LIGHT GENERATING DEVICE FOR INTRAVASCULAR USE

• US 20080033519A1
• Filed: 08/06/2007
• Published: 02/07/2008
• Est. Priority Date: 03/14/2003
• Status: Active Grant

• Current Assignee: Light Sciences Oncology, Inc.
• Original Assignee: Light Sciences Oncology, Inc.
• Inventors: Yeo, Nick, Narciso, Hugh, Burwell, Phillip, Lichttenegger, Gary, Guo, Zihong, Bishop, Jean, Daly, Steven, Shine, David, Matson, Jennifer
• Granted Patent: US 10,376,711 B2
• Time in Patent Office: Days
• US Class Current: 607/122
• CPC Class Codes: A61B 2018/2261 with scattering, diffusion or dispersion of light
• CPC Class Codes: A61N 2005/0602 for treatment of blood vessels
• CPC Class Codes: A61N 2005/063 comprising light transmitting means, e.g. optical fibres
• CPC Class Codes: A61N 2005/0652 Arrays of diodes
• 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

Light sources are incorporated into a guidewire for enabling the ability to render light therapy be added to catheters that do not have that capability. In one exemplary embodiment, a solid guidewire includes a conductive core, and light sources are added to compartments formed in a distal end of the guidewire. In another exemplary embodiment, a light source array is included in a distal end of a hollow guidewire. A plurality of openings are formed into the walls of the hollow guidewire surrounding the array, enabling light to pass through the openings. Conductors extend from the array though the hollow center of the guidewire, to a proximal end of the hollow guidewire. The hollow guidewire can be coated with a conductive material, so that the coating on the guidewire serves as a conductor.

Claims

1. A method for using photodynamic therapy to treat vascular tissue, comprising the steps of:

(a) providing a vascular illumination apparatus comprising a guidewire, the guidewire including;

(i) at least one light source element disposed at a distal end of the guidewire, the at least one light source element, when energized, emitting light having a characteristic emission waveband; and

(ii) at least one conductor configured to couple the at least one light source to a power supply to enable the at least one light source element to be energized;

(b) administering a photoreactive agent to target vascular tissue in a patient, the photoreactive agent having a characteristic absorption waveband corresponding to the characteristic emission waveband of the at least one light source element;

(c) advancing the vascular illumination apparatus through the vascular system of the patient until the at least one light source element is disposed adjacent to the vascular target tissue; and

(d) energizing the at least one light source element to administer light to the vascular target tissue, the application of light to the vascular target tissue resulting in at least one of a therapeutic effect and generation of diagnostic data.

2. The method of claim 1, wherein before the step of energizing the light source element, further comprising the step of centering the vascular illumination apparatus within a blood vessel that includes the vascular target tissue, using a catheter including an expandable member that is advanced along the guidewire until the expandable member is proximate to the vascular target tissue, the expandable member centering the guidewire in the blood vessel.

3. The method of claim 2, wherein before the step of energizing the light source element, further comprising the step of displacing a bodily fluid disposed between the light source element and the vascular target tissue, thereby preventing the bodily fluid from interfering with the transmission of light from the light source element to the target tissue.

4. The method of claim 3, wherein the step of displacing the bodily fluid disposed between the light source element and the target tissue before the step of energizing the light source element comprises the steps of:

(a) positioning the expandable member so that it substantially encompasses the at least one light source element; and

(b) expanding the expandable member until the expandable member contacts the walls of the vascular lumen adjacent to the target tissue, thereby displacing bodily fluid that could interfere with the transmission of light from the at least one light source element to the target tissue.

5. A method of making a guidewire including at least one light source, comprising the steps of:

(a) incorporating at least one light source into a distal end of the guidewire; and

(b) extending electrical conductors from the at least one light source to a proximal end of the guidewire, so that the electrical conductors can be used to selectively energize the at least one light source, when a proximal end of the electrical conductors are coupled to a source of electrical power.

6. The method of claim 5, wherein the step of extending electrical conductors from the at least one light source to a proximal end of the guidewire comprises the step of incorporating a conductive core into a solid guidewire, the conductive core extending from the distal end of the guidewire to a proximal end of the guidewire.

