Patents by Inventor Sardar Ansari

Sardar Ansari 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: 11779235
    Abstract: Devices and techniques for continuously monitoring pressure and simultaneously monitoring changes in blood flow, vascular resistance, and/or vascular behavior are provided. The techniques are employed in measuring intracranial pressure (ICP), while simultaneously measuring cerebral blood flow and/or cerebrovascular resistance or behavior. A sensor device includes an optical and piezoelectric sensing assembly integrated into a deployable ICP monitoring device.
    Type: Grant
    Filed: February 18, 2020
    Date of Patent: October 10, 2023
    Assignee: REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Kevin R. Ward, Kenn Oldham, Lu Wang, Sardar Ansari
  • Publication number: 20230157563
    Abstract: Methods and systems monitor and assess brain bioimpedance through the use of an ocular window that assesses dynamic changes in cerebral blood volume (CBV). That ocular window is implemented through an ocular bioimpedance device that, in a non-invasive manner, measures numerous different brain health indicators using the hioimpedance measurements collected through the regions around the eyes. The ocular bioimpedance device may be goggles with localized measurement electrodes that include cathodes and anodes.
    Type: Application
    Filed: October 31, 2022
    Publication date: May 25, 2023
    Inventors: Kevin Ward, Mohamad Hakam Tiba, Ashwin Belle, Sardar Ansari, Parag G. Patil
  • Patent number: 11484217
    Abstract: Methods and systems monitor and assess brain bioimpedance through the use of an ocular window that assesses dynamic changes in cerebral blood volume (CBV). That ocular window is implemented through an ocular bioimpedance device that, in a non-invasive manner, measures numerous different brain health indicators using the bioimpedance measurements collected through the regions around the eyes. The ocular bioimpedance device may be goggles with localized measurement electrodes that include cathodes and anodes.
    Type: Grant
    Filed: May 16, 2018
    Date of Patent: November 1, 2022
    Assignee: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Kevin Ward, Mohamad Hakam Tiba, Ashwin Belle, Sardar Ansari, Parag G. Patil
  • Publication number: 20220133159
    Abstract: A method for noninvasively measuring hemodynamic variables of a person includes physically configuring a sensor to measure the pulse of a person. The sensor generates a pulse waveform indicative of the pulse of the person. A processor obtains the pulse waveform from the sensor and the processor determines a reflection coefficient and reflection delay between an incident and a reflected wave, from which the processor determines the hemodynamic variables of the person from the reflection coefficient and the reflection delay.
    Type: Application
    Filed: October 29, 2021
    Publication date: May 5, 2022
    Inventors: Sardar Ansari, Kenn Oldham, Kevin R. Ward, Kayvan Najarian, Lu Wang
  • Patent number: 11172839
    Abstract: A wearable assembly has a pulse plethysmography (PPG) sensor and a piezoelectric pressure sensor and is attachable to a patient's finger or other area corresponding to a peripheral vascular region, and further includes a signal processor configured to monitor blood flow dependent measurements and pressure measurements over time, comparing these measurements to determine properties of the vascular region, such as vascular resistance of a blood vessel, vascular radius of the blood vessel, vascular stiffness of the vascular region, blood pressure, and/or cardiac vascular power. The signal processor may apply a hysteresis comparison of the sensor outputs, e.g., using an elliptical model, and in some examples may apply an extended Kalman filter for optimizing output of the vascular region properties.
    Type: Grant
    Filed: October 25, 2017
    Date of Patent: November 16, 2021
    Assignee: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Kevin R. Ward, Sardar Ansari, Lu Wang, Kayvan Najarian, Kenn Oldham
  • Publication number: 20210304855
    Abstract: A method includes receiving raw input signals, analyzing the raw signals using a trained coding architecture including an encoding layer; and displaying an output. A computing system includes a processor and a memory storing instructions that when executed by the processor, cause the computing system to receive raw input signals, analyzing the raw signals using a trained coding architecture and display an output. A non-transitory computer readable medium includes program instructions that when executed cause a computer to receive raw input signals, analyze the raw signals using a trained coding architecture and display an output.
