Anterior Lamellar Keratoplasty and Penetrating Keratoplasty for Keratoconus: An IRIS (Intelligent Research in Sight) Registry Analysis

Purpose: The aim of this study was to compare preoperative determinants of procedure selection and long-term outcomes between anterior lamellar keratoplasty (ALK) and penetrating keratoplasty (PKP) in patients with keratoconus in the United States. Methods: A total of 10,405 eyes from patients with keratoconus undergoing corneal transplantation were included from the Intelligent Research in Sight Registry, comprising 1005 eyes that received ALK (mean age 40.0 ±15.5 years) and 9400 eyes that received PKP (mean age 44.3 ±16.4 years) between January 1, 2013, and December 31, 2020. Univariate and multivariable logistic regression analyses were performed to identify demographic and clinical factors associated with the selection of ALK versus PKP. Results: In multivariable analysis, older age (50–59 years: odds ratio [OR]: 0.05; 95% confidence interval [CI]: 0.00–0.88; ≥70 years: OR: 0.01; 95% CI: 0.00–0.44), male sex (OR: 0.28; 95% CI: 0.09–0.90), and Medicaid insurance (OR: 0.11; 95% CI: 0.02–0.55) were significantly associated with lower odds of undergoing ALK. Graft failures (as measured by the incidence of regrafts) and rejections were significantly less frequent in ALK at 90 days (failure: 3.3% vs. 12.6%, P P P P Conclusions: In the United States, younger patients are more likely to receive ALK. Other socioeconomic factors such as ethnicity and insurance coverage may also play an important role. However, our data suggest that ALK may not result in improved postoperative outcomes compared with PKP over 5 years.