CN-121987973-A - Image reconstruction method, image reconstruction device, electronic device, storage medium, and program product

CN121987973ACN 121987973 ACN121987973 ACN 121987973ACN-121987973-A

Abstract

The application relates to the technical field of imaging, and particularly discloses an image reconstruction method, an image reconstruction device, electronic equipment, a storage medium and a program product. The method comprises the steps of continuously detecting positrons generated by proton induction in a proton beam delivery period, determining a plurality of single events by controlling detection equipment, partitioning the proton beam delivery period according to the counting rate of the single events at different moments, performing coincidence operation on the plurality of single events to determine each coincidence event, and respectively reconstructing images of a set of the coincidence events in each target interval based on the partitioning result of the proton beam delivery period, wherein each target interval corresponds to a single energy layer. The method solves the problem that the accurate extraction of the single-field or single-energy-layer dosage information cannot be realized due to the overlapping of PET signals caused by the multi-field delivery mode or the multi-energy-layer delivery mode.

Inventors

LI XIMENG
QIU AO
LIU QIBIN
LIU ZIXIAO
HU WENTAO
WAN LIN
XIE QINGGUO

Assignees

苏州瑞派宁科技有限公司

Dates

Publication Date: 20260508
Application Date: 20251231

Claims (20)

1. An image reconstruction method, characterized in that the image reconstruction method comprises: In the proton beam delivery period, controlling the detection equipment to continuously detect positrons generated by proton induction so as to determine a plurality of single events; partitioning the proton beam delivery period according to the counting rate of the single event at different moments; Carrying out coincidence operation on a plurality of single events to determine each coincidence event; And respectively carrying out image reconstruction on the set of the coincidence events in each target interval based on the partitioning result of the proton beam delivery period, wherein a single target interval corresponds to a single energy layer.
2. The image reconstruction method according to claim 1, wherein the partitioning the proton beam delivery period according to the count rate of the single event at different times comprises: Determining each moment when the counting rate of the single event exceeds a preset threshold value to form a first moment set; Dividing the proton beam delivery period into a background interval, a beam-in interval and a beam-out interval in sequence according to the earliest time and the latest time in the first time set; And respectively determining the intervals which are alternately arranged in the beam intervals as a first counting rate interval and a second counting rate interval, wherein the counting rate of single events in the first counting rate interval is higher than that of single events in the second counting rate interval.
3. The image reconstruction method according to claim 1, wherein the event data of each single event includes at least time data, position data and energy data, and wherein the performing coincidence operation on the plurality of single events to determine each coincidence event includes: screening a plurality of single events based on the energy data of each single event to obtain a single event set; And carrying out time coincidence operation and position coincidence operation on each single event in the single event set based on the time data and the position data of each single event in the single event set so as to determine a plurality of coincidence events.
4. The image reconstruction method according to claim 3, wherein the filtering the plurality of single events based on the energy data of each single event to obtain a single event set includes: Setting energy window conditions; And screening out all the single events with energy data meeting the energy window condition from a plurality of single events to form a single event set.
5. The image reconstruction method according to claim 3, wherein said performing a time coincidence operation on each of the single events in the single event set based on time data of each of the single events in the single event set to determine a plurality of coincidence events includes: setting a time window condition; And carrying out time coincidence processing on two single events meeting the time window condition in the single event set to determine a plurality of coincidence events.
6. The image reconstruction method according to claim 2, wherein the target interval is the first count rate interval.
7. The image reconstruction method according to claim 6, wherein the separately reconstructing the set of coincidence events in each target interval based on the partition result of the proton beam delivery period includes: For each first counting rate interval, respectively acquiring a set of coincidence events in the first counting rate interval, and reconstructing an image; And determining the reconstructed image as an image of the energy layer corresponding to the first counting rate interval.
8. The image reconstruction method according to claim 6, wherein the separately reconstructing the set of coincidence events in each target interval based on the partition result of the proton beam delivery period includes: For each first counting rate interval, acquiring a set of coincidence events from the starting time of the background interval to the ending time of the first counting rate interval, and performing image reconstruction to obtain an accumulated image; Performing differential operation on the accumulated image corresponding to the ith first counting rate interval and the accumulated image corresponding to the ith-1 first counting rate interval aiming at the ith first counting rate interval to obtain an image of an energy layer corresponding to the ith first counting rate interval; Wherein i is more than or equal to 1 and less than or equal to n, i is a positive integer, and n is the number of the first counting rate intervals.
9. The method of image reconstruction according to claim 1, wherein controlling the detection device to continuously detect positrons induced by protons during the proton beam delivery period comprises acquiring detection data using a memory pool algorithm.
10. The image reconstruction method according to claim 1, wherein the detection device comprises a positron emission tomography detector.
11. An image reconstruction apparatus, characterized in that the image reconstruction apparatus comprises: The detection module is used for controlling the detection equipment to continuously detect positrons generated by proton induction in the proton beam delivery period so as to determine a plurality of single events; the partitioning module is used for partitioning the proton beam delivery period according to the counting rate of the single event at different moments; the coincidence module is used for carrying out coincidence operation on a plurality of single events so as to determine each coincidence event; And the reconstruction module is used for respectively reconstructing images of the set of the coincidence events in each target interval based on the partition result of the proton beam delivery period, and the single target interval corresponds to the single energy layer.
12. The image reconstruction apparatus according to claim 11, wherein the partitioning module comprises: The first determining unit is used for determining each moment when the counting rate of the single event exceeds a preset threshold value to form a first moment set; the dividing unit is used for dividing the proton beam delivery period into a background interval, a beam-in interval and a beam-out interval in sequence according to the earliest time and the latest time in the first time set; And the second determining unit is used for determining the intervals alternately arranged in the beam intervals as a first counting rate interval and a second counting rate interval respectively, wherein the counting rate of single events in the first counting rate interval is higher than that of single events in the second counting rate interval.
13. The image reconstruction apparatus according to claim 11, wherein the conforming module comprises: The screening unit is used for screening a plurality of single events based on the energy data of each single event to obtain a single event set; The coincidence unit is used for carrying out time coincidence operation and position coincidence operation on each single event in the single event set based on the time data and the position data of each single event in the single event set so as to determine a plurality of coincidence events.
14. The image reconstruction apparatus according to claim 13, wherein the screening unit is further configured to: Setting energy window conditions; And screening out all the single events with energy data meeting the energy window condition from a plurality of single events to form a single event set.
15. The image reconstruction apparatus according to claim 13, wherein the conforming unit is further configured to: setting a time window condition; And carrying out time coincidence processing on two single events meeting the time window condition in the single event set to determine a plurality of coincidence events.
16. The image reconstruction apparatus according to claim 12, wherein the target interval is the first count rate interval.
17. The image reconstruction apparatus according to claim 16, wherein the reconstruction module comprises: The first reconstruction unit is used for respectively acquiring a set of coincidence events in each first counting rate interval and reconstructing an image; And a third determining unit, configured to determine the reconstructed image as an image of the energy layer corresponding to the first count rate interval.
18. The image reconstruction apparatus according to claim 16, wherein the reconstruction module comprises: The second reconstruction unit is used for acquiring a set of coincidence events from the starting time of the background interval to the ending time of the first counting rate interval for each first counting rate interval, and performing image reconstruction to obtain an accumulated image; The computing unit is used for carrying out differential computation on the accumulated image corresponding to the ith first counting rate interval and the accumulated image corresponding to the ith-1 first counting rate interval aiming at the ith first counting rate interval to obtain an image of an energy layer corresponding to the ith first counting rate interval; Wherein i is more than or equal to 1 and less than or equal to n, i is a positive integer, and n is the number of the first counting rate intervals.
19. An electronic device comprising an image reconstruction apparatus as claimed in any one of claims 11 to 18.
20. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the computer program implementing the steps of the image reconstruction method as claimed in any one of claims 1 to 10 when executed by the processor.