    Type: Application
    Filed: March 25, 2021
    Publication date: September 30, 2021
    Inventors: Sardar Ansari, Christopher Elliot Gillies, Kevin R. Ward, Hamid Ghanbari
  • Publication number: 20210169362
    Abstract: Methods and systems monitor and assess brain bioimpedance through the use of an ocular window that assesses dynamic changes in cerebral blood volume (CBV). That ocular window is implemented through an ocular bioimpedance device that, in a non-invasive manner, measures numerous different brain health indicators using the bioimpedance measurements collected through the regions around the eyes. The ocular bioimpedance device may be goggles with localized measurement electrodes that include cathodes and anodes.
    Type: Application
    Filed: May 16, 2018
    Publication date: June 10, 2021
    Inventors: Kevin Ward, Mohamad Hakam Tiba, Ashwin Belle, Sardar Ansari, Parag G. Patil
  • Publication number: 20200260975
    Abstract: Devices and techniques for continuously monitoring pressure and simultaneously monitoring changes in blood flow, vascular resistance, and/or vascular behavior are provided. The techniques are employed in measuring intracranial pressure (ICP), while simultaneously measuring cerebral blood flow and/or cerebrovascular resistance or behavior. A sensor device includes an optical and piezoelectric sensing assembly integrated into a deployable ICP monitoring device.
    Type: Application
    Filed: February 18, 2020
    Publication date: August 20, 2020
    Inventors: Kevin R. Ward, Kenn Oldham, Lu Wang, Sardar Ansari
  • Patent number: 10610113
    Abstract: The invention is a passive, wearable sensor that uses a thin piezoelectric material to produce a time history of blood pressure of the patient, with signal processing algorithms to extract physiological information. The sensor consists of a piezoelectric transducer set in a polymer laminate that can be applied to the finger or wrist of the patient. During use, a combination of compressive and bending deformation in the piezoelectric layer in response to blood pressure in the finger or wrist as a voltage output. Using signal processing techniques, the raw signal is filtered and decomposed to obtain a information to form derivative signals such as blood pressure, pulse pressure, pulse pressure variability, heart rate, heart rate variability, and respiratory rate which can be very important pre-cursors in the monitoring of the patient's physiological conditions.
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: April 7, 2020
    Assignee: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Kayvan Najarian, Kenn Oldham, Daniel Slavin, Ashwin Belle, Kevin R. Ward, Sardar Ansari, Rodney C. Daniels
  • Publication number: 20200054221
    Abstract: A wearable assembly has a pulse plethysmography (PPG) sensor and a piezoelectric pressure sensor and is attachable to a patient's finger or other area corresponding to a peripheralvascular region, and further includes a signal processor configured to monitor blood flow dependent measurements and pressure measurements over time, comparing these measurements to determine properties of the vascular region, such as vascular resistance of a blood vessel, vascular radius of the blood vessel, vascular stiffness of the vascular region, blood pressure, and/or cardiac vascular power. The signal processor may apply a hysteresis comparison of the sensor outputs, e.g., using an elliptical model, and in some examples may apply an extended Kalman filter for optimizing output of the vascular region properties.
    Type: Application
    Filed: October 25, 2017
    Publication date: February 20, 2020
    Inventors: Kevin R. Ward, Sardar Ansari, Lu Wang, Kayvan Najarian, Kenn Oldham
  • Patent number: 10349896
    Abstract: The present application describes techniques to filter signals contaminated with blunt noise. Calculated filter coefficients may be applied to signals to generate filtered output signals without the blunt noise. Sets of filter coefficients may be calculated utilizing an ?-tube filter process in conjunction with an autoregressive exogenous (ARX) model. Sets of filter coefficients may be calculated in accordance with a constrained optimization algorithm using data indicative of a source of the blunt noise. When the blunt noise is modeled in accordance with the ARX model, filtered output signals are generated having amplitudes constrained to a selected Epsilon value, which may be the amplitude of a primary component of the unfiltered signal. A set of filter coefficients may be calculated by determining, from the set of filter coefficients that satisfy the constrained optimization algorithm, a solution that produces a filtered output signal having the most time-invariant frequency composition.
