206 results about "Positron" patented technology

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

A positron emission tomography (PET) scanner includes a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of scintillator detectors. Each scintillator detector comprises a monolithic scintillation crystal and a plurality of photodetector arrays, such as silicon photomultipliers (SiPMs). A photodetector array is positioned on at least two nonparallel faces of each scintillation crystal. In some examples, a photodetector array is positioned on each of three orthogonal faces of each scintillation crystal.

A system and a method for PET imaging may be provided. Scan data of an object collected by a PET scan over a scan time period may be obtained. A plurality of target sets of scan data may be determined from the scan data based on a preset condition. Each of the plurality of target sets of scan data may correspond to a target sub-time period in the scan time period. One or more intermediate images corresponding to one or more sub-time periods different from the plurality of target sub-time periods in the scan time period may be generated based on the plurality of target sets of scan data. A target image sequence of the object may be generated based on the plurality of target sets of scan data and the one or more intermediate images.

The invention provides a total electron amount calculation and correction method for space-based detection ionosphere data. The method comprises the following steps: converting an earth-fixed coordinate system; calculating collision parameters; sorting collision parameters and phase arrays; performing phase calibration; and obscuration correction of the total electron amount. The method has the beneficial effects that according to the forward relation between the total electron content of the ionosphere and the additional time delay of radio wave propagation caused by the ionosphere, the accurate total electron content is obtained from the satellite-ground radio detection ionosphere data by using a calculation and correction method; the method is of great significance in the aspects of satellite positioning navigation radio wave correction, space environment monitoring and the like.

The invention relates to a method for the in-system calibration of gamma radiation detectors (15) of a positron emission tomograph (10), wherein the tomograph (10) has a receiving space (11) for introducing objects to be measured, around which the radiation detectors (15) are arranged, preferably in pairs opposite one another, with a defined position and orientation. According to the invention, the method comprises: introducing (103) an emission device (5) with a radioactive radiation source (7) into a reference position (R) within the receiving space (11), recording (105) coincidences between one or more pairs (15.1, 15.2) of the detectors (15), and - carrying out (107) virtual collimation, wherein determining (117) interaction positions (PI) comprises determining (119) an interaction depth (PI, T) within the detector (15.1) to be calibrated.

The invention discloses a radioactive labeling method of [18F] trifluoromethyl terminal olefin in the technical field of organic synthesis, under the condition of room temperature, 3, 3-difluoroallyl sulfosalt is used as a precursor, [18F] KF / K222 or [18F] TBAF is used as a fluorinating reagent, acetonitrile is used as a solvent, very high radiochemical yield can be obtained within 30 seconds, the tolerance of functional groups is excellent, and the method is suitable for industrial production. The specific reaction formula is as follows: # imgabs0 #. The method provides a simple and efficient way for producing the [18F] trifluoromethylated terminal olefin compound, so that the [18F] trifluoromethylated terminal olefin compound can be applied to positron emission tomography imaging. According to the method for preparing the 3, 3-difluoroallyl sulfur salt compound, the raw materials are easy to obtain, the cost is low, the operation is simple and convenient, safety and controllability are realized, and the radiation yield of the obtained product is high.

The invention belongs to the technical field of vacuum coating, and relates to an electron gun and ion source collaborative evaporation coating method, a control method and a control system. The electronic gun and ion source collaborative evaporation coating control method comprises the steps that key parameters in the coating process are continuously collected, and an electronic gun beam initial value and an ion source gas flow initial value are dynamically generated according to state diagnosis results of all the parameters; the beam current value of the electron gun and the gas flow value of the ion source are corrected in real time to inhibit the disturbance of the ion source to the beam current of the electron gun, and the electron gun and the ion source are cooperatively regulated and controlled to ensure the precise control of the coating uniformity; the invention further discloses an electron gun and ion source collaborative evaporation coating method, local hot spot compensation and global uniformity compensation are carried out by adopting a film thickness compensation mechanism so as to accurately control the film thickness. According to the invention, the cooperative control of the electron gun evaporation and ion bombardment process is realized, the film adhesion is enhanced, the evaporation coating rate is improved, and the film thickness uniformity is improved.

The embodiment of the invention discloses a double-nuclide PET reconstruction method and device based on a joint Poisson model, and the method comprises the steps: coincidence data collection and random three-coincidence estimation: retaining the photon correlation in decay through a coincidence delay window, and estimating the random three-coincidence through the photon irrelevance between decay; establishing a combined Poisson distribution model, introducing impure electron nuclides, pure electron nuclides and random radioactive source distribution into the distribution model at the same time, and constructing a combined Poisson likelihood function; constructing a prior function according to the image features, and forming a target function with the combined Poisson likelihood function; and solving the maximum posteriori estimation of the target function to obtain the spatial distribution of non-pure electron nuclides, pure electron nuclides and random radioactive sources at the same time. The dual-nuclide PET imaging method can be directly applied to the dual-nuclide PET imaging field based on triple coincidence, and has the advantages of being capable of effectively inhibiting random triple coincidence artifacts and the like.

The invention relates to an oxidase response type molecular probe as well as a preparation method and application thereof, and belongs to the technical field of medical imaging. Aiming at the problem that the inflammation activity is difficult to accurately evaluate in the prior art, the invention provides a molecular imaging probe capable of responding to the activity of in-vivo myeloperoxidase (MPO), and the molecular imaging probe can be used for real-time and non-invasive imaging monitoring of the activity of the in-vivo MPO, so that the activity of the inflammatory reaction of a focus is accurately evaluated. The invention provides a chelating agent with structural characteristics of a chelating unit and an enzyme response unit, and is characterized in that the enzyme response molecular probe is constructed by taking rigid framework cyclohexanediamine (CDTA) as a transition metal chelating unit and taking electron-rich functional groups (such as phenol, catechol or 5-hydroxytryptamine) as the enzyme response unit. The probe is chelated with paramagnetic metal (such as Mn < 2 + >) for magnetic resonance imaging (MRI) or radioactive metal (such as 68Ga) for positron emission tomography (PET), so that specific response to MPO activity is realized. The dynamic stability of the probe is remarkably improved; after the MPO is responded, the relaxation efficiency is improved by 2-3 times, and the sensitivity is optimized; the cytotoxicity is low; in an acute pancreatitis model, the MRI contrast noise ratio (delta CNR) reaches 77.39 + / -7.04 and is 4.2 times that of a control group, the PET uptake rate is remarkably improved, bimodal imaging is supported, and accurate positioning and quantitative evaluation of the inflammation activity are achieved.

This is a Nuclear Fusion Reactor using the Carbon Nitrogen Oxygen Cycle (CNO) to generate energy in the form of heat and anti-matter particles such as positrons. The “Carbon Fusion Reactor” is heated to a self-sustaining reaction by the introduction of sodium 22 which decays into positrons and neon 22 via beta positive decay method heating the plasma to above 16 million kelvin upon reacting with electrons. The device is shaped as a tokomak the hydrogen plasma being contained in a magnetic field that is greater than 10,000 Teslas in magnitude allowing the Carbon Fusion events to happen within the torus shaped reaction chamber at 16 million kelvins or higher temperature.

A back illuminated sensor is included as a collector component of a detector for use in intraoral and extraoral 2D and 3D dental radiography, digital tomosynthesis, photon-counting computed tomography, positron emission tomography (PET), and single-photon emission computed tomography (SPECT). The disclosed imaging method includes one or more intraoral or extraoral emitters for emitting a low-dose gamma ray or x-ray beam through an examination area; and one or more intraoral or extraoral detectors for receiving the beam, each detector including a back illuminated sensor. Within the detector, the beam is converted into light and then focused and collected at a photocathode layer without passing through the wiring layer of the back illuminated sensor.

The present disclosure relates to the field of nuclear imaging and therapy, and more particularly, to high purity copper radiotracer compositions that can be used in imaging (e.g., positron emission tomography (PET) and single photon emission computed tomography (SPECT)) and therapy. More specifically, the present disclosure relates to novel compositions useful for imaging and treating conditions (e.g., prostate cancer, somatostatin receptor expressing tumors, such as neuroendocrine tumors, epithelial tumors), and methods of making such compositions.

