Dan Liu, MD

Milford Franklin Eye Center

In May 2023, a landmark surgery was performed at NYU Langone Health: a whole eye transplant. During this surgery, the entire eye – in addition to a portion of the face – was transplanted from a donor into a living human recipient for the purposes of facial reconstruction. While we are likely decades away from performing eye transplants that can restore vision, there are more than 49,000 transplants of a different kind performed in the United States annually which can successfully improve vision and save sight: corneal transplants. 

What is the cornea?

The cornea is the transparent, dome shaped surface that acts as the front window to the eye. It plays a crucial role in focusing light rays entering the eye in order to allow us to see clearly. When the cornea is damaged, it can become scarred, swollen, or opaque. In these cases, the visual effects can vary from increased light sensitivity, blurry vision, or even impaired vision to the point of blindness. Fortunately, for many individuals experiencing corneal damage, a corneal transplant, also known as a keratoplasty, may offer the opportunity to restore vision.

Who needs a corneal transplant?

There are various conditions, both genetic and acquired, that can affect the cornea and necessitate a corneal transplant. Common conditions include:

• Corneal dystrophies: These are inherited conditions that cause progressive clouding or scarring of the cornea. Fuchs’ dystrophy is the most common of these dystrophies, which often runs in families. This is a condition in which the innermost layer of cells in the cornea, the endothelial cells, no longer function in keeping the cornea clear. As a result, fluid can build up in the cornea, causing it to be swollen and cloudy. Some patients with Fuchs’ dystrophy experience debilitating glare, whereas other patients can experience significant loss of vision.

• Keratoconus is a common condition for which corneal transplants are performed. In patients with keratoconus, the cornea becomes increasingly cone shaped over time rather than remaining dome shaped. This can lead to loss of vision as light rays bend or refract aberrantly off the irregularly shaped cornea. Individuals with keratoconus may experience progressive astigmatism and a decrease in vision.

• Other acquired conditions that may affect the health and clarity of the cornea include eye infections which can cause significant scarring, or even previous eye surgeries that can result in damage to the cornea. 

What is a corneal transplant?

In diseases in which the cornea cannot be repaired with medications alone, an ophthalmologist who specializes in performing corneal transplants can restore the clarity and health of the cornea, as well as vision. In these sight saving surgeries, the diseased cornea is replaced with a clear, healthy cornea from a human donor who has generously chosen to donate their organs after death. Luckily, in the United States, there is a well established infrastructure for tissue procurement such that people who require corneal transplants do not need to be on a prolonged waiting list in order to have surgery. By replacing the damaged tissue, a corneal transplant can significantly improve a person’s vision, enhance their quality of life, and reduce symptoms like pain or sensitivity to light. In this era of modern medicine, corneal transplants are very successful and last up to 10 to 15 years, with many lasting more than 30 years.

Are there different kinds of corneal transplants?

Since the introduction of corneal transplants in the 1900s, these surgeries have evolved to become more efficient with faster healing times and better visual outcomes. Corneal transplants can be full thickness or partial thickness transplants.

• Penetrating keratoplasty (PK): Also known as a full thickness corneal transplant, this is the most traditional form of corneal transplant. In PK, the diseased cornea is removed by the surgeon, the donor cornea is sized to fit the patient’s eye, and stitches are used to place the donor cornea in the eye. The surgery is performed when the cornea is severely scarred or damaged, affecting all of its layers.

• Descemet’s Stripping Endothelial Keratoplasty (DSEK): In DSEK, only the innermost layer of the cornea, called the endothelium, is replaced. The rest of the corneal layers remain intact. This surgery is often used to treat conditions that affect the endothelium, such as Fuchs’ dystrophy.

• Descemet’s Membrane Endothelial Keratoplasty (DMEK): DMEK is a more advanced version of DSEK and is considered one of the most effective corneal transplant procedures for treating endothelial dysfunction. In DMEK, only the thinnest layer of tissue with endothelial cells are transplanted. Because of its precision, DMEK has a faster recovery time and better visual outcomes than traditional PK or DSEK procedures. 

Do I need a corneal transplant?

To determine whether you would benefit from a corneal transplant, a thorough evaluation by an ophthalmologist is necessary to determine whether a transplant is appropriate. At Milford Franklin Eye Center, we have corneal transplant surgeons who perform additional testing to evaluate the patient’s eye health, including measurements of corneal thickness and imaging scans. We also have established relationships with eye banks, which are organizations that procure donated tissue and screen for quality. 

For more details, see our ad on page 16.

Sponsored articles are submitted by our advertisers. The advertiser is solely responsible for the content of this article.