Abstract: Apparatus and systems may operate to enable positron emission imaging with a unitary chamber body having an open end that defines a hollow interior portion shaped to completely contain a flexible sleeve that is used to cover a core sample when the sleeve is seated within the hollow interior portion. An end cap may be formed to engage the open end of the chamber body, which is configured to attenuate gamma rays approximately eight times less than stainless steel, while supporting a pressure differential of at least 3 MPa between the chamber inlet and the outlet when fluid carrying a radioactive tag to generate the gamma rays flows through the hollow interior portion and the core sample via the inlet and the outlet. Additional apparatus, systems, and methods are disclosed.

Abstract: A positron emission tomography (PET) detector module includes an array of scintillation crystal elements and a plurality of photosensors arranged to at least partially cover the array of scintillation crystal elements. The photosensors are configured to receive light emitted from the array of scintillation crystal elements. The module includes a transparent adhesive arranged between the array of scintillation crystal elements and the plurality of photosensors. The transparent adhesive extends directly from a surface of at least one of the scintillation crystal elements to a surface of at least one of the photosensors and is configured to distribute the light emitted from one of the scintillation crystal elements to more than one of the photosensors. A method of manufacturing the module includes various steps utilizing a fixture. A PET scanner uses multiple modules arranged circumferentially around an area to be scanned.

Abstract: An apparatus and method are provided for optimizing an amount of radiation dose and acquisition time in cardiac Single Photon Emission Computed Tomography (SPECT) imaging. The apparatus and method include providing an organ, acquiring images of the organ at projected views. Then a projected view that projects the organ as an annulus is selected; a region of interest (ROI) is also selected in the projected view, wherein the ROI is in a lateral wall of the organ. An average count in the ROI is determined; and an image quality of a reconstructed image based on the average count is predicted.

Abstract: An integrated Positron Emission Tomography (PET)/Computed Tomography (CT) system includes a patient support device supporting a patient pallet, a gantry having a space through which the patient pallet passes, a plurality of integrated PET/CT detector modules attached to one side of the gantry, an x-ray tube attached to the other side of the gantry, and a signal detecting/processing unit. Each of the plurality of integrated PET/CT detector modules include a plurality of PET detectors, a flat-panel x-ray detector disposed in contact with the PET detectors and a read-out driver mounted at a rear end of the PET detectors and electrically connected with the flat-panel x-ray detector.

Abstract: Positron emission tomography (PET) systems suitable for use with dirty (positron+prompt gamma) emitters are provided. One or more prompt gamma detectors are added to the PET system, where the prompt gamma detectors are responsive to the prompt gammas provided by the dirty emitter, but are not responsive to 511 keV annihilation photons. The prompt gamma detectors can surround the imaging PET detector array and/or be disposed as end caps relative to a generally cylindrical PET detector array. The prompt gamma detectors need not provide spatial resolution, because coincidence events in the PET detector array are classified as 2-photon or 3-photon events depending on whether or not there is a time-coincident signal from the prompt gamma detectors. One application of this approach is dual isotope PET where distinct tracers labeled with clean and dirty positron emitters are simultaneously imaged.

Abstract: According to one embodiment, a radiation diagnostic apparatus includes a photon-counting detector, a counting information storage unit, an image reconstituting unit, and a controlling unit. The detector performs counting on light derived from incident radiation. The counting information storage unit stores therein counting information based on the counting result of the detector. The image reconstituting unit reconstitutes a medical image by performing a back projection process on projection data that is generated by use of the counting information stored in the counting information storage unit. After the reconstitution of the medical image, the controlling unit performs control so that all or part of the counting information is maintained in the counting information storage unit.

Abstract: A method is disclosed for determining radiation attenuation as a result of an object in a positron emission tomography scanner. In at least one embodiment, a phantom object is arranged in the positron emission tomography scanner during the method. First raw radiation data of the phantom object is acquired while the object is not arranged in the positron emission tomography scanner. A first image of the phantom object is calculated from the first raw radiation data. The object then is arranged in the positron emission tomography scanner (2) and preliminary radiation attenuation of the object is identified. Second raw radiation data of the phantom object is acquired while the object is arranged in the positron emission tomography scanner. A second image of the phantom object is calculated from the second raw radiation data taking into account the preliminary radiation attenuation. The radiation attenuation is determined on the basis of the first image and the second image.

