DEVICES FOR DETERMINING THE RELATIVE SPATIAL CHANGE IN SUBSURFACE RESISTIVITIES ACROSS FREQUENCIES IN TISSUE

• US 20140148721A1
• Filed: 02/03/2014
• Published: 05/29/2014
• Est. Priority Date: 12/14/2011
• Status: Abandoned Application

• Current Assignee: ImpediMed Limited
• Original Assignee: Eniko Srivastava, Paul J. Erlinger
• Inventors: ERLINGER, Paul J., CHETHAM, Scott M., DE LIMON, Alfonso L., SRIVASTAVA, Eniko
• Application Number:
  US14/171,499
• Publication Number:
  US 20140148721A1
• Time in Patent Office: Days
• US Class Current: 600/529
• CPC Class Codes: A61B 2562/0215 Silver or silver chloride containing
• CPC Class Codes: A61B 2562/04 Arrangements of multiple sensors of the same type
• CPC Class Codes: A61B 2562/043 in a linear array
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/4875 Hydration status, fluid retention of the body
• CPC Class Codes: A61B 5/4878 Evaluating oedema
• CPC Class Codes: A61B 5/6823 Trunk, e.g., chest, back, abdomen, hip
• CPC Class Codes: A61B 5/6833 Adhesive patches
• CPC Class Codes: A61B 5/68335 including release sheets or liners
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: A61B 5/7271 Specific aspects of physiological measurement analysis A61B5/316, A61B5/349 and A61B5/374 take precedence
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence

Abstract

Sensors for non-invasively determining tissue wetness/hydration based on relative changes in subsurface resistivities in tissue below the sensor when applied to a human body across different frequencies. A sensor including arrays of current-injecting and voltage-sensing electrodes may be placed on a subject'"'"'s back to determine lung wetness. Sensors may be used as part of a systems and method for determining tissue water content, systems and methods for determining lung wetness, or the like. Sensors for determining relative changes in subsurface resistivities across frequencies and systems include arrays of electrodes used to determine relative changes in subsurface resistivities across frequencies may include pairs of current-injecting and voltage sensing electrodes.

Claims

1. A device for non-invasively determining lung wetness, the device comprising:

a sensor comprising a plurality of electrodes, wherein the plurality of electrodes in the active region are configured to form a plurality of pairs of current-injecting electrodes and a plurality of pairs of voltage detection electrodes;

a signal generator configured to apply a first drive signal comprising a first frequency and a second drive signal comprising a second frequency, wherein the first and second drive signals are applied to a first pair of electrodes of the sensor;

a processor configured to receive a first recorded signal correlating to the first frequency and a second recorded signal corrected to the second frequency, wherein the first and second recorded signals are received on a second pair of electrodes of the sensor; and

wherein the processor is further configured to determine lung wetness by operating on the first and second recorded signals independently of the patient'"'"'s body geometry.