Abstract: A radiation detector is provided that allows correction so as to identify incident gamma-ray positions accurately with no influence of afterglow of fluorescence. The radiation detector includes an intensity-data acquiring section for acquiring intensity data representing intensity of fluorescence outputted from a light detector for every temporally-constant sampling interval, and a correction-value acquiring section section for acquiring a correction value used for correction of variations in intensity data resulting from afterglow of the fluorescence. In addition, the radiation detector includes an integrating section for correcting the intensity data using the correction value. This allows correct calculation of the integrated value m with no influence of the afterglow of fluorescence.

Abstract: A method for cardiac imaging is provided, including administering to an adult human subject an amount of a teboroxime species having a radioactivity of less than 5 mCi at a time of administration, and performing a SPECT imaging procedure of a cardiac region of interest (ROI) of the subject. Other embodiments are also described.

Abstract: Detector crystals in a positron emission tomography (PET) apparatus gantry are cooled by directing cooling gas flow into a cooling duct bounded by the crystals and a cover defining the patient scanning field within the gantry. The cooling gas cools the crystals. Cooling gas may also be directed radially outwardly from the cooling duct into spatial gaps defined between detector enclosures that include the crystals, further isolating heat generated by other components within gantry from the detector crystals. Cooling gas is provided by a cooling system that may be incorporated within the gantry, external the gantry or a combination of both. Cooling gas can be provided by directing air within the gantry in contact with internal gantry cooling tubes and routing cooled air directly into the cooling duct with a powered fan.

Abstract: A multi-view composite collimator includes a first parallel collimator segment having a plurality of collimator channels oriented at a first slant angle and a second parallel collimator segment adjacent to the first parallel collimator segment having a plurality of collimator channels oriented at a second slant angle different from the first slant angle and a bridging collimating element is provided between the first and second parallel collimator segments, wherein radiation can pass through the bridging collimating element.

Abstract: A PET scanner (8) includes a ring of detector modules (10) encircling an imaging region (12). Each of the detector modules includes at least one detector pixel (24,34). Each detector pixel includes a scintillator (20, 30) optically coupled to one or more sensor APDs (54) that are biased in a breakdown region in a Geiger mode. The sensor APDs output a pulse in response to the light from the scintillator corresponding to a single incident radiation photon. A reference APD (26, 36) also biased in a break-down down region in a Geiger mode is optically shielded from light and outputs a temperature dependent signal. At least one temperature compensation circuit (40) adjusts a bias voltage applied to the sensor APDs based on the temperature dependent signal.

Abstract: The present disclosure relates to the correction of charge loss in a radiation detector. In one embodiment, correction factors for charge loss may be determined based on depth of interaction and lateral position within a radiation detector of a charge creating event. The correction factors may be applied to subsequently measured signals to correct for the occurrence of charge loss in the measured signals.

Abstract: A gamma ray detector for detecting a gamma ray emitted from a target of measurement includes: an organic scintillator for detecting Compton electrons resulting from a gamma ray emitted from the target of measurement; an inorganic scintillator for detecting a Compton gamma ray; and photodetector modules for detecting light generation in the corresponding scintillators. Light generation signals from the organic and inorganic scintillators are synchronously measured, and a detection window of a gamma ray is generated. Thus, an inexpensive radiation diagnostic device of an ultra-high S/N ratio and low cost is provided.

Abstract: A biopsy grid is provided that is useful in medical imaging. The biopsy grid comprises a hydrogel layer containing a mixture of contrast agents that are visible in images from X-ray, CT scans, MRI, and/or positron emission tomographs. The hydrogel mixture is attached to a frame having a silicone coated release liner and an adhesive layer. The hydrogel layer is cut into strips that serve as markers in an image. The biopsy grid can be used to locate the position of the marker relative to a tissue of interest in a medical image.

Abstract: A method for producing a single crystal scintillator material according to the present invention includes the steps of: providing a solvent including: at least one element selected from the group consisting of Li, Na, K, Rb and Cs; W and/or Mo; B; and oxygen; melting a Ce compound and a Lu compound that have been mixed with the solvent by heating the mixture to a temperature of 800° C. to 1,350° C.; and growing a single crystal by cooling the compounds melted. The single crystal is represented by the compositional formula (CexLu1-x)BO3, in which the mole fraction x of Ce satisfies 0.0001?x?0.05.

