166 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.

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 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 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.

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) 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.

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.

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 #

The current disclosure provides systems and methods for increasing a quality of positron emission tomography (PET) images generated by a PET system with detectors including bismuth germinate (BGO) crystals. In one example, a method for the PET system comprises extracting a higher-quality 2-D image from a first image volume reconstructed using higher-quality time-of-flight (TOF) data acquired from a subject during a scan performed using the PET system, the TOF data based on Cherenkov radiation detected at the BGO crystals; extracting a lower-quality 2-D image from a second image volume reconstructed using lower-quality TOF data acquired from the subject by the PET system; generating an enhanced-quality 2-D image from the lower-quality 2-D image using a trained image quality enhancement model; merging the enhanced-quality 2-D image with the higher-quality 2-D image; and displaying the merged 2-D image on a display device of the PET system.

Methods and apparatus are disclosed for concurrent digital autoradiography of alpha-particle events and positron events using a spatially resolving charged particle detector and a gamma-ray detector. Alpha particles and positrons are detected by the charged particle detector. Positrons are identified based on coincidence with gamma-ray events. A positron-emission autoradiograph is formed based on positron positions. Alpha particles, both coincident and anticoincident with positrons, are identified based on energy deposition patterns. An alpha-emission autoradiograph is formed based on alpha-particle positions and energies. Separation of coincident alpha and positron events recorded by the charged particle detector improves position detection accuracy. Validation of positron imaging for alpha-emitter distribution or dosage, based on correlation of respective autoradiographs, is described. Variations for particle identification based on isotropy, energy, coincidence, or anticoincidence are presented. Disclosed techniques are applicable to alpha-emitting radionuclides with complex decay chains.

The present disclosure provides a modular radiation therapy apparatus comprising a plurality of modules configured to sequentially interlock within one another in an annular arrangement, wherein the plurality of modules are individually extractable from the annular arrangement and at least a subset of the plurality of modules comprise computing elements configured to communicate with one another, the plurality of modules comprising a collimator module comprising a multi-leaf collimator (MLC) and at least one sensor, a linear accelerator (LINAC) module comprising at least one of a magnetron or a klystron, at least one imaging module comprising at least one of an image detector, an imaging source, a magnetic imaging system, a single photon emission computed tomography (SPECT) system, or a positron emission tomography (PET) system, a patient tracking module, a cooling module, and a vacuum module, and performing at least one of: monitoring a respective status of the plurality of modules via onboard sensors and computing elements to determine whether any module is in an error state and provisioning status information and module identifiers to a remote computing environment; or distributing computational workloads among the plurality of modules and communicating with a remote computing environment to offload processing tasks using federated processing operations.

A holding device (3) for a medical imaging device, in particular in the form of a positron emission tomography (PET) scanning device (1), is provided. A holding device (3) is used to hold a medical imaging phantom (2) in a defined position inside a detector ring (11) of a medical imaging device. The retaining device (3) is adapted to be attached to an axial end face (113; 114) of the detector ring (111). The invention further relates to a phantom unit comprising such a holding device (3) and a medical imaging phantom (2) and to a method for securing a quality standard for a medical imaging device (1) and for calibrating a medical imaging device (1).

The invention belongs to the technical field of PET (positron emission tomography), and relates to a PET probe extensive field image multi-model adaptive deformation and FPGA (field programmable gate array) curing method, which comprises the following steps of: acquiring single-lift event data of a PET probe; generating an original extensive field image based on the single-lift event data; performing coordinate traversal transformation on the original extensive field images by adopting an image deformation model in a preset multi-model transformation library; performing off-line analysis on each model and the parameters thereof in the multi-model transformation library by utilizing a preset evaluation index, and screening out an optimal model and an optimal parameter; and transforming the original pan-field image by using the optimal model and the optimal parameters to generate an enhanced image and a crystal position lookup table, and solidifying the enhanced image and the crystal position lookup table to the FPGA. The method has the beneficial effects that the local adhesion area can be stretched in a targeted manner through the nonlinear transformation model, the distinction degree of crystal event clusters is remarkably improved, and the LUT calibration precision is fundamentally improved.