A multiplexing scheme for both energy and timing information is provided for a particle detection system having an optical sensor array with multiple optical sensors. Each optical sensor is associated with multiple scintillator modules. The system has a segmented prismatoid light guide comprising multiple prismatoid segments. Each segment is associated with multiple optical sensors, where the optical sensors are adjacent. One end each scintillator module is in contact with its associated optical sensor and the other is in contact with its associated segment. Multiple optical sensors may be connected to an energy readout channel, respectively, such that optical sensors associated with the same segments are not connected to the same energy readout channel. Each energy readout channel has at least two timestamps associated therewith.

A multiplexing scheme for both energy and timing information is provided for a particle detection system having a photosensor array with multiple photosensors. Each photosensor is associated with multiple scintillator modules. The system has a segmented pseudo-prismatic light guide with multiple pseudo-prismatic segments. Each segment is associated with multiple photosensors, and the photosensors are adjacent. Each scintillator module contacts its associated photosensor at one end and its associated segment at the other end. Each of the multiple photosensors may be connected to an energy readout channel, such that photosensors associated with the same segment are not connected to the same energy readout channel. Each energy readout channel has at least two timestamps associated therewith.

A positron emission tomography, PET, imaging system (100) includes a plurality of detector modules (1301 . . . i). Each detector module (1301 . . . i) includes a cooling unit (130c1 . . . i) with a heat-transfer region (170). The heat transfer region (170) of each cooling unit (130c1 . . . i) is thermally coupled to a photodetector array (130b1 . . . i) of the corresponding detector module for cooling the photodetector array. The cooling units are configured to be fluidically coupled in parallel to at least one cooling fluid source.

A positron emission tomography (PET) scanner may include a plurality of gamma radiation detector modules arranged to form a detector ring. Each detector module may include an array of elongated scintillation crystals. With respect to the detector ring, each elongated scintillation crystal includes a proximal end-face, two axially oriented lateral faces, two transaxially oriented lateral faces, and a distal end-face radially oriented into the detector ring to receive a gamma photon. An array of photosensors is positioned along a first of the axially oriented lateral faces of each elongated scintillation crystal to detect scintillation photons. A reflective material is positioned on the proximal end-face, the distal end-face, the transaxially oriented lateral faces, and a second of the axially oriented lateral faces of each elongated scintillation crystal to internally reflect scintillation photons. In various embodiments, a dual-channel processing circuit provides distinct timing and energy signals from the photosensors.

Disclosed herein are methods and apparatus for acquiring positron emission (or PET) data in the presence of ionizing radiation causing PET detector afterglow. In one variation, the method includes adjusting a coincidence trigger threshold of a PET detector during a treatment session. In one variation, the method includes adjusting a gain factor used in positron emission data acquisition (e.g., a gain factor used to multiply and / or shift an output(s) of a PET detector(s)) during a treatment session. In some variations, a method for acquiring positron emission data during a radiation treatment session includes suspending communication between a PET detector and a signal processor of a controller for a predetermined period of time after a radiation pulse is emitted by a linear accelerator.

The invention discloses a proton therapy evaluation method and system, a storage medium and a computer program product, and relates to the field of data processing. The evaluation method comprises the following steps: forming a data set by data pairs of a historical proton beam delivery dose distribution image and a historical positron nuclide distribution image; constructing a first model, and training the first model by using the data set to obtain a second model; inputting the positron nuclide distribution image in the actual proton therapy into the second model to obtain a proton beam delivery dose distribution image in the actual proton therapy; and extracting the falling edge of the far end of the Bragg peak of the proton beam delivery dose distribution image in the actual proton therapy to obtain the range information of the proton beam in the actual proton therapy. According to the method, the delivery condition of the planned dose can be directly reflected, Monte Carlo simulation does not need to be carried out on different patients to obtain reference positron nuclide distribution images, time and computing resources are saved, and each treatment process can be verified.

