Biological photometer

• US 7,186,217 B2
• Filed: 03/03/2003
• Issued: 03/06/2007
• Est. Priority Date: 03/26/2002
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi Medical Corporation (Hitachi, Ltd.)
• Inventors: Kawasaki, Shingo
• Primary Examiner(s): Winakur; Eric
• Assistant Examiner(s): BERHANU, ETSUB D
• Application Number:
  US10/509,104
• Publication Number:
  US 20050177033A1
• Time in Patent Office: 1,464 Days
• Field of Search: 600/322, 600/323, 600/324, 600/473, 600/476, 128/920, 128/923
• US Class Current: 600/300
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters

Abstract

A biological photometer having, in its signal processing unit, a memory unit in which characteristics of hemoglobin change pattern of healthy case and various diseases are stored as reference template, characteristic extraction unit in which characteristic of hemoglobin change patterns are extracted from hemoglobin signals measured in a photometer unit, and a judgment unit in which the characteristics of the hemoglobin change patterns thus extracted are compared with the reference templates stored in the memory unit so as to judge whether the subject is healthy or ill. As the characteristics of the hemoglobin change pattern, use is made of hemoglobin change pattern curve as well as factors determined therefrom such as latent time, maximum level, time for attaining the maximum level, differential quantitative change, integral quantitative change, etc. Using this biological photometer, various diseases can be easily and quantitatively diagnosed.

Claims

1. A biological photometer comprising a light source which generates light being irradiated to a subject, a photometer unit which detects light transmitted inside the subject and produces a hemoglobin signal corresponding to hemoglobin density inside the subject, and a signal processing unit which prepares hemoglobin variation information of the subject based on the hemoglobin signal and displays the hemoglobin variation information, characterized in that the signal processing unit is provided with a memory unit which stores characteristics of hemoglobin variation patterns of respective normal health and a variety of diseases as reference templates, a characteristic extraction unit which extracts characteristics of a hemoglobin variation pattern of the subject based on the hemoglobin signal produced by the photometer unit, and a judgment unit which judges normal health or a kind of disease of the subject through comparison between the extracted characteristics of the hemoglobin variation pattern and respective reference templates of the normal health and the variety of diseases stored in the memory unit.

2. A biological photometer according to claim 1, characterized in that the characteristics of hemoglobin variation pattern includes at least one of a hemoglobin variation pattern curve, latent time, maximum level, time for attaining the maximum level, differential quantitative change and integral quantitative change determined from the curve.

3. A biological photometer according to claim 2, wherein the latent time is a period from beginning of a task to a moment when the hemoglobin signal exceeds a threshold value.

4. A biological photometer according to claim 2, wherein the time for attaining the maximum level is a period from a moment when the hemoglobin signal exceeds a threshold value to a moment when the hemoglobin signal attains the maximum level.

5. A biological photometer according to claim 2, wherein the integral quantitative change is an area determined by integrating the hemoglobin signal variation curve from a moment when the hemoglobin signal exceeds a threshold value to a moment when the hemoglobin signal drops below the threshold value.

6. A biological photometer according to claim 2, wherein the judgment unit determines whether the characteristics of the measured hemoglobin variation is within a standard deviation in the reference template of a predetermined disease and if within the standard deviation, is judged as the disease.

7. A biological according to claim 2, wherein, when a predetermined number of characteristics of hemoglobin variation among a plurality of characteristics of hemoglobin variation indicates a disease, the judgment unit judges the indicated disease as the disease.

8. A biological photometer according to claim 1, wherein the reference templates stored in the memory unit are prepared by statistically processing hemoglobin variation signals measured in advance of normal health persons and patients of the variety of diseases.

9. A biological photometer according to claim 1, wherein the reference templates stored in the memory unit are prepared by subjecting hemoglobin signals of a plurality of normal health persons and a plurality of patients of the variety of diseases to adding and averaging processing.

10. A biological photometer according to claim 9, wherein the characteristics of hemoglobin variation of the reference templates are determined from variation patterns of the hemoglobin signals after being subjected to the adding and averaging processing.

11. A biological photometer according to claim 9, wherein in a case of a disease when the hemoglobin variation is limited at a specific region, the characteristics of hemoglobin variation of the reference templates are determined by adding and averaging hemoglobin signals only from measurement points covered by the specific region.

