DALK is a partial-thickness corneal transplant that replaces the front layers while preserving the patient’s own endothelium. It is often used for keratoconus and scars that spare the back surface.
Surgical steps
The surgeon removes the diseased stroma down to the clear Descemet membrane. Donor tissue without endothelium is then sutured in place.
- Various techniques are used to separate layers safely
- Preserving the patient’s endothelium reduces rejection risk
- Stitches remain for months and are removed gradually
- Glasses or lenses may still be needed afterwards for fine focus
Advantages and limitations
DALK offers strong structural support with lower rejection rates than full-thickness grafts. However, visual recovery can be slower and surgery more complex.
- Useful for keratoconus, some scars, and stromal dystrophies
- Endothelial cell loss is minimised compared with PKP
- Interface haze may slightly reduce maximum vision in some cases
- Long-term follow-up remains important for suture management
