ROTATING CATHETER PROBE USING A LIGHT-DRIVE APPARATUS

• US 20070239032A1
• Filed: 12/06/2006
• Published: 10/11/2007
• Est. Priority Date: 04/28/2003
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Milner, Thomas, Kemp, Nathaniel
• Granted Patent: US 7,844,321 B2
• Time in Patent Office: Days
• US Class Current: 600/476
• CPC Class Codes: A61B 1/0011 Manufacturing of endoscope parts
• CPC Class Codes: A61B 1/00172 with means for scanning
• CPC Class Codes: A61B 1/00194 adapted for three-dimensional imaging
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

The invention is a rotating tip catheter-imaging probe where electromagnetic energy is delivered to the distal end of a catheter and converted to mechanical energy using a light drive apparatus. The mechanical energy is then used to rotate a mirror that redirects light in fixed pattern on a sample. The rotating element of the light drive apparatus contains vanes, which rotate about an axis and positioned with bearings to minimize friction. A chamber encompasses the rotating element and is set to a vacuum pressure. The rotational speed of the catheter tip can be controlled by varying the optical power delivered to the vanes, the vacuum pressure in the chamber, or by a braking mechanism applied to the rotating element. The vanes may be shaped in a particular geometry to increase forces on the vanes from thermally driven gas flow.

Claims

1. An optical imaging device, comprising

a) a body member having a proximal and a distal end;

b) a optical conduit coaxial with the body member;

c) a reflector element in optical communication with the distal end of the optical conduit;

d) a rotational element operably coupled to the reflector element; and

e) at least one vane member associated with the rotational element and in optical communication with the optical conduit, wherein the vane member includes a thermal gradient between a first surface and a second surface when in optical communication with the optical conduit.

2. The imaging device of claim 1, further comprising a vacuum chamber surrounding at least a portion of the rotational element and the vane member.

3. The imaging device of claim 2, further comprising an anterior bearing operably associated with the reflecting element and a posterior bearing operably associated with the rotational element.

4. The imaging device of claim 3, further comprising a lens in optical communication with the reflector element.

5. The imaging device of claim 3, wherein the reflector element further comprises a dichroic mirror.

6. The imaging device of claim 3, wherein the vane member further comprise radial projections from the rotational element.

7. The imaging device of claim 4, wherein the lens comprises a gradient index lens.

8. The imaging device of claim 3, wherein the rotational element further comprises a capillary tube having an inner lumen in optical communication with the optical conduit, wherein the inner lumen includes a light scattering material directing incident light toward the thermal gradient.

9. The imaging device of claim 3, further comprising means for controlling rotation speed of the rotational element.

10. The imaging device of claim 3, wherein the thermal gradient comprises a first energy absorbing surface and a second energy reflecting surface.

11. A method for directing optical energy for therapeutic or diagnostic purposes, comprising

a) coupling a vane member to a rotatably mounted reflecting element;

b) directing energy to a rotatably mounted vane member within a vacuum sealed chamber;

c) rotating the vane member and the reflecting element by operation of a thermal gradient between the a first surface and a second surface of the vane member;

d) directing energy to the reflecting element.

12. The method of claim 11, further comprising focusing energy to the reflecting element.

13. The method of claim 12, further comprising varying the rotational speed of the vane member.

14. A method of making an optical imaging device, comprising the steps of:

a) providing a body having a central longitudinal lumen extending from a proximal end to a distal end of the body;

b) disposing at least one optical conduit within the central longitudinal lumen of the body; and

c) disposing a rotating reflecting element at a distal end of the body in optical communication with the at least one optical conduit, the rotating reflecting element being coupled to a light drive apparatus in optical communication with at least one optical conduit.

15. The method of claim 14, further comprising positioning a gradient index lens proximal to the rotating reflecting element and in optical communication between at least one optical conduit and the rotating reflecting element.

16. The method of claim 15, wherein the light drive apparatus further comprises mounting a plurality of vane members on a central rotary axle, wherein each of the vane members having a first energy absorbing surface and a second energy reflecting surface.

17. The method of claim 16, wherein the light drive apparatus is made by the steps of:

a) filling an optically transparent tube with a light scattering material having a scattering coefficient sufficient to propagate light along an entire longitudinal length of the optically transparent tube;

b) forming a plurality of radial vanes along the longitudinal length of the optically transparent tube;

c) metallizing the optically transparent tube and plurality of radial vanes with a light reflective metal;

d) removing metallization at least a portion of one side of each of the plurality of radial vanes;

e) applying an electrical charge to the metallization; and

f) depositing a charged energy absorbing material having a charge opposite the applied electrical charge to the metallization to preferentially bind the energy absorbing material to the areas where metallization was removed in step d).