| 主权项 |
1. A handheld tissue oximetry device comprising:
a housing comprising: a processor contained within the housing; a memory, contained within the housing, wherein the memory is coupled to the processor; a display, coupled to the processor, wherein the display is visible from an exterior of the housing; a battery, contained within the housing, coupled to and supplies power to the processor, memory, and display; and a tip portion of the housing; a sensor module, coupled to the processor, wherein the sensor module comprises a probe face that is retained by the tip portion of the housing at a relatively fixed position with respect to the housing and that is placed against and faces tissue to be measured, and the sensor module comprises:
a first plurality of detector structures, formed on the probe face, arranged in a circular arrangement, symmetrically about a point on a line intersecting a circle of the circular arrangement at a first point and a second point;a second plurality of detector structures, formed on the probe face, arranged asymmetrically about the point on the line in the circular arrangement;a first source structure, formed on the probe face, positioned at the first point of the circle of the circular arrangement;a second source structure, formed on the probe face, positioned at the second point of the circle of the circular arrangement;a first source diode and a second source diode adapted to emit radiation having at least four wavelengths longer than 730 nanometers;a first optical fiber optically coupled between the first source diode and the first source structure;a second optical fiber optically coupled between the second source diode and the second source structure, wherein the first optical fiber transmits radiation emitted by the first source diode to the first source structure, and the second optical fiber transmits radiation emitted by the second source diode to the second source structure;a first detector structure on the circle of the first plurality of 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 first plurality of detector structures, arranged symmetrically with respect to the first detector structure about the point on the line, 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;the first distance is the same as the fourth distance, and the second distance is the same as the third distance;a third detector structure on the circle of the second plurality of detector structures, arranged asymmetrically with respect to the first plurality of detectors structures about the point on the line, 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; anda fourth detector structure on the circle of the second plurality of detector structures, arranged asymmetrically with respect to the first plurality of detectors structures and the third detector structure about the point on the line, 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, wherein the first distance is greater the fifth, sixth, seventh, and eighth distances, and the second distance is less than the fifth, sixth, seventh, and eight distances, and wherein the processor is adapted to: control the first and second diodes to emit the radiation at the four wavelengths to the first and second source structures via the first and second optical fibers and to emit the radiation at the four wavelengths into tissue to be measured from the first and second source structures, control the first and second plurality of detector structures to detect the radiation at the four wavelengths subsequent to reflection of the radiation from the tissue to be measured, receive digital reflectance data for the detected radiation detected by the first and second plurality of detector structures, calculate a plurality of absorption coefficients using the digital reflectance data for the radiation at the four wavelengths, solve a set of reflection coefficient equations for the tissue to be measured using the plurality of absorption coefficients to determine concentration values of oxygenated hemoglobin, deoxygenated hemoglobin, water, and melanin for the tissue, wherein the concentration values of oxygenated hemoglobin and deoxygenated hemoglobin are relatively independent of the concentration values of water and melanin for the tissue, and determine the absolute oxygen saturation for the tissue using the concentration values of oxygenated hemoglobin and deoxygenated hemoglobin. |