Description

Image reconstruction method, image reconstruction device, electronic device, storage medium, and program product Technical Field The present application relates to the field of imaging technologies, and in particular, to an image reconstruction method, an image reconstruction device, an electronic device, a storage medium, and a program product. Background Proton Therapy (PT) is mainly to precisely irradiate a tumor with a Proton beam to achieve maximum tumor ablation and minimum normal tissue damage. The main advantage of the method is that the method has a unique Bragg peak effect, namely, protons release most of energy at a specific depth and then decay rapidly, and the maximum energy of rays is accurately adjusted to a focus part during treatment, so that concentrated irradiation on the focus part can be realized, and excessive damage to normal cells can not be caused. Thanks to this advantage, proton therapy is recognized as a key means for realizing accurate medicine in the field of radiotherapy, and has become an important development field at home and abroad. PET (Positron Emission Tomography ) is capable of dynamically capturing transient positron species (such as 15O、11 C) generated by the interaction of a proton beam with tissue, thereby providing three-dimensional information with high spatial-temporal resolution for range verification. However, in clinic, the delivery mode of multiple fields (i.e. tumor is irradiated from different angles by multiple proton beams, improving the dose distribution conformality) and the delivery mode of multiple energy layers (Multi-ENERGY LAYER) (i.e. proton beams of different energies are delivered in layers within the same field, covering different depths of tumor) cause serious overlapping phenomenon of PET signals, while cross irradiation of multiple fields further aggravates aliasing condition of signals, which makes it difficult to distinguish the contributions of each component by the conventional image reconstruction algorithm. This limitation prevents accurate extraction of single field or single energy layer dose information. Disclosure of Invention In view of the foregoing, it is desirable to provide an image reconstruction method, an image reconstruction apparatus, an electronic device, a computer-readable storage medium, and a computer program product. According to a first aspect of an embodiment of the present application, there is provided an image reconstruction method including: In the proton beam delivery period, controlling the detection equipment to continuously detect positrons generated by proton induction so as to determine a plurality of single events; partitioning the proton beam delivery period according to the counting rate of the single event at different moments; Carrying out coincidence operation on a plurality of single events to determine each coincidence event; And respectively carrying out image reconstruction on the set of the coincidence events in each target interval based on the partitioning result of the proton beam delivery period, wherein a single target interval corresponds to a single energy layer. In one embodiment, the partitioning the proton beam delivery period according to the count rates of the single events at different moments includes: Determining each moment when the counting rate of the single event exceeds a preset threshold value to form a first moment set; Dividing the proton beam delivery period into a background interval, a beam-in interval and a beam-out interval in sequence according to the earliest time and the latest time in the first time set; And respectively determining the intervals which are alternately arranged in the beam intervals as a first counting rate interval and a second counting rate interval, wherein the counting rate of single events in the first counting rate interval is higher than that of single events in the second counting rate interval. In one embodiment, the event data of each single event at least comprises time data, position data and energy data, and the coincidence operation on the plurality of single events to determine each coincidence event comprises: screening a plurality of single events based on the energy data of each single event to obtain a single event set; And carrying out time coincidence operation and position coincidence operation on each single event in the single event set based on the time data and the position data of each single event in the single event set so as to determine a plurality of coincidence events. In one embodiment, the screening the plurality of single events to obtain the single event set based on the energy data of each single event includes: Setting energy window conditions; And screening out all the single events with energy data meeting the energy window condition from a plurality of single events to form a single event set. In one embodiment, the performing, based on the time data of each single event in the single event set, a time c