Corneal Allogeneic Intrastromal Ring Segments (CAIRS): The New Kid on the Block

Abstract

Corneal allogeneic intrastromal ring segments (CAIRS) have recently been introduced as a novel therapeutic modality for keratoconus and corneal ectatic conditions. As with synthetic intracorneal segments, CAIRS are transplanted into intrastromal channel created via femtosecond laser, in order to regularise the corneal geometry, reduce myopia and astigmatism as well as higher-order aberrations, thus ultimately improving visual and topographic parameters. A growing body of clinical evidence supports the efficacy and safety of this approach, and CAIRS has thus become a paradigm shift in keratoconus treatment. This article provides a brief overview of CAIRS, its surgical indication, and graft preparation and possible customisation.

Keywords

CAIRS - Keratoconus - Ectasia - Cornea

Publication History

Received: 01 March 2025

Accepted: 21 May 2025

Accepted Manuscript online:
26 May 2025

Article published online:
21 August 2025

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