Keratoconus

Keratoconus is a progressive, non-inflammatory condition where the cornea becomes steeper and conical in shape.

It causes blurred vision and significant visual disability if not treated. The change in shape usually occurs over months or years but can change rapidly especially if the inner cornea breaks causing sudden swelling of the cornea and pain (acute hydrops). A change in prescription, increasing astigmatism should arouse suspicion and referral to an ophthalmologist for further investigation.

The aims of treatment are to stabilise the condition, halt any progression and maximise the patient’s vision. Keratoconus can be halted with corneal cross-linking (see treatments) and it is essential treatment is given as early as possible to minimise any change or reduction in vision.

Riboflavin drops are applied to the cornea followed by UV-A light which results in the formation of more bonds within the corneal structure causing it to stiffen and stop the progressive change of shape. This is an artificial acceleration of the normal stiffening of the cornea which occurs with age and causes keratoconus to naturally ‘burn out’ around the age of 40yrs old. Cross-linking has changed the course of the disease: markedly reducing visual disability, progression to advanced disease and the need for corneal transplant. 

Vision is maximised using glasses and contact lenses. Myopia, astigmatism and corneal irregularities can be corrected with implantable contact lenses, intracorneal ring segments / CAIRS or the Athens Protocol (combination of cross-linking and topography-guided laser to regularise the corneal shape).