Original Article 

Intraocular Straylight and Contrast Sensitivity After Contralateral Wavefront-Guided LASIK and Wavefront-Guided PRK for Myopia

Jackson Barreto Jr., MD; Mirella T.S. Barboni, MSc; Claudia Feitosa-Santana, PhD; João R. Sato, MSc; Samir J. Bechara, MD; Dora F. Ventura, PhD; Milton Ruiz Alves, MD

Abstract

Purpose:

To compare intraocular straylight measurements and contrast sensitivity after wavefront-guided LASIK (WFG LASIK) in one eye and wavefront-guided photorefractive keratectomy (WFG PRK) in the fellow eye for myopia and myopic astigmatism correction.

Methods:

A prospective, randomized study of 22 eyes of 11 patients who underwent simultaneous WFG LASIK and WFG PRK (contralateral eye). Both groups were treated with the NIDEK Advanced Vision Excimer Laser System, and a microkeratome was used for flap creation in the WFG LASIK group. High and low contrast visual acuity, wavefront analysis, contrast sensitivity, and retinal straylight measurements were performed preoperatively and at 3, 6, and 12 months postoperatively. A third-generation straylight meter, C-Quant (Oculus Optikgeräte GmbH), was used for measuring intraocular straylight.

Results:

Twelve months postoperatively, mean uncorrected distance visual acuity was −0.06±0.07 logMAR in the WFG LASIK group and −0.10±0.10 logMAR in the WFG PRK group. Mean preoperative intraocular straylight was 0.94±0.12 log s for the WFG LASIK group and 0.96±0.11 log s for the WFG PRK group. After 12 months, the mean straylight value was 1.01±0.1 log s for the WFG LASIK group and 0.97±0.12 log s for the WFG PRK group. No difference was found between techniques after 12 months (P=.306). No significant difference in photopic and mesopic contrast sensitivity between groups was noted.

Conclusions:

Intraocular straylight showed no statistically significant increase 1 year after WFG LASIK and WFG PRK. Higher order aberrations increased significantly after surgery for both groups. Nevertheless, WFG LASIK and WFG PRK yielded excellent visual acuity and contrast sensitivity performance without significant differences between techniques.

Authors

From the Refractive Surgery Service, Department of Ophthalmology (Barreto, Bechara, Alves), Neuroscience and Behavior (Barboni, Feitosa-Santana, Ventura), and Department of Experimental Psychology, Institute of Psychology (Barboni, Feitosa-Santana, Ventura), University of São Paulo, São Paulo, Brazil; Department of Psychology and Vision Sciences Laboratories & Institute of Mind and Biology (Feitosa-Santana), University of Chicago, Chicago, Illinois; and Center of Mathematics, Computational and Cognition (Sato), Federal University of ABC, Santo Andre, Brazil.

This study was supported by a postgraduate fellowship from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) to Dr Barreto and graduate fellowships from FAPESP to Drs Barboni and Feitosa-Santana (07/55125-1 and 05/53974-6, respectively), and a postdoctoral fellowship from NIH to Dr Feitosa-Santana (NIH EY-04802). Dr Ventura is a CNPq research fellow, and Dr Feitosa-Santana is an IMB (University of Chicago) research fellow. The remaining authors have no proprietary interest in the materials presented herein.

Correspondence: Jackson Barreto, Jr, MD, Rua Arruda Alvim, 136 ap 74, Pinheiros - CEP 05410-020, São Paulo - SP, Brazil. Fax: 99196869; E-mail: jackbj@terra.com.br

10.3928/1081597X-20090930-01

Purpose:

To compare intraocular straylight measurements and contrast sensitivity after wavefront-guided LASIK (WFG LASIK) in one eye and wavefront-guided photorefractive keratectomy (WFG PRK) in the fellow eye for myopia and myopic astigmatism correction.

Methods:

A prospective, randomized study of 22 eyes of 11 patients who underwent simultaneous WFG LASIK and WFG PRK (contralateral eye). Both groups were treated with the NIDEK Advanced Vision Excimer Laser System, and a microkeratome was used for flap creation in the WFG LASIK group. High and low contrast visual acuity, wavefront analysis, contrast sensitivity, and retinal straylight measurements were performed preoperatively and at 3, 6, and 12 months postoperatively. A third-generation straylight meter, C-Quant (Oculus Optikgeräte GmbH), was used for measuring intraocular straylight.

Results:

Twelve months postoperatively, mean uncorrected distance visual acuity was −0.06±0.07 logMAR in the WFG LASIK group and −0.10±0.10 logMAR in the WFG PRK group. Mean preoperative intraocular straylight was 0.94±0.12 log s for the WFG LASIK group and 0.96±0.11 log s for the WFG PRK group. After 12 months, the mean straylight value was 1.01±0.1 log s for the WFG LASIK group and 0.97±0.12 log s for the WFG PRK group. No difference was found between techniques after 12 months (P=.306). No significant difference in photopic and mesopic contrast sensitivity between groups was noted.

Conclusions:

Intraocular straylight showed no statistically significant increase 1 year after WFG LASIK and WFG PRK. Higher order aberrations increased significantly after surgery for both groups. Nevertheless, WFG LASIK and WFG PRK yielded excellent visual acuity and contrast sensitivity performance without significant differences between techniques.

From the Refractive Surgery Service, Department of Ophthalmology (Barreto, Bechara, Alves), Neuroscience and Behavior (Barboni, Feitosa-Santana, Ventura), and Department of Experimental Psychology, Institute of Psychology (Barboni, Feitosa-Santana, Ventura), University of São Paulo, São Paulo, Brazil; Department of Psychology and Vision Sciences Laboratories & Institute of Mind and Biology (Feitosa-Santana), University of Chicago, Chicago, Illinois; and Center of Mathematics, Computational and Cognition (Sato), Federal University of ABC, Santo Andre, Brazil.

This study was supported by a postgraduate fellowship from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) to Dr Barreto and graduate fellowships from FAPESP to Drs Barboni and Feitosa-Santana (07/55125-1 and 05/53974-6, respectively), and a postdoctoral fellowship from NIH to Dr Feitosa-Santana (NIH EY-04802). Dr Ventura is a CNPq research fellow, and Dr Feitosa-Santana is an IMB (University of Chicago) research fellow. The remaining authors have no proprietary interest in the materials presented herein.

Correspondence: Jackson Barreto, Jr, MD, Rua Arruda Alvim, 136 ap 74, Pinheiros - CEP 05410-020, São Paulo - SP, Brazil. Fax: 99196869; E-mail: jackbj@terra.com.br

  • ISRS Members:
Read This Article
  • Subscriber
  • Non-Subscriber
Read This Article
This Article
Advertisement
Advertisement