Hyperspectral technology for assessing and treating diabetic foot and tissue disease

• US 20070038042A1
• Filed: 08/21/2006
• Published: 02/15/2007
• Est. Priority Date: 04/04/2005
• Status: Active Grant

• Current Assignee: Hypermed Imaging Incorporated
• Original Assignee: Hypermed Imaging Incorporated
• Inventors: Brand, Derek, Freeman, Jenny, Panasyuk, Svetlana, Schomacker, Kevin, Hopmeier, Michael
• Granted Patent: US 8,971,984 B2
• Time in Patent Office: Days
• US Class Current: 600/310
• 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 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/1036 Measuring load distribution, e.g. podologic studies
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/412 Detecting or monitoring sepsis
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: A61B 5/447 specially adapted for aiding the prevention of ulcer or pressure sore development, i.e. before the ulcer or sore has developed
• CPC Class Codes: A61B 5/4884 inducing physiological or psychological stress, e.g. applications for stress testing
• 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: A61F 2/5046 for designing or making customized prostheses, e.g. using templates, finite-element analysis or CAD-CAM techniques
• CPC Class Codes: A61F 2/583 Hands; Wrist joints
• CPC Class Codes: A61F 2/586 Fingers
• CPC Class Codes: A61F 2/60 Artificial legs or feet or parts thereof
• CPC Class Codes: A61F 2/7812 Interface cushioning members placed between the limb stump and the socket, e.g. bandages or stockings for the limb stump
• CPC Class Codes: A61F 2002/5007 having elastic means different from springs, e.g. including an elastomeric insert elastic coating A61F2002/3007; springs A61F2002/5072; plate-like springs for feet A61F2002/6657
• CPC Class Codes: A61F 2002/501 having an inflatable pocket filled with fluid, i.e. liquid or gas
• CPC Class Codes: A61F 2002/6614 Feet
• CPC Class Codes: A61F 2002/6621 : Toes
• CPC Class Codes: A61F 2002/7635 : for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/7675 : for measuring oxygen content
• CPC Class Codes: A61F 2002/7695 : Means for testing non-implantable prostheses for testing implantable prostheses A61F2240/008; for implanting artificial joints A61F2/468
• CPC Class Codes: A61F 5/0127 : for the feet A61F5/0111 takes precedence
• CPC Class Codes: A61F 5/013 : for the arms, hands or fingers A61F5/0118 takes precedence
• CPC Class Codes: G01N 2021/3144 : for oxymetry
• CPC Class Codes: G01N 2021/4709 : Backscatter
• CPC Class Codes: G01N 21/31 : Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01N 21/359 : using near infrared light
• CPC Class Codes: G01N 21/474 : Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/4795 : spatially resolved investigating of object in scattering medium in vivo A61B
• CPC Class Codes: G01N 21/49 : within a body or fluid
• CPC Class Codes: G16H 50/20 : for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/30 : for calculating health indices; for individual health risk assessment
• CPC Class Codes: G16Z 99/00 : Subject matter not provided for in other main groups of this subclass

Abstract

This invention relates generally to an index map comprising both pressure and perfusion information from a diabetic patient foot for the purpose of treatment. The index map may also be a map of perfusion and/or metabolism of the tissue (reflecting oxygen delivery and oxygen extraction, obtained by thermal imaging, hyperspectral imaging, or duplex ultrasound, MRA, CT or laser Doppler imaging. This information aids treatment in prevention of diabetic foot ulceration and amputation and in treatment of tissue compromise to prevent tissue loss in other body regions.

Claims

1. A method of ameliorating a disorder by determining a physiological state of a tissue in response to a physical stress comprising:

determining the physiological state of the tissue, wherein said tissue is not subject to the physical stress, to obtained an unstressed physiological state;

subjecting the tissue to a physical stress;

determining the physiological state of the stressed tissue to obtain a stressed physiological state; and

identifying areas of the tissue or corresponding aspects of the physical stress that can be modified to reduce the difference between the stressed and unstressed physiological states.

2. The method of claim 1, wherein determining the physiological state of the tissue, wherein said tissue is not subject to the physical stress to obtained an unstressed physiological state is determined from a control database of said physiological states.

