title: Performance of wavefront-guided soft lenses in three keratoconus subjects.
abstract: OBJECTIVE
  To examine whether custom wavefront-guided soft contact lenses provide visual and optical performance equivalent to habitual gas permeable (GP) corrections in three keratoconus subjects.
  
  
  METHODS
  Custom wavefront-guided soft contact lenses were produced and evaluated at the Visual Optics Institute, College of Optometry, University of Houston for three habitual GP-wearing keratoconus subjects. Photopic high and mesopic low contrast logarithm of minimum angle of resolution visual acuity (logMAR VA) and residual second to tenth order optical aberrations experienced with these custom soft lenses were recorded and compared with the subjects' habitual GP correction.
  
  
  RESULTS
  All three subjects wearing custom soft lenses reached the established exit criterion of photopic high contrast (HC) logMAR VA equal to or better than values recorded with their habitual GP lens. HC logMAR VA for GP and custom soft lens correction was 0.01 +/- 0.05 and 0.00 +/- 0.02 for KC1, 0.20 +/- 0.02 and 0.14 +/- 0.02 for KC2, and 0.04 +/- 0.09 and -0.05 +/- 0.05 for KC3, respectively. In addition, KC2 reached the exit criterion of high-order aberration levels equal to or less than values with their habitual GP lens (GP lens: 0.394 +/- 0.024 microm, custom lens: 0.381 +/- 0.074 microm).
  
  
  CONCLUSIONS
  Custom wavefront-guided soft contact lenses have been demonstrated to provide equivalent photopic HC logMAR VA to that achieved with habitual GP correction in three keratoconus subjects. Future emphasis will be placed on surpassing habitual GP performance and reaching a normal age-matched criterion for both VA and aberration measures. Achieving these goals may require a more thorough understanding of the relationship between visual performance and residual aberration experienced during custom lens wear through the use of image quality metrics predictive of visual performance.
authors.affiliation: Visual Optics Institute, College of Optometry, University of Houston, Houston, Texas 77204, USA. jmarsack@optometry.uh.edu
authors.forename: Jason D
authors.initials: JD
authors.lastname: Marsack
authors.forename: Katrina E
authors.initials: KE
authors.lastname: Parker
authors.forename: Raymond A
authors.initials: RA
authors.lastname: Applegate
mesh_terms: D000328:Adult; D000369:Aged, 80 and over; D001251:Astigmatism / Q000503:physiopathology / Q000628:therapy; D003263:Contact Lenses, Hydrophilic / Q000706:statistics & numerical data*; D015350:Contrast Sensitivity; D003315:Cornea / Q000002:abnormalities / Q000503:physiopathology; D004867:Equipment Design; D006801:Humans; D007640:Keratoconus / Q000503:physiopathology / Q000628:therapy*; D007908:Lens, Crystalline / Q000503:physiopathology; D012030:Refractive Errors / Q000503:physiopathology / Q000628:therapy; D014792:Visual Acuity