Melanin-Corrected Oxygen Saturation

1 . A system comprising:

an oximeter device comprising a sensor tip comprising source structures and detector structures at a distal end of the device, a processor, and a display associated with the oximeter device, wherein the processor of the oximeter device calculates a melanin-corrected oxygen saturation value, and displays the melanin-corrected oxygen saturation value on the display.

2 . The system of claim 1 wherein the processor of the oximeter device is configured to

use the sensor tip to make a first measurement and a second measurement to determine the melanin-corrected oxygen saturation value;

receive first information based on the first measurement of a first tissue at a first location when the sensor tip is positioned on the first tissue, wherein the melanin-corrected oxygen saturation value is unavailable for display after the first measurement is made and before the second measurement is made;

receive second information based on the second measurement of a second tissue at a second location when the sensor tip is positioned on the second tissue, wherein the second location is different from the first location; and

use the first information and second information to determine the melanin-corrected oxygen saturation value, wherein the melanin-corrected oxygen saturation value takes into account melanin components of the first tissue and second tissue, and the melanin components comprise eumelanin and pheomelanin.

3 . The system of claim 1 wherein the first location is at a first position of the body, the second location is at a second position of the body, and the first position and second position are contralateral with respect to each other.

4 . The system of claim 1 wherein the oximeter device is a handheld oximeter comprising a power source, and the processor is housed within an enclosure that also houses the source structures and detector structures of the sensor tip.

5 . The system of claim 1 wherein the oximeter device comprises a memory, and the memory stores first simulated reflectance curves for a first melanin content value, second simulated reflectance curves for a second melanin content value, and the first melanin content value is different from the second melanin content value.

6 . The system of claim 5 wherein the oximeter device is specially configured to:

based on the first and second information, determine a melanin content value for the first tissue and second tissue; and

use the determined melanin content value to select one of the first simulated reflectance curves or the second simulated reflectance curves stored in the memory by comparing the determined melanin content value against the melanin content value associated with each of the simulated reflectance curves.

7 . The system of claim 1 wherein the processor of the oximeter device is configured to:

transmit first light through a source structure into a first tissue at a first location to be measured, wherein the first tissue comprises a first melanin component, and the first melanin component comprises at least one of eumelanin or pheomelanin;

receive the first light at a detector structure that is reflected by the first tissue in response to the transmitted first light, wherein the received first light comprises a first melanin absorption component due to the first melanin component;

transmit second light through a source structure into a second tissue at a second location to be measured, wherein the second location is different from the first location, and second tissue comprises a second melanin component, and the second melanin component comprises at least one of eumelanin or pheomelanin;

receive the second light at a detector structure that is reflected by the second tissue in response to the transmitted light, wherein the received second light comprises a second melanin absorption component due to the second melanin component;

determine a melanin compensation component for a melanin absorption component due to a melanin component of tissue, wherein the melanin absorption component comprises the first and second melanin components; and

use the melanin compensation component, obtaining the melanin-corrected oxygen saturation value for the first tissue, wherein the melanin-corrected oxygen saturation value accounts for the melanin absorption component.

8 . The system of claim 1 wherein the processor of the oximeter device is configured to:

transmit first light through a source structure into a first tissue at a first location to be measured, wherein the first tissue comprises a first melanin component, and the first melanin component comprises at least one of eumelanin or pheomelanin;

receive the first light at a detector structure that is reflected by the first tissue in response to the transmitted first light, wherein the received first light comprises a first melanin absorption component due to the first melanin component;

determine a melanin compensation component for a melanin absorption component due to a melanin component of tissue, wherein the melanin absorption component comprises the first and second melanin components, wherein the determining the melanin compensation component for the melanin absorption component due to the melanin component comprises:

transmit second light through a source structure into a second tissue at a second location to be measured, wherein the second location is different from the first location, and the second tissue comprises a second melanin component, and the second melanin component comprises at least one of eumelanin or pheomelanin;

receive the second light at the detector structure that is reflected by the first tissue in response to the transmitted light, wherein the received second light comprises a second melanin absorption component due to the second melanin component;

determine a first plurality of absorption coefficients that are dependent on a plurality of wavelengths of the first light emitted into the first tissue when the measurement on the first tissue is performed; and

determine a second plurality of absorption coefficients that are dependent on the first plurality of wavelengths of the second light emitted into the second tissue when the measurement on the second tissue is performed; and

use the melanin compensation component, obtaining a melanin-corrected oxygen saturation value for the first tissue, wherein the melanin-corrected oxygen saturation value accounts for the melanin absorption component.