A system for the safe preparation and injection of a radioactive isotope of H2 15 O for use in positron emission tomography (PET). The invention also relates to a safety valve for controlling the flow rate of H2 15 O used in PET, the use of said safety valve, and a method for preparing and injecting H2 15 O.

A photodetector (90) having an exposure surface (91) has a first photodiode array (1) having a first light entry surface (11) and a second photodiode array (2) having a second light entry surface (21). The first photodiode array (1) has an avalanche photodiode (10). The second photodiode array (2) has a non-amplifying photodiode (10). The first light entry surface (11) and the second light entry surface (21) form sub-surfaces of the exposure surface (91).

A positron emission tomography (PET) scanner includes multiple gamma radiation detector modules arranged to form a detector ring. Each detector module includes an array of elongated scintillation crystals. With respect to the detector ring, each elongated scintillation crystal includes a proximal end face, two axially-oriented side faces, two cross-axially-oriented side faces, and a distal end face oriented radially into the detector ring to receive gamma photons. An array of photosensors is disposed along a first of the axially-oriented side faces of each elongated scintillation crystal to detect scintillation photons. Reflective material is disposed on a second of the proximal end face, the distal end face, the cross-axially-oriented side face, and the axially-oriented side face of each elongated scintillation crystal to internally reflect scintillation photons. In various embodiments, a dual-channel processing circuit provides separate timing and energy signals from the photosensors.

The invention relates to a method for the in-system calibration of gamma radiation detectors (15) of a positron emission tomograph (10), wherein the tomograph (10) has a recording chamber (11) for introducing objects to be measured, around which the radiation detectors (15) are arranged, preferably in pairs opposite one another, with a defined position and orientation. It is proposed that the method comprises: introducing (103) an emission device (5) with a radioactive radiation source (7) into a reference position (R) within the recording chamber (11), recording (105) coincidences between one or more pairs (15.1, 15.2) of the detectors (15), and - performing (107) a virtual collimation, wherein a determination (117) of interaction positions (P I ) determining (119) an interaction depth (P I,T ) within the detector (15.1) to be calibrated.

The invention belongs to the technical field of radionuclide labeled radiochemistry and clinical nuclear medicine, and relates to a radionuclide labeled targeted CD44v6 antagonist as well as a preparation method and application thereof. The invention discloses a polypeptide radiopharmaceutical for CD44v6 targeting and a preparation method of the polypeptide radiopharmaceutical. The radiopharmaceutical is radionuclide-bifunctional chelating agent-CDA6, the radionuclide is labeled with polypeptide through the bifunctional chelating agent-CDA6, and the CDA6 polypeptide is of a straight chain structure composed of six amino acids. The radiopharmaceutical realizes specific nuclear medicine positron emission computed tomography (PET) or single photon emission computed tomography (SPECT) imaging diagnosis and / or radioactive therapy of CD44v6 positive tumors or CD44v6 positive lesions (autoimmune diseases, cardiovascular and cerebrovascular system diseases and the like) through specific recognition of the polypeptide CDA6 on CD44V6 in a living body.

The present invention discloses a multi-nuclide imaging method based on image domain separation, comprising: obtaining the original data of multi-nuclide gamma photons; wherein the multi-nuclide includes a pure positron nuclide and several different impure positron nuclides; processing the original data of the multi-nuclide gamma photons using the three-coincidence technology to obtain a set of double-coincidence data and several sets of three-coincidence data of impure positron nuclides; performing low-dose imaging on the annihilation photon data in the three-coincidence data of several sets of impure positron nuclides respectively, and obtaining several corresponding impure positron nuclide distribution maps; performing image reconstruction on the double-coincidence data to obtain a mixed distribution map of multiple nuclides, and using the mixed distribution map to sequentially separate and process several impure positron nuclide distribution maps, and obtaining corresponding pure positron nuclide distribution maps. The defect that conventional PET cannot distinguish between pure positron nuclides and impure positron nuclides that produce instantaneous photons with a lower probability is solved.

