# Corneal Ring Implantation

Source page: https://www.kudretgozistanbul.com/en/treatments/corneal-ring-implantation

**Author:** Kudret Eye İstanbul | **Medical Approval:** Op. Dr. Mehmet Ali Özdil | **Date:** 2026-09-14

> **Summary:** Corneal ring implantation places thin, transparent semicircular ring segments into a femtosecond laser tunnel inside the cornea to improve its shape, mainly in keratoconus. The rings cannot be seen or felt, are placed outside the visual centre, and can be removed or exchanged by the doctor if needed.

## Quick Facts
- **Operation duration:** about 10-15 minutes per eye; the laser tunnel itself takes about 15 seconds
- **Anaesthesia:** local anaesthesia with drops, no stitches
- **Discharge:** home the same day, first check-up the following day
- **Recovery:** no restrictions on daily life; drops for a few weeks; possible pain or discomfort in the first 48 hours
- **Reversibility:** rings can be removed or exchanged; the cornea largely returns to its previous shape

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## What It Is
Ring segments of different thicknesses are chosen according to the degree of keratoconus. The aim is to return the central cornea to a more normal anatomical shape. The procedure has 2 stages: the femtosecond laser opens a tunnel at a depth set by measurements, then the rings are inserted. No corneal tissue is removed, which sets it apart from methods that remove tissue.

## Who It Suits
- Corneas irregular enough that glasses no longer give useful vision, in patients who cannot tolerate rigid contact lenses.
- Mostly keratoconus; also corneal ectasia, irregular corneal curvature and, less often, irregularities after laser surgery.
- Patients unsuitable for laser treatment or not helped enough by glasses and contact lenses.
- The cornea must be above a certain thickness and still clear; if it has lost clarity, other methods are assessed.

**May not be suitable:** advanced keratoconus, very thin corneas, severe corneal scars.

## Relation to Crosslinking
The ring corrects corneal shape to improve vision; crosslinking does not change the shape but halts disease progression. In progressing keratoconus they are often planned together: progression is stopped first, then vision is corrected, with order and timing set by measurements.

## Prices
The price depends on the underlying cause and the operation; the plan is set after a detailed examination.

## Risks and Possible Side Effects
- **Infection:** very rare; prevented with prescribed drops and hygiene.
- **Halos and glare at night:** may be noticeable in the first weeks, usually fade.
- **Less correction than expected:** topped up with glasses or contact lenses, or the ring exchanged.
- **Ring shifting or moving towards the surface:** uncommon; repositioned or removed.

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## The Treatment Journey

### Before Treatment
- Examination measures corneal thickness and structure, prescription and eye pressure.
- Stop contact lenses before the examination: soft lenses 5 days, hard (rigid) lenses 2 weeks beforehand.
- Do not take aspirin-style blood thinners within 3 days before treatment; other medications (blood pressure, diabetes) can continue.

### During Treatment
- Drops anaesthetise the eye; the laser creates the channel and the rings are placed.

### After Treatment
- Pain or discomfort possible in the first 48 hours; blurred vision, watering or light sensitivity are normal and decrease day by day.
- Use drops for a few weeks and attend check-ups as advised.

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## Frequently Asked Questions

**Q: In which cases is a corneal ring used?**
A: Keratoconus, corneal ectasia and irregular corneal curvature, especially when laser is unsuitable or glasses and contact lenses do not help enough.

**Q: Is a corneal ring permanent?**
A: It is placed permanently but can be removed or replaced if necessary.

**Q: Who cannot have a corneal ring?**
A: It may not suit advanced keratoconus, very thin corneas or severe corneal scars; suitability is decided after examination.

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## References
- Keratoconus, EyeWiki (AAO)
- Corneal implants for keratoconus (IPG227), NICE