DMEK – The Next Method for Endothelial Transplantation
Corneal transplant procedures are continuing to become less invasive with quicker visual rehabilitation and safety. For years, the standard for corneal transplantation was a full-thickness transplant wherein the entire half-millimeter thickness of the patient’s central cornea was removed and replaced with a full-thickness donor cornea. This full-thickness procedure is very successful but requires a patient to maintain their stitches for a year. In addition, nearsightedness and astigmatism is usually induced with these types of transplants and the cornea is weakened and susceptible to trauma.
Many patients who require corneal transplants do so because of disease of the cells on the back surface of their cornea – termed endothelium. When patients have endothelial disease, transplanting the entire thickness of the cornea is really unnecessary unless there is scarring or degeneration of the other layers of the cornea. Several years ago, a new technique of corneal transplantation was developed in the Netherlands by Gerrit Melles, MD. With this new technique, named DSEK (Descemet’s Stripping Endothelial Keratoplasty), the diseased back surface of the cornea ( termed Descemet’s membrane ) was removed along with its associated diseased endothelium, and replaced with a thin donor tissue. DSEK allowed for the restoration or replacement of healthy endothelial cells which are responsible for keeping the cornea dehydrated and clear. The DSEK graft was very thin and included some corneal collagen tissue, Descemet’s membrane, and endothelium. The tissue could be folded and inserted through a small 5 mm incision and visual recovery was several weeks or months rather than several months to years for the full-thickness transplant procedure.
A variation of the DSEK procedure, called DMEK (Descemet’s Membrane Endothelial Keratoplasty) was also developed by the same surgeon in the Netherlands and offers even greater potential benefits than the DSEK procedure.
With DMEK, only Descemet’s membrane and the endothelium are transplanted, allowing for a smaller insertion incision, faster visual recovery (days to weeks), and less refractive changes following the procedure. The DMEK procedure is more challenging to perform due to the fragility of the transplanted graft but is slowly being recognized by corneal surgeons as the next evolutionary step in endothelial transplant methods. Eye banks are currently preparing for the future transition to this new technique; however, there will still be patients who are best served with either the DSEK procedure or the full-thickness corneal transplants, so the DMEK procedure will not totally replace the other transplant techniques. Patients with scars and keratoconus are not candidates for these ”back-surface” techniques since their pathology involves the front portion of the cornea.
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Commonly Asked Questions:
Are you one of the millions of men who take Flomax?
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Most cataracts develop as part of the aging process, from a change
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Cataracts can also occur at a younger age from any number of causes:
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