Abstract: A timing circuit that includes a first serializer/deserializer (SERDES) configured to receive a parallel rate clock signal and a system clock start signal from an imaging system and generate a first output, a second SERDES configured to receive a stop signal that is based on an output from the medical imaging system and generate a second output, and a timestamp calculator configured to utilize the first and second outputs to generate a timestamp. A medical imaging system and a method of operating a timing circuit are also described.

Abstract: Methods and systems for signal communication in gamma ray detectors are provided. One gamma ray detector includes a scintillator block having a plurality of scintillator crystals and a plurality of light sensors coupled to the scintillator crystals and having a plurality of microcells. Each of the plurality of light sensors has a first set of signal traces connected to the microcells and a second set of signal traces connected along the first set of signal traces and together forming a signal path to a summing signal trace. Each of the plurality of light sensors also has a pin-out connected to the summing signal trace.

Abstract: To simultaneously image a plurality types of tracer molecules for a Compton image and a PET image. Provided is an imaging device comprising: a first Compton camera (10) for receiving one gamma ray emitted from an imaging target (900) administered by first probe having positron emitting nuclei and second probe having gamma ray emission nuclei; and a second Compton camera (20) which is arranged opposite to the first Compton camera (10) and receives another gamma ray emitted from the imaging target (900). The imaging device is also provided with: an imaging processor for distinguishing and reconstructing a PET image and a Compton image in accordance with the combination of the Compton cameras which detected the gamma rays; and a display for displaying the PET image and the Compton image in association respectively with the first and the second probes.

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: Methods and systems for gain calibration of a gamma ray detector are provided. One method includes measuring signals generated by one or more light sensors of a gamma ray detector, generating one or more derived curves using the measured signals as a function of bias voltage and identifying a transition point in the one or more derived curves. The method also includes determining a breakdown voltage of the one or more light sensors using the identified transition point and setting a bias of the one or more light sensors based on the determined breakdown voltage.

Abstract: According to one embodiment, a nuclear medicine diagnosis includes a light signal generating unit, photodetection unit, measurement unit, calculation unit, and storage unit. The light signal generating unit repeatedly generates light signals. The photodetection unit repeatedly generates first output signals corresponding to intensities of the light signals, repeatedly generates second output signals corresponding to intensities of gamma rays emitted from a subject. The measurement unit repeatedly measures light signal detection times and repeatedly measures gamma ray detection times. The calculation unit calculates a difference between a target gamma ray detection time and a target light signal detection time of the light signal detection times for each of the gamma ray detection times. The target light signal detection time is measured before the target gamma ray detection time. The storage unit stores the calculated difference in association with a target second output signal of the second output signals.

Abstract: A method and system for nuclear imaging normally involves detection of energy by producing bursts of photons in response to interactions involving incident gamma radiation. The detector sensitivity is increased by as much as two orders of magnitude, so that some excess sensitivity can be exchanged to achieve unprecedented spatial resolution and contrast-to-noise (C/N) ratio comparable to those in CT and MRI. Misplaced pileup events due to scattered radiation are rejected for each of the central groups to reduce image blurring, thereby further improving image quality. The reduction in detector thickness minimizes depth-of-interaction (DOI) blurring as well as blurring due to Compton-scattered radiation. The spatial sampling of the detector can be further increased using fiber optic coupling to reduce effective photodetector size. Fiber-optic coupling also enables to increase the packing fraction of PMTs to 100% by effectively removing the glass walls.

Abstract: In a PET device according to an embodiment, a first detector includes a plurality of first scintillators and detects gamma rays that are emitted from positron-emitting radionuclides that are injected into a subject. A second detector is provided on the outer circumferential side of the first detector, includes a plurality of second scintillators arranged in an arrangement surface density lower than that of the first scintillators, and detects gamma rays that have passed through the first detector. A counted information acquiring unit acquires, as first counted information and second counted information, the detection positions, energy values, and detection time regarding gamma rays detected by the first detector and the second detector.

Abstract: Various embodiments relate to a method of attenuation correction of Positron Emission Tomography (PET) data based on Magnetic Resonance Tomography (MRT) data. A method of at least one embodiment further includes determining further data being indicative of an iterative cycle of a physiological observable of a patient and matching the PET data with the MRT data based on the further data.

