​​DSEK stands for Descemet’s Stripping Endothelial Keratoplasty and refers to a thin corneal layer called Descemet’s Membrane, named for an eighteenth century French doctor. This surgery is a corneal transplant or graft of this one layer, rather than of the full corneal thickness, as is done in a standard corneal transplant. Please see Eye Anatomy: The Cornea for more information.
 

There are three main corneal layers:

•     The epithelium, which is kept moist and clean by the eye’s tears
•     The stroma, where laser vision correction is done, as it is a very stable layer
•     The endothelium, which controls the fluid content of the whole cornea

In addition to these layers, there are two very thin layers, one on each side of the stroma. Bowman’s layer is a tough, protective layer of collagen over the stroma. Descemet’s membrane is beneath the stroma and is called a basement membrane. It connects the stromal cells with the endothelial cells.

Since the endothelium pumps excess aqueous fluid out of the cornea which would otherwise cause swelling and cloudy vision, it is an important layer for clear vision. Descemet’s membrane helps to protect the endothelium.

Aqueous fluid provides nutrients to the cornea which has no blood vessels. They would obstruct vision. Oxygen is received by the corneal epithelium from the air.