3. The method of claim 1, comparing the stressed physiological state with the unstressed physiological state to identify areas of the tissue or corresponding aspects of the physical stress that can be modified to reduce the difference between the stressed and unstressed physiological states.

4. The method of claim 1, wherein the tissue is a toe, a foot, a leg, a finger, a hand, an arm, or any portion thereof.

5. The method of claim 1, wherein the physiological state comprises tissue oxygenation, tissue metabolism or tissue perfusion.

6. The method of claim 1, wherein the physical stress comprises pressure exerted on the tissue from a prosthetic device.

7. The method of claim 4, wherein the prosthetic device is selected from the group consisting of a toe, foot, hand, finger, leg or arm prosthesis.

8. The method of claim 1, wherein determining the physiological state is made by obtaining a hyperspectral or multispectral image of the tissue.

9. The method of claim 1 wherein determining the pressure load is made by obtaining a hyperspectral or multispectral tissue map

10. The method of claim 1, further comprising modifying the areas of the tissue or the corresponding aspects of the physical stress to reduce the difference between the stressed and unstressed physiological states.

11. The method of claim 7, wherein modification involves altering the structure of a prosthetic device, a compression stocking, a bandage or a tissue wrap.

12. The method of claim 8, wherein altering the structure of the prosthetic device comprises adding or removing cushioning material.

13. The method of claim 9, wherein the adding or removing cushioning prevents ulceration or tissue breakdown attributable to the prosthetic device.

14. A method for designing a prosthetic device comprising:

testing the device on a patient according to the method of claim 1;

and

modifying the device according to results of the testing.

15. A method for designing a prosthetic device comprising:

generating HT gradient map of the stressed verses the unstressed tissue according to the method of claim 11;

identifying areas of the tissue that are at risk for ulcer formation from said gradient map; and

designing the prosthetic devise to reduce pressure to those areas of the tissue identified to be at risk from the gradient map.

16. The method of claim 11, wherein the design reduces the risk of tissue ischemia in unbroken skin, formation of an ulcer or wound, formation of a plantar ulcer, venous stasis, venous ulcer disease or an infection.

19. The method of claim 15, wherein the HT gradient map measures oxygen saturation across the sole of the foot.

20. The method of claim 15, wherein the HT gradient map measures oxyhemoglobin across the sole of the foot.

21. The method of claim 15, wherein the HT gradient map measures deoxyhemoglobin across the sole of the foot.

22. The method of claim 15, wherein the HT gradient map represents an algorithmic combination of oxyhemoglobin and oxygenation saturation across the sole of the foot.

23. The method of claim 15, wherein at risk areas of tissue are indicated by low oxygen saturation tissue areas.

24. The method of claim 15, wherein at risk areas are indicated by tissue areas with low oxyhemoglobin.

25. The method of claim 15, wherein at risk areas are indicated by tissue areas which have an algorithmic combination of oxy and deoxyhemoglobin data.

26. The method of claim 15, further comprising redistributing pressure on the foot by tailored orthotics which reduce pressure around at risk skin areas.

27. The method of claim 23, wherein the tailored orthotics are shoe soles.

28. The method of claim 23, wherein the tailored orthotics are gels.

29. The method of claim 15, further comprising redistributing pressure to the sole of the foot to reduce pressure around at risk areas as determined when the individual is upright, walking, running or reclining.

30. The method of claim 15, further comprising redistributing pressure on the sole of the foot by tailored orthotics which reduce or eliminate pressure around at risk skin areas.

31. The method of claim 15, further comprising redistributing pressure on the tissue by a tailored device which reduce pressure around at risk areas to substantially zero.

32. The method of claim 15, further comprising redistributing pressure on the sole of the foot by tailored orthotics which reduce pressure around at risk areas to less than zero.

33. The method of claim 15, wherein the pressure is distributed on tissue of the lower extremity or elsewhere in the body by a specially tailored device which increases pressure in the skin areas around areas of venous ulceration

34. the method of claim 1, wherein the pressure is distributed on the foot by a tailored device that reduces pressure in a wound or at risk skin areas to less than zero.

