In a keratoconus, the cornea of the eye becomes thinner and bulges like a cone. This deformation manifests itself in the person concerned mainly by a blurred or distorted vision noticeable. In addition, the vision usually deteriorates quickly. Keratoconus often develops only in one eye, later the second one also changes.
The exact causes of keratoconus are not yet fully understood. Apparently, those affected have changes in comparison to the healthy cornea, which makes the cornea less stable and thus more easily deformable. Genetic influences probably play a role in the development of keratoconus.
Light to medium keratoconus stages are usually treated well with contact lenses. If the corneal cone continues to increase, however, the contact lenses will no longer adhere well at some point. Then different operative methods are possible. So you can for example:
A relatively new method of treating keratoconus is called corneal crosslinking. Here, the doctor wears off the top cell layer of the cornea and then treats the eyes with vitamin B2 drops and UV radiation. This should improve the cross-linking of the molecules within the cornea and make them more stable and less deformable. The ocular malformation progresses more slowly.
So far, there is no causal treatment of keratoconus, a cure in the true sense is therefore not possible. With appropriate therapy, however, the eyesight of those affected can be improved.
Keratoconus is a malformation in which the cornea of the eye (cornea) gradually becomes thinner and bulges like a cone. A keratoconus usually occurs on both sides, but usually arises only in one eye.
The term keratoconus consists of the word part kerato-, which goes back to the Greek word kéras (= horn), and the Latin word cone (= cone) together.
Keratoconus is one of the most common abnormalities of the cornea. It occurs statistically in about 4 to 600 out of 100,000 people. However, the frequency of keratoconus varies according to the source of the literature. At the time of diagnosis, most people are between 15 and 30 years old.
While corneal change is more common in women than in men, according to some sources, other sources suggest that the disease is equally common in both women and men.
The exact causes of keratoconus (corneal cone) are not yet known. However, previous findings indicate that the molecular structure of the cornea differs slightly in those affected compared to people without keratoconus. Especially with the collagens and some enzymes there are deviations, whereby the cross-linking within the cornea is worse. As a result, it is less stable and gives way more easily.
There is probably a genetic component in the development of this eye disease. This is because the risk of keratoconus is increased if cases of this corneal change have already occurred in the family.
The thinning and conical protrusion of the cornea should also occur more frequently in connection with various diseases, such as in:
Also, regular, extreme eye rubbing should be able to contribute to the emergence of keratoconus, the underlying mechanisms are unclear.
Some experts believe that years of contact lens wear favors keratoconus. However, this may only be the case in those who had previously unrecognized, undiagnosed keratoconus.
A keratoconus (corneal cone) can have a variety of symptoms that can change with the progression of the disease. Possible symptoms include:
Usually only one eye forms a keratoconus. Later, the cornea also changes in the second eye.
To diagnose a keratoconus (corneal cone), the ophthalmologist examines the victim's eyes and asks him about existing complaints and illnesses. To diagnose keratoconus, various eye examinations can contribute, such as:
For a Keratokonus (corneal cone), there are various therapy options. Which treatment is right depends on how advanced the keratoconus is in the affected person and how quickly the eye disease worsens.
Lighter keratoconus cases can usually be treated with spectacle lenses or contact lenses. However, when the keratoconus is more advanced, contact lenses often can not be worn because they can hold badly on the cone-shaped cornea and fall out. In later stages, therefore, eye surgery (corneal transplantation) may be necessary in which the cornea is completely or partially replaced by donor material. Corneal grafts are usually well tolerated.
Frequently, contact lenses are sufficient to treat keratoconus.
Eye surgery may be appropriate if:
Depending on which part of the cornea protrudes and how advanced the keratoconus is, different operative methods can be considered, for example:
In this method, during eye surgery, the doctor inserts two small, half-moon, plastic ring segments between the corneal layers. In this way, the conical protrusion flatter and the vision improves. Also, contact lenses usually fit better after such an intervention again. The corneal implants can be removed if necessary.
In advanced cases of keratoconus, which are associated with scarring and thinning of the cornea, a corneal transplantation (keratoplasty) may be useful - a complete or partial replacement of the own cornea against donor material. There are different ways:
The so-called corneal cross-linking is still a relatively new method to treat keratoconus in its early stages. Before the actual treatment, the uppermost layer of the cornea (corneal epithelium) is removed. Subsequently, the affected person drops vitamin B2 (riboflavin) into the eye and is then irradiated for 30 minutes with UV light (320 nm). During the irradiation is further dripped so that the cornea does not dry out.
This method is intended to stimulate the cornea to form more crosslinks and thereby strengthen them. The cornea becomes slightly stiffer and less deformable in this way. The disease progresses more slowly. The corneal cross-linking is especially in early keratoconus stages in question.
A keratoconus proceeds untreated mostly slowly, but in spurts. In part, the disease comes for a long time by itself to a standstill. Although the "corneal cone" can not heal in the true sense, a treatment can slow down the progression of the disease and relieve discomfort.
About one in ten sufferers experience so-called acute keratoconus. This complication usually occurs when, in an untreated corneal cone, the lowest two layers of the cornea tear as a result of the constant stretching. Then aqueous humor can penetrate the cracks, causing the cornea to cloud. In the affected person, this is noticeable by the following symptoms:
Since genetic factors probably play a role in the development of keratoconus (corneal cone), the disease can not really be prevented.