Penetrating Keratoplasty for Keratoconus With and Without Resolved Corneal Hydrops: Long-term Results

To evaluate the long-term risk of endothelial rejection, graft survival, and associated factors following penetrating keratoplasty (PK) for keratoconus, with and without prior resolved corneal hydrops.

Retrospective cohort study.

Primary outcome measures were endothelial rejection-free survival and failure-free survival. Secondary outcome measures were corneal neovascularization following hydrops and complications following PK.

A total of 245 eyes underwent PK for keratoconus with mean follow-up of 5.6 ± 3.6 years. Eyes with prior hydrops (n = 74) had lower endothelial rejection-free survival rates compared with eyes without prior hydrops: 86.5% ± 4.0% vs 86.5% ± 2.6% at 1 year, 61.0% ± 6.2% vs 76.9% ± 3.3% at 5 years, and 45.8% ± 10.1% vs 70.9% ± 4.3% at 10 years, respectively (P = .023). Multivariate analysis identified factors associated with endothelial rejection as age ≤25 years (P = .017), corneal neovascularization (P = .001), donor trephination size >8 mm (P = .017), and poor clinic attendance (P = .015). There was no difference in the failure-free survival rates with and without prior hydrops: 98.6% ± 1.3% vs 97.1% ± 1.3% at 1 year, 97.3% ± 1.9% vs 95.1% ± 1.9% at 5 years, and 97.3% ± 1.9% vs 92.2% ± 2.7% at 10 years, respectively (P = .42). Corneal neovascularization was present at the time of PK in 44.6% of eyes with prior hydrops and 7.6% without prior hydrops (P < .001).

Corneal neovascularization, a frequent complication of corneal hydrops, was associated with increased risk of endothelial rejection following PK. However, allograft survival was similar in eyes with and without prior hydrops.