The aim of Corneal Cross-Linking (CCL) treatment is to strengthen the corneal structure and stop the progression of the disease.

Application of Riboflavin (vitamin B2) Eye Drops 

Prior to treatment, the eye is anesthetized with topical anesthetic drops. Following topical anesthetic eye drops, the corneal epithelium is removed mechanically using a blunt spatula. 2 drops of riboflavin solution are applied over the cornea without epithelium at 5-minute intervals for 30 minutes.

UV Light Application

After 30 minutes, the patient is placed under a biomicroscope. After the fluorescence of the riboflavin is observed in the anterior chamber, the patient is taken back to the operating room. The cornea is exposed to 370 nm UV light for 5-10 minutes at 4-5 cm distance, within a space of 7 mm. During UV application, 2 drops of riboflavin are applied once every 1 minute. At the end of this procedure, a bandage contact lens is applied to the eye, but the eye is not covered.

UV Cross-Linking (Cross Linking in the Molecular Level) Treatment

UV Cross-Linking can stop the progression of the keratoconus disease by using UVA light and riboflavin to impact the collagen molecules of the cornea thus increasing the biomechanical strengthening of the cornea.

Outcomes of CCL Operations

The first scientific study of Dünyagöz Hospitals regarding this topic was presented at the European Society of Cataract and Refractive Surgeons (ESCRS, 8–12 September 2007) in Stockholm and approved to be presented at the American Academy of Ophthalmology (AAO) Congress.

Pre-Operative Tests and Examinations

  • Level of vision with and without eyeglasses
  • Refractive error with and without eye drops
  • Corneal topography (Orbscan II, Oculus Topography)
  • Corneal thickness (Sonogage 50Hz)
  • Endothelial cell count (Specular Microscope, Conan)
  • Fundus examination

Dünyagöz Difference in CCL Treatment

The first CCL treatment in Turkey has been applied by Dünyagöz Hospitals. The first "Keratoconus Diagnosis and Treatment Center" has been established within Dünyagöz Hospitals. These centers are equipped with all the necessary devices related to the diagnosis and treatment of keratoconus.

Dünyagöz is the most experienced center in the field of CCL in Turkey. Dünyagöz Hospitals have performed the greatest number of CCL treatments until today (over 20,000). Collaborative works with IROC Clinic (Zurich, Switzerland with Prof. Seiler and his team) where CCL was invented and developed are still continuing.

An archive system is very important due to the importance of the follow-up in keratoconus disease. Dünyagöz Hospitals have patient-specific archiving.



Patients who cannot use contact lenses or for whom contact lenses are considered unsuitable may benefit from the intrastromal corneal ring insert procedure, provided that keratoconus is not at an advanced stage. Under local anesthesia, intracorneal rings (INTACS, Keraring, Ferrara) are inserted into the cornea through channels opened within seconds using Femtosecond Laser.

Intracorneal Rings Specifications:

  • Transparent,
  • Micro-dimensional,
  • In varying thickness depending on the diopter to be corrected,
  • Implanted in the corneal tissue of the eye,
  • In crescent form and composed of 2 parts.

These rings are not noticed from outside and most importantly, their presence is not felt, like contact lenses. The rings can be removed easily at any time and leave no permanent scar which may affect vision since they are not placed in the visual center. Rings with different thicknesses are implanted according to the stage of keratoconus.

When Intacs rings are inserted into the corneal tissue, they flatten the cornea and eliminate the coning of the cornea which is caused by keratoconus. Myopia is also corrected with this procedure.

The ring implanted in the eye is clear and made of a material which is compatible with ocular tissue, without causing any problems in its lifetime, and can also be removed when required. It cannot be seen from the outside after the surgery and its presence in the eye cannot be felt either.

What Types of Rings Are Available?

Currently, two types of rings are used worldwide:

INTACS (Addition Technology): These are hexagonal rings with a diameter of 7 mm.

KERARING / FERRARA RING (Mediphacos/AJO Company): These rings are in the shape of a triangular prism and have a diameter of 5 mm.

At Dünyagöz Hospitals, corneal ring treatment is used to improve quality of vision in keratoconus. While no publication has yet reported that ring implantation stops disease progression, one-year follow up of the patients who have received a ring implantation at Dünyagöz as of today showed that nearly 88% of the patients had no progression. Therefore, patient follow-up after surgery is essential. If any progression is seen, CCL treatment can be performed after the ring operation.



A 3-dimensional topographic map of the cornea is created, like a footprint, and a customized laser treatment is programmed for each patient.

Unlike full Wavefront therapy, this procedure involves assessing irregularities of the cornea's upper surface only.

Which Keratoconus Patients is TopoLaser Appropriate for?

• Patients unable to use contact lenses,

• Patients who have undergone cross-linking therapy after 6 months for better vision and correction of diopters,

• Patients whose corneal thickness will be at least 400 microns after laser,

• Keratoconus patients who have received a corneal transplant before and have poor vision due to high astigmatism.

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