Corneal Allogenic Intrastromal Ring Segments (CAIRS) with Dr Daya Sharma

CAIRS surgery is a treatment option for selected patients with keratoconus or corneal ectasia. CAIRS stands for Corneal Allogenic Intrastromal Ring Segments. During this procedure, Dr Daya Sharma places carefully prepared donor corneal tissue segments inside the cornea to help improve its shape.

As a result, CAIRS may reduce irregular astigmatism and improve visual quality in suitable patients. However, it does not suit every eye. Therefore, a detailed corneal assessment is essential before Dr Daya Sharma recommends this treatment.

At Eye & Laser Surgeons in Sydney, Dr Daya Sharma assesses patients with keratoconus, post-LASIK ectasia, post-PRK ectasia, irregular astigmatism, and complex corneal shape problems. During the consultation, he reviews the corneal shape, corneal thickness, tear film, scarring, refraction, visual acuity, and overall eye health.

Importantly, CAIRS does not replace every keratoconus treatment. Instead, it forms one part of a broader keratoconus and corneal ectasia treatment pathway. Some patients may need corneal collagen cross-linking to stabilise the cornea. Others may benefit more from glasses, contact lenses, scleral lenses, topography-guided treatment, or corneal transplantation.

Because each eye behaves differently, Dr Daya Sharma recommends treatment only after reviewing the full clinical picture. This careful approach helps determine whether CAIRS surgery, cross-linking, or another option best supports long-term corneal health and visual function.

What Is CAIRS Surgery?

CAIRS stands for Corneal Allogenic Intrastromal Ring Segments. It uses small segments of donor corneal tissue to support and reshape the cornea.

In keratoconus, the cornea becomes thinner, weaker, and more irregular. Consequently, light entering the eye may scatter or focus poorly. This can cause blurred vision, ghosting, glare, halos, increasing astigmatism, and reduced vision quality.

During CAIRS surgery, Dr Daya Sharma creates precise channels inside the cornea. He then places donor corneal tissue segments into these channels. These tissue segments may help flatten the steepened cornea and improve its symmetry.

Unlike synthetic intracorneal ring segments, CAIRS uses human donor corneal tissue rather than plastic material. For this reason, many corneal specialists describe CAIRS as a tissue-addition procedure. However, suitability still depends on detailed measurements, corneal stability, and realistic visual goals.

What Conditions Can CAIRS Help Treat?

CAIRS may help selected patients with keratoconus or corneal ectasia, especially when the cornea has become irregular and glasses no longer provide clear, stable vision.

Dr Daya Sharma may assess CAIRS suitability for patients with:

Keratoconus
Post-LASIK ectasia
Post-PRK ectasia
Pellucid marginal degeneration
Irregular astigmatism from corneal ectasia
Poor visual quality despite glasses
Difficulty tolerating contact lenses
Selected cases where synthetic ring segments may not suit the eye

However, CAIRS is not a general replacement for glasses, contact lenses, corneal collagen cross-linking, or corneal transplantation. Instead, it may help selected patients within a broader corneal treatment plan.

For many patients, the first question is whether the cornea remains stable or continues to worsen. If keratoconus is progressing, Dr Daya Sharma may recommend corneal collagen cross-linking to strengthen the cornea and reduce the risk of further deterioration.

How Does Keratoconus Affect Vision?

Keratoconus changes the shape of the cornea. Instead of maintaining a smooth dome shape, the cornea gradually becomes thinner and more cone-like. As a result, light does not focus cleanly on the retina.

This irregular focus can cause:

Blurred vision
Ghosting or double images
Glare and halos
Increasing astigmatism
Frequent prescription changes
Poor night vision
Reduced quality of vision even with glasses
Difficulty tolerating contact lenses

In early keratoconus, glasses or soft contact lenses may still provide useful vision. However, as the cornea becomes more irregular, patients may need rigid contact lenses, scleral lenses, cross-linking, CAIRS, or corneal transplantation.

How Does CAIRS Work?

CAIRS works by adding donor corneal tissue into the weakened or irregular cornea. During treatment, Dr Daya Sharma creates carefully planned channels within the cornea. He then places donor corneal tissue segments into these channels.

These tissue segments may help by:

Supporting the thinner area of the cornea
Flattening excessive corneal steepening
Reducing irregular astigmatism
Improving corneal symmetry
Improving how light focuses through the eye
Improving glasses or contact lens tolerance in selected cases

The goal is not to cure keratoconus. Rather, CAIRS aims to improve corneal shape and visual function while preserving future treatment options where possible.

Importantly, CAIRS does not reliably stop keratoconus progression by itself. Therefore, if the cornea continues to worsen, Dr Daya Sharma may recommend corneal collagen cross-linking as part of the treatment plan.

CAIRS and Corneal Cross-Linking: What Is the Difference?

CAIRS and Corneal collagen cross-linking treat keratoconus in different ways.

Cross-linking strengthens the cornea. Therefore, doctors mainly use it to slow or stop keratoconus progression.

CAIRS changes the shape of the cornea. In contrast, it does this by adding donor corneal tissue segments inside the cornea.

Because these treatments have different goals, some patients may need both. For example, a patient with progressive keratoconus may need cross-linking to stabilise the cornea. Later, CAIRS may help improve corneal shape and visual quality.

This distinction matters. CAIRS may improve the shape of the cornea, but it does not replace cross-linking when the cornea continues to progress. Therefore, Dr Daya Sharma checks corneal stability before deciding on the safest treatment plan.

Who May Be Suitable for CAIRS?

CAIRS may suit selected patients with keratoconus or corneal ectasia who have poor visual quality because of an irregular corneal shape. It may also help some patients who struggle with glasses or contact lenses.

You may be a potential candidate if you have:

Keratoconus with irregular astigmatism
Post-LASIK ectasia
Post-PRK ectasia
Poor vision with glasses
Difficulty tolerating contact lenses
Adequate corneal thickness
Limited central corneal scarring
Realistic expectations about the result
A stable cornea or a plan to manage progression

However, CAIRS does not suit every patient. For example, patients with severe scarring, very advanced thinning, active inflammation, uncontrolled allergy, or ongoing eye rubbing may need a different approach.

Therefore, Dr Daya Sharma checks several factors before recommending CAIRS. These include corneal topography, tomography, corneal thickness, refraction, visual acuity, tear film quality, scarring, and signs of keratoconus progression.

Who May Not Be Suitable for CAIRS?

Some patients with keratoconus or ectasia need a different treatment pathway. In these cases, CAIRS may not provide enough benefit or may carry higher risk.

CAIRS may not suit patients with:

Severe central corneal scarring
Very advanced corneal thinning
Active eye infection
Active inflammation
Uncontrolled allergic eye disease
Ongoing eye rubbing
Unrealistic expectations
Corneal disease that is too advanced for tissue-addition treatment

In these situations, Dr Daya Sharma may recommend another option. These may include glasses, rigid contact lenses, scleral contact lenses, corneal collagen cross-linking, topography-guided PRK with cross-linking, implantable collamer lenses in selected stable cases, deep anterior lamellar keratoplasty, or corneal transplantation.

The best option depends on the cornea, the prescription, the patient’s symptoms, and the long-term health of the eye.

CAIRS Compared with Synthetic Ring Segments

Traditional intracorneal ring segments usually use synthetic plastic material. These segments can flatten the cornea and may improve vision in selected patients with keratoconus.

CAIRS uses donor corneal tissue instead. Because the implanted material is biological tissue, CAIRS may offer advantages in selected cases. However, it is not automatically better for every patient.

The choice between CAIRS, synthetic ring segments, cross-linking, contact lenses, or corneal transplantation depends on several factors. These include corneal shape, thickness, scarring, contact lens tolerance, visual goals, and long-term treatment planning.

Therefore, Dr Daya Sharma does not recommend CAIRS simply because it is newer. Instead, he considers whether it genuinely suits the patient’s eye.

