A new method of treating cataracts is now being tested on a limited number of human patients, following successful trials on animals.
A collaborative effort between Ameican and Chinese researchers from the University of California-San Diego (UCSD), Sun Yat-sen University in Guangzhou and Sichuan University have been using stem cells to regrow parts of the eye that have been affected by cataracts.
The results of the study have been published in the journal Nature. The human tests involved just 12 patients, all of whom were babies born with cataracts. The restults show that all 12 had improved vision, and the surgical processes involved led to far fewer complications than traditional treatment methods.
Cataracts cause the eye's cornea to become cloudy, which then prohibits light from passing through the eye and onto the retina, where the image is sent to the brain. Ultimately, cataracts make clear vision impossible without surgical treatment.
In the past, lens have been transplanted from donor eyes, or have been grown in a lab using the patient's own stem cells.
In the new experimental process, however, stem cells were used to allow the eye to regrow new lenses on its own. By regenerating it's own tissue, the risk for both infection and tissue rejection are both significantly lowered.
Humans continue to produce endogenous stem cells throughout their entire life, however, the rate that these cells are created drops steadily as a person ages. This means that while cataracts typically effect the elderly far more often than younger people, they may be less viable candidates for this type of treatment.
Further testing is required before this type of surgery becomes more widely available.