The cornea is the crystal clear window in the front of the eye.
If a cornea is no longer able to adequately accomplish one or more its functions (transparency, focused imaging, stability), the only available help is the tranplantation of a clear human cornea. A corneal transplantation can be performed full thickness or partial thickness (lamellar).
DALK is a partial-thickness cornea transplant procedure that involves selective transplantation of the corneal stroma, leaving the native deep layers of the cornea (Descemet membrane and endothelium) in place. Similar to PK, the graft is secured with interrupted and/or running sutures and these are then selectively removed post-operatively.
DALK is useful for processes involving the anterior layer (stroma) of the cornea in the presence of healthy endothelium. Examples include corneal ectasia (such as keratoconus in the absence of hydrops), corneal scars that are not full-thickness, and corneal stromal dystrophies.