Cornea transplant, also called keratoplasty, is a surgical procedure in which the central portion of a patient’s cornea is replaced with tissue from a donor cornea. The cornea, the clear tissue at the front of the eye, works with the lens inside the eye to refract incoming light. For most people, the cornea helps provide good vision throughout life, though some people may need spectacles, contact lenses, or refractive surgery in order to sharpen that vision. However, physical injury to the cornea, certain infectious diseases, and degenerative conditions such as keratoconus can leave the cornea scarred, damaged, or less than perfectly clear. In such cases, a cornea transplant becomes necessary in order to restore good vision. Cornea transplantation is the most commonly performed tissue transplant in the world.
There are several types of cornea transplant available today, suitable for treating a variety of cornea conditions. The board-certified cornea specialists at Hoopes Vision are experienced at all of these variations, and can recommend the type of transplant that is likely to provide the best result for each individual patient.
Penetrating Keratoplasty (PK) is the oldest type of cornea transplant procedure, and is still the one most commonly performed today. In a PK procedure, the patient’s damaged or diseased central cornea is removed by the surgeon. The surgeon then puts a similarly-sized piece of a donor cornea in its place, securing it with sutures. At the hands of a trained, experienced surgeon, PK is a safe, predictable procedure with a high probability of restoring good vision.
Descemet’s Stripping Automated Endothelial Keratoplasty
Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) is a relatively new procedure, part of a family of newer transplant procedures known collectively as partial-thickness transplants. Whereas in PK all five layers of the cornea are removed and replaced – a full-thickness transplant – in DSAEK only the innermost layer, the endothelial layer, is replaced. Compared to PK, DSAEK requires fewer sutures and has a faster recovery time and lower incidence of tissue rejection. DSAEK can be a good option for patients with conditions such as Fuch’s Dystrophy, which affect only the endothelial layer.
Deep Anterior Lamellar Keratoplasty
Deep Anterior Lamellar Keratoplasty (DALK) is another partial-thickness transplant procedure. In a DALK surgery, the endothelial layer is left intact, and only the outer layers of the cornea are replaced with donor tissue. Compared to PK, DALK can give better postoperative vision, and the risk of graft rejection is nearly zero. DALK can be a good option for certain patients with keratoconus. The newest development in this procedure is the advent of laser-assisted transplants, known as Femtosecond Laser Enhanced Deep Anterior Lamellar Keratoplasty (FLEDALK). In a FLEDALK procedure, a computer-guided laser is used to prepare the patient’s graft site as well as to shape the donor tissue, leading to a better fit and stronger graft.
HOW LONG WILL THE SURGERY TAKE ?
Patients are typically in the operating room for about an hour, and in the surgery center for a total of about two hours, on the day of surgery.
After surgery, it is normal to feel some stinging and discomfort, as well as the sensation of a foreign body in the eye. This discomfort is usually managed with over-the-counter acetaminophen. Severe pain after surgery is not normal.
Vision is usually blurry after surgery. It improves over time, but can fluctuate as the graft heals. Therefore, the surgeon will monitor your vision for stability, and may wait anywhere from three months to a year before giving you an updated eyeglass or contact lens prescription.
It depends on the nature of you work, as well as your recovery. Patients with indoor office jobs and good vision in the non-operative eye can often return to work within a few days. Patients who work in dusty environments or whose work requires heavy lifting may be instructed to take several weeks off.
Op.Dr Ahmet Umay