The invention discloses a system and a method for improving the counting rate of a TOF-PET (time of flight-positron emission tomography) system. The system comprises a data processing module and a plurality of acquisition units, wherein each acquisition unit comprises a detector module and an electronics module; the detector module is used for detecting gamma photon pairs generated by positron annihilation in a detected object, converting nuclear signals generated according to the detected gamma photon pairs into electric signals and inputting the electric signals into the electronics module; the electronics module screens the input electric signals to obtain real coincidence cases and collects the real coincidence cases; the data processing module is used for taking the received two real coincidence cases in the same coincidence time window as a pair of real coincidence cases, and calculating the time difference between the two real coincidence cases in each pair of real coincidence cases and the corresponding detector module; and determining the position of the detected object according to the statistical result of the time difference of each pair of real coincidence cases. The theoretical effective counting rate can be increased by several times or even one magnitude, and the sensitivity of the system is greatly improved.

A method for estimating noise equivalent counts includes one or more times during a scan of an object with a positron emission tomography (PET) scanner, wherein a plurality of coincidence events are detected by a detector array of the PET scanner, performing the following actions. The actions include obtaining a total of the plurality of coincidence events, estimating random coincidence events, and estimating scatter coincidence events. The actions include estimating true coincidence events based on the total of the plurality of coincidence events, the estimated random coincidence events, and the estimated scatter coincidence events. The actions include determining a scatter fraction based on the estimated scatter events and true coincidence events. The actions include estimating the noise equivalent counts based at least on the scatter fraction, the total of the plurality of coincidence events, the estimated true coincidence events, the estimated scatter coincidence events, and the estimated random coincidence events.

This invention relates to a convolution-based method for noise suppression in positron emission tomography (PET) flow field images, comprising the following steps: S1, obtaining consistent data through CFD flow field simulation and GATE detection system simulation, and reconstructing a low-resolution initial image of the PET flow field containing noise using the OSEM algorithm; S2, constructing a noise suppressor model, inputting the low-resolution initial image into the model, and outputting a noise-suppressed flow field feature image using a deep convolutional network and multi-scale feature fusion technology; S3, constructing a multi-loss fusion evaluation system, using mean squared error loss, minimum absolute value deviation loss, and perceptual loss to jointly constrain model training, and iteratively updating the weights using the Adam optimizer. This invention not only improves the enhancement model's ability to distinguish noise information, thereby enhancing the model's ability to remove noise information from PET images, but also significantly improves evaluation metrics such as PSNR and SSIM.

An iterative statistical algorithm based on a discrete-to-discrete data model with iterative coordinate descent optimization for image reconstruction from radiation measurements obtained in emission tomography, i.e. in a Positron Emission Tomography scanner, is described in this invention. The method presented here allows for the presence of the regularization as an additive term. Furthermore, this method makes it possible to control the convergence of the algorithm using a specific parameter. These improvements are due to the signals obtained regarding the given statistics of this imaging technique.

The invention belongs to the technical field of inorganic scintillator materials, and particularly relates to a multi-element co-doped yttrium lutetium silicate scintillator and a preparation method and application thereof, and the material has excellent comprehensive performance of high light output, short decay time, high radiation hardness, high matching degree of emission spectrum and novel photoelectric sensors and the like. The invention further relates to a preparation method of the scintillator material and application of the scintillator material in radiation detection fields such as positron emission tomography (PET), time flight PET (TOF-PET), interaction depth PET (DOI-PET), single photon emission computed tomography (SPECT), high-energy physical experiments, nuclear medicine imaging, industrial nondestructive inspection, safety detection (such as luggage and cargo container inspection) and the like.

The invention discloses a molecular imaging probe targeting poly ADP ribose polymerase as well as a preparation method and application of the molecular imaging probe. The molecular imaging probe is represented by the following formula Ia or Ib. The compound disclosed by the invention can be used as a PARP-targeted positron emission, single photon emission or nuclear magnetic resonance imaging probe, and has a great application prospect in imaging treatment of PARP expression abnormity related diseases such as tumors. # imgabs0 #