Oximeter Probe with Light Wavelengths to Avoid Surgical Dyes

Patent metadata

Field	Value
Publication number	US-2016100781-A1
Application number	US-201514977578-A
Country	US
Kind code	A1
Filing date	Dec 21, 2015
Priority date	May 3, 2012
Publication date	Apr 14, 2016
Grant date	—

Abstract

A tissue oximetry device utilizes at least three or at least four different wavelengths of light for collection of reflectance data where the different wavelengths are longer than 730 nanometers. The three or four wavelengths are utilized to generate a range of reflectance data suited for accurate determination of oxygenated hemoglobin and deoxygenated hemoglobin concentrations. The relatively long wavelengths decrease optical interference from certain dyes, particularly methylene blue and PVPI, which may be present on tissue being analyzed for viability and further enhance the generation of accurate reflectance data. The wavelengths are 760 nanometers, 810 nanometers, and 850 nanometers, or 760 nanometers, 810 nanometers, 850 nanometers, and 900 nanometers.

First claim

The invention claimed is:

1 . A method comprising:
providing a sensor head for a tissue oximetry device comprising: a plurality of detector structures arranged asymmetrically in a circular arrangement, asymmetric about a point on a line intersecting a circle of the circular arrangement; a first source structure at the first point of the circle of the circular arrangement, wherein the first source structure is configured to emit at least a first wavelength of light longer than about 730 nanometers; a second source structure positioned at the second point of the circle of the circular arrangement, wherein the second source structure is configured to emit at least a second wavelength of light longer than about 730 nanometers; a first detector structure on the circle of the detector structures, wherein a first distance is from the first detector structure to the first source structure, a second distance is from the first detector structure to the second source structure, and the first distance is greater than the second distance; a second detector structure on the circle of the detector structures, wherein a third distance is from the second detector structure to the first source structure, a fourth distance is from the second detector structure to the second source structure, and the fourth distance is greater than the third distance; a third detector structure on the circle of the detector structures, wherein a fifth distance is from the third detector structure to the first source structure, a sixth distance is from the third detector structure to the second source structure, the fifth distance is different from the first distance and the second distance, and the sixth distance is different from the first distance and the second distance; and a fourth detector structure on the circle of the detector structures, wherein a seventh distance is from the fourth detector structure to the first source structure, an eighth distance is from the fourth detector structure to the second source structure, the seventh distance is different from the first, second, fifth, and sixth distances, and the eighth distance is different from the first, second, fifth, and sixth distances; and determining an oxygen saturation value for a tissue to be measured using the first wavelength of light from the first source structure and the second wavelength of light from the second source structure emitted into the tissue and corresponding reflected light received by at least two of the detectors.

2 . The method of claim 1 wherein the determining an oxygen saturation value for a tissue comprises:
receiving digital reflectance data for the reflected light received by the at least two of the detectors;
calculating absorption coefficients using the digital reflectance data;
solving a set of reflection coefficient equations for the tissue to be measured using the absorption coefficients to determining concentration values of at least oxygenated hemoglobin and deoxygenated hemoglobin; and
determining an oxygen saturation value for the tissue using the concentration values of oxygenated hemoglobin and deoxygenated hemoglobin.

3 . The method of claim 1 wherein the first wavelength of light is at least one of 760 nanometers, 810 nanometers, 850 nanometers, or 900 nanometers.

4 . The method of claim 1 wherein the first wavelength of light is at least one of 760 nanometers, 810 nanometers, or 850 nanometers, and the second wavelength of light is at least one of 760 nanometers, 810 nanometers, 850 nanometers, or 900 nanometers.

5 . The method of claim 1 wherein the tissue oximetry device is a handheld tissue oximetry device comprising the housing comprising the processor, memory, display, and battery, and the sensor head is coupled to the housing.

6 . The method of claim 1 wherein an enclosure of the tissue oximetry device comprises the sensor head, the sensor head is at an end of the tissue oximetry device, and when the sensor head is placed against the tissue to be measured, a display of the tissue oximetry device faces a user, and the display is coupled to the enclosure.

7 . The method of claim 1 wherein the first and second source structures are coupled via waveguides to light emitting diodes.

8 . The method of claim 1 wherein the first and second source structures are coupled via optical fibers to light emitting diodes.

9 . The method of claim 1 wherein the first and second source structures comprise light emitting diodes.

10 . The method of claim 1 wherein the first, second, third, and fourth detector structures are coupled via waveguides to photodetectors.

11 . The method of claim 1 wherein the first, second, third, and fourth detector structures are coupled via optical fibers to photodetectors.

12 . The method of claim 1 wherein the first, second, third, and fourth detector structures comprise photodetectors.

13 . The method of claim 1 wherein the first and second source structures are coupled via optical fibers to light emitting diodes, and the first, second, third, and fourth detector structures comprise photodetectors.

14 . The method of claim 1 wherein the first and second source structures are coupled via waveguides to light emitting diodes, and the first, second, third, and fourth detector structures comprise photodetectors.

15 . A method comprising:
providing a sensor head for a tissue oximetry device comprising: detectors arranged on the sensor head; and first and second light source structures positioned in a line on the sensor head, wherein the first source structure is configured to emit at least a first wavelength of light longer than about 730 nanometers, the second source structure is configured to emit at least a second wavelength of light longer than about 730 nanometers, a first detector of the detectors is a first distance from the first light source, a second detector of the detectors is a second distance from the second light source, a third detector of the set of detectors is a third distance from the first light source, no detector is positioned between the first detector and the third detector and the line passes between the first detector and the third detector and is closer to the first detector than the third detector, the first distance and the second distance are equal, the first distance and the third distance are not equal; and enclosing a processing module in a housing coupled to the sensor head, wherein the processing module is adapted determining an oxygen saturation value for a tissue to be measured using the first wavelength of light from the first source structure and the second wavelength of light from the second source structure emitted into the tissue and corresponding reflected light received by at least two of the detectors.

16 . The method of claim 15 wherein the determining an oxygen saturation value for a tissue comprises:
receiving digital reflectance data for the reflected light received by the at least two of the detectors;
calculating absorption coefficients using the digital reflectance data;
solving a set of reflection coefficient equations for the tissue to be measured using the absorption coefficients to determining concentration values of at least oxygenated hemoglobin and deoxygenated hemoglobin; and
determining an oxygen saturation value for the tissue using the concentration values of oxygenated hemoglobin and deoxygenated hemoglobin.

17 . The method of claim 15 wherein the first wavelength of light is at least one of 760 nanometers, 810 nanometers, 850 nanometers, or 900 nanom

Assignees

• Vioptix Inc

Inventors

• Bechtel Kate Leeann
• Lloyd Lester John

Classifications

• A61B2560/0431

  Portable apparatus, e.g. comprising a handle or case · CPC title

• A61B5/7405

  using sound · CPC title

• A61B5/742

  using visual displays (displays for heart-related electrical signals, e.g. ECG, A61B5/339) · CPC title

• A61B5/14552 Primary

  Details of sensors specially adapted therefor · CPC title

• A61B2562/0271

  Thermal or temperature sensors · CPC title