CAIRS Treatment: Corneal Allogenic Intrastromal Ring Segments

What is CAIRS treatment?

Corneal Allogenic Intrastromal Ring Segments (CAIRS) is a treatment designed to improve the shape of the cornea in people with conditions such as keratoconus. The procedure uses specially prepared segments of donor corneal tissue that are placed within the cornea to help reduce irregularity and improve the way light is focused into the eye.

Keratoconus causes the normally round cornea to become thinner and develop a cone-like shape. This can distort vision and make everyday activities more difficult. CAIRS aims to support a more regular corneal shape while preserving the patient's own corneal tissue.

How does CAIRS work for keratoconus?

During CAIRS surgery, semi-circular or ring-shaped segments made from human donor corneal tissue are inserted into the middle layer of the cornea, known as the corneal stroma. Their position is planned according to the individual shape and characteristics of the patient's cornea.

By altering the corneal shape, CAIRS can help reduce the irregular cone associated with keratoconus. The aim is to improve visual quality and reduce distortion, although the degree of improvement varies from person to person.

What are the potential benefits of CAIRS?

Tissue-preserving approach

CAIRS preserves much of the patient's natural corneal tissue and may be considered as an alternative to more invasive corneal procedures in suitable patients.

Potential improvement in vision

Reshaping the cornea may improve visual acuity and reduce some of the distortion caused by keratoconus.

Personalised treatment

The position and configuration of the donor tissue segments can be planned according to the patient's individual corneal anatomy.

Potential future flexibility

Because the procedure involves implanted corneal tissue segments, future adjustments or additional treatment may be considered if clinically appropriate.

What happens during the CAIRS procedure?

1. Comprehensive eye assessment

Your ophthalmologist performs a detailed eye examination to assess your corneal shape, corneal health and vision, and to determine whether CAIRS may be suitable.

2. Donor tissue preparation

The allogenic corneal tissue is sourced from human donors and undergoes screening to help ensure its safety and suitability for implantation.

3. Anaesthesia

The procedure is typically performed using local anaesthesia to numb the eye. Sedation may also be used in some cases.

4. Corneal channel and implantation

A small opening is created and the donor tissue segments are carefully placed within the corneal stroma at a planned depth and position.

5. Customised positioning

The surgeon tailors the placement of the segments to the individual corneal shape, including the location and degree of corneal thinning and cone formation.

6. Post-operative care

After surgery, you will receive instructions about prescribed eye drops, activity restrictions and follow-up visits.

7. Monitoring and recovery

Your ophthalmologist will monitor healing and changes in corneal shape and vision. Recovery time varies, and visual improvement may develop over the days and weeks following treatment.

Is CAIRS suitable for everyone with keratoconus?

CAIRS is not suitable for every person with keratoconus. Suitability depends on the individual corneal shape, degree of thinning, overall eye health and the goals of treatment. A comprehensive assessment with an ophthalmologist is required to determine whether CAIRS is an appropriate option.

What are the risks of CAIRS?

As with any eye procedure, CAIRS has potential risks and complications. These may include an immunological response to the donor tissue. Your ophthalmologist should discuss the potential benefits, limitations and risks with you before treatment so you can make an informed decision.

CAIRS recovery and follow-up

Recovery varies between patients. Many people recover more quickly than they would after more invasive corneal procedures, but vision may continue to change as the cornea heals. Follow-up appointments are important so your ophthalmologist can monitor the position of the segments, corneal shape and visual outcome.

Speak with an ophthalmologist about CAIRS

If you have keratoconus and would like to understand whether CAIRS may be suitable for you, the next step is a comprehensive corneal assessment. An ophthalmologist can review your corneal shape, eye health and treatment goals and discuss the options available to you.