Specialist Scleral Lenses: Could They Be The Solution to Your Keratoconus Problem?

Millions of people around the world use standard contact lenses to correct vision problems. Their popularity comes down to four things: they are highly effective, discreet, affordable, and easy to use. However, many people that would love to use standard lenses can’t. For various reasons, standard lenses are not suitable for some patients and may even cause more problems than they solve.

If you need vision correction for keratoconus or other corneal irregularities, then you will probably be amongst those who are not suited to use standard contact lenses. Due to the shape of your eye, most contact lenses would be unsuitable, likely to be irritating, and also potentially uncomfortable.

Thankfully, scleral lenses are a potential solution to your problem and are available at eye clinics in Dubai. Read on to find out how and why.

Why can’t I wear most contact lenses with keratoconus?

Keratoconus is a condition where the layers of the cornea gradually thin and become misshapen. The cornea is the transparent outer part of your eye that sits over the pupil and iris. Most people have a very similar dome-shaped cornea. But with keratoconus, the cornea begins to bulge as it thins to become more cone-shaped.

Many people are diagnosed with keratoconus at the point when they start to experience blurred or distorted vision, or headaches,  eye pain or sensitivity to light. Ophthalmologists use an instrument that shines a pattern of light onto the cornea to make a diagnosis. The shape of the reflection shows the curvature of the eye and reveals keratoconus. Alternatively, a computerized instrument may be used to make a 3D ‘map’ of the cornea.

How keratoconus affects vision

Unfortunately, keratoconus and other corneal irregularities affect vision. The cornea is the part of the eye that refracts (bends) light. It is responsible for focusing most of the light that enters the eye. Therefore, even minor irregularities in its shape can cause vision problems.

If you have keratoconus or any other corneal irregularity, then the atypical shape of your eyeball means it will be hard to find comfortable glasses or contact lenses or those that can improve vision. Standard contact lenses are designed to fit over about 75-80% of the cornea with the outer edges resting upon it. When the cornea is irregularly shaped, this can cause discomfort, distortion and irritation. Or it can prevent contact lenses from sitting correctly. You are unlikely to achieve both comfort and effective vision correction from standard lenses.

What are scleral lenses?

Scleral lenses are contact lenses with a larger diameter than most other types. They are specifically designed to fit over the entire corneal area and much of the sclera which is the white part of the eye, too.

Because scleral lenses form a generous dome over the whole cornea, they are very accommodating for corneal irregularities. This generous size means that they are usually a viable option for those with corneal irregularities, including keratoconus.

Scleral lenses are rigid gas-permeable lenses. They allow oxygen and carbon dioxide to pass through, which are important for good eye health. This also improves their comfort. Rigid gas-permeable lenses, including scleral lenses, are a good long-term solution because they are very agreeable for the wearer.

What are the alternatives to scleral lenses?

There are various alternative vision correction options for keratoconus patients, but their suitability will depend on how advanced the condition is.

Glasses

Correcting your vision with glasses is often possible in the early stages of keratoconus. It is a non-invasive treatment that suits many. However, as the keratoconus progresses, glasses often cease to be sufficient.

Soft lenses

There are some suitability shaped and sized soft contact lenses available that suit some keratoconus patients with only mild vision problems. But again, they often cease to be strong enough as the condition progresses to moderate vision loss.

INTACS

INTACS are thin plastic, semi-circular rings that can be inserted into the mid-layers of the cornea. They help to flatten the cornea, changing its shape and reducing the cone shape formed by keratoconus. Intacs reinforce the cornea, providing increased long-term protection against the progression of the disease.

INTACS cannot improve vision alone. Glasses or contact lenses may still be needed alongside them for functional vision.

Having INTACS implanted is a surgical procedure with some necessary recovery time, but it is reversible if necessary.

Corneal collagen cross-linking

Corneal cross-linking is a short, simple treatment. The cornea is saturated by custom-made eye drops and then illuminated by ultraviolet light to activate the treatment. Despite its apparent simplicity, corneal cross-linking shows excellent results by strengthening the cornea and arresting the development of keratoconus.

Collagen crosslinking is the natural anchoring that holds the shape of the cornea. By increasing the cross-linking through this treatment, the cornea holds its shape better.

However, corneal collagen cross-linking is not a vision correction method. It can, hopefully, slow down the progression of the condition in its early stages, but you are still likely to need glasses, lenses or a surgical procedure to have functional eyesight.

Corneal transplants

If keratoconus progresses to the point where functional vision cannot be achieved, even with glasses and contact lenses and the option of INTACS has been explored, then corneal transplants are possible.

In this surgical procedure, the diseased cornea is replaced with donated tissue. However, it is not a simple procedure and must be given a lot of consideration by both the surgeon and the patient.

Are scleral lenses right for me?

Keratoconus is a complex condition. As well as improvement to vision, there needs to be consideration of how the condition could be prevented from progressing further. Usually, lenses need to be accompanied by treatments that help to slow the disease.

Scleral lenses are an excellent option for those who would prefer to not wear glasses. They are also often ideal for when the condition has advanced to more moderate or severe keratoconus. At this point, soft lenses and glasses will often not suffice for clear vision.

For the right treatments for you and your particular case of keratoconus, you need to consult an experienced Gulf Eye Center ophthalmologist in Dubai or eye doctor in your local area.

AUTHOR BIO

Dr. Millicent M. Grim, Specialist Ophthalmologist & LASIK Specialist, is the Medical Director of Gulf Eye Center in Dubai. Since 2002, Gulf Eye Center’s highly qualified ophthalmologists and optometrists/ODs have been successfully treating a wide range of eye conditions using advanced techniques. They also provide comprehensive eye care and vision restoration procedures for people of all ages.