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Scleral Contact Lenses: Are They For You?

Scleral contact lenses are large, gas permeable lenses that rest on the white part of the eye known as the sclera. This differs from soft contact lenses which we fit to the cornea, the dome-shaped front of the eye. This unique design allows the lens to functionally replace the irregular cornea with a smooth optical surface to correct vision problems such as keratoconus (thinning and conical protrusion of the cornea) and other corneal irregularities. The space between the cornea and the back surface of the scleral lens acts as a liquid reservoir. This reservoir is filled with tears and provides comfort by lubricating the surface of the cornea to reduce dry eyes. 

Practically a scleral lens is a prosthetic cornea that recreates a perfect optical surface and makes vision a whole lot better. Let’s look at the following images that show what these menses look like:

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Scleral contact lenses are custom-made for patients and can provide better comfort and vision for those who have severe forms of:

• Keratoconus

• Ocular surface diseases (Sjogren’s, Steven’s Johnson Syndrome)

• Irregular astigmatism

• Highly irregular corneal transplants

• Post-refractive surgery complications (LASIK, PRK)

• Dry eye

Previously, scleral lenses have been reserved for only complex corneal and contact lens cases but are now gaining popularity and are being used for normal patients. Its distinct design provides increased comfort and stability on the eye leading to consistent vision, reduced glare and reduced dryness. Patients that have experienced poor comfort or vision with regular contacts may be good candidates for scleral lenses. 

Sources:

http://www.reviewofcontactlenses.com/content/d/rgp_lenses/c/52262/
http://www.allaboutvision.com/contacts/scleral-lenses.htm
http://cdna.allaboutvision.com/i/contacts-2016/scleral-lens-diagram-330×220@2x.jpg
http://cdna.allaboutvision.com/i/contacts-2016/scleral-lens-in-eye-330×220@2x.jpg

Vision Correction for High Prescriptions

Implantable Collamer Lens (ICL)

What is ICL?

Implantable collamer lens implants help patients see better without glasses or contacts. Unlike traditional contact lenses that go on the surface of the eye, the ICL is positioned inside the eye between the iris and the crystalline lens. Once Implanted, the lens stays indefinitely in the eye. However, if your vision changes dramatically over time, the lens can be easily replaced or removed and hence this procedure is reversible!

Who is a good candidate?

• High Myopes

•Patients between the ages of 21-45

• Patients with little or no astigmatism

• Patients with average or thin corneal thickness who may not be Lasik or PRK candidates

• Stable refractions with less than 0.50 diopters of change in two years

• Dry eye patients

Procedure

The ICL procedure is a short 15-minute outpatient procedure. Prior to the implantation of the Visian ICL, you will receive topical anesthetic drops to minimize discomfort. The doctor then creates a micro opening to insert the lens. The lens is folded and loaded into a small cartridge and as the lens is injected, it gently unfolds in your eye.

It is a simple procedure with fast recovery and provides youwith a fast vision change. So, if you are tired of bulky eyeglasses and contacts, ICL implants may be an option for you.

Overnight Vision Correction

Wouldn’t it be great if you could correct your eyesight and reduce your dependence on glasses or contact lenses — without having to undergo eye surgery? Orthokeratology (ortho-k) is the fitting of specially designed gas permeable (GP) contact lenses that you wear overnight. While you are asleep, the lenses gently reshape the front surface of your eye (cornea) so you can see clearly the following day after you remove the lenses when you wake up. GP contact lenses are not the same as the soft contact lenses that you may already wear; instead they are made of a firm, durable plastic that transmits oxygen.

How does an Ortho-K lens work?

The central portion of the lens fits closer to the eye than a standard contact lens exerting a gentle pressure. The outer part of the lens surrounds the central visual zone and is farther away from the cornea, allowing room for the cornea to change shape:

orthokeratology

 

Ortho-K lenses are custom made for each individual, but not everyone qualifies for this corneal refractive therapy. Two important factors that determine the candidacy for orthokeratology includes the curvature of the eye and the prescription. Your eye care practitioner will measure the exact shape of your cornea and prescribe lenses with the curvature, size, and corrective power that suit your eyes. Ortho-k is recommended for low to mild nearsightedness (-5 diopters or less).

When you begin to wear ortho-k lenses, you will likely have mild awareness of the lenses on your eyes until you fall asleep. Because the corneal reshaping effect is temporary, little risk is involved, and you can discontinue wearing the lenses at any time.

In summary:  no glasses, no daytime contacts, no surgery, 20/20 vision…no kidding!

 

Blog contribution by Eric Saidi, Optometry Intern, College of Optometry, Western University of Health Sciences.