DYNAMIC SAMPLE MAPPING NONINVASIVE ANALYZER APPARATUS AND METHOD OF USE THEREOF

• US 20150018646A1
• Filed: 07/12/2013
• Published: 01/15/2015
• Est. Priority Date: 07/12/2013
• Status: Abandoned Application

• Current Assignee: Zyomed Corp.
• Original Assignee: Zyomed Corp.
• Inventors: Gulati, Sandeep, George, Thomas, Ruchti, Timothy, Abul-Haj, Alan, Hazen, Kevin H.
• Application Number:
  US13/941,411
• Publication Number:
  US 20150018646A1
• Time in Patent Office: Days
• US Class Current: 600/322
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/1079 using optical or photographic means
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• 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 5/6801 specially adapted to be attached to or worn on the body surface
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01N 2021/4742 comprising optical fibres
• CPC Class Codes: G01N 2021/4747 Concentric bundles
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 2201/0826 Fibre array at source, distributing

Abstract

A noninvasive analyzer apparatus and method of use thereof is described using a sample mapping phase to establish one or more analyzer/software parameters used in a subsequent individual and/or group specific data collection phase. For example, in the sample mapping phase distance between incident and collected light is varied as a function of time for collected noninvasive spectra. Spectra collected in the sample mapping phase are analyzed to determine a physiological property of the subject, such as dermal thickness, hydration, collagen density, epidermal thickness, and/or subcutaneous fat depth. Using the physiological property or measure thereof, the analyzer is optically reconfigured for the individual to yield subsequent spectra having enhanced features for noninvasive analyte property determination. Similarly, in the mapping and/or collection phase, the incident light is varied in time in terms of any of: sample probe position, incident light solid angle, incident light angle, depth of focus, energy, and/or intensity.

Claims

1. A method for determining a concentration of a blood borne analyte of a subject, comprising the steps of:

collecting a plurality of mapping spectra of the subject using a noninvasive analyzer setup in a first set of optical configurations;

calculating a metric related to skin tissue physiology of the subject using the mapping spectra;

based on the metric, setting up said analyzer in a second set of optical configurations, the first set of optical configurations configured to deliver light to the subject in a manner different than the second set of optical configurations;

collecting subject specific noninvasive spectra of the subject using the second set of optical configurations; and

post-processing the subject specific noninvasive spectra to determine the concentration.

2. The method of claim 1, wherein said step of collecting a plurality of mapping spectra comprises the step of:

tilting an optic of said analyzer to at least three orientations and collecting the mapping spectra sequentially at each of the at least three orientations of the optic.

3. The method of claim 1, wherein said step of collecting a plurality of mapping spectra comprises the step of:

sequentially collecting a set of spectra using at least three different mean radial distances between incident light from said analyzer entering skin of the subject and a detection zone of detected light exiting the skin of the subject to a detector system of said analyzer, wherein the three different mean radial distances differ from each other by at least ten micrometers, wherein the three mean radial distances are each less than one millimeter.

4. The method of claim 1, wherein said step of collecting a plurality of mapping spectra comprises the step of:

sequentially collecting a set of spectra using at least three different mean radial distances between incident light from said analyzer entering skin of the subject and a detection zone of detected light exiting the skin of the subject to a detector system of said analyzer, wherein the three different mean radial distances differ from each other by at least one-fifth of a millimeter, wherein the three mean radial distances are each less than four millimeters.

5. The method of claim 4, wherein said step of calculating a metric related to skin tissue physiology comprises any of the steps of:

generating an epidermal thickness measure of the skin tissue physiology;

generating a dermis thickness measure of the skin tissue physiology; and

generating a subcutaneous fat depth measure of the skin tissue physiology.

6. The method of claim 4, wherein said step of calculating a metric related to skin tissue physiology comprises any of the steps of:

calculating a measure of pathlength through an aqueous medium;

calculating a measure of pathlength through a fat medium; and

calculating a measure of signal-to-noise ratio for any of the set of spectra at the at least three different mean radial distances.

7. The method of claim 4, wherein said step of setting up said analyzer in the second set of optical configurations increases mean absorbance of spectra with any of:

(1) a range of 1325 to 1375 nm, (2) a range of 1375 to 1425 nm, (3) a range of 1425 to 1475, and (4) a range of 1475 to 1525 nanometers by at least ten percent relative to absorbance collected using the first set of optical configurations.

