title: Corneal changes and wavefront analysis after orthokeratology fitting test.
abstract: OBJECTIVE
  To evaluate corneal changes and ocular aberrations during an orthokeratology test.
  
  
  METHODS
  A prospective, nonrandomized cohort study.
  
  
  METHODS
  Fourteen myopic patients (26 eyes) underwent an orthokeratology fitting test with the BE contact lens (Ultravision Pty, Ltd, Brisbane, Australia). Best spectacle-corrected visual acuity (BSCVA), uncorrected (Ultravision Pty, Ltd, Brisbane, Australia) visual acuity (UCVA), subjective cycloplegic refraction, biomicroscopy, corneal topography, optical pachymetry, and aberrometry were performed at baseline and one and eight nights orthokeratology. The short-term effect of orthokeratology using corneal topography, tomography, and ocular aberrations was evaluated.
  
  
  RESULTS
  The mean spherical equivalent changed from -2.24 +/- 0.98 diopters (D) at baseline to 0.15 +/- 0.76 D after the eight nights of lens wear (P = .001). All patients had an UCVA of 20/30, 69.2% with 20/20. Changes in central corneal pachymetry were not observed. There was a statistically significant increase in the temporal corneal thickness from night one, without any difference between nights one and eight (P > .001). A significant increase of higher-order root mean square values was observed from baseline (0.42 +/- 0.16 mum), night one (0.81 +/- 0.24 mum), and night eight (1.04 +/- 0.24 mum). Increases in coma (Z7+Z8) and spherical aberration (Z12) were observed. Positive horizontal (Z8) coma increased in right eyes, and negative horizontal (Z8) coma increased in left eyes (P < .001).
  
  
  CONCLUSIONS
  Myopia reduction resulting from rapid central corneal flattening and improvement of UCVA occurred after orthokeratology. Higher-order aberrations (HOAs), particularly spherical aberration and coma, increased significantly during the orthokeratology test. An increase of temporal pachymetry and differences in coma direction induced between the eyes may be related to the subclinical lens decentration temporally.
authors.affiliation: Contact Lens & Refractive Surgery Sectors, Department of Ophthalmology, Federal University of São Paulo/Paulista School of Medicine UNIFESP/EPM, São Paulo, Brazil. ianestillitano@oftalmol.epm.br
authors.forename: Iane Gonçalves
authors.initials: IG
authors.lastname: Stillitano
authors.forename: Maria Regina
authors.initials: MR
authors.lastname: Chalita
authors.forename: Paulo
authors.initials: P
authors.lastname: Schor
authors.forename: Eduardo
authors.initials: E
authors.lastname: Maidana
authors.forename: Marcelo Mastromonico
authors.initials: MM
authors.lastname: Lui
authors.forename: Cesar
authors.initials: C
authors.lastname: Lipener
authors.forename: Ana Luisa
authors.initials: AL
authors.lastname: Hofling-Lima
mesh_terms: D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D003261:Contact Lenses; D003315:Cornea / Q000000981:diagnostic imaging / Q000503:physiopathology*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology* / Q000628:therapy*; D011446:Prospective Studies; D017755:Prosthesis Fitting; D012029:Refraction, Ocular / Q000502:physiology; D014463:Ultrasonography; D014792:Visual Acuity / Q000502:physiology