Patents by Inventor Kent C. Burr

Kent C. Burr has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20220252746
    Abstract: In a gamma-ray detector system, such as a PET detector, coincidence events between multiple detector elements can be caused by inter-detector scattering and/or energy escape of the multi-stage radiation background in the scintillator crystals. Because these types of coincidence events are more likely to happen between nearby elements, they can be measured, analyzed and ultimately used to identify arrangement errors of detector elements in a gamma-ray detector system.
    Type: Application
    Filed: February 5, 2021
    Publication date: August 11, 2022
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Kent C. BURR, Yi QIANG, Xiaoli LI
  • Patent number: 11367227
    Abstract: A method of imaging includes obtaining projection data for an object representing an intensity of radiation detected along a plurality of rays through the object, obtaining an outline of the object via a secondary imaging system, the secondary imaging system using non-ionizing radiation, determining, based on the outline, a model and model parameters for the object, calculating, based on the model and the model parameters, a volumetric attenuation map for the object, and reconstructing, based on the projection data and the volumetric attenuation map, an attenuation-corrected volumetric image.
    Type: Grant
    Filed: July 28, 2020
    Date of Patent: June 21, 2022
    Assignee: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Karthikayan Balakrishnan, Kent C. Burr
  • Publication number: 20220076439
    Abstract: Optical sensors and optical markers are placed on components in a medical system to provide calibration and alignment, such as on a patient transportation mechanism and spatially separated medical diagnostic devices. Image processing circuitry uses the data captured by these optical devices to coordinate their movements and/or position. This enables scans that were captured in multiple medical diagnostic devices to be accurately aligned.
    Type: Application
    Filed: September 9, 2020
    Publication date: March 10, 2022
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Karthikayan BALAKRISHNAN, Kent C. BURR
  • Patent number: 11255985
    Abstract: A method and apparatus are provided for positron emission imaging to calibrate energy measurements of a pixilated gamma-ray detector using energy calibration based on a calibration with a distribution energy signature (i.e., having more spectral features than just a single full-energy peak). The energy calibration can be performed using a deep learning (DL) network or a physics-based model. Using the DL network, a calibration spectrum is applied to either generate the measured-signal values of known energy values (e.g., spectral peaks for spectra of various radioactive isotopes) or the parameters of an energy-calibration function/model.
    Type: Grant
    Filed: January 9, 2020
    Date of Patent: February 22, 2022
    Assignee: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Kent C. Burr, Xiaoli Li
  • Publication number: 20220036607
    Abstract: A method of imaging includes obtaining projection data for an object representing an intensity of radiation detected along a plurality of rays through the object, obtaining an outline of the object via a secondary imaging system, the secondary imaging system using non-ionizing radiation, determining, based on the outline, a model and model parameters for the object, calculating, based on the model and the model parameters, a volumetric attenuation map for the object, and reconstructing, based on the projection data and the volumetric attenuation map, an attenuation-corrected volumetric image.
    Type: Application
    Filed: July 28, 2020
    Publication date: February 3, 2022
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Karthikayan BALAKRISHNAN, Kent C. Burr
  • Publication number: 20210247530
    Abstract: A method and apparatus are provided for nonlinear energy correction of a gamma-ray detector using a calibration spectrum acquired from the background radiation of lutetium isotope 176 (Lu-176) present in scintillators in the gamma-ray detector. Further, by periodically acquiring Lu-176 spectra using the background radiation from the scintillators, the nonlinear energy correction can be monitored to detect when changes in the gamma-ray detector cause the detector to go out of calibration, and then use a newly acquired Lu-176 spectrum to update the calibration of the nonlinear energy correction as needed. The detector calibration is performed by comparing a reference histogram to a calibration histogram generated using the nonlinear energy correction, and adjusting the parameters of the nonlinear energy correction until the two histograms match.
    Type: Application
    Filed: February 12, 2020
    Publication date: August 12, 2021
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Xiaoli LI, Yi QIANG, Kent C. BURR
  • Publication number: 20210199823
    Abstract: A method and system for providing improved timing calibration information for use with apparatuses performing Time of Flight Positron Emission Tomography scans. Relative timing offset, including timing walk, within a set of processing units in the scanner are obtained and corrected using a stationary limited extent positron-emitting source, and timing offset between the set of processing units is calibrated using an internal radiation source, for performing calibration.
    Type: Application
    Filed: June 22, 2020
    Publication date: July 1, 2021
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Xiaoli LI, Yi QIANG, Kent C. BURR, Peng PENG
  • Patent number: 10962662
    Abstract: A method and apparatus are provided for positron emission imaging to calibrate timing of a pixelated gamma detector using multi-channel events. The apparatus can include processing circuitry configured to obtain calibration data representing a time and a position at which gamma rays are detected at a plurality of detector elements, and determine which gamma-ray detections of the calibration data correspond to multi-channel detections in which energy of a respective gamma ray is shared and detected by two or more of the plurality of detector elements. Additionally, the processing circuitry can be configured to determine a timing calibration of the plurality of detector elements by optimizing an objective representing agreement between time data of the multi-channel detections in the calibration data and the timing calibration.
