By Susan J. White
NorthShore University HealthSystem
Our corneas are the only part of the body that are, when healthy, crystal clear. On the inside of the cornea there is a single layer of cells -endothelial cells- that are unique in that they don’t reproduce. Over time, and following trauma, infections, surgery or certain inherited disorders these cells can fail. When endothelial cells are damaged, the cornea is no longer clear and vision is compromised.
As the population ages, the need for corneal transplants is becoming more common, and thanks to advances in technology, the transplant procedure has become far less traumatic, according to Marian Macsai, MD, a NorthShore University HealthSystem (NorthShore) ophthalmologist with expertise in cornea and refractive surgery. Dr. Macsai, who is also Chair of the Eye Bank Association of America, was one of the first physicians in the Chicago area to perform a partial thickness, or Descemet’s Stripping Endothelial Keratoplasty (DSEK), corneal transplant.
A traditional corneal transplant replaces the entire full thickness cornea with a cornea from a donor, and generally takes up to a year or more for a patient’s vision to be restored, leaving them with a larger wound 24 stitches, and potential weak spot in the eye, vulnerable to further damage from a fall or other trauma.
In the advanced DSEK procedure, a much smaller incision is used and only a very thin layer (approximately 100 microns) of donor cornea is inserted into the eye. After the new endothelial cells are unfolded in the eye, an air bubble is placed in the front part of the eye to push the new cells up against the dome-shaped cornea, explains Dr. Macsai.
Only one or two stitches is needed in the eye, and after laying still in the recovery room for an hour, patients are sent home with a patch on their eye and instructions to take it easy for the first day, Dr. Macsai says. More than 95 percent of the time, the new donor cells are in place the next day and normal vision typically returns in four to 12 weeks, as opposed to the year-plus following full thickness corneal replacement. The smaller incision also helps alleviate the potential for a weak spot susceptible to future trauma, she says.
“Preliminary studies show that the risk of rejection is lower in DSEK than in full-thickness transplant,” Dr. Macsai adds. “It is so exciting in our field right now to be able to offer patients this improved technology that gives them increased safety and faster recovery with exceptional results.”
Another major advantage of the DSEK procedure is the fact that it allows a far larger segment of the population to donate their corneas, including older donors and some who have had LASIK or even a scar on their cornea, as such a small section of endothelial cells is needed for the transplant.
Donating corneas is a far simpler process than donating other organs, as the donor does not need to be on life support. Dr. Macsai and her colleagues encourage everyone who is willing to donate their corneas to inform their families of their desire to donate. Approximately 43,000 corneas are harvested in the United States for transplants every year, and there are waiting lists for those who need donor corneas.
Exciting research initiatives are underway and the future is promising for even more advances in the area of restoring vision for those with damaged corneas, Dr. Macsai suggests.
