Regrowing a functional lens

Scientists have harnessed the body’s own stem cells to regrow lenses in a revolutionary new method to treat cataracts in children.

The method was trialled in 12 infants with congenital cataracts that developed during or soon after birth. It produced new lenses that gave the under-twos superior vision quality when compared to standard surgeries, according to the research published in the journal Nature this week.

This result came from a unique surgery that left behind the lens epithelial stem cells (LESCs), said lead researcher and University of California, San Diego, Institute of Genomic Medicine founder, Dr Kang Zhang.

In a typical cataract surgery, these LESCs are largely removed. The new method also retains the lens capsule membrane that acts as a scaffold for the new lens to grow on, Dr Zhang told OT.

“LESCs are present throughout one’s life and can be stimulated to grow by growth factors and a scaffold, or simply by injury,” he said.

The clear, regenerated, biconvex lenses were completely regrown in all patients three months after the surgery.

As well as giving the 12 infants better visual outcomes, the children also had fewer post-surgical complications and faster healing in comparison to a control group who received the standard surgery, Dr Zhang said.

He explained that the new method, which his team developed with Chinese scientists, is more complex than the lens removals done today. He added: “The learning curve will be steep … However this can be done entirely by a femtosecond laser cataract surgery machine.”

Dr Zhang emphasised: “These results are very exciting as they show LESCs can form an entirely new lens. We are looking to expand these findings into treatment of age-related cataracts to restore both distance and reading vision after cataract surgery in an older patient.”