CN111493915B - Time correction method for PET - Google Patents
Time correction method for PET Download PDFInfo
- Publication number
- CN111493915B CN111493915B CN202010310833.3A CN202010310833A CN111493915B CN 111493915 B CN111493915 B CN 111493915B CN 202010310833 A CN202010310833 A CN 202010310833A CN 111493915 B CN111493915 B CN 111493915B
- Authority
- CN
- China
- Prior art keywords
- time correction
- time
- correction table
- module
- pet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000012937 correction Methods 0.000 title claims abstract description 83
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000009826 distribution Methods 0.000 claims description 21
- 238000005259 measurement Methods 0.000 claims description 3
- 230000002194 synthesizing effect Effects 0.000 claims description 3
- 238000013170 computed tomography imaging Methods 0.000 abstract description 2
- 238000002600 positron emission tomography Methods 0.000 description 21
- 239000013078 crystal Substances 0.000 description 8
- 238000001228 spectrum Methods 0.000 description 8
- 230000002285 radioactive effect Effects 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 230000004044 response Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000002123 temporal effect Effects 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 238000003384 imaging method Methods 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000009206 nuclear medicine Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000000700 radioactive tracer Substances 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
- A61B6/03—Computed tomography [CT]
- A61B6/037—Emission tomography
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
- A61B6/5258—Devices using data or image processing specially adapted for radiation diagnosis involving detection or reduction of artifacts or noise
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
- A61B6/58—Testing, adjusting or calibrating thereof
- A61B6/582—Calibration
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Medical Informatics (AREA)
- Radiology & Medical Imaging (AREA)
- Molecular Biology (AREA)
- Biophysics (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Optics & Photonics (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- High Energy & Nuclear Physics (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Nuclear Medicine (AREA)
- Measurement Of Radiation (AREA)
Abstract
The invention provides a time correction method for PET, which relates to the technical field of X-ray computed tomography imaging, and uses a column source, wherein the size of the column source corresponds to an FOV (field of view) and can cover two or more minimum time reading units. On the basis, the time deviation among the pixels is calculated again to obtain the total time correction table. The time correction method of the present invention does not require column source sizes to be too large and can reduce scattering problems caused by too large a source size. Meanwhile, when time deviation exists between detectors or electronics, the method is used as well, all LORs of the whole ring can be corrected, the calculation efficiency is higher, iteration convergence is faster, and the obtained time precision is higher.
Description
Technical Field
The invention relates to a time correction method for PET, belonging to the technical field of X-ray computed tomography imaging.
Background
A Positron Emission Tomography (PET) imaging system is a nuclear medicine imaging device, which is mainly composed of a detector system, an electronics system, a data acquisition system and a reconstruction system. The detector system comprises crystal (BGO, LYSO, etc.), photoelectric conversion device (PMT, SiPM, etc.) and front-end electronics. PET achieves tomographic imaging by acquiring a pair of gamma photons generated by a radiotracer injected into a living body. For a PET system, there are many parameters that affect its performance, and temporal resolution is one of the important influencing parameters.
Generally speaking, the time resolution of the system has a large influence on the count rate of random events, which may increase the noise floor during the image reconstruction process and determine the final image quality. The random event count rate can be represented by equation (1):
NR＝2τN1N2 (1)
wherein N is1And N2Respectively, representing the count rate of gamma rays detected by each of a pair of detectors, and 2 tau representing the time window of the coincidence event, the size of the time window being dependent on the time resolution of the system. Thus improving the time resolution of the system may beThe number of random events is effectively reduced, thereby improving the image quality.
The time resolution of the system is usually represented by the full width at half maximum of a statistical graph (time spectrum) of the time difference of all coincidence events acquired by a radioactive source (point source or line source) placed in the center of the FOV, and ideally, the statistical time spectrum should conform to a strict narrow gaussian distribution, and the gaussian peak is located at a position where the time difference is equal to 0, however, in actual cases, the statistical graph has a certain offset and spread, which results in the reduction of the time resolution of the system.
