Crosslinking / Keratoconus

Keratoconus is a non-inflammatory, degenerative disease of the cornea that is characterized by its progressive thinning and weakening. As a result of thinning, the normal spherical shape of the cornea is distorted and results in a significant visual dysfunction.

It has an incidence of 1 case per 2000 people, usually affects both eyes (over 90% of cases), begins at the age of 10 to 25 years and generally progresses between the ages of 10 and 40 years.

There is also a keratoconus secondary to refractive laser interventions for the correction of myopia or myopic astigmatism (or postoperative corneal ectasia) that may begin a few years after surgery in patients with thinner corneas who underwent laser surgery or in patients with posterior or sub-clinical keratoconus that could not be identified prior to surgery.

In the primary keratoconus, at first there is an irregularity of the corneal curvature, which will change its refractive power, causing a myopia or myopic astigmatism. Visual dysfunction is significant right from the onset of the disease, the patient complaining of blurred vision, slight distortion of images, increased sensitivity to light, blurred images at any distance, eye irritation. Continuous vision deteriorates irreversibly, which causes frequent change of glasses.

 

(Normal: The smooth surface of the cornea allows a clear image on the retina

Keratoconus: The light that penetrates the eyes through an irregular cornea in keratoconus creates a distorted and blurred image)

 

Keratoconus, especially in the early stages, can be difficult to diagnose.

The "Oculus Prim" Medical Center has all the modern devices (Oculus, Germany) for the early diagnosis of keratoconus.

■ corneal topography: irreplaceable technique both for the diagnosis of keratoconus (especially in the initial stages), but also for monitoring the progression of the disease. The keratoconus module uses an artificial algorithm to detect keratoconus based on the profile of the spatial thickness of the cornea and its quantification.

■ non-contact self-refracting kerato pachymetry: by a single examination we obtain the objective refraction, the keratometric and pachymetric values ​​(corneal thickness) of the eyeball. It is indispensable for the staging of the keratoconus and the establishment of therapeutic indications.

Treatment

There are several therapeutic methods that are applied depending on the stage of the disease: corneal cross-linking, intra-corneal rings, corneal transplantation.

■ In stage I, corneal cross-linking is recommended to stop the evolution of the disease, associated with the prescription of glasses and / or soft contact lenses.

■ In stages II-III in addition to the cross-linking intervention, it is recommended to prescribe hard-scleral contact lenses to improve vision. UV Cross-Linking (CXL) treatment: it is applied in all ophthalmic centers with modern equipment in the world.

The purpose of CXL is to stop the thinning of the cornea and stop the evolution of the disease. A special surgery is performed on the cornea, using type A ultraviolet (UV) light emitted by a special device - the latest generation Seiler lamp (Peschke CCL-Vario) and a special drug, in the form of drops, called riboflavin (Peschke TE ). This treatment promotes the formation of new connections between the collagen fibers of the cornea (cross-linking) with their elongation, leading to increased stiffness in the corneal structure. Thus, the cornea hardens and its deformation no longer occurs. Studies show that this technique reduces astigmatism and stops the progression of keratoconus. Its effect on the cornea can be seen from the 2nd month.

(Corneal topography before Cross-Linking           Corneal topography after Cross-Linking)

Within the “Oculus Prim” Medical Center, the Cross-Linking technique is performed through several methods:

 

Epi-off Cross-Linking- through this technique the corneal epithelium is removed, then the cornea is soaked in a special solution of riboflavin for 30 minutes. The ultraviolet radiation is then applied for 30 minutes, and at the end of the intervention a therapeutic contact lens that will be worn for a few weeks until the corneal epithelium is restored. This technique requires a longer period of time until the final result is obtained, because it is necessary the epithelium to be restored on a larger surface, with more unpleasant symptoms in the first days after surgery (pain, photophobia, eye discomfort, tearing). Corneal healing is slower, visual acuity becoming useful after 10 -14 days, and the final result can be considered after 2-3 months.

Epi-on Cross-Linking - in this technique a special riboflavin (Peschke TE) is used which has the ability to penetrate through the corneal epithelium, without the need of removing it. The technique is faster (20 minutes soaking in riboflavin and 5 minutes UV exposure), has the advantage of rapid recovery of visual acuity, has no discomfort, and the patient can resume activity a few hours after surgery.

Other indications of the Epi-On method:

1. Post-traumatic, infectious, herpetic, neurotrophic keratitis

2. Corneal, degenerative corneal dystrophies (Terrien, Salzmann)

3. Recurrent erosion of the cornea

4. Severe dry eye syndrome, Sjogren

Before UVX Epi-On                                                                              After UVX Epi-On       

The intervention has the role of stopping the evolution of the disease and maintaining the vision that, otherwise, would evolve towards decrease and even total absence. Visual recovery cannot always be predicted, but most of the time, after several years, a slight improvement in visual acuity has been noticed (10% recovery of visual acuity), which is why it is currently also recommended for stabilized keratoconuses.

At the “Oculus Prim” Medical Center, the Cross-Linking intervention is performed using the newest and most efficient existing technology in the world, with the shortest application time. In addition to this, the vast experience of our doctors, perfected through training courses abroad, which makes the surgery very easily borne by the patient, with very fast healing, without hospitalization or special postoperative measures.

Oculus Prim Medical Center is the official representative of IROC Company, the manufacturer of the Seiler lamp.

(Corneal topography before Cross-Linking          

Corneal topography after Cross-Linking)