Abstract: Systems and methods for nuclear medicine (NM) imaging using different radiopharmaceuticals are provided. One method includes generating images of a region of interest (ROI) from radioactive emissions from a localization radiopharmaceutical to position the ROI in a field-of-view (FOV) of a gamma camera based on the generated images of the ROI. The method further includes performing an imaging scan of the ROI using an imaging radiopharmaceutical to acquire image data of the ROI, wherein the imaging radiopharmaceutical is different than the localization radiopharmaceutical.

Abstract: A detector arrangement of an imaging system detector detecting ionizing radiation includes a detector carrier, a plurality of detector modules attached to the detector carrier, and a collimator disposed in the radiation direction in front of the detector modules which are disposed on the incident radiation measurement side. In at least one embodiment, at least one air gap is included for conveying cooling air is disposed between the collimator and the measurement sensors of the detector modules. A method is also disclosed for cooling a detector arrangement of a detector rotating around a system axis with a plurality of measurement sensors disposed next to one another and a collimator arranged in the radiation direction in front of the measurement sensors, wherein cooling air is conveyed in or against the system axis direction between the collimator and the measurement sensors which directly cools the surface of the measurement sensors.

Abstract: A positron emission computed tomography apparatus according to an embodiment includes a detector, a coincidence counting information generating unit, and a body movement detecting unit. The detector detects annihilation radiation released from a subject. The coincidence counting information generating unit searches for sets of counting information, which counted a pair of annihilation radiations at substantially the same time, from a counting information list that is generated from output signals of the detector; generates a set of coincidence counting information for each retrieved set of counting information; and generates a time series list of coincidence counting information. Based on the time series list of coincidence counting information, the body movement detecting unit detects temporal changes in the body movement of the subject.

Abstract: In the nuclear medicine imaging apparatus according to the one embodiment, the ADC converts the output data of each of the photodetectors to digital data. The counting information collecting unit collects counting results from the digital data, and the counting information storage unit stores the counting result in association with the digital data. The coincidence counting information generating unit generates coincidence counting information. The image reconstructing unit reconstructs a PET image, based on the coincidence counting information. The time correction data stores a correction time for each of the photodetectors. The system controlling unit controls to correct the detection time of the gamma rays in the digital data associated with each piece of the counting information by use of the correction time, and to generate new coincidence counting information. The system controlling unit controls to reconstruct a new nuclear medicine image, based on the new coincidence counting information generated.

Abstract: A method and system for reconstructing an image of an object. The method includes acquiring an image dataset of an object of interest, identifying valid data and invalid data in the image dataset, determining a time period that includes the valid data, weighting the valid data based on the determined time period, and reconstructing an image of the object using the weighted valid data.

Abstract: Systems and methods for communicating dose calibration information are provided. One method includes determining dose calibration information of a radiopharmaceutical at a dose calibrator. The method also includes automatically storing the dose calibration information in a memory. The method further includes communicating the stored dose calibration information to a host system.

Abstract: Radioimaging methods, devices and radiopharmaceuticals therefor.

Abstract: Detector crystals in a positron emission tomography (PET) apparatus gantry are cooled by directing cooling gas flow into a cooling duct bounded by the crystals and a cover defining the patient scanning field within the gantry. The cooling gas cools the crystals. Cooling gas may also be directed radially outwardly from the cooling duct into spatial gaps defined between detector enclosures that include the crystals, further isolating heat generated by other components within gantry from the detector crystals. Cooling gas is provided by a cooling system that may be incorporated within the gantry, external the gantry or a combination of both. Cooling gas can be provided by directing air within the gantry in contact with internal gantry cooling tubes and routing cooled air directly into the cooling duct with a powered fan.

Abstract: In a method and apparatus for establishing the position of one or more constituent elements of a phantom in an image quality test for a medical imaging apparatus, an image of the phantom is obtained, and a landmark pixel or region of the image determined. Values of a given variable at pixels or regions at a predetermined distance from the landmark pixel or region are determined. The landmark pixel or region and the values of the variable are then used to establish the position of one or more of the constituent elements of the phantom.