Abstract: A method and a transmission system are disclosed for the transmission of wanted signals between a sensor and an evaluation unit. In order to suppress interference to the sensor signals due to external interference sources as far as possible, at least one embodiment of the inventive system has at least one signal receiver with the sensor for detecting a wanted signal and a signal processing device for conditioning the wanted signal, at whose output a mixed signal with a wanted signal component and an interference signal component from at least one interference source are present; an interference source signal input for detecting at least one interference source signal of the at least one interference source; a filter device for reconstructing the interference signal component as a function of the at least one interference source signal; and a subtractor for eliminating interference superimposed on the wanted signal.

Abstract: According to one embodiment, a radiation therapy apparatus includes a radiation irradiation device, a detector included in a PET scanner, a control unit, and a PET image reconstruction unit. The radiation irradiation device emits a therapeutic radiation. The detector counts light derived from gamma rays, and is provided with a gap portion through which the therapeutic radiation passes on a plane of rotation about the body axis of a subject. The control unit controls the radiation irradiation device and the detector so as to rotate in synchronization with each other in a state capable of emitting the therapeutic radiation to the gap portion. The PET image reconstruction unit reconstructs a PET image based on position information at the time of counting of the detector that nearly coincidentally counts pair annihilation gamma rays in a state where the control unit performs rotation control.

Abstract: An apparatus comprises a plurality of radiation conversion elements (32) that convert radiation to light, and a reflector layer (34) disposed around the plurality of radiation conversion elements. The plurality of radiation conversion elements may consist of two radiation conversion elements and the reflector layer is wrapped around the two radiation conversion elements with ends (40, 42) of the reflector layer tucked between the two radiation conversion elements. The reflector layer (34) may include a light reflective layer (50) having reflectance greater than 90% disposed adjacent to the radiation conversion elements when the reflector layer (34) is disposed around the plurality of radiation conversion elements, and a light barrier layer (52).

Abstract: The present invention relates to a positron tomography imaging apparatus for a multiphase flow in an oil pipeline, which apparatus utilizes positron and electron annihilation generating a pair of coincidence gamma-rays of 511 keV energy as tomography imaging means and provides an on-line tomography imaging function for metering a multiphase flow in an oil pipeline of an oil field. The apparatus comprises a plurality of sets of parallel high-precision gamma-ray detector arrays with a particular space structure arrangement, a positron radioactive source and a shield, and can acquire a phase fraction of such multiphase flow mixture as oil, gas and water under a condition of a single radioactive source by combining an image processing function. The design of a plurality of sets of high-precision detector arrays also greatly improves accuracy of a multiphase flow metering and its applicability in multiphase flows of different flow patterns.

Abstract: A plurality of detector rings in which detectors arranged densely or spatially in a ring shape or in a polygonal shape are arranged, with an open space kept in the body axis direction, coincidences are measured for some of or all of detector pairs connecting the detector rings apart from the open space to perform three-dimensional image reconstruction, thereby imaging the open space between the detector rings as a tomographic image. Therefore, the open space is secured, with the deteriorated quality of an image suppressed, thus making it possible to easily gain access to a patient under PET scanning from outside a gantry and also provide irradiation of particle beams for cancer treatment as well as X-ray CT scanning.

Abstract: An apparatus includes a diagnostic scanner (102) and a treatment planner (112). The treatment planner (112) plans a treatment to be applied to an object. A treatment device (114) treats the object according to the treatment plan. A treatment scanner (108) scans the object during a treatment session. A motion modeler (116) uses information from the treatment scan to model a motion of the object. A motion compensated quantitative data generator (1004) uses data from the diagnostic (102) or other scanner, as well as feature geometry (1008) and feature motion (1006) information, to generate motion compensated quantitative data indicative of a feature of the object.

Abstract: Embodiments of the invention provide a high energy photon detector. A first scintillation crystal is provided. A first plurality of photosensors is on a first face of the first scintillation crystal, wherein the first plurality is at least two. A second scintillation crystal is provided. A second plurality of photosensors is on a first face of the second scintillation crystal, wherein the second plurality is at least two. An optical coupling interface is between a second face of the first scintillation crystal and a second face of the second scintillation crystal, wherein the optical coupling interface provides an optical transmission between the first scintillation crystal and the second scintillation crystal, so that the distribution of scintillation light created in one crystal is allowed to spread into the second crystal.

