Imaging system includes imaging probe and delivery devices

1. A method for treating a patient, comprising:

providing an imaging system comprising:

a first delivery catheter comprising a lumen therethrough and an expandable balloon;

an imaging probe comprising:

an elongate shaft comprising a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion;

a rotatable optical core positioned within the lumen of the elongate shaft and comprising a proximal end and a distal end, the rotatable optical core configured to optically and mechanically connect with an interface unit; and

an optical assembly positioned in the distal portion of the elongate shaft and proximate the rotatable optical core distal end, the optical assembly configured to direct light to tissue and collect reflected light from the tissue;

wherein the imaging probe is constructed and arranged to collect image data from a patient site based on the directed light and the reflected light;

a rotating assembly constructed and arranged to rotate the optical assembly; and

a retraction assembly constructed and arranged to retract the optical assembly; and

an injectate;

wherein the first delivery catheter is inserted into the patient and advanced to a first anatomical location;

wherein the balloon of the first delivery catheter is inflated; and

wherein the injectate is delivered through the first delivery catheter.

2. The method according to claim 1 , wherein the first delivery catheter comprises a delivery catheter of approximately between 8 Fr and 9 Fr.

3. The method according to claim 1 , wherein the imaging system further comprises a second delivery catheter comprising a lumen therethrough.

4. The method according to claim 3 , wherein the second delivery catheter is inserted into the lumen of the first delivery catheter.

5. The method according to claim 4 , wherein the injectate is delivered through the second delivery catheter.

6. The method according to claim 1 , wherein the injectate comprises fluid selected from the group consisting of: optically transparent material; saline; visualizable material; contrast; Dextran; an ultrasonically reflective material; a magnetic material; and combinations thereof.

7. The method according to claim 1 , wherein the injectate is delivered during a flushing procedure configured to remove non-transparent material proximate the optical assembly.

8. The method according to claim 7 , wherein the non-transparent material is blood.

9. The method according to claim 1 , wherein the injectate is delivered at a rate between 3 ml/second and 6 ml/second.

10. The method according to claim 1 , wherein the injectate is delivered at a rate between 2 ml/second and 3 ml/second.

11. The method according to claim 10 , wherein the injectate comprises contrast mixed with saline.

12. The method according to claim 10 , wherein the injectate is delivered for between 2 seconds and 8 seconds.

13. The method according to claim 12 , wherein the injectate is delivered for approximately 4 seconds.

14. The method according to claim 10 , wherein the injectate is delivered with an approximate flow profile selected from the group consisting of: contrast mixed with saline at 5 ml/second for 6 seconds; contrast mixed with saline at 4 ml/second for 6 seconds; and combinations thereof.

15. The method according to claim 1 , wherein a volume of injectate delivered and/or a time of injectate delivery during is determined by a parameter selected from the group consisting of: type of procedure being performed; diameter of vessel in which the optical assembly is positioned; length of a pullback procedure; duration of a pullback procedure; and combinations thereof.

16. The method according to claim 1 , wherein the injectate comprises a material configured to be viewed by an imaging device.

17. The method according to claim 1 , wherein the injectate is delivered based on a parameter selected from the group consisting of: a pre-determined volume of injectate to be delivered; a pre-determined time during which injectate is delivered; an amount of time of delivery; and combinations thereof.

18. The method according to claim 1 , wherein the elongate shaft distal portion comprises a viewing portion that surrounds the optical assembly.

19. The method according to claim 1 , wherein one or more portions of the elongate shaft proximal to the optical assembly include a non-transparent construction.

20. The method according to claim 1 , wherein the retraction assembly retracts the optical assembly and the elongate shaft at a retraction rate between 5 mm/second and 60 mm/second.

21. The method according to claim 20 , wherein the retraction rate is approximately 40 mm/second.

22. The method according to claim 1 , wherein the retraction assembly performs a pullback procedure comprising a retraction of the optical assembly and the elongate shaft.

23. The method according to claim 22 , wherein the pullback procedure comprises a retraction distance between 20 mm and 100 mm.

24. The method according to claim 23 , wherein the pullback procedure is performed during a time period of between 1 second and 15 seconds.