The reasons for the deterioration of the temporal performance of the PET system can be summarized as follows:
(1) differences in physical properties between crystals. For a PET system, although the same crystal is used, due to the difference between the physical properties of the crystal itself, the time response of different crystals to incident gamma rays is different, such as crystal scintillation, photon propagation in the crystal, etc.;
(2) differences in electronic systems. Due to differences in manufacturing processes and the like, the signal transmission speed, amplification factor, response time, delay time and the like of an electronic system connected with different crystals are different, and the aging degree, voltage, threshold value and the like of electronics also cause the difference in response time; in addition, there may be a large time deviation between the detectors due to cables (e.g., synchronous clock lines, etc.).
(3) External environmental factors. Variations in the external environment, such as temperature, humidity, etc., can also lead to different electronic delays.
For PET systems, up to tens of thousands of signal channels, each signal channel (pixel) is required to be time aligned in order to improve the time resolution of the overall system. Currently, coincidence data is acquired mainly using radioactive sources (column sources or shell sources such as Na-22, Ge-68, FDG-18, etc.) placed in the center of the FOV, and the time deviation of each pixel is obtained by decoding the time spectrum of the pixel to other pixels in the coincidence data and calculating the mean of the time spectra. However, the time correction table obtained by the method can only correct the LOR within the FOV covered by the radioactive source accurately, and cannot achieve a good correction effect on the LOR outside the FOV. Thus, using this approach, the source size tends to be larger to cover more of the FOV. However, the larger size causes increased scattering events in coincidence events, resulting in less accurate time corrections. Moreover, this method is premised on that the time deviation of all pixels of the whole ring is random (uniformly distributed), and when there is time deviation among modules of the detector, the time spectrum of a single pixel may have multiple peaks, so that the time deviation value cannot be accurately obtained.
In summary, the prior art uses column source or shell source (Na-22, Ge-68, FDG-18, etc.) to obtain coincidence data, and obtains the time deviation by counting the time distribution of coincidence events corresponding to each pixel, and mainly has the following defects:
1. the requirement for the size of the radioactive source is high, and the size of the radioactive source can cover a large FOV (such as being larger than a clinically-used FOV550 mm);
2. when the size of the radioactive source is large, scattering is serious, and the correction effect is poor;
3. the LOR correction effect of the radioactive source covering outside the FOV is not ideal;
4. when there is a large time deviation between detectors or electronics, the correct time deviation value for each pixel cannot be obtained.
The present application was made based on this.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides a time correction method for PET, which does not need a column source with a large size, is suitable for the situation that time deviation exists between detectors or electronics, and has the advantages of higher calculation efficiency, quicker iterative convergence and higher obtained time precision.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a time correction method for PET, comprising the steps of:
step one, a column source is arranged in the center of an FOV, and reasonable measurement parameters are set;
step two, collecting a conforming data packet;
step three, analyzing coincidence numberAccording to the packet, counting each detector module MαWith its face-to-face module
And counting the detector modules MαNext adjacent module Mα+1With each detector module MαFace to face module
Calculating to obtain a time correction table of each module, which is a first-stage time correction table; wherein n represents: assume that a PET system has n detector modules;
step four, using the first-stage time correction table to carry out module-stage correction on the original coincidence data, counting the time difference distribution of all coincidence events corresponding to each pixel, and calculating to obtain each pixel time correction table which is a second-stage time correction table;
step five, synthesizing the first and second time correction tables to obtain a total time correction table which is a third time correction table;
and step six, correcting the original time information of the conforming data by using a third-stage time correction table, repeating the step three to the step five, and iterating for k times until an iteration termination rule is met, so as to obtain a more accurate time correction table which is a final time correction table and is stored.
Further, the column source in step one is Na-22, Ge-68 or FDG-18, and the column source size corresponding to the minimum FOV only needs to cover the two opposite modules.
Further, the parameters measured in the first step include FOV and time window.
