What Is a Corneal Ring? Who Is Suitable for Intracorneal Ring Segments?

Eye health is essential for clear vision. A corneal ring, also called an intracorneal ring segment, is one of the surgical options used especially in corneal shape disorders such as keratoconus.

What Is a Corneal Ring?

Corneal rings are small semi-circular implants used to help regularize corneal shape abnormalities. They are placed inside the cornea to help adjust corneal curvature and improve visual quality.

They are most commonly considered in keratoconus. Keratoconus is a progressive corneal disease in which the cornea becomes thinner and bulges forward. Corneal rings aim to make the corneal shape more regular; however, separate treatments such as corneal cross-linking may be planned to slow or stop progression.

When Are Corneal Rings Used?

• Keratoconus: In suitable cases, corneal rings may help regularize corneal shape and improve visual quality.
• Irregular astigmatism: They may be considered in selected patients with visual quality problems caused by irregularities on the corneal surface.
• Corneal ectasia: In selected cases, they may be evaluated for corneal weakening and shape changes that can occur after some laser procedures.

Who Is Not Suitable for Corneal Rings?

Not every eye structure is suitable for corneal ring implantation. A detailed eye examination, corneal topography/tomography and corneal thickness assessment are required before the procedure.

• Advanced corneal damage or significant corneal scarring
• Active eye infection or inflammation
• Insufficient corneal thickness
• Ocular surface disease or uncontrolled dry eye
• Expectations that cannot realistically be met by the procedure

How Are Corneal Rings Implanted?

The procedure is usually performed with topical anesthesia, meaning anesthetic eye drops. In suitable patients, a special tunnel is created inside the cornea and one or two semi-circular ring segments are placed into this tunnel. The tunnel may be created with a surgical technique or femtosecond laser.

The aim is to make the central cornea more regular, reduce irregular astigmatism and support the visual quality that can be achieved with glasses or contact lenses. Results vary from person to person, so expectations should be discussed clearly with the physician before the procedure.

How Long Does the Corneal Ring Procedure Take?

The procedure is usually completed in a short time. As stated in the source text, it may take approximately 10-15 minutes, and the patient may be discharged the same day. Preparation, examination, eye drop application and postoperative control may extend the total visit time.

Recovery After Corneal Ring Implantation

• Mild stinging, tearing, light sensitivity and blurred vision may occur after the procedure.
• Many patients can return to daily life within a few days; however, eye rubbing should be avoided.
• Antibiotic, anti-inflammatory or lubricating eye drops prescribed by the physician should be used regularly.
• Visual stabilization may take several weeks, and regular eye follow-up is needed during this period.
• If pain, sudden decrease in vision, marked redness or discharge occurs, medical care should be sought promptly.

What Are the Advantages of Corneal Rings?

• May be reversible or exchangeable: Ring segments may be removed or replaced in suitable situations.
• Aims to reshape the cornea: It helps adjust corneal curvature without removing corneal tissue.
• May improve visual quality: In suitable keratoconus patients, it may reduce irregular astigmatism.
• May support contact lens tolerance: In some patients, regularizing corneal shape may make contact lens fitting easier.

Corneal rings, which aim to regularize corneal shape, can be an important option to improve visual quality in suitable patients. However, results are not the same for every patient, and they may need to be evaluated together with other treatments to slow keratoconus progression.

Frequently Asked Questions

References

1. Academic Hospital. Korneal Ring (Kornea İçi Halka) Nedir? Kimler İçin Uygundur?
2. American Academy of Ophthalmology EyeWiki. Keratoconus
3. Cleveland Clinic. Keratoconus: Symptoms, Causes & Treatment
4. Cochrane. Intrastromal corneal ring segments for keratoconus