Cross-Linking is a technique used to "reinforce" the structure of the cornea affected by keratoconus by strengthening the links between the corneal collagen fibres.
These links are much slacker in keratoconus than in a normal cornea: this causes the pathological slippage of the corneal flap and the consequent erosion of the corneal geometry over time.
CROSS-LINKING, increases the number and strength of the links between the lamelle, and slows down corneal deformation over time.
The technique involves:
- Corneal epithelium removal
- The use of high concentration riboflavin eye drops (isotonic and hypotonic vitamin B2 depending on the minimum thickness of the cornea) which must penetrate into the surface and intermediate layers of the cornea
- The successive irradiation of the cornea with low dose UVA radiation for a pre-determined time period
- The insertion of a therapeutic contact lens for 2-4 days
- The use of antibiotic eye drops, anti-inflammatory drugs, lubricating eye drops for a few weeks and systemic painkillers for a few days
The results obtained may be assessed a few weeks after treatment.
In light of the excellent results obtained, evolutive keratoconus treatment is advisable, on average by the age of 40-45.
- Stabilisation of the shape of the cornea in almost all patients.
- Progressive reduction in corneal erosion for up to two years after the operation, with an improvement in the shape of the cornea and a consequent visual improvement in a high percentage of patients
- Almost complete absence of complications
Operations are now recommended in all cases from the age of 12 onwards, provided that the progression of keratoconus is documented (corneal tomography). The aim is to prevent progressive corneal erosion by reinforcing the structural tissue as early as possible, since this corneal tissue has so far not been greatly compromised, and therefore minimising visual damage.
In the one to three months after the operation it is possible to experience a slight reduction in visual acuity due to a transient increase in ectasia. After the third month, new links are created between the corneal lamellae and the structure has become more consolidated. At first the ectasia returns to pre-operative values and then in most cases is further reduced.