CAIRS Surgery: A Breakthrough Treatment of Progressive Eye Condition Keratoconus

WORDS LIM TECK CHOON

FEATURED EXPERT DR AINUR RAHMAN DATO SETIA DR ANUAR MASDUKI Consultant Ophthalmologist and Corneal Surgeon Ara Damansara Medical Centre

Keratoconus is a progressive eye condition that can significantly impact quality of life.

WHAT IS KERATOCONUS?

• Keratoconus is characterized by the thinning and bulging of the cornea, the clear front surface of the eye.
• This abnormal shape distorts vision because light rays entering the eye fail to focus properly on the retina.
• Symptoms include blurred or double vision, increased sensitivity to light, and difficulties in seeing at night.
• The condition often begins in the teenage years or early adulthood and can worsen over time, leading to significant visual impairment.

An Underdiagnosed Condition

Dr Ainur Rahman reveals that people with keratoconus are usually sensitive to glare or light, and when they check their vision, it often appears normal.

Because of this, many mistakenly believe they need better spectacles rather than realizing they have an underlying issue.

He advises those with possible symptoms of keratoconus to consult an ophthalmologist as soon as possible, as early diagnosis can lead to better treatment outcomes.

Who Is Most at Risk?

Certain factors increase the likelihood of developing keratoconus:

• A family history of keratoconus is a strong risk factor.
• Presence of medical conditions linked to this disease, such as asthma, Down syndrome, and Marfan syndrome.
• Frequent eye rubbing, which can worsen the condition.

Keratoconus affects both genders equally but is most commonly diagnosed between the ages of 10 and 25.

CONVENTIONAL TREATMENTS MAY OFFER ONLY LIMITED RELIEF

Treatment options for keratoconus have historically been limited.

• Early stages. Glasses or soft contact lenses may help.
• Advanced stages. Rigid gas permeable (RGP) lenses or surgical options like corneal cross-linking and transplants.

These approaches come with drawbacks:

• Glasses and soft lenses may fail to correct vision as the condition progresses.
• RGP lenses can be uncomfortable and poorly fitted to an irregular cornea.
• Corneal transplants carry risks such as rejection and long recovery periods.

CAIRS SURGERY: THE GAME-CHANGER

Recent advancements have introduced corneal allogenic intrastromal ring segment (CAIRS) surgery as a promising solution.

“CAIRS represents a breakthrough in our ability to treat keratoconus. We are not only providing a new treatment option but also offering hope to patients who may have been told that nothing more could be done for their condition,” explains Dr Ainur Rahman.

He adds that CAIRS is a safer and more effective option than conventional laser eye surgery, as the latter isn’t suitable for keratoconus patients due to their weaker and thinner corneas.

The first CAIRS surgery in Malaysia as well as Southeast Asia was successfully performed in July 2024.

How CAIRS Surgery Works

This minimally invasive procedure involves:

• Implanting specially designed ring segments made of donor corneal tissue into the stroma, which is the middle layer of the cornea.
• These ring segments reshape the cornea and improve vision, offering a more sustainable alternative to other treatments.

Generally, the procedure is as follows:

1. Performed under local anesthesia.
2. The surgeon creates tiny openings in the cornea.
3. The sterilized ring segments are implanted into the corneal stroma.
4. The cone-shaped cornea is flattened, enhancing its optical properties.

This procedure does not remove any tissue and is reversible if adjustments are needed.

Benefits

The benefits of CAIRS surgery include:

• Improved vision. Many patients experience better visual acuity and reduced reliance on glasses or contact lenses.
• Lower rejection risk. The use of sterilized donor tissue minimizes complications.
• Ring segments can be removed or adjusted if necessary.

Potential Drawbacks

While promising, CAIRS surgery is not without some drawbacks.

• Infection and healing complications, as with any surgery.
• Some patients may experience discomfort or vision changes, requiring further intervention.
• Limited availability of donor corneas.
• Long-term efficacy? More studies are needed to confirm the long-term success of the procedure.

A BRIGHTER FUTURE FOR KERATOCONUS PATIENTS

Keratoconus can be a challenging condition, but innovations like CAIRS surgery are paving the way for improved outcomes.

As research continues, people living with this condition have more reasons to be optimistic about managing their condition and enhancing their quality of life.