12. A biological photometer according to claim 1, wherein the judgment unit judges a kind of disease based on a correlation between the measured hemoglobin signals and an average of the variation patterns of the reference templates stored in the memory unit.

13. A biological photometer according to claim 1, wherein the judgment unit determines correlations between the measured hemoglobin signals and an average of the variation patterns of the plurality of reference templates stored in the memory unit and judges a kind of disease based on a reference template having the highest correlation or a reference template having a predetermined value.

14. A biological photometer according to claim 1, wherein the signal processing unit displays a judgment result from the judgment unit.

15. A biological photometer comprising;

a light source unit which generates light having a predetermined wavelength in a region from visual to infrared;

an optical fiber which guides the light from the light source unit to a detection portion of a subject and irradiates the guided light thereto;

a photometer unit which detects light irradiated from the optical fiber and transmitted inside the subject and produces a hemoglobin signal corresponding to hemoglobin density at the detection portion of the subject; and

a signal processing unit which prepares a hemoglobin variation at the detection portion of the subject along a time axis based on the hemoglobin signal from the photometer unit and displays the hemoglobin variation, characterized in that,

the signal processing unit is provided with a characteristic extraction unit which extracts characteristics of a hemoglobin variation pattern based on the prepared hemoglobin variation at the detection portion of the subject, a memory unit which stores characteristics of hemoglobin variation patterns at the same detection portions of respective normal health and a variety of diseases in a form of reference templates, and a judgment unit which compares the characteristics of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and the reference templates representing the characteristics of the hemoglobin variation patterns at the same detection portions of the respective normal health and variety of diseases stored in the memory unit and judges whether the subject is in normal health or in any one of the diseases.

16. A biological photometer according to claim 15, characterized in that the judgment unit judges whether the subject is in normal health or in any one of the diseases based on a comparison between at least one of latent time, maximum level, time for attaining the maximum, differential change value and integral change value of a hemoglobin variation pattern curve of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and the characteristics corresponding to the reference templates of normal health and the variety of diseases at the same detection portions stored in the memory unit.

17. A biological photometer according to claim 16, wherein the latent time is a period from beginning of a task to a moment when the hemoglobin signal exceeds a threshold value.

18. A biological photometer according to claim 16, wherein the time for attaining the maximum level is a period from a moment when the hemoglobin signal exceeds a threshold value to a moment when the hemoglobin signal attains the maximum level.

19. A biological photometer according to claim 16, wherein the integral quantitative change is an area determined by integrating the hemoglobin signal variation curve from a moment when the hemoglobin signal exceeds a threshold value to a moment when the hemoglobin signal drops below the threshold value.

20. A biological photometer according to claim 16, wherein the judgment unit determines whether the characteristics of the measured hemoglobin variation is within a standard deviation in the reference template of a predetermined disease and if within the standard deviation, is judged as the disease.

21. A biological photometer according to claim 16, wherein, when a predetermined number of characteristics of hemoglobin variation among a plurality of characteristics of hemoglobin variation indicates a disease, the judgment unit judges the indicated disease as the disease.

22. A biological photometer according to claim 15, wherein the reference templates stored in the memory unit are prepared by statistically processing hemoglobin variation signals measured in advance of normal health persons and patients of the variety of diseases.

23. A biological photometer according to claim 15, wherein the reference templates stored in the memory unit are prepared by subjecting hemoglobin signals of a plurality of normal health persons and a plurality of patients of the variety of diseases to adding and averaging processing.

24. A biological photometer according to claim 23, wherein the characteristics of hemoglobin variation of the reference templates are determined from variation patterns of the hemoglobin signals after being subjected to the adding and averaging processing.

25. A biological photometer according to claim 23, wherein in a case of a disease when the hemoglobin variation is limited at a specific region, the characteristics of hemoglobin variation of the reference templates are determined by adding and averaging hemoglobin signals only from measurement points covered by the specific region.

26. A biological photometer according to claim 15, wherein the judgment unit judges a kind of disease based on a correlation between the measured hemoglobin signals and an average of the variation patterns of the reference templates stored in the memory unit.

27. A biological photometer according to claim 15, wherein the judgment unit determines correlations between the measured hemoglobin signals and an average of the variation patterns of the plurality of reference templates stored in the memory unit and judges a kind of disease based on a reference template having the highest correlation or a reference template having a predetermined value.

