Intracorneal Ring Segments (ICRS)

What Are Intracorneal Ring Segments?

Intracorneal ring segments (ICRS) are small semicircular segments made of a biocompatible material that are inserted into the thickness of the cornea to reshape its curvature. They’re one of the key treatments for keratoconus: when the cornea has become distorted and vision can no longer be corrected well with glasses or contact lenses, the rings regularize it from within.

Once inserted into the periphery of the cornea, the segments flatten the central bulge caused by keratoconus, reducing irregular astigmatism and improving visual quality. They’re not visible to the naked eye, you won’t feel them, and no corneal tissue is removed to place them.

Why Femtosecond Laser?

The modern technique uses a femtosecond laser to create the tunnels that hold the rings. This is a major step up from the older manual technique:

• Micron-level precision in tunnel depth and position
• Greater safety: lower risk of perforation or misplacement
• More predictable, reproducible results
• Faster recovery than with the manual technique

Advantages Over Other Options

• Reversible and adjustable: they can be removed, repositioned, or swapped, unlike a transplant, which is permanent
• No tissue removed: the cornea stays intact for future options
• Minimally invasive: outpatient, with topical anesthesia
• Compatible with cross-linking: can be combined to stabilize and improve vision at the same time

Clinical Indications

Intracorneal ring segments are appropriate for patients with:

• Mild to moderate keratoconus that’s no longer well corrected with glasses
• Intolerance to rigid contact lenses due to corneal distortion
• Adequate corneal thickness in the implant area (confirmed by pachymetry)
• No significant central scarring on the cornea

Contraindications

The rings aren’t recommended when:

• Keratoconus is very advanced with severe thinning
• There’s central corneal scarring that limits vision
• The cornea is too thin in the tunnel area
• There are active eye infections

Step-by-Step Procedure

1. Pre-op evaluation: Pentacam corneal topography and pachymetry to plan the number, size, and position of the rings based on your specific corneal map.
2. Day of surgery: topical anesthesia with eye drops. Outpatient procedure.
3. Creating the tunnels: the femtosecond laser creates the intracorneal tunnels in seconds, with micron-level precision.
4. Inserting the segments: the surgeon places the rings through the tunnels, in the planned position.
5. Verification: correct positioning is confirmed.
6. Same-day discharge with post-op instructions and eye drops.

The procedure takes 15-20 minutes per eye.

Recovery and Aftercare

In the first few hours you may feel some foreign-body sensation, tearing, and light sensitivity, which ease with eye drops. Discomfort is milder than with cross-linking since the epithelium isn’t removed.

Visual recovery:

• Days 1-3: vision gradually clears
• Weeks 2-4: you reach 80-90% of the final improvement
• The cornea keeps adjusting for a few more weeks

During the first week, you’ll use antibiotic and anti-inflammatory eye drops, and avoid rubbing your eyes, swimming, and strenuous exercise.

Why Choose Centro Láser for Intracorneal Ring Segments

Centro Láser has a cornea department with four fellowship-trained specialists and femtosecond laser technology for precise ring placement. We plan every case with Pentacam topography to determine the optimal number, size, and position of the segments. We frequently combine the rings with cross-linking to stabilize keratoconus and improve vision as part of one integrated plan, all within the same center.