Keratoconus

This is where the cornea, the clear layer over the iris, becomes thin and starts to bulge forward into a cone shape. Keratoconus is a progressive condition and affects each suffer differently. The cone shaped cornea in keratoconus affects the way light enters the eyes and causes distortion in the vision. Keratoconus will not cause blindness but can severely affect your vision. Keratoconus can be detected at your routine eye test.  Keratoconus is more common in non-Caucasians.

• Blurred vision

• Frequent changes into vision

• Frequent changes to your prescription

• Frequent increases in astigmatism

• Distortion in vision, where straight lines appear bent or wavy

• Glare or sensitivity to light

• Redness of the eyes

• Swelling of the front of the eyes, hydrops, caused by fluid entering the cornea, can be painful and sudden

• Scarring of the cornea

• Keratoconus has also been associated with - Overexposure to UV

- Longstanding poorly fitted contact lenses

- Excessive eye rubbing and eye irritation.

The exact cause of keratoconus is unknown however in some cases they may be genetic and environmental links or factors. Keratoconus usually starts in the teens to early 20’s; the vision then progressively deteriorates over the next one or two decades.

There is further research into the possible cause of weakening of the cornea due to an imbalance of enzymes in the corneal tissues. This causes oxidative damage by free radicals and this causes keratoconus; forward bulging cone shape cornea.

There is no cure for keratoconus but it can be managed.

1. Do not rub your eyes; patients with keratoconus can damage the thin corneal tissue by rubbing them. If you have allergies that cause itchy eyes, allergy eye drops are available to prevent the itchy feeling and stop you from rubbing them

2. In the early stages of keratoconus glasses can be used to give clearer vision

3. Contact lenses can be used to correct your vision. Contact lenses will not stop keratoconus but may give you better vision than glasses. There are many contact lens options, one option is soft contact lenses for simpler prescriptions and they are very comfortable, soft contact lenses can also be custom made

4. Hard contact lenses to improve the vision, hard contact lenses give a more uniform surface by covering the cone shaped cornea

5. ‘Piggybacking’ contact lenses, this where a soft lens is fitted to the eye, with a hard contact lens over the top. This is to improve comfort and give better clarity of vision

6. Hybrid contact lenses have a hard contact lenses center with a soft contact lens skirt. This improves comfort and gives the wearer crisper vision

7. Special keratoconus hard contact lenses, specialised lenses for keratoconus sufferers

8. Scleral or semi scleral contact lenses, where the edges of the contact lenses sit on part or all of the sclera (white of the eyes) this stabilises the contact lens and relieves pressure from the bulging corneal cone

9. Prosthetic contact lenses for very advanced keratoconus; it is an advanced scleral lens design.

10. Intacs is a small curved device that is surgically placed into your cornea to help flatten the corneal cone and improve vision.

11. Collagen cross-linking CXL uses a special UV light and vitamin B2 drops to strengthen, flatten and stiffen the cornea. This treatment is used in progressive keratoconus and is a newer treatment.

12. Corneal transplant is when all or part of your cornea is replaced with a healthy cornea donor.

Topography-guided conductive keratoplasty is a newer treatment that is still being studied. It is where radio waves are used to reshape the cornea.