title: The effect of multifocal soft contact lenses on peripheral refraction.
abstract: OBJECTIVE
  To compare changes in peripheral refraction with single-vision (SV) and multifocal (MF) correction of distance central refraction with commercially available SV and MF soft contact lenses (SCLs) in young myopic adults.
  
  
  METHODS
  Thirty-four myopic adult subjects were fitted with Proclear Sphere and Proclear Multifocal SCLs to correct their manifest central refractive error. Central and peripheral refraction were measured with no lens wear and subsequently with the two different types of SCL correction.
  
  
  RESULTS
  At baseline, refraction was myopic at all locations along the horizontal meridian. Peripheral refraction was relatively hyperopic compared with center at 30 and 35 degrees in the temporal visual field (VF) in low myopes, and at 30 and 35 degrees in the temporal VF, and 10, 30, and 35 degrees in the nasal VF in moderate myopes. Single-vision and MF distance correction with Proclear Sphere and Proclear Multifocal SCLs, respectively, caused a hyperopic shift in refraction at all locations in the horizontal VF. Compared with SV correction, MF SCL correction caused a significant relative myopic shift at all locations in the nasal VF in both low and moderate myopes and also at 35 degrees in the temporal VF in moderate myopes.
  
  
  CONCLUSIONS
  Correction of central refractive error with SV and MF SCLs caused a hyperopic shift in both central and peripheral refraction at all positions in the horizontal meridian. Single-vision SCL correction caused the peripheral retina, which initially experienced absolute myopic defocus at baseline with no correction to experience an absolute hyperopic defocus. Multifocal SCL correction resulted in a relative myopic shift in peripheral refraction compared with SV SCL correction. This myopic shift may explain recent reports of reduced myopia progression rates with MF SCL correction.
authors.affiliation: School of Optometry and Vision Science, The University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Pauline
authors.initials: P
authors.lastname: Kang
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Fan
authors.forename: Kelly
authors.initials: K
authors.lastname: Oh
authors.forename: Kevin
authors.initials: K
authors.lastname: Trac
authors.forename: Frank
authors.initials: F
authors.lastname: Zhang
authors.forename: Helen A
authors.initials: HA
authors.lastname: Swarbrick
mesh_terms: D000293:Adolescent; D000328:Adult; D003263:Contact Lenses, Hydrophilic; D018450:Disease Progression; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000503:physiopathology*; D008297:Male; D009216:Myopia / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D012029:Refraction, Ocular / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult