APPARATUS AND METHOD FOR CONTINUOUS NONINVASIVE MEASUREMENT OF RESPIRATORY FUNCTION AND EVENTS

• US 20110060215A1
• Filed: 03/30/2010
• Published: 03/10/2011
• Est. Priority Date: 03/30/2009
• Status: Active Grant

• Current Assignee: LifeWave Biomedical, Inc.
• Original Assignee: LifeWave Biomedical, Inc.
• Inventors: Tupin, Joe Paul JR., Murray, Kenneth Arlan JR., Tupin, John David, Tupin, Joe Paul
• Granted Patent: US 9,002,427 B2
• Time in Patent Office: Days
• US Class Current: 600/425
• CPC Class Codes: A61B 2560/0412 Low-profile patch shaped housings
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/0507 using microwaves or terahertz waves
• CPC Class Codes: A61B 5/0803 Recording apparatus specially adapted therefor
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/087 Measuring breath flow
• CPC Class Codes: A61B 5/091 Measuring volume of inspired or expired gases, e.g. to determine lung capacity
• CPC Class Codes: A61B 5/1075 for measuring dimensions by non-invasive methods, e.g. for determining thickness of tissue layer A61B8/0858 takes precedence
• CPC Class Codes: A61B 5/1135 by monitoring thoracic expansion
• CPC Class Codes: A61B 5/6804 Garments; Clothes
• CPC Class Codes: A61B 5/6805 Vests
• CPC Class Codes: A61B 5/6831 Straps, bands or harnesses
• CPC Class Codes: A61B 5/6833 Adhesive patches

Abstract

An apparatus and method for non-invasive and continuous measurement of respiratory chamber volume and associated parameters including respiratory rate, respiratory rhythm, tidal volume, dielectric variability and respiratory congestion. In particular, a non-invasive apparatus and method for determining dynamic and structural physiologic data from a living subject including a change in the spatial configuration of a respiratory chamber, a lung or a lobe of a lung to determine overall respiratory health comprising an ultra wide-band radar system having at least one transmitting and receiving antenna for applying ultra wide-band radio signals to a target area of the subject'"'"'s anatomy wherein the receiving antenna collects and transmits signal returns from the target area.

Claims

1. An apparatus for determining a change in the spatial configuration of a lung by interrogating the lung with electromagnetic energy, comprising:

at least one antenna adapted to be located adjacent a portion of the lung; and

a sensing unit capable of resolving a change in reflected signals, wherein said sensing unit of the apparatus is capable of resolving a change in reflected signals that are functionally related to a change in respiratory volume.

2. An apparatus according to claim 1, wherein said apparatus is located external to the body.

3. An apparatus according to claim 1, wherein said sensing unit further comprises:

a substrate and at least two antennae mounted to said substrate in a pattern and being capable of both transmitting and receiving radiofrequency signals.

4. An apparatus according to claim 1, wherein the reflected signals are derivative of an earlier transmitted ultra wide-band signal.

5. An apparatus according to claim 1, wherein the reflected signals are derivative of an earlier transmitted ultra wide-band signal having a frequency band extending from 3.1 GHz to 10.6 GHz, ensuring compliance with applicable FCC regulations.

6. An apparatus according to claim 1, wherein the device is adapted to collect data from at least one lung.

7. An apparatus according to claim 1, wherein the apparatus is adapted to collect said data from a targeted portion of at least one lung.

8. An apparatus according to claim 7 wherein said targeted portion is any of the upper, middle or lower lobes of at least one lung and said targeted portion is encompassed by an interrogation volume and said interrogation volume encompasses a respiratory chamber.

9. A medical device for assessing pulmonary functionality, comprising:

a sensing unit including a control unit, a radar transceiver, and at least one antenna, said at least one antenna being adapted to be located adjacent a portion of a lung to measure dynamic motion of a targeted portion of the lung.

10. A medical device according to claim 9 wherein said control unit drives said radar transceiver and said radar transceiver transmits radiofrequency energy at said targeted portion and said radar transceiver receives reflections from said targeted portion and said at least one antenna couples the radiofrequency energy between said transceiver and said targeted portion.