A method for determining a convolution kernel for an iterative statistical algorithm based on a continuous-to-continuous data model. The method is used for image reconstruction from radiation measurements obtained in emission tomography, specifically in a Time-of-Flight Positron Emission Tomography (TOF PET) scanner. The presented method is a non-list-mode solution that reduces the computational complexity of the reconstruction problem, improves the resolution of reconstructed images, reduces the radiation dose absorbed by patients during TOF PET examinations, and / or shortens the measurement acquisition time without significantly compromising the quality of the diagnostic images. Notably, the quality of the functional images remains at the same level. These improvements are achieved by designing the convolution kernel to account for the statistical properties of the measurement signals registered during the TOF PET scanner's acquisition process.

To provide both good time-of-flight resolution and interaction depth information. [Solution] The positron emission tomography apparatus according to the embodiment comprises a scintillation array and a photosensor array. The scintillation array includes a plurality of scintillator crystal units individually separated by a reflective material, and each scintillator crystal unit is configured to generate scintillation light in response to gamma-ray interactions within the scintillator crystal unit caused by gamma-ray irradiation from a subject, and has a substructure for decoding two or more depths within the scintillator crystal unit such that gamma-ray interactions at different depths cause scintillation light to escape from the photo-escape plane of the scintillator crystal unit in different patterns. The photosensor array converts the scintillation light received from the scintillation array into an electrical signal.

The invention discloses a day and night transition area electron density inversion method, which comprises the following steps: firstly, starting from extracting a solar zenith angle of a VLF wave propagation path at different moments, providing a subsection correction electron density model suitable for a low ionosphere, and introducing the correction electron density model changing along with the zenith angle into a frequency domain finite element method; a ground-ionosphere waveguide VLF wave amplitude and phase propagation data set is constructed, VLF wave simulation and test data are introduced into an artificial intelligence model, and inversion of corrected electron density parameters is realized. According to the method, the zenith angle and the corrected electron density model are introduced, and VLF wave propagation numerical simulation and experimental testing are combined, so that the constructed artificial intelligence model can quickly and accurately predict the electron density of the day and night transition region of the ionosphere D region.

Structural design of cranial nerve degeneration contrast agent precursor, the cranial nerve degeneration contrast agent prepared using the cranial nerve degeneration contrast agent precursor can be used for positron radiation tomography to detect alpha-synuclein. Since the cranial nerve degeneration contrast agent has better affinity and specificity for α-synuclein, it is helpful for more efficient early diagnosis of Parkinson's disease.

There is provided a positron source (10; 1000) for generating a positron beam (180), wherein the positron source (10; 1000) includes: a laser arrangement (50) configured to generate a pulsed beam (70) of photons; a target (30) configured to receive the beam (70) of photons, wherein the target (30) is arranged for the photons of the beam (70) to generate a photon plasma at a surface layer (40) of the target (30), wherein the surface layer (40) is configured to preferentially absorb electrons from the photon plasma to generate corresponding free positrons; and an electrode arrangement (160) comprising one or more electrodes (160A, 160B, 160C) that are configured to apply an electric field to the photon plasma to extract the free positrons therefrom and to guide the positrons to form the positron beam (180). At least the target (30) and the electrode arrangement (160) are included within a vacuum chamber (20) configured in use to provide a vacuum condition in which the target (30) and the electrode arrangement (160) are arranged to function. Optionally, the surface layer (40) is configured to include a doped semiconductor material for providing the surface layer (40). More optionally, the doped semiconductor includes at least one of: p-doped Silicon, p-doped Gallium Arsenide, p-doped Graphene, Graphene, p-doped Silicon Carbide.