Corneal changes and wavefront analysis after orthokeratology fitting test.
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.
Stillitano
Iane Gonçalves
IG
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
Chalita
Maria Regina
MR
Schor
Paulo
P
Maidana
Eduardo
E
Lui
Marcelo Mastromonico
MM
Lipener
Cesar
C
Hofling-Lima
Ana Luisa
AL
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