Atherectomy catheter with aligned imager
An atherectomy catheter is provided for excising and imaging material in a body lumen. In one embodiment, the catheter comprises a catheter body, a cutting blade, and an imaging device. The cutting blade is mounted on the catheter body and configured to move between a first position and a second position relative to an aperture or cutting window. When the cutting blade is in the second position, the blade substantially closes the aperture on the catheter body. The imaging device which is mounted on or otherwise coupled to the cutting blade is configured to be in an imaging position when the cutting blade substantially closes the aperture or cutter window. This allows the imaging device to survey material within the cutting zone of the atherectomy catheter. By allowing the imaging device to view materials within this cutting zone, material may be imaged and then removed from the body lumen without having to reposition the catheter between each step.
1. A method for removing material from a body lumen, the method comprising the steps of:
providing a catheter including a body a cutting window, a cutting blade movable relative to the body, and an imaging device;
introducing the catheter into a body lumen;
advancing the catheter body within the body lumen to position the cutting window at a first location within the body lumen;
imaging an area in the body lumen with the imaging device while the position of the cutting window is maintained at the first location and while the position of the imaging device is maintained at a second location within the body lumen, the second location being spaced longitudinally from the first location within the body lumen; and
cutting material by moving said cutting blade relative to the cutting window.
2. A method as in claim 1 further comprising the step of repositioning the catheter after the imaging step and before the cutting step to cut material in the area.
3. A method as in claim 1 wherein the providing step is carried out with said imaging device being an ultrasound transducer array.
4. A method as in claim 1 wherein the providing step is carried out with said imaging device having at least one optical fiber.
5. A method as in claim 1 wherein the providing step is carried out with said imaging device being an optical coherence tomography device.
6. A method as in claim 1 wherein the imaging step is performed before the cutting step.
7. A method as in claim 1 wherein the imaging step is performed after the cutting step.
8. A method as in claim 1 wherein the imaging device is coupled to the cutting blade.
9. A method as in claim 8 wherein the imaging device is movable relative to the cutting window.
10. A method as in claim 8 wherein the catheter includes a telescoping member which extends from a distal end of the catheter body, the cutting blade being coupled to the telescoping member.
11. A method as in claim 10 wherein the cutting blade includes a proximally pointing cutting edge.
12. A method as in claim 11 wherein the cutting window has a perimeter defined by the distal end of the catheter body and the proximally pointing cutting edge.
13. A method as in claim 12 wherein the proximally pointing cutting edge is moveable from a first position which substantially closes the cutting window to a second position in which the cutting window is open, the proximally pointing cutting edge being contained within the catheter body when the proximally pointing cutting edge is in the first position.
14. A method as in claim 13 wherein the imaging step is performed when the proximally pointing cutting edge is in the first position.
15. A method as in claim 1 wherein the imaging device is coupled to the catheter body.
16. A method as in claim 15 wherein the imaging device is coupled to the catheter body at a location distal to the cutting window.
17. A method as in claim 16 wherein a distance between the cutting window and the imaging device remains constant during the cutting step.
18. A method as in claim 1 wherein during the cutting step the second location is distal to the first location.