9 . The system of claim 8 wherein to determine the melanin compensation component for the melanin absorption component due to the melanin component comprises:

calculate a first angular deviation and a second angular deviation of a curve for the first plurality of absorption coefficients for the first tissue;

calculate a third angular deviation and a fourth angular deviation of a curve for the second plurality of absorption coefficients for the second tissue;

calculate a first angular difference between the first and second angular deviations and a second angular difference between the third and fourth angular deviations; and

calculate a relative change in oxygen saturation between the first and second tissues based on the first and second angular differences.

10 . The system of claim 8 comprising:

adjust the absorption coefficients of the second plurality of absorption coefficients for each wavelength of the first light using the reflectance data for the first tissue, wherein the melanin compensation component comprises the adjusted absorption coefficients; and

determine an oxygen saturation value for the second tissue using the adjusted absorption coefficients.

11 . The system of claim 9 comprising displaying on the display associated with the oximeter device, the melanin-corrected oxygen saturation value, wherein the melanin-corrected oxygen saturation value is a value for the relative change in oxygen saturation between the first and second tissues.

12 . The system of claim 11 wherein to determine the melanin compensation component for the melanin absorption component due to the melanin component comprises scaling the first and second angular differences with a scaling vector, and the scaling vector representing a 100 percent difference in oxygenation of a tissue phantom.

13 . The system of claim 8 wherein to determine the melanin compensation component for the melanin absorption component due to the melanin component comprises:

generate a third absorption coefficient by adjusting at least one of the coefficients of the first plurality of absorption coefficients using at least one of the absorption coefficients of the second plurality of absorption coefficients; and

generate the melanin-corrected oxygen saturation value for the first tissue using the third absorption coefficient.

14 . The system of claim 13 wherein to determine the melanin compensation component for the melanin absorption component due to the melanin component comprises:

fit first reflectance data for the first light received at a detector structure for the first tissue to a plurality of simulated reflectance curves for determining the at least one of the absorption coefficients of the first plurality of absorption coefficients, wherein the simulated reflectance curves include modeling for melanin in simulated tissue; and

determine the at least one of the absorption coefficients of the first plurality of absorption coefficients from one or more best fitting one of the simulated reflectance curves.

15 . The system of claim 14 wherein to determine the melanin compensation component for the melanin absorption component due to the melanin component comprises:

fit second reflectance data for the second light received at a detector structure for the second tissue to the plurality of simulated reflectance curves for determining the at least one of the absorption coefficients of the second plurality of absorption coefficients; and

determine the at least one of the absorption coefficients of the second plurality of absorption coefficients from one or more best fitting one of the simulated reflectance curves.

16 . The system of claim 7 comprising:

determine a first plurality of absorption coefficients that are dependent on a plurality of wavelengths of the first light emitted from into the first tissue when the measurement on the first tissue is performed;

determine a second plurality of absorption coefficients that are dependent on the plurality of wavelengths of the second light emitted into the second tissue when the measurement on the second tissue is performed;

generate a third absorption coefficient by adjusting at least one of the absorption coefficients of the first plurality of absorption coefficients using at least one of the absorption coefficients of the second plurality of absorption coefficients; and

generate the melanin-corrected oxygen saturation value for the first tissue using the third absorption coefficient.

17 . The system of claim 16 comprising:

fit first reflectance data, for the first light received at a detector structure for the first tissue, to a plurality of simulated reflectance curves for determining the at least one of the absorption coefficients of the first plurality of absorption coefficients, wherein the simulated reflectance curves include modeling for melanin in simulated tissue; and

determine the at least one of the absorption coefficients of the first plurality of absorption coefficients from one or more best fitting ones of the simulated reflectance curves.

18 . The system of claim 17 comprising:

fit second reflectance data, for the second light received at a detector structure for the second tissue, to the plurality of simulated reflectance curves for determining the at least one of the absorption coefficients of the second plurality of absorption coefficient; and

determine the at least one of the absorption coefficients of the second plurality of absorption coefficients from one or more best fitting one of the simulated reflectance curves.

19 . The system of claim 1 wherein a user provides to the oximeter an indication of a skin color of the tissue.

20 . The system of claim 2 wherein a user provides to the oximeter an indication of a skin color of the tissue.