Corneal transplant: DMEK, DALK and keratoplasty
A corneal transplant replaces a diseased, cloudy or distorted cornea with healthy donor tissue. The surgery has changed profoundly: today we often replace only the affected layer, which speeds up recovery and lowers the risk of rejection. Here are the main techniques and their indications.
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Why transplant the cornea?
The cornea is transparent and lets light through. When it turns cloudy, swollen or too distorted, vision drops. A transplant is considered when other treatments are no longer enough — for example in advanced Fuchs' dystrophy, advanced keratoconus, or scarring after infection or trauma.
Endothelial transplants: DMEK and DSAEK
The endothelium is the thin inner layer of the cornea that keeps it "dry" and clear. When it fails (Fuchs' dystrophy, swelling after surgery), we replace only this layer.
- DMEK — transplant of the Descemet membrane and endothelium only. It is the thinnest, most selective technique, giving fast visual recovery and a low risk of rejection.
- DSAEK — a slightly thicker endothelial transplant, sometimes preferred in certain anatomical situations.
Deep anterior lamellar transplant: DALK
DALK replaces the front layers of the cornea (epithelium and stroma) while keeping the patient's own healthy endothelium. It is particularly suited to keratoconus and superficial opacities. Its major advantage: by preserving the patient's endothelium, it removes the risk of endothelial rejection, the most feared form.
Penetrating keratoplasty
This is the "classic" transplant, replacing the full thickness of the cornea. It remains indicated when all layers are affected (deep opacities, certain scars). Recovery is longer and rejection monitoring more careful.
After the transplant: recovery and follow-up
Recovery depends on the technique: often fast after DMEK, more gradual after DALK or a penetrating transplant. Eye drops and regular follow-up help prevent and detect any rejection, which is treated effectively when caught early. It is important to report any drop in vision, redness or pain without delay.
Are you a healthcare professional? For an in-depth review, see the full course "Corneal transplantation in 2026" — DALK, DMEK/DSAEK/PDEK techniques, rejection immunology, keratoprostheses.
This page is for general information and does not replace a medical consultation. The choice of transplant technique is always individualised after a complete examination. Pr Eric E. Gabison — corneal and ocular surface surgery, Fondation Adolphe de Rothschild, Paris.