Researchers Restore Vision by 'Growing' Eye Cells
To correct the problem, Ivan R. Schwab, MD, and R. Rivkah Isseroff, MD, took corneal stem cells that had been harvested either from the healthy remaining eye of the patient or from a living donor -- in Beebe's case, his sister. The donors volunteered to spare a small portion of cells from the outside edge of the cornea, right where it meets the white of the eye. The procedure requires only a small incision and does not appear to threaten the health of the donor's eye, researchers say. Schwab is professor of ophthalmology and Isseroff is professor of dermatology at the University of California at Davis.
As the researchers describe in the July issue of the journal Cornea, the cells were then grown in a lab dish. The new cornea is then transplanted onto the damaged cornea of the patient.
Ten of the 14 patients had successful results, defined as complete recovering of the corneal surface, stable or improved vision, and no recurrence of disease. One patient had vision improve from the ability to only count fingers before the transplant to 20/30 after; and a second went from counting fingers to 20/60. Both were considered success stories.
"The real exciting part of this is that ... other mucous membranes such as bladder, gut, lung, vagina, or rectum, probably, can be grown in the laboratory to be retransplanted into patients who have either traumatic or [disease] damage," says Schwab in an interview with WebMD.
In another study published in the July 12 issue of TheNew England Journal of Medicine, Ray Jui-Fang Tsai, MD and colleagues from Taiwan report on the use of a similar technique in six patients with severe corneal disease.
All six damaged eyes had complete recovering of the surface within two to four days, and by one month there was significant improvement of clarity of the cornea, the authors write. The average visual perception in five of the six eyes improved from 20/112 (severely impaired) before surgery to 20/45 (mildly impaired) after transplant. The sixth patient, who had total clouding of the cornea due to a chemical burn, had perception of 20/200 in the treated eye 15 months after the graft.