Noninvasive physiological analysis using excitation-sensor modules and related devices and methods

• US 9,808,204 B2
• Filed: 08/03/2012
• Issued: 11/07/2017
• Est. Priority Date: 10/25/2007
• Status: Active Grant

• Current Assignee: Yukka Magic LLC
• Original Assignee: Valencell, Inc.
• Inventors: LeBoeuf, Steven Francis, Tucker, Jesse Berkley, Aumer, Michael Edward
• Primary Examiner(s): Kremer, Matthew
• Application Number:
  US13/566,269
• Publication Number:
  US 20120296184A1
• Time in Patent Office: 1,922 Days
• Field of Search: None
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 2562/046 in a matrix array
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02116 of pulse wave amplitude A61B5/02225 takes precedence
• CPC Class Codes: A61B 5/02141 Details of apparatus construction, e.g. pump units or housings therefor, cuff pressurising systems, arrangements of fluid conduits or circuits A61B5/02233, A61B5/0235 take precedence
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/6815 Ear
• CPC Class Codes: A61B 5/6838 Clamps or clips
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured

Abstract

Methods and apparatus for qualifying and quantifying excitation-dependent physiological information extracted from wearable sensors in the midst of interference from unwanted sources are provided. An organism is interrogated with at least one excitation energy, energy response signals from two or more distinct physiological regions are sensed, and these signals are processed to generate an extracted signal. The extracted signal is compared with a physiological model to qualify and/or quantify a physiological property. Additionally, important physiological information can be qualified and quantified by comparing the excitation wavelength-dependent response, measured via wearable sensors, with a physiological model.

Claims

1. A method of assessing blood pressure in an organism, the method comprising:

directing light at one or more regions of the organism via at least two optical emitters, wherein at least one optical emitter generates light at a first wavelength, wherein at least one other optical emitter generates light at a second wavelength shorter than the first wavelength, and wherein the second wavelength is in the range of blue-UV;

detecting, via an optical detector, light at the first and second wavelengths scattered from the organism and generating, via the optical detector, a first electrical signal associated with the first wavelength and a second electrical signal associated with the second wavelength; and

processing, via at least one processor, the first and second electrical signals, wherein the processing comprises;

filtering each of the first and second electrical signals with respect to skin motion noise to generate a first extracted signal associated with the first wavelength and a second extracted signal associated with the second wavelength that is distinct from the first extracted signal, wherein the first extracted signal comprises information about blood flow through a blood vessel of the organism, and wherein the second extracted signal comprises information about size of the blood vessel; and

comparing the first extracted signal and the second extracted signal, responsive to generation of each by the filtering with respect to the skin motion noise, in context of a physiological model to assess the blood pressure of the organism, wherein the comparing comprises;

calculating the blood pressure of the organism based on an area of the blood vessel and based on a volumetric flow rate of blood therein, wherein the area is based on the size of the blood vessel and a change in the size thereof indicated by the second extracted signal, and wherein the volumetric flow rate is indicated by the first extracted signal.

2. The method of claim 1, wherein the at least two optical emitters and the optical detector are integrated into a wearable device worn by the organism.

3. The method of claim 2, wherein the wearable device comprises an earpiece module.

4. The method of claim 2, wherein the wearable device comprises a telemetric device.

5. The method of claim 1, wherein the at least two optical emitters are selected from the group consisting of laser diodes (LDs), light-emitting diodes (LEDs), and organic light-emitting diodes (OLEDs).

6. The method of claim 1, wherein the at least two optical emitters, the optical detector, and the at least one processor are integrated into a wearable device worn by the organism.

7. The method of claim 1, wherein filtering each of the first and second electrical signals with respect to skin motion noise comprises:

subtracting a skin-related optical scatter signal from the first electrical signal to generate the first extracted signal containing the information about the blood flow; and

subtracting the skin-related optical scatter signal from the second electrical signal to generate the second extracted signal containing the information about the size of the blood vessel.

8. The method of claim 7, wherein the skin-related optical scatter signal is detected at a region of the organism that is proximate to the optical detector.

9. The method of claim 1, wherein filtering each of the first and second electrical signals with respect to skin motion noise comprises:

differentially amplifying a skin-related optical scatter signal relative to the first and second electrical signals.

10. The method of claim 1, wherein the light generated by the at least two optical emitters is pulsed and synchronized in time.