Please download the dossier by clicking on the dossier button x
×

Device and method for measuring blood flow in an organ

  • US 7,529,576 B2
  • Filed: 04/01/2004
  • Issued: 05/05/2009
  • Est. Priority Date: 04/05/2003
  • Status: Active Grant
First Claim
Patent Images

1. A device for measuring blood flow in an organ using an injected indicator comprising:

  • a radiation source for emitting near infrared radiation into tissue of the organ at a first location;

    a sensor for detecting a proportion of the emitted near infrared radiation that exits from the organ at a second location; and

    an evaluation unit that detects the proportion of the emitted near infrared radiation that exits from tissue of the organ as a single input signal, said evaluation unit being programmed to perform the following evaluation steps;

    (a) dividing up said single input signal into a pulsatile component and a non-pulsatile component;

    (b) determining an injected indicator concentration with reference to the organ tissue from said non-pulsatile component of said single input signal;

    (c) iteratively determining, from said non-pulsatile component, an inflow function i(t) that characterizes blood flow through the organ by incrementally varying a mean transit time mtt until a stop criterion is reached;

    (d) determining an injected indicator concentration with reference to blood volume in the organ from said pulsatile component of said single input signal and the iteratively determined inflow function i(t);

    (e) calculating a blood volume in the organ as a quotient of the injected indicator concentration with reference to the organ tissue and the injected indicator concentration with reference to the blood volume in the organ; and

    (f) calculating a blood flow in the organ as a quotient of the blood volume in the organ and the mean transit time mtt when the stop criterion has been reached.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×