A scleral contact lens is a large diameter semisoft contact lens that rests on the sclera i.e. the white Portion of an eye. It is also known as ocular surface prosthesis.
Design:- The modern scleral lenses are made of a highly oxygen permeable and are unique in their design. Because these lenses sit on the sclera, for the patients whose cornea is sensitive or irregular it’s best suited as it does not touch cornea at all. Artificial tears occupy the space between the cornea and the lens. The tears mask these corneal irregularities allowing vision to be restored comfortably. Thus, helps in providing Best Corrected Visual Acuity extreme comfort to the patient.
Pic courtesy to google (Fitting Scleral contact Lens with the gape between lens and cornea)
Types of Scleral Contact Lens
1. Semi-scleral lenses – are larger than conventional rigid gas permeable lenses and rest near the junction between the cornea and the sclera.
2. Mini-scleral lenses – vault over the cornea and rest on the anterior sclera just beyond the limbus.
3. Full scleral lenses – are the largest scleral lenses among the scleral lens family and provide a significant amount of clearance between the back surface of the lens and the cornea.
1. Semi-scleral lenses – are larger than conventional rigid gas permeable lenses and rest near the junction between the cornea and the sclera.
2. Mini-scleral lenses – vault over the cornea and rest on the anterior sclera just beyond the limbus.
3. Full scleral lenses – are the largest scleral lenses among the scleral lens family and provide a significant amount of clearance between the back surface of the lens and the cornea.
Types of Scleral Contact Lens:
• Extremely comfortable(one cannot feel the lens into the eyes).
• Provides good centration and stability than lenses like RGP, soft lens, etc.
• In patients with the damaged corneal tissue, it helps in soothing the tissue by supplying preservative-free saline as well as prevents from friction with eyelids.
• Respective eye movement is difficult with corneal lenses (RGP and Rose K2 Contact lenses), is effortless in scleral lenses.
• Easy to perform an activity like running, driving, playing sports, etc. without worrying about the lens.
• A scleral contact lens can correct full refractive power, which sometimes is not possible with the other lenses.
• Scleral lenses act as a backup in patients who are considered as poor contact lens candidates.
• Scleral lenses are designed to accommodate any degree of corneal steepness or irregularity.
• Scleral lenses can also be used for nonsurgical rehabilitation of severe corneal ectasia and dry eyes.
Disadvantages:-
High cost
Candidates for Scleral Contact Lens:
• Keratoconus
• Terence Marginal Corneal Degeneration
• Pellucid Marginal Corneal Degeneration
• Stevens-Johnson syndrome (SJS)
• Chemical injury
• Ocular Surface Phemphigoid
• Dry eye due to primary Sjogren’s syndrome
• Mild Ptosis
• Patients with significant refractive errors who are inactive sports e.g. cricket, hockey, etc.
If you are interested in scleral lenses and would like to know more about whether they are right for you, please make an appointment or contact us.