Precut Post–Laser In Situ Keratomileusis / Photorefractive Keratectomy Donor Corneas for Use in Endothelial Keratoplasty: Potential Impact of Postcut Morphology on Visual Outcomes

Abstract

To evaluate the accuracy, complication rates, cut quality, and degree of induced hyperopic shift of eye bank-prepared post-laser insitu keratomileusis (LASIK)/photorefractive keratectomy (PRK) donor corneas compared to those of non-post-LASIK/PRK donor corneas. The cut accuracy and failure rates of all post-LASIK/PRK donor cornea tissue processed for use in Descemet stripping automated endothelial keratoplasty (DSAEK) from January 2012 through December 2016 were compared to control cornea donor tissue. Corneas were analyzed for regularity and morphology of cut using anterior segment optical coherence tomography images. Using a mathematical model, the hyperopic shifts induced by post-LASIK/PRK donor lenticules were compared to the control corneas. During the study period, 733 post-LASIK/PRK and 10 437 non-post-LASIK/PRK donor corneas were processed for DSAEK. Cut accuracy and quality were similar (P > .05), but there was an increased tissue wastage rate of 5.0% compared to 2.2% (P < .000001). For tissue < 100μm in central thickness (P= .0001), and for tissue between 100 and 150μm in central thickness (P= .0023), the difference between central and peripheral thickness when comparing the post-LASIK/PRK and control corneas was statistically significant. These differences resulted in a 1.96 diopter (D), 1.60 D, and 2.35 D hyperopic shift when using donor corneas 100μm, 125μm, and 150μm thick, respectively, from post-LASIK/PRK donors compared to 1.11 D, 0.38 D, and 1.96 D from control donors. Eye bank technicians and surgeons should be aware of the increased risk of tissue wastage when cutting post-LASIK/PRK corneas compared to non-post-LASIK/PRK donors. Surgeons should also be aware of the theoretical increase in hyperopic shift when using post-LASIK/PRK donor corneas compared to non-post-LASIK/PRK donors when cut to less than 150μm. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.