Comparison of corneal deposits after LASIK and PRK in eyes with granular corneal dystrophy type II

PURPOSE: To compare the characteristics of corneal deposits in eyes with granular corneal dystrophy type II (Avellino corneal dystrophy) after LASIK and photorefractive keratectomy (PRK). METHODS: Patients with heterozygous granular corneal dystrophy type II were examined with slit-lamp microscopy for recurrence of granular corneal dystrophy type II after uneventful LASIK and PRK surgery. One particular case involved bilateral incomplete flaps after LASIK, resulting in excimer laser ablation under the flap in one area and surface ablation in another area of both eyes. Deoxyribonucleic acid sequencing analysis in all patients confirmed the heterozygous status of granular corneal dystrophy type II. RESULTS: An abundance of coarse, white opacities consistent with granular corneal dystrophy type II were observed along the interface in all of the LASIK cases. In comparison, only a mild increase in opacities was noted in the PRK cases. In the LASIK case with bilateral incomplete flaps, abundant opacities were present in both corneas along the interface of the LASIK flap, and a minimal increase of stromal opacities was noted where no LASIK flap was present. CONCLUSIONS: Exacerbation of granular corneal dystrophy type II deposits occurred in the corneal stroma to a much greater degree after LASIK compared to surface ablation surgery.