Comparative Study of Long-term Graft Survival between Penetrating Keratoplasty and Deep Anterior Lamellar Keratoplasty

Abstract Purpose Endothelial failure and immunological graft rejection remain long-term complications leading to late graft failure in Penetrating keratoplasty (PK). Deep anterior lamellar keratoplasty (DALK) has emerged as a viable alternative that enables preservation of the host’s endothelial cells to eliminate risks of endothelial rejection and failure. The aim of this study was to compare long-term graft survival between PK and DALK. Design Retrospective clinical cohort study Methods All consecutive primary grafts of DALKs (n=362) and PKs (n=307) performed for optical indications in a tertiary eye centre from the ongoing prospective Singapore Corneal Transplant Study. 10-year graft survival outcomes were compared. Cases diagnosed with endothelial pathologies were excluded, as DALK was not performed for such cases. Main outcome measure was mean graft survival rate. Results The survival rate for PK was 94.4%, 80.4% and 72.0% at 1, 5 and 10 years; and 95.8%, 93.9% and 93.9% at 1, 5 and 10 years for DALK (p=0.001). PK developed more complications of glaucoma (29.3% vs 11.6%, p Conclusion The 10-year graft survival for primary DALK was superior to PK for corneal pathologies with functional endothelium. Primary DALK results in less post-operative complications and lower rates of graft rejection and failure. This study strengthens the case in favour of performing DALK over PK when possible.