Patents by Inventor Charles C. Watson

Charles C. Watson 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: 8193505
    Abstract: In positron emission tomography (PET), a detector's response to scattered radiation may be different from its response to unscattered (true coincidence) photons. This difference should be accounted for during normalization and scatter correction. The disclosure shows that only a knowledge of the ratio of the scatter to trues efficiencies is necessary, however. A system and method are disclosed for measuring the scatter/trues detection efficiency ratio, as well as for applying this compensation during the scatter correction of PET emission data. PET detector efficiencies are measured in two steps, the first using a plane radiation source, and the second using a plane radiation source in combination with a scattering medium. A ratio of the scatter and trues detection efficiency is obtained from this data for each detector/crystal, and is applied as a correction factor to PET data obtained during medical imaging processes.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: June 5, 2012
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Charles C. Watson, Larry Byars, Christian J. Michel, Harold Rothfuss
  • Patent number: 8058620
    Abstract: A method for improving clinical data quality in Positron Emission Tomography (PET). The method provides for the processing of PET data to accurately and efficiently determine a data signal-to-noise (SNR) corresponding to each individual clinical patient scan, as a function of a singles rate in a PET scanner. The method relates an injected dose to the singles rate to determine SNR(Dinj), and provides an accurate estimate of quantity proportional to SNR, similar in function to SNR(Dinj). Knowledge of SNR(Dinj) permits determination of peak SNR, optimal dose, SNR deficit, dose deficit, and differential dose benefit. The patient dose is fractionated, with a small calibration dose given initially. After a short uptake, the patient is pre-scanned to determine T, S, and R. An optimal dose is then determined and the remainder is injected.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: November 15, 2011
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Bernard Bendriem, Michael E. Casey, Charles C. Watson
  • Patent number: 8022368
    Abstract: A method for reducing randoms variance in a Positron Emission Tomograph (PET) or Positron Emission Tomograph combined with another Medical Imaging device is disclosed. An average of an element of the randoms event (delayeds) sinogram may be estimated by dividing fan sums in delayeds sinogram by singles rates taken from headers of the delayeds sinogram.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: September 20, 2011
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventor: Charles C. Watson
  • Publication number: 20110074410
    Abstract: A method and a system are disclosed for calibrating an emission tomography subsystem in a combined MR (magnetic resonance) and emission tomography imaging system. In at least one embodiment, the method includes providing a phantom that is configured such that the phantom is visible on a MR image, providing an attenuation map of the phantom, wherein the attenuation map includes an attenuation of the phantom, obtaining the MR image of the phantom, obtaining a position of the phantom from the MR image, mapping the attenuation map with the position of the phantom, and calibrating the emission tomography subsystem using the attenuation map mapped with the position of the phantom.
    Type: Application
    Filed: September 28, 2009
    Publication date: March 31, 2011
    Inventors: Ralf Ladebeck, Johannes Pauli, Charles C. Watson
  • Publication number: 20110042572
    Abstract: A method for improving clinical data quality in Positron Emission Tomography (PET). The method provides for the processing of PET data to accurately and efficiently determine a data signal-to-noise (SNR) corresponding to each individual clinical patient scan, as a function of a singles rate in a PET scanner. The method relates an injected dose to the singles rate to determine SNR(Dinj), and provides an accurate estimate of quantity proportional to SNR, similar in function to SNR(Dinj). Knowledge of SNR(Dinj) permits determination of peak SNR, optimal dose, SNR deficit, dose deficit, and differential dose benefit. The patient dose is fractionated, with a small calibration dose given initially. After a short uptake, the patient is pre-scanned to determine T, S, and R. An optimal dose is then determined and the remainder is injected.
    Type: Application
    Filed: November 2, 2010
    Publication date: February 24, 2011
    Applicant: SIEMENS MEDICAL SOLUTIONS USA, INC.
    Inventors: Bernard Bendriem, Michael E. Casey, Charles C. Watson
  • Patent number: 7894652
    Abstract: A method for correcting PET emission data for prompt gamma emission background components present in non-pure positron-emitting isotopes uses a two component fit of modeled scatter and modeled prompt gamma emission in the area of scatter tails in a normalized emission sinogram. The method allows a PET scan using non-standard PET isotopes to be quantitative and thus more clinically useful.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: February 22, 2011
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Charles H. Hayden, Jr., Michael E. Casey, Charles C. Watson
  • Patent number: 7888632
    Abstract: A method for co-registering attenuation data of MR coils in a MR/PET imaging system with PET emission data includes computing a likelihood of PET emission data on a grid in a parameter space based on an algorithm, wherein the algorithm defines L(?, ?body, ?coils{p}) as a log-likelihood of measured PET data, where ? is an emitter distribution (image), ?body is a known linear attenuation coefficient (LAC) distribution of the body from MRI, ?coils is a linear attenuation coefficient map of MRI coils, and {p} is a set of parameters governing the position of each coil, wherein if ?coils is assumed, then ? can be reconstructed and forward projected and L can be computed. The method includes adjusting the estimated position of the MR coils to maximize the likelihood of emission data based on the computed L.
