KERATOCONUS

Keratoconus is a disease of the cornea which manifests itself in a progressive thinning and bulging where the cornea becomes pointed and takes the form of a cone (protrusion). The consequence of this bulging is an irregular astigmatism (irregular deformation) causing a decrease and an irreversible distortion of vision that cannot be improved by glasses. In addition, this disease affects between 1 to 5 people per 1000, on the whole young people between 9 and 28 years old.

WHAT IS KERATOCONUS?

Physiology

The exact cause of keratoconus is not well known. However, among the main risk factors, we can note rubbing of the eyes (following allergic conjunctivitis) which could weaken the cornea. Chromosomal diseases such as Down’s syndrome are also associated with a higher incidence of keratoconus. In addition, there is a genetic predisposition which entails transmission of this disease in certain families (in 6% to 10% of cases).

Symptoms

Patients complain of progressive vision loss, distortion and deformation of vision and discomfort due to light (photophobia). The patient may not complain of any symptoms at the onset of the disease. Indeed, keratoconus can be detected during a routine examination or even during an examination to assess suitability for myopia surgery.

Diagnosis

The diagnosis of keratoconus is made on a body of clinical and paraclinical evidence (additional examinations). The ophthalmological examination reveals a decrease in vision and astigmatism. In severe cases, one can also find opacities and corneal scars. The main complementary examination is corneal topography. This geographic map of the cornea with colour scales allows you to see the relief of the cornea. Thus, one can detect an abnormal bulging of the cornea and screen or monitor for a keratoconus.

There are many treatments for keratoconus and the choice has considerably expanded in recent years. The treatments offered vary depending on the severity of the disease. From contact lenses to corneal transplants, the therapeutic arsenal is very broad.

Contact lenses (contactology)

Initially, the treatment of keratoconus is via a contact lens which makes it possible to flatten the surface of the cornea. This treatment is the best treatment for keratoconus with regard to vision. Moreover, hard lenses give better results than flexible lenses but are not always easily tolerated. In the case of advanced keratoconus, whereby patients can no longer tolerate the lenses, other treatments may be offered.