title: Diagnosis of human coronary atherosclerosis by morphology-based Raman spectroscopy.
abstract: BACKGROUND
  Recent studies have shown that chemical composition and morphology, rather than anatomy (degree of stenosis), determine atherosclerotic plaque instability and predict disease progression. Current clinical diagnostic techniques provide accurate assessment of plaque anatomy, but have limited capability to assess plaque morphology in vivo. Here we describe a technique for a morphology-based diagnosis of atherosclerosis in the coronary arteries using Raman spectroscopy that can potentially be performed in vivo using optical fiber technology.
  
  
  METHODS
  Raman tissue spectra were collected from normal and atherosclerotic coronary artery samples in different stages of disease progression (n=165) from explanted transplant recipient hearts (n=16). Raman spectra from the elastic laminae (EL), collagen fibers (CF), smooth muscle cells (SMC), adventitial adipocytes (AA) or fat cells, foam cells (FC), necrotic core (NC), cholesterol crystals (CC), beta-carotene containing crystals (beta-C), and calcium mineralizations (CM) were used as basis spectra in a linear least squares-minimization (LSM) model to calculate the contribution of these morphologic structures to the coronary artery tissue spectra.
  
  
  RESULTS
  We developed a diagnostic algorithm that used the fit-contributions of the various morphologic structures to classify 97 coronary artery samples in an initial calibration data set as either nonatherosclerotic, calcified plaque, or noncalcified atheromatous plaque. The algorithm was subsequently tested prospectively in a second validation data set, and correctly classified 64 (94%) of 68 coronary artery samples.
  
  
  CONCLUSIONS
  Raman spectroscopy provides information about the morphologic composition of intact human coronary artery without the need for excision and microscopic examination. In the future, it may be possible to use this technique to analyze the morphologic composition of atherosclerotic coronary artery lesions and assess plaque instability and disease progression in vivo.
authors: Leiden University Medical Center, Leiden, Netherlands. r.buschman@rrd.nl
authors: H P
authors: HP
authors: Buschman
authors: J T
authors: JT
authors: Motz
authors: G
authors: G
authors: Deinum
authors: T J
authors: TJ
authors: Römer
authors: M
authors: M
authors: Fitzmaurice
authors: J R
authors: JR
authors: Kramer
authors: A
authors: A
authors: van der Laarse
authors: A V
authors: AV
authors: Bruschke
authors: M S
authors: MS
authors: Feld
mesh_terms: D017667:Adipocytes / Q000737:chemistry; D000273:Adipose Tissue / Q000737:chemistry; D000465:Algorithms; D002114:Calcinosis / Q000378:metabolism; D002118:Calcium / Q000032:analysis; D002784:Cholesterol / Q000032:analysis; D003094:Collagen / Q000737:chemistry; D003324:Coronary Artery Disease / Q000145:classification / Q000175:diagnosis* / Q000378:metabolism; D003331:Coronary Vessels / Q000737:chemistry / Q000473:pathology*; D003460:Crystallization; D018450:Disease Progression; D004547:Elastic Tissue / Q000737:chemistry; D005487:Foam Cells / Q000737:chemistry; D006801:Humans; D018613:Microscopy, Confocal / Q000379:methods; D009130:Muscle, Smooth / Q000737:chemistry / Q000166:cytology; D009336:Necrosis; D013059:Spectrum Analysis, Raman / Q000379:methods*; D019207:beta Carotene / Q000032:analysis
chemical_list: D019207:beta Carotene; D003094:Collagen; D002784:Cholesterol; D002118:Calcium