Method of removing abnormal data and blood component spectroscopy analysis system employing the same

• US 20040204865A1
• Filed: 01/07/2004
• Published: 10/14/2004
• Est. Priority Date: 01/07/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Yoon, Gil-won, Lee, Jong-youn
• Granted Patent: US 8,507,281 B2
• Time in Patent Office: Days
• US Class Current: 702/25
• 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: Y10T 436/102499 Blood gas standard or control
• CPC Class Codes: Y10T 436/105831 Protein or peptide standard or control [e.g., hemoglobin, etc.]
• CPC Class Codes: Y10T 436/106664 Blood serum or blood plasma standard or control

Abstract

A method of removing abnormal data in a blood component analysis system using spectroscopy to estimate a concentration of a blood component by analyzing a photo-plethysmographic (PPG) signal obtained by radiating light of first and second wavelengths reacting to the blood component on a subject and detecting light corresponding to the first and second wavelengths output from the subject, includes collecting the PPG signal corresponding to the first and second wavelengths for a predetermined unit period of time, calculating “n” parameters, with respect to “n” pulse data included in the collected PPG signal, where n is a positive integer, calculating an average of the “n” parameters, and comparing a ratio of a number of parameters whose deviation from the average is greater than a predetermined standard deviation to the “n” parameters with a predetermined removal reference value to determine whether the “n” pulse data is valid.

Claims

1. A method of removing abnormal data in a blood component analysis system using spectroscopy to estimate a concentration of a blood component by analyzing a photo-plethysmographic (PPG) signal obtained by radiating light of first and second wavelengths reacting to the blood component on a subject and detecting light corresponding to the first and second wavelengths output from the subject, the method comprising:

(a) collecting the PPG signal corresponding to the first and second wavelengths for a predetermined unit period of time;

(b) calculating “

n”

parameters, with respect to “

n”

pulse data included in the collected PPG signal, where n is a positive integer;

(c) calculating an average of the “

n”

parameters; and

(d) comparing a ratio of a number of parameters whose deviation from the average is greater than a predetermined standard deviation to the “

n”

parameters with a predetermined removal reference value to determine whether the “

n”

pulse data is valid.

2. The method as claimed in claim 1, further comprising:

updating all of the “

n”

pulse data and repeating steps (b) through (d) when the ratio is equal to or greater than the predetermined removal reference value in step (d).

3. The method as claimed in claim 1, further comprising:

updating at least one of the “

n”

pulse data and repeating steps (b) through (d) when the ratio is equal to or greater than the predetermined removal reference value in step (d).

4. The method as claimed in claim 1, wherein the standard deviation is determined according to the first and second wavelengths.

7. The method as claimed in claim 1, wherein the “

n”

pulse data are generated from a modulated signal influenced by a change in a blood flow caused by an external pressure.

8. The method as claimed in claim 1, further comprising:

storing the “

n”

pulse data when the ratio is less than the predetermined removal reference value in step (d).

5. The method as claimed in 4, wherein when the first and second wavelengths correspond to an isobestic point, the standard deviation is set to ±

3.5% through ±

4.5%.

6. The method as claimed in 4, wherein when the first and second wavelengths are in one of a red range and an infrared range, the standard deviation is set to ±

1.5% through ±

2.5%.

9. A computer-readable recording medium in a blood component analysis system using spectroscopy to estimate a concentration of a blood component by analyzing a photo-plethysmographic (PPG) signal obtained by radiating light of first and second wavelengths reacting to the blood component on a subject and detecting light corresponding to the first and second wavelengths output from the subject, the computer-readable recording medium comprising:

a first program for calculating “

n”

parameters with respect to “

n”

pulses included in a PPG signal corresponding to the first and second wavelengths, the PPG signal being collected for a predetermined unit period of time, where n is a positive integer; and

a second program for calculating an average of the “

n”

parameters and comparing a ratio of a number of parameters whose deviation from the average is greater than a predetermined standard deviation to the “

n”

parameters with a predetermined removal reference value to determine whether the “

n”

pulse data is valid.

10. The computer readable recording medium as claimed in claim 9, further comprising:

a third program for storing “

n”

pulse data when the second program determines the “

n”

pulse data is valid, and updating at least one of the “

n”

pulse data when the second program determines the “

n”

pulse data is not valid and iterating the first and second programs for updated data.

11. The computer readable recording medium as claimed in claim 10, wherein all of the “

n”

pulse data is updated.

12. A blood component analysis system using spectroscopy, comprising:

a light emitter having at least a first light source emitting light of a first wavelength and a second light source emitting light of a second wavelength, each first and second wavelengths reacting to a particular blood component, the first and second light source providing light to a subject;

a light receiver detecting light output from the subject and outputting an electrical signal in response thereto; and

a signal processor extracting a photo-plethysmographic (PPG) signal corresponding to the first and second wavelengths reacting to the particular blood component from the electrical signal, calculating an average of of “

n”

parameters with respect to “

n”

pulses included in the PPG signal corresponding to the first and second wavelengths, and comparing a ratio of the number of parameters whose deviation from the average is greater than a predetermined standard deviation to the “

n”

parameters with a predetermined removal reference value to determine whether the “

n”

pulse data is valid, where n is a positive integer.

13. The blood component analysis system as claimed in claim 12, wherein the signal processor includes a First In First Out (FIFO) data buffer storing the “

n”

pulse data, and when the “

n”

pulse data is determined as being invalid, divides the “

n”

pulse data into predetermined unit groups, replaces a first predetermined unit group composed of first input data with the same amount of new data as the first predetermined unit group, and determines whether new “

n”

pulse data is valid.

14. The blood component analysis system as claimed in claim 12, wherein the standard deviation is determined according to the first and second wavelengths.

15. The blood component analysis system as claimed in claim 14, wherein when the first and second wavelengths correspond to an isobestic point, the standard deviation is set to ±

3.5% through ±

4.5%.

16. The blood component analysis system as claimed in claim 14, wherein when the first and second wavelengths are in a red range or an infrared range, the standard deviation is set to ±

1.5% through ±

2.5%.

17. The blood component analysis system as claimed in claim 12, wherein the “

n”

pulse data are generated from a modulated signal influenced by a change in blood flow caused by an external pressure.

18. The blood component analysis system as claimed in claim 12, further comprising:

a storage unit storing the “

n”

pulse data determined to be valid.

19. The blood component analysis system as claimed in claim 12, wherein the signal processor controls a timing of the light emitter.