Corneal cross-linking

Topic Status Complete

Epithelium-off corneal crosslinking to treat adults with keratoconus

Outcome of the appraisal


The evidence about epithelium-off corneal cross-linking (CXL) to treat adults with keratoconus is inconclusive. There is insufficient evidence to show that CXL is effective in the long term. HTW advises that routine provision is not currently supported. Research is recommended into the long term effectiveness and cost effectiveness of epithelium-off CXL in adults, compared with no treatment.

Why was this topic appraised?


This topic was proposed by Dr Kelechi Nnoaham, Director of Public Health, Cwm Taf University Health Board, and submitted to HTW by the Welsh Health Specialised Services Committee (WHSSC) to support evidence-informed decision making over provision of epithelium-off corneal crosslinking within NHS Wales.

Plain language summary


HTW assessed epithelium-off corneal crosslinking to help decide whether it should be made available to treat adults in NHS Wales.

Keratoconus is a condition that affects shape of the cornea (the front of the eye ball), which develops in young people. It causes vision problems such as short-sightedness, blurred vision and light sensitivity.

Corneal crosslinking aims to prevent keratoconus from getting worse over time, or to slow its progression. However, when these procedures involve removal of the outermost layer (‘epithelium-off’) there is uncertainty about how well they work. There’s not enough evidence to show long term effectiveness when compared with no treatment.

HTW’s Guidance doesn’t support routine use of this procedure in adults who have keratoconus.

Evidence Appraisal Review

EAR002 (02.2018)

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GUI002 (05.2018)

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