What is Orthokeratology?
Orthokeratology (or Ortho-K) is the programmed use of specially designed contact lenses to improve unaided vision by reshaping the cornea (front surface of the eye). Myopic (short-sight) and astigmatic (irregular surface) errors of the eye may be reduced or eliminated. Ortho-K lenses are worn while sleeping and removed on waking. They have a unique design, which generates pressure in the thin layer of tears under the lens. This gentle tear pressure, rather than the lens itself, is responsible for the subtle change in corneal shape. This alteration in corneal shape is associated with improvement in uncorrected vision. Ortho-K lenses are highly oxygen permeable so treatment can proceed during sleep without the problems caused by a lack of oxygen to the cornea.
