Cornea Transplant

Who needs a cornea transplant?

There are several reasons why your eye doctor would recommend a cornea transplant, including:

• To repair the cornea following injury or perforation
• To relieve chronic pain associated with a condition called bullous keratopathy
• To treat corneal damage resulting from eye diseases or medical conditions (such as an infection unresponsive to medication or also from conditions causing thin, clouded, or abnormally shaped corneas)
• To increase the cornea’s focusing capacity and thus improve vision in patients with corneal swelling following cataract surgery (a condition known as Pseudophakic Bullous Keratopathy)
• To address severe Keratoconus, a condition in which the middle of the cornea thins, weakens, and eventually bulges outward, causing focusing problems

Are all cornea transplants the same?

Yes and no.  A cornea transplant replaces a diseased or injured cornea with healthy corneal tissue from a

cadaver donor.

The donated cornea is processed through an eye bank and is even safer than receiving a blood transfusion, which is very safe these days. What's more, a cornea doesn’t need to be tissue matched, like a heart or a kidney does. This is because the cornea has no blood vessels which greatly decreases its risk of tissue rejection.

There are several surgical approaches to cornea transplants (known as corneal keratoplasty). These can range from transplantation of just the inner corneal lining to transplantation of all layers of the cornea (called a full-thickness transplant).

The appropriate procedure for you is determined following a comprehensive evaluation that includes specialized imaging of your cornea and a lengthy conversation about your eye health with your ophthalmologist.

At AGEI we perform three types of cornea transplants to address a wide variety of conditions. Here's a brief explanation of each approach:

Intralase Enabled Keratoplasty (IEK)

IEK is a full-thickness transplant approach that utilizes a laser to prepare both the donor and the recipient's eyes for the transplant. It does so by ensuring that the shape of the graft tissue taken from the donor exactly matches (like a puzzle) the graft deposit site in the recipient´s cornea.

Advantages of the IEK blade-free approach over conventional surgery include:

1. 1. The interlocking graft design results in a transplant site that is stronger than the one achieved by conventional surgery
   2. IEK is associated with improved vision outcomes and reduced risk of postop astigmatism.
   3. IEK requires fewer stitches which also come out sooner
   4. IEK recovery is faster and patients can return to work sooner

Penetrating Keratoplasty (PK) 

PK is another full-thickness transplant procedure in which the surgeon removes and replaces all layers of the diseased cornea with clear, healthy donor tissue. It can take up to one year for your vision to reach its maximum potential following this surgery.

Descemet’s Stripping Endothelial Keratoplasty (DSEK)

DSEK removes and replaces diseased tissue from the deepest of the three corneal layers, called the endothelium, along with its thin protective coating called the Descemet membrane. That’s why it’s known as a partial thickness transplant.

The advantages of a DSEK include:

It has a faster healing time than a full-thickness transplant because less than one-tenth of the cornea’s thickness is replaced. Vision is recovered in a matter of weeks, as opposed to months required for a full-thickness cornea transplant. The post-op eye is stronger because less tissue is replaced and so it is structurally sturdier than if it had undergone a full-thickness transplant. The likelihood of rejection is lower than with IEK or PK.

Descemet’s Membrane Endothelial Keratoplasty (DMEK)

The DMEK procedure removes and replaces diseased tissue from the deepest of the three corneal layers, called the endothelium, along with its thin protective coating called the Descemet membrane. That’s why it’s known as a partial thickness transplant.

Other advantages of a DMEK include:

1. 1. Faster healing time than a full-thickness transplant because less than one-tenth of the cornea’s thickness is replaced. Vision is recovered in a matter of weeks, as opposed to months required for a full-thickness cornea transplant.
   2. Outstanding visual acuity is possible because only a minute amount of corneal tissue is replaced (the graft is about ten microns thick).
   3. The post-op eye is stronger because less tissue is replaced and so it is structurally sturdier than if it had undergone a full-thickness transplant.
   4. The likelihood of rejection is lower than with IEK or PK. In fact, patients usually don’t need to continue using steroid eye drops to prevent rejection after one-year post-op.

Will a cornea transplant give me 20/20 vision?

The primary goal of a cornea transplant is to provide patients with a healthy functioning cornea. Your post-op vision depends on many variables and it may be a bit worse for several months as your eye adjusts to the new cornea. This is really one of those "miracles of modern medicine".

Most people needing a cornea transplant require some assistance for vision correction with either glasses or contact lenses. Once the outer layer of your cornea has healed (from weeks to months after surgery) your eye doctor will see if there are any adjustments that can be made to further improve your vision.