Keratoconus: symptoms, causes and treatments

What is Keratoconus?

Keratoconus is a non-inflammatory condition where the cornea (the clear window at the front of the eye) changes shape and bulges outward. As the condition progresses, the back surface of the cornea can split, a complication known as acute corneal hydrops. The abnormal shape distorts the light entering the eye, causing distorted images to reach the brain.

Clinical features

Keratoconus typically affects both eyes, though the severity can differ between each eye. Opticians and optometrists may detect keratoconus by noticing an increase in astigmatism, which is irregular and cannot be fully corrected with glasses. In mild cases, vision may be adequately corrected with glasses, but more advanced cases often require special keratoconus contact lenses.

Symptoms

• Blurring and reduced vision quality: Difficulty with tasks such as driving and reading.
• Sensitivity to light: Increased sensitivity to bright light and ‘ghosting’ of images, especially at night.
• Frequent prescription changes: Frequent changes in lens prescription can indicate keratoconus.
• Eye irritation: Mild discomfort or irritation.

Keratoconus affects approximately 1 in 2000 Caucasian individuals and 1 in 500 Asian individuals.

Causes

The main cause of keratoconus is the weakness of the supporting collagen fibres in the cornea, making it structurally weak. It most commonly affects people in their teens through their early thirties and is more prevalent in individuals with Down’s Syndrome, asthma, or eczema. Both hereditary factors and environmental factors like eye rubbing and allergies contribute to the development of keratoconus.

Diagnosis

If you experience poor vision quality, consult your optician or contact us for an appointment. Keratoconus can be similar to astigmatism and is often detected during astigmatism consultations. The condition is diagnosed using advanced elevation-based Scheimpflug corneal topography, which also helps detect subclinical forms like forme fruste keratoconus. Regular check-ups are recommended for anyone diagnosed with this condition.

Treatment Options

Non-surgical treatments

• Glasses and contact lenses: Mild cases can be managed with glasses or special keratoconus contact lenses.
• Specialist contact lenses: Most cases can be corrected with these lenses, sometimes in combination with corneal surgery.

Surgical Treatments

• Accelerated corneal collagen crosslinking: This procedure, done under topical anaesthetic, uses riboflavin drops and ultraviolet light to strengthen the cornea. The procedure is quick, and a bandage contact lens is applied post-surgery.
• Intrastromal corneal rings (Kerarings): Custom-made plastic ring segments are inserted into the cornea to flatten it into a more normal shape, often reducing the need for contact lenses.
• Keranatural: Corneal Allogenic Intracorneal Ring Segments (CAIRS), unlike synthetic alternatives such as Intacs or Ferrara rings, Keranatural CAIRS uses human corneal collagen that has been processed to meet rigorous safety standards.
• EndoArt®: EndoArt® is a revolutionary synthetic corneal transplant designed for the treatment of corneal endothelial dysfunction, where a flexible artificial endothelial layer is used to replace the damaged endothelial cells in the cornea.
• Implantable collamer lens (Phakic IOL): This option is suitable for those who want freedom from glasses or contact lenses. The surgery is performed under local anaesthetic and has a short recovery time.
• Topography-guided excimer laser advanced surface ablation: In carefully selected patients, this laser procedure reshapes the cornea to improve vision and reduce stress on the cornea.
• Big-bubble selective deep anterior keratoplasty: This innovative procedure transplants only the diseased portion of the cornea, leaving the endothelial cell layer undisturbed and reducing the risk of rejection.

For more detailed information about the surgical procedures, please visit their specific pages.