CHRONIC TOTAL OCCLUSION CROSSING DEVICES WITH IMAGING

1 . A method of crossing an occlusion in a blood vessel, the method comprising:

inserting an occlusion crossing device into the blood vessel, the occlusion crossing device including an outer sheath having an imaging window, wherein an optical fiber extends within a central lumen of the outer sheath, the optical fiber configured to transfer an optical coherence tomography signal, wherein the occlusion crossing device includes a distal cutter;

passing the occlusion crossing device through the occlusion by advancing the occlusion crossing device and contacting the occlusion with the cutter as the cutter is rotating, wherein images of the blood vessel are collected through the imaging window using the optical fiber;

removing the optical fiber from the lumen of the outer sheath; and

advancing a guidewire though the lumen of the outer sheath and the occlusion.

2 . The method of claim 1 , wherein the optical fiber is within a lumen of an imaging shaft.

3 . The method of claim 2 , wherein the distal cutter is coupled to a distal end of the imaging shaft.

4 . The method of claim 2 , further comprising a mirror within the lumen of the imaging shaft, the mirror configured to reflect light from the optical fiber through the imaging window and toward adjacent tissue.

5 . The method of claim 1 , wherein the cutter is rotated at speeds of greater than 1,000 rotations per minute (rmp).

6 . The method of claim 1 , wherein the images of the blood vessel are collected at rates of greater than 10 frames per minute.

7 . The method of claim 1 , further comprising rotating the optical fiber with the hollow flexible shaft.

8 . The method of claim 1 , wherein the distal cutter includes multiple sharp flutes that come to a point.

9 . The method of claim 1 , wherein the blood vessel is a coronary artery.

10 . The method of claim 1 , wherein the blood vessel is a peripheral artery.

11 . An occlusion crossing device comprising:

an outer sheath having a central lumen and an imaging window;

optical fiber extends within the central lumen of the outer sheath, the optical fiber configured to transfer an optical coherence tomography signal through the imaging window of the outer sheath, wherein the optical fiber is removable from the central lumen of the outer sheath such that a guidewire can be advanced through the central lumen of the outer sheath after removal of the optical fiber; and

a distal cutter configured to rotate with respect to the outer sheath.

12 . The occlusion crossing device of claim 11 , wherein the optical fiber is within a lumen of an imaging shaft.

13 . The occlusion crossing device of claim 12 , wherein the distal cutter is coupled to a distal end of the imaging shaft.

14 . The occlusion crossing device of claim 12 , further comprising a mirror within the lumen of the imaging shaft, the mirror configured to reflect light from the optical fiber through the imaging window and toward adjacent tissue.

15 . The occlusion crossing device of claim 11 , wherein the device is less than 0.1 inches in diameter.

16 . The occlusion crossing device of claim 11 , wherein the device is less than 0.08 inches in diameter.

17 . The occlusion crossing device of claim 11 , wherein the device is less than 0.05 inches in diameter.

18 . The occlusion crossing device of claim 11 , wherein the distal cutter is configured to rotate at speeds of greater than 1,000 rotations per minute (rmp).

19 . The occlusion crossing device of claim 11 , wherein the occlusion crossing device is configured to collect images of the blood vessel at rates of greater than 10 frames per minute.

20 . The occlusion crossing device of claim 11 , wherein the distal cutter includes multiple sharp flutes that come to a point.