Patents by Inventor Lei Xing

Lei Xing 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: 20150343241
    Abstract: A method of electronic portal imaging (EPID) for radiation dosimetric measurement and quality assurance (QA) in radiation therapy is provided that includes imaging a calibration photon beam and a treatment beam using an EPID imager disposed between a plastic water build-up phantom and a plastic water back-scatter phantom that is thicker than the plastic water build-up phantom, correcting the EPID images using an off-axis correction map that takes into account a horn-shape of a photon fluence profile, deconvolving the corrected EPID images using a Monte Carlo simulated EPID response kernel, the deconvolved corrected EPID images provide a primary photon fluence map, reconstructing a relative dose map using the primary photon fluence map convolving with a Monte Carlo simulated pencil-beam dose distribution kernel, and generating an absolute dose map using cross calibration to a 10x10 cm2 square field that is compared with a planned dose distribution for QA analysis.
    Type: Application
    Filed: January 13, 2014
    Publication date: December 3, 2015
    Inventors: Bin Han, Lei Xing
  • Patent number: 9200306
    Abstract: The present invention relates to a method for production and purification of polypeptides. In particular, the present invention relates to a fusion protein comprising a solubility-enhancing peptide tag moiety, a self-aggregating peptide moiety and a moiety of target peptide and to a method for production and purification of target peptides through expressing said fusion protein.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: December 1, 2015
    Assignee: TSINGHUA UNIVERSITY
    Inventors: Zhanglin Lin, Wanghui Xu, Lei Xing, Lingli Zeng, Bihong Zhou, Qing Zhao, Wei Wu
  • Publication number: 20150265851
    Abstract: An inverse planning method that is capable of controlling the appearance of the implanted fiducial(s) in segmented IMRT fields for cine MV or combined MV/kV image-guided IMRT is provided. The method for radiation treatment includes computing a radiation treatment plan and delivering beams to a target in accordance with the radiation treatment plan, where computing the radiation treatment plan includes introducing a penalty in an inverse planning objective function optimization calculation to discourage or avoid blockage of one or more fiducials in optimized multi-leaf collimator (MLC) apertures.
    Type: Application
    Filed: March 2, 2011
    Publication date: September 24, 2015
    Inventors: Yunzhi Ma, Paul J. Keall, Lei Xing
  • Patent number: 8989469
    Abstract: A method of acquiring scatter data and image projection data in computed tomography is provided that includes attenuating a radiation source using a pattern of blockers arranged to provide blocked and unblocked regions of the radiation source, and acquiring image data and scatter data of a target using an imaging device. A scatter map in the projection image can be estimated by interpolation and/or extrapolation of the projection image using an appropriately programmed computer, subtracting the estimated scatter map from the projection image to obtain scatter-corrected projections, reconstructing a CBCT volume using a total variation regularization algorithm, and applying an iterative regularization process to suppress the noise level on the reconstructed CBCT volume.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: March 24, 2015
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Benjamin Pooya Fahimian, Lei Xing, Bowen Meng
  • Publication number: 20140330064
    Abstract: A method of radiation therapy planning and delivery is provided that includes introducing a demand metric, using a volumetric modulation arc therapy system, to select a spatially optimized and non-uniform set of station or control points to be used for intensity modulation, where the set of station or control points are uniform or non-uniform, and selecting a set of control points at different gantry angles, using the volumetric modulated arc therapy system, and using the demand metric to prioritize which station or control point receives intensity modulation, where the volumetric modulated arc therapy system is differentially boosted at selected angles by inserting additional segments to the station, where the inserted additional apertures dosimetrically boost desired regions in a planning target volume to improve planning target volume coverage in a single arc rotation while sparing sensitive structures.
    Type: Application
    Filed: May 2, 2014
    Publication date: November 6, 2014
    Inventors: Lei Xing, Ruijiang Li
  • Patent number: 8849373
    Abstract: A method and system are disclosed for estimating internal position information of a target in real-time based on a single gantry-mounted x-ray imager and a respiratory signal. The x-ray imaging is done periodically to limit radiation dosage. Initial parameters for the estimation model are determined in a pre-treatment session using four dimensional computed tomography (4D CT) in combination with a respiratory signal acquired from the patient. The model parameters are updated during treatment based on the periodic x-ray image data and the respiratory signal.
    Type: Grant
    Filed: May 12, 2008
    Date of Patent: September 30, 2014
    Assignee: Stanford University
    Inventors: Paul J. Keall, Amit Sawant, Peter Maxim, Yelin Suh, Lei Xing, Billy W. Loo, Jr., Byung Chul Cho
  • Publication number: 20140242600
    Abstract: A radioluminescence microscopy system and method for imaging the distribution of radiolabeled molecules in live cell cultures and tissue sections. Cells are grown and incubated with radiolabeled molecules on a scintillator plate or a scintillator plate is placed adjacent to the cells after incubation. Scintillation light produced by decay of radiolabeled molecules inside, bound to, or surrounding the cells, is recorded on an imaging device. Fluorescence microscopy of the same cells with other types of molecules of interest that are labeled with different fluorophores can be conducted concurrently and the biological activity of the labeled molecules can be correlated.
