title: Does optical coherence tomography identify arterial healing after stenting? An in vivo comparison with histology, in a rabbit carotid model.
abstract: OBJECTIVE
  To verify whether optical coherence tomography (OCT) can accurately monitor the occurrence of arterial healing after stenting.
  
  
  METHODS
  Delayed stent endothelialisation may predispose to stent thrombosis. OCT is a high-resolution intravascular imaging technique that accurately identifies stent struts and arterial tissues.
  
  
  METHODS
  Eight New Zealand white rabbits underwent the implantation of single bare metal stents (diameter 2-2.5 mm, length 8-13 mm) in the right common carotid artery through the external carotid artery. After a median of 11 days (range 2-28), the stented arteries were visualised by OCT, with images acquired at a pull-back speed of 0.5 mm/sec. The rabbits were then euthanised, vessels were formalin-fixed and finally processed for histopathology.
  
  
  RESULTS
  We analysed 32 cross-sections from eight stented carotid arteries, for a total of 384 stent struts. OCT detected all of the stent struts in 30 of 32 cross-sections (93.7%), and correctly identified the presence/absence of tissue for every strut. Histological and OCT measurements of mean neointima thickness (0.135 (SD 0.079) mm and 0.145 (SD 0.085) mm, respectively, p = NS) were similar and closely related (r = 0.85, p<0.001). Neointima area progressively increased with longer time intervals from stent deployment to sacrifice; histological and OCT measurements were similar for each time interval. The intra-observer and interobserver reproducibility of OCT neointima measurements were excellent (R2 = 0.90 and 0.88, respectively).
  
  
  CONCLUSIONS
  OCT is a promising means for monitoring stent strut coverage and vessel wall healing in vivo, the relevance of which will become even more significant with the increasing use of drug-eluting stents.
authors.affiliation: Interventional Cardiology, San Giovanni-Addolorata Hospital, Rome, Italy. fprati@hsangiovanni.roma.it
authors.forename: F
authors.initials: F
authors.lastname: Prati
authors.forename: M
authors.initials: M
authors.lastname: Zimarino
authors.forename: E
authors.initials: E
authors.lastname: Stabile
authors.forename: G
authors.initials: G
authors.lastname: Pizzicannella
authors.forename: T
authors.initials: T
authors.lastname: Fouad
authors.forename: R
authors.initials: R
authors.lastname: Rabozzi
authors.forename: A
authors.initials: A
authors.lastname: Filippini
authors.forename: J
authors.initials: J
authors.lastname: Pizzicannella
authors.forename: M
authors.initials: M
authors.lastname: Cera
authors.forename: R
authors.initials: R
authors.lastname: De Caterina
mesh_terms: D000818:Animals; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging* / Q000473:pathology; D011817:Rabbits; D011859:Radiography; D015607:Stents; D041623:Tomography, Optical Coherence; D017539:Tunica Intima / Q000473:pathology; D014945:Wound Healing