Abstract
Keratoconus is a progressive eye disorder primarily affecting individuals in adolescence and early adulthood. The ectatic changes in the cornea cause thinning and cone-like steepening leading to irregular astigmatism and reduced vision. Keratoconus is a complex disorder with a multifaceted aetiology and pathogenesis, including genetic, environmental, biomechanical and cellular factors. Environmental factors, such as eye rubbing, UV light exposure and contact lens wearing, are associated with disease progression. On the cellular level, a complex interplay of hormonal changes, alterations in enzymatic activity that modify extracellular membrane stiffness, and changes in biochemical and biomechanical signalling pathways disrupt collagen cross-linking within the stroma, contributing to structural integrity loss and distortion of normal corneal anatomy. Clinically, keratoconus is diagnosed through clinical examination and corneal imaging. Advanced imaging platforms have improved the detection of keratoconus, facilitating early diagnosis and monitoring of disease progression. Treatment strategies for keratoconus are tailored to disease severity and progression. In early stages, vision correction with glasses or soft contact lenses may suffice. As the condition advances, rigid gas-permeable contact lenses or scleral lenses are prescribed. Corneal cross-linking has emerged as a pivotal treatment aimed at halting the progression of corneal ectasia. In patients with keratoconus with scarring or contact lens intolerance, surgical interventions are performed.
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Introduction (V.J., R.B.S. and F.A.W.); Epidemiology (V.J., R.B.S., S.K., N.S. and F.A.W.); Mechanisms/pathophysiology (V.J., R.B.S., S.K., F.H. and H.S.D.); Diagnosis, screening and prevention (V.J., R.B.S., N.S., F.A.W., F.H. and H.S.D.); Management (V.J., R.B.S., S.K., N.S., F.H. and H.S.D.); Quality of life (V.J., R.B.S. and F.A.W.); Outlook (V.J., R.B.S. and H.S.D.); overview of the Primer (V.J.).
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F.H. is the chief scientific officer and an equity holder of EMAGine AG (Zug, Switzerland) and co-inventor of the Patent Cooperation Treaty (PCT) applications CH2012/0000090 (granted on 21 November 2018) and CH2014/000075 (granted on 20 November 2019) regarding corneal cross-linking technology. There are no direct or indirect references pertaining to the commercial entity’s work or the intellectual properties in this work that could directly undermine the objectivity, integrity and value of this work, through a potential influence on the judgements and actions of the authors regarding objective data presentation, analysis and interpretation. The other authors declare no competing interests.
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Singh, R.B., Koh, S., Sharma, N. et al. Keratoconus. Nat Rev Dis Primers 10, 81 (2024). https://doi.org/10.1038/s41572-024-00565-3
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DOI: https://doi.org/10.1038/s41572-024-00565-3