Further, in the third step, the time deviation of every two adjacent modules is obtained from the average value difference of the two distributions by calculating the average value of each distribution, and further the time correction table of each module is obtained.
Further, in the fourth step, the time correction value of each pixel is found by calculating the average value of each distribution, and the time correction table of each pixel is further obtained.
The principle and the beneficial technical effects of the invention are as follows: the invention uses column source (Na-22, Ge-68, FDG-18, etc.), the column source size (such as diameter 30mm) corresponds to FOV and can cover two or more minimum time reading units (such as the module in the invention), firstly, the time deviation between each detector module is calculated by using the coincidence data, the time correction table is obtained, and the time correction table is substituted into the original data to correct the time information. On the basis, the time deviation among the pixels is calculated again to obtain the total time correction table. This approach does not require the column source to be too large in size and can reduce scattering problems due to too large a source size. Meanwhile, when time deviation exists between detectors or electronics, the method is also applicable, all LORs of the whole ring can be corrected, the calculation efficiency is higher, the iterative convergence is faster, and the obtained time precision is higher.
Drawings
FIG. 1 is a schematic diagram of the PET ring module level time calibration of the present embodiment;
FIG. 2 is a schematic diagram of the PET ring pixel level time correction of the present embodiment;
fig. 3 is a schematic diagram of a time correction process in this embodiment.
Detailed Description
In order to make the technical means of the present invention and the technical effects achieved thereby clearer and more complete, an embodiment is provided, and the method provided by the present embodiment is applicable to all PET systems, and is described in detail below with reference to the accompanying drawings:
fig. 3 is a schematic diagram of a time correction process in this embodiment, starting from data acquisition of the PET system, the time correction implementation process in this embodiment is as follows:
step one, after the PET system is started up stably, a column source is placed in the center of an FOV, and reasonable parameters such as the FOV and a time window are set:
the present embodiment is characterized in that a column source (Na-22, Ge-68, FDG-18, etc.) arranged in the center of the FOV is used for acquiring the coincidence data, and the column source size corresponds to the FOV and only needs to cover more than two opposite modules.
Step two, begin to gather and accord with the data, gather for enough long time, guarantee that the time spectrum of each pixel of the detector array has sufficient statistics to count:
coincidence event line of response (LOR) data packets between detectors of the entire PET system are obtained over a period of time.
Step three, analyzing the coincidence data packet, and counting each detector module MαAnd its next adjacent module Mα+1With its face-to-face module
And calculating the mean value of each distribution, obtaining the time deviation of two adjacent modules from the mean value difference of the two distributions, and obtaining the time correction table (first-stage time correction table) of each module from the time deviation of two adjacent modules, which can refer to fig. 1:
suppose a PET system has n detector modules (M)0～Mn-1) And the detector module is assumed to be the minimum time readout unit. As shown in FIG. 1, first, M is counted0With its face-to-face module
The time difference distribution of all coincidence events between them, the mean value of the distribution is the time deviation between the two modules
Recalculate and M0Next module M in the neighborhood1And
the time difference distribution of all coincidence events between them, the mean value of the distribution is the time deviation between the two modules
The module M can be obtained through the time deviation of the two modules1And M0The time offset between is:
M0defining the time deviation as 0 for the start module, then M1Time correction value C of module1＝-T1,0. In the same way, by module M1And
time deviation therebetween
Module M2And
time deviation therebetween
A module M can be obtained2And M1Time deviation T between2,1Then module M2Time correction value C of2＝C1-T2,1. By analogy, any module M on the ring can be obtainedαThe time correction value of (a) is:
the time correction values of all modules on the ring form a first stage time correction table.
Step four, using the first-stage time correction table to perform module-stage correction on the original coincidence data, using the corrected result to count the time difference distribution of all coincidence events corresponding to each pixel, calculating the mean value of each distribution, finding the time correction value of each pixel, and obtaining an intermediate correction table (second-stage time correction table), which can refer to fig. 2:
as described above, after the time offset between the detector modules on the PET ring is calculated in sequence, the time references of all the detector modules are aligned to 0, and if there is a smaller time readout unit in the detector, the time offset between the units should be calculated in sequence accordingly. After the time offset between the detector modules is corrected to 0, the time offset between the pixels can be considered to be random, i.e. uniformly distributed.
