Title : Systematic review on the use of scleral lenses and soft contact lenses in the management of keratoconus
Abstract:
Introduction and Aims: Keratoconus is the most common primary ectasia, progressive corneal ectasia in which central or paracentral thinning of the corneal stroma occurs, leading to steepening of the corneal surface and irregular astigmatism. Management of this condition is largely dependent on the severity of disease; with mild cases being managed with glasses, moderate cases with contact lenses and severe cases requiring surgery and corneal transplantation. Most cases are being managed with contact lenses, and with the development of more techniques in contact lens engineering has allowed for customizable lenses to be developed. In this systematic review, we will be reviewing the literature on the performance of Scleral Contact Lenses and Soft Contact Lenses, to aid in clinical decision making.
Materials and Methods: A literature search was performed in both PubMed and Ovid MEDLINE databases for studies investigating either visual outcomes or patient reported comfort outcomes of Scleral Contact Lens use or Soft Contact Lens wear. Exclusion criteria were: Retrospective studies, Studies not available in English language, Non-peer reviewed articles, Presentation Abstracts and Publications accepted before 2000. Data extraction and thematic analysis was performed to identify comparative themes on the included literature.
Results: A total of 307 articles were returned from both databases. Through abstract screening and full text screening, a total of 4 publications were included: 3 investigating the performance of Scleral Lenses and 1 investigating the performance of Soft Contact lenses. It was shown that the use of scleral lenses significantly improved subjective Quality of Life (QoL) of patients and objective Visual Acuity as well as improvements in High Order Aberrations in vision. Evidence for soft contact lens use was comparatively weaker, with no statistically significant increase in measured visual acuity in its use vs habitual contact lenses.
Conclusion: This review confirms the efficacy of Scleral Contact Lenses in the management of moderate keratoconus. However there is a need for more investigation in the performance of Soft Contact Lenses in the mild-to-moderate keratoconus population as there is sufficient evidence to suggest this to be both easier to insert on the eye surface and more comfortable whilst in use.
