International Journal of Keratoconus and Ectatic Corneal Diseases

Register      Login

VOLUME 6 , ISSUE 2 ( July-December, 2017 ) > List of Articles

RESEARCH ARTICLE

Reduced High-order Aberrations using Wavefront-guided Partial Photorefractive Keratectomy and Accelerated Epithelium-off Corneal Cross-linking for Keratoconus

Guillermo Rocha, Victor Penner, Kylee Lewis

Citation Information : Rocha G, Penner V, Lewis K. Reduced High-order Aberrations using Wavefront-guided Partial Photorefractive Keratectomy and Accelerated Epithelium-off Corneal Cross-linking for Keratoconus. Int J Kerat Ect Cor Dis 2017; 6 (2):73-77.

DOI: 10.5005/jp-journals-10025-1146

License: CC BY 3.0

Published Online: 00-12-2017

Copyright Statement:  Copyright © 2017; Jaypee Brothers Medical Publishers (P) Ltd.


Abstract

Purpose

To demonstrate clinical outcomes of epithelium-off corneal cross-linking (CXL) in combination with wavefront-guided photorefractive keratectomy (PRK) for the treatment of keratoconuns.

Materials and methods

Total, 28 keratoconic eyes of 21 patients were included. The Sirius Wavefront Analyzer (SCHWIND eye-tech-solutions GmbH and Co. KG) was used to evaluate the high-order aberrations (HOAs). The coupled Amaris 750S excimer laser then performed a PRK of no more than 40 μm using the measured HOA. The CXL was then carried out respecting the standard of 400 μm of corneal thickness.

Results

The average age was 32 (15—48) years. Uncorrected distance visual acuity (UDVA) improved from 0.58 to 0.31 logMAR (p < 0.001), with best corrected distance visual acuity (CDVA) improving from 0.03 to 0.02 logMAR (p = 0.7).

On manifest refraction, the average spherical component decreased from –1.87 to –1.40 D (0.47 ± 2.12, p = 0.4). Cylinder decreased from 2.18 to 0.87 D (1.31 ± 1.14 D, p < 0.001).

All HOAs decreased: total HO 0.94 to 0.58 (0.36 ± 0.42, p = 0.05); spherical aberration: 0.142 to –0.018 (0.160 ± 0.160, p < 0.001); secondary astigmatism: 0.21 to 0.11 (0.10 ± 0.11, p = 0.02); coma: 0.80 to 0.42 (0.38 ± 0.47, p = 0.03); trefoil: 0.33 to 0.29 (0.04 ± 0.17, p = 0.7).

Conclusion

Utilizing HOA to guide the laser treatment in combination with CXL resulted in a significant decrease of HOA at 6 months postprocedure. This is a small case series, but demonstrates a promising trend of improved HOA. Considering that keratoconic eyes have very irregular surfaces with significant HOA, reducing these aberrations should improve best corrected quality of vision. Having longer follow-up and greater numbers may demonstrate a clearer improvement.

How to cite this article

Penner V, Lewis K, Rocha G. Reduced High-order Aberrations using Wavefront-guided Partial Photorefractive Keratectomy and Accelerated Epithelium-off Corneal Cross-linking for Keratoconus. Int J Kerat Ect Cor Dis 2017;6(2):73-77.


PDF Share
  1. , Guell JL, Malecaze F, Nishida K, Sangwan VS; Group of Panelists for the Global Delphi Panel of Keratoconus and Ectatic Diseases. Global consensus on keratoconus and ectatic diseases. Cornea 2015 Apr;34(4):359-369.
  2. Reshaping procedures for the surgical management of corneal ectasia. J Cataract Refract Surg 2015 Apr;41(4):842-872.
  3. Correcting keratoconus with intracorneal rings. J Cataract Refract Surg 2000 Aug;26(8):1117-1122.
  4. Intracorneal rings for keratoconus and keratectasia. J Cataract Refract Surg 2007 Jul;33(7):1303-1314.
  5. Intrastromal corneal ring segment implantation in 219 keratoconic eyes at different stages. Graefes Arch Clin Exp Ophthalmol 2011 Nov;249(11):1705-1712.
  6. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 2003 May;135(5):620-627.
  7. Collagen cross-linking (CCL) with sequential topography-guided PRK: a temporizing alternative for keratoconus to penetrating keratoplasty. Cornea 2007 Aug;26(7):891-895.
  8. Topography-guided transepithelial surface ablation followed by corneal collagen cross-linking performed in a single combined procedure for the treatment of keratoconus and pellucid marginal degeneration. J Refract Surg 2010 Feb;26(2):145-152.
  9. Simultaneous topography-guided PRK followed by corneal collagen cross-linking for keratoconus. J Refract Surg 2009 Sep;25(9):S807-S811.
  10. Transepithelial photorefractive keratectomy with crosslinking for keratoconus. Open Ophthalmol J 2013 Oct;7:63-68.
  11. Keratoconus management: long-term stability of topography-guided normalization combined with high-fluence CXL stabilization (the Athens Protocol). J Refract Surg 2014 Feb;30(2):88-93.
  12. Photorefractive keratectomy followed by cross-linking versus cross-linking alone for management of progressive keratoconus: two-year follow-up. Am J Ophthalmol 2013 Jan;155(1):54.e1-65.e1.
  13. Use of adaptive optics to determine the optimal ocular spherical aberration. J Cataract Refract Surg 2007 Oct;33(10):1721-1726.
  14. Visual benefit of correcting higher order aberrations of the eye. J Refract Surg 2000 Sep-Oct;16(5):S554-S559.
  15. Higher-order aberrations 1 year after corneal collagen crosslinking for keratoconus and their independent effect on visual acuity. J Cataract Refract Surg 2016 Jul;42(7):1046-1052.
  16. Laser vision correction with Q factor modification for keratoconus management. Curr Eye Res 2017 Apr;42(4):542-548.
  17. Wavefront-guided laser treatment using a high-resolution aberrometer to measure irregular corneas: a pilot study. J Refract Surg 2015 Jun;31(6):411-418.
  18. Cone location-dependent outcomes after combined topography-guided photorefractive keratectomy and collagen cross-linking. Am J Ophthalmol 2015 Mar;159(3):419.e2-425.e2.
  19. Pentacam posterior and anterior corneal aberrations in normal and keratoconic eyes. Clin Exp Optom 2009 May;92(3):297-303.
  20. Topography-guided surface ablation for forme fruste keratoconus. Ophthalmology 2006 Dec;113(12):2198-2202.
  21. Simultaneous topography-guided photorefractive keratectomy followed by corneal collagen cross-linking for keratoconus. Am J Ophthalmol 2011 Nov;152(5):748-755.
  22. Corneal higher order aberrations: a method to grade keratoconus. J Refract Surg 2006 Jun;22(6):539-545.
  23. Wave front-guided photorefractive keratectomy using a high-resolution aberrometer after corneal collagen cross-linking in keratoconus. Cornea 2016 Jul;35(7):946-953.
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.