    Type: Application
    Filed: June 8, 2012
    Publication date: August 28, 2014
    Applicant: THE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIVERSITY
    Inventors: Lei Xing, Colin Carpenter, Peter Olcott, Guillem Pratx, Conroy Sun
  • Publication number: 20140106399
    Abstract: The present invention relates to a method for production and purification of polypeptides. In particular, the present invention relates to a fusion protein comprising a solubility-enhancing peptide tag moiety, a self-aggregating peptide moiety and a moiety of target peptide and to a method for production and purification of target peptides through expressing said fusion protein.
    Type: Application
    Filed: March 15, 2013
    Publication date: April 17, 2014
    Inventors: Zhanglin LIN, Wanghui XU, Lei XING, Lingli ZENG, Bihong ZHOU, Qing ZHAO, Wei WU
  • Publication number: 20140043871
    Abstract: A circuit for providing damping in an electromagnetic interference (EMI) filter with an inductor-capacitor (LC) circuit, includes at least one capacitor connected to receive a common-mode current from the LC circuit; a current sensor that senses the common-mode current; a linear amplifier that amplifies the sensed common-mode current; and a power amplifier that receives the amplified sensed common-mode current and outputs a voltage which creates a damping impedance for frequencies of the common-mode current less than a threshold frequency and absorbs the common-mode current for frequencies greater than the threshold frequency.
    Type: Application
    Filed: August 7, 2012
    Publication date: February 13, 2014
    Applicant: Hamilton Sundstrand Corporation
    Inventors: Miaosen Shen, Ming Li, Lei Xing
  • Patent number: 8498465
    Abstract: A binary image reconstruction method is provided to identify metal objects in a computer tomography (CT) image. The method includes providing a suitably programmed computer, providing a CT image, where the CT image includes intensity data, and the suitably programmed computer is used to determine a first range of attenuation coefficient values and a second range of attenuation coefficient values in the intensity data, where when a difference between the first range of attenuation coefficient values and the second range of attenuation coefficient values is less than a pre-determined gradient threshold value, a boundary of a metal object in the CT image is determined.
    Type: Grant
    Filed: September 23, 2010
    Date of Patent: July 30, 2013
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Lei Xing, Jing Wang
  • Publication number: 20130142310
    Abstract: Embodiments of the present invention provide methods for improved radiation treatment and imaging of solid cancers utilizing radiation beam trajectory optimization techniques to obtain conformal radiation coverage of tissue that is targeted to receive radiation, while minimizing exposure of healthy tissue and organs to harmful, unnecessary radiation.
    Type: Application
    Filed: June 6, 2012
    Publication date: June 6, 2013
    Applicant: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Benjamin Pooya Fahimian, Lei Xing, Sarah Geneser, Dimitre Hristov
  • Patent number: 8331531
    Abstract: The present invention provides a radiotherapy treatment apparatus that includes a treatment beam, a magnetic field disposed parallel collinear to the treatment beam, and a target that is disposed along the treatment beam. The treatment beam can be a charged particle beam, a proton beam, an electron beam, or a linear accelerator (Linac) beam. The magnetic field is from a magnetic resonance imager (MRI), a megavolt x-ray imager, or a kilovolt x-ray imager and is disposed to operate in coordination with operation of the treatment beam and to narrow the beam. The tumor is disposed to rotate with respect to the treatment beam and the magnetic field, or the treatment beam and the magnetic field are disposed to rotate up to 360° with respect to the target when mounted to a ring gantry. The apparatus can include a rotation angle dependent shim disposed to account for Earth's magnetic field.
    Type: Grant
    Filed: March 15, 2010
    Date of Patent: December 11, 2012
    Assignees: The Board of Trustees of the Leland Stanford Junior University, The Regents of the University of California
    Inventors: Rebecca Fahrig, Norbert J. Pelc, Kim Pauly, Greig C. Scott, Amit Sawant, Paul J. Keall, Lei Xing, Steven M. Conolly
  • Publication number: 20120292534
    Abstract: A multi-phase radiation therapy treatment method is provided that includes computational software to simultaneously optimize radiation plans for each phase of delivery. A specific realization of multi-phase therapy, dual gating, is described where the first radiation therapy treatment plan provides treatment during an inhale phase of a patient breathing cycle and the second radiation therapy treatment plan provides treatment during an exhale phase of the patient breathing cycle. Using a radiation therapy machine, the first radiation therapy treatment plan is delivered during the inhale phase and the second radiation therapy treatment plan is delivered during the exhale phase of the patient breathing cycle. An associated imaging method is provided for gated volumetric image guidance at multiple different phases in a single imaging acquisition.
