Cornea transplants, in which a diseased or damaged cornea is replaced with a donated one, are one of the most common transplant procedures performed. According to All About Vision, 47,000 transplants, also called cornea grafts, were performed in the United States in 2013. All told, a million have been performed worldwide since 1961.

As with all transplants, the procedure depends on the availability of a suitable donor. According to ZME Science, that situation may change in the next few years. Researchers at Newcastle University in the UK have successfully 3D-printed human corneas. The technique promises to lead to the creation of corneas on demand, which could bring sight to millions of people who are waiting for a donor before undergoing a transplant.

The 3D printing technique involves extracting some stem cells from a healthy cornea and combining them with alignate and a collagen to create a usable bio-ink. Ten minutes were sufficient to create the prototype cornea. The final step allows the cornea to grow in a culture dish.

More importantly, the technique will allow doctors to custom-make corneas that match a patient’s eyeball as well as his or her unique needs. The patient’s eye is scanned to get the correct dimensions and shape before the 3D printing procedure begins.

Several years of testing must pass before the technique will be made available in a clinical setting. However, the ability to 3D print a transplantable cornea is going to be a game changer for treating common causes of blindness. Candidates for the transplant procedure will no longer have to wait for a donor cornea to be made available and evaluated for suitability. A patient will have his or her new corneas custom made and then transplanted on demand. The 3D printing technique could restore sight to millions of people whose vision has been impaired because of injury or disease.