    Type: Grant
    Filed: December 8, 2014
    Date of Patent: July 16, 2019
    Assignee: THE REGENTS OF THE UNIVERSTIY OF MICHIGAN
    Inventors: Sardar Ansari, Kevin Ward, Kayvan Najarian
  • Patent number: 10034638
    Abstract: Techniques for motion artifact (MA) reduction in impedance plethysmography (IP) and other physiological signals are provided. The techniques limit the amplitude of MA filtered signals by imposing an “?-tube.” The techniques may include the introduction of a regularization term to ensure that the pattern of a filtered signal is similar to the pattern of the primary component of the original, unfiltered signal by maximizing the regularity of the filtered signal. The techniques may be integrated into a portable monitoring device, such as an armband, to remove MA from various diagnostic signals and to extract primary signal components for producing enhanced device performance.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: July 31, 2018
    Assignee: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Sardar Ansari, Kayvan Najarian, Kevin Ward
  • Publication number: 20160287180
    Abstract: Techniques for motion artifact (MA) reduction in impedance plethysmography (IP) and other physiological signals are provided. The techniques limit the amplitude of MA filtered signals by imposing an “?-tube.” The techniques may include the introduction of a regularization term to ensure that the pattern of a filtered signal is similar to the pattern of the primary component of the original, unfiltered signal by maximizing the regularity of the filtered signal. The techniques may be integrated into a portable monitoring device, such as an armband, to remove MA from various diagnostic signals and to extract primary signal components for producing enhanced device performance.
    Type: Application
    Filed: February 22, 2016
    Publication date: October 6, 2016
    Inventors: Sardar Ansari, Kayvan Najarian, Kevin Ward
  • Publication number: 20160249862
    Abstract: The present application describes techniques to filter signals contaminated with blunt noise. Calculated filter coefficients may be applied to signals to generate filtered output signals without the blunt noise. Sets of filter coefficients may be calculated utilizing an ?-tube filter process in conjunction with an autoregressive exogenous (ARX) model. Sets of filter coefficients may be calculated in accordance with a constrained optimization algorithm using data indicative of a source of the blunt noise. When the blunt noise is modeled in accordance with the ARX model, filtered output signals are generated having amplitudes constrained to a selected Epsilon value, which may be the amplitude of a primary component of the unfiltered signal. A set of filter coefficients may be calculated by determining, from the set of filter coefficients that satisfy the constrained optimization algorithm, a solution that produces a filtered output signal having the most time-invariant frequency composition.
    Type: Application
    Filed: December 8, 2014
    Publication date: September 1, 2016
    Inventors: Sardar Ansari, Kevin Ward, Kayvan Najarian
  • Publication number: 20150305632
    Abstract: The invention is a passive, wearable sensor that uses a thin piezoelectric material to produce a time history of blood pressure of the patient, with signal processing algorithms to extract physiological information. The sensor consists of a piezoelectric transducer set in a polymer laminate that can be applied to the finger or wrist of the patient. During use, a combination of compressive and bending deformation in the piezoelectric layer in response to blood pressure in the finger or wrist as a voltage output. Using signal processing techniques, the raw signal is filtered and decomposed to obtain a information to form derivative signals such as blood pressure, pulse pressure, pulse pressure variability, heart rate, heart rate variability, and respiratory rate which can be very important pre-cursors in the monitoring of the patient's physiological conditions.
    Type: Application
    Filed: March 31, 2015
    Publication date: October 29, 2015
    Inventors: Kayvan Najarian, Kenn Oldham, Daniel Slavin, Ashwin Belle, Kevin R. Ward, Sardar Ansari, Rodney C. Daniels