The cornea is the clear outer layer at the front of the eye that helps to focus incoming light so that you can see clearly.  It also shields the rest of your eye from dust, germs, and other harmful matter.

The cornea contains a highly organized group of cells and proteins and there are no blood vessels to nourish or protect it against infection. Instead, it receives its nourishment from the tears and aqueous humor fluid that fills the anterior chamber behind it.

Corneal tissue consists of five basic layers: epithelium, bowman’s layer, stroma, descemet’s membrane and endothelium. 

Common conditions affecting the cornea

There are several common conditions that affects the cornea including infections, degenerations and many other disorders that may arise mostly as a result of heredity.

  1. Conjunctivitis (Pink Eye)
    Conjunctivitis refers to inflammation of the thin, translucent tissue (the “conjunctiva”) that lines the white part of the eye. It is commonly caused by a viral infection, or less commonly, a bacterial infection. It can also be caused by an allergic reaction to certain allergens such as dust mites or pollen.

  2. Corneal Infections
    An infection of the transparent front part of the eyeball (the “cornea”) that allows light into the eye. Infections can be due to micro-organisms such as bacteria, fungus, parasites and viruses. Most corneal infections in Singapore are due to bacteria.

  3. Corneal Ulcers (Keratitis)
    A corneal ulcer typically occurs as a painful, red eye, with mild to severe eye discharge and reduced vision. Most cases of corneal ulcers are due to a bacteria infection that invades the cornea, often following an eye injury, trauma or other damage.

  4. Dry Eye Syndrome
    Dry eye syndrome occurs when you do not produce enough tears or when the composition of tears is abnormal and cannot adequately cover the surface of the eye.
    Click the link to learn more about the causes and symptoms of dry eyes.

  5. Pterygium
    A fleshy, triangular or wing-shaped growth of the eye. It usually occurs on the inner corner of the eye but can also appear on the outer corner. It is a slow-growing, benign lesion, and is mostly harmless. However, a pterygium may sometimes grow over the cornea. In rare cases, it can grow large enough to cover the central cornea and affect vision.

Tips and treatments available

Click on the links below to learn more about the conditions that affect the cornea, what you can do about it and pick up some practical tips on how to care for your contact lenses.

How to Relieve Red Eye

DMEK: A New and Improved Corneal Transplant Procedure

Corneal Disease: New Blood Test for Early Detection

Corneal Disease Symptoms: Symptoms, Risk Factors and Treatment

Pterygium: A Fleshy Growth in the Eye

Endothelial Keratoplasty and Emerging Therapies for Corneal Endothelial Disease

How to Care for Contact Lenses

Types of Contact Lens and How They Work

Tips to Care for Your Contact Lens

Misuse of Contact Lens Can Damage Your Cornea

Contact Lenses Risks

Dry Eyes? Plasma to the Rescue

Plasma Eye Drops for Severe Dry Eyes

SERI and Singapore Chung Hwa Medical Institution Conclude Study on Treating Dry Eyes with TCM

Cornea-Related Eye Conditions (Pterygium, Dry Eyes, Corneal Infection, Eye Infection) – Doctor Q&A

Your Contact Lenses and Eye Health – Doctor Q&A


Click the link to return to the eye care home page.

Ref: J22