title: From bench to bedside: a novel technique of acquiring OCT images.
abstract: BACKGROUND
  Optical coherence tomography (OCT), a high resolution intravascular imaging technique, requires blood displacement for reliable image acquisition and the current technique uses a soft occlusion balloon plus saline injection in the coronary artery. A non-occlusive technique based on manual infusion of a viscous iso-osmolar solution has been developed and tested and validated through a 2-phase study.
  
  
  RESULTS
  OCT assessment was performed with the M2 LightLab OCT (LightLab Imaging, Westford, MA, USA) image-wire in 3 swine by infusing 30 ml of each of 3 solutions differing in viscosity, osmolarity and electrolytic composition (A: iodixanol 320 and Lactated Ringer's; B: iodixanol 320 and 50% albumin; C: iodixanol 320). Image quality and adverse effects were evaluated. The solution with the best image quality/side-effect ratio was tested in 44 patients. The best image quality/side-effect ratio was obtained in the swine model with solution C, which enabled the study of arterial segments of 29.8+/-2.1 mm in length. The results were confirmed in the human study (average length of 28.3+/-2.5 mm and absence of major complications and/or major arrhythmias). Repeated OCT pull-back in the first 10 patients enabled comparison of 1,572 matched cross-sections with an excellent correlation for reproducibility (R=0.96; p<0.001).
  
  
  CONCLUSIONS
  The non-occlusive technique using iodixanol 320 has an excellent ratio of safety, feasibility and efficacy.
authors.affiliation: Interventional Cardiology, San Giovanni Hospital, Rome, Italy. fprati@hsangiovanni.roma.it
authors.forename: Francesco
authors.initials: F
authors.lastname: Prati
authors.forename: Maria
authors.initials: M
authors.lastname: Cera
authors.forename: Vito
authors.initials: V
authors.lastname: Ramazzotti
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Imola
authors.forename: Rocco
authors.initials: R
authors.lastname: Giudice
authors.forename: Marco
authors.initials: M
authors.lastname: Giudice
authors.forename: Silvia De
authors.initials: SD
authors.lastname: Propris
authors.forename: Mario
authors.initials: M
authors.lastname: Albertucci
mesh_terms: D000368:Aged; D000418:Albumins; D000818:Animals; D050197:Atherosclerosis / Q000175:diagnosis*; D003287:Contrast Media / Q000494:pharmacology; D005260:Female; D006801:Humans; D007552:Isotonic Solutions; D008297:Male; D008875:Middle Aged; D023421:Models, Animal; D015203:Reproducibility of Results; D000077325:Ringer's Lactate; D013552:Swine; D041623:Tomography, Optical Coherence / Q000379:methods* / Q000592:standards*; D014283:Triiodobenzoic Acids
chemical_list: D000418:Albumins; D003287:Contrast Media; D007552:Isotonic Solutions; D000077325:Ringer's Lactate; D014283:Triiodobenzoic Acids; C044834:iodixanol