Corneal transplantation has come a long way. Treating corneal disease is no longer the obstacle it once was, and even the historic shortage of donor tissue matters less than it did — partial transplant techniques now allow a single donor cornea to benefit more than one patient. Instead of replacing the full thickness of the cornea, the surgeon replaces only the damaged layer. This article explains what a partial corneal transplant is, which techniques exist, and when each one is used.
First, What Is Corneal Transplantation?
A quick refresher from earlier articles: corneal transplantation, also known as keratoplasty, is a surgical procedure in which a damaged cornea is removed and replaced with healthy donor tissue from someone who chose to donate their corneas after death.
💙 A note from Dr. Ahmed Shaarawy's team
In the spirit of sharing positive energy with patients considering corneal transplantation, here is a real story from someone who walked the same path you're considering today. We share it so you know there is a solution — and that the procedure is no longer as difficult as it once was, thanks to the advanced techniques Dr. Ahmed Shaarawy uses.
📅 Book a consultation with Dr. Ahmed Shaarawy
What Are the Types of Corneal Transplant?
Corneal transplant surgery used to be far more drastic. The full cornea had to be replaced whether the whole cornea was diseased or only certain layers — which also fed a chronic shortage of donor tissue. That picture has changed, as you'll see below.
Corneal transplants are broadly divided into two categories: full-thickness (penetrating) and partial-thickness (lamellar).
1. Penetrating Keratoplasty (Full-Thickness Transplant)
Also called a full-thickness corneal transplant, this procedure is abbreviated PK (PKP).
In PKP every layer of the cornea is replaced. Using either a manual trephine or a femtosecond laser, the surgeon removes a small circular section of the cornea and replaces it with a matching-thickness disc of donor tissue. For decades this was the most common type of corneal transplant.
2. Partial Corneal Transplant (Lamellar Keratoplasty)
There are two main categories of partial corneal transplant.
Type 1: Anterior Lamellar Keratoplasty (ALK)
Here the diseased tissue from the front layers of the cornea (the epithelium and stroma) is removed, while the back endothelial layer stays untouched. Two main techniques exist.
The first is Superficial Anterior Lamellar Keratoplasty (SALK), in which only the most superficial layer of the cornea is replaced — the stroma and endothelium stay in place.
The second is Deep Anterior Lamellar Keratoplasty (DALK), used when the corneal damage extends into deeper layers.
Which of the two is right for you depends entirely on your specific case.
Lamellar keratoplasty is gentler on the eye than penetrating keratoplasty. The patient generally faces a lower risk of graft rejection and fewer complications. Recovery is also more comfortable, and visual rehabilitation is faster.
Type 2: Endothelial Keratoplasty (EK)
Most patients who need a corneal transplant actually have damage centred on the deepest layer of the cornea — the endothelium. This category of transplant divides into two techniques.
Type 2a: Descemet's Stripping Endothelial Keratoplasty (DSEK / DSAEK)
DSAEK is the most common form of endothelial keratoplasty. Healthy donor tissue replaces about one-third of the corneal thickness: the diseased endothelium is removed along with a layer of Descemet's membrane (the tissue that supports the corneal endothelium), while the outer corneal tissue remains intact.
The second technique is Descemet's Membrane Endothelial Keratoplasty (DMEK). Here an even thinner layer of donor tissue is used — just the endothelium and Descemet's membrane — making DMEK one of the most precise corneal transplant techniques available.
Again, the right approach comes down to the patient's specific case.
The Right Surgeon for DMEK
Dr. Ahmed Shaarawy is among the most experienced surgeons in Egypt for DMEK, having been the first to perform the procedure locally. He is a Lecturer and Consultant of Cornea and Refractive Surgery at the Research Institute of Ophthalmology, with a PhD and a fellowship in cornea from Legacy Devers Eye Institute in Oregon, USA. There he trained under leading American cornea surgeons and was the first to perform DMEK in Egypt using the S-Stamp technique.
He has helped train many other surgeons in this technique and has presented on it at conferences across the United States and the Arab region. With a long record of successful surgeries and consistent adoption of the latest cornea techniques, Dr. Ahmed Shaarawy is regarded as one of Egypt's leading ophthalmologists.
Advantages of Partial Corneal Transplant
Why go partial rather than full-thickness? Several reasons:
- Fewer complications
- Lower risk of induced astigmatism
- A lower rate of graft rejection compared to full-thickness transplant
- Faster recovery
- One donor cornea can benefit multiple recipients
Risks of Corneal Transplantation
One thing every patient should understand: the donor cornea is foreign tissue, and the body may attempt to reject it. Rejection or related problems can show up as:
- Eye infection
- Corneal inflammation or ulceration
- Cataract
- Elevated intraocular pressure
Caught early, most of these complications can be managed effectively.
Your eyes are your most valuable sense. If you need a corneal transplant, don't put off taking that step — clear vision is what lets you enjoy the world around you.
For more information about corneal transplantation, you can read this article.
