Corneal stromal depth of the demarcation line in ‘accelerated corneal cross-linking’ with different concentrations of riboflavin solutions

  • Dilay Ozek
  • Ozlem Evren Kemer
  • Pinar Altiaylik Ozer
Original Paper



The aim of this study is to compare the effect of different riboflavin solutions (hypotonic and isotonic) used during accelerated corneal cross-linking (CXL) on the mean depth of the demarcation line (DDL) formed in corneal stroma.


This prospective, cross-sectional study included 38 eyes of 26 patients. All patients underwent accelerated CXL due to progressive keratoconus. When the corneal epithelium was removed, 17 eyes of 12 patients with corneal thickness < 400 µm were categorized as Group 1, and 21 eyes of 14 patients with corneal thickness > 400 µm as Group 2. Hypotonic riboflavin was applied to Group 1 patients, and isotonic riboflavin to Group 2 patients. Anterior segment optical coherence tomography was performed on all patients by two independent observers at the end of the first and third months.


Group 1 included 5 male and 7 female patients with an average age of 25.1 ± 8.0 years, whereas Group 2 included 7 male and 7 female patients with an average age of 31.8 ± 10.12 years. At the end of the first month, the mean DDL in Group 1 and Group 2 was 180.32 ± 10.26 and 287.21 ± 15.01 µm, respectively. This difference was statistically significant (p < 0.05).


Application of different riboflavin solutions was observed to have an effect on measured corneal thickness after saturation and the depth of the demarcation line. The use of hypotonic riboflavin results in swelling of the cornea and more superficial localization of the stromal demarcation line after CXL.


Keratoconus Accelerated corneal cross-linking Riboflavin Demarcation line 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical standards

The study was conducted in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.

Informed consent

It was obtained from all individual participants included in the study.


  1. 1.
    Ziaei M, Barsam A, Shamie N et al (2015) Cornea clinical committee reshaping procedures for the surgical management of corneal ectasia. J Cataract Refract Surg 41:842–872CrossRefPubMedGoogle Scholar
  2. 2.
    Seiler T, Hafezi F (2006) Corneal cross-linking-induced stromal demarcation line. Cornea 25:1057–1059CrossRefPubMedGoogle Scholar
  3. 3.
    Dupps WJ Jr, Netto MV, Herekar S, Krueger RR (2007) Surface wave elastometry of the cornea in porcine and human donor eyes. J Cataract Refract Surg 23:66–75Google Scholar
  4. 4.
    Spoerl E, Wollensak G, Seiler T (2004) Increased resistance of crosslinked cornea against enzymatic digestion. Curr Eye Res 29:35–40CrossRefPubMedGoogle Scholar
  5. 5.
    Park J, Gritz DC (2013) Evolution in the use of intrastromal corneal ring segments for corneal ectasia. Curr Opin Ophthalmol 24:296–301CrossRefPubMedGoogle Scholar
  6. 6.
    Wollensak G, Spoerl E, Seiler T (2003) Riboflavin/ultraviolet-A-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 135:620–627CrossRefPubMedGoogle Scholar
  7. 7.
    Wollensak G, Spoerl E, Reber F, Seiler T (2004) Keratocyte cytotoxicity of riboflavin/UVA treatment in vitro. Eye 18:718–722CrossRefPubMedGoogle Scholar
  8. 8.
    Wollensak G, Spoerl E, Wilsch M, Seiler T (2003) Endothelial cell damage after riboflavin-ultraviolet: a treatment in the rabbit. J Cataract Refract Surg 29:1786–1790CrossRefPubMedGoogle Scholar
  9. 9.
    Maurice DM, Giardini AA (1951) Swelling of the cornea in vivo after the destruction of its limiting layers. Br J Ophthalmol 35:791–797CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Schmidinger G, Pachala M, Prager F (2013) Pachymetry changes during corneal crosslinking: effect of closed eyelids and hypotonic riboflavin solution. J Cataract Refract Surg 39:1179–1183CrossRefPubMedGoogle Scholar
  11. 11.
    Hafezi F, Mrochen M, Iseli HP, Seiler T (2009) Collagen crosslinking with ultraviolet-A and hypoosmolar riboflavin solution in thin corneas. J Cataract Refract Surg 35:621–624CrossRefPubMedGoogle Scholar
  12. 12.
    Raiskup F, Spoerl E (2011) Corneal cross-linking with hypo-osmolar riboflavin solution in thin keratoconic corneas. Am J Ophthalmol 152:28–32CrossRefPubMedGoogle Scholar
  13. 13.
    Ozgurhan EB, Sezgin Akcay BI, Yildirim Y, Karatas G, Kurt T, Demirok A (2014) Evaluation of corneal stromal demarcation line after two different protocols of accelerated corneal collagen cross-linking procedures using anterior segment optical coherence tomography and confocal microscopy. J Ophthalmol 2014:981893CrossRefPubMedPubMedCentralGoogle Scholar
  14. 14.
    Raiskup F, Spoerl E (2013) Corneal crosslinking with riboflavin and ultraviolet A. I. Principles. Ocul Surf 11:65–74CrossRefPubMedGoogle Scholar
  15. 15.
    Richoz O, Hammer A, Tabibian D, Gatzioufas Z, Hafezi F (2013) The biomechanical effect of corneal collagen cross-linking (CXL) with riboflavin and UV-A is oxygen dependent. Transl Vis Sci Technol 2:6–8CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    Kymionis GD, Tsoulnaras KI, Grentzelos MA et al (2014) Corneal stroma demarcation line after standard and high-intensity collagen crosslinking determined with anterior segment optical coherence tomography. J Cataract Refract Surg 40:736–740CrossRefPubMedGoogle Scholar
  17. 17.
    Yam JC, Chan CW, Cheng AC (2012) Corneal collagen cross-linking demarcation line depth assessed by Visante OCT after CXL for keratoconus and corneal ectasia. J Refract Surg 28:475–481CrossRefPubMedGoogle Scholar
  18. 18.
    Moramarco A, Iovieno A, Sartori A, Fontana L (2015) Corneal stromal demarcation line after accelerated crosslinking using continuous and pulsed light. J Cataract Refract Surg 41:2546–2551CrossRefPubMedGoogle Scholar
  19. 19.
    Doors M, Tahzib NG, Eggink FA, Berendschot TT, Webers CA, Nuijts RM (2009) Use of anterior segment optical coherence tomography to study corneal changes after collagen cross-linking. Am J Ophthalmol 148:844–851CrossRefPubMedGoogle Scholar
  20. 20.
    Gatzioufas Z, Balidis M, Kozeis N (2016) Is the corneal stromal demarcation line depth a true indicator of corneal collagen crosslinking efficacy. J Cataract Refract Surg 42:804CrossRefPubMedGoogle Scholar
  21. 21.
    Tomita M, Mita M, Huseynova T (2014) Accelerated versus conventional corneal collagen crosslinking. J Cataract Refract Surg 40:1013–1020CrossRefPubMedGoogle Scholar
  22. 22.
    Wernli J, Schumacher S, Spoerl E, Mrochen M (2013) The efficacy of corneal cross-linking shows a sudden decrease with very high intensity UV light and short treatment time. Invest Ophthalmol Vis Sci 54:1176–1180CrossRefPubMedGoogle Scholar
  23. 23.
    Doors M, Tahzib NG, Eggink FA, Berendschot TTJM, Webers CAB, Nuijts RMMA (2009) Use of anterior segment optical coherence tomography to study corneal changes after collagen cross-linking. Am J Ophthalmol 148:844–851CrossRefPubMedGoogle Scholar
  24. 24.
    Mazzotta C, Traversi C, Paradiso AL, Latronico ME, Rechichi M (2014) Pulsed light accelerated crosslinking versus continuous light accelerated crosslinking: one-year results. J Ophthalmol 2014:604731CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer Nature B.V. 2018

Authors and Affiliations

  1. 1.Department of OphthalmologyAnkara Numune Education and Research HospitalAnkaraTurkey
  2. 2.Department of Ophthalmology, Faculty of MedicineUfuk UniversityAnkaraTurkey
  3. 3.AnkaraTurkey

Personalised recommendations