On the basis, the time spectrum of all coincidence events corresponding to each pixel is counted. As shown in FIG. 2, for a particular pixel A (which may be anywhere on the ring), there are a large number of pixels B within the FOVi(0. ltoreq. i.ltoreq.N) can be associated with the pixels, the LORs of the associations are counted, and the mean value of the temporal distribution of the pixel A can be represented by equation (4):
wherein, tA、
Time of true arrival of photon at detector, δA、
Is the time offset of the pixel. Since the source is centered in the FOV and the column source itself is an axisymmetric structure, the first term in equation (4)
The mean value is 0, which is a symmetrical distribution centered at 0. For a large number of pixels Bi(0. ltoreq. i.ltoreq.N), the time deviations of these pixels can be regarded statistically as a random uniform distribution, i.e., the average value is 0, i.e., the third term in equation (4) can be regarded as
Is 0. Therefore, the deviation of the mean value of the time spectrum of the specific pixel A from 0 is the time deviation delta of the pixelA。
And traversing the whole ring to obtain the time deviation of all the pixels and obtain a second-stage time correction table.
Step five, synthesizing the first and second time correction tables to obtain a total time correction table (a third time correction table): in conclusion, the loop has any pixel A (belonging to any module M)α) The total time correction is:
step six, correcting the original time information of the conforming data by using a third-stage time correction table, repeating the steps three to five, and iterating for k times until an iteration termination rule is met, so as to obtain a more accurate time correction table which is a final time correction table:
and after a third-stage time correction table is obtained, substituting the time information of the corrected original coincidence data, and continuously calculating the time deviation of each module and the time deviation of each pixel in a cross iterative manner, so that the time deviation of each pixel on the ring is more and more approximate to an ideal condition, and a more accurate result is obtained. After k iterations, the temporal correction value for pixel a is:
and seventhly, storing the time correction table to a memory, and downloading the time correction table to the PET electronic system so as to quickly inquire and correct the time output value of the corresponding detector during measurement of the PET system.
The large size of the radiation source present with prior art calibration methods requires coverage of a large FOV (e.g., greater than the clinically usual FOV550 mm); the time deviation of each pixel point is directly calculated in an iterative mode, and the convergence speed is low; only the LOR inside the FOV can be corrected, and the LOR outside the FOV is not corrected perfectly; and if the time difference between pixels in the FOV is large, the time distribution is not normally distributed (such as multi-peak), and various defects of deviation can be corrected, so that the following technical effects can be realized by the embodiment:
(1) by adopting the time correction method of the embodiment, the column source size can be covered by more than two modules corresponding to the FOV, so that the scattering case rate can be reduced;
(2) the time correction method of the embodiment firstly calculates the time deviation among the detector modules, calculates the time deviation of each pixel point on the basis, and has the advantages of cyclic iteration and high convergence rate;
(3) by adopting the time correction method of the embodiment, all response Lines (LOR) of the whole ring can be corrected;
(4) the time correction method of the present embodiment is also applicable when there is a large time deviation between detectors or electronics.
The above description is provided for the purpose of further elaboration of the technical solutions provided in connection with the preferred embodiments of the present invention, and it should not be understood that the embodiments of the present invention are limited to the above description, and it should be understood that various simple deductions or substitutions can be made by those skilled in the art without departing from the spirit of the present invention, and all such alternatives are included in the scope of the present invention.
