Understanding Scleral Lenses
What are scleral lenses?
Scleral lenses are large diameter rigid gas permeable lenses that range from 14 mm to over 20 mm in diameter. They are termed “scleral” lenses because scleral lenses completely cover the cornea (the clear dome of tissue that covers the colored part of the eye) and extend onto the sclera (the white part of the eye that forms the outer wall of the eye).
What are the advantages of scleral lenses?
Large diameter scleral lenses offer certain advantages over corneal lenses. First, large-diameter lenses may be more comfortable than corneal lenses. The cornea is one of the most highly sensitive tissues in the body. The conjunctiva (soft, clear tissue that lies over the sclera) is much less sensitive than the cornea. Lenses that rest primarily or exclusively on the conjunctiva may induce less sensation than smaller lenses that rest upon the cornea. This is why scleral lenses are extremely comfortable.
In some patients, corneal tissue is damaged. Because scleral lenses do not touch the cornea, the cornea is bathed all day long with preservative free saline to rejuvenate the ocular surface. Scleral lenses extend under the upper and lower lids and rarely dislocate. Scleral lenses demonstrate excellent centration and stability.
Who could potentially benefit from scleral lenses?
Patients with irregular corneas, patients with conditions that affect the tear film, and patients with refractive error (nearsightedness, farsightedness, astigmatism and presbyopia) who are unable to wear other forms of correction could benefit from scleral lenses.
Conditions such as keratoconus and pellucid marginal corneal degeneration cause irregularity of the cornea. Surgery (keratoplasty, refractive surgery) can also lead to corneal irregularity. If the cornea is not smooth, vision will not be easily correctable with spectacles or most soft contact lenses. Scleral lenses mask this irregularity and allow for improved vision by providing a smooth front surface.
Some patients have disorders that affect the quality or quantity of tears that help to keep the eye’s surface smooth and healthy. Dry eye syndrome, graft vs. host disease, Sjögren’s syndrome, Stevens Johnson syndrome, and neurotrophic keratopathy are examples of such conditions. Some inflammatory conditions, including limbal stem cell deficiency and ocular cicatricial pemphigoid, also cause serious damage to the front surface of the eye. Patients who cannot close their lids completely may also experience problems with the health of the surface of the eye. The fluid reservoir beneath a scleral lens may improve comfort, and may allow the corneal surface to heal.
Patients who need visual correction, but are unable to wear other contact lenses, may find scleral lenses more comfortable than other lens designs.
You may benefit from scleral lenses if you have one of the following conditions:
- Post-corneal transplant
- Pellucid marginal degeneration
- Severe dry eyes
- Graft versus host disease
- Sjögren’s syndrome
- Stevens-Johnson syndrome
- Neurotrophic keratopathy
- Chronic inflammatory conditions
- Limbal stem cell deficiency
- Ocular cicatricial pemphigoid
- Other corneal conditions
Are scleral lenses new?
Scleral lenses were the first contact lenses described in medical literature in the late 1800s. However, due to manufacturing challenges and the lack of oxygen transmission through early lenses, scleral lenses did not become popular at that time. During the course of the next century, corneal rigid gas permeable lenses and soft contact lenses became increasingly popular.
Corneal rigid gas permeable lenses and soft lenses could not solve some of the problems caused by corneal irregularity and other eye diseases. Scleral lenses gained popularity in the 1980s when high oxygen material became available and could be reliably manufactured with more sophisticated designs.
Scleral contact lenses in complicated cornea case
"Dr. Butler and staff are knowledgeable and professional, and do their work with respect and compassion!! I was diagnosed with keratoconus after 2 years of vision problems, and was referred to Vision Plus for specialized lenses. Dr. Butler's amazing and caring staff, especially Dawn, stepped in with devotion and compassion and spent a tremendous amount of time fighting with my insurance company to cover the full cost of these expensive lenses. After many weeks and a ton of effort they succeeded!!! I finally got fit for lenses and I can see clearly for the first time in years!! Thank you Dr. Butler, Dawn, and the entire Vision Plus staff!"
"I been having issues with my eye sight for many years now and after many eye exams i never achieved optimal vision after an exam at lensCrafter i was diagnosed with a condition call keratoconus they then referred me to dr butler here at vision plus and after the eye exam with dr butler i was amazed at the results i never had vision as clear as it is now words cant explain how amazing my vision is i highly recommend dr butler and his staff here i wouldn't go anywhere else thanks doc for the 20/15 hd vision"