Histopathological Changes in Corneal Ectasia

Abstract

Corneal ectasia comprises keratoconus, keratoglobus, pellucid marginal degeneration, and iatrogenic keratectasia. In all forms of corneal ectasia, there is a thinning of the cornea, usually accompanied by steepening of the cornea, leading to irregular astigmatism. Here, we provide an overview of histopathologic alterations of the various corneal ectasias. Furthermore, histologic changes after surgical procedures that are performed in severe cases of corneal ectasia, such as corneal cross-linking and penetrating keratoplasty (pKPL), as well as refractive surgical procedures that may lead to postsurgical ectasia are presented. In addition to a literature review, histopathologic archival material was reviewed and examined to illustrate the specific histologic changes.

Key words

keratoconus - cross-linking - keratoplasty - post-LASIK ectasia - PMD

Publication History

Received: 29 November 2022

Accepted: 02 February 2023

Accepted Manuscript online:
22 February 2023

Article published online:
05 May 2023

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