Orthokeratology is an excellent alternative to correcting one’s vision without the use of glasses, surgery or eye exercises.

The fundamental principle of Orthokeratology is to change the shape of the front curvature of the eye (cornea) with a specially designed Rigid Gas Permeable Contact Lens. The effect is very similar to refractive eye surgery (PRK and LASIK) with the exception that with orthokeratology we do not cut into the tissue of the eye.

Through positive and negative (pushing and sucking) fluid forces under the lens we can manipulate the thickness of the epithelial cells (first seven layers of corneal cells). The interesting fact of these epithelial cells is that they were designed to move and change their thickness. This is necessary to help with the wound healing process of the cornea. All that we are doing with Orthokeratology is to control the precise movement and placement of these cells.

This is a histology picture taken courtesy of Dr. Jennifer Choo which demonstrates how the epithelial cells change their thickness under the Orthokeratology lens to create the vision correction.
Epithelial shape change due to orthokertology lens

As for long-term safety, modern Overnight Orthokeratology has now been around for over 13 years. I have personally been practicing Orthokeratology for more than 15 years with my wife being my first patient and have seen no serious eye infection in our practice due to Orthokeratology.
In this picture, you can see a topography scan showing her cornea after Orthokeratology.

Orthokeratology Bulls Eye Topography

If you review the safety/complication literature about Orthokeratology the severe cases were all due to infection of the eye and in most of these cases either the Orthokeratology practitioner was poorly trained, substandard materials were used or the patient was non-compliant to the required hygiene protocols (didn’t do as they were told by their eye care practitioner).

Research done by Australian and American corneal researcher institutes have all concluded that Orthokeratology holds no significantly higher risk to corneal health compared to regular contact lens wear and has a significantly lower risk profile when compared to refractive surgery, a fact that is further proven by the FDA (American Food and Drug Administration) approving Orthokeratology as a safe procedure for the correction of eye refractions in June 2002.

It is important to note that the effect of Orthokeratology is temporary. To maintain the vision correction, it is required to wear the retainer lens every night while you sleep. This is due to the epithelial cells being replaced in the cornea every ten days. The rejuvenation of the cornea presents a double edge sword for Orthokeratology.

On the one side it forces Orthokeratology to be a non-permanent correction method, but on the other hand, it allows the Orthokeratology process to be adaptive. Should a person’s refractive error change, the Orthokeratology lens can be replaced with new ones to correct for the changed prescription. Also, should a person wish to halt the procedure the lens wear can simply be stopped, and the cornea will revert to its original shape within 14 – 18 days allowing for alternative correction methods