Orthokeratology
Orthokeratology has been defined as the reduction, modification or elimination of a visual defect by the programmed application of contact lenses. From a patient’s point of view it can be described as a safe, reversible system of non-surgical vision correction that requires semi-permanent wear of a contact lens. Based on experience gained and observations noted from the days of hard contact lens fitting in the 1950’s and 60’s, a small degree of corneal flattening and consequently reduction in myopia was possible with appropriately fitted lenses. |
With the development of completely new lens designs made from highly oxygen permeable materials, combined with the availability of computer-assisted videokeratoscopes to accurately measure the corneal contours, interest in corneal moulding as a means of optical correction was revived in the 1980’s.
Currently the most popular lens design is the reverse geometry lens, which induces faster and increased myopia reduction when worn on an overnight basis. A reduction in prescription of 70% is possible after the first nights wear and total correction is effected after 1month. Elimination of –4.50D of myopia and –1.50D of horizontal astigmatism is currently possible.
Interest in the procedure differs around the world. It has been widely carried out in the Netherlands for the past 10 years, where over 10,000 Patients have been successfully fitted. Similarly in the Far East it has been used as an alternative visual correction for young people, and has been found to have beneficial effects in reducing the rate of development of their short sightedness. Further investigation needs to be carried out to determine if these effects are long lasting on ceasing lens wear. |
Future developments will include lens designs that eliminate higher degrees of myopia, hyperopia (long sightedness) and presbyopia (the normal reading deterioration with age).
Our Masons Avenue branch has treated patients using Orthokeratology since 2005.