title: Intrinsic versus laser-induced fluorescence spectroscopy for coronary atherosclerosis: a generational comparison model for testing diagnostic accuracy.
abstract: Laser-induced fluorescence (LIF) and intrinsic fluorescence spectroscopy (IFS) have been used experimentally for diagnosing coronary atherosclerosis. In this study, we demonstrated the diagnostic superiority of IFS at 342-nm excitation (IFS(342)) versus LIF (LIF(342))  and described a protocol for head-to-head comparison of old (LIF) versus new (IFS) generations of similar diagnostic methods, labeled as "generational comparison model". IFS(342) and LIF(342) were modeled with basis spectra of media, fibrous caps, and superficial  foam cells and of their correspondent chemicals (elastin, collagen, and lipoproteins). The average accuracy and receiver operating characteristic area under the curve of IFS(342) in single-, double-, and triple-parameter diagnostic algorithm iterations, geared toward identifying 84  atherosclerotic specimens from a group of 117 coronary segments, was 90% ± 1% and 0.87 ± 0.025, superior to LIF(342) (84% ± 3% and 0.84 ± 0.016; P = 0.0002 and 0.02, respectively) in a generational comparison model.
authors.affiliation: Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. goangheloiu@drmc.org
authors.forename: George O
authors.initials: GO
authors.lastname: Angheloiu
authors.forename: Sweder W E
authors.initials: SW
authors.lastname: van de Poll
authors.forename: Irene
authors.initials: I
authors.lastname: Georgakoudi
authors.forename: Jason T
authors.initials: JT
authors.lastname: Motz
authors.forename: Abigail S
authors.initials: AS
authors.lastname: Haka
authors.forename: Eugene
authors.initials: E
authors.lastname: Podrez
authors.forename: Maryann
authors.initials: M
authors.lastname: Fitzmaurice
authors.forename: Ramachandra R
authors.initials: RR
authors.lastname: Dasari
authors.forename: Michael S
authors.initials: MS
authors.lastname: Feld
authors.forename: John R
authors.initials: JR
authors.lastname: Kramer
mesh_terms: D000465:Algorithms; D003094:Collagen / Q000737:chemistry; D003324:Coronary Artery Disease / Q000175:diagnosis*; D003331:Coronary Vessels / Q000737:chemistry; D003952:Diagnostic Imaging / Q000379:methods*; D004549:Elastin / Q000737:chemistry; D005487:Foam Cells / Q000737:chemistry; D006801:Humans; D007834:Lasers; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D003094:Collagen; D004549:Elastin