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).

  • 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
  • Patent number: 8796637
    Abstract: A method and system for calibrating an imaging system in which a positron-emitting radioisotope source is arranged in or adjacent to an imaging region of the imaging system, an annihilation target is arranged at a position separated from the positron-emitting radioisotope source by a predetermined distance, coincident event pairs resulting from annihilation of positrons at the annihilation target are detected, a calibration time offset for a detector element in the imaging system is calculated based on the detected coincident event pairs, and the detector element is calibrated with the completed calibration time offset.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: August 5, 2014
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventors: Kent C. Burr, Xiaoli Li, Gin-Chung Wang, Huini Du, Daniel Gagnon
  • Publication number: 20140110589
    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: Application
    Filed: October 22, 2012
    Publication date: April 24, 2014
    Inventors: Gin Chung WANG, Kent C. BURR, Huini DU, Jerry WANG
  • Publication number: 20140103217
    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: Application
    Filed: December 13, 2013
    Publication date: April 17, 2014
    Applicants: Toshiba Medical Systems Corporation, Kabushiki Kaisha Toshiba
    Inventors: Kent C. Burr, Daniel Gagnon, Zhengyan Wang
  • Patent number: 8633444
    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: June 3, 2011
    Date of Patent: January 21, 2014
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventors: Kent C. Burr, Daniel Gagnon, Zhengyan Wang
  • Publication number: 20120305782
    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: Application
    Filed: June 3, 2011
    Publication date: December 6, 2012
    Applicants: TOSHIBA MEDICAL SYSTEMS CORPORATION, KABUSHIKI KAISHA TOSHIBA
    Inventors: Kent C. BURR, Daniel Gagnon, Zhengyan Wang
  • Patent number: 8294110
    Abstract: A system and method for determining correction factors used to determine energy of an event detected by a gamma ray detector having nonlinear photosensors arranged over a scintillation array of crystal elements, the gamma ray detector using optical multiplexing or analog electronic multiplexing. The method includes acquiring, for each nonlinear photosensor, a signal value generated by the nonlinear photosensor in response to receiving scintillation light emitted by a crystal in the array of crystal elements in response to arrival of a gamma ray; and determining a relative position of the event, the relative position being one of a predetermined number of cell locations, the predetermined number of cell locations being greater than a number of crystal elements in the array of crystal elements; and determining, for each cell location, a correction factor based on an average total signal value and a predetermined energy value of the gamma ray.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: October 23, 2012
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventor: Kent C. Burr
  • Publication number: 20120228484
    Abstract: A system and method for determining correction factors used to determine energy of an event detected by a gamma ray detector having nonlinear photosensors arranged over a scintillation array of crystal elements, the gamma ray detector using optical multiplexing or analog electronic multiplexing. The method includes acquiring, for each nonlinear photosensor, a signal value generated by the nonlinear photosensor in response to receiving scintillation light emitted by a crystal in the array of crystal elements in response to arrival of a gamma ray; and determining a relative position of the event, the relative position being one of a predetermined number of cell locations, the predetermined number of cell locations being greater than a number of crystal elements in the array of crystal elements; and determining, for each cell location, a correction factor based on an average total signal value and a predetermined energy value of the gamma ray.
    Type: Application
    Filed: March 11, 2011
    Publication date: September 13, 2012
    Applicants: TOSHIBA MEDICAL SYSTEMS CORPORATION, KABUSHIKI KAISHA TOSHIBA
    Inventor: Kent C. BURR
  • Patent number: 8080780
    Abstract: An apparatus and associated method for gamma ray detection that improves the timing resolution is provided. A crystal of interaction in a scintillation crystal array emits scintillation light in response to interaction with a gamma ray. The scintillation light is detected by one or more photomultiplier tubes. Each photomultiplier tube that detects the scintillation light detects the light at a different time. The apparatus determines the location of the gamma ray interaction and uses the location of the interaction to generate correction times for each waveform generated by the photomultiplier tubes. The waveforms are corrected with the correction timings and combined to extract a time of arrival estimate for the gamma ray. Noise thresholding is also used to select waveforms having low noise for combination to extract the time of arrival estimate.
    Type: Grant
    Filed: December 29, 2009
    Date of Patent: December 20, 2011
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Medical Systems Corporation
    Inventors: Kent C. Burr, Daniel Gagnon
  • Publication number: 20110155898
    Abstract: An apparatus and associated method for gamma ray detection that improves the timing resolution is provided. A crystal of interaction in a scintillation crystal array emits scintillation light in response to interaction with a gamma ray. The scintillation light is detected by one or more photomultiplier tubes. Each photomultiplier tube that detects the scintillation light detects the light at a different time. The apparatus determines the location of the gamma ray interaction and uses the location of the interaction to generate correction times for each waveform generated by the photomultiplier tubes. The waveforms are corrected with the correction timings and combined to extract a time of arrival estimate for the gamma ray. Noise thresholding is also used to select waveforms having low noise for combination to extract the time of arrival estimate.
    Type: Application
    Filed: December 29, 2009
    Publication date: June 30, 2011
    Applicants: Kabushiki Kaisha Toshiba, TOSHIBA MEDICAL SYSTEMS CORPORATION
    Inventors: Kent C. BURR, Daniel GAGNON