What Is an Endothelial Keratoplasty?

An endothelial keratoplasty is an eye operation in which the innermost layer, or endothelium, of the cornea is removed and replaced by donor tissue. The cornea is the transparent covering of the eyeball, and this type of corneal transplantation may become necessary when diseases such as Fuch's endothelial dystrophy damage the endothelium. Endothelial keratoplasty is also known as a Descemet’s stripping endothelial keratoplasty, which can be abbreviated to DSEK. It represents a simpler option than the traditional treatment for endothelial disease, where the entire central cornea is replaced in what is called a penetrating keratoplasty.

The endothelium contains cells involved in the movement of fluid into and out of the cornea. Accidental injury or disease may cause damage to these cells, leading to swelling of the cornea. As the normally transparent cornea, together with the lens, is involved in bending the light which enters the eye so that it focuses on the retina, a swollen cornea can lead to vision becoming blurred. The cornea itself may also become clouded, and optic keratoplasty may then be required in order to restore normal sight.

Endothelial keratoplasty is a relatively quick cornea transplant method, typically taking less than an hour to perform. Local anesthetic drops are used in the eye before the procedure. The inner, diseased endothelial layer of the cornea is peeled away and a piece of healthy endothelium from a donor is inserted in its place. In order to help the cells of the new endothelial tissue seal in place and bond with the rest of the cornea, a bubble of air is injected into the eye, which pushes the transplant into position.

Following endothelial keratoplasty surgery, it may be necessary to lie flat to allow the bubble of air to keep the transplant tissue in place. This position may have to be adopted as much as possible during the first 24 hours to enable healing to occur. Healing is typically fast, with most of it occurring within the first month. Visual improvement is normally experienced by patients in the first week, but sight could continue to improve for up to six months after surgery.

Advantages of endothelial keratoplasty include the short time required to perform the procedure and the quick recovery, with a rapid return of vision. There is less chance of the transplant being rejected because most of the original cornea is retained. Some of the disadvantages are that the operation is technically demanding and must be carried out by a highly-skilled, experienced surgeon, and that the transplanted corneal tissue might move out of place, making further treatment necessary.