Claims (5)
1. A method of time correction for PET comprising the steps of:
step one, a column source is arranged in the center of an FOV, and reasonable measurement parameters are set;
step two, collecting a conforming data packet;
step three, analyzing the coincidence data packet, and counting each detector module MαWith its face-to-face module
And counting the detector modules MαNext adjacent module Mα+1With each detector module MαFace to face module
Calculating to obtain a time correction table of each module, which is a first-stage time correction table; wherein n represents: assume that a PET system has n detector modules;
step four, using the first-stage time correction table to carry out module-stage correction on the original coincidence data, counting the time difference distribution of all coincidence events corresponding to each pixel, and calculating to obtain each pixel time correction table which is a second-stage time correction table;
step five, synthesizing the first and second time correction tables to obtain a total time correction table which is a third time correction table;
and step six, correcting the original time information of the conforming data by using a third-stage time correction table, repeating the step three to the step five, and iterating for k times until an iteration termination rule is met, so as to obtain a more accurate time correction table which is a final time correction table and is stored.
2. A time correction method for PET as claimed in claim 1, characterized in that: the column source in step one is Na-22, Ge-68 or FDG-18, and the column source size corresponding to the minimum FOV only needs to cover the two opposite modules.
3. A time correction method for PET as claimed in claim 1, characterized in that: the parameters measured in the first step comprise FOV and time window.
4. A time correction method for PET as claimed in claim 1, characterized in that: in the third step, the time deviation of every two adjacent modules is obtained from the average value difference of the two distributions by calculating the average value of each distribution, and further the time correction table of each module is obtained.
5. A time correction method for PET as claimed in claim 1, characterized in that: in the fourth step, the time correction value of each pixel is found by calculating the average value of each distribution, and the time correction table of each pixel is further obtained.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010310833.3A CN111493915B (en) | 2020-04-20 | 2020-04-20 | Time correction method for PET |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010310833.3A CN111493915B (en) | 2020-04-20 | 2020-04-20 | Time correction method for PET |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111493915A CN111493915A (en) | 2020-08-07 |
| CN111493915B true CN111493915B (en) | 2021-02-02 |
Family
ID=71877717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010310833.3A Active CN111493915B (en) | 2020-04-20 | 2020-04-20 | Time correction method for PET |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111493915B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112151162B (en) * | 2020-09-21 | 2022-10-21 | 明峰医疗系统股份有限公司 | PET time real-time correction and reconstruction method and system |
| CN112925007B (en) * | 2021-01-29 | 2022-11-18 | 明峰医疗系统股份有限公司 | Measuring method and system of PET detector and computer readable storage medium |
| CN112932515B (en) * | 2021-01-29 | 2022-06-21 | 明峰医疗系统股份有限公司 | Time correction method for TOF-PET |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5272344A (en) * | 1992-11-10 | 1993-12-21 | General Electric Company | Automated coincidence timing calibration for a pet scanner |
| US8796637B1 (en) * | 2013-05-24 | 2014-08-05 | Kabushiki Kaisha Toshiba | Timing calibration for time-of-flight (TOF) PET using positron-emitting isotopes and annihilation targets |
| CN104434160A (en) * | 2013-09-18 | 2015-03-25 | 上海联影医疗科技有限公司 | PET scanning device and time migration correcting method thereof |
| CN104644204A (en) * | 2015-02-09 | 2015-05-27 | 中国船舶重工集团公司第七一九研究所 | Time correcting method and system for digital PET (positron emission tomography) |
| CN104977601A (en) * | 2015-06-20 | 2015-10-14 | 明峰医疗系统股份有限公司 | Time delay measurement method for SiPM-based PET system |
| CN106344058A (en) * | 2016-08-09 | 2017-01-25 | 沈阳东软医疗系统有限公司 | Method, device and system of time correction used for PET system |
