Research Papers: Therapeutic

Asphericity analysis using corneal wavefront and topographic meridional fits

[+] Author Affiliations
Samuel Arba-Mosquera

University of Valladolid, Instituto de Oftalmobiología Aplicada, Refractive Surgery and Quality of Vision, Valladolid, E-47004 Spain andSCHWIND eye-tech-solutions, Research and Development, Mainparkstrasse 6-10, Kleinostheim, D-63801 Germany

Jesús Merayo-Lloves

University of Valladolid, Instituto de Oftalmobiología Aplicada, Refractive Surgery and Quality of Vision, Valladolid, E-47004 Spain

Diego de Ortueta

Augenzentrum Recklinghausen, Recklinghausen, Germany

J. Biomed. Opt. 15(2), 028003 (April 12, 2010). doi:10.1117/1.3382910
History: Received October 19, 2009; Revised February 11, 2010; Accepted February 22, 2010; Published April 12, 2010; Online April 12, 2010
Text Size: A A A

The calculation of corneal asphericity as a 3-D fit renders more accurate results when it is based on the corneal wavefront aberrations rather than on the corneal topography of the principal meridians. A more accurate prediction could be obtained for hyperopic treatments compared to myopic treatments. We evaluate a method to calculate corneal asphericity and asphericity changes after refractive surgery. Sixty eyes of 15 consecutive myopic patients and 15 consecutive hyperopic patients (n=30 each) are retrospectively evaluated. Preoperative and 3-month-postoperative topographic and corneal wavefront analyses are performed using corneal topography. Ablations are performed using a laser with an aberration-free profile. Topographic changes in asphericity and corneal aberrations are evaluated for a 6-mm corneal diameter. The induction of corneal spherical aberrations and asphericity changes correlates with the achieved defocus correction. Preoperatively as well as post-operatively, asphericity calculated from the topography meridians correlates with asphericity calculated from the corneal wavefront in myopic and hyperopic treatments. A stronger correlation between postoperative asphericity and the ideally expected/predicted asphericity is obtained based on aberration-free assumptions calculated from corneal wavefront values rather than from the meridians. In hyperopic treatments, a better correlation can be obtained compared to the correlation in myopic treatments. Corneal asphericity calculated from corneal wavefront aberrations represents a 3-D fit of the corneal surface; asphericity calculated from the main topographic meridians represents a 2-D fit of the principal corneal meridians. Postoperative corneal asphericity can be calculated from corneal wavefront aberrations with higher fidelity than from corneal topography of the principal meridians. Hyperopic treatments show a greater accuracy than myopic treatments.

Figures in this Article
© 2010 Society of Photo-Optical Instrumentation Engineers

Citation

Samuel Arba-Mosquera ; Jesús Merayo-Lloves and Diego de Ortueta
"Asphericity analysis using corneal wavefront and topographic meridional fits", J. Biomed. Opt. 15(2), 028003 (April 12, 2010). ; http://dx.doi.org/10.1117/1.3382910


Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Topic Collections

PubMed Articles
Advertisement
  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.