In keratoconus, the cornea is deformed forward in a cone shape.
The cornea also becomes thinner and therefore more prone to tearing.
In the early stages, vision problems arise which can still be corrected to a limited extent with glasses or contact lenses. Later on, special lenses can be used as well as keratoconus surgery and, in an emergency, a corneal transplant.
What is keratoconus?
Keratoconus is a progressive eye disease that causes vision problems due to the cone-shaped deformation of the cornea. If the eye disease is already advanced, glasses and contact lenses are no longer sufficient to correct the defective vision.
Keratoconus usually affects young people between the ages of 20 and 25. It also affects men much more frequently. Those affected usually have a deformation in both eyes, but it is possible that it is more pronounced in one eye than the other. (picture)
What are the symptoms of keratoconus?
- Progressive short-sightedness and irregular corneal curvature
- Distorted and blurred vision
- Glare and light sensitivity
- Frequent correction changes
- Limited vision at dusk and at night
What are the causes of keratoconus?
- The enzyme balance of the cornea is imbalanced
- Excessive UV radiation
- Poorly fitted contact lenses
- Frequent eye rubbing
- Chronic irritation of the eyes
- Genetic predisposition
There are new research findings that indicate that a weakening of the corneal tissue can lead to keratoconus. This may indicate an imbalance in the enzyme balance of the cornea. This imbalance can have various causes, excessive exposure to UV radiation being one.
Treatment options for keratoconus
In the early stages of keratoconus, it is possible to start treatment with glasses or well-fitted contact lenses. As the disease progresses, the cornea becomes thinner and more irregular. This makes it increasingly difficult to correct the visual impairment with contact lenses as well as glasses.
The treatment of keratoconus can vary greatly:
Corneal cross-linking:
Here, the natural collagen compounds are supported with vitamin B2 and thus ensure that the corneal tissue is stronger. The aim is to stop the eye surface from bulging.
Individually fitted soft contact lenses:
It has recently become possible to customize soft lenses so that they fit the keratoconic eye. These can be used in practice for mild to moderate keratoconus. The parameters can be precisely determined and the choice of a large diameter increases the stability of the lens on the eye.
Gas permeable contact lenses:
Gas permeable lenses are generally used when spectacles and soft lenses can no longer correct the visual impairment. GP lenses ensure that the irregular cornea becomes a smooth and even surface.
"Piggyback" contact lenses:
The piggyback principle actually works quite simply.
A soft silicone hydrogel is placed on the eye and a
GP lens is placed on top. This method is more comfortable to wear as the GP lens is fairly rigid.
Hybrid contact lenses:
A hybrid contact lens has almost the same principle as the piggyback method, except that one lens is used instead of two. The lens is a combination of an oxygen-permeable, rigid center and a soft edge.
These lenses combine the optical advantages of a GP lens with super wearing comfort. They have also been specially developed for keratoconus patients.
Scleral and semi-scleral lenses:
These contact lenses are made of gas-permeable material and have a very large diameter. Scleral lenses cover a large part of the sclera, whereas semi-scleral lenses only cover a small area of the sclera. Scleral lenses are more stable on the eye than conventional gas-permeable contact lenses, which move a little with each blink as they only cover part of the cornea.
Intacs:
Intacs ("Addition Technology") are transparent, arc-shaped corneal inserts. These are inserted into the periphery of the cornea during a 10-minute surgical procedure. The inserts in the cornea artificially reshape it. This procedure makes it possible to correct the patient's visual impairment using conventional correction options.
Keratoplasty with topographic map:
In keratoplasty, radio waves are delivered to the edge of the cornea to reshape the front surface of the eye. Topographic maps of the eye surface are often used to create individual treatment plans.
Corneal transplantation:
In some cases of advanced keratoconus, a corneal transplant is required. After such a corneal transplant, it can take several months for vision to stabilize. It is also possible that glasses or contact lenses will still be needed. There are also risks such as infection or even rejection of the transplant. For this reason, a transplant is only recommended if no other treatment has been successful.