DSAEK and DMEK
Descemet’s Stripping Automated Endothelial Keratoplasty (DSAEK) and Descemet’s membrane endothelial keratoplasty (DMEK) are newer cornea transplant techniques that replace only the damaged cell layer instead of replacing the entire thickness of the cornea. With this technique cornea heals much faster and stronger and the patient’s visual recovery is better. Because this technique leaves a smoother interface and significantly improves the visual results, it has become a preferred method for treatment for Fuchs’ Dystrophy and pseudophakic bullous keratopathy.
The DSEK and DMEK procedures can overcome many of these problems associated with a standard corneal transplant. With a DSEK/DMEK procedure only the abnormal inner lining of the cornea is removed. A thin, circular disc is then removed from the inner lining of a donor cornea. This is folded and place inside of the eye where an air bubble pushes it in place until it heals in an appropriate position. No sutures are required and the structure of the cornea remains intact, leading to a faster visual recovery and less astigmatism.
Advantages of DSAEK and DMEK compared to standard corneal transplantation
- The eye surface is kept intact, thus remaining more resistant to injury and infection
- There is minimal change in refraction because only the endothelial layer (~5% of the cornea) is replaced
- Suture-related problems are significantly reduced/can be eliminated
- Visual recovery is significantly faster and better
What is the difference between DSAEK and DMEK?
DMEK is very similar to DSAEK, except that the donor tissue implanted does not include any stromal tissue. It is a pure replacement of endothelium. This tends to give better visual results and a quicker recovery; however, donor disc dislocations and failures are more common. Dr. Thomas will fully discuss your options based on your individual needs.
PKP
Penetrating Keratoplasty (PKP) involves replacing an eye’s scarred, diseased or damaged cornea with clear corneal donor tissue. This procedure can improve visual acuity as it is replacing the cloudy cornea with clear donor tissue. PKP is suitable for those with for corneal decomposition, corneal dystrophies (other than keratoconus) including Fuch’s Dystrophy, and corneal trauma/corneal scarring. The donor cornea is prepared to create the corneal “button.” The corneal button will become the transplanted cornea. The diseased, or scarred, cornea is then removed, creating a “bed” for the transplant cornea. Finally, the donor cornea is gently sewn into place with ultra-fine sutures (approx. one-third the thickness of human hair, or less). Stitches are typically removed at one year.
Postoperatively, patients should expect very gradual recovery of vision. In fact, the best vision may not be obtained for six to 12 months or more following surgery, even though vision may be improved from the first day after surgery in some cases.