28. A biological photometer according to claim 15, wherein the signal processing unit displays a judgment result from the judgment unit.

29. A biological photometer comprising;

a light source unit which generates light having a predetermined wavelength in a region from visual to infrared;

an optical fiber which guides the light from the light source unit to a detection portion of a subject and irradiates the guided light thereto;

a photometer unit which detects light irradiated from the optical fiber and transmitted inside the subject and produces a hemoglobin signal corresponding to hemoglobin density at the detection portion of the subject; and

a signal processing unit which prepares a hemoglobin variation at the detection portion of the subject along a time axis based on the hemoglobin signal from the photometer unit and displays the hemoglobin variation, characterized in that,

the signal processing unit is provided with a characteristic extraction unit which extracts characteristics of a hemoglobin variation pattern based on the prepared hemoglobin variation at the detection portion of the subject, a memory unit which stores characteristics of hemoglobin variation patterns at the same detection portions of respective normal health and a variety of diseases in a form of reference templates, and a judgment unit which compares the characteristics of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and the reference templates representing the characteristics of the hemoglobin variation patterns at the same detection portions of the respective normal health and variety of diseases stored in the memory unit and judges whether the subject is in normal health or in any one of the diseases;

characterized in that the judgment unit determines a correlation coefficient ρ

between a hemoglobin variation pattern curve of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and a hemoglobin variation pattern curve in the reference templates of normal health and the variety of diseases at the same detection portions stored in the memory unit and judges whether the subject is in normal health or in any one of the diseases based on the determined correlation coefficient.

30. A biological photometer according to claim 29, wherein the signal processing unit displays correlations with respective diseases.

31. A biological photometer comprising a light source which generates light being irradiated to a subject, a photometer unit which detects light transmitted inside the subject and produces a hemoglobin signal corresponding to hemoglobin density inside the subject and a signal processing unit which prepares hemoglobin variation information of the subject based on the hemoglobin signal and displays the hemoglobin variation information, characterized in that the signal processing unit is provided with a memory unit which stores characteristics of hemoglobin variation patterns of respective normal health and a variety of diseases as reference templates, a characteristic extraction unit which extracts characteristics of a hemoglobin variation pattern of the subject based on the hemoglobin signal produced by the photometer unit, and a judgment unit which idles normal health or a kind of disease of the subject through comparison between the extracted characteristics of the hemoglobin variation pattern and the respective reference templates of the normal health and the variety of diseases stored in the memory unit;

characterized in that the signal processing unit modifies the reference templates at the same detection portions of the normal health and the variety of diseases stored in the memory unit by making use of the characteristics of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and a judgment result by the judgment unit whether the subject is in normal health or any one of the diseases based on the characteristics.

32. A biological photometer comprising;

a light source unit which generates light having a predetermined wavelength in a region from visual to infrared;

an optical fiber which guides the light from the light source unit to a detection portion of a subject and irradiates the guided light thereto;

a photometer unit which detects light irradiated from the optical fiber and transmitted inside the subject and produces a hemoglobin signal corresponding to hemoglobin density at the detection portion of the subject; and

a signal processing unit which prepares a hemoglobin variation at the detection portion of the subject along a time axis based on the hemoglobin signal from the photometer unit and displays the hemoglobin variation, characterized in that,

the signal processing unit is provided with a characteristic extraction unit which extracts characteristics of a hemoglobin variation pattern based on the prepared hemoglobin variation at the detection portion of the subject, a memory unit which stores characteristics of hemoglobin variation patterns at the same detection portions of respective normal health and a variety of diseases in a form of reference templates, and a judgment unit which compares the characteristics of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and the reference templates representing the characteristics of the hemoglobin variation patterns at the same detection portions of the respective normal health and a variety of diseases stored in the memory unit and judges whether the subject is in normal health or in any one of the diseases;

characterized in that the signal processing unit modifies the reference templates at the same detection portions of the normal health and the variety of diseases stored in the memory unit by making use of the characteristics of the hemoglobin variation pattern at the detection portion of the subject extracted by the characteristic extraction unit and a judgment result by the judgment unit whether the subject is in normal health or any one of the diseases based on the characteristics.