11. A medical device according to claim 9 wherein said sensing unit further comprises software configured to cause said sensing unit to be capable of resolving a change in a spatial configuration of the lung.

12. A medical device according to claim 11 wherein said change in spatial configuration is functionally related to a change in lung volume.

13. A medical device according to claim 9, wherein said sensing unit further comprises:

a substrate;

said at least one antenna mounted to said substrate and being capable of sensing a reflected signal; and

a plurality of conductors extending from said at least one antenna and electrically coupled with said control unit.

14. A medical device, according to claim 9, wherein said sensing unit further comprises:

a substrate;

at least two antennae mounted to said substrate in a pattern and being capable of sensing reflected signals received by said at least two antennae; and

a plurality of conductors extending from said at least two antennae and electrically coupled with said sensing unit.

15. A medical device, according to claim 9, wherein said at least one antenna is adapted to be located on a subject'"'"'s chest adjacent a portion of at least one lung.

16. A medical device, according to claim 9, wherein said at least one antenna is adapted to be located in close proximity to the sternum within a three centimeter radius of a center of the sternum so as to simultaneously collect reflected signals caused by the beating of the heart and internal movement derivative of respiration.

17. A method for determining changes in respiratory volume in a body wherein an ultra wide-band medical radar transceiver, including a transmitter and a receiver and a signal processor integrated with software elements in conjunction with a central processing unit are used according to the following steps:

said transceiver transmits a series of extremely short duration electromagnetic pulses into a body,

said electromagnetic impulses encounter a boundary between different biological substances in the body,

small amounts of incident energy encountering the boundary are reflected back towards said receiver as raw reflections where said raw reflections are captured and pre-processed by said receiver,

said receiver captures a plurality of said raw reflections using a high speed sample and hold circuit where capture time for a sample of said raw reflections is set equal to a round trip time of flight from said transmitter to a depth range of interest and back to said receiver,

said plurality of sampled reflections from said depth ranges of interest are integrated to form an integrated signal to minimize high frequency noise so as to avoid corruption of desired data related to tracking instantaneous respiratory chamber volume,

said integrated signal is amplified and passed through a low-pass filter to prevent signal aliasing prior to digitization,

a predetermined number of reflections for a first range of interest are collected and integrated,

said receiver sample timing is changed and reflections from a next range of interest are captured,

said above steps are repeated until reflections from an entire range of interest across the respiratory chamber are collected,

said above step is then continually repeated to deliver an updated instantaneous measure of respiratory volumetric changes.

18. The method according to claim 17 wherein said boundaries within a target range of interest move with respect to placement of said transceiver'"'"'s antenna, producing a complex series of time-varying reflections, and wherein said complex series of time-varying reflections are continually processed by said signal processor to extract information on the mechanical activity of at least one lung.

19. The method according to according to claim 18 wherein said signal processor and central processing unit provide calculation of respiratory chamber volume via the additional steps of:

said digitized radar reflections are first range aligned on sweep boundaries and passed through a series of high pass filters to minimize low frequency noise and static clutter,

resultant data associated with all anatomical motion in said range of interest is amplified and coarse quantized using a binary quantizer where the quantizer threshold for a given sweep or row is based on the median value of the data set, resulting in an intermediate black and white image,

said intermediate image is further refined through the application of a series of one or more 1-dimensional or 2-dimensional filters to reduce noise to remove random speckle noise and increase the sharpness of the image boundary edges, supporting accurate determinate of spatial change, and,

thereby presenting an image space full of various spatial structures changing in time that represent both lung wall motion and various noise sources including organs, bones, and stray radiofrequency emissions.

20. The method according to claim 19 wherein said data is further refined via the application of at least one additional metric to delineate and confirm that the structures found in the image are lung wall excursions and not caused by unrelated signal sources.

21. The method according to claim 17 wherein said at least one additional metric is respiratory rate wherein the respiratory rate is integrated within said signal processor and is detected via application and processing of the UWBMR signals,

said signal processor calculating the respiratory rate via conversion of an entire swept image space to a predetermined frequency domain using an algorithm,

wherein said algorithm identifies and isolates an image region of the swept range containing the strongest respiratory signal,

while simultaneously determining a range of depth containing the targeted respiratory motion for use in determining one or more additional metrics.