title: Higher order aberrations using the NIDEK OPD-Scan and AMO WaveScan.
abstract: OBJECTIVE
  To compare higher order aberrations measured with the NIDEK OPD-Scan and AMO WaveScan.
  
  
  METHODS
  Third- to sixth-order higher order aberrations were measured in 1072 eyes using the OPD-Scan and WaveScan. Means, standard deviations, confidence intervals, limits of agreement, and intraclass correlation coefficients (ICC) were calculated.
  
  
  RESULTS
  Aberrations of greatest magnitude with the OPD-Scan were Z-³/₃ (-0.113 +/- 0.243 μm), Z⁰/₄ (0.073 +/- 0.137 μm), and Z-¹/₃(-0.058 +/- 0.165 μm), and with the WaveScan, 7-³/₃ (-0.054 +/- 0.103 μm), Z⁰/₄ (0.049 +/- 0.083 μm), and Z¹/₃ (-0.017 +/- 0.100 μm). The largest difference in magnitude between the two aberrometers was with Zernike polynomial Z-³/₃ (-0.060 +/- 0.205 μm). Medium consistency (0.6 < ICC < 0.8) was found between the two instruments for Z-¹/₃ and Z⁰/₄. All other Zernike polynomials had a poor consistency (ICC < 0.6) including the total root-mean-square (RMS) higher order aberrations.
  
  
  CONCLUSIONS
  Poor consistency was found for all aberrations except Z-¹/₃and Z⁰/₄, which demostrated medium consistency. Expected aberration reference values are reported for both instruments.
authors.affiliation: School of Biomedical Sciences, University of Ulster, Coleraine, United Kingdom. colm.mcalinden@gmail.com
authors.forename: Colm
authors.initials: C
authors.lastname: McAlinden
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Moore
mesh_terms: D057128:Aberrometry / Q000295:instrumentation*; D000328:Adult; D003315:Cornea / Q000473:pathology*; D057108:Corneal Wavefront Aberration / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult