Strategies for Deep Anterior Lamellar Keratoplasty After Hydrops in Keratoconus
Corneal hydrops affects approximately 2.5% of keratoconus (KC) cases, predominantly young males approximately 25 years of age with steep cones. Often, patients are left with a vision-reducing corneal scar frequently necessitating surgical treatment. Penetrating keratoplasty (PK) has worse survival outcomes in hydrops than in general KC cases. Deep anterior lamellar keratoplasty (DALK) is a nonpenetrating technique believed to achieve equal or better outcomes in visual acuity, graft survival, endothelial rejection rates, and endothelial cell survival in comparison with PK, while maintaining globe integrity and the patients' Descemet membrane (DM) and endothelium. Outcomes for patients with KC are promising. After hydrops, a corneal scar involving DM complicates the ability to perform DALK using standard techniques. So far few case series described successful treatment of hydrops scars with DALK. In this review, we summarize, evaluate, and discuss the current known approaches to DALK in patients after hydrops.