Keratoconus (keh-rah-toe-cone-us) is a non-inflammatory eye disorder in which the round dome-shaped cornea progressively thins causing a cone-like bulge to develop.
Hence the name keratoconus, from the Greek word ‘kerato’ (cornea) and ‘conus’ (cone-shaped).
Because those with keratoconus have irregular, cone-shaped corneas, glasses cannot conform to the shape of the eyes and thus cannot adequately correct the patients’ vision. The best solution, therefore, is scleral contact lenses, since they sit on the sclera without touching the cornea and deliver maximal clarity while being perfectly comfortable in most cases.
What are Scleral Lenses?
Custom-designed scleral lenses help patients with corneal irregularities achieve dramatic improvements in visual acuity and comfort. Scleral lenses vault over the cornea and rest on the sclera while avoiding the diseased cornea. This creates a new optical surface instead of the damaged cornea and prevents discomfort by resting on the sclera of the eye. Moreover, the reservoir of pure saline solution between the back surface of the lens and the front of the cornea ensures that the eye is always in a liquid environment – making it optimal for healing.
Both rigid gas permeable (GP) lenses and scleral lenses provide the eyes with sufficient oxygen. However, scleral lenses provide more comfort and stable vision than traditional GP lenses. In most cases, scleral contact lenses are the optimal choice of treatment for patients with keratoconus and irregularly-shaped corneas.
Two Major Benefits of Scleral Lenses for Keratoconus
1) Scleral Lenses Provide More Comfort
Our patients report comfort as the most prominent feature of the scleral lens. Throughout the fitting process, we survey our patients on how the lenses feel, and not surprisingly, the usual response we get is “fine” or “I can’t feel them at all”.
The size of a scleral lens is one of the reasons it is more comfortable than a traditional gas permeable contact lens. A traditional contact lens is much smaller, typically 9 -10 mm in diameter. With each blink, this contact lens moves a bit over the cornea and the lid tends to roll over the edge of the lens as well. Many patients report being unable to wear them for more than a few hours at a time due to discomfort.
The scleral lens, on the other hand, is larger in diameter and spreads its weight over a much greater, less sensitive area so that when you blink, the eyelid doesn’t catch the edge of the lens. Moreover, because the lens vaults over the bulging cornea, it protects the cornea from any abrasion caused by blinking or external irritants. Furthermore, the scleral lens is made up of highly oxygen permeable materials and provides a soothing bath of artificial tears that refresh the ocular surface.
2) Scleral Lenses Offer Improved Vision
Patients with keratoconus have a clearer vision with scleral lenses than with glasses. With glasses, patients usually see 20/200, whereas with scleral lenses their vision typically improves to 20/30 or even 20/20. Furthermore, because the lenses sit firmly on the eye, they offer more stable vision than traditional lenses. The scleral lens not only offers comfort but also improves vision acuity.
What Changes Will I Notice with Scleral Lenses?
Once you have been properly fitted for scleral lenses, you can expect to gradually see improvements in clarity, color and detailed contrast between multiple images and objects within your visual field. The comfort you’ll experience will enable you to wear your custom-made scleral lenses all day long so that you can keep doing all the things you enjoy – but with better vision.
Should I See An Eye Doctor Experienced in Fitting Keratoconus Patients with Scleral Lenses?
If you are interested in seeing whether scleral lenses are right for you, make sure that the eye doctor you visit has the knowledge and experience required to correctly fit the lenses on patients with keratoconus. Scleral lenses require precise customization, and every patient’s case of keratoconus varies in degrees of severity and corneal measurements.
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Original Website: www.abesamiseyecare.com