Collagen Cross Linking in Keratoconus: A Review
International Journal of Ophthalmology & Visual Science
Volume 1, Issue 1, November 2016, Pages: 20-24
Received: Oct. 31, 2016; Accepted: Nov. 29, 2016; Published: Jan. 3, 2017
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Bhavesh Makkar, Department of Ophthalmology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
Deepak Mishra, Department of Ophthalmology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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Corneal collagen cross-linking (CXL) is a therapeutic procedure that helps in increasing the corneal stiffness in the keratoconus eyes. It increases the collagen cross linking within the extracellular matrix (ECM). Ultraviolet-A (370 nm) irradiation of the cornea after saturation with the photosensitizer riboflavin is used. A minimum deepithelialized corneal thickness of 400 μm is recommended to avoid potential irradiation damage to the corneal endothelium but in advanced cases this is not achieved which limits the application of CXL in that category. Modifications have been done in the conventional CXL procedure to be applicable in thin corneas. The current review discusses different techniques employed to achieve this end and their results. The modifications in CXL halt the progression of keratectasia without postoperative complications. However, the evidence of safety and efficacy in the use of modified CXL protocols is still limited to few studies with few patients involved. Controlled studies with long-term follow-up are required to confirm the safety and efficacy of the modified protocols.
Keratoconus, Collagen Cross Linking, Thin Cornea
To cite this article
Bhavesh Makkar, Deepak Mishra, Collagen Cross Linking in Keratoconus: A Review, International Journal of Ophthalmology & Visual Science. Vol. 1, No. 1, 2016, pp. 20-24. doi: 10.11648/j.ijovs.20160101.13
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This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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