Extravascular optical coherence tomography: evaluation of carotid atherosclerosis and pravastatin therapy.

Background and Purpose—Extravascular optical coherence tomography (OCT), as a noninvasive imaging methodology with micrometer resolution, was evaluated in a murine model of carotid atherosclerosis by way of assessing the efficacy of pravastatin therapy. Methods—An OCT device was engineered for extravascular plaque imaging. Wild-type mice and apolipoprotein E–deficient (ApoE−/−) mice were randomized to 3 treatment groups: (1) wild-type on a diet of standard rodent chow (n=13); (2) ApoE−/− on a high-fat, atherosclerotic diet (HFD; n=13); and (3) ApoE−/− on a HFD given daily pravastatin (n=13). Mice were anesthetized and the left common carotid was surgically exposed. Three-dimensional (3D; 2 spatial dimensions+time) and 4D (3 spatial dimensions+time) OCT images of the vessel lumen patency were evaluated. After perfusion, in situ OCT imaging was performed for statistical comparison with the in vivo results and final histology. Results—Intraoperative OCT imaging positively identified carotid plaque in 100% of...