Optical perfusion sensor detector

• US 9,326,711 B2
• Filed: 06/30/2008
• Issued: 05/03/2016
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Kracker, Stefan G., Bhunia, Sourav Kumar
• Primary Examiner(s): EISEMAN, ADAM JARED
• Application Number:
  US12/164,491
• Publication Number:
  US 20090326346A1
• Time in Patent Office: 2,864 Days
• Field of Search: 600322-327, 600331-334, 600336-337, 600339-341, 600/363
• US Class Current: 1/1
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61N 1/37 Monitoring; Protecting

Abstract

A reflectance optical perfusion sensor may include at least one light source and a plurality of detector elements arranged in a planar or nonplanar configuration, such as a three-dimensional array. The detector elements may sense light emitted by the at least one light source and reflected by a blood mass of a patient, such as blood within a blood vessel. In some examples, the detector elements may be arranged such that photodetection surfaces of at least two of the detector elements are nonparallel. In addition to or instead of the nonplanar arrangement of detector elements, an optical perfusion sensor may include a detector array including a plurality of detector elements at least partially surrounding a light source. Varying the location and orientations of detector elements may help increase a quantity of light emitted by the at least one light source and reflected toward the optical perfusion sensor by blood.

Claims

1. An implantable medical device comprising:

an outer housing surface including a first portion configured having a planar profile and a second portion of the surface configured having a curvilinear profile;

a light source disposed on the first portion having an emitter surface oriented in a first plane; and

a plurality of detector elements disposed adjacent to the light source with at least a first of the detector elements being arranged on the first portion and at least a second of the detector elements being arranged on the second portion, each of the detector elements having a photodetection surface and the photodetection surface of the first detector element being oriented in the first plane and the photodetection surface of the second detector element being oriented in a second plane that is different from the first plane, wherein each detector element of the plurality of detector elements is configured to sense a reflection of light that is emitted by the emitter surface and reflected onto the respective detector element.

2. The implantable medical device of claim 1, wherein the plurality of detector elements are arranged in a three-dimensional array of detector elements.

3. The implantable medical device of claim 1, wherein at least a first detector element is arranged in a first spatial position and a second detector element is arranged in a second spatial position that is different from the first spatial position in at least two dimensions.

4. The implantable medical device of claim 1, further comprising a housing that defines a surface comprising a parabolic cross-section, wherein at least some of the plurality of detector elements are coupled to the surface.

5. The implantable medical device of claim 1, wherein at least one of the detector elements comprises a photodiode.

6. The implantable medical device of claim 1, wherein the plurality of detector elements are symmetrically arranged around the light source.

7. The implantable medical device of claim 1, further comprising a housing, wherein the light source and the detector elements are arranged on a common side of the housing.

8. The implantable medical device of claim 7, wherein the housing defines a recess and the light source and the detector elements are disposed in the recess.

9. The implantable medical device of claim 7, wherein the housing defines the surface having the planar profile and the curvilinear profile.

10. The implantable medical device of claim 7, wherein the housing defines a first surface and a second surface, and the light source is coupled to the first surface and at least one of the detector elements of the detector array is coupled to the second surface.

11. The implantable medical device of claim 1, wherein the plurality of detector elements at least partially surround the light source.

12. The implantable medical device of claim 11, wherein the plurality of detector elements surround the light source.

13. The implantable medical device of claim 1, wherein at least two detector elements of the plurality of detector elements have different angular orientations relative to each other.

14. The implantable medical device of claim 1, wherein each detector element of the plurality of detector elements comprises a photodetection surface, wherein the photodetection surfaces of the at least two detector elements are nonparallel.

15. The system implantable medical device of claim 1, wherein the light source comprises at least one of a red light emitting diode or an infrared light emitting diode.

16. The implantable medical device of claim 1, wherein the plurality of detector elements have a fixed position relative to the light source.

26. The implantable medical device of claim 1, wherein the at least one of the photodetection surfaces being oriented at a first angle relative to an axis that is perpendicular to the first plane and a second of the photodetection surfaces being oriented at a second angle that is different from the first angle.

17. An implantable medical device comprising:

an outer housing surface including a first portion configured having a planar profile and a second portion of the surface configured having a curvilinear profile;

a light source disposed on the first portion having an emitter surface oriented in a first plane; and

at least two detectors that are arranged on the surface with a first of the at least two detectors being positioned on the first portion and a second of the at least two detectors being positioned on the second portion adjacent to the first portion, wherein at least a first of the detectors has a photodetection surface that is oriented in the first plane and a second of the detectors is oriented in a second plane that is different from the first plane and each of the at least two detectors is configured to generate a signal indicative of an intensity of a reflection of light emitted by the light source that is reflected onto each detector.

18. The implantable medical device of claim 17, wherein the detectors comprise an annular shape.

19. The implantable medical device of claim 17, wherein the at least two detectors are arranged in a concentric pattern.

20. The implantable medical device of claim 17, wherein the at least two detectors are nonplanar.

21. The implantable medical device of claim 17, wherein the at least two detector elements are arranged in a nonplanar configuration.

22. The implantable medical device of claim 21, wherein the at least two detector elements are arranged in three-dimensional array.

23. The implantable medical device of claim 21, wherein the at least two detector elements are located equidistant from the light source.

24. The implantable medical device of claim 17, wherein a first of the at least two detectors is located on a first side of the light source and a second of the at least two detectors is located on a second side of the light source, wherein the first side is opposite the second side.

25. A method comprising:

transmitting light from a light source positioned on a first outer surface of an implantable medical device housing having a first planar profile; and

receiving the light at a detector positioned on the housing, wherein the detector comprises a plurality of detector elements and at least a first of the detector elements is positioned on the first outer surface on a common plane with the light source and a second of the detector elements is positioned on a second surface having a second profile that is different from the first profile, wherein the second profile includes a plane that is at an angle relative to the plane of the first outer surface.