Corneal transplantation, keratoplasty, PKP, DALK, DSEK, DMEK - A State of Sight #9

Isaac Porter, MD from Lowry Porter Ophthalmology explains the basics of corneal transplantation, which is one of the most successful transplants in humans. Patients with cloudy, hazy, swollen, or scarred corneas may benefit from a transplant. Modern surgical techniques now allow the replacement of the entire cornea or selective transplantation of the inner or outer layers.

Welcome to A State of Sight, I’m Isaac Porter from Lowry Porter Ophthalmology and we are continuing to bring you the latest in ophthalmology and eye care from Raleigh, NC. Today, I want to explain corneal transplantation, which is one of the most successful transplant procedures throughout the whole body.
The cornea is the clear shield that covers the front of the eye. Behind the cornea sits the iris, or the colored part of the eye, which is what you see when you look at someone’s eye. Because the cornea is clear it’s a little bit hard to see, but sometimes you can see a reflection of light bouncing off the cornea.
When the cornea becomes cloudy, hazy, or swollen, it interferes with light passing into the eye and can cause poor vision. When this happens, a corneal transplant can help restore vision.
There are several reasons why a corneal transplant may be needed. The most common ones include clouding and swelling after eye surgery, changes in the shape of the cornea, like keratoconus, or some diseases that progressively cause clouding of the cornea that are inherited / genetic diseases.
Other things, like viral infections, can also cause trouble with the cornea and some people that have an injury can get a scar that may interfere with vision.
Fortunately, there are many solutions to these different types of corneal problems and there are several different types of transplants. A lot of these transplant procedures have been developed in the past 10-15 years where we can now selectively transplant different layers of the cornea.
The main types are a full thickness corneal transplant (PKP, penetrating keratoplasty) where the central cornea is removed and replaced with an entirely new cornea from a donor. There’s also the option to transplant just the front layers of the cornea (DALK, deep anterior lameallar keratoplasty) if that is where the problems is, or we can selectively replace the inner layer of the cornea if that’s the only problem (DSEK, Descemet’s stripping endothelial keratoplasty, or DMEK Descemet’s membrane endothelial keratoplasty).
There’s also a different type of transplant, a limbal stem cell transplant, that helps to replace the surface covering of the cornea, the very outermost layers. This is one of the few types of stem cell transplants that we can do in humans.
I would like to give you more details about each of these types of transplants in future episodes of A State of SIght, but until then if you have any questions or comments, please post below. I hope to see you again. Until next time, good health and good sight.