The cornea is a clear, dome-shaped front window of the eye, which normally focuses light allowing you to see clearly. It also acts as protection to the eye from foreign bodies.
There are a few common corneal conditions, which include:
A scratch on the cornea is usually caused from a physical injury or foreign body. This can cause a gritty sensation in the eye, pain, redness, light sensitivity and weeping. It is important that you do not try to remove a foreign body from your eye on your own, you should seek medical assistance. If your ophthalmologist is not available, go directly to emergency at your nearest hospital. Foreign bodies or physical injuries to the cornea can cause infection and therefore it is important to seek specialist advice as soon as you feel any symptoms.
Keratitis is the inflammation of the cornea, which can be caused by an infection or by an injury to the cornea, a foreign body in the eye or even wearing contact lenses for too long. Symptoms of keratitis include; moderate to severe pain, redness, blurred or decreased vision, difficulty opening the eye, a gritty feeling and sensitivity to light. If you experience any of these symptoms, you require urgent attention.
Ocular herpes is a type of keratitis that occurs due to the herpes simplex virus (HSV). There is no cure for this; however, management and treatment of the infection is available to control future outbreaks.
Parts of the cornea lose clarity due to an accumulation of foreign material in one more layers of the cornea. It causes progressive vision loss, sometimes pain or even no symptoms.
There are may types of corneal dystrophies, including:
Keratoconus: The cornea becomes progressively thinner and protrudes, causing distortion of your vision. To find out more about keratoconus, click here
Fuchs' dystrophy: This is categorised by swelling up and thickening of the cornea due to the endothelial cells not functioning correctly any more. Symptoms include blurry vision, which is usually worse in the mornings, glare and halos, cloudy corneas and sensitivity to light.
Lattice dystrophy: It causes material to build up on the cornea in a lattice (grid) pattern, causing corneal erosion. This can cause pain in the eye, a foreign body sensation, blurry vision, watery eyes and light sensitivity. It usually begins in childhood and treatment includes eye drops, ointments and special eye patches and contact lenses. If there is severe scarring on the cornea, laser or a corneal transplant may be required.
Corneal ulcer: A corneal ulcer occurs when an open wound on the cornea becomes infected, usually by bacteria. It can lead to a loss of vision, therefore it is very important that it is treated early.
Pterygium: This is also known as surfer's eye. A pterygium is a growth on the conjunctiva (the mucous membrane on the front of the eye) that is non-cancerous but can spread onto the cornea. It appears as an elevated wedge-shaped bump on the eyeball, usually on the side closest to your nose. Most patients are asymptomatic; however, some may have blurry vision and discomfort.
The primary cause is UV light, hence long exposure to the sun tends to bring about a pterygium.
Treatment can be as simple as lubricating drops and sometimes steroid drops if it becomes irritated/inflamed. It can be excised by your opthalmologist, usually when it begins to enroach on the cornea, or symptoms are very bothersome. Otherwise, it can be excised purely for cosmetic reasons