What Is a Corneal Transplant? A Clear Patient Explanation

Everything You Need to Know About Corneal Transplant Surgery

The cornea is the clear layer at the front of the eye that acts as the eye's primary lens.

It helps focus incoming light so you can see clearly.

When the cornea is damaged, it may need to be replaced through corneal transplant surgery.

Dr. Shaarawy removes all or part of the damaged cornea and replaces it with healthy donor tissue.

The replacement cornea comes from individuals who chose to donate their corneas after death

and is imported from accredited eye banks in the United States.

A corneal transplant — also called corneal grafting — can restore vision, reduce pain, and improve the appearance of a damaged cornea (which can give the eye a white, opaque look).

Who Might Need a Corneal Transplant?

Light passing through a damaged cornea can scatter and produce blurred, hazy vision.

This may result from conditions such as:

- Corneal scarring from injury or infection

- Corneal ulcers from infection

- Keratoconus, where the cornea bulges outward into a cone shape

- Corneal thinning or swelling (edema)

- Inherited corneal diseases such as Fuchs dystrophy

- Complications from previous eye surgery, such as cataract removal

- Dr. Shaarawy will discuss the specific procedure best suited to your case.

Main Types of Corneal Transplant

1. Penetrating Keratoplasty (PKP)

This full-thickness corneal transplant replaces the entire cornea with a healthy, clear donor cornea.

It is performed when the cornea has sustained severe damage that affects vision

and there is no surgical alternative. The procedure can be done under local

or general anesthesia and takes about an hour. Roughly 8 mm of the cornea is replaced

using either a trephine or a femtosecond laser, then secured with sutures —

typically 16 stitches. After surgery, vision will be blurry for several days,

and the sutures usually stay in place for about a year.

Artificial cornea

2. Deep Anterior Lamellar Keratoplasty (DALK)

In this type of transplant, about 99% of the cornea is replaced with donor tissue,

but not the entire thickness as in a full PKP.

It is a technically demanding procedure: the surgeon separates the back layers of the cornea

(Descemet's membrane and the endothelium) and preserves them, replacing only the rest of the corneal layers.

This technique is used as an alternative to penetrating keratoplasty

when the back layers of the cornea are still healthy.

The donor tissue is then secured with sutures. A key advantage of DALK is that the rate of graft rejection approaches zero,

and steroid drops can typically be tapered earlier.

One of the most common indications for DALK is keratoconus.

3. Endothelial Keratoplasty (EK) — Posterior Lamellar Transplant

In this type of corneal transplant, only the back (endothelial) layer of the cornea is replaced

(Descemet's membrane and the endothelium).

To put it simply: it is the opposite of DALK.

EK is also a highly specialized procedure and includes two main variants:

The first — DSAEK — replaces Descemet's membrane and the endothelium

along with a thin layer of corneal stroma.

The second — DMEK — replaces only Descemet's membrane and the endothelium.

Both DSAEK and DMEK use the same overall strategy to treat diseases affecting

the back layer of the cornea — most commonly endothelial decompensation

that can occur after cataract surgery,

which can disrupt the back of the cornea.

The endothelium is what keeps the cornea clear

by pumping fluid out and preventing corneal swelling,

especially when the endothelial cell count is too low

due to disease or damage. At that point, the cornea begins to swell and vision becomes hazy.

The surgery is performed under local or general anesthesia

through a small (about 2 mm) incision in the eye.

The damaged endothelial cells and their layer are removed,

and Dr. Shaarawy replaces them with healthy donor endothelial tissue,

secured in place with an air or gas bubble.

The patient must lie flat on their back for about two hours after surgery,

then keep the face directed upward to keep the gas bubble in place,

since the bubble helps the donor tissue adhere to its proper position.

During his PhD fellowship at Legacy Devers Eye Institute in the United States,

Dr. Shaarawy worked alongside Dr. Mark Terry on these complex surgeries

and was the first surgeon to perform DMEK using the S-Stamp technique in Egypt

(a technique developed at Legacy Devers Eye Institute, where he trained).

He has presented this work at numerous local and regional conferences.

*In severe cases, an artificial cornea (keratoprosthesis) may be implanted (as shown above) to avoid graft rejection.

Recovery

Some blurriness in vision after a corneal transplant is normal

until the eye fully heals. Mild redness and light sensitivity are also expected.

You may experience itching for a few days,

although some patients have no discomfort at all.

Dr. Shaarawy will prescribe eye drops

to reduce inflammation and lower the risk of infection.

Other medications may be prescribed to ease any pain.

He will also examine the eye on the first day after surgery,

several times during the following two weeks,

and a number of times over the first year.

Please follow all instructions carefully.

Note that the cornea has no blood supply,

so it heals slowly. If sutures need to be removed, the surgeon will typically remove them after one year.

Possible Complications

Corneal transplantation is broadly considered a safe procedure,

but as with any surgery, complications are possible.

The body's immune system may attack the donor cornea —

this is known as graft rejection.

In most cases it can be treated with drops or medication,

but it requires patient vigilance: any noticeable drop in vision

should prompt an immediate appointment, since rejection in its early stages is much easier to reverse.

In some cases, a repeat transplant may be needed —

often only the back layer is replaced this time, using DSAEK

or DMEK, which carry a much lower rejection rate.

Other possible complications include:

- Infection

- Bleeding

- Elevated intraocular pressure (glaucoma)

- Lens opacity (cataract)

- Corneal swelling

Outcomes and Success Rates of Corneal Transplant

Most patients who undergo corneal transplantation regain functional vision relatively quickly,

and corneal transplant has the highest success rate of any organ transplant in medicine.

Success rates exceed 90%, although every case is different.

It may take several weeks — or even up to a year — for vision to fully stabilize.

You may need updated glasses or contact lenses

that include astigmatism correction, since a transplanted cornea is rarely perfectly spherical

and may produce some residual astigmatism.

After the first year, you should follow up with Dr. Shaarawy once or twice a year.

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