WHAT IS ORTHOKERATOLOGY?
Orthokeratology, or Ortho-K for short, is a non-surgical and reversible procedure in which custom-designed contact lenses are used to gently reshape the cornea (front surface) of your eye. It uses the forces of the eyelid and tear fluid beneath the lens to reshape the top layers of the cornea. It is also known as Corneal Reshaping Technology (CRT) and lenses are worn while sleeping and removed in the morning, giving you clear vision during the day without the aid of glasses or contact lenses. Orthokeratology may sound dramatic, but it is quite simple. ‘Ortho’ means to ‘correct’. Orthodontics correct teeth. Orthokeratology corrects the refractive error by reshaping the cornea.
For treatment of myopia, the lens produces a flatter central cornea, correcting near-sightedness by decreasing the power of the eye.
Using a Medmont corneal topography map of your cornea, (taken by our optometrist, Dr. Pezeshk), specialized software is used to design a computerised simulation of your custom made lens, without the need for time consuming and uncomfortable in office trial fitting.
Improvements in vision can usually be seen the next day, with the procedure stabilising after a week. With high myopia over -6.00D, astigmatism and hyperopia the process can take two to four weeks to achieve full correction. Ortho-K does not permanently change the shape of the eye. Your eyes’ shape will revert back to their original state within one to four weeks if you stop wearing the lenses.
HOW NEW IS ORTHO-K?
Reshaping the cornea using standard rigid contact lenses was first reported in 1962 at the International Society of Contact Lens Specialists conference in Chicago, by George Jessen who described his “orthofocus” procedure. Unfortunately, this process took too long, and results were unpredictable. With technological advancements in lens materials and manufacturing, the modern reverse geometry orthokeratology lens was introduced in the late 1980’s. In 1994, the United States FDA granted the first ever daily wear approval for Ortho-K and in June 2002, the FDA granted approval for overnight wear Ortho-K.
HOW SAFE IS ORTHOKERATOLOGY?
Any contact lens has the potential to cause an infection in your eyes. Research shows the rate of infection using Ortho-K lenses is less than half compared to overnight wear of extended wear soft contact lenses.
Using correct hygiene and lens care regimes as well as replacing the lenses every one to two years significantly reduces the risk of Ortho-K related complications.
A poorly fitted Ortho-K lens can result in corneal staining, which comprises the outer layer of the cornea, and increases the risk for
infection. Rather than fit Ortho-K lenses through trial and error using a diagnostic lens from a trial case, our optometrist, Dr. Pezeshk uses a specialized tool called a corneal topographer to calculate and custom design the fit of each Ortho-K lens to the topographical shape of the cornea.