7. The method of claim 6, wherein the step of incorporating at least one light source into the distal end of the guidewire comprises the steps of:

(a) forming a compartment into the distal end of the guidewire, the compartment extending from an outer surface of the guidewire to the conductive core; and

(b) inserting the at least one light source into the compartment, such that the at least one light source is electrically coupled to the conductive core.

8. The method of claim 7, wherein a plurality of light sources are employed to emit light, and each of the plurality of light sources is introduced into a corresponding separate compartment.

9. The method of claim 8, wherein the plurality of corresponding separate compartments are of sufficient size and distribution so as to collectively function as a strain relief feature and are arranged in at least one configuration selected from the group consisting essentially of:

(a) a linear array; and

(b) a distribution around a periphery of the guidewire, such that light can be emitted from the guidewire in a plurality of different directions.

10. The method of claim 5, wherein the step of incorporating at least one light source into the distal end of the guidewire comprises the steps of:

(a) providing a hollow guidewire;

(b) forming a plurality of openings in a distal end of the hollow guidewire; and

(c) inserting a light source array into the distal end of the hollow guidewire, such that light from the light source array can pass through the plurality of openings.

11. The method of claim 10, wherein the step of forming a plurality of openings in a distal end of the hollow guidewire comprises the step of removing at least about seventy five percent of the guidewire from an area defining the plurality of openings.

12. The method of claim 10, further comprising the step of encapsulating the light source array in a potting material that is electrically insulating and substantially optically transparent to light emitted from the light source array.

13. The method of claim 10, wherein the step of extending electrical conductors from the at least one light source to the proximal end of the guidewire comprises the step of extending electrical conductors from the light source array to the proximal end of the guidewire via a central lumen in the guidewire.

14. The method of claim 13, wherein the step of extending electrical conductors from the at least one light source to the proximal end of the guidewire comprises the steps of:

(a) coating a surface of the guidewire with a conductive material, so that the coated surface of the guidewire functions as a first electrical conductor; and

(b) extending a wire from the light source array to the proximal end of the guidewire via a central lumen in the guidewire, so the wire functions as a second electrical conductor.

15. The method of claim 14, wherein the step of coating the surface of the guidewire with the conductive material comprises the step of coating an interior surface of the guidewire.

16. A light emitting guidewire comprising at least one light source disposed at a distal end of the guidewire, and a conductive path configured to electrically couple the at least one light source to an external power supply.

17. The light emitting guidewire of claim 16, wherein the guidewire is substantially solid, and the conductive path comprises a conductive core.

18. The light emitting guidewire of claim 17, wherein the guidewire comprises at least one compartment formed into the distal end of the guidewire, the compartment being sized and shaped to accommodate the at least one light source.

19. The light emitting guidewire of claim 18, wherein the at least one light source comprises a plurality of light sources, and the at least one compartment comprises a plurality of compartments, such that each different light source is disposed in a corresponding different compartment.

20. The light emitting guidewire of claim 19, wherein the plurality of compartments are configured to function as a strain relief feature, to enhance a flexibility of the guidewire.

21. The light emitting guidewire of claim 16, wherein the guidewire comprises a hollow tube, the hollow tube including a plurality of openings disposed proximate to the distal end of the guidewire, the at least one light source comprising a light source array disposed within the hollow tube, such that the plurality of openings encompass the array.

22. The light emitting guidewire of claim 21, wherein the array is encapsulated in a potting material that is electrically insulating and optically transparent to the light emitted by the array.

23. The light emitting guidewire of claim 21, wherein the hollow tube is coated with a conductive material, such that the conductive path includes a first electrical conductor comprising the conductive material coating and a second electrical conductor comprising a wire.

24. The light emitting guidewire of claim 23, wherein the conductive material coating is disposed inside the hollow tube.

25. The light emitting guidewire of claim 21, wherein the conductive path includes a first wire and a second wire, the first and second wires extending inside the hollow tube from the array to a proximal end of the hollow tube.