title: Effect of multizone refractive multifocal contact lenses on standard automated perimetry.
abstract: OBJECTIVE
  The aim of this study was to evaluate whether the creation of 2 foci (distance and near) provided by multizone refractive multifocal contact lenses (CLs) for presbyopia correction affects the measurements on Humphreys 24-2 Swedish interactive threshold algorithm (SITA) standard automated perimetry (SAP).
  
  
  METHODS
  In this crossover study, 30 subjects were fitted in random order with either a multifocal CL or a monofocal CL. After 1 month, a Humphrey 24-2 SITA standard strategy was performed. The visual field global indices (the mean deviation [MD] and pattern standard deviation [PSD]), reliability indices, test duration, and number of depressed points deviating at P<5%, P<2%, P<1%, and P<0.5% on pattern deviation probability plots were determined and compared between multifocal and monofocal CLs.
  
  
  RESULTS
  Thirty eyes of 30 subjects were included in this study. There were no statistically significant differences in reliability indices or test duration. There was a statistically significant reduction in the MD with the multifocal CL compared with monfocal CL (P=0.001). Differences were not found in PSD nor in the number of depressed points deviating at P<5%, P<2%, P<1%, and P<0.5% in the pattern deviation probability maps studied.
  
  
  CONCLUSIONS
  The results of this study suggest that the multizone refractive lens produces a generalized depression in threshold sensitivity as measured by the Humphreys 24-2 SITA SAP.
authors.affiliation: Optometry Research Group, Optics Department, University of Valencia, Valencia, Spain. david.madrid@uv.es
authors.forename: David
authors.initials: D
authors.lastname: Madrid-Costa
authors.forename: Javier
authors.initials: J
authors.lastname: Ruiz-Alcocer
authors.forename: Santiago
authors.initials: S
authors.lastname: García-Lázaro
authors.forename: César
authors.initials: C
authors.lastname: Albarrán-Diego
authors.forename: Teresa
authors.initials: T
authors.lastname: Ferrer-Blasco
mesh_terms: D000465:Algorithms; D003261:Contact Lenses; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011305:Presbyopia / Q000503:physiopathology* / Q000628:therapy; D012684:Sensory Thresholds / Q000502:physiology; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields / Q000502:physiology*