Stem cells may be a key in finding the next treatment for cataracts, according to a new study. The condition, which is due to the eye's lens becoming less clear or cloudy, is the leading cause of blindness worldwide and cataract surgery is one of the most common operations across the globe.
But there may be a better and less invasive way to treat cataracts, according to a study published today in the journal Nature.
Scientists were able to modify the conventional cataract surgery to remove damaged lenses from 12 infants, but not remove too much of their natural lens epithelial stem cells so that these cells could regenerate the lens.
They studied 12 infants up to 2 years old and found they generally had less inflammation and better outcomes than patients who underwent the conventional surgery, where the damaged lens is removed. In conventional cataract surgery, the lens is either replaced with another lens or the child is given glasses or contacts, and naturally occurring stem cells are deliberately not allowed to regenerate the eye lens.
In all of the studied children, the lens that regenerated was back to a normal thickness approximately eight months after the surgery, the study found. Additionally, because the incision was in a slightly different place, there was less chance that it would impact the child's sight. The procedure resulted in less inflammation and complications compared to the standard cataract surgeries.
“An ultimate goal of stem cell research is to turn on the regenerative potential of one’s own stem cells for tissue and organ repair and disease therapy,” Dr. Kang Zhang, lead author of the study and chief of Ophthalmic Genetics and founding director of the Institute for Genomic Medicine, said in a statement today.
The new procedure worked by relying on the body's natural lens epithelial stem cells, which generate replacement cells throughout a person's life. As a person ages, the cells decline, which means this procedure may not work for older patients.
“We believe that our new approach will result in a paradigm shift in cataract surgery and may offer patients a safer and better treatment option in the future," said Zhang, who is also co-director of Biomaterials and Tissue Engineering at the Institute of Engineering in Medicine at UC San Diego School of Medicine.
Dr. Faruk Orge, a pediatric ophthalmologist at University Hospitals Case Medical Center, said the study was very exciting although more research was needed to see if older patients could benefit as well.
"This is an amazing step and breakthrough for clinicians," Orge told ABC News today. "It has the potential for being the next step," in treatment.
Orge, who was not involved in the study, said doctors had known about the potential for regeneration for some time, but that it was not clear that the lens would regenerate clearly.
"Lens material is like a butterfly's wing, if something irritates it, it changes its nature," Orge said. "It’s like looking through a very dirty glass or a very milky glass."
While the results are exciting, Orge pointed out the small study size means more work needs to be done to ensure the procedure's safety and effectiveness in a wider range of patients.
"We’re talking about the most precious and vulnerable patients," Orge said of the infant patients. "We have to continue the research ... and make sure it’s good for the patient."