ANALYSIS OF SKIN COLORATION

• US 20140378779A1
• Filed: 06/04/2014
• Published: 12/25/2014
• Est. Priority Date: 06/19/2013
• Status: Active Grant

• Current Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Original Assignee: Zoll Medical Corporation (Asahi Kasei Corporation)
• Inventors: Freeman, Gary A., Herken, Ulrich
• Granted Patent: US 10,799,149 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 2505/01 Emergency care
• CPC Class Codes: A61B 2576/02 specially adapted for a particular organ or body part
• CPC Class Codes: A61B 5/0048 Detecting, measuring or recording by applying mechanical forces or stimuli A61B5/021, A61B5/4884 and A61B9/00 take precedence
• CPC Class Codes: A61B 5/0051 by applying vibrations
• CPC Class Codes: A61B 5/0053 by applying pressure, e.g. compression, indentation, palpation, grasping, gauging
• CPC Class Codes: A61B 5/0064 Body surface scanning
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0077 Devices for viewing the surface of the body, e.g. camera, magnifying lens
• CPC Class Codes: A61B 5/02042 Determining blood loss or bleeding, e.g. during a surgical procedure
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0836 Measuring rate of CO2 production
• CPC Class Codes: A61B 5/1032 Determining colour for diagnostic purposes measuring colour in general G01J3/46
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/483 by thermal stimulation
• CPC Class Codes: A61B 5/6805 Vests
• CPC Class Codes: A61B 5/6898 Portable consumer electronic devices, e.g. music players, telephones, tablet computers
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/7282 : Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 5/742 : using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61B 5/746 : Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: A61N 1/36014 : External stimulators, e.g. with patch electrodes external pacemakers A61N1/3625
• CPC Class Codes: A61N 1/3925 : Monitoring; Protecting

Abstract

This document relates to computer-based systems and techniques for analyzing skin coloration using spectral imaging techniques to determine a medical condition of an individual. This document further relates to providing feedback to a rescuer or other medical professional based on the colorimetric properties of the patient'"'"'s skin.

Claims

1. A computer-implemented method comprising

obtaining color information based on an intensity of light reflected primarily from the epidermis and dermal papillae of an individual'"'"'s skin;

analyzing the color information to determine the colorimetric properties of the individual'"'"'s skin;

generating, from the analysis of the colorimetric properties of the skin, a metric that provides data indicative of a medical status of the individual; and

providing, for display to a user, a visual summary including the metric.

2. The method of claim 1, wherein the colorimetric properties comprise coordinates in a color space.

3. The method of claim 2, wherein the color space comprises a color space selected from the group consisting of a Lab color space, a L*a*b* color space, and a XYZ color space.

4. The method of claim 2, wherein the color space comprises a color space having higher dimensionality than three and having associated stimulus functions.

5. The method of claim 4, wherein the color space comprises a quadrastimulus color space.

6. The method of claim 4, wherein the color space comprises a pentastimulus color space.

7. The method of claim 4, wherein the stimulus functions comprise stimulus functions configured to enhance detection of an underlying physiologic state.

8. The method of claim 7, wherein the underlying physiologic state comprises detection of NAD and NADH.

9. The method of claim 1, wherein obtaining the color information comprises obtaining the color information from a device included in a wearable device comprising a lifevest or holter-like monitoring product.

10. The method of claim 1, further comprising sensing one or more parameters including one or more of blood pressure, end tidal carbon dioxide (EtC02), and blood oxygen saturation (Sp02), wherein generating the metric comprises generating the metric based on the analyzed colorimetric properties and the one or more sensed parameters.

11. The method of claim 1, further comprising:

obtaining baseline colorimetric properties based on an intensity of light radiation reflected from the individual'"'"'s skin.

12. The method of claim 11, wherein analyzing the colorimetric properties comprises:

comparing the obtained colorimetric properties with the obtained baseline colorimetric properties to determine an amount of change between the obtained colorimetric properties and the baseline colorimetric properties;

comparing the amount of change between the obtained colorimetric properties and the baseline colorimetric properties to a threshold; and

alerting the user when the amount of change exceeds the threshold.

13. The method of claim 12, further comprising:

updating the baseline colorimetric properties upon determining that the change between the obtained colorimetric properties and the baseline colorimetric properties exceeds the threshold.

14. The method of claim 1, further comprising calculating a risk score that provides a measure of the risk of an impending acute medical event (IAME).

15. The method of claim 1, further comprising calculating a risk score that provides a measure of the risk of one or more of a cardiac arrest, syncopal episode, traumatic arrest due to such causes as internal bleeding, blunt force trauma, various causes of hypovolemia and heart attack.

16. The method of claim 14, further comprising providing a warning based on the risk score exceeding an established threshold.

17. The method of claim 1, wherein obtaining the color information comprises:

obtaining baseline colorimetric properties based on an intensity of light radiation reflected from the individual'"'"'s skin;

applying a stimulus configured to produce a change in the colorimetric properties of the individual'"'"'s skin; and

obtaining one or more additional measurements of the colorimetric properties at times selected to capture changes in the colorimetric properties of the individual'"'"'s skin based on the applied stimulus.

18. The method of claim 17, wherein analyzing the colorimetric properties comprises:

comparing the obtained colorimetric properties with the obtained baseline colorimetric properties to determine an amount of change between the obtained colorimetric properties and the baseline colorimetric properties in response to the applied stimulus.