8. The method of claim 4, wherein said step of setting up said analyzer in the second set of optical configurations increases an average absorbance ratio of spectra at 1450 nanometers to that at 1720 nanometers relative to the mapping spectra using the first set of optical configurations.

9. The method of claim 4, wherein a mean range of radial distance between the incident light entering the skin and the collected light exiting the skin is greater for said plurality of mapping spectra than for the subject specific noninvasive spectra.

10. The method of claim 1, wherein the plurality of mapping spectra comprise spectra collected in more optical configurations of said analyzer than used to collect the subject specific noninvasive spectra.

11. The method of claim 1, said step of post-processing further comprising the step of:

determining correlation between two non-overlapping wavelength ranges of the subject specific noninvasive spectra.

12. The method of claim 1, said step of post-processing further comprising the steps of:

defining finite width channels for the noninvasive spectra;

calculating coherence between the channels to form a set of cross-coherence values; and

selecting a subset of the set of cross-coherence values for subsequent multivariate analysis.

13. The method of claim 1, said step of post-processing further comprising the step of:

generating a N×

N grid of at least one spectrum of the subject specific noninvasive spectra, symmetrical about a diagonal of the N×

N grid, wherein elements of the N×

N grid represent a coherence estimate versus frequency, wherein N comprises a positive integer of at least ten.

14. The method of claim 1, further comprising the step of:

using a model and said metric in said step of setting up said analyzer.

15. An apparatus for determining a concentration of a blood borne analyte of a subject, comprising:

a noninvasive analyzer, comprising;

a source configured to provide photons;

a photon transport system configured to deliver the photons to the subject; and

a detector system configured to receive the photons from the subject,

said analyzer configured to collect a plurality of mapping spectra of the subject using said analyzer in a first set of optical configurations; and

a data processing system, said data processing system configured to;

calculate a metric related to skin tissue physiology of the subject using the mapping spectra; and

set up said analyzer in a second set of optical configurations, the first set of optical configurations configured to deliver light to the subject in a manner different than the second set of optical configurations,

said analyzer configured to collect subject specific noninvasive spectra of the subject using the second optical configuration, and

said data processing system configured to post-process the subject specific noninvasive spectra to determine the concentration.

16. The apparatus of claim 15, said analyzer further comprising:

a tiltable optic, said tiltable optic configured in at least three distinct orientations during collection of the mapping spectra.

17. The apparatus of claim 15, said analyzer further comprising:

means for sequentially collecting a set of spectra using at least three different mean radial distances between incident light from said source entering skin of the subject and a detection zone of detected light exiting the skin of the subject to said detector system, wherein the three different mean radial distances differ from each other by at least one-half millimeter, wherein the three mean radial distances are each less than four millimeters.

18. The apparatus of claim 15, said analyzer comprising:

a set of at least three fiber optics at at least three radial positions from a mean position of photons exiting the subject into said detector system; and

a photon delivery system configured to individually and sequentially illuminate each of said set of at least three fiber optics with the photons from said source.

19. The apparatus of claim 15, said photon transport system comprising:

at least one optic configured to deliver a mean path of the photons to the subject at at least three positions separated from each other by at least one-twentieth of a millimeter as a function of time.

20. The apparatus of claim 15, said photon transport system comprising:

at least one optic configurable to at least three focal lengths as a function of time.

21. The apparatus of claim 15, said analyzer further comprising:

a time resolved gating system configured to detect the photons in a pulse mode from the source in time periods greater than one femtosecond and less than one hundred milliseconds after the photons leave the source.

22. The apparatus of claim 15, said photon transport system comprising:

at least one optic configurable to deliver the photons to the subject, during a single sampling period of less than one minute, at at least three mean incident angles relative to a plane normal to the subject, wherein the at least three mean incident angles differ from each other by greater than five degrees as a function of time.

23. The apparatus of claim 15, said data processing system configured to:

calculate a set of coherence values between finite width channels of elements of the noninvasive spectra; and

use said set of coherence values in determination of the concentration of the blood borne analyte of the subject.