May 2007
Volume 48, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2007
Ora Measurements After PRK and LASIK
N. Gupta; K. L. Fry; P. S. Hersh
Author Affiliations & Notes
  • N. Gupta
    Cornea and Laser Eye Institute, Teaneck, New Jersey
  • K. L. Fry
    Cornea and Laser Eye Institute, Teaneck, New Jersey
  • P. S. Hersh
    The Institute of Ophthalmology and Visual Science, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey
  • Footnotes
    Commercial Relationships N. Gupta, None; K.L. Fry, None; P.S. Hersh, None.
  • Footnotes
    Support None.
Investigative Ophthalmology & Visual Science May 2007, Vol.48, 5331. doi:
  • Views
  • Share
  • Tools
    • Alerts
      User Alerts
      You are adding an alert for:
      Ora Measurements After PRK and LASIK
      You will receive an email whenever this article is corrected, updated, or cited in the literature. You can manage this and all other alerts in My Account
      The alert will be sent to:
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation
      Citation

      N. Gupta, K. L. Fry, P. S. Hersh; Ora Measurements After PRK and LASIK. Invest. Ophthalmol. Vis. Sci. 2007;48(13):5331.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

      ×
    • Get Permissions
  • Supplements
Abstract

Purpose:: To analyze corneal biomechanics following LASIK and PRK.

Methods:: A retrospective chart review was carried out on 113 eyes that underwent LASIK and 121 eyes that underwent PRK for the treatment of myopia or myopia with astigmatism. Pre- and postoperative data at three months following surgery was assessed including: UCVA, BSCVA, MRSE, and predictability. The Ocular Response Analyzer (Reichert Inc.) was used to gather biomechanical data, including corneal hysteresis (CH) and corneal resistance factor (CRF).

Results:: Mean preoperative MRSE for LASIK and PRK eyes was -4.34D (ranging -0.68 to -8.35) and -6.64D (ranging -0.58 to -13.15) respectively. Three months postoperatively, mean predictability was 0.00D (SD 0.58) for LASIK eyes and -0.21D (SD 0.81) for PRK eyes.Mean CH showed a statistically significant decrease following LASIK and PRK in all eyes (p<0.01). Mean CH decreased from 10.77mmHg (SD 1.50) to 8.92mmHg (SD 1.21) for LASIK eyes and from 10.41mmHG (SD 1.95) to 7.56mmHg (SD 1.48) for PRK eyes. Mean CRF also showed a statistically significant decrease after surgery (p<0.01 for LASIK and PRK eyes). Mean CRF decreased from 10.5mmHG (SD 1.82) to 7.3mmHg (SD 1.48) for LASIK eyes and from 10.09mmHg (SD 2.09) to 6.1mmHg (SD 1.88) for PRK eyes. Comparison of mean change in CH showed that PRK induced a statistically significant greater change in CH compared to LASIK eyes (p<0.01). Mean change in CH for LASIK eyes was 17.8% compared to 26.5% for PRK eyes. Comparison of change in CRF for LASIK and PRK was 30.5% and 39.8% respectively which failed to reach significance. No association between preoperative CH or CRF and predictability was found.

Conclusions:: Refractive surgery induces significant changes in the biomechanical properties of the cornea with a decrease in CH and CRF values. The clinical implications, if any, remain to be clarified.

Keywords: refractive surgery • clinical (human) or epidemiologic studies: outcomes/complications • clinical (human) or epidemiologic studies: systems/equipment/techniques 
© 2007, The Association for Research in Vision and Ophthalmology, Inc., all rights reserved. Permission to republish any abstract or part of an abstract in any form must be obtained in writing from the ARVO Office prior to publication.
Copyright © 2024 Association for Research in Vision and Ophthalmology.
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×
This site uses cookies. By continuing to use our website, you are agreeing to our privacy policy.Accept