Artificial sight

An engineering team at the University of Dundee has just secured funding to work with European colleagues on the construction of artificial corneas which will allow all cornea replacements to go ahead without the patient having to wait for a donor.

The Euro 2.4m project will help people who suffer from a number of diseases requiring corneal grafting including keratoconus – a thinning of the cornea. Instead of relying on donor corneas from an eye bank, the new technology invented by biochemists, tissue engineers and structural engineers will allow the European team to grow the cornea from human stem cells in a test tube.

The team of structural engineers at the University of Dundee who will be testing the mechanical properties of the new cornea – its elasticity, resistance and strength – are the only UK team to be part of the European research project into this revolutionary cornea. The other teams are based in Sweden, Turkey, Denmark and France and Italy where surgeons will be testing the new corneas.

Dr Ahmed El-Shiek and Dr Tim Newson will be using computer imaging to create an eye and test its mechanical properties to judge how flexible, and strong the new artificial cornea will have to be. Dr El-Shiek explains: “The cornea in the eye holds all the components of the eye in place. We have to make sure that our artificial cornea is strong enough to do this but flexible enough to be as resistant to force as a real cornea. We apply pressure waves to the computer generated model and monitor the effect on the eye.”

There is currently a need to develop new forms of corneal replacements as alternatives to the use of donor corneas because there is a world-wide shortage of donors, an increasing risk of transmittable diseases and widespread use of corrective surgery which renders corneas unsuitable for grafting and the limitations of currently available synthetic polymer-based artificial corneas.

As well as their contribution to the cornea project, Ahmed and Tim are looking at the other possibilities of the virtual eye they have created. The amount of the cornea skimmed off during laser surgery is currently judged on what has worked before for other people. Ahmed and Tim are going to use their model to predict how each eye will react to laser surgery improving the effectiveness of laser surgery and optimising the process.