DSAEK: Cornea Transplants Revolutionized
DSAEK: Cornea Transplants Revolutionized
Dr. Cavanaugh has extensive experience performing DSAEK transplants
Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) is revolutionizing corneal transplantation. Until recently, corneal disease patients had very few treatment choices to regain clear vision. The most likely option was a full thickness corneal transplant – a complicated procedure that surgically replaces the entire cornea from front to back with a donor cornea.
Several diseases can affect the cornea, or clear covering of the eye, such as Fuchs Dystrophy, which causes cloudy vision, and Keratoconus, which creates visual distortion through high and irregular astigmatism. Other surgical options can correct many conditions, but in some cases, a corneal transplant is needed. DSAEK is a non-invasive and advanced technique that uses a small, suture-less incision to remove just the back layer of the cornea. This provides great results with a much faster recovery time than in traditional cornea transplant surgery.
How is DSAEK Different from Full Transplants?
DSAEK involves only replacing some of the posterior or inner layers of the cornea as compared to the standard corneal transplantation (replacement of all layers). While both the standard corneal transplants and anterior lamellar corneal transplants have been done for many years, surgery that replaces the posterior layers of the cornea only is relatively new. Furthermore, DSAEK is only for selected patients with Fuch’s dystrophy or other disorders involving the endothelial or inner layer only.
The DSAEK technique involves peeling off only the inner two layers of your cornea (ie Descemet’s Membrane and Endothelium). This allows replacement of the diseased posterior or inner layers of your cornea while preserving the remaining healthy cornea. In this way, patients retain 80% of their natural cornea and replace only the 20% that is diseased. The back surface of a donor cornea that has been pre-cut to the desired thickness and diameter is then folded and inserted through a small incision into the front fluid chamber of the eye. Once inside, the donor is carefully unfolded and floated up against the back of your cornea with an air bubble. You will be asked to recline or lay flat for about 48 hours in order for the air bubble to float to the top and hold the donor tightly against your cornea. With good compliance with this requirement, the donor cornea typically adheres to back of your cornea without the need for sutures.
Advantages & Disadvantages of DSAEK
The advantages of DSAEK surgery are:
- A smaller wound is made and fewer sutures are needed. Because of this, the eye heals faster and vision can return in 1-3 months instead of up to a year or more after a standard transplant.
- The eye is also less susceptible to injury and rupture after DSAEK compared to a standard corneal transplant.
- Surgical safety is much higher due to the small incision with greatly reduced risk of sight threatening complications. In some cases, sutures can lead to problems with infection or irritation to the eye after standard corneal transplantation. These problems should be greatly reduced with DSAEK.
- Stability in your eye’s prescription is much better. After DSAEK, one’s prescription for glasses may be similar to what it was prior to surgery but we often see a slight shift towards hyperopia or farsightedness. However, after standard corneal transplantation, patients can end up with large changes in the amount of astigmatism, nearsightedness or farsightedness compared to what they had before.
- DSAEK is much less invasive than full corneal transplants and thus has less potential complications.
- There is less risk of transplant rejection with DSAEK compared to standard corneal transplant.
Potential disadvantages of DSAEK:
- The most common problem that is encountered is that the donor cornea may dislocate or fail to attach to your own cornea. This would require additional surgery to correct; namely re-injection of another air bubble and/or possibly placement of sutures to hold the donor in place. As techniques have improved, this occurs in less than 10% of cases of DSAEK.
- In a very small number of cases, the donor cornea is incompatible or simply does not clear. If the donor fails to clear by 90 days after DSAEK, then a repeat DSAEK with a replacement donor is indicated.
- Rarely, haze, swelling or scarring occurs between the layers of the donated cornea and your own cornea which causes decreased vision and could necessitate a full thickness corneal transplantation to improve your vision.
- Finally, patients should ideally have had their cataracts removed prior to DSAEK but this can also done at the same time with DSAEK as a combined procedure. In the occasional younger patient who does not have a cataract, damage could occur during DSAEK surgery to the natural lens to either speed up or cause the development of a cataract (this can also occur during a standard corneal transplantation).
What to Expect on Your Surgery Day
Your outpatient surgery is performed at our state-of-the-art Ophthalmic Ambulatory Surgery Center, Deer Creek Surgery Center. The actual surgery takes 30 to 60 minutes, but plan on being at the center for a couple of hours. Surgery is typically done under local anesthetic. You will be given sedation medication and your eye will be completely numbed by a local block. During surgery, you will be unable see very much out of your eye (faint shadows or dim light may be seen). You will be awake but relaxed throughout the procedure.
Post-op Care of Your DSAEK
In the first few days, you may feel a foreign body sensation (a scratchy feeling) in the eye from the incision. Discomfort should go away within one week. Your vision will be blurry after surgery due to swelling and the air bubble used to keep your transplant in place. The swelling may last a few months while the cornea heals but the air bubble should dissolve within the first week. As the air bubble is absorbed and the tissue swelling decreases you should notice a gradual improvement in vision. The doctor will not recommend new glasses until he believes there is sufficient healing. Best vision generally takes three months but may take longer.
During the healing process, you will return to see the doctor frequently. Do not be concerned with visit frequency as transplants require close monitoring. At each visit, you will be given progress updates, medication and treatment instructions. The doctor and staff answer any questions or concerns you may have and schedule your next appointment.
Risks of DSAEK Surgery
Just as there may be risks and hazards in continuing your present condition without treatment, there are also risks and hazards related to the performance of your surgery. Your physician will review the particular risks relating to your health and the condition of your eye. The complete list of surgical risks is beyond the scope of this website and can be found in the Corneal Transplant consent form you will receive prior to surgery. Some of the potential risks of a DSAEK corneal transplant include, but are not limited to the following:
- Problems with healing
- Anesthesia complications
- Complications of surgery in general
- Risks associated with any eye surgery: Glaucoma, Cataract Formation
- Corneal transplant rejection
- Displacement of donor disc
- Failure of the donor tissue to clear
- Recurrence of pre-existing disease
- Induction of astigmatism