    Type: Grant
    Filed: September 22, 2009
    Date of Patent: February 15, 2011
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Ralf Ladebeck, Christian J. Michel, Charles C. Watson
  • Publication number: 20110015904
    Abstract: Example embodiments are directed to a method of correcting attenuation in a magnetic resonance (MR) scanner and a positron emission tomography (PET) unit. The method includes acquiring PET sinogram data of an object within a field of view of the PET unit. The method further includes producing an attenuation map based on a maximum likelihood expectation maximization (MLEM) of a parameterized model instance and the PET sinogram data.
    Type: Application
    Filed: July 16, 2009
    Publication date: January 20, 2011
    Inventors: Matthias Fenchel, Ralf Ladebeck, Christian J. Michel, Charles C. Watson
  • Patent number: 7851763
    Abstract: A method for improving clinical data quality in Positron Emission Tomography (PET). The method provides for the processing of PET data to accurately and efficiently determine a data single-to-noise ratio (SNR) corresponding to each individual clinical patient scan, as a function of a singles rate in a PET scanner. The method relates an injected dose to the singles rate to determine SNR(Dinj),and provides an accurate estimate of a quantity proportional to SNR, similar in function to the SNR(Dinj). Knowledge of SNR(Dinj) permits determination of peak SNR, optimal dose, SNR deficit, dose deficit, and differential dose benefit. The patient dose is fractionated, with a small calibration dose given initially. After a short uptake, the patient is pre-scanned to determine T, S, and R. An optimal does is then determined and the remainder injected.
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: December 14, 2010
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Bernard Bendriem, Michael E. Casey, Charles C. Watson
  • Patent number: 7844096
    Abstract: A method and system for spatially localized, noise-adaptive smoothing of filtered back-projection (FBP) nuclear images includes smoothing a FBP image on a pixel-by-pixel basis using a shift-invariant kernel such as a Gaussian kernel. The width of the kernel may be varied on a pixel basis, such that the smoothed image contains a constant SNR over the entire image.
    Type: Grant
    Filed: January 22, 2007
    Date of Patent: November 30, 2010
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventor: Charles C Watson
  • Publication number: 20100148047
    Abstract: A method for improving clinical data quality in Positron Emission Tomography (PET). The method provides for the processing of PET data to accurately and efficiently determine a data single-to-noise ratio (SNR) corresponding to each individual clinical patient scan, as a function of a singles rate in a PET scanner. The method relates an injected dose to the singles rate to determine SNR(Dinj), and provides an accurate estimate of a quantity proportional to SNR, similar in function to the SNR(Dinj). Knowledge of SNR(Dinj) permits determination of peak SNR, optimal dose, SNR deficit, dose deficit, and differential dose benefit. The patient dose is fractionated, with a small calibration dose given initially. After a short uptake, the patient is pre-scanned to determine T, S, and R. An optimal does is then determined and the remainder injected.
    Type: Application
    Filed: November 20, 2009
    Publication date: June 17, 2010
    Applicant: Siemens Medical Solutions USA, Inc.
    Inventors: Bernard Bendriem, Michael E. Casey, Charles C. Watson
  • Patent number: 7737405
    Abstract: A method of TOF-PET image reconstruction using time-truncated TOF-PET projection data. The time-truncated TOF-PET data is obtained by narrowing the scanner time window to a smaller “time window field of view,” which reduces the field of view of a TOF-PET scanner. This results in a lower list mode stream transfer rate, which can be useful in high count rate data acquisitions, in particular 82Rb cardiac studies.
    Type: Grant
    Filed: September 17, 2008
    Date of Patent: June 15, 2010
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Charles C. Watson, Vladimir Panin, Bernard Bendriem, Michael E. Casey
  • Publication number: 20100078568
    Abstract: In positron emission tomography (PET), a detector's response to scattered radiation may be different from its response to unscattered (true coincidence) photons. This difference should be accounted for during normalization and scatter correction. The disclosure shows that only a knowledge of the ratio of the scatter to trues efficiencies is necessary, however. A system and method are disclosed for measuring the scatter/trues detection efficiency ratio, as well as for applying this compensation during the scatter correction of PET emission data. PET detector efficiencies are measured in two steps, the first using a plane radiation source, and the second using a plane radiation source in combination with a scattering medium. A ratio of the scatter and trues detection efficiency is obtained from this data for each detector/crystal, and is applied as a correction factor to PET data obtained during medical imaging processes.
    Type: Application
    Filed: September 29, 2009
    Publication date: April 1, 2010
    Applicant: Siemens Medical Solutions USA, Inc.
    Inventors: Larry Byars, Christian J. Michel, Harold Rothfuss, Charles C. Watson
  • Publication number: 20100074501
    Abstract: A method for co-registering attenuation data of MR coils in a MR/PET imaging system with PET emission data includes computing a likelihood of PET emission data on a grid in a parameter space based on an algorithm, wherein the algorithm defines L(?, ?body, ?coils{p}) as a log-likelihood of measured PET data, where ? is an emitter distribution (image), ?body is a known linear attenuation coefficient (LAC) distribution of the body from MRI, ?coils is a linear attenuation coefficient map of MRI coils, and {p} is a set of parameters governing the position of each coil, wherein if ?coils is assumed, then ? can be reconstructed and forward projected and L can be computed. The method includes adjusting the estimated position of the MR coils to maximize the likelihood of emission data based on the computed L.
    Type: Application
    Filed: September 22, 2009
    Publication date: March 25, 2010
    Applicant: SIEMENS MEDICAL SOLUTIONS USA, INC.
    Inventors: Ralf Ladebeck, Christian J. Michel, Charles C. Watson
  • Publication number: 20090072154
    Abstract: A method for reducing randoms variance in a Positron Emission Tomograph (PET) or Positron Emission Tomograph combined with another Medical Imaging device is disclosed. An average of an element of the randoms event (delayeds) sinogram may be estimated by dividing fan sums in delayeds sinogram by singles rates taken from headers of the delayeds sinogram.
    Type: Application
    Filed: May 15, 2008
    Publication date: March 19, 2009
    Applicant: Siemens Medical Solutions USA, Inc.
    Inventor: Charles C. Watson
  • Publication number: 20090072155
    Abstract: A method of TOF-PET image reconstruction using time-truncated TOF-PET projection data. The time-truncated TOF-PET data is obtained by narrowing the scanner time window to a smaller “time window field of view,” which reduces the field of view of a TOF-PET scanner. This results in a lower list mode stream transfer rate, which can be useful in high count rate data acquisitions, in particular 82Rb cardiac studies.
    Type: Application
    Filed: September 17, 2008
    Publication date: March 19, 2009
    Applicant: Siemens Medical Solutions USA, Inc.
    Inventors: Charles C. Watson, Vladimir Panin, Bernard Bendriem, Michael E. Casey
  • Publication number: 20080283758
    Abstract: A method for correcting PET emission data for prompt gamma emission background components present in non-pure positron-emitting isotopes uses a two component fit of modeled scatter and modeled prompt gamma emission in the area of scatter tails in a normalized emission sinogram. The method allows a PET scan using non-standard PET isotopes to be quantitative and thus more clinically useful.
    Type: Application
    Filed: April 28, 2008
    Publication date: November 20, 2008
    Applicant: Siemens Medical Solutions USA, Inc.
    Inventors: Charles H. Hayden, JR., Michael E. Casey, Charles C. Watson
  • Publication number: 20080175457
    Abstract: A method and system for spatially localized, noise-adaptive smoothing of filtered back-projection (FBP) nuclear images includes smoothing a FBP image on a pixel-by-pixel basis using a shift-invariant kernel such as a Gaussian kernel. The width of the kernel may be varied on a pixel basis, such that the smoothed image contains a constant SNR over the entire image.
    Type: Application
    Filed: January 22, 2007
    Publication date: July 24, 2008
    Inventor: Charles C. Watson
  • Patent number: 7397035
    Abstract: Correction of time-of-flight (TOF) PET data for scattered radiation explicitly models the TOF of the annihilation photon pairs along their individual scattered paths, yielding a distinct, accurate estimated scatter contribution for each time offset bin of the measured TOF data. This is accomplished by extending the single scatter simulation algorithm to include a new detection efficiency function ?TOF,n.
    Type: Grant
    Filed: October 16, 2006
    Date of Patent: July 8, 2008
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventor: Charles C. Watson
  • Patent number: 6429434
    Abstract: A transmission source serves to detect activity from a radiation source for correcting attenuation in either PET mode or SPECT mode. The transmission source includes a detector dedicated to collecting attenuation data in PET mode. A collimated radiation source and a detector are positioned with respect to a tomography device such that only a selected strip of the imaging detector of the tomograph is illuminated such that events unrelated to the attenuation are eliminated. The transmission source can either be a coincidence transmission source or a singles transmission source and includes a collimator in which is disposed a radiation source. An opening is defined by the collimator for exposing a selected portion of the imaging detectors of the tomograph device. Positioned behind the radiation source, relative to the imaging detectors, is the dedicated attenuation detector. In a dual head tomograph device, one transmission source of the present invention is disposed opposite each bank of imaging detectors.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: August 6, 2002
    Inventors: Charles C. Watson, Stephen D. Miller, Ronald Nutt, Michael E. Casey, James J. Hamill