'If you are a short-sighted sportsman or woman, work in a dusty workplace or suffer from dry eyes, wearing glasses or contact lenses during the day may not be an option. The Ortho K system – contact lenses that correct short-sightedness while you sleep – could offer a solution. Wearing the tailor-made gas-permeable lenses overnight reshapes the cornea (the dome shaped window covering the front of the eye) to its correct position, giving the wearer 20/20 vision upon waking. The sight correction generally lasts for the entire day, and sometimes longer: some wearers find they may only need to wear the lenses every other night. Swimmers, rejoice: you can wear them in the pool, too. Although the lenses don’t cure short sight, some studies have indicated that using them may slow down the progression of myopia. The technology has been around since the 1960s, but has only recently become affordable.

Optometrist Charles Babumba, of City Eyes in the City of London, is prescribing Ortho K lenses to many of his patients, including his 13-year-old daughter, and monitoring the results. “The lenses are not appropriate for everybody,” he says. “They are not suitable for people with diabetes, high blood pressure or very high prescriptions (over -6), or astigmatism. They only work when the wearer is asleep and must be worn for at least six hours, so some people’s lifestyles might rule them out.”

Guardian Health Section