Condition

Keratoconus, modern treatment.

Modern keratoconus care is additive-first. Reshape the cornea by adding tissue — not removing it — then stabilise, then refine the residual vision. The order matters.

What is keratoconus?

Keratoconus is a non-inflammatory corneal disorder in which the cornea progressively thins and steepens, producing irregular astigmatism, blurred vision and increasing distortion. It typically presents in the teenage years or early adulthood and is more common in patients who rub their eyes, have allergic disease, or have a family history of keratoconus.

An additive-first approach

It makes biological sense to add tissue to a thin, weak cornea rather than remove more tissue from the weakest part of it.

That principle drives the modern sequence. CAIRS implants donor corneal tissue to reshape the cone; cross-linking stabilises the new shape; an implantable contact lens or spectacles refine the residual prescription. The patient's own cornea stays intact — and every option remains open if the disease evolves.

The modern path

Reshape, stabilise, then refine.

A staged sequence built around the principle of adding before removing. Most patients today move through the first three steps and never need the fourth.

01

Reshape with CAIRS

Donor corneal tissue is implanted as ring segments inside the cornea, flattening the keratoconic cone. No patient cornea is removed; segments can be exchanged or removed later. The first procedural step in a modern plan.
How CAIRS works

Type

Additive
02

Stabilise with cross-linking

Riboflavin and UV-A light strengthen the corneal collagen, halting disease progression. Indicated when there is evidence the disease is still progressing — can be performed with CAIRS or as a separate step.

Type

Stabilising
03

Refine residual vision

Whatever residual refraction remains is addressed with whatever fits the eye — glasses (where many patients find their best quality of vision), soft contact lenses, scleral or rigid gas-permeable lenses for higher residual error, or an implantable contact lens (ICL) where the prescription is significant. Cataract or refractive lens surgery is offered when the patient is age-appropriate.

Type

Additive
04

Transplant — only if needed

Reserved for the small minority who progress despite the above. Modern lamellar techniques (DALK) preserve more of the patient's own tissue than older full-thickness grafts, and most patients today never reach this step.

Type

Last resort

Refinement options

What's left after the cornea is reshaped.

Once CAIRS has done the structural work and cross-linking has stabilised the result, the residual refractive error is usually modest. Most options remain on the table — sequenced from additive to selective.

Additive · refinement

Glasses & soft contact lenses

For most patients after CAIRS and cross-linking, the residual prescription is well-corrected by spectacles or soft contacts. Still has a central role.

Additive · refinement

Scleral & RGP lenses

For corneas that need a more rigid optical surface than soft lenses provide — particularly useful where some surface irregularity remains.

Additive · refinement

Implantable contact lens (ICL)

For higher residual prescriptions, or when the cornea is unsuitable for any other tissue-modifying procedure. Adds a lens inside the eye — does not remove tissue. Removable.

Additive · refinement

Cataract / refractive lens exchange

For age-appropriate patients, lens-based surgery refines vision precisely without further corneal intervention.

Stabilising

Corneal cross-linking

The stabilising step. Halts progression by strengthening corneal collagen. Indicated when there is evidence the disease is still progressing — can be performed with CAIRS or as a separate step.

Why the order matters

It makes biological sense to add tissue to a thin, weak cornea rather than remove more tissue from the weakest part of it. CAIRS-first preserves the patient's own cornea, leaves every later option open, and offers a procedure that can be exchanged or removed if the disease evolves.

Where the disease is still progressing, cross-linking can be added to CAIRS — at the same time, or as a separate step. The biomechanical logic is the same: stabilise the improved shape, not the shape the disease produced. Whatever residual refraction remains is then addressed with whatever fits the eye — glasses, soft or scleral contact lenses, or an ICL where the prescription is higher.

Brisbane and Australia

Dr David Gunn and Dr Brendan Cronin practise this additive-first approach at Focus Vision in Woolloongabba, Brisbane, alongside the Queensland Eye Institute. They were the first surgeons to perform CAIRS in Australia and continue to publish on outcomes and planning. For patient-facing information, see our patient guide to keratoconus.

Tools