Abstract: Nuclear imaging systems, non-transitory computer readable media and methods for adaptive imaging are presented. Particularly, the present method includes acquiring preliminary projection data by scanning each of one or more views of a subject for a determined preliminary scan interval. Further, a region of interest of the subject is identified. The preliminary projection data is then used to perform a constrained optimization of a rapidly computable image quality metric for determining an acquisition protocol that improves the image quality metric at the identified region of interest. Particularly, the determined acquisition protocol is used to acquire target projection data corresponding to at least the identified region of interest. Further, an image of at least the identified region of interest is reconstructed using the target projection data, the preliminary projection data, or a combination thereof.

Abstract: Improved processing electronic hardware are disclosed that facilitate the efficient processing of PET system data, while enhancing accuracy and compatibility of PET systems with other analytical methods (e.g., magnetic resonance imaging). Improvements include the use of an application-specific integrated circuit (ASIC) for summing, by row, column, and diagonal, the output signals from an array of photodetectors in the PET system.

Abstract: Systems and methods are described herein for performing three-dimensional imaging using backscattered photons generated from a positron-electron annihilation. The systems and methods are implemented using the pair of photons created from a positron-electron annihilation. The trajectory and emission time of one of the photons is detected near the annihilation event. Using this collected data, the trajectory of the second photon can be determined. The second photon is used as a probe photon and is directed towards a target for imaging. The interaction of the second probe photon with the target produces back scattered photons that can be detected and used to create a three-dimensional image of the target. The systems and methods described herein are particularly advantageous because they permit imaging with a system from a single side of the target, as opposed to requiring imaging equipment on both sides of the target.

Abstract: Systems and methods are described herein for performing three-dimensional imaging using backscattered photons generated from a positron-electron annihilation. The systems and methods are implemented using the pair of photons created from a positron-electron annihilation. The trajectory and emission time of one of the photons is detected near the annihilation event. Using this collected data, the trajectory of the second photon can be determined. The second photon is used as a probe photon and is directed towards a target for imaging. The interaction of the second probe photon with the target produces back scattered photons that can be detected and used to create a three-dimensional image of the target. The systems and methods described herein are particularly advantageous because they permit imaging with a system from a single side of the target, as opposed to requiring imaging equipment on both sides of the target.

Abstract: A smart sensor for maintaining constant gain in a photosensor despite temperature is disclosed. The smart sensor receives temperature data from a temperature sensor, then compares the temperature data to a lookup table of temperatures corresponding to voltages which, when applied to a photosensor at that temperature, will produce a desired gain. The smart sensor then applies the voltage from the lookup table to the photosensor, to yield a desired gain from the photosensor. The smart sensor is particularly applicable to SiPMs used in PET/MRI imaging systems.

Abstract: The present disclosure relates approaches for removing or reducing the effects of motion in parallel and non-parallel data acquisitions using a nuclear medicine imaging system. In certain embodiments, translation vectors are derived based on a registration performed on transaxial slices generated from the acquired projection data. The translation vectors may be employed to update a system matrix such that images generated using the updated system matrix are free or motion artifacts or have reduced motion artifacts.

Abstract: Disclosed herein are a system, method, and computer-readable storage medium for determining a time pickoff for both digital and analog photomultiplier circuits. Rather than basing time pickoff on the leading edge of a photomultiplier signal crossing a threshold or the first signal from a digital photomultiplier, a method for more accurate time calculations is disclosed. The system searches for peak values associated with the signal using differentiation, peak hold searching, and Gaussian distributions. Based on these calculations and comparisons, a more accurate time pickoff is determined.

Abstract: A positron emission tomography method and a device with application adaptability. The method includes: 1. scanning a tested object initially for obtaining initial activity information of the tested object; 2. programming and adjusting a detector module based on the result of the initial scan so as to obtain a new system structure, and rapidly calibrating the new system structure; 3. performing a scan with the new system structure for obtaining activity information of the tested object; 4. analyzing the activity information of the tested object obtained at step 3. If quality of the activity information can satisfy requirements of the application, the scan is finished; otherwise programming and adjusting the detector module is repeated, rapid calibration is performed, and the activity information of the tested object is obtained again with the new system structure until the activity information satisfies requirements of the application.

