1. Special Gas permeable contact lenses for keratoconus-ROSE K
Glasses and soft contact lenses often cannot provide adequate visual acuity because of irregular astigmatism. Specially designed gas permeable contact lenses are usually the preferred treatment. GP lenses vault over the cornea, replacing its irregular shape with a smooth, uniform refracting surface to improve vision.
Fitting contact lenses on an eye with keratoconus often is challenging and time-consuming and must be fitted by specially qualified contact lens optometrists.
2-Scleral contact lenses for keratoconus
Scleral lenses are the most common and most successful treatment for patients with keratoconus pellucid marginal degeneration, post corneal transplant, post-refractive surgery complications, irregular corneas and other conditions requiring a specailist lens.
Scleral contacts are larger than standard gas permeable contacts and have a diameter equal to or greater than that of soft contact lenses. Scleral GP lenses rest on the sclera and vault over the misshapen cornea of a person with keratoconus, for better vision.
Elean optometrists have undergone highly specialised training to fit these lenses for patients with complex eye conditions.
They are suitable for post corneal grafts and keratoconus. They are also known to reduce dry eye conditions. The major advantage of these highly specialized lenses is the comfort which soft lenses provide and the excellent vision and durability that gas permeable lenses provide.
Scleral lenses have been reinvented since the 1980s and are now the top lenses being prescribed worldwide for irregular corneas.
- Excellent visual acuity for the most complicated eyes-Patients with keratoconus have a clearer vision with scleral lenses than with glasses. With glasses, patients usually see 6/24 whereas with scleral lenses their vision typically improves to 6/6 or even 6/5. 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.
- Durability lasting 2- 3 years
- Amazing 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”.
- Do not touch the cornea causing scarring like gas permeable lenses do.
- Reduce the progression of keratoconus.
- Protect your eyes and prevent dryness.
Scleral lenses are custom-made and fitted for each patient, which means that they require considerable expertise and more time than regular 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.
What is Keratoconus?
Keratoconus is a progressive eye disease in which the cornea normally thins and begins to bulge into a cone-like shape. This cone shape deflects light as it enters, causing distorted vision.
Keratoconus can occur in one or both eyes and often begins during a person’s teens or early 20s.The cornea is a very important part of your eye. Light enters the eye through the cornea, which refracts, or focuses, the light rays so that you can see clearly. With keratoconus, the shape of the cornea is altered, distorting your vision. Keratoconus can make some activities difficult, such as driving, typing on a computer, watching television or reading.
As the cornea becomes more irregular in shape, it causes progressive myopia and irregular astigmatism to develop, creating additional problems with distorted and blurred vision. Glare and sensitivity to light also may occur.
keratoconic patients experience changes in prescription every time they visit their optometrist. Keratoconus usually affects both eyes, though symptoms in each eye may differ.:
The rate of progression varies. Keratoconus will often progress slowly for 10 to 20 years and then suddenly stop. As the condition progresses, the most common symptoms include:
- Increased blurring and distortion of your vision
- Increased nearsightedness or astigmatism
- Frequent eyeglass prescription changes
- Inability to wear contact lenses
Occasionally, keratoconus can advance rapidly, with sudden swelling of the cornea and development of corneal scarring. Scar tissue on the cornea causes the cornea to lose its smoothness and clarity. As a result, even more distortion and blurring of vision can occur.
What causes keratoconus?
Some researchers believe that genetics play a role, since an estimated 10 percent of people with keratoconus also have a family member with the condition.Research suggests the weakening of the corneal tissue that leads to keratoconus may be due to an imbalance of enzymes within the cornea. This imbalance makes the cornea more susceptible to oxidative damage from compounds called free radicals, causing it to weaken and bulge forward.
Risk factors for oxidative damage and weakening of the cornea include a genetic predisposition, explaining why keratoconus often affects more than one member of the same family.
Keratoconus also is associated with overexposure to ultraviolet rays from the sun,excessive eye rubbing a history of poorly fitted contact lenses and chronic eye irritation.
In addition, keratoconus is associated with:An eye injury, i.e., excessive eye rubbing or wearing hard contact lenses for many years. Certain eye diseases, such as retinitis pigmentosa, retinopathy of prematurity and vernal keratoconjunctivitis.