Three-year clinical outcomes and posterior corneal elevation change after small-incision lenticule extraction in suspicious corneas

Purpose: To determine the long-term clinical outcomes and change in posterior corneal elevation after small-incision lenticule extraction (SMILE) in eyes with suspicious tomographic features. Setting: Hospital clinic. Design: Retrospective, case-controlled, observational. Methods: This study included 43 patients with suspicious corneas (group A), defined by corneal morphology and a final D score from a Scheimpflug camera (Pentacam), and 43 patients with normal corneal topography (group B). Refraction, visual acuity, and posterior corneal elevation over a 6-mm central diameter, including posterior central elevation (PCE), posterior elevation at the thinnest point (PTE), and posterior maximal elevation (PME), were measured preoperatively and at 6 months, 12 months, and 36 months postoperatively. Results: The preoperative spherical equivalent was -5.51 +/- 1.33 D in group A (n = 43) and -5.41 +/- 1.19 D in group B (n = 43). Postoperative uncorrected distance visual acuity was 20/20 or better in 39 (91%) of 43 eyes in group A and 41 (95%) of 43 eyes in group B (P =.160); all eyes in both groups remained stable or had gained corrected distance visual acuity. The mean change in PCE, PTE, and PME at 3 years was -1.22 +/- 2.65 mu m, -1.21 +/- 2.70 mu m, and -1.00 +/- 5.09 mu m in group A and -1.76 +/- 3.25 mu m, -1.60 +/- 3.33 mu m, and -1.56 +/- 5.01 mu m in group B, respectively, indicating a tendency for backward displacement of the posterior surface, whereas the between-group difference was not statistically significant (P =.154, P =.547, and P =.319, respectively). Conclusions: Refraction, visual outcomes, and posterior corneal shift seem comparable between corneas with normal and suspicious tomographic features three years after SMILE. More long-term studies are warranted to corroborate the findings of this study. Copyright (c) 2021 Published by Wolters Kluwer on behalf of ASCRS and ESCRS