Keratoconus Treatment At Moorfields Eye Hospital

Keratoconus is a progressive condition that leads to gradual thinning and bulging of the cornea. Doctors often explain to the patient that their eye is becoming shaped more like a rugby ball rather than a spherical football. Keratoconus occurs in around 1 in 2000 people in the UK and appears to be more common in people with asian or middle eastern ancestry (in whom frequency is 1/400). 

Keratoconus always affects both eyes, although very commonly, one eye tends to be significantly worse than the other. Most cases of keratoconus are picked up on routine screening by opticians who may notice rapid changes in your glasses prescription and increasing astigmatism. As corneal bulging increases, patients typically become more short sighted and develop more astigmatism. Vision can become difficult to correct with glasses. In some instances a spontaneous split can occur in the cornea (corneal hydrops) leading to a sudden drop in vision.

Keratoconus tends to begin during teenage  and continues to progress up to the late 30's, after which it tends to slow down and remain stable. Rapid progression seems to occur during teenage and early 20's. Unfortunately, if the condition isn't treated early on with collagen cross linking, patients are left with an abnormal shaped cornea that requires a contact lens to see well.

Keratoconus is a very variable disease and can be very mild in one person and not progress very much, whilst being severe and rapidly progressive in other cases. Keratoconus is a type of corneal ectasia and is one of a spectrum of similar diseases (pellucid marginal degeneration, keratoglobus)

Why does Keratoconus matter?

The cornea is the main optical component of the eye. The cornea helps focus images onto the retina at the back of the eye where it is perceived by the brain. As the cornea begins to bulge in keratoconus the regular optics of the cornea are distorted and hence it is difficult to focus a single clear image onto the retina. This can result in distortion, ghosting and multiple image formation. Keratoconus patients often find driving at night difficult due to multiple images, glare and haloes.

Unfortunately, as keratoconus progresses it becomes increasingly difficult for conventional spectacles to correct vision. Most keratoconus patients achieve their best vision with a rigid contact lens which works by arching over the bulging cone of cornea and artificially creating a smooth spherical surface that is optically superior.