Abstract: According to one embodiment, a TOF-PET apparatus includes a plurality of detector rings arranged along a central axis thereof. Each of the detector rings comprises a plurality of scintillators and a plurality of photomultipliers. The scintillators are arranged on a substantial circumference around the central axis and generate scintillation in response to pair annihilation gamma-rays from a subject. The photomultipliers generate an electric signal in accordance with the generated scintillation. A length of each of the scintillators along a radial direction of the substantial circumference is set to a range in which a value of a total number of counts/time resolution of coincidence events of pair annihilation gamma-rays is more improved than when a reference scintillator whose probability of interaction with pair annihilation gamma-rays is adjusted to 80% is used under conditions of a constant total volume of the scintillators.

Abstract: Using standard or “off the shelf” cable to interconnect between the PET block detector and the detector circuit may save substantial costs given the number of PMTs in a PET system. Given space constraints, simple maintenance with reduced risk of disturbing cabling is desired, making ongoing use of standard cabling without adding further cabling desired. To implement digital gain control, a further communication is provided between the PET detector block and the detector circuit. Since the standard cable may not have additional wires for such communications and to reduce timing degradation, the PMT signals are combined, such as generating position and energy signals at the PET detector block. The four PMT signals are reduced to three signals without reduction in function, allowing a fourth twisted pair of wires in a CAT5 cable to be used for digital gain control.

Abstract: A PET apparatus and a timing correction method of this invention select two target gamma-ray detectors which count coincidences, select a reference detector which is one detector out of the two selected gamma-ray detectors, select a gamma-ray detector different from the other, opposite detector, and when repeating the selection, make a time lag histogram concerning two gamma-ray detectors selected in the past a reference, and correct a time lag histogram concerning gamma-ray detectors selected this time based on the reference. By repeating an operation to make the corrected time lag histogram concerning the two gamma-ray detectors a new reference, an optimal time lag histogram can be obtained without repeating many measurements and computations.

Abstract: A detector of a high-energy photon, the detector including a photodetector and a detection medium that is intended to absorb a high-energy photon while generating ionization electrons and photons along a luminous phenomenon, the electrons and photons being detected by the photodetector. The detection medium is formed of molecules, having a heavy atom with an atomic number greater than or equal to 72, such that the detection medium is liquid under the operating conditions of the detector. The detector also includes a device for diverting the ionization electrons that are generated by the absorbed photon and moreover includes a collector that collects charges in order to determine the time for diverting the electrons to the charge-collector on the basis of a triggering time that corresponds to the detection of the luminous phenomenon by the photodetector.

Abstract: A three-dimensional position-sensitive radiation detector is provided which has a three-dimensional array of photodetectors disposed on the surface of a scintillator block and which is capable of three-dimensionally identifying the position of light emission at which radiation has been detected within the detector. The three-dimensional position-sensitive radiation detector includes: a scintillator block including a central portion which restricts the direction of diffusion of light so as to direct the light in three axial directions and which has an optically discontinuous region, and an outer portion which is disposed on the outside of the central portion and which does not restrict the direction of diffusion of light; and photodetectors disposed on at least two outer circumferential surfaces of the scintillator block.

Abstract: A system and method for reconstructing single photon emission computed tomography data acquired with a pinhole collimator includes sub-dividing each voxel in the imaging target object space into sub-voxels and sub-dividing each of the detector bins in the gamma camera detector into sub-bins, connecting the centers of each of the sub-voxels to each of the detector sub-bins through a pinhole provided in the pinhole collimator by ray tracing and for each ray connecting the centers of each of the sub-voxels to each of the detector sub-bins, the transmission probability is calculated by analytically solving the intersections between the ray and the pinhole surfaces. Then, a geometric-response-function of the pinhole collimator is computed which is then convolved with the intrinsic-response-function of the detector to obtain the PSF.

