METHOD FOR MEASURING THE AREA OF A SAMPLE DISPOSED WITHIN AN ANALYSIS CHAMBER

• US 20090257632A1
• Filed: 04/09/2009
• Published: 10/15/2009
• Est. Priority Date: 04/09/2008
• Status: Active Grant

• Current Assignee: Abbott Point Of Care Incorporated (Abbott Laboratories)
• Original Assignee: Abbott Point Of Care Incorporated (Abbott Laboratories)
• Inventors: Wardlaw, Stephen C., Lalpuria, Niten V.
• Granted Patent: US 8,326,008 B2
• Time in Patent Office: Days
• US Class Current: 382/128
• CPC Class Codes: G01N 15/05 in blood
• CPC Class Codes: G01N 2015/055 for hematocrite determination
• CPC Class Codes: G01N 21/17 Systems in which incident light is modified in accordance with the properties of the material investigated where the material investigated is optically excited causing a change in wavelength of the incident light G01N21/63
• CPC Class Codes: G06T 2207/10056 Microscopic image
• CPC Class Codes: G06T 2207/10064 Fluorescence image
• CPC Class Codes: G06T 2207/30024 Cell structures in vitro; Tissue sections in vitro
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/62 of area, perimeter, diameter or volume
• CPC Class Codes: Y10T 436/11 Automated chemical analysis

Abstract

A method for determining the area of an analysis chamber covered by a biologic fluid sample quiescently residing within the chamber is provided. The chamber has a first panel with an interior surface, and a second panel with an interior surface, both of which panels are transparent. The method includes the steps of: a) illuminating the sample residing within the analysis chamber at one or more wavelengths operable to highlight interfaces between the sample and air, and to highlight a constituent within the sample; b) imaging the sample along the one or more wavelengths, and producing image signals representative of the interaction of the one or more wavelengths with the sample; c) determining a location of at least one interface between the sample and air, using the image signals; d) determining a location of one or more constituents within the sample relative to the at least one sample-air interface using the image signals; and e) determining an area of the chamber containing the sample, using the location of the one or more constituents and the at least one sample-air interface.

Claims

1. A method for determining the area of an analysis chamber covered by a biologic fluid sample quiescently residing within the chamber, which chamber has a first panel with an interior surface, and a second panel with an interior surface, both of which panels are transparent, the method comprising the steps of:

illuminating the sample residing within the analysis chamber at one or more wavelengths operable to highlight interfaces between the sample and air, and to highlight at least one constituent within the sample;

imaging the sample along the one or more wavelengths, and producing image signals representative of the interaction of the one or more wavelengths with the sample;

determining a location of at least one interface between the sample and air, using the image signals;

determining a location of one or more constituents within the sample relative to the at least one sample-air interface using the image signals; and

determining an area of the chamber containing the sample, using the location of the one or more constituents and the at least one sample-air interface.

2. The method of claim 1, further comprising the step of masking either a sample region containing the one or more constituents on a first side of the sample-air interface, or a no-sample region on a second side of the sample-air interface, which second side is opposite the first side.

3. The method of claim 2, wherein the masking includes a digital binary masking of image units within the sample region or the no-sample region.

4. The method of claim 3, wherein the area of the chamber containing the sample is determined by summing an area per image unit in at least one of the masked or unmasked regions.

5. The method of claim 3, wherein the area of the chamber containing the sample is determined by summing the area of the image units in the no-sample region and subtracting them from a known chamber area.

6. The method of claim 2, wherein the step of masking includes iteratively masking image units extending outwardly from image units aligned with a constituent, until one or more of masked imaged units, sample-air interface, and a chamber lateral barrier are encountered.

7. The method of claim 2, wherein the step of masking includes iteratively masking image units extending outwardly from image units aligned with the at least one sample-air interface, until other masked imaged units or a chamber lateral barrier are encountered.

8. The method of claim 1, wherein the step of determining an area of the chamber containing the sample, using the location of the one or more constituents and the at least one sample/air interface, includes defining one or more sample regions, each containing one or more constituents, and one or more no-sample regions, each containing no constituents, wherein one of the at least one sample-air interfaces is disposed between each sample region and no-sample region.

