What if you could temporarily correct your vision while you sleep? Orthokeratology (ortho-k) is a specially designed contact lens system that corrects myopia (shortsightedness) overnight. The effects last for up to two days, and the lenses can be worn again.
Ortho-k lenses are gas permeable contacts you wear overnight. Gas permeable, or rigid lenses are made of durable plastic that allows for more oxygen to reach the cornea than most soft contact lenses—making them “breathable” lenses. Ortho-k lenses work by gently reshaping the cornea, or front surface of the eye. In the morning, when the contacts are removed, the wearer can see clearly for up to 48 hours.
The lenses are prescribed for patients with mild to moderate myopia who are not eligible or don’t want LASIK surgery. They also assist in temporary correction of astigmatism, where the eye has difficulty focusing light for clear vision, and some cases of hyperopia (farsightedness). Ortho-k lenses have been proscribed to slow the progression of myopia in children, as well.
These overnight corneal reshaping contact lenses are prescribed and fitted by optometrists who measure the curvatures of a patient’s cornea to create a topographical map of the eye’s surface. Custom lenses are then ordered, or the optometrist can fit lenses that are in stock.
Patients report that the Ortho-k lenses are easy to adapt to, and comfortable for sleeping. Most have clear distance vision after only a day or two of overnight use. The effects of Ortho-k are cumulative, but also reversible, meaning people can stop using them and their eyes will gradually return to the previous corneal shape.
Ortho-k lenses are more expensive than regular contact lens systems, but about half the price of laser vision correction. There is no harm with long-term use and wearers can some using them and opt for laser correction (if deemed appropriate) within weeks or months of stopping Ortho-k.