Patents Assigned to Impedimed Limited
  • Patent number: 8099250
    Abstract: A method of determining parameter values used in impedance analysis of a subject. The method includes using a processing system to determine a number of impedance measurements at a corresponding number of frequencies. The impedance measurements are used to determine estimates of parameter values, with the estimates being used to determine theoretical impedance values based on the parameter value estimates. The theoretical impedance values are compared to the measured impedance values to allow a modification direction to be determined for at least one of the parameter value estimates. This is then used to modify at least one parameter value estimate, with the parameter values being determined at least in part from one or more modified parameter value estimates.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: January 17, 2012
    Assignee: Impedimed Limited
    Inventors: Tim Essex, Leigh Cordwin Ward
  • Publication number: 20110313311
    Abstract: Apparatus for use in performing impedance measurements on a subject, the apparatus including a probe having a plurality of electrodes, the probe being configured to allow at least some of the electrodes to be in contact with at least part of the subject and a processing system for, determining at least one first impedance value, measured at a site using a first electrode configuration, determining at least one second impedance value, measured at the site using a second electrode configuration and determining an indicator indicative of the presence, absence or degree of an anomaly using the first and second impedance values.
    Type: Application
    Filed: November 27, 2009
    Publication date: December 22, 2011
    Applicant: IMPEDIMED LIMITED
    Inventor: Richelle Leanne Gaw
  • Publication number: 20110301489
    Abstract: Apparatus for use in performing impedance measurements on a subject, wherein the apparatus includes a processing system for, at each of three frequencies, determining first and second parameter values for first and second impedance parameters relating to the impedance of at least one body segment of the subject, solving simultaneous equations representing a circle defined with respect to the first and second impedance parameters to thereby determine circle parameter values, the equations being solved using the first and second parameter values at each of the three frequencies, using the circle parameter values to determine a third impedance parameter value at a respective frequency and using the third impedance parameter value to determine an indicator indicative of relative fluid levels within the body segment of the subject.
    Type: Application
    Filed: November 10, 2009
    Publication date: December 8, 2011
    Applicant: IMPEDIMED LIMITED
    Inventors: Tim Essex, Leigh Cordwin Ward, Richelle Leanne Gaw
  • Publication number: 20110251513
    Abstract: A method for use in analysing impedance measurements performed on a subject, the method including, in a processing system determining at least one impedance value, representing the impedance of at least a segment of the subject, determining an indicator indicative of a subject parameter using the at least one impedance value and a reference and displaying a representation of the indicator.
    Type: Application
    Filed: May 13, 2008
    Publication date: October 13, 2011
    Applicant: IMPEDIMED LIMITED
    Inventors: Scott Chetham, Tim Essex, Brian William Ziegelaar
  • Publication number: 20110087129
    Abstract: Apparatus for performing impedance measurements on a subject. The apparatus includes a first processing system for determining an impedance measurement procedure and determining instructions corresponding to the measurement procedure. A second processing system is provided for receiving the instructions, using the instructions to generate control signals, with the control signals being used to apply one or more signals to the subject. The second processing system then receives first data indicative of the one or more signals applied to the subject, second data indicative of one or more signals measured across the subject and performs at least preliminary processing of the first and second data to thereby allow impedance values to be determined.
    Type: Application
    Filed: June 30, 2006
    Publication date: April 14, 2011
    Applicant: Impedimed Limited
    Inventors: Scott Chetham, Andrew William Ward, James Mcfarlane Kennedy
  • Publication number: 20110054343
    Abstract: A method of performing impedance measurements on a subject. The method includes using a processing system to determine at least one impedance measurement to be performed, and at one electrode arrangement associated with the determined measurement. A representation of the arrangement is displayed so the impedance measurement can be performed once the electrodes have been arranged in accordance with the displayed representation.
    Type: Application
    Filed: June 30, 2006
    Publication date: March 3, 2011
    Applicant: Impedimed Limited
    Inventors: Scott Chetham, Leigh Cordwin Ward, Tim Essex
  • Publication number: 20110046505
    Abstract: A method for use in performing impedance measurements on a subject. The method includes, in a processing system, determining at least one first impedance value, measured at a site using a first electrode configuration, determining at least one second impedance value, measured at the site using a second electrode configuration, and determining the presence, absence or degree of an anomaly using the first and second impedance values.
