A new, minimally invasive procedure appears to be effective for many patients with Fuchs endothelial dystrophy, a common eye disease, without the potential side effects and cost of a cornea transplant.
In a proof-of-concept study, published in the journal Cornea, researchers led by Kathryn Colby, the Louis Block Professor and chairman of Ophthalmology and Visual Science, showed that removing a few square millimeters of a single layer of cells on the inside of the cornea allowed rejuvenation of the surrounding tissue, without the need for a corneal transplant. This simple procedure restored clear vision to three out of four patients suffering from FED, the most frequent cause for corneal transplantation in the United States.
Over the past two years while at Harvard Medical School, Colby performed the new procedure, known as Descemet stripping, on 11 patients aged 51 to 91. Two patients had the procedure in both eyes, one at a time.
When assessed six months after the operation, ten of the treated eyes (77 percent) had clear corneas and eight had 20/20 vision or better (two patients had retinal disease that limited their final vision). The other three eyes did not respond and required a standard cornea transplant.
“It’s too soon to call this a cure,” Colby said. “We performed the first operation just over two years ago. But when it works, it’s a wonderful thing. It’s quick, inexpensive, and it spares patients from having someone else’s cells in their eyes, which requires local immunosuppression.”
The first patient to undergo Descemet stripping, 69-year-old Eric Thorp of the Boston area, was pleased. “It’s quite a breakthrough,” he said. His vision, now 20/20 in that eye, “is equivalent to what I had as a boy,” he said. “Amazing.”
“It’s kind of an honor to have been the first,” he added. “It was worth doing.”
Descemet stripping involves removing a small patch of the corneal endothelium (the pumping cells that stop working in FED) attached to an underlying layer (the Descemet membrane). In patients with FED, water accumulates in the cornea, the clear front window of the eye, because of the dysfunction of the pumping cells, causing reduced vision, glare and haloes. If left untreated, the condition progresses to painful blindness.
Removal of the central dysfunctional cells enables healthier peripheral cells to migrate to the center of the cornea, where they reestablish pumping capacity and removal of fluid from the layers above. This gradually restores clear vision.
“Although Descemet stripping is a relatively simple procedure, its potential is revolutionary,” Colby said.