Abstract: Determining the position of a radioactive source in a PET system. Detecting a scatter coincidence event characterized by a full-energy photon detected at a first detector and partial-energy photon at a second detector. Measuring the arrival time difference between the partial energy photon and the full energy photon. Measuring the energy of the partial-energy photon. Determining a scattering point as a function of the position of the first detector, the position of the second detector, the energy of the partial-energy photon, the energy of an unscattered photon, the mass of a scattering electron, and the speed of light. Determining the position of a radioactive PET source along a line between the scatter point and the first detector as a function of the distance between scatter point and the first detector, the distance between scatter point and the second detector, and the measured time difference.

Abstract: A PET apparatus includes an optical coupling detachment testing unit. In one example, the optical coupling detachment testing unit inputs an electric signal to a piezoelectric element or the like adhered to a detector module and generates a sound wave within the detector module. Further, the optical coupling detachment testing unit detects the sound wave propagated within the detector module and performs a frequency analysis on the detected sound wave. Subsequently, as a result of the analysis, the optical coupling detachment testing unit detects whether an optical coupling detachment has occurred by looking for a frequency distribution specific to a surface having an optical coupling detachment and/or comparing a frequency distribution with another frequency distribution from a previous test.

Abstract: Apparatuses, computer-readable mediums, and methods are provided. In one embodiment, a positron emission tomography (“PET”) detector array is provided which includes a plurality of crystal elements arranged in a two-dimensional checkerboard configuration. In addition, there are empty spaces in the checkerboard configuration. In various embodiments, the empty spaces are filled with passive shielding, transmission source assemblies, biopsy instruments, surgical instruments, and/or electromagnetic sensors. In various embodiments, the crystal elements and the transmission source assemblies simultaneously perform emission/transmission acquisitions.

Abstract: A method of configuring a time-of-flight positron emission tomography (PET) system includes determining a set of parameters of a detector of the PET system. Each parameter is configured to affect photon travel within the detector. The method further includes simulating operation of the detector to generate a photon detection timing data profile for a plurality of depth of interaction (DOI) positions within the detector via a simulation model of the detector configured in accordance with the set of parameters, and determining a time-of-flight correction factor for each DOI position of the plurality of DOI positions based on the simulated operation. The correction factor is indicative of a time offset of the photon detection timing data profile.

Abstract: Methods and systems for multiple scatter estimation in Positron Emission Tomography (PET) are provided. One method includes determining attenuation sinograms and determining a varying convolution kernel as a function of the attenuation sinograms, wherein the kernel varies in amplitude and width over a radial length of a PET imaging system. The method also includes using the varying convolution kernel to estimate multiple PET scatter.

Abstract: Provided are a proximity imaging type PET apparatus and a system which include a part-specific PET scanner disposed in proximity to a specific part of a measurement target and a whole-body PET scanner which is capable of radiographing the whole body of the measurement target, the PET apparatus and system being capable of bringing PET detectors into close proximity to the specific part of the measurement target so as to ensure higher sensitivity and imaging a wide field of view.

Abstract: For coincidence determination, a PET device that regards and counts a pair of annihilation radiations detected within a predetermined time as occurring from the same nuclide changes a coincidence time width according to a maximum detection time difference. This prevents the inclusion of extra noise data for improved image quality.

Abstract: A method (70) of operation of a PET scanner (10) that determines the depth of interaction of the annihilation photons within the scintillator (32) in localizing a temporal photon pair along a line of response (LOR).

Abstract: The current invention is generally related to a data acquisition and or image processing method and system for acquiring and or processing sparse channel data. The sparse channel is implemented in a data acquisition system having a predetermined wider pitch between the adjacent detector cells than that in the currently available imaging systems at least in one predetermined channel direction. The sparse channel is also defined to encompass various imaging modalities including CT, positron emission tomography (PET) and positron emission tomography-computed tomography (PET/CT). The sparse channel data is acquired by the sparse channel data acquisition system, and an image is reconstructed from the sparse channel data according to a predetermined iterative reconstruction technique.

