Corneal transplantation has evolved from a one-size-fits-all full-thickness replacement into a series of refined, selective procedures tailored to the affected layer of the cornea. Modern surgeons can now restore clarity with minimal invasiveness and faster recovery.
The Era of Penetrating Keratoplasty (PK)
For decades, penetrating keratoplasty (PK) was the gold standard. It involves replacing the entire cornea with a donor graft. While effective, PK carries risks of astigmatism, wound dehiscence, and prolonged visual rehabilitation.
Rise of Lamellar Techniques
Advances in microsurgery and instrumentation gave rise to lamellar keratoplasty, which selectively replaces only diseased layers:
- Deep Anterior Lamellar Keratoplasty (DALK): Ideal for stromal disorders such as keratoconus, preserving the patient’s endothelium.
- Endothelial Keratoplasty (EK): Targets endothelial dysfunction, as seen in Fuchs’ dystrophy.
DSAEK and DMEK — Refining the Art
Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) brought smaller incisions and faster recovery. Later, Descemet’s Membrane Endothelial Keratoplasty (DMEK) refined this further by transplanting only the Descemet membrane and endothelium — just 15 microns thick. DMEK offers faster visual recovery, less rejection, and near-anatomical restoration.
Technological Support
Femtosecond lasers have improved graft preparation precision, and imaging tools such as intraoperative OCT have enhanced graft positioning and interface evaluation. These innovations reduce surgical time and complications.
Postoperative Management
Rejection remains the main concern, though rates have significantly dropped. Topical steroids and improved donor screening enhance long-term graft survival. Some centers are now experimenting with cultured endothelial cells for regenerative therapy.
Conclusion
From PK to DMEK, corneal transplantation has become less invasive, more selective, and more predictable. The future lies in cell-based therapy and bioengineered corneas, promising to eliminate donor dependence altogether.
