Keratoconus: Ocular surface considerations, from bench to bedside

Aims/Purpose: This comprehensive systematic narrative study is aimed to describe the close interactions between the ocular surface and keratoconus with its vast spectrum of diagnostic and treatment techniques, both basic and clinical. Methods: This investigation searched PubMed, Scopus, Cochrane, Embase, and Web of Science for relevant papers published up to January 2023. The systematic review used MeSH and non‐MeSH terms. Unrestricted language and publishing schedule. After a comprehensive search, all of the search results were imported into Endnote software after a thorough search. Duplicate and less relevant citations have been eliminated in Endnote. In addition to the databases indicated, we searched Google Scholar for “Ocular surface” AND ((keratoconus) OR (“pellucid marginal degeneration”) OR (“corneal ectasia”) OR (“iatrogenic ectasia”)). Results: Treating dry eye, MGD, and blepharitis may slow KC progression and relieve symptoms. Eye rubbing and mechanical injury could spread bacteria to the eyelids, causing blepharitis. Tarsorrhaphy is the most powerful manoeuvre to help heal epithelial defects, especially in moderate and severe forms of DED. Use high‐quality eyedrops, especially preservative‐free ones, to increase tissue viscosity on the ocular surface and protect tear film to reduce epithelium injury before and after surgery. Finally, Vitamins, minerals, metal ions, and antioxidants may prevent dry eye and KC. In addition, improper air quality, wind, pollution, low humidity, watching TV, reading, and surgical procedures can cause dry eye illness, increase MMP‐9 and IL‐6 and decrease EGF during exacerbation. Conclusions: This is the first systematic narrative review to explore the mutual interaction between the ocular surface and KC and the wide spectrum of diagnostic and therapeutic options. Dry eye and tear film instability have been documented as a non‐ectatic differential diagnosis for KC and ectatic disorders. Nonetheless, KC and DED are both common topics. Future research should look into the effect of pre‐treating ocular surface health on postoperative outcome and the efficacy of the therapeutic strategy in reversing KC ocular surface changes.