Scleral Lens

1. What is a Scleral Lens?

The scleral lens (sclera lens) is a lens that sites over the cornea and sclera part of the eye to protect the eye. While drops are necessary with use of a scleral lens every few hours if an individual is wearing a scleral lens for severe dry eye use of drops is considerably less often, while allowing for clear vision- possibly perfect vision in the eye.

A Sclera lens is similar in form in some respect to contacts used for eye correction but are double the size and meant to protect the cornea of the eye. Unlike traditional contacts, scleral lenses are gas permeable (GP) contacts, rigid lenses made of durable plastic that transmits oxygen. Also known as rigid gas permeable lenses, RGP lenses, and oxygen permeable lenses.

GP can be used to correct vision and helpful for:

1. Correcting vision from long-term eye strain.
2. Prevention of blindness from cornea scaring by protecting the cornea from dry eye damage after damage to either the facial nerve, cranial nerve 7 (CN7).
3. Eyes with astigmatism, or other curvature issues.

2. NF2 and Severe Dry Eyes

Individuals with neurofibromatosis type 2 (NF2) commonly develop damage to cranial nerve 7 (CN7), the facial nerve.

Damage to CN7 results in extreme dry eye, an issue if untreated will result in corneal cracks and cornea scars and complete loss of vision in the eye. CN7, the severe dry eye would be the result of:

• The inability for the tear gland to produce tears to moisturize the eye when blinking.
• Inability to close the eye to blink.
• Inability to close the eyelid to hold fluids to maintain eye moisture.

Severe dry eye from CN7 damage requires the use of alternative fluids to maintain eye moisture. Options to maintain moisture are the use of different either; eye drops or eye gels. Eye drops dry in a few minutes, and while thicker gels last longer than drops, the thicker the gel, the less an individual will see from the eye.

Drop and gel options dissolve quicker in windy or dry environments, which can make it difficult to determine how often it is necessary to remoisturize before dryness can lead to cracks and permanent scars on the cornea.

3. Optometrists - Scleral Lens Fitters

Scleral Lenses are available worldwide, with different brands and manufacturers. One option in the United States and Canada is BostonSight® under the name PROSE (prosthetic replacement of the ocular surface ecosystem)

These lenses are available in different brands and which is ideal should be considered after reviewing all brand advantages and disadvantages.

Scleral lens fitters are the doctors who help select the right shape of the scleral lens for each patient, based on eye issues and eye shape. There are many brands and lens fitters worldwide.

Coming soon, a complete list of manufacturers, brands, and fitters around the world.

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Long-Term Dry Eye Needed of Cornea Replacement		Eye with PROSE Lens

4. Sources

1. All About Vision. "Scleral Lenses." http://www.allaboutvision.com/contacts/scleral-lenses.htm
2. All About Vision. "Lenses (RGP Or GP Contacts)." http://www.allaboutvision.com/contacts/rgps.htm
3. http://www.allaboutvision.com/conditions/meibomian-gland.htm
4. http://www.contactlenses.org/scleral.htm
5. https://www.news-medical.net/news/20120323/Relief-for-dry-eyes-through-scleral-contact-lenses.aspx
6. https://www.youtube.com/watch?v=P4hydjQVzns
7. https://www.youtube.com/watch?v=Oxs3cu3Ws0Y
8. https://www.youtube.com/watch?v=P4hydjQVzns
9. http://www.sclerallens.org/
10. https://www.lenntech.com/water-chemistry-faq.htm