| CN107110988A (en) * | 2014-10-27 | 2017-08-29 | 皇家飞利浦有限公司 | Pet detector timing alignment |
| CN107137101A (en) * | 2017-04-24 | 2017-09-08 | 沈阳东软医疗系统有限公司 | A kind of time calibrating method and device |
| CN110749916A (en) * | 2019-10-25 | 2020-02-04 | 上海联影医疗科技有限公司 | Method and device for acquiring time delay amount of PET detector crystal and computer equipment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8779367B2 (en) * | 2012-02-20 | 2014-07-15 | General Electric Company | System and method for correcting timing errors in a medical imaging system |
-
2020
- 2020-04-20 CN CN202010310833.3A patent/CN111493915B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5272344A (en) * | 1992-11-10 | 1993-12-21 | General Electric Company | Automated coincidence timing calibration for a pet scanner |
| US8796637B1 (en) * | 2013-05-24 | 2014-08-05 | Kabushiki Kaisha Toshiba | Timing calibration for time-of-flight (TOF) PET using positron-emitting isotopes and annihilation targets |
| CN104434160A (en) * | 2013-09-18 | 2015-03-25 | 上海联影医疗科技有限公司 | PET scanning device and time migration correcting method thereof |
| CN107110988A (en) * | 2014-10-27 | 2017-08-29 | 皇家飞利浦有限公司 | Pet detector timing alignment |
| CN104644204A (en) * | 2015-02-09 | 2015-05-27 | 中国船舶重工集团公司第七一九研究所 | Time correcting method and system for digital PET (positron emission tomography) |
| CN104977601A (en) * | 2015-06-20 | 2015-10-14 | 明峰医疗系统股份有限公司 | Time delay measurement method for SiPM-based PET system |
| CN106344058A (en) * | 2016-08-09 | 2017-01-25 | 沈阳东软医疗系统有限公司 | Method, device and system of time correction used for PET system |
| CN107137101A (en) * | 2017-04-24 | 2017-09-08 | 沈阳东软医疗系统有限公司 | A kind of time calibrating method and device |
| CN110749916A (en) * | 2019-10-25 | 2020-02-04 | 上海联影医疗科技有限公司 | Method and device for acquiring time delay amount of PET detector crystal and computer equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111493915A (en) | 2020-08-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111493915B (en) | Time correction method for PET | |
| US10914851B2 (en) | Time of flight calibration in digital positron emission tomography | |
| US10634801B2 (en) | Detector in an imaging system | |
| US7129495B2 (en) | Method and apparatus for timing calibration in a PET scanner | |
| US7459688B2 (en) | Radiation detection circuit and apparatus for radiographic examination | |
| WO2017016353A1 (en) | Online real-time correction method and system for positron emission tomography detector | |
| US7405405B2 (en) | Method and system for reconstructing an image in a positron emission tomography (PET) system | |
| Nadig et al. | Evaluation of the PETsys TOFPET2 ASIC in multi-channel coincidence experiments | |
| JP6801906B2 (en) | Time compensator used in PET system | |
| CN108209958B (en) | Method for determining and acquiring normalization correction factor and medical imaging method | |
| CN107440734B (en) | PET scanning method and device | |
| CN112882085B (en) | Temperature-adaptive PET detector energy correction method and system | |
| St James et al. | Simulation study of spatial resolution and sensitivity for the tapered depth of interaction PET detectors for small animal imaging | |
| Niknejad et al. | Validation of a highly integrated SiPM readout system with a TOF-PET demonstrator | |
| CN112932515B (en) | Time correction method for TOF-PET | |
| WO2021238929A1 (en) | State detection method and system for imaging device | |
| US9274234B2 (en) | Nuclear medicine imaging apparatus and nuclear medicine imaging system | |
| CN112932517B (en) | Background radioactivity realization time self-correction method and device | |
| KR101686306B1 (en) | Signal loss detection and energy detection circuit without energy distortion method and structure from pulse pile-up at the signal readout integrated circuit in all radiation counting sensors | |
| US9285486B2 (en) | Method for radiation detection signal processing | |
| CN117442224A (en) | Method for correcting time of coincidence detection system | |
| JPH10268053A (en) | Nuclear medicine diagnosis device | |
| CN115951394A (en) | Time correction method, time correction device, electronic equipment and computer-readable storage medium | |
| CN113116371A (en) | PET device and calibration method | |
| CN116068607A (en) | Method, system, device and medium for correcting timing walk based on energy information |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |