Sydney: They are worn only at night and removed in the morning, enabling normal vision by day without the need for spectacles or other contact lenses. Myopia or shortsightedness in children can be slowed or even halted by wearing these special contact lenses.
The finding suggests that orthokeratology (OK) lenses may help to reduce the growing incidence and severity of myopia throughout the world and especially in Asia.
"Our research has demonstrated conclusively that OK is effective, at least in the short term, in stopping the eye growth that causes myopia progression," said Helen Swarbrick, who heads the University of New South Wales Research in Orthokeratology (ROK) Group.
OK lenses have been in use for many years and are mainly used for correcting low to moderate myopia, or shortsightedness, according to a New South Wales University statement.
"After wearing the lens for an hour and then removing it, many short-sighted people can read a further two lines down on the standard optometrists` vision chart," says Swarbrick.
"The effect is dramatic. After a single night of OK lens wear, vision can improve by as much as six to seven lines."
Possibly genetic factors, dietary change and a surge in people doing more close work, viz reading, watching TV and looking at computer screens may explain why myopia has risen so dramatically.
The results were compelling: the study showed plainly that for most children wearing an OK lens inhibited the elongation of the eye, while the normal day lens did not.