title: Problems in the measurement of wavefront aberration for eyes implanted with diffractive bifocal and multifocal intraocular lenses.
abstract: To determine the origin of the wavefront aberration as measured in eyes fitted with diffractive intraocular lenses (IOLs).
  
  
  
  Wavefront aberration was measured by Shack-Hartmann aberrometry in 2 eyes fitted with diffractive bifocal contact lenses and 10 eyes implanted with Acrysof ReSTOR multifocal IOLs.
  
  
  
  Problems were encountered as a result of the multiple wavefronts generated by the diffractive lenses and their dependence on wavelength. These led to ambiguities in the positions of the Shack-Hartmann spot images and in the form of the derived wavefronts.
  
  
  
  Aberrometry may not provide reliable information on the wavefront aberration associated with either the distance or near power of diffractive IOLs.
authors.affiliation: Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: W Neil
authors.initials: WN
authors.lastname: Charman
authors.forename: Robert
authors.initials: R
authors.lastname: Montés-Micó
authors.forename: Hema
authors.initials: H
authors.lastname: Radhakrishnan
mesh_terms: D003261:Contact Lenses; D019781:Corneal Topography / Q000379:methods*; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular / Q000009:adverse effects*; D011474:Prosthesis Design; D019591:Pseudophakia / Q000503:physiopathology; D012030:Refractive Errors / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology