International Journal of Keratoconus and Ectatic Corneal Diseases

Register      Login

VOLUME 7 , ISSUE 1 ( 2018 ) > List of Articles


Technology of Local Cross-linking. Part 2: Experimental Results of Local Corneal Cross-linking

Sergey I Anisimov, Svetlana Y Anisimova, Anatoliy S Mistryukov, Natalia S Anisimova, Kirill A Zolotorevskiy, Ilia A Popov

Keywords : Accelerated, Cross-linking, Local, Meta-optics, Personalized.

Citation Information : Anisimov SI, Anisimova SY, Mistryukov AS, Anisimova NS, Zolotorevskiy KA, Popov IA. Technology of Local Cross-linking. Part 2: Experimental Results of Local Corneal Cross-linking. Int J Kerat Ect Cor Dis 2018; 7 (1):1-5.

DOI: 10.5005/jp-journals-10025-1152

License: CC BY-SA 3.0

Published Online: 01-06-2010

Copyright Statement:  Copyright © 2018; The Author(s).


Aim: The aim of the study was to assess the morphological changes in animal corneas following local cross-linking (CXL). Materials and methods: Experimental comparative study included nine isolated porcine eyeballs (ex vivo group) and nine Chinchilla rabbits, one eye per animal (in vivo group). All the corneas in both groups were saturated with 0.1% riboflavin and corneal CXL was performed with Locolink device (Transkontakt, Russia), a system that allows to deliver ultraviolet (UV) radiation through a mask of any pattern. One half of each cornea was cross-linked and the other half remained intact. Three corneas of each group were irradiated according to the standard Dresden protocol with 3.0 mW/cm2 for 30 minutes (5.4 J); yet, three corneas were irradiated in accelerated CXL mode I with 6.0 mW/cm2 for 15 minutes (5.4 J), and yet, three corneas were treated in accelerated CXL mode II with 5.0 mW/cm2 for 10 minutes (3.0 J). In the ex vivo group, the corneas of the whole isolated porcine eyeballs were examined with optical coherence tomography (OCT): The stromal demarcation line depth was evaluated by 10 different topographical points per image and the optical density of the corneal layers over the demarcation line was evaluated qualitatively as positive or negative. In the In vivo group, the rabbits were sacrificed 5 days after treatment, and their eyes were enucleated. Corneoscleral buttons were excised and subjected to histological and transmission electron microscopy (TEM) examination. Results: Ex vivo group: Ultrastructural examination and OCT imaging showed that the demarcation line was more superficial after accelerated CXL than after standard CXL. In vivo group. No histological change was detected in the intact area. The re-epithelialization was complete by 72 hours after the procedure. Ultrastructural and histological examination on day 5 following complete re-epithelialization of the cornea showed the presence of bridge-like chains forming cross-links between collagen fibrils in tangential sections. Keratocytes in irradiated zones were either in the state of apoptosis or were activated and produced newly formed collagen. Conclusion: The method of local CXL allows to accurately and selectively modify limited regions of the cornea leaving other areas intact. In the case of local irradiation of the cornea, UV structural changes occur only within the irradiated area. The optimal protocol for use in local CXL is the Dresden protocol.

PDF Share
  1. Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-ainduced collagen crosslinking for the treatment of keratoconus. Am J Ophtalmol 2003 May;135(5):620-627.
  2. Anisimov SI, Anisimova SY, Mistryukov AS. Personalized (local) UV crosslinking as a treatment of keratoconus and corneal ectasie. Ophtalmology 2017 Jan;15(3):195-199.
  3. Spoerl E, Mrochen M, Sliney D, Trokel S, Seiler T. Safety of UVA-riboflavin cross-linking of the cornea. Cornea 2007 May;26(4):385-389
  4. Sorkin N, Varssano D. Corneal collagen crosslinking: a systematic review. Issue 1. Ophthalmologica 2014 Apr;232(1):10-27.
  5. Raiskup F, Theuring A, Pillunat LE, Spoerl E. Corneal collagen crosslinking with riboflavin and ultraviolet–a light in progressive keratoconus: ten-year results. J Cataract Refract Surg 2015 Jan;41(1):41-46.
  6. Alnawaiseh M, Rosentreter A, Böhm MR, Eveslage M, Eter N, Zumhagen L. Accelerated (18 mW/cm2) corneal collagen cross-linking for progressive keratoconus. Cornea 2015 Nov;34(11):1427-1431.
  7. Elbaz U, Shen C, Lichtinger A, Zauberman NA, Goldich Y, Chan CC, Slomovic AR, Rootman DS. Accelerated (9-mW/ cm2) corneal collagen crosslinking for keratoconus–a 1-year follow-up. Cornea 2014 Aug;33(8):769-773.
  8. Cýnar Y, Cingü AK, Türkcü FM, Çýnar T, Yüksel H, Özkurt ZG, Çaça I. Comparison of accelerated and conventional corneal collagen cross-linking for progressive keratoconus. Cutan Ocul Toxicol 2014 Sep;33(3):218-222.
  9. Greenstein SA, Fry KL, Bhatt J, Hersh PS. Natural history of corneal haze after collagen crosslinking for keratoconus and corneal ectasia: Scheimpflug and biomicroscopic analysis. J Cataract Refract Surg 2010 Dec;36(12):2105-2014.
PDF Share
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.