annihilation event,
wherein the processing circuitry is further configured to classify each annihilation event by determining, from the respective extracted energy data and the respective extracted timing data, a quantity of the one or more gamma ray detectors impacted by each of the pair of gamma rays generated by the annihilation event,
wherein the processing circuitry is further configured to classify the annihilation event as a single-crystal event, a multi-crystal event, or a hybrid-crystal event based on the determined quantity of the one or more gamma ray detectors impacted by each gamma ray of the pair of gamma rays generated by the annihilation event,
wherein the single-crystal event is a photoelectric event, the multi-crystal event is a scattering event, and the hybrid-crystal event is a combination thereof, and
wherein the processing circuitry is further configured to. when the classification indicates an annihilation event is a hybrid-crystal event, calculate the timing resolution by a convolution of a timing resolution associated with a single-crystal event and a timing resolution associated with a multi-crystal event.