19. The method of claim 17, wherein applying the stimulus comprises applying a pressure to the individual'"'"'s skin.

20. The method of claim 17, wherein applying the pressure to the individual'"'"'s skin comprises applying the pressure using an air filled bladder that presses against the skin then releases.

21. The method of claim 17, wherein applying the stimulus comprises providing an audio stimulus.

22. The method of claim 17, wherein applying the stimulus comprises stimulating skin with electricity.

23. The method of claim 17, wherein applying the stimulus comprises applying a stimulus configured to generate a pain sensation.

24. The method of claim 17, wherein applying the stimulus comprises providing audio signal or voice generated signal configured to elicit a response.

25. The method of claim 1, wherein obtaining the colorimetric properties comprises obtaining the colorimetric properties via a camera in a portable telephone.

26. The method of claim 1, wherein the color information comprises a spectra.

27. The method of claim 26, wherein the spectra comprises an absorption spectra for wavelengths between 500 and 600 nm.

28. The method of claim 26, wherein the spectra comprises a reflectance spectra for wavelengths between 500 and 600 nm.

29. The method of claim 1, wherein the color information comprises luminance information for each of multiple colors.

30. The method of claim 1, wherein the color information comprises luminance information for red, green and blue components collected by a charge-coupled device (CCD).

31. A system for determining information about a patient status based on colorimetric properties of the individual'"'"'s skin, the system comprising:

a colorimeter configured to obtain a color information based on an intensity of light reflected primarily from the epidermis and dermal papillae of an individual'"'"'s skin;

a processor configured to;

analyze the color information to determine the colorimetric properties of the individual'"'"'s skin;

generate, from the analysis of the colorimetric properties of the skin, a metric that provides data indicative of a medical status of the individual; and

a display device configured to display a visual summary including the metric.

32. The system of claim 31 wherein the colorimetric properties comprise coordinates in a color space.

33. The system of claim 32, wherein the color space comprises a color space selected from the group consisting of a Lab color space, a L*a*b* color space, and a XYZ color space.

34. The system of claim 32, wherein the color space comprises a color space having higher dimensionality than three and having associated stimulus functions.

35. The system of claim 34, wherein the color space comprises a quadrastimulus color space.

36. The system of claim 34, wherein the color space comprises a pentastimulus color space.

37. The system of claim 34, wherein the stimulus functions comprises stimulus functions configured to enhance detection of an underlying physiologic state.

38. The system of claim 37, wherein the underlying physiologic state comprises detection of NAD and NADH.

39. The system of claim 31, wherein the colorimeter is disposed within in a wearable device like lifevest or holter-like monitoring product

40. The system of claim 31, further comprising one or more sensors configured to measure one or more parameters including one or more of blood pressure, end tidal carbon dioxide (EtC02), and blood oxygen saturation (Sp02), wherein the processor is further configured to generate the metric based on the analyzed colorimetric properties and the one or more sensed parameters.

41. The system of claim 31, wherein the processor is further configured to cause the colorimeter to obtain a baseline colorimetric properties based on an intensity of light radiation reflected from the individual'"'"'s skin.

42. The system of claim 41, wherein the processor is further configured to analyze the colorimetric properties by:

comparing the obtained colorimetric properties with the obtained baseline colorimetric properties to determine an amount of change between the obtained colorimetric properties and the baseline colorimetric properties;

comparing the amount of change between the obtained colorimetric properties and the baseline colorimetric properties to a threshold; and

alerting the user when the amount of change exceeds the threshold.

43. The system of claim 42, wherein the processor is further configured to update the baseline colorimetric properties upon determining that the change between the obtained colorimetric properties and the baseline colorimetric properties exceeds the threshold.

44. The system of claim 31, wherein the processor is further configured to calculate a risk score that provides a measure of the risk of an impending acute medical event (IAME).

45. The system of claim 31, wherein the processor is further configured to calculate a risk score that provides a measure of the risk of one or more of a cardiac arrest, syncopal episode, traumatic arrest due to such causes as internal bleeding, blunt force trauma, various causes of hypovolemia and heart attack.

46. The system of claim 44, wherein the processor is further configured to provide a warning based on the risk score exceeding an established threshold.

47. The system of claim 31, wherein the processor is further configured to obtain the color information by:

obtaining baseline colorimetric properties based on an intensity of light radiation reflected from the individual'"'"'s skin;

applying a stimulus configured to produce a change in the colorimetric properties of the individual'"'"'s skin; and

obtaining one or more additional measurements of the colorimetric properties at times selected to capture changes in the colorimetric properties of the individual'"'"'s skin based on the applied stimulus.

48. The system of claim 31, wherein the processor is further configured to analyze the colorimetric properties by:

comparing the obtained colorimetric properties with the obtained baseline colorimetric properties to determine an amount of change between the obtained colorimetric properties and the baseline colorimetric properties in response to the applied stimulus.

49. The system of claim 31, wherein the colorimeter comprises a camera in a portable telephone.

50. The system of claim 31, wherein the color information comprises a an absorption spectra for wavelengths between 500 and 600 nm.

51. The system of claim 31, color information comprises a reflectance spectra for wavelengths between 500 and 600 nm.