    Type: Grant
    Filed: December 6, 2018
    Date of Patent: March 30, 2021
    Assignee: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Yi Qiang, Xiaoli Li, Kent C. Burr
  • Publication number: 20200379133
    Abstract: A method and apparatus are provided for positron emission imaging to calibrate energy measurements of a pixilated gamma-ray detector using energy calibration based on a calibration with a distribution energy signature (i.e., having more spectral features than just a single full-energy peak). The energy calibration can be performed using a deep learning (DL) network or a physics-based model. Using the DL network, a calibration spectrum is applied to either generate the measured-signal values of known energy values (e.g., spectral peaks for spectra of various radioactive isotopes) or the parameters of an energy-calibration function/model.
    Type: Application
    Filed: January 9, 2020
    Publication date: December 3, 2020
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Kent C. BURR, Xiaoli LI
  • Patent number: 10782429
    Abstract: A method and apparatus are provided for positron emission imaging to calibrate energy measurements of a pixilated gamma-ray detector using energy sharing events between channels of the detector. Due to conservation of energy, when the energy of a single gamma ray shared among multiple channels, the sum of measured energies across the respective channel must equal the original energy of the incident gamma ray. Further, the fractions of the original energy distributed to the respective channels can span the entire range of zero to the original energy. Thus, a single gamma-ray source (e.g., cesium isotope 137) can be used to continuously calibrate the nonlinear energy response of the detector over an entire range of interest.
    Type: Grant
    Filed: February 6, 2019
    Date of Patent: September 22, 2020
    Assignee: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Yi Qiang, Xiaoli Li, Kent C. Burr
  • Patent number: 10768318
    Abstract: A method and apparatus are provided for positron emission imaging to correct a recorded energy of a detected gamma ray, when the gamma ray is scattered during detection. When scattering occurs, the energy of a single gamma ray can be distributed across multiple detector elements—a multi-channel detection. Nonlinearities in the detection process and charge/light sharing among adjacent channels can result in the summed energies from the multiple crystals of a multi-channel detection deviating from the energy that would be measured in single-channel detection absent scattering. This deviation is corrected by applying one or more correction factors (e.g., multiplicative or additive) that shifts the summed energies of multi-channel detections to agree with a known predefined energy (e.g., 511 keV). The correction factors can be stored in a look-up-table that is segmented to accommodate variations in the multi-channel energy shift based on the level of energy sharing.
    Type: Grant
    Filed: October 17, 2018
    Date of Patent: September 8, 2020
    Assignee: Canon Medical Systems Corporation
    Inventors: Yi Qiang, Huini Du, Kent C. Burr
  • Publication number: 20200249369
    Abstract: A method and apparatus are provided for positron emission imaging to calibrate energy measurements of a pixilated gamma-ray detector using energy sharing events between channels of the detector. Due to conservation of energy, when the energy of a single gamma ray shared among multiple channels, the sum of measured energies across the respective channel must equal the original energy of the incident gamma ray. Further, the fractions of the original energy distributed to the respective channels can span the entire range of zero to the original energy. Thus, a single gamma-ray source (e.g., cesium isotope 137) can be used to continuously calibrate the nonlinear energy response of the detector over an entire range of interest.
    Type: Application
    Filed: February 6, 2019
    Publication date: August 6, 2020
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Yi QIANG, Xiaoli LI, Kent C. BURR
  • Publication number: 20200183025
    Abstract: A method and apparatus are provided for positron emission imaging to calibrate timing of a pixelated gamma detector using multi-channel events. The apparatus can include processing circuitry configured to obtain calibration data representing a time and a position at which gamma rays are detected at a plurality of detector elements, and determine which gamma-ray detections of the calibration data correspond to multi-channel detections in which energy of a respective gamma ray is shared and detected by two or more of the plurality of detector elements. Additionally, the processing circuitry can be configured to determine a timing calibration of the plurality of detector elements by optimizing an objective representing agreement between time data of the multi-channel detections in the calibration data and the timing calibration.
    Type: Application
    Filed: December 6, 2018
    Publication date: June 11, 2020
    Applicant: CANON MEDICAL SYSTEMS CORPORATION
    Inventors: Yi Qiang, Xiaoli Li, Kent C. Burr
  • Publication number: 20200124750
    Abstract: A method and apparatus are provided for positron emission imaging to correct a recorded energy of a detected gamma ray, when the gamma ray is scattered during detection. When scattering occurs, the energy of a single gamma ray can be distributed across multiple detector elements—a multi-channel detection. Nonlinearities in the detection process and charge/light sharing among adjacent channels can result in the summed energies from the multiple crystals of a multi-channel detection deviating from the energy that would be measured in single-channel detection absent scattering. This deviation is corrected by applying one or more correction factors (e.g., multiplicative or additive) that shifts the summed energies of multi-channel detections to agree with a known predefined energy (e.g., 511 keV). The correction factors can be stored in a look-up-table that is segmented to accommodate variations in the multi-channel energy shift based on the level of energy sharing.
    Type: Application
    Filed: October 17, 2018
    Publication date: April 23, 2020
    Applicant: Canon Medical Systems Corporation
    Inventors: Yi QIANG, Huini Du, Kent C Burr
  • Patent number: 9696434
    Abstract: An apparatus and method for testing scintillator arrays, e.g., crystal arrays for PET imaging. The apparatus includes, a two-sided tray arranged to hold scintillator arrays in either side and slide the arrays into a light-tight box having a radiation source beneath the arrays and photomultiplier tubes (PMTs) above the arrays. When arranged in the testing position with the arrays interposed between the radiation source and the PMTs, ambient light from outside the box is prevented from leaking into the box and high-voltage power is supplied to the PMTs. Otherwise, to prevent PMT damage, the high-voltage is off. The radiation source is an arrangement of sealed low-activity pieces of radioactive elements, thus minimizing requirements for radiation shielding and minimizing safety risks. The method calculates a flood map from scintillation data/counts and performs analysis according to predefined criteria, e.g., the peak-to-valley ratio, to flag arrays exhibiting inferior quality.
    Type: Grant
    Filed: June 4, 2015
    Date of Patent: July 4, 2017
    Assignee: TOSHIBA MEDICAL SYSTEMS CORPORATION
    Inventors: Kent C. Burr, Zhengyan Wang, Madhuri Kaul
  • Publication number: 20160356895
    Abstract: An apparatus and method for testing scintillator arrays, e.g., crystal arrays for PET imaging. The apparatus includes, a two-sided tray arranged to hold scintillator arrays in either side and slide the arrays into a light-tight box having a radiation source beneath the arrays and photomultiplier tubes (PMTs) above the arrays. When arranged in the testing position with the arrays interposed between the radiation source and the PMTs, ambient light from outside the box is prevented from leaking into the box and high-voltage power is supplied to the PMTs. Otherwise, to prevent PMT damage, the high-voltage is off. The radiation source is an arrangement of sealed low-activity pieces of radioactive elements, thus minimizing requirements for radiation shielding and minimizing safety risks. The method calculates a flood map from scintillation data/counts and performs analysis according to predefined criteria, e.g., the peak-to-valley ratio, to flag arrays exhibiting inferior quality.
    Type: Application
    Filed: June 4, 2015
    Publication date: December 8, 2016
    Applicant: TOSHIBA MEDICAL SYSTEMS CORPORATION
    Inventors: Kent C. BURR, Zhengyan Wang, Madhuri Kaul
  • Patent number: 9423510
    Abstract: A radiation detector for a radiation imaging system, wherein the detector comprises photosensors, arranged to receive light emitted from an array of scintillator elements. The scintillator elements absorb radiation, such as gamma rays, and emit light. Using Anger arithmetic and crystal decoding, the position of each scintillation event is determined from the relative fractions of light detected by each of the photosensors. Selectively shaping the top surface, i.e., the surface closest to the photosensors, of each scintillator element in the array, the direction of light emission from each scintillator element can be optimized such that the fraction of light detected by each photosensor is optimally distinct for each position in the array of scintillator elements. The top surface of at least one of the scintillator element array is not parallel with the bottom surface of at least one of the scintillator.
    Type: Grant
    Filed: May 15, 2014
    Date of Patent: August 23, 2016
    Assignee: TOSHIBA MEDICAL SYSTEMS CORPORATION
    Inventors: Jerry Yanqi Wang, Kent C. Burr
  • Publication number: 20150331119
    Abstract: A radiation detector for a radiation imaging system, wherein the detector comprises photosensors, arranged to receive light emitted from an array of scintillator elements. The scintillator elements absorb radiation, such as gamma rays, and emit light. Using Anger arithmetic and crystal decoding, the position of each scintillation event is determined from the relative fractions of light detected by each of the photosensors. Selectively shaping the top surface, i.e., the surface closest to the photosensors, of each scintillator element in the array, the direction of light emission from each scintillator element can be optimized such that the fraction of light detected by each photosensor is optimally distinct for each position in the array of scintillator elements. The top surface of at least one of the scintillator element array is not parallel with the bottom surface of at least one of the scintillator.
    Type: Application
    Filed: May 15, 2014
    Publication date: November 19, 2015
    Applicants: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventors: Jerry Yanqi WANG, Kent C. Burr
  • Patent number: 9140805
    Abstract: A method of arranging detector modules within a gamma ray detector apparatus, each detector module including an array of scintillation crystals to convert light into electrical signals, the light being generated in response to incident gamma rays generated by an annihilation event, the method including obtaining performance information of each of the detector modules, and determining a relative location for each of the detector modules within the gamma ray detector based on the obtained performance information of the detector modules.
    Type: Grant
    Filed: October 22, 2012
    Date of Patent: September 22, 2015
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MEDICAL SYSTEMS CORPORATION
    Inventors: Gin Chung Wang, Kent C. Burr, Huini Du, Jerry Wang
  • Patent number: 8907291
    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.
    Type: Grant
    Filed: December 13, 2013
    Date of Patent: December 9, 2014
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventors: Kent C. Burr, Daniel Gagnon, Zhengyan Wang