Abstract: The point spread function of a multi-channel collimator is modeled in photon imaging. The geometric aperture used in the point spread function is expanded to account for penetration, scattering, and/or imperfections of the collimator. The aperture is broadened using a weight that is a function of the distance of the source from the collimator. Rather than scaling the point spread function itself, the geometric aperture used in the point spread function is scaled to an effective aperture. The distance and geometric constraints may be used to determine the geometric aperture, but an additional broadening occurs as a function of the distance to account for non-ideal photon paths of travel. This additional broadening may improve the fidelity with respect to measured data relative to purely geometric or Gaussian models.

Abstract: An emission tomography device includes emission detectors for detecting a gamma ray incident from a patient body as a pulse signal, and a data collecting device for collecting information in which the gamma ray is detected in an emission detector. The data collecting device includes a timing circuit for outputting timing information corresponding to the timing of occurrence of an event in which a gamma ray is detected as a pulse signal in an emission detector, a simultaneous count circuit for identifying timing information in a true simultaneous count by comparing a plurality of timing information sent from a plurality of timing circuits, and a pulse calculating portion calculating a gamma ray detection location and a gamma ray energy from an intensity value of a pulse signal corresponding to the timing information identified by the simultaneous count circuit as a true simultaneous count.

Abstract: The technical solution as put forth by the present invention comprises a computer imaging system and detectors arranged around the detected object for collecting gamma photons from positron annihilation events. The key is a multi-pinhole plate placed between the detected object and the detectors, and the multi-pinhole plate can be a coded aperture mask coded by using a function h(x,y). The gamma photons generated from the annihilation events inside the detected object are absorbed by the detector after being collimated by the multi-pinhole plate. Accordingly, after the detectors have performed detection at multiple angles, the result is transmitted to the computer imaging system, and quasi three-dimensional images are generated after being processed by the disclosed algorithm. Furthermore, the quasi three-dimensional images generate secondary projection images and, after adjustment, generate sinograms, and finally three-dimensional tomographic images are reconstructed from multiple sinograms.

Abstract: When calculating a system matrix (detection probability), adjustment is made by fitting a point spread function (PSF) expressed by a Gauss function to a profile of count values of radiation with respect to a distance from a point source which emits radiation of the same type as the positron-emitting drug, and a distance range of the above PSF is adjusted for each layer in a depth direction of gamma-ray detectors indicating an incident direction in which the radiation strikes. By calculating the system matrix (detection probability) after adjusting the distance range of the function for each layer, improvement can be made in image quality of a reconstructed image.

Abstract: Radiation tomography apparatus of this invention has a shield that shields entering of radiation flying from outside of the gantry. The shield is formed of shielding pieces. Consequently, there is no need for manufacturing the shield in a large and expensive furnace. Accordingly, the radiation tomography apparatus may be provided that is easily manufactured and achieves suppressed cost. Moreover, with the radiation tomography apparatus of this invention, maintenance may be performed through removal of the shielding pieces without removing the entire shield.

Abstract: In beam monitoring for detecting annihilation radiations produced by radiation irradiation in radiation therapy for cancer which is performed by irradiating the affected area by X-rays, gamma rays, or particle beams, a detector-shift type combined radiation therapy/PET apparatus is provided with an open PET device that includes a plurality of shiftable multi-ring detector rings; and a radiation irradiation device that is capable of irradiation with a radiation beam through between the detector rings. The apparatus changes the positions of the detector rings, performs irradiation with the radiation beam through between the detector rings, and then performs radiation measurement.

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: A radiation detector made of High Purity Germanium (HPGe) has been specially machined to be this invented multilayer Inter-Coaxial configuration. With this special configuration, extra large volume HPGe detectors of diameters to be 6 inches, 9 inches, and even 12 inches, can be produced with current achievable HPGe crystal purity and quality, in which the entire detector crystal will be depleted and properly over biased for effective photo-induced signal collection with just less than 5000V bias applied. This invention makes extra large efficiency of 200%, 300%, and maybe even higher than 500% possible with HPGe gamma ray detectors with reasonable great resolution performances procurable based on current HPGe crystal supply capability. The invention could also be applied to any other kind of semiconductor materials if any of them could be purified enough for this application in the future.

