title: Time-resolved fluorescence of human aortic wall: use for improved identification of atherosclerotic lesions.
abstract: OBJECTIVE
  This study characterized aortic time-resolved fluorescence spectra for stratified levels of atherosclerosis and proposed interpretation of spectrotemporal variations in terms of histologic changes.
  
  
  METHODS
  Fluorescence emission transients were measured at 370-510 nm (337 nm excitation) on 94 excised human aortic samples, ranging from normal to advanced fibrous atherosclerotic lesion. Global analysis yielded a three-exponential approximation of the time-resolved spectra from which average lifetime and decay-associated spectra were derived.
  
  
  RESULTS
  Average lifetime at 390 nm gradually increased from 2.4+/-0.1 nsec (normal aorta) to 3.9+/-0.1 nsec (advanced lesion). Fluorescence intensity was markedly decreased above 430 nm in intermediate and advanced lesions. Spectral intensity associated with the intermediate decay increased at 470-490 nm for early and intermediate lipid-rich lesions.
  
  
  CONCLUSIONS
  Time-resolved fluorescence spectra of aortic samples presented distinctive features for each atherosclerotic lesion type, which could serve as characteristic markers for optical analysis of the aortic wall.
authors.affiliation: Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089, USA. jmaarek@bmsrs.usc.edu
authors.forename: J M
authors.initials: JM
authors.lastname: Maarek
authors.forename: L
authors.initials: L
authors.lastname: Marcu
authors.forename: M C
authors.initials: MC
authors.lastname: Fishbein
authors.forename: W S
authors.initials: WS
authors.lastname: Grundfest
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000473:pathology*; D001161:Arteriosclerosis / Q000175:diagnosis* / Q000473:pathology; D015415:Biomarkers; D002102:Cadaver; D002648:Child; D004730:Endothelium, Vascular / Q000473:pathology*; D006801:Humans; D007834:Lasers; D008875:Middle Aged; D012720:Severity of Illness Index; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013997:Time Factors
chemical_list: D015415:Biomarkers