    Type: Application
    Filed: May 18, 2012
    Publication date: November 22, 2012
    Inventors: Sarah Geneser, Benjamin Pooya Fahimian, Lei Xing
  • Patent number: 8315357
    Abstract: A method of reducing a total number of beam segments in a dose distribution for a radiation therapy field is provided.
    Type: Grant
    Filed: October 6, 2010
    Date of Patent: November 20, 2012
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Lei Zhu, Lei Xing
  • Publication number: 20120207370
    Abstract: A method of acquiring scatter data and image projection data in computed tomography is provided that includes attenuating a radiation source using a pattern of blockers arranged to provide blocked and unblocked regions of the radiation source, and acquiring image data and scatter data of a target using an imaging device. A scatter map in the projection image can be estimated by interpolation and/or extrapolation of the projection image using an appropriately programmed computer, subtracting the estimated scatter map from the projection image to obtain scatter-corrected projections, reconstructing a CBCT volume using a total variation regularization algorithm, and applying an iterative regularization process to suppress the noise level on the reconstructed CBCT volume.
    Type: Application
    Filed: December 20, 2011
    Publication date: August 16, 2012
    Inventors: BENJAMIN Pooya FAHIMIAN, Lei Xing, Bowen Meng
  • Patent number: 8229070
    Abstract: An adaptive imaging method of monitoring intrafraction target motion during radiation therapy is provided that includes using a simultaneous Mega-Voltage (MV) imaging process and Kilo-Voltage (KV) imaging process to determine an initial 3D target position. 2D target position is monitored using the MV imaging process during a radiation therapy treatment delivery, and is in combination with an online-updated characterization of target motion that are disposed to estimate if the target has moved beyond a 3D threshold distance. The simultaneous MV imaging and KV imaging processes are for accurately determining a new 3D target position for intrafraction motion compensation and for further 2D imaging by the MV imaging process, where another simultaneous MV and KV imaging process is initiated when the target has potentially moved beyond the threshold distance as measured by the MV imaging process. The intrafraction target motion monitoring is achieved at the cost of ultralow patient imaging dose.
    Type: Grant
    Filed: September 22, 2010
    Date of Patent: July 24, 2012
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Wu Liu, Lei Xing, Gary Luxton
  • Patent number: 8144829
    Abstract: A general imaging scheme is proposed for applications of CBCT. The approach provides a superior CBCT image quality by effective scatter correction and noise reduction. Specifically, in its implementation of CBCT imaging for radiation therapy, the proposed approach achieves an accurate patient setup using a partially blocked CBCT with a significantly reduced radiation dose. The image quality improvement due to the proposed scatter correction and noise reduction also makes CBCT-based dose calculation a viable solution to adaptive treatment planning.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: March 27, 2012
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Lei Zhu, Lei Xing
  • Patent number: 8121368
    Abstract: A medical imaging-based system and method uses both kV and MV images captured during a treatment period for organ motion tracking. 3D geometric locations of internal features are computationally tracked as a function of time from internal features, such as natural biological features or implanted fiducials, which are computationally extracted from the captured kV and MV images. A partial information method allows 3D tracking to be maintained in the event that imaging information is temporarily not available.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: February 21, 2012
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Rodney D. Wiersma, Lei Xing, Weihua Mao
  • Publication number: 20110250128
    Abstract: A method of characterizing a tissue sample is provided that includes injecting a tissue sample with radiotracers, where the radiotracers include beta-emitter radio tracers, the beta-emitter radio tracers emit beta particles according to a decay of the beta-emitter radio tracers, and measuring the beta particles or Cherenkov radiation from the beta particles in the tissue sample, and determining a condition of the radio tracers in the tissue sample according to the measured beta particles or the measured Cherenkov radiation, where the determined condition includes a depth and/or a concentration of the radiotracers in the tissue sample.
    Type: Application
    Filed: April 12, 2011
    Publication date: October 13, 2011
    Inventors: Colin M Carpenter, Lei Xing, Conroy Ghin Chee Sun, Guillem Pratx
  • Publication number: 20110251484
    Abstract: Molecular imaging of radioluminescent nanoparticle probes injected into biological tissue is performed by irradiated the tissue with ionizing radiation to induce radioluminescence at optical wavelengths, preferably at predetermined near infrared wavelengths. The optical light is detected and processed to determine a spatial distribution of the probes. The radioluminescent nanoparticles may be inorganic or organic phosphors, scintillators, or quantum dots. Imaging systems realizing this technique include tomographic systems using an x-ray beam to sequentially irradiate selected regions, systems with a radioactive source producing the ionizing radiation from outside the tissue, such as with a beam, or inside the tissue, such as with an endoscope or injected radiopharmaceutical.
    Type: Application
    Filed: April 8, 2011
    Publication date: October 13, 2011
    Inventors: Colin M. Carpenter, Lei Xing, Guillem Pratx, Conroy Ghin Chee Sun