March 19 (UPI) -- Researchers in California have developed a retinal patch with stem cells to improve the vision of people with age-related macular degeneration.
In a clinical trial, researchers at the University of California Santa Barbara implanted the stem cell-derived ocular cells in two patients over the course of 12 months, publishing the results of the study Monday in the journal in Nature Biotechnology.
Macular degeneration, which affects the central, or reading, vision while leaving the surrounding vision normal, usually affects people over 50 years of age. The Centers for Disease Control and Prevention estimates that 1.8 million Americans aged 40 years and older have AMD, and it's the leading cause of permanent impairment of close-up vision among people aged 65 years and older.
People usually start with dry macular degeneration, which causes blurred or reduced central vision because of thinning of the macula. The dry condition, which accounts for 70 percent to 90 percent of all cases, can develop into the wet type, which is marked by abnormal blood vessels leaking fluid or blood into the region of the macula in the center of the retina.
Researchers hope the new procedure will help treat dry AMD before it progresses to the wet version.
In July 2015, 86-year-old Douglas Waters developed the disease and struggled to see things, even up close.
The researchers implanted a retinal eyepatch, which is composed of retinal pigment epithelium cells derived from stem cells, at Moorfields Eye Hospital, a National Health Service facility in Waters' hometown of London, England. They used microsurgical tools to implant the patch into the subretinal space of one eye.
After the surgery, he said he could read the newspaper with regular reading glasses and help his wife with gardening.
A woman in her early 60s with a severe form of wet AMD and declining vision also had a patch implanted, reporting the same kind of improvement -- she went from not being able to read at all to reading 60 to 80 words per minute with normal glasses.
"This study represents real progress in regenerative medicine and opens the door on new treatment options for people with age-related macular degeneration," Peter Coffey, a professor at UCSB's Neuroscience Research Institute and co-director of the campus's Center for Stem Cell Biology & Engineering, said in a press release.
"We hope this will lead to an affordable 'off-the-shelf' therapy that could be made available to NHS patients within the next five years."