J Korean Ophthalmol Soc.  2012 Nov;53(11):1591-1596.

Changes in Corneal Keratometry Readings after Corneal Collagen Cross-Linking Using Alcohol in Keratoconus Patients

  • 1The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea. seoky@yuhs.ac
  • 2Siloam Eye Hospital, Seoul, Korea.


To evaluate the changes in corneal keratometry (K) readings after corneal collagen cross- linking (CXL) using 20% alcohol in primary keratoconus and keratectasia after refractive surgery.
Twelve eyes of 10 patients with primary keratoconus and 3 eyes of 3 patients with keratectasia after refractive surgery were included in the present study. Best-corrected visual acuity (BCVA) and mean K, corneal astigmatism by corneal topography, and mean K, corneal astigmatism, and spherical equivalent (SE) by auto refractometer were evaluated at baseline, and 6 months postoperatively. Eight eyes of 7 patients were also evaluated 1 year postoperatively.
Mean BCVA improved from log MAR 0.66 +/- 0.50 to log MAR 0.55 +/- 0.58 (p = 0.100) at 6 month after CXL. In corneal topography, mean K significantly decreased from 50.04 +/- 5.88 D to 49.18 +/- 6.15 D (p = 0.019), and corneal astigmatism slightly decreased from 5.33 +/- 4.47 D to 5.29 +/- 4.88 D (p = 0.755) at 6 months after CXL. According to the auto refractometer, mean K significantly decreased from 48.53 +/- 5.94 D to 47.95 +/- 5.79 D (p = 0.038), corneal astigmatism significantly decreased from 3.95 +/- 2.54 D to 3.52 +/- 2.40 D (p = 0.010), and SE significantly decreased from -6.25 +/- 3.45 D to -5.40 +/- 2.91 D (p = 0.037) at 6 months after CXL. Significant mean K and corneal astigmatism decreases in topography were also observed at 1 year after CXL. Complications related to CXL were not observed.
CXL using 20% alcohol appears to be a safe and promising treatment modality with less corneal stromal damage in progressive primary keratoconus and keratectasia after refractive surgery.


Corneal collagen cross-linking; Keratectasia; Keratoconus; Keratometry

MeSH Terms

Corneal Topography
Refractive Surgical Procedures
Visual Acuity


1. Rabinowitz YS. Keratoconus. Surv Ophthalmol. 1998. 42:297–319.
2. Lembach RG. Use of contact lenses for management of keratoconus. Ophthalmol Clin North Am. 2003. 16:383–394.
3. Teng CC. Electron microscope study of the pathology of keratoconus: I. Am J Ophthalmol. 1963. 55:18–47.
4. Espandar L, Meyer J. Keratoconus: overview and update on treatment. Middle East Afr J Ophthalmol. 2010. 17:15–20.
5. Rabinowitz YS, Garbus J, McDonnell PJ. Computer-assisted corneal topography in family members of patients with keratoconus. Arch Ophthalmol. 1990. 108:365–371.
6. Colin J, Velou S. Current surgical options for keratoconus. J Cataract Refract Surg. 2003. 29:379–386.
7. Hoyer A, Raiskup-Wolf F, Spörl E, Pillunat LE. [Collagen cross-linking with riboflavin and UVA light in keratoconus. Results from Dresden]. Ophthalmologe. 2009. 106:133–140.
8. Caporossi A, Mazzotta C, Baiocchi S, Caporossi T. Long-term results of riboflavin ultraviolet a corneal collagen cross-linking for keratoconus in Italy: the Siena eye cross study. Am J Ophthalmol. 2010. 149:585–593.
9. Lee P, Jin KH. Clinical results of riboflavin and ultraviolet-A-induced corneal cross-linking for progressive keratoconus in Korean patients. J Korean Ophthalmol Soc. 2011. 52:23–28.
10. al-Abdulla NA, Jabbur NS, O'Brien TP. Astigmatism outcomes following spherical photorefractive keratectomy for myopia. J Refract Surg. 1998. 14:610–614.
11. Wilson SE, He YG, Weng J, et al. Epithelial injury induces keratocyte apoptosis: hypothesized role for the interleukin-1 system in the modulation of corneal tissue organization and wound healing. Exp Eye Res. 1996. 62:325–327.
12. Lee HK, Lee KS, Kim JK, et al. Epithelial healing and clinical outcomes in excimer laser photorefractive surgery following three epithelial removal techniques: mechanical, alcohol, and excimer laser. Am J Ophthalmol. 2005. 139:56–63.
13. Wittig-Silva C, Whiting M, Lamoureux E, et al. A randomized controlled trial of corneal collagen cross-linking in progressive keratoconus: preliminary results. J Refract Surg. 2008. 24:S720–S725.
14. Sung HW, Chang WH, Ma CY, Lee MH. Crosslinking of biological tissues using genipin and/or carbodiimide. J Biomed Mater Res A. 2003. 64:427–438.
15. Robins SP. Biochemistry and functional significance of collagen cross-linking. Biochem Soc Trans. 2007. 35(Pt 5):849–852.
16. Tuft SJ, Moodaley LC, Gregory WM, et al. Prognostic factors for the progression of keratoconus. Ophthalmology. 1994. 101:439–447.
17. Seiler T, Huhle S, Spoerl E, Kunath H. Manifest diabetes and keratoconus: a retrospective case-control study. Graefes Arch Clin Exp Ophthalmol. 2000. 238:822–825.
18. Cannon DJ, Foster CS. Collagen crosslinking in keratoconus. Invest Ophthalmol Vis Sci. 1978. 17:63–65.
19. Spoerl E, Huhle M, Seiler T. Induction of cross-links in corneal tissue. Exp Eye Res. 1998. 66:97–103.
20. Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003. 135:620–627.
21. Wollensak G. Crosslinking treatment of progressive keratoconus: new hope. Curr Opin Ophthalmol. 2006. 17:356–360.
22. Wollensak G, Spoerl E, Wilsch M, Seiler T. Endothelial cell damage after riboflavin-ultraviolet-A-treatment in the rabbit. J Cataract Refract Surg. 2003. 29:1786–1790.
23. Samaras KE, Lake DB. Corneal collagen cross linking(CXL): a review. Int Ophthalmol Clin. 2010. 50:89–100.
24. Spörl E, Huhle M, Kasper M, Seiler T. [Increased rigidity of the cornea caused by intrastromal cross-linking]. Ophthalmologe. 1997. 94:902–906.
25. Wollensak G, Spoerl E, Seiler T. Stress-strain measurements of human and porcine corneas after riboflavin-ultraviolet-A-induced cross-linking. J Cataract Refract Surg. 2003. 29:1780–1785.
26. Kohlhaas M, Spoerl E, Schilde T, et al. Biomechanical evidence of the distribution of cross-links in corneas treated with riboflavin and ultraviolet A light. J Cataract Refract Surg. 2006. 32:279–283.
27. Agrawal VB. Corneal collagen cross-linking with riboflavin and ultraviolet - a light for keratoconus: results in Indian eyes. Indian J Ophthalmol. 2009. 57:111–114.
28. Einollahi B, Baradaran-Rafii A, Rezaei-Kanavi M, et al. Mechanical versus alcohol-assisted epithelial debridement during photorefractive keratectomy: a confocal microscopic clinical trial. J Refract Surg. 2011. 27:887–893.
29. Paik DC, Wen Q, Braunstein RE, et al. Initial studies using aliphatic beta-nitro alcohols for therapeutic corneal cross-linking. Invest Ophthalmol Vis Sci. 2009. 50:1098–1105.
30. Koppen C, Vryghem JC, Gobin L, Tassignon MJ. Keratitis and corneal scarring after UVA/riboflavin cross-linking for keratoconus. J Refract Surg. 2009. 25:S819–S823.
31. Kymionis GD, Bouzoukis DI, Diakonis VF, et al. Diffuse lamellar keratitis after corneal crosslinking in a patient with post-laser in situ keratomileusis corneal ectasia. J Cataract Refract Surg. 2007. 33:2135–2137.
32. Kymionis GD, Portaliou DM, Bouzoukis DI, et al. Herpetic keratitis with iritis after corneal crosslinking with riboflavin and ultraviolet A for keratoconus. J Cataract Refract Surg. 2007. 33:1982–1984.
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