Iatrogenic Keratectasia after Refractive Surgery – Causes, Prophylaxis, Therapy

Felix Mathias Wagner; Walter Sekundo

doi:10.1055/a-2073-8478

Klinische Monatsblätter für Augenheilkunde, Table of Contents

Klin Monbl Augenheilkd 2023; 240(06): 783-794
DOI: 10.1055/a-2073-8478

Review/Übersicht

Iatrogenic Keratectasia after Refractive Surgery – Causes, Prophylaxis, Therapy

Article in several languages: English | deutsch

Authors

Felix Mathias Wagner

¹Universitätsaugenklinik Mainz, Mainz, Deutschland

²Universitätsaugenklinik Marburg, Marburg, Deutschland
Walter Sekundo

²Universitätsaugenklinik Marburg, Marburg, Deutschland

Abstract

Iatrogenic keratectasia is induced thinning and protrusion of the cornea after laser refractive surgery. Known risk factors include an excessively thin postoperative residual stromal bed, a thicker flap, or preoperatively undetected evidence of preexisting subclinical keratoconus. The rate of post-refractive ectasia in eyes without identifiable preoperative risk factors is 20 per 100 000 eyes for photorefractive keratectomy, 90 per 100 000 eyes for laser in situ keratomileusis, and 11 per 100 000 eyes for small incision lenticule extraction. Traditional screening tools for preoperative risk include the ectasia risk score system and percentage of tissue alteration. More recent methods include corneal elastography and epithelial mapping, in addition to Artificial Intelligence methods for data analysis. Therapy includes contact lenses, cross-linking, implantation of intracorneal ring segments, penetrating or lamellar keratoplasty, and, in early studies, implantation of corneal lenticules.

Key words

cornea - refractive surgery - ectasia

Full Text

References

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