Current status of the topography of the sclera: a literature review

Purpose. Although a major part of the anterior surface of the eyeball is formed by the sclera, there is little confirmed data on topography of the sclera compared to the cornea. The goal of this paper was to provide an update of relevant literature published on anatomy and topography of the anterior sclera. Methods. A systematic literature search was conducted in PubMed using the key words “scleral” and “topography.” 66 of the 310 papers dealt with the topic and were used for this present review. In addition, 5 articles from the Germanlanguage non-peer-reviewed literature were included. Results. Several studies have demonstrated the utility of modern measurement and examination techniques, such as optical coherence tomography (OCT), Scheimpflug imaging, or Fourier-based profilometry in the assessment of scleral parameters. These allow a more comprehensive understanding of the structure and shape of the anterior sclera, simplified contact lens selection, prediction of lens fit, and assessment of changes in scleral topography. The shape of the sclera can be influenced by factors such as age, refraction, accommodation, convergence, thickness, stiffness, modulus of elasticity, intraocular pressure, keratoconus and contact lens wear. Conclusion. A comprehensive understanding of the biometric properties and topography of the sclera of the anterior segment of the eye is an essential component for both the design and fitting of scleral as well as soft contact lenses. Keywords Sclera, topography, anatomy, Scheimpflug, profilometry, optical coherence tomography