Keratoplasty for Keratoconus in Young Patients: Demographics, Clinical Features, and Post-transplant Outcomes

Abstract

To examine pretransplant findings and outcomes of corneal transplants for keratoconus in children. Retrospective cohort (national registry) study. Data on all patients aged 16 or younger (n=170) who had a first transplant for keratoconus between 2003 and 2018 in all corneal transplant centers in the UK were compared to adult patients aged 17 and older (n=7,191). The influence of demographic variables, pretransplant corneal findings, and transplant type on 2-year visual, rejection-free, and transplant survival outcomes was examined. Children had poorer pretransplant visual acuity and higher rates of corneal vascularization and ocular surface disease than adults. However, 2-year post-transplant corrected visual acuity reached 20/20 or better in 35% of children compared to 28% of adults (P=.1). Transplant rejection and failure rates were 11% (P=.79) and 3% (P=.31), respectively, for children, which were comparable to rates for adults. Endothelial rejection was reported following penetrating keratoplasty (PK) in 13% of children (10% in adults). Irreversible rejection was not recorded for any transplant in a child. Despite a lack of difference in transplant outcomes, there was a significant age effect in the Cox regression model for transplant rejection, such that for every 5-year increase in age there was a 6% reduction in the hazard of rejection. Transplant survival following anterior lamellar keratoplasty and PK in children was similar. Young keratoconus patients have excellent transplant outcomes and visual results comparable to adults. Overall, the hazard of rejection was found to decrease with advancing age. However, in this large cohort of young patients with keratoconus and poor vision, there is no evidence of outcome advantage in delaying transplant until adult years.