DIFFERENT INDICATIONS ABOUT CORNEAL ALLOGENIC INTRASTROMAL RING SEGMENTS (CAIRS)

To present the efficacy and application of CAIRS implantation as a micro-invasive surgical
technique to manage cases of irregular and high astigmatism in patients intolerant to rigid
contact lenses.

This study includes patients with various astigmatic conditions: congenital Descemet's
membrane tears, pellucid marginal degeneration, and multiple cases of advanced yet stable
keratoconus.

All patients underwent CAIRS under local anesthesia, occasionally supplemented with mild
sedation. The donor graft was prepared using an artificial chamber. The procedure utilized
the Ziemer Z8 laser to create a precise corneal tunnel at a depth of 200-250 microns,
centered on the steepest meridian.

Postoperative outcomes revealed immediate keratometric flattening of up to 20 diopters,
depending on the underlying pathology. This result correlated with rapid visual recovery and
significant reduction in optical aberrations.

CAIRS is a reliable, promising micro-invasive technique, offering an effective alternative
treatment for irregular astigmatism without the associated risks of penetrating keratoplasty.
The absence of adverse effects in this series highlights CAIRS as a valuable approach,
expanding treatment options for patients with severe astigmatic irregularities.

Support for this work was provided by Ziemer.