Keratoconus

Definition:

Keratoconus is a progressive and uncommon eye disease characterized by thinning or weakening of the cornea that eventually bulges out into a cone-like shape. This cone shape deflects light entering in to the eye and result in distorted vision. It can occur in one or both eyes but eventually develops in both eyes, although not always to the same extent.

Risk factors of Keratoconus

There are certain factors that can increase a person’s chances of developing keratoconus. These include:

• Family history
• Certain allergic conditions like asthma, hay fever, eczema
• Down’s syndrome
• Some disorders of connective tissue such as Marfan’s disease
• Eye conditions like retinitis pigmentosa, retinopathy of prematurity or vernal keratoconjunctivitis
• Teens or early 20s

Causes of Keratoconus

The reasons that can lead to thinning or weakening of cornea may include:

• Imbalance of enzymes within the cornea
• Decreased protective antioxidants in the cornea
• Overexposure to ultraviolet rays
• Excessive and vigorous eye rubbing
• Ill fitted contact lenses
• Wearing contact lenses for several years
• Chronic eye irritation
• Chronic eye rubbing
• Genetic predisposition

Symptoms of Keratoconus

Keratoconus is a progressive disease that may keep on progressing for 10 years and may stop progression on its own. The signs and symptoms of keratoconus changes as the disease progresses and may include all or some of the following.

• Progressive near sightedness
• Irregular astigmatism
• Distorted and blurred vision
• Glare
• Light sensitivity
• Frequent changes in their eyeglass prescription
• Eye strain
• Multiple images
• Headaches and general eye pain
• Eye irritation
• Excessive eye rubbing
• Vision that cannot be corrected with glasses
• Difficultly driving at night
• Corneal scarring

Diagnosis of Keratoconus

Keratoconus is sometimes difficult to diagnose as most of its symptoms resemble various other eye diseases. A thorough examination of the eye by a competent eye doctor along with following examinations may help in establishing diagnosis of keratoconus:

• Slit lamp examination
• Keratometry
• Corneal topography
• Optical coherence tomography

Keratoconus Treatment

Mild keratoconus can be managed by eyeglasses or soft contact lenses but treatment for moderate and advanced keratoconus include:

• Custom soft contact lenses
• Gas permeable contact lenses
• “Piggybacking” contact lenses
• Hybrid contact lenses
• Scleral and semi-scleral lenses
• Intacs implants
• Corneal collagen crosslinking
• Topography-guided conductive keratoplasty
• Corneal transplant