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Current perspectives on corneal collagen crosslinking (CXL)

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Abstract

Corneal collagen crosslinking has revolutionized the treatment of keratoconus and post-refractive corneal ectasia in the past decade. Corneal crosslinking with riboflavin and ultraviolet A is proposed to halt the progression of keratectasia. In the original “Conventional Dresden Protocol” (C-CXL), the epithelium is removed prior to the crosslinking process to facilitate better absorption of riboflavin into the corneal stroma. Studies analyzing its short- and long-term outcomes revealed that although there are inconsistencies as to the effectiveness of this technique, the advantages prevail over the disadvantages. Therefore, corneal crosslinking (CXL) is widely used in current practice to treat keratoconus. In an attempt to improve the visual and topographical outcomes of C-CXL and to minimize time-related discomfort and endothelial-related side effects, various modifications such as accelerated crosslinking and transepithelial crosslinking methods have been introduced. The comparison of outcomes of these modified techniques with C-CXL has also returned contradictory results. Hence, it is difficult to clearly identify an optimal procedure that can overcome issues associated with the CXL. This review provides an up-to-date analysis on clinical and laboratory findings of these popular crosslinking protocols used in the treatment of keratoconus. It is evident from this review that in general, these modified techniques have succeeded in minimizing the immediate complications of the C-CXL technique. However, there were contradictory viewpoints regarding their effectiveness when compared with the conventional technique. Therefore, these modified techniques need to be further investigated to arrive at an optimal treatment option for keratoconus.

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Acknowledgements

The authors would like to acknowledge Mr. Robbie McPhee (illustrator/graphic artist at the Department of Anatomy, University of Otago) for assisting with the images.

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  1. Department of Anatomy, University of Otago, P.O. Box 913, 270 Great King Street, Dunedin, 9054, New Zealand

    Sandeepani K. Subasinghe & George J. Dias

  2. Ophthalmology Section, Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand

    Kelechi C. Ogbuehi

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  1. Sandeepani K. Subasinghe
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  2. Kelechi C. Ogbuehi
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Subasinghe, S.K., Ogbuehi, K.C. & Dias, G.J. Current perspectives on corneal collagen crosslinking (CXL). Graefes Arch Clin Exp Ophthalmol 256, 1363–1384 (2018). https://doi.org/10.1007/s00417-018-3966-0

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