Corneal reshaping with contact lesnes is also known as orthokeratology

Introduction to Corneal Reshaping

Corneal reshaping uses contact lenses to correct myopia. Other names for the therapy are orthokeratology and corneal refractive therapy.

Corneal reshaping is now a very advanced therapy and as it is less invasive than surgery and cosmetically preferable to wearing glasses many people are choosing it as a way of correcting myopia. However in order for corneal reshaping to succeed both the patient and the eye care professional must be well educated in how it works to ensure the safety of the eye.

The corneal reshaping process

Corneal reshaping, also known as corneal refractive therapy or orthokeratology, first came about in the early 1960s. The intention of the therapy was to errantly transform the way the cornea is shaped by wearing contact lenses when asleep. These lenses are made of high oxygen permeable materials. The therapy involves thinning the epithelial lining the center of the eye and thickening the stromal area.

Research about corneal reshaping

Corneal reshaping is not effective for everyone. For some the improvement in vision is temporary. Results can be erratic at times.

There were three research important studies conducted from the seventies to the eighties that studied the results of lenses with a spherical design. The study looked into the effects if the corrective corneal lenses were worn for waking hours only and it was found that vision correction using this method was quite slow. These contact lenses had a refraction divergence of about –2.50 diopters. They were worn from between 132 days to 17.7 months. These studies proved that myopia could be reduced to less than 75%.

In the mid 1990’s this type of eye therapy too a back seat until more advanced materials and designs brought hope. The new contact lenses could be worn all through the night and brought quicker, more noticeable results.

The latest studies have reported substantial results within the first month. Rapid correction of baseline refractive error has been reported through the first 24 to 72 hours. Recovery is expected to take place over a period of two weeks.

Side effects of corneal reshaping

Side effects have been reported with corneal reshaping contact lens therapy. They are as follows:

• Asymptomatic corneal pigmentation rings that are reversible with appropriate treatment
• An increase in higher order aberrations of the sclera, particularly spherical aberration
• Corneal ulcers
• Microbial keratitis (which if left untreated can lead to blindness.)

The most alarming side effects have been reported with the use of these contact lenses on children. This is why corneal reshaping therapies using contact lenses are rarely implemented in the case of children or adolescent.

Research that compares effectiveness of the use of corneal reshaping contact lens versus wearing eyeglasses has discovered that corneal reshaping contact lenses slow the degradation h of the eye 46% through a span of two years. However, these findings are controversial mainly because of the side effects (keratitis and infections) associated with corneal contact lens reshaping.

Preventing the side effects of corneal reshaping

The best way to combat the side effects of corneal reshaping treatment is to take measures to prevent complications. It is also important that the person receiving the treatment understands the implications of any side effects.

In the United States, the Food and Drug Administration (USFDA)

The United States Food and Drug Administration (USFDA) stipulates that contact lens manufacturers should get an approval on product labeling information that includes package supplements, patient counseling and usage instruction brochures, guidelines for trained implementation etc.

Here is some advice that can help prevent the side effects of corneal reshaping:

• Never store or rinse your contact lenses in tap water
• Follow your manufacturer’s guidelines when it comes to cleaning and disinfecting your contact lenses.
• Clean them every time you remove them from your eyes.
• Seek advice from our doctor if you suffer discomfort, redness or blurring of vision while using the lenses
• Visit your practitioner every six months to check the progress your corneal reshaping and the fit contact lenses, even if you aren’t experiencing side effects

Guidelines for practitioners should also be followed in order for the corneal reshaping procedure to work. This is why corneal reshaping contact lens manufacturers certify eye care practitioners before allowing them to prescribe their products.

Here are some tips for eye care practitioners that are prescribing corneal reshaping therapy:

• It is advisable to inform patients that the corneal reshaping process is halted when the patient stops using the lenses. They must also be warned that the lenses have not been scientifically proved effective in slowing the development of myopia in children or adults
• Practitioners should provide their patients with written briefs that include simple graphics so that patient has instructions on how to use the corneal reshaping lenses
• Patients should be given t emergency contact options so they can seek immediate treatment if something goes wrong with the lenses
• Practitioners must seek a consent form and a pediatric assent form before agreeing to give corneal reshaping contact lens wear. This protects both the practitioner and the wearer