From the Telegraph: "Russell Turnbull, 38, lost most of the vision in his right eye when he had ammonia sprayed into it as he tried to break up a fight on a late night bus journey home. The attack, which badly burned and scarred his cornea, left him with permanent blurred sight and pain whenever he blinked. Now however his sight has been almost fully restored thanks to a new technique where doctors regrow the outside membrane of his cornea from stem cells taken from his healthy eye. The new operation involves cutting away a millimetre squared section of his left eye complete with stem cells and growing it to 400 times that size in the laboratory. The new outer skin of the eye is then stitched onto the badly damaged cornea in place of the damaged membrane. The technique [has] been used on eight patients and for most of them including Mr Turnbull it has almost completely restored their vision."