Keratoconus is a thinning disorder of the cornea that results in distortion and reduced vision.
We see through the cornea, which is the clear outer lens or “windshield” of the eye. Normally, the cornea has a dome shape, like a ball. Sometimes, however, the structure of the cornea is just not strong enough to hold this round shape and the cornea bulges outward like a cone – a condition known as keratoconus.
As the disease progresses, the cone becomes more pronounced, causing vision to become progressively more blurred and distorted.
Because of the cornea’s irregular shape, patients with keratoconus are usually short-sighted with astigmatism that is not fully correctable with glasses. In moderately severe cases rigid gas-permeable contact lens are the best way to correct the vision.
LASIK (Laser-Assisted In Situ Keratomileusis, a procedure that permanently changes the shape of the cornea, the clear covering of the front of the eye, using an excimer laser) is never performed on keratoconus patients and severe cases require a corneal transplant. If the eyes are suitable for corneal cross linking, this is the procedure of choice for keratoconus.
Visual loss occurs primarily from irregular astigmatism and myopia, and secondarily from corneal scarring.
Patients with keratoconus may report the following:
- Multiple unsatisfactory attempts to obtain optimum spectacle correction
- Monocular diplopia or ghost images
- Itchy eyes