    Type: Application
    Filed: August 7, 2008
    Publication date: February 24, 2011
    Applicant: IMPEDIMED LIMITED
    Inventors: Bruce Herbert Cornish, Brian John Thomas, Jye Geoffrey Smith
  • Publication number: 20110025348
    Abstract: Apparatus for use in performing impedance measurements on a subject. The apparatus includes a processing system for causing a first signal to be applied to the subject, determining an indication of a second signal measured across the subject, using the indication of the second signal to determine any imbalance and if an imbalance exists, determining a modified first signal in accordance with the imbalance and causing the modified first signal to be applied to the subject to thereby allow at least one impedance measurement to be performed.
    Type: Application
    Filed: October 15, 2008
    Publication date: February 3, 2011
    Applicant: Impedimed Limited
    Inventors: Scott Chetham, Christopher Newton Daly, Ian John Bruinsma
  • Publication number: 20100168530
    Abstract: A method for determining biological indicators, the method including, in a processing system causing at least one radiation attenuation measurement to be performed and determining at least one first biological indicator using determined radiation attenuation. In addition to this, method includes causing at least one impedance measurement to be performed and determining at least one second biological indicator using a determined impedance measurement.
    Type: Application
    Filed: November 29, 2007
    Publication date: July 1, 2010
    Applicant: IMPEDIMED LIMITED
    Inventors: Scott Chetham, Christopher Newton Daly, Ian John Bruinsma
  • Publication number: 20100152605
    Abstract: A probe for use in performing impedance measurements on a subject. The probe includes a housing for being held by an operator in use, a contact surface for contacting the subject and a connector for connecting the contact surface to a measuring device.
    Type: Application
    Filed: April 17, 2008
    Publication date: June 17, 2010
    Applicant: IMPEDIMED LIMITED
    Inventor: Leigh Cordwin Ward
  • Publication number: 20100109739
    Abstract: In various embodiments, applicants' teachings are related to an active guarding circuit and method for reducing parasitic impedance signal loading on a signal-transmission channel that is shunted by a parasitic impedance. The presence of an electrical signal on the signal-transmission channel causes a leakage current to flow through the parasitic impedance. In various embodiments, the circuit comprises an amplifier and an impedance, one terminal of the impedance is coupled to the signal-transmission channel. The input of the amplifier is coupled to the signal-transmission channel and the output is coupled to the other terminal of the impedance so as to cause a compensation current to flow through the impedance. The gain of the amplifier and the value of the impedance are selected so that the compensation current has a magnitude substantially equal to the leakage current magnitude.
    Type: Application
    Filed: March 31, 2008
    Publication date: May 6, 2010
    Applicant: Impedimed Limited
    Inventors: Joel Ironstone, David Wang, Frank Zhang, Chung Shing Fan, Morrie Altmejd, Kenneth Carless Smith
  • Publication number: 20100100003
    Abstract: A method for performing impedance measurements on a subject. The method includes, in a processing system, causing at least one electrical signal to be applied to the subject via first leads operatively connected to first electrodes provided on the subject, determining a first indication indicative of at least one first electrical signal measured via second leads operatively disconnected from second electrodes positioned on the subject, determining a second indication indicative of at least one second electrical signal measured via second leads operatively connected to second electrodes positioned on the subject, and determining from the indications and the at least one applied signal, at least one instantaneous impedance value.
    Type: Application
    Filed: January 14, 2008
    Publication date: April 22, 2010
    Applicant: Impedimed Limited
    Inventors: Scott Chetham, Christopher Newton Daly, Ian John Bruinsma
  • Publication number: 20090287102
    Abstract: Impedance analysis can be used to measure calf muscle pump (CMP) function in a patient. This may be done by applying electrical signals via a first set of electrodes, and measuring the impedance via a second set of electrodes. The change in impedance as the patient undergoes calf extension or exercise may be measured, and the change in impedance may then be used to assess CMP function. The change in impedance may be used to determine an indicator indicative of the volume of blood ejected by the CMP.
    Type: Application
    Filed: February 13, 2009
    Publication date: November 19, 2009
    Applicant: Impedimed Limited
    Inventor: Leigh Cordwin Ward
  • Publication number: 20080270051
    Abstract: A method of determining parameter values used in impedance analysis of a subject. The method includes using a processing system to determine a number of impedance measurements at a corresponding number of frequencies. The impedance measurements are used to determine estimates of parameter values, with the estimates being used to determine theoretical impedance values based on the parameter value estimates. The theoretical impedance values are compared to the measured impedance values to allow a modification direction to be determined for at least one of the parameter value estimates. This is then used to modify at least one parameter value estimate, with the parameter values being determined at least in part from one or more modified parameter value estimates.
    Type: Application
    Filed: July 27, 2006
    Publication date: October 30, 2008
    Applicant: Impedimed Limited
    Inventors: Tim Essex, Leigh Cordwin Ward