Corneal transplant techniques have come a long way. No one knows that better than Dr. David Rootman, a scientist, clinician investigator and ophthalmologist specializing in corneal surgery at the Donald K. Johnson Eye Institute and Sprott Department of Surgery at UHN. Dr. Rootman has performed corneal surgery for more than 30 years.
Yet, the cornea – the clear, domed window of the eye – is complicated.
The availability of human donor corneas is limited. And replacing an injured corneal component with an artificial one is not always successful.
"There are some [eye] conditions where it's like planting a tree in the middle of the desert and not giving it any water," says Dr. Rootman. "It's not going to survive."
Fortunately, advances in artificial cornea surgery, also called keratoprosthesis, are on the horizon. An Israeli medical device company is developing a new synthetic cornea that bio-integrates with the eye wall using nanofabric – a textile that is engineered with microscopic fibres that give it special characteristics.
Dr. Rootman was an integral part of the development of the artificial implant, providing guidance, resources and modification ideas for nearly four years. The device takes less than an hour to implant, doesn't have an expiry date or require special storage and could help reduce the need for donor corneas.
"I think that's [a big] part of the excitement about it," Dr. Rootman says. The implant is now going through an expedited FDA approval and has also been submitted to Health Canada for approval.
There is plenty of excitement around other aspects of cornea transplant too. Dr. Clara Chan, a cornea surgery specialist at the Donald K. Johnson Eye Institute and Sprott Department of Surgery, made history when she became the first to perform a deceased donor ocular limbal stem cell transplant in Ontario. (Limbal stem cells are essential to maintain the protective outer layer of the cornea and deficiencies can result in vision loss.) She also transplants stem cells from live donors to help patients with severe corneal scarring.
Although her work is innovative, Dr. Chan notes that not all patients may be good surgical candidates and recovery after such transplants is a lengthy process. Eyes that suffer from limbal stem cell deficiency often are at risk for other ocular complications. Still, she has seen limbal stem cell transplant patients experience life-altering outcomes. One man stopped needing his white cane after years of struggle. Another, a young mother born with limbal stem cell deficiency, can now look after herself and her children independently.
"We try our best to see what ways we can help them," says Dr. Chan.
