Keratoconus
Causes, Symptoms, Diagnosis and Treatments
What is keratoconus?
Keratoconus is a progressive thinning of the central zone of the cornea, the front surface of the eye. As a result of this thinning, the normally round shape of the cornea is distorted and a cone-like bulge develops, resulting in significant visual impairment. The cause of keratoconus remains unknown, although recent research seems to indicate that it may be genetic in origin. Certain allergic and arthritic disorders, Down’s syndrome, chronic eye rubbing, overexposure to sunlight and contact lens wear have occasionally been associated with this condition.
Symptoms
- Blurred or distorted vision
- Frequent changes to your glasses prescription
- Increased sensitivity to light
- Difficulty with night vision
Diagnosis
Corneal imaging (topography or tomography) maps the shape of the cornea, often detecting keratoconus before it’s noticeable on a standard eye test.
Treatments
- Glasses — in the early stages of the condition, spectacles are usually successful in correcting the myopia and astigmatism associated with Keratoconus.
- Rigid contact lenses — as the condition advances, the cornea becomes highly irregular. Rigid contact lenses are then required to provide optimal visual acuity.
- Corneal cross-linking — for mild Keratoconus, strengthens the collagen bonds within the cornea to slow or halt progression, much like a wide belt supports a sagging stomach.
- Corneal graft surgery — in about 15% of cases, Keratoconus progresses to the stage where corneas that are significantly scarred or distorted, requiring replacement of the damaged tissue with a donor graft
Outcomes
Modern treatment is very effective at halting progression and preserving vision, especially when caught early.