Abstract: A Positron Emission Tomography (PET) detector assembly includes a cold plate having a first side and an opposite second side, the cold plate being fabricated from a thermally conductive and electrically non-conductive material, a plurality of PET detector units coupled to the first side of the cold plate, and a readout electronics section coupled to the second side of the cold plate. A radio frequency (RF) body coil assembly and a dual-modality imaging system are also described herein.

Abstract: A method for generating an image is provided. The method comprises: acquiring a first set of image data using a first imaging modality; sorting the first set of image data into a plurality of gates to generate a plurality of gated data sets; reconstructing each gated data set to generate a respective gated image for each gated data set; registering the respective gated images to generate a plurality of registered images; and generating a median image from the plurality of registered images, wherein each voxel of the median image is a respective median value of the corresponding voxels of the plurality of registered images.

Abstract: A gamma ray detection system includes a plurality of detector modules having a same length, where each detector module is configured to detect gamma rays generated from positron annihilation events. A first detector module of the plurality of detector modules is shifted by a predetermined distance in an axial direction from a second detector module of the plurality of detector modules that is adjacent to the first detector module, where the predetermined distance is less than the length of the detector modules.

Abstract: In a nuclear medicine imaging apparatus as a medical image diagnosis apparatus according to one embodiment, a PET detector is configured to detect a gamma ray emitted from a nuclide introduced into a body of a subject. A PET image reconstruction unit is configured to reconstruct a nuclear medicine image (PET image) as a medical image from the gamma ray projection data created based on the gamma ray detected by the PET detector using successive approximation. A controller is configured to control the PET image reconstruction unit to change the parameter used in the successive approximation depending on information regarding the scanning region in the body of the subject.

Abstract: A scintillating module is provided which includes a first scintillating layer including a plurality of scintillators extending in a first direction; a second scintillating layer including a plurality of scintillators extending in a second direction and stacked in a third direction with respect to the first scintillating layer, wherein the first, second and third directions are orthogonal to each other.

Abstract: A method and system for determining timing recovery information in a positron emission tomography (PET) system. One method includes determining energy information from pairs of light sensors of detectors of the TOF PET system, determining timing information from the pairs of light sensors of the detectors of the TOF PET system and calculating timing recovery information using the determined energy and timing information.

Abstract: An imaging system comprises: a magnetic resonance scanner (30) having a cylindrical bore (36) defining a cylinder axis (DA), the magnetic resonance scanner having a gradient coil (10, 10?) defining an isocenter (64) within the bore and an isoplane (66) passing through the isocenter and oriented transverse to the cylinder axis; a ring of radiation detectors (60a, 60b, 60?) arranged concentric with the cylindrical bore and configured to detect radiation emanating from within the bore; and a generally annular electronic circuit board (62, 62?) arranged concentric with the cylindrical bore and centered on the isoplane, the generally annular electronic circuit board operatively connected with the ring of radiation detectors to generate electrical signals indicative of detection of radiation by the ring of radiation detectors.

Abstract: Systems and methods for attenuation compensation in nuclear medicine imaging based on emission data are provided. One method includes acquiring emission data at a plurality of energy windows for a person having administered thereto a radiopharmaceutical comprising at least one radioactive isotope. The method also includes performing a preliminary reconstruction of the acquired emission data to create one or more preliminary images of a peak energy window and a scatter energy window and determining a body outline of the person from at least one of the reconstructed preliminary image of the peak energy window or of the scatter energy window. The method further includes identifying a heart contour and segmenting at least the left lung. The method additionally includes defining an attenuation map based on the body outline and segmented left lung and reconstructing an image of a region of interest of the person using an iterative joint estimation reconstruction.

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: When calibrating a positron emission tomography (PET) scanner, a radioactive calibration phantom is scanned over a period of several half lives to acquire a plurality of frames of scan data. Interlaced timing windows are employed to facilitate acquiring coincidence data for a plurality of coincidence timing windows and energy windows during a single calibration scan. Coincident events are binned according to each of a plurality of selected coincidence windows, and the PET scanner is calibrated for each of the plurality of coincidence timing windows using data acquired from the single calibration scan.