What Happens During a CAIRS Assessment?

A CAIRS assessment with Dr Daya Sharma involves detailed testing to understand the structure, optics, and health of the eye. This helps determine whether CAIRS is appropriate, whether cross-linking is needed, or whether another treatment would be safer.

Your assessment may include:

Visual acuity testing
Refraction
Corneal topography
Corneal tomography
Corneal thickness mapping
Epithelial thickness analysis where available
Assessment for corneal scarring
Tear film and dry eye assessment
Pupil size assessment
Contact lens history
Keratoconus progression analysis
Discussion of lifestyle and visual goals

These tests help Dr Daya Sharma decide whether CAIRS is appropriate. In addition, they help determine whether corneal collagen cross-linking, contact lenses, topography-guided treatment, or corneal transplantation may provide a better option.

What Happens During CAIRS Surgery?

CAIRS usually takes place as a day procedure. The exact surgical plan depends on the patient’s corneal shape, treatment goals, and clinical findings.

First, Dr Daya Sharma’s team numbs the eye with anaesthetic drops. This helps keep the procedure as comfortable as possible.

Next, Dr Daya Sharma creates carefully planned channels inside the cornea. These channels match the planned position of the donor corneal tissue segments.

After that, Dr Daya Sharma places the donor corneal tissue segments into the channels. Once positioned, these segments help support and reshape the cornea.

Finally, he checks the position of the tissue segments and provides post-operative instructions. Patients then use prescribed eye drops to support healing and reduce inflammation.

Is CAIRS Painful?

Most patients have CAIRS with anaesthetic eye drops. During the procedure, patients may feel pressure or awareness around the eye. However, the anaesthetic drops help reduce discomfort.

After surgery, the eye may feel scratchy, watery, light-sensitive, or irritated. These symptoms usually reflect early healing. In addition, vision may fluctuate while the cornea settles.

Dr Daya Sharma provides post-operative instructions and eye drops to support recovery. Follow-up visits also help monitor healing, comfort, vision, and corneal shape.

Recovery After CAIRS Surgery

Recovery after CAIRS varies between patients. Some people notice early improvement in visual quality. Others take longer to stabilise.

During the early recovery period, vision may fluctuate. This can occur as the cornea heals, the tissue segments settle, and the tear film stabilises. Therefore, patients should not judge the final result too early.

Follow-up appointments play an important role after CAIRS surgery. At these visits, Dr Daya Sharma checks healing, segment position, corneal shape, inflammation, eye pressure, and vision.

In many cases, patients still need updated glasses or contact lenses after the cornea stabilises. However, the new corneal shape may allow these optical corrections to work better.

Benefits of CAIRS for Keratoconus and Ectasia

In suitable patients, CAIRS may help improve corneal shape and visual quality. However, the degree of improvement varies from person to person.

Possible benefits include:

Improved corneal shape
Reduced corneal steepness
Reduced irregular astigmatism
Improved visual quality
Improved glasses-corrected vision
Improved contact lens tolerance
Potential delay or reduction in the need for corneal transplantation in selected cases.

CAIRS should not be presented as a guaranteed way to remove the need for glasses or contact lenses.

Risks of CAIRS Surgery

All surgical procedures carry risks, and CAIRS is no exception. Although CAIRS may be helpful for selected patients, complications can occur.

Potential risks include:

Infection
Inflammation
Delayed healing
Segment movement or displacement
Corneal haze
Glare or halos
Under-correction or over-correction
Need for further treatment
Difficulty with contact lens fitting
Corneal scarring
Segment removal
Need for corneal transplantation in the future

Therefore, careful patient selection, sterile technique, post-operative monitoring, and realistic expectations are essential. Dr Daya Sharma will discuss the potential benefits, limitations, and risks before any treatment is recommended.

Is CAIRS a Corneal Transplant?

CAIRS uses donor corneal tissue and is a form of corneal transplant, but it is not the same as a full thickness corneal transplant (penetrating keratoplasty; PK), or DALK (deep anterior lamellar keratoplasty).

