Treatment
CAIRS – Allogenic Corneal Rings (KeraNatural)
CAIRS uses sterilised human donor corneal rings (KeraNatural), implanted with a femtosecond laser, to reshape the cornea and improve vision in keratoconus — a minimally invasive, tissue-friendly alternative to corneal transplant.
FAQs
Frequently Asked Questions
A corneal transplant (keratoplasty) replaces all or part of the cornea with donor tissue and requires sutures that stay in for at least six months. CAIRS instead places small donor-tissue rings within the cornea to reshape it, without removing any of your own tissue. It is minimally invasive, has no sutures to remove, carries a lower risk of complications and has a much shorter recovery.
CAIRS is usually performed under topical anaesthesia (numbing drops). You are awake but should feel no pain. The surgeon creates a channel in the cornea — at our clinic using a femtosecond laser for precision — and places the donor rings within it. The procedure takes about 15 minutes, and most patients return to normal activities within a day or two.
The aim is to improve and stabilise vision and to reduce astigmatism as much as possible, but it is not possible to eliminate astigmatism entirely. Vision recovers gradually over several weeks or longer, and some patients still benefit from glasses or contact lenses afterwards.
KeraNatural/CAIRS is a newer procedure and is not reimbursed by most insurance companies, although corneal transplantation is generally recognised. Because CAIRS uses donated, transplanted corneal tissue, some insurers consider it in the same category as keratoplasty. We will discuss fees and any insurance questions at your consultation.
We advise taking about a week off work, though visual recovery can take longer. Soft contact lenses can usually be resumed as normal once vision settles; a gas-permeable or hard lens may need around a month before it can be worn comfortably again. Your contact lens practitioner may need to be involved before resuming lens wear.
Pregnancy and breastfeeding are considered contraindications, as the effects of treatment in pregnancy — and of pregnancy on the result — are not known. If you become pregnant after treatment, there is no evidence that CAIRS affects pregnancy or any of the sight and scanning tests performed.
Quick Facts
Duration
Approximately 15 minutes per eye
Anaesthesia
Topical anaesthetic drops — no needle injection
Recovery
Most activities within 1-2 days; around a week off work; vision recovers over several weeks
Pain Level
Mild discomfort
Ready to Learn More?
Take our quick suitability quiz or book a consultation to discuss your options with your consultant.
Related
Understanding Your Condition
Learn more about the conditions this treatment addresses. Knowledge is the first step toward confident decision-making.
Take the Next Step
Book a consultation to discuss CAIRS – Allogenic Corneal Rings (KeraNatural) with your consultant. Transparent advice, no pressure, and a personalised plan for your vision.

