Identification of elastic lamina to guide interventional therapy
Described herein is a system and method for identifying elastic lamina during interventional procedures, such as atherectomy. Such identification can be used to avoid trauma to the external elastic lamina during the procedure.
1. A method of performing atherectomy, comprising:
inserting an atherectomy device into a vessel of a patient;
gathering optical coherence tomography (OCT) images using an imaging sensor on the device;
identifying an external elastic lamina (EEL) of a wall of the vessel in the OCT images;
orienting a cutter of the atherectomy device away from the EEL based upon the identifications;
adjusting a depth of cut based upon the identification; and
removing plaque from the wall of the vessel with the cutter while the cutter is oriented away from the EEL;
wherein the device further includes a balloon configured to inflate or deflate to expose or cover the cutter, and wherein moving the cutter from an active mode to a passive mode comprises at least partially deflating the balloon.
2. The method of claim 1 , wherein orienting the cutter of the atherectomy device away from the EEL comprises moving the cutter from a direction normal to the EEL to a direction towards the plaque.
3. The method of claim 1 , further comprising determining from the OCT images whether trauma to the EEL has occurred.
4. The method of claim 3 , further comprising adjusting a treatment plan to mitigate an inflammatory cascade caused by the trauma to the EEL.
5. The method of claim 4 , wherein adjusting the treatment plan comprises implanting a drug coated stent in the vessel, implanting a drug eluting balloon in the vessel, or providing an oral medication to the patient.
6. The method of claim 1 , wherein the OCT images are a toroidal view of the vessel.
7. The method of claim 6 , wherein the step of identifying an EEL further comprises identifying an outer-most bright line in the toroidal view.
8. The method of claim 1 , wherein the adjusting step is performed automatically.
9. The method of claim 1 , further comprising determining a distance between the cutter and the EEL.
10. The method of claim 9 , further comprising activating an alarm if the distance is below a threshold value.
11. The method of claim 9 , further comprising stopping removing plaque if the distance is below a threshold value.