Researchers develop minimally invasive surgical technique for treating cataract

A team of U.S. and Chinese researchers have developed a new surgery procedure to remove congenital cataracts in infants, permitting remaining stem cells to regrow functional lenses, according to a study published Wednesday in the journal Nature.

The treatment, developed by researchers at the University of California, San Diego School of Medicine and Shiley Eye Institute, with colleagues in China, has been tested in animals and in a small human clinical trial.

It produced much fewer surgical complications than the current standard-of-care and resulted in regenerated lenses with superior visual function in all 12 of the pediatric cataract patients who received the new surgery, says the study.

Congenital cataracts, lens clouding occurring at birth or shortly thereafter, is a significant cause of blindness in children. Current treatment is similar to adults -- lens replacement surgery -- though treatment is limited by the age of the patient and related complications. Most pediatric patients still require corrective eyewear after cataract surgery.

Current cataract surgeries largely remove lens epithelial stem cells or LECs with the lens. The lingering cells generate disorganized regrowth in infants and no useful vision.

After confirming the regenerative potential of LECs in animal models, the researchers developed a novel minimally invasive surgery method that preserves the integrity of the lens capsule, which is a membrane that helps give the lens its required shape to function, and way to stimulate LECs to grow and form a new lens with vision.

"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," said Kang Zhang from the University of California, San Diego, who is one of the authors of the study.

As the body's own cells are used, the therapy wouldn't have the risk of rejection or tumors, according to Zhang.

In subsequent tests in animals with cataracts and in a small human trial, researchers found the new surgical technique allowed pre-existing LECs to regenerate functional lenses.

"The success of this work represents a major paradigm shift in how new human tissue or organ can be regenerated and human disease can be treated, and could have broad and profound impact on therapies by utilizing the regenerative power of our own cells," said Zhang.

But the new surgical technique still needs to be refined and further tested in larger human clinical trials before it can be applied in future treatments, added Zhang. Endit