[Optical performance of different soft contact lenses based on wavefront analysis].
OBJECTIVE
To evaluate the visual performance by wavefront analyses of six different kinds of soft contact lenses: Cooperflex (Cooper Vision), Frequency(R) 55 Aspheric (Cooper Vision), World Vision FW (World Vision), Pure Vision (Bausch & Lomb), Focus Monthly (Ciba Vision) and Focus Choice AB (Ciba Vision).


METHODS
A prospective study was performed with 130 eyes of 71 myopic or hyperopic patients with astigmatism until 1.50 diopter and best corrected visual acuity 20/20 or better. The patients first underwent ophthalmic examination and then wavefront analyses without visual correction and wearing one of the different contact lenses included in the study. The patients were divided into six similar groups, each one tested with one of the six lenses included in the study.


RESULTS
Changes at the values of high order aberrations were verified during the use of contact lenses. In 78 (60%) of the 130 analyzed eyes an increase at the RMS (rooth mean square) values during the use of contact lens was detected. All types of analyzed contact lenses showed an increase of 'coma' aberrations due to contact lens use. Frequency Aspheric and Cooperflex had the best visual performance in relation to 'coma'. There was a decrease in the medium value of spherical aberrations during the use of contact lenses, higher in myopic patients than in the hyperopic. There was an increase in the other high order aberrations (that exclude the third order 'coma' and fourth order spherical aberration) characterized by the component 'others' on the aberrometry examination. Focus Choice AB had the best visual performance of this component.


CONCLUSIONS
The use of soft contact lenses modifies the performance of high order aberrations, showing an increase of the medium values of asymmetric Zernike aberrations. This was not observed for symmetric spherical aberrations. No statistically significant differences were observed between the performance of six kinds of lenses included at this study.
Gatti
Roberta Fagnani
RF
Setor de Refração e Lente de Contato, Universidade Federal de São Paulo, São Paulo, SP, Brasil. r.gatti@terra.com.br
Lipener
César
C
D000328:Adult; D000704:Analysis of Variance; D003263:Contact Lenses, Hydrophilic / Q000145:classification*; D019781:Corneal Topography / Q000379:methods; D006801:Humans; D011446:Prospective Studies; D012016:Reference Values; D012029:Refraction, Ocular / Q000502:physiology*; D012030:Refractive Errors / Q000503:physiopathology* / Q000534:rehabilitation