Near infrared risk assessment of diseases

• US 20050075546A1
• Filed: 09/17/2004
• Published: 04/07/2005
• Est. Priority Date: 09/19/2003
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: NIR Diagnostics Incorporated
• Inventors: MacIntyre, Duncan, Samsoondar, James, Kaushal, Ashwani
• Granted Patent: US 7,328,052 B2
• Time in Patent Office: Days
• US Class Current: 600/310
• CPC Class Codes: A61B 2562/0238 Optical sensor arrangements for performing transmission measurements on body tissue
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence

Abstract

The present invention provides an apparatus and a method for identifying the risk of a clinical condition in a human or animal by correlating Near Infrared (NIR) absorbance spectral data with one or several parameters including a concentration of one or more substances in the skin, a concentration of one or more substances in skin plus subdermal tissue, a score derived from one or more clinical tests like a stress test on a treadmill, coronary angiography, or intravascular coronary ultrasound. The method determines the concentration of a compound in the skin of a human or animal and comprises the steps of placing a part of the skin against a receptor, directing electromagnetic radiation (EMR) from the near-infrared spectrum onto the skin, measuring a quantity of EMR reflected by, or transmitted through, the skin with a detector; and performing a quantitative mathematical analysis of the quantity of EMR to determine the concentration of the compound, for example free and esterfied cholesterol. An example of a clinical condition is cardiovascular disease.

Claims

1. A method for determining the concentration of a compound in the skin of a human or animal comprising the steps of:

(a) placing a part of the skin against a receptor;

(b) directing electromagnetic radiation (EMR) from the near-infrared spectrum onto the skin;

(c) measuring a quantity of EMR reflected by, or transmitted through, the skin with a detector; and

(d) performing a quantitative mathematical analysis of the quantity of EMR to determine the concentration of the compound.

2. The method of claim 1, wherein the compound is selected from the group consisting of a fat, a protein, a glycoprotein, a lipoprotein, a carbohydrate, and a steroid.

3. The method of claim 2, wherein the steroid is free cholesterol.

4. The method of claim 2, wherein the steroid is esterfied cholesterol.

5. The method of claim 2, wherein the steroid is total cholesterol.

6. The method of claim 1, wherein in the step of placing (step (a)), the receptor presses against the skin thereby removing a portion of the blood within the skin.

7. The method of claim 1, wherein in the step of placing (step (a)), the receptor is clamped against the skin thereby removing a portion of the blood within the skin.

8. A method of identifying a clinical condition in need of treatment in a human or animal, the method comprising the steps of:

(i) determining the concentration of a compound in the skin as defined in claim 1;

and

(ii) correlating the concentration of the compound to the clinical condition in need of treatment, using a correlation algorithm.

9. The method of claim 8, wherein the compound is selected from the group consisting of a fat, a protein, a glycoprotein, a lipoprotein, a carbohydrate, and a steroid.

10. The method of claim 9, wherein the steroid is free cholesterol.

11. The method of claim 9, wherein the steroid is esterfied cholesterol.

12. The method of claim 9, wherein the steroid is total cholesterol.

13. A method for assessing the risk of a clinical condition in a human or animal, the method comprising the steps of:

(i) determining the concentration of a compound in the skin as defined in claim 1;

and

(ii) correlating the concentration of the compound to the risk of a clinical condition in need of treatment by using a correlation algorithm.

14. The method of claim 13, wherein the compound is selected from the group consisting of a fat, a protein, a glycoprotein, a lipoprotein, a carbohydrate, and a steroid.

15. The method of claim 14, wherein the steroid is free cholesterol.

16. The method of claim 14, wherein the steroid is esterfied cholesterol.

17. The method of claim 14, wherein the steroid is total cholesterol.

18. A method of assessing the risk of a clinical condition in an animal or human comprising the steps of:

(i) determining the concentration of a compound in the skin as defined in claim 1;

and

(ii) correlating the concentration of the compound to the risk of a clinical condition in need of treatment by using a correlation algorithm.

19. The method of claim 18, wherein the compound is selected from the group consisting of a fat, a protein, a glycoprotein, a lipoprotein, a carbohydrate, and a steroid.

20. The method of claim 19, wherein the steroid is free cholesterol.

21. The method of claim 19, wherein the steroid is esterfied cholesterol.

22. The method of claim 19, wherein the steroid is total cholesterol.

23. A method for assessing the risk for a disease of a human or animal comprising the steps of:

(a) placing a part of the skin against a receptor;

(b) directing electromagnetic radiation (EMR) from the near-infrared spectrum onto the skin;

(c) measuring a quantity of EMR reflected by, or transmitted through, the skin with a detector; and

(d) performing a quantitative mathematical analysis of the quantity of EMR to determine the scores of a clinical test.

24. An apparatus comprising:

a clamp having a first and a second end, the first end comprising one or more than one lever, and the second end comprising one or more than one receptor member to receive a sample of skin, wherein release of the one or more than one lever brings the one or more than one receptor member together over the sample of skin, the one or more than one receptor member house one or more than one input fiber optic elements for introducing an input electromagnetic radiation (EMR) to the skin sample, and one or more than one output optic fiber elements to remove an output EMR signal after interaction with one or more than one compounds within the skin.

25. The apparatus of claim 24, wherein the input and output optic fiber elements are adjacent each other within a fiber optic bundle within one receptor member.

26. The apparatus of claim 24, wherein the input and output optic fiber elements are located within separate receptor members.