title: Effect of variation in derived corneal wavefront aberrations by calculation methods on intraocular lens selection.
abstract: OBJECTIVE
  To compare topographically derived corneal wavefront aberrations between the NIDEK Magellan corneal topographer with built-in software (NIDEK Co Ltd) and VOL-CT software (Sarver and Associates) and determine their effects on intraocular lens (IOL) choice based on spherical aberration profiles.
  
  
  METHODS
  Data were collected prospectively for 28 eyes without existing corneal disease prior to undergoing cataract surgery. Corneal higher order aberrations were calculated using Zernike polynomial expansions from topographic data and compared between the builtin NIDEK software and VOL-CT software.
  
  
  RESULTS
  Using two-tailed paired t tests, statistically significant (P<.05) differences were found between the two calculations at 4 mm for 4th order aberrations (NIDEK: 0.2005 μm, VOL-CT: 0.1202 μm) and 6th order aberrations (NIDEK: 0.0985 μm, VOL-CT: 0.0546 μm). Statistically significant differences were noted between the two calculations at 6 mm for 5th order aberrations (NIDEK: 0.2757 μm, VOL-CT: 0.1618 μm) and 6th order aberrations (NIDEK: 0.2641 μm, VOL-CT: 0.0920 μm). No statistically significant differences existed for 3rd order, spherical aberration, and total higher order aberrations. However, using spherical aberration-based IOL selection criteria, the ultimate IOL selection would have differed in 13 eyes if calculated using the NIDEK versus VOL-CT software.
  
  
  CONCLUSIONS
  Statistically significant differences were present in wavefront aberration calculations using the NIDEK versus VOL-CT software for 4- and 6-mm pupil sizes. These differences in spherical aberration could influence wavefront-optimized IOL selection for cataract surgery.
authors.affiliation: Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Massachussetts, USA.
authors.forename: Nicole Hauptman
authors.initials: NH
authors.lastname: Siegel
authors.forename: Wuqaas M
authors.initials: WM
authors.lastname: Munir
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002387:Cataract Extraction; D019781:Corneal Topography / Q000295:instrumentation*; D057108:Corneal Wavefront Aberration / Q000175:diagnosis*; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011680:Pupil / Q000502:physiology; D012984:Software