35. The method of claim 1, further comprising:

generating a pressure gradient map that indicates pressures across the sole of a foot;

redistributing pressures across the sole to reduce pressure on at risk areas or high pressure areas.

36. The method of claim 1, further comprising:

generating a pressure gradient map that indicates pressures across the tissue;

redistributing pressure across the tissue to reduce pressure on at risk areas or high pressure areas.

37. The method of claim 1, further comprising identifying at risk areas by:

comparing changes in oxygenation levels of the tissue over a period of time.

38. The method of claim 1, wherein at risk areas are identified by comparing changes in oxygenation levels of the tissue when said tissue not bearing weight.

39. The method of claim 38, wherein the tissue is a foot of a patient and the weight is the body weight of the patient.

40. The method of claim 1, wherein at risk areas are identified by comparing changes in oxygenation levels of the tissue before and after exercise.

41. The method of claim 40 wherein the tissue is a foot.

42. The method of claim 40, where exercise is performed on a treadmill.

43. The method of claim 1, wherein at risk areas are identified by comparing an HT oxygenation map of the tissue to a map of oxygenation levels gathered from a large number of tissues.

44. The method of claim 1, wherein at risk areas are identified by comparing an HT oxygentation map of a foot to an HT oxygenation map of another foot.

17. A method for orthotic treatment for preventing plantar ulcer formation comprising:

generating a hyperspectral image, gradient map of the sole of a foot;

identifying areas of the sole that are at risk for ulcer formation from said gradient map;

redistributing pressure from said areas.

18. A method for orthotic treatment in preventing ulcers on the tissue of a foot or limb stump comprising:

obtaining a HT map of the tissue that combines information about pressure placed by a prosthetic device on the tissue and gravity, and adequacy of tissue oxygenation, tissue metabolism or tissue perfusion of the tissue; and

modifying the prosthetic device to maximize tissue oxygenation, tissue metabolism or tissue perfusion of the tissue.

45. An instrument which comprises:

a collector for collecting data on pressure or shear stress of a tissue;

another collector for collecting data on tissue oxygenation or perfusion;

a register for combining both sets of data into a single tissue map.

46. The instrument of claim 45, wherein the instrument further creates an orthotic, prosthetic or cushioned surface.

47. The instrument of claim 45, wherein the orthotic, prosthetic or cushioned surface created serves to protect diseased tissue or tissue at risk for disease.

48. A method for diagnosing a tissue comprising:

collecting first information on pressure or shear stress of said tissue;

collecting second information on tissue oxygenation, tissue metabolism or tissue perfusion information of said tissue; and

combining both first and second information to identify portions of said tissue that are diseased or susceptible to disease.

49. The method of claim 48, which provides information about the tissue of a patient which is then used in modifying the environment of a patient or treat disease of said tissue.

50. A method for treating a disease or disorder comprising:

combining information regarding pressure or shear stress on a tissue with tissue oxygenation, tissue metabolism or tissue perfusion information of said tissue;

identifying from the combined information portions of said tissue that are diseased or

susceptible to disease; and

modifying the environment of a patient to prevent or treat the disease or disorder.

51. The method of claim 50, further comprising:

combining the tissue information with oxygenation information of said tissue determined from hyperspectral mapping.

52. The method of claim 50, wherein modifying the environment comprises orthotic treatment.

53. The method of claim 50, wherein orthotic treatment comprises modification of a shoe sole to reduce or eliminate physical stress on said tissue.

54. The method of claim 50, wherein modifying the environment comprises prosthetic treatment.

55. The method of claim 50 wherein modifying the environment comprises applying a cushioning modification.

56. The method of claim 50 wherein the information on pressure or shear stress and oxygenation information are provided by hyperspectral imaging.

57. A method of ameliorating a disorder by determining a physiological state of a tissue comprising:

determining tissue oxygenation, tissue metabolism or tissue perfusion information of said tissue;

determining pressure or shear stress on said tissue;

identifying areas of the tissue or corresponding aspects of the physical stress that are indicative of susceptibility to disease; and

modifying an environment around said identified susceptible tissue.