In CAIRS, small segments of donor corneal tissue are placed inside the patient’s own cornea. The central cornea is not replaced. By contrast, PK and DALK involve replacing a larger portion of the cornea and is usually reserved for more advanced disease, severe scarring, or cases where other options are unlikely to provide useful improvement.

CAIRS for Post-LASIK Ectasia

Post-LASIK ectasia is a rare but serious condition where the cornea becomes progressively weaker and more irregular after laser eye surgery. It can cause increasing astigmatism, blurred vision, ghosting, and reduced visual quality.

In selected cases, CAIRS may be considered as part of the treatment plan for post-LASIK ectasia. However, the first priority is to determine whether the cornea is stable or still progressing. If progression is present, corneal cross-linking may be needed to reduce the risk of further deterioration.

Why Choose Dr Daya Sharma for CAIRS Assessment in Sydney?

Dr Daya Sharma is a Sydney ophthalmologist with subspecialty expertise in corneal, cataract, refractive, and keratoconus surgery. At Eye & Laser Surgeons, Dr Daya Sharma assesses patients with keratoconus, post-laser ectasia, irregular astigmatism, and complex corneal shape problems using detailed corneal imaging and personalised treatment planning.

This is important because CAIRS is not a one-size-fits-all procedure. The decision must consider corneal shape, thickness, scarring, progression, visual goals, contact lens tolerance, and the possible need for corneal collagen cross-linking or corneal transplantation.

The aim is not simply to offer the newest procedure. Rather, the aim is to recommend the treatment option that best supports long-term corneal health and visual function.

Book a CAIRS and Keratoconus Assessment in Sydney

If you have keratoconus, corneal ectasia, post-LASIK ectasia, irregular astigmatism, or worsening corneal shape, a detailed assessment can help clarify your treatment options.

At Eye & Laser Surgeons, Dr Daya Sharma can assess whether CAIRS, corneal cross-linking, contact lenses, topography-guided treatment, or corneal transplantation may be most appropriate for your eyes.

Book a keratoconus and CAIRS assessment with Dr Daya Sharma in Sydney.

Eye and Laser Surgeons

Bondi Junction: (02) 9387 5300
Miranda: (02) 9531 5300
Email: reception@eyeandlaser.com.au

FAQ Section

What is CAIRS surgery?

CAIRS stands for Corneal Allogenic Intrastromal Ring Segments. It is a procedure where small segments of donor corneal tissue are placed inside the patient’s cornea to help improve corneal shape in selected cases of keratoconus or corneal ectasia.

Is CAIRS used for keratoconus?

Yes. CAIRS may be used in selected patients with keratoconus, especially when the cornea is irregular and visual quality is reduced. However, suitability depends on corneal shape, thickness, scarring, stability, and overall eye health.

Does CAIRS stop keratoconus from getting worse?

CAIRS is mainly designed to improve corneal shape. It does not reliably stop keratoconus progression on its own. Therefore, if keratoconus is progressing, corneal cross-linking may also be required.

Is CAIRS the same as corneal cross-linking?

No. Corneal cross-linking is designed to strengthen the cornea and reduce keratoconus progression. CAIRS is designed to improve corneal shape by adding donor corneal tissue segments.

Will I still need glasses or contact lenses after CAIRS?

Patients often need glasses or contact lenses after CAIRS. This is because the aim is usually to improve corneal shape and visual quality (reducing irregular astigmatism), rather than guaranteeing freedom from glasses or contact lenses.

Can CAIRS treat post-LASIK ectasia?

CAIRS may be considered for selected cases of post-LASIK ectasia. However, careful assessment is essential, and corneal cross-linking may be needed if the cornea is still progressing.

Who performs CAIRS assessment at Eye & Laser Surgeons?

Dr Daya Sharma assesses patients with keratoconus, corneal ectasia, irregular astigmatism, and complex corneal shape problems at Eye & Laser Surgeons in Sydney.