Medical sensor for reducing motion artifacts and technique for using the same
View Patent ↗A sensor for pulse oximetry or other applications utilizing spectrophotometry may be adapted to reduce motion artifacts by fixing the optical distance between an emitter and detector. A flexible sensor is provided with a stiffening member to hold the emitter and detector of the sensor in a relatively fixed position when applied to a patient. Further, an annular or partially annular sensor is adapted to hold an emitter and detector of the sensor in a relatively fixed position when applied to a patient. A clip-style sensor is provided with a spacer that controls the distance between the emitter and detector.
1. A sensor comprising:
a substantially annular or partially annular rigid sensor body configured to retain the sensor on a patient's digit, wherein the sensor body forms a tissue-contacting surface of the sensor; and
an emitter and a detector disposed on the tissue-contacting surface of the sensor body, wherein the sensor body is adapted to hold the emitter and detector at a fixed optical distance relative to one another and relative to the patient's digit when the sensor is attached to a patient and when the sensor experiences an external tapping force or when the digit applies a flexing force to the sensor.
2. The sensor, as set forth in claim 1 , wherein the sensor body is adapted to have an adjustable diameter.
3. The sensor, as set forth in claim 1 , wherein the sensor body comprises an adjustment strap.
4. The sensor, as set forth in claim 3 , wherein the adjustment strap comprises a plurality of notches adapted to fix the diameter of the sensor body.
5. The sensor, as set forth in claim 1 , wherein the sensor body comprises a hinge.
6. The sensor, as set forth in claim 1 , wherein the emitter and the detector are adapted to operate in a transmission mode.
7. The sensor, as set forth in claim 1 , wherein the emitter and the detector are adapted to operate in a reflectance mode.
8. The sensor, as set forth in claim 1 , wherein the sensor body is adapted to allow flexing of an adjacent finger joint when applied to a fingernail region of a finger.
9. The sensor, as set forth in claim 1 , wherein the sensor body comprises a ring adapted to allow flexing of an adjacent finger joint when applied to a finger or toe.
10. The sensor, as set forth in claim 1 , wherein an adhesive is disposed on the sensor body to couple the sensor body to the digit.
11. A pulse oximetry system comprising:
a pulse oximetry monitor; and
a pulse oximetry sensor adapted to be operatively coupled to the monitor, the sensor comprising:
a substantially annular or partially annular rigid sensor body configured to retain the sensor on a patient's digit, wherein the sensor body forms a tissue-contacting surface of the sensor; and
an emitter and a detector disposed on the tissue-contacting surface of sensor body, wherein the sensor body is adapted to hold the emitter and detector at a fixed optical distance relative to one another and relative to the patient's digit when the sensor is attached to a patient and when the digit applies a flexing force to the sensor or when an external tapping force is applied to the sensor.
12. The system, as set forth in claim 11 , wherein the emitter and the detector are adapted to operate in transmission mode.
13. The system, as set forth in claim 11 , wherein the emitter and the detector are adapted to operate in reflectance mode.
14. The system, as set forth in claim 11 , wherein the sensor body is adapted to have an adjustable diameter.
15. The system, as set forth in claim 11 , wherein the sensor body comprises an adjustment strap.
16. The system, as set forth in claim 11 , wherein the sensor body comprises a hinge.
17. A method of manufacturing a pulse oximetry sensor adapted to be applied to a digit, comprising:
providing an annular or partially annular rigid sensor body configured to retain the sensor on the digit and wherein an emitter and a detector are disposed on the tissue-contacting surface of the sensor body, wherein the sensor body is adapted to hold the emitter and the detector at a fixed optical distance relative to each other and relative to the digit when the sensor experiences an external tapping force or when the digit applies a flexing force to the sensor.
18. The method, as set forth in claim 17 , comprising:
providing an adjustment strap.
19. The method, as set forth in claim 17 , comprising:
providing a hinge in the sensor body.
20. The method, as set forth in claim 17 , wherein the emitter and the detector are adapted to operate in transmission mode.
21. The method, as set forth in claim 17 , wherein the emitter and the detector are adapted to operate in reflectance mode.