Abstract: An imaging system includes positron emission tomography (PET) detectors (30) shrouded by broadband galvanic isolation (99) and coincidence detection electronics (50, 50ob), or other radiation detectors. A magnetic resonance scanner includes a main magnet (12, 14) and magnetic field gradient assembly (20, 20?, 22, 24) configured to acquire imaging data from a magnetic resonance examination region at least partially overlapping the examination region surrounded by the PET detectors. A radio frequency coil (80, 100) has plurality of conductors (66, 166) and a radio frequency screen (88, 188, 188EB, 188F) substantially surrounding the conductors to shield the coil at the magnetic resonance frequency. The radiation detectors are outside of the radio frequency screen. Magnetic resonance-compatible radiation collimators or shielding (60, 62) containing an electrically non-conductive and non-ferromagnetic heavy atom oxide material are disposed with the radiation detectors.

Abstract: The invention relates to a system and method for enhancing image data obtained from a positron emission tomography (PET) scan. In various embodiments, the method comprises transforming an original image data set to provide a first modified image data set by performing a masked volume-wise principal component analysis (MVW-PCA) on the original image data set. The first modified image data set is then transformed to provide a second modified image data set by performing a masked volume-wise independent component analysis (MVW-ICA) on the first modified image data set, the second modified image data set thereby comprising enhanced image data.

Abstract: Multiplexing for radiation imaging is provided by using optical delay combiners to provide distinct optical encoding for each detector channel. Each detector head provides an optical output which is encoded. The encoded optical signals can be optically combined to provide a single optical output for all of the detectors in the system. This single optical output can be coupled to a fast photodetector (e.g., a streak camera). The pulse readout from the photodetector can decode the arrival time of the event, the energy of the event, and which channels registered the detection event. Preferably, the detector heads provide coherent optical outputs, and the optical delay combiners are preferably implemented using photonic crystal technology to provide photonic integrated circuits including many delay combiners.

Abstract: An X-ray detection device including a scintillator configured to convert gamma rays or X-rays into optical radiation, an optical image intensifier configured to intensify the optical radiation to generate intensified optical radiation, an optical coupling system configured to guide the intensified optical radiation, and a solid state detector configured to detect the intensified optical radiation to generate an interaction image representing an X-ray energy emission and to perform photon counting based on data of the interaction image.

Abstract: A method of correcting a timing signal that represents an arrival time of a photon at a positron emission tomography (PET) detector includes receiving a timing signal that represents an arrival time of a photon at a PET detector, receiving an energy signal indicative of an energy of the photon, calculating a timing correction using the energy signal, modifying the timing signal using the timing correction, and generating an image of an object using the modified timing signal. A system and non-transitory computer readable medium are also described herein.

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: Systems and methods for determining fluid mobility in rock samples using time-lapse position emission particle tracking (PEPT). The systems and methods use PEPT to determine permeability in rock samples, such as shale, that have a permeability of less than one micro-darcy by recording gamma-ray emissions from a tag using a positron emission tomography camera as the tag traverses with a fluid through the pores in the rock sample.

Abstract: An imaging system, including (1) a CT scanner configured to scan an object arranged on a patient pallet; (2) a PET scanner, including a first detector portion, including first detector elements, arranged circumferentially around the patient pallet, the first detector portion having a predetermined axial extent and transaxially subtending less than 360 degrees with respect to a central axis of the scanner; and a second detector portion, including second detector elements, arranged separately from and opposing the first detector portion, wherein the second detector elements are of a different type than the first detector elements, and the second detector portion is configured to be movable radially and circumferentially around the object; and (3) an acquisition subsystem configured to acquire first event data from the first detector portion and to acquire second event data from the second detector portion.

Abstract: Present embodiments relate to the calibration of detectors having one or more arrays of pixelated detectors. According to an embodiment, a method includes detecting optical outputs generated by a plurality of scintillation crystals of a detector with an array of pixelated detectors, generating, with the array of pixelated detectors, respective signals indicative of the optical outputs, generating, from the respective signals, a unique energy spectrum correlated to each of the plurality of scintillation crystals, grouping subsets of the plurality of scintillation crystals into macrocrystals, determining a representative energy spectrum peak for each macrocrystal based on the respective energy spectra of the scintillation crystals in the macrocrystal, comparing a value of the representative energy spectrum peak for each macrocrystal with a target peak value, and adjusting an operating parameter of at least one pixelated detector in the array of pixelated detectors as a result of the comparison.