Effective Treatment for Irregular Corneas
An irregular cornea generally causes problems or limitations with vision, and can be more complicated to correct with standard eyeglasses or contact lenses. If eyeglasses and regular contact lenses aren’t helping you see clearly due to an irregular cornea, scleral lenses may be the perfect solution to give you sharp, comfortable vision. Eye doctors will evaluate your cornea using first-rate skill and the latest optometric technology. If we find that you are a good candidate for treatment with scleral lenses, we’ll fit you expertly with a pair of these premium, specialized contacts.
What causes irregular corneas?
A large variety of causes may be responsible for irregular corneas. Some of the most common culprits include:
- Keratoconus
- Prior eye surgeries, such as LASIK or cataracts
- Eye injuries or burns
- Scarring after an eye infection
- Corneal ulcers
- Severe cases of dry eye
- Congenital defect
- Pterygium (conjunctival degeneration)
- Pellucid marginal degeneration
How is vision corrected when you have an irregular cornea?
When the cornea is only mildly misshapen, eyeglasses may still be able to correct vision effectively. Yet when eyeglasses are no longer able to provide crisp eyesight, contact lenses are usually the next option recommended by optometrists. Soft contact lenses may be prescribed initially for mild to moderate cases of vision distortion due to an irregular corneal surface. When soft lenses are ineffective, more advanced specialty lenses, such as hybrid (soft/rigid) lenses, customizable soft lenses or scleral lenses are typically recommended as the next step.
What are scleral lenses?
A scleral lens rests like a bridge over the cornea, and not on it. A ring, termed a flange, sits on the white of your eye (the sclera) and gaps between your eye and the contact lens are filled with tears. Corneal scarring or an extremely irregular corneal surface may make it impossible to wear standard contact lenses comfortably and with a good fit. With their extra-large diameter, gas permeable scleral lenses offer a great alternative.
The unique shape of scleral lenses allows them to be used for many hard-to-fit ocular conditions, such as keratoconus, pellucid degeneration and where there is a great deal of corneal scarring. Your sclera tissue is not as sensitive as the cornea, and therefore scleral lenses are usually very comfortable – even when worn on a daily basis.
There are three main types of scleral lenses, with the differences being in size and where the lenses meet your eye’s frontal surface. Corneo-scleral lenses have a wide diameter and rest close to the seam of your sclera and cornea. Mini-scleral lenses span over your entire cornea, and full scleral lenses are the largest type, creating the greatest clearance space between the contact lens and your cornea. Our St. Louis optometrist will evaluate your cornea and recommend the best type for your eyes.
Who is a good candidate for scleral lenses?
In general, any individual who wants to optimize their vision with contact lenses can be a suitable candidate for scleral lenses. However, these specialized lenses are most appropriate for people with the following conditions:
- Hard-to-fit eyes: if you can’t be fit well with traditional gas permeable lenses, or lenses tend to pop out of your eye easily, scleral lenses may give you a more secure fit.
- Dry eyes: when the tear film that coats your eyes is insufficient, conventional contacts may be uncomfortable or painful. Scleral lenses have a large gap between the contact lens and your cornea, and this space acts as a place for tears to collect. More moisture thereby remains on the surface of your eyes.
- Irregular corneas: no matter what the cause of your irregularly shaped cornea, scleral lenses will usually give you much clearer vision than eyeglasses or standard contacts.
- Post-corneal surgery: surgeries, such as corneal transplants, often leave you with vision that is not fully normal. Post-surgery scleral lenses offer sharp, comfortable eyesight while simultaneously protecting the delicate eye tissues from any damage to the graft.
Benefits of scleral lenses
Many individuals report that their vision is extremely crisp with scleral lenses, in comparison to soft contacts. As rigid gas permeable contacts, they are easy to handle and highly durable, and the extra-wide design makes them less likely to dislodge accidentally from your eye. Additionally, scleral lenses are associated with a decreased risk of eye complications.
To find out if scleral lenses can help improve your vision, contact us for an appointment at our local vision center.