By Michael Hutton 

Contact lenses for sport  which use the long-established optical science or orthokeratology - or ortho-k for short - have enabled Wasps RUFC star Jo McGilchrist to secure selection for England's Rugby World Cup squad for the forthcoming tournament in France which starts on August 1st. The ortho-k lenses are unique because they are only worn while sleeping so that the wearer enjoys perfect natural vision all day long after removing the lenses each morning.

Jo is short-sighted and previously wore conventional daytime contacts which can be a big problem for a rugby player: "Playing as a forward in a contact sport I frequently lost or dislodged my contact lenses during matches and would have to leave the pitch to put in replacements. I would also have difficulty trying to put them back in when they fell out on the pitch using muddy hands." For many sports participants, this is a familiar problem.

After switching to overnight ortho-k contact lenses for sport , Jo was delighted to find that she had perfect lens-free daytime vision: "Now I am able to train and play without any worries about losing lenses and I wore the ortho-k lenses overnight throughout the last World Cup tournament where we lost to New Zealand in the Final". After some extended injury problems over the past couple of seasons, Jo is now fully fit and looking to see England go one better in the upcoming tournament.

Ortho-k contact lenses for sport  are custom-designed for each wearer and work by gently flattening the surface of the cornea under the mild pressure of closed eyelids during sleep. This flattening ensures that, once the lenses are removed each morning, light entering the eyes focuses directly on the retina rather than in front of it which is when distant objects appear blurred. The effect lasts for over 24 hours so perfect vision is maintained until the lenses are reinserted at night.