Orthokeratology (ortho-k) is a non-surgical treatment using specially designed high oxygen permeable retainer lenses to gently reshape the cornea (the front surface of your eye); these special retainers are worn only while you sleep and provide clear, natural vision when the retainers are removed upon waking. The principle is similar to a dental retainer used by an orthodontist to straighten misaligned teeth. The vision retainers are similar to contact lenses and are only worn while you sleep. This method can be used to treat myopia (nearsightedness) and astigmatism as an alternative to eyeglasses, refractive surgery, or daytime contact lenses. 

Ortho-k may sometimes be referred to as corneal refractive therapy (CRT), overnight vision correction, Gentle Vision Shaping System, or Vision Shaping Technology. 

Ortho-k is appropriate for all ages, from elementary school children to active seniors. Candidacy will depend on your prescription, tear secretion, corneal shape, rigidity of the cornea, and overall eye health. Ortho-k works best on mild to moderate amounts of nearsightedness and astigmatism. More severe cases can still have their vision improved, but may still need some vision correction. 

Our specially trained Oakville Eye Care optometrists will perform a complete vision assessment, eye health exam, and corneal topography scan to determine if orthokeratology will be a suitable treatment. Dr. Yeung has extensive experience being in Ortho-K lenses for over a decade. We will use our state-of-the-art Medmont E300 Topographer (considered the GOLD standard in our industry) and specialized computer software to determine if you are a good candidate.  

Orthokeratology is safe and we utilize only FDA approved materials. However, wearing ortho-k retainer lenses does carry the same risk as wearing soft disposable daytime contact lenses. There is a small risk of eye infection when any contact lens is worn, whether they be soft disposable or gas permeable contact lenses and whether they be worn during the day or overnight. 

It is very important for all contact lens wearers to take proper care of their lenses as instructed by their doctor, improper care can increase the chance of adverse reactions.

Rigid gas permeable contact lenses similar to those used in orthokeratology has been shown to slow the rate of progression of nearsighted children compared to children in eyeglasses. According to recent studies, orthokeratology has shown between 50-90% success rate in controlling near-sightedness in children.