Abstract: A system and method are provided for determining the onset of gamma interactions for positron emission tomography (PET) imaging more accurately than with existing techniques. The timing of a sequence of primary trigger events is obtained and used to determine a weighted combination, which mixes the timing information from the various primary trigger events to compute an overall event trigger timing with improved time resolution. Numerical simulations demonstrate that the invention improves time resolution by approximately 10% over state-of-the-art methods. This improved time resolution directly benefits the imaging performance of the PET scanner, especially in time-of-flight (TOF) mode, where a high time resolution directly translates to a reduction in image noise at the same dose—or, alternatively, a reduction of dose to the patient or scan time for the same image quality.

Abstract: Systems, devices, and methods are provided for more efficient photon detection in nuclear medical imaging. By basing the density of photosensitive microcells in photosensors on a spatial distribution of photons across the array of photosensors, the non-linearity of the photosensors' output pulses can be reduced, and the negative effects of non-uniform distribution of light from a scintillator array can be ameliorated. As a result, the positioning and linearity information of typical photosensors used in nuclear medical imaging can be improved, and better quality images are produced.

Abstract: In a coincidence determination processing of a PET device for regarding and counting a pair of annihilation radiations detected within a predetermined time as occurring from the same nuclide, a priority of a line of response to acquire is set and a true coincidence is extracted from multiple coincidences by using information on a detection time difference if a plurality of coincidences are detected with the predetermined time. Consequently, a true coincidence is extracted from multiple coincidences which have heretofore been discarded. This improves detection sensitivity at high radioactive concentration and contributes to an improved dynamic range.

Abstract: A high-resolution nuclear imaging detector for use in systems such as positron emission tomography includes a monolithic scintillator crystal block in combination with a single photomultiplier tube read-out channel for timing and total energy signals, and one or more solid-state photosensor pixels arrays on one or more vertical surfaces of the scintillator block to determine event position information.

Abstract: A programmable memory is provided in each of a plurality of detector modules arrayed in a positron emission tomography (PET) scanner. Each detector module memory stores data associated with its respective detector module. Each memory may be coupled to a processor via a transmission bus. A display device may be coupled to the processor for displaying information relating to information obtained from the detector module memories.

Abstract: In nuclear imaging, solid state photo multipliers (48) are replacing traditional photomultiplier tubes. One current problem with solid state photomultipliers, is that they are difficult to manufacture in the size in which a typical scintillator is manufactured. Resultantly, the photomultipliers have a smaller light receiving face (50) than a light emitting face (46) of the scintillators (44). The present application contemplates inserting a reflective material (52) between the solid state photomultipliers (48). Instead of being wasted, light that initially misses the photomultiplier (48) is reflected back by the reflective material (52) and eventually back to the radiation receiving face (50) of the photomultiplier (48).

Abstract: A PET instrument free from problems of maintenance of a detector when a field of view in a body axial direction of a subject is significantly enlarged. A gantry (1) is divided into a plurality of units (5) in the body axial direction of the subject. Each unit (5) is configured to be movable in an orthogonal direction to the body axial direction. Further, a number of detectors are provided in each unit (5) and arranged in its circumferential direction and the body axial direction.

Abstract: A method for processing events in a medical imaging device may comprise the steps of receiving analog signals from at least one PMT into an Applied Specific Integrated Circuit (ASIC) comprising a Constant Fraction Discriminator (CFD) and transmitting analog outputs from the ASIC. Further, sampling the analog outputs continuously using an Analog to Digital Converter (ADC) and transmitting digital outputs; and collecting a number of samples of the digital output during a sampling period using a Field Programmable Gate Array (FPGA) when triggered by the CFD. The method may additionally determine the energy of the analog signals from the at lease one PMT by subtracting the peak value of each signal from the baseline value of each signal, wherein the peak value is determined as an average of at least one sample taken only around the peak during the sampling period, and the baseline value is determined as an average of at least one sample taken only around the beginning or end of the sampling period.

Abstract: A method for extracting photon depth of interaction information in a positron emission tomography system is provided. A pulse is detected in a photodetector. A height of the pulse is measured. A determination of whether the pulse height is within a set range is made. Photon depth of interaction is extracted from the pulse height. An energy of interaction is calculated from the pulse height and calibration data. The extracted photon depth and calculated energy spectrum are used in image reconstruction.