To evaluate the refractive predictability and efficacy of Descemet membrane endothelial keratoplasty (DMEK) for patients with previous laser refractive surgery.
We retrospectively reviewed our cohort of endothelial keratoplasty surgical cases. We identified 21 eyes that underwent laser-assisted in situ keratomileusis (n = 17) or photorefractive keratectomy (n = 4) and were treated with DMEK for endothelial failure. Patients were analyzed preoperatively and at 6 months postoperatively for changes in visual acuity, refraction, and corneal topography.
Six months after surgery, eyes significantly improved to a mean best-corrected visual acuity of 20/23 (P < 0.001). Mean astigmatism amplitude changed from 1.13 ± 0.96 preoperatively to 0.92 ± 0.51 diopters postoperatively (P = 0.28). However, shifts in the axis of corneal astigmatism ranged from 1 to 70 degrees, with 6 eyes (30%) showing an axis shift of more than 30 degrees. Spherical equivalents in nontriple procedures remained unchanged (n = 16; P = 0.69) at 6 months.
DMEK and DMEK triple procedures are predictable in patients with previous refractive surgery achieving good visual results. However, refraction after the use of toric intraocular lenses may be unpredictable because of the variability in changes of the magnitude and axis of corneal astigmatism; we recommend extreme caution in the use of the toric intraocular lens in this group of patients and proper counseling for possible individual postoperative residual astigmatism.