9. The method of claim 8, further comprising the step of masking either the one or more sample regions or the one or more no-sample regions.

10. The method of claim 8, wherein the area of the chamber containing the sample is determined by summing the area of the image units in each of the one or more sample regions.

11. The method of claim 8, wherein the area of the chamber containing the sample is determined by summing the area of the image units in each of the one or more no-sample regions and subtracting them from a known chamber area.

12. The method of claim 8, wherein the masking includes a digital binary masking of image units within the one or more sample regions or no-sample regions.

13. The method of claim 1, wherein the constituents are red blood cells.

14. The method of claim 13, wherein the step of illuminating the sample residing within the analysis chamber includes illuminating the sample at a first wavelength and a second wavelength, which second wavelength is different from the first wavelength.

15. The method of claim 14, wherein illuminating the sample using the first wavelengths causes the interfaces between the sample and air to be highlighted in the image.

16. The method of claim 15, wherein the second wavelength is a wavelength absorbed by hemoglobin.

17. The method of claim 1, wherein the constituents are one or both of white blood cells and platelets, which have been colored by a sensible colorant.

18. The method of claim 1, wherein the chamber includes lateral barriers, which barriers include a sensible colorant.

19. The method of claim 1, further comprising the step of determining a volume of the sample disposed within the chamber using the determined area of the chamber containing the sample, and a known chamber height.

20. A method for determining the area of an analysis chamber covered by a biologic fluid sample disposed within the chamber, comprising the steps of:

depositing a biologic fluid sample into an analysis chamber adapted to quiescently hold the sample for analysis, the chamber defined by an interior surface of a first panel, and an interior surface of a second panel, wherein both panels are transparent;

illuminating the sample disposed within the analysis chamber at one or more wavelengths operable to highlight interfaces between the sample and air, and at one or more wavelengths operable to interact with a constituent within the sample;

imaging the sample along the one or more first wavelengths and one or more second wavelengths, and producing image signals representative of the interaction of the first and second wavelengths with the sample;

determining at least one interface between the sample and air, using the image signals;

determining a location of one or more constituents within the sample relative to the at least one sample-air interface using the image signals;

masking either a sample region containing the one or more constituents on a first side of the sample-air interface, or a no-sample region on a second side of the sample-air interface, which second side is opposite the first side;

determining an area of the chamber containing the sample, using at least one of the masked sample region and the no-sample region.

21. The method of claim 20, wherein the chamber includes a portion bounded by one or more barriers that form a known area disposed therebetween.

22. A method for determining the volume of a biologic fluid sample quiescently residing within an analysis chamber, which chamber has a transparent first panel with an interior surface, a transparent second panel with an interior surface, and a known or determinable height, the method comprising the steps of:

illuminating the sample residing within the analysis chamber at one or more wavelengths operable to highlight interfaces between the sample and air, and to highlight at least one constituent within the sample;

imaging the sample along the one or more wavelengths, and producing image signals representative of the interaction of the one or more wavelengths with the sample;

determining a location of at least one interface between the sample and air, using the image signals;

determining a location of one or more constituents within the sample relative to the at least one sample-air interface using the image signals;

determining an area of the chamber containing the sample, using the location of the one or more constituents and the at least one sample-air interface; and

determining the volume of the sample disposed within the chamber using the determined area of the chamber containing the sample and the known height or determinable of the chamber.

23. The method of claim 22, wherein the constituents are red blood cells.

24. The method of claim 23, wherein the step of illuminating the sample residing within the analysis chamber includes illuminating the sample at a first wavelength and a second wavelength, which second wavelength is different from the first wavelength.

25. The method of claim 24, wherein illuminating the sample using the first wavelengths causes the interfaces between the sample and air to be highlighted in the image.

26. The method of claim 25, wherein the second wavelength is a wavelength absorbed by hemoglobin.

27. The method of claim 22, wherein the constituents are one or both of white blood cells and platelets, which have been colored by a sensible colorant.