Any eye condition for which contact lens correction is an option may be considered for modern scleral lenses. These lenses are successfully used by people
with visual impairment resulting from corneal diseases such as keratoconus, or after corneal transplants or corneal scarring. People suffering from pain, photosensitivity and discomfort caused by severe dry eyes may also benefit. In cases where corneal rigid gas-permeable lenses are capable of improving vision, but cannot be tolerated, scleral lenses may be the answer.
Improving vision in cases of irregular corneal surfaces
One of the main aims of scleral lens fitting is the visual rehabilitation of an irregular corneal surface (FIGURE 5), such as in primary corneal ecstasia (mostly keratoconus (FIGURE 6), keratoglobus and pellucid marginal corneal degeneration); other forms of corneal degeneration (such as Fuchs’ endothelial, map-dot fingerprint, Reis-Bucklers and lattice); corneal transplants (FIGURE 7) (post-penetrating
keratoplasty) and other forms of irregular astigmatism (corneal scarring after injuries, inflammation such as herpes simplex keratitis and complications during refractive surgery like radial keratotomy and LASIK etc.).
Relieving the symptoms of dry eyes and corneal dystrophies
Scleral lenses can be used to relieve symptoms such as pain, photosensitivity and discomfort. The following conditions
relating to/resulting from severe dry eyes can be treated:
- neurothropic keratitis
- keratitis sicca
- ocular cicatricial pemphigoid
- Sjögren’s syndrome
- Stevens-Johnson syndrome
- after acoustic neuroma surgery
- after surgery for trigeminal neuralgia
- after chemical and burn injuries
The following dystrophies can too be eased with scleral lenses:
- Fuchs’ endothelial dystrophy
- Map-dot fingerprint dystrophy
- Reis-Bucklers dystrophy
- Lattice dystrophy
The lenses also facilitate healing in cases of recurrent corneal erosion (FIGURE 8).
Scleral lenses provide mechanical protection and restore function in conditions such as scarred eyelids, entropion and ptosis. They also protect the cornea from friction with the eyelids during blinking.
Sport and other special circumstances
Scleral lenses can be helpful in all sporting environments. For swimming, diving and other water recreation the lens is a valuable option if visual correction is necessary. Contact sports, as well as working and taking part in sporting activities in dry and dusty environments also lend themselves to scleral lenses (dust seldom becomes trapped under the lens).
Warning: Swimming with scleral lenses in contaminated water may increase the risk of eye infection. It is advisable to wear tight-fitting goggles, and clean and disinfect the lenses afterward.
After swimming, wait at least an hour before removing the lenses, as they might adhere to the eyes a little more than usual.
Furthermore, because of their size and stability, scleral lenses are easier to handle for patients suffering from conditions affecting their manual dexterity (eg. Arthritis).