The word is composed of the Greek expression Keratos for “horn” and conus for “conical”. In the human population Keratoconus is found in at least 1:2000. Although the first cornea transplantation has been carried out already in 1888, still today in spite of extensive studies the causes for keratoconus are not completely known.

Genetic causes are a probability; a divergence of the biochemical structure of the cornea has also been observed.

Keratoconus leads to an increased protrusion of the cornea. Since the cornea is an important component of the eye´s optic this protrusion leads to a series of different symptoms: oscillations of visual acuity in spite of glasses or contact lenses, the appearance of halos around light fonts (halos or ghost images) and a major sensibility to light and dazzle.  

Every second patient suffers more or less from some kind of hyper-sensitivity such as e.g. dry eyes, strong sensitivity to light or general diseases such as skin problems, soft-tissue rheumatism, allergies, and asthma or thyroid insufficiency.

It is not possible to actively prevent keratoconus as far as current knowledge shows. With high probability a genetic disposition is an additional cause for the disease.

It makes sense though, not to strain the eye and the cornea by strongly rubbing the eye. Rooms with dusty and smoky air should possibly be avoided.

Cornea Crosslinking is a method for mechanical stabilisation of tissue. In other medical fields such as orthopaedics, otorhinolaryngology, and cardiac surgery it has been applied for many years.

Crosslinking of the cornea is achieved by the combination of UV irradiation in combination with riboflavin eye drops (a derivate of vitamin B2). This leads to an increased number of cross-links between the parallel corneal fibres.  It is like a net that with additional struts gains mechanical stability. The energy level of UV rays is such that is does not affect the eye-structure under the cornea. 

It is an out-patient surgery of about 45 minutes with local anaesthesia. In a first step the superficial cell layer, the epithelium, is removed so that the riboflavin (Vitamin B2) can penetrate the cornea. Once the cornea is saturated with the riboflavin, it is irradiated for 10 minutes with UV light. The UV radiation of the riboflavin leads to a new cross-linking and a reinforcement of the corneal fibres. After the laser treatment an ointment contact lens is placed into the eye for 3-4 days until the corneal epithelium has healed naturally.

To improve the unevenness of the cornea the CXL method can be combined either with the implantation of ICRS or a superficial laser treatment (LASEK/PRK).   

To strengthen the cornea and to improve the visual acuity after approximately 4 weeks a rigid contact lens can be fitted.

ICRS, intracorneal ring segments, are a unique option to improve the visual acuity and in most cases postpone a transplantation of the cornea. This method was developed for patients in need of a correction of short-sightedness as well as of astigmatism (corneal curvature) with keratoconus when contact lenses or glasses do not offer any possibility of improvement.

The intracorneal ring segments are semi-circular Plexiglas rings which are introduced into the corneal tissue (stroma). In a first step the Femtoseconds laser in a gentle and precise way forms a pocket into which one or two synthetic half-rings are introduced. The patented design of the ICRS remodels the architecture of the cornea to restore its natural form.

Aim of this procedure is to improve the vision capacity of keratoconus patients with the help of glasses or contact lenses. In the few cases of ICRS patients where satisfactory vision improvement could not be achieved a later corneal transplant surgery was carried out without additional complications.

Both treatments are out-patient treatments. For optimal results these methods – (CCL and ICRS) can be combined so that not only a stiffening of the cornea but also an improvement of sight can be achieved.