Comparison of keratoplasty outcomes at the scar versus edema stages of keratoconus

Purpose: To assess the outcomes of deep anterior lamellar keratoplasty or penetrating keratoplasty at the scar and the edema stages. Methods: Forty-five patients (45 eyes) with keratoconus scar stage (scar group, n=26; penetrating keratoplasty a subgroup, n=7; deep anterior lamellar keratoplasty b subgroup, n=19) and keratoconus edema stage (edema group, n=19; penetrating keratoplasty c subgroup, n=12; deep anterior lamellar keratoplasty d group, n=7) who received penetrating keratoplasty or deep anterior lamellar keratoplasty from 2000 to 2022 were retrospectively studied. At 1, 6, and 12 months after surgery, the best-corrected visual acuity, astigmatism, spherical equivalent, corneal endothelial cell density, and complications were analyzed. Results: The best-corrected visual acuity and average corneal endothelial cell loss rate were not significantly different between the scar and edema groups (p>0.05). At 6 and 12 months after surgery, the astigmatism and spherical equivalent in the scar group were significantly lower than those in the edema group (p<0.05). The spherical equivalent of the deep anterior lamellar keratoplasty b subgroup was lower than that of the penetrating keratoplasty a subgroup in the scar group 6 months after surgery (p<0.05). In the edema group, there was no significant difference in spherical equivalent between subgroups (p>0.05). There were no significant differences in best-corrected visual acuity and astigmatism between subgroups within the two groups (p>0.05). In comparison to the scar group, the edema group experienced more complications. According to a survival analysis, there was no statistically significant difference between the scar group and the edema group regarding the progression of vision. Conclusions: In terms of the outcomes and prognosis for vision after keratoplasty with edema stage and scar stage, deep anterior lamellar keratoplasty may be as effective as penetrating keratoplasty.