title: Frequency-domain intravascular optical coherence tomography of the femoropopliteal artery.
abstract: OBJECTIVE
  Optical coherence tomography (OCT) is a catheter-based imaging method that employs near-infrared light to produce high-resolution intravascular images. The authors report the safety and feasibility and illustrate common imaging findings of frequency-domain OCT (FD-OCT) imaging of the femoropopliteal artery in a series of 20 patients who underwent infrainguinal angioplasty.
  
  
  METHODS
  After crossing the lesion of interest, OCT was performed with a dextrose saline flush technique with simultaneous obstructive manual groin compression. An automatic pullback FD-OCT device was employed (each scan acquiring 54 mm of vessel lumen in 271 consecutive frames). OCT images were acquired before and after balloon dilatation and following provisional stenting if necessary and were evaluated for baseline characteristics of plaque or in-stent restenosis (ISR), vessel wall trauma after angioplasty, presence of thrombus, stent apposition, and tissue prolapse. Imaging follow-up was not included in this study's protocol.
  
  
  RESULTS
  Twenty-seven obstructive lesions (18 cases of de novo atherosclerosis and 9 of ISR) of the femoropopliteal artery were imaged and 148 acquisitions were analyzed in total. High-resolution intravascular OCT imaging with effective blood clearance was achieved in 93.9%. Failure was mainly attributed to preocclusive proximal lesions and/or collateral flow. Mixed features of lipid pool areas, calcium deposits, necrotic core, and fibrosis were identified in all of the imaged atherosclerotic lesions, whereas ISR was purely fibrotic. After balloon angioplasty, OCT identified extensive intimal tears in all cases and one case of severe dissection that biplane subtraction angiography failed to identify.
  
  
  CONCLUSIONS
  Infrainguinal frequency-domain optical coherence tomography is safe and feasible and may provide intravascular high-resolution imaging of the femoropopliteal artery during infrainguinal angioplasty procedures.
authors.affiliation: Department of Radiology, School of Medicine, Patras University Hospital, Patras 26504, Greece. karnaby@upatras.gr
authors.forename: Dimitris
authors.initials: D
authors.lastname: Karnabatidis
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Katsanos
authors.forename: Ioannis
authors.initials: I
authors.lastname: Paraskevopoulos
authors.forename: Athanasios
authors.initials: A
authors.lastname: Diamantopoulos
authors.forename: Stavros
authors.initials: S
authors.lastname: Spiliopoulos
authors.forename: Dimitris
authors.initials: D
authors.lastname: Siablis
mesh_terms: D015901:Angiography, Digital Subtraction; D001157:Arterial Occlusive Diseases / Q000175:diagnosis* / Q000628:therapy*; D002404:Catheterization; D005240:Feasibility Studies; D005260:Female; D005263:Femoral Artery; D006801:Humans; D008297:Male; D011150:Popliteal Artery; D018709:Statistics, Nonparametric; D015607:Stents; D041623:Tomography, Optical Coherence / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional