Crosslinking process (X-linking)

Crosslinking is a method of mechanical stabilization of tissues. This method has been used for several decades in other fields of medicine, but for the eye it was only developed in the 1990s. The therapeutic goal is to artificially increase collagen tissue, mechanical stability and corneal resistance. Treatment of the cornea occurs by a combination of UV radiation while administering riboflavin eye drops (vitamin B2 derivative). The duration of the UV radiation is determined by the corneal thickness, so that the eye structures below the cornea are not impaired. Indications: Crosslinking is used in the treatment of keratoconus. The aim is to stabilize the protrusion of the cornea and to counteract the progress of the keratoconus.


To optimize the outcome of the procedure, it is recommended that the patient visits a contact lens specialist who places an Ortho-K contact lens 5 days prior to the planned procedure and wear it until the day of treatment.


The operation is performed on an outpatient basis. It takes about 2 hours to prepare and is performed under local anesthesia. First, the outer layer of the cornea, the epithelium, is removed. This is necessary for the riboflavin to penetrate the cornea. After a half-hour drip treatment with the dye, the cornea is irradiated for a further 30 minutes with UV light. At the end of the procedure, a therapeutic protective contact lens is placed on the cornea. This remains on the eye for a few days and may only be removed by the attending ophthalmologist.


The procedure leaves part of the corneal surface open. This can be compared with the sensation and healing process experienced after contracting a small abrasive wound, e.g. as can happen on your knee after a fall. In the first few weeks after the treatment, the visual performance may fluctuate, the vision may initially be more blurred than before, and a stronger glare from bright light may occur. The use of artificial tear substitutes may also be required. All this is part of the normal healing process. After this phase and the resolution of postoperative symptoms, patients achieve the same or even better visual acuity than before surgery.