Method and apparatus to prevent infections

• US 6,551,346 B2
• Filed: 03/20/2001
• Issued: 04/22/2003
• Est. Priority Date: 05/17/2000
• Status: Expired due to Term

• Current Assignee: Champion ENT Products, Inc.
• Original Assignee: Kent Crossley
• Inventors: Crossley, Kent
• Primary Examiner(s): Shay, David M
• Application Number:
  US09/812,519
• Publication Number:
  US 20010047195A1
• Time in Patent Office: 763 Days
• Field of Search: 606/1, 606/2, 606/3-7, 606/9-17, 607/88, 607/89, 604/20, 604/22, 604/48, 422/22, 422/24, 422/28, 422/186, 422/186.3
• US Class Current: 607/88
• CPC Class Codes: A61B 2018/2261 with scattering, diffusion or dispersion of light
• CPC Class Codes: A61N 2005/0607 Nose
• CPC Class Codes: A61N 2005/061 Bladder and/or urethra
• CPC Class Codes: A61N 5/0601 Apparatus for use inside the body
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent

Abstract

A photosensitizer together with complementary light energy are used to prevent the development of infection associated with an indwelling medical catheter or device. Light of a selected wavelength or wavelength band is coupled to the catheter or device and transmitted by a wall or walls thereof to one or both of the external and internal surfaces thereof. The catheter or device also incorporates at least one photosensitizer which releases a toxic substance when activated by the light energy which destroys bacteria on or around the catheter or device. A method of preventing infection using photosensitizers and complementary light energy is also disclosed.

Claims

1. Medical apparatus for placement in the human body comprising

a member having an exterior surface adapted for physiological contact;

at least one photosensitizer at or in said exterior surface;

at least one light conductor extending along said member, each light conductor having an input at a proximal location along said member and an output at a distal location along said member, and

a light transmitter for transmitting light energy to said input of the light conductor so that said light energy is conveyed along said member and is emitted at said output so as to illuminate said surface and said photosensitizer(s) residing on or in said exterior surface, the light energy being in a wavelength range to both activate the photosensitizer(s) so as to release toxic oxygen from said surface and also kill microorganisms on or opposite said surface.

2. The apparatus defined in claim 1 wherein said wavelength range is 200 nm to 1400 nm.

3. The apparatus defined in claim 1 wherein said at least one photosensitizer is selected from the group consisting of dimethyl-methylene blue, toluidine blue O, crystal violet, gentian violet, phenothiazinium, phthalocyanines and perylenequinonoids.

4. The apparatus defined in claim 1 wherein the photosensitizer is coated on said surface.

5. The apparatus defined in claim 1 wherein the photosensitizer is imbedded in said member.

6. The apparatus defined in claim 1 wherein the photosensitizer is incorporated in a removable sheath covering said member at said surface.

7. The apparatus defined in claim 1 wherein the apparatus is a nasal applicator and the member comprises a cannula insertable into a nasal passage.

8. The apparatus defined in claim 1 wherein the member comprises a probe.

9. The apparatus defined in claim 1 wherein the member is tubular and at least one light conductor is a spiral light pipe extending along said member and having a plurality of light taps along its length which direct light to said surface.

10. Medical apparatus for placement in the human body comprising

a wall with interior and exterior surfaces;

light energy conductors extending along at least an implantable segment of said wall, said conductors having inputs at a proximal location along said wall and outputs at a distal location along said wall;

at least one photosensitizer on or in said wall segment, said at least one photosensitizer, when illuminated by complementary light energy, releasing activated oxygen radicals which destroy microorganisms, and

a light source for delivering complementary light energy to said inputs so that said complementary light energy is conveyed along said wall segment and is emitted at said outputs thereby illuminating the at least one photosensitizer residing on or in said wall segment and at least one of said surfaces, the complementary light energy being in a wavelength range to both activate the photosensitizer so as to release said oxygen radicals and also kill microorganisms on and opposite said at least one of said surfaces.

11. The apparatus defined in claim 10 wherein said wavelength range is 200 nm to 1400 nm.

12. The apparatus defined in claim 10 wherein said at least one photosensitizer is coated on at least one surface of the wall.

13. The apparatus defined in claim 10 wherein said at least one photosensitizer is coated on both surfaces of the wall.

14. The apparatus defined in claim 10 wherein said at least one photosensitizer is located in said wall.

15. The apparatus defined in claim 10 wherein said at least one photosensitizer is selected from the group consisting of dimethyl-methylene blue, toluidine blue O, crystal violet, gentian violet, phenothiazinium, phthalocyanines and perylenequinonoids.

16. The apparatus defined in claim 10 wherein said wall defines a catheter.

17. The apparatus defined in claim 10 wherein said wall defines a cannula insertable into a nasal passage.

18. The apparatus defined in claim 10 wherein said conductors comprise a plurality of optical fibers extending along said wall, said fibers having output ends directed to at least one of said surfaces.

19. The apparatus defined in claim 18 wherein said fibers extend along the wall between said surfaces thereof.

20. The apparatus defined in claim 18 wherein said fibers extend along the wall at a surface thereof.

21. The apparatus defined in claim 18 wherein said fibers extend along the wall at both surfaces thereof.

22. The apparatus defined in claim 18 wherein said fibers have output ends which are cut on a bias and face said at least one of said surfaces.

23. The apparatus defined in claim 18 wherein said fibers have output ends which are square cut.

24. The apparatus defined in claim 18 wherein the plurality of optical fibers have various lengths.

25. The apparatus defined in claim 18 wherein said optical fibers have one or more light taps along their lengths which face said at least one of said surfaces.

26. The apparatus defined in claim 18 wherein the output ends of said fibers are distributed over substantially the entire surface area of the wall.

27. The apparatus defined in claim 10 wherein said light source is selected from the group consisting of laser, incandescent, fluorescent or halogen bulb and light emitting diode.

28. The apparatus defined in claim 27 wherein the light source is mounted to said wall and connected directly to the inputs of said conductors.

29. The apparatus defined in claim 27 wherein the light includes an illuminator and light pipes extending from said illuminator to the input of said conductors.

30. The apparatus defined in claim 27 wherein said light source is a pulsed source which delivers said light energy as pulses.

31. The apparatus defined in claim 27 wherein said light source is a constant light source which transmits constant light energy.

32. The apparatus defined in claim 10 and further including light scatterers incorporated into said wall for scattering light emitted at the outputs of said conductors.

33. The apparatus defined in claim 32 wherein said light scatterers comprise a multiplicity of tiny fibers selected from the group consisting of plastic, quartz and glass fibers.

34. A method of preventing infections comprising the steps of forming a member with at least one light energy conductor extending along at least a segment of the member, each conductor having an input at a proximal location along the member and an output at a distal location along the member;

incorporating at least one photosensitizer on or in said segment;

placing the segment in the body, and

transmitting light energy to each input so that the light energy is conveyed along the segment and is emitted at the output so as to illuminate a surface of the member, the light energy being in a wavelength range to both activate the photosensitizer residing on or in said segment so as to release toxic oxygen and also kill microorganisms on and opposite the surface.

35. The method defined in claim 34 including the step of selecting the photosensitizers from the group consisting of dimethyl-methylene blue, toluidine blue O, crystal violet, gentian violet, phenothiazinium, phthalocyanines and perylenequinonoids.

36. The method defined in claim 35 including the step of selecting said range between 200 nm and 1400 nm.