The conjunctiva is the transparent membrane covering the white of the eye and the inner surface of the lids. Most growths that arise there are benign, but malignant types such as melanoma and squamous cell carcinoma also occur. The distinction is made by examination and, where needed, pathological study, and treatment rests on surgical removal.
Blepharitis is chronic inflammation of the eyelid margin. It causes crusting at the lash roots, redness and itching of the lid edge, lids sticking together in the morning and a dry, gritty eye. Regular lid hygiene is the foundation of treatment, with antibiotic and anti-inflammatory measures added when needed.
Symblepharon is an adhesion between the inner surface of the eyelid and the surface of the eye. It follows trauma, chemical burns, severe infections and certain autoimmune diseases, restricting eye movement and causing dryness and lid malposition. Treatment means dividing the adhesion and covering the bare surface with suitable tissue.
In a chemical eye injury the outcome is decided in the first minutes, not at the hospital door: rinse the eye with plenty of water for at least 15 to 20 minutes, never try to neutralise the substance, then have the eye examined. Alkalis penetrate deeper than acids, and severe cases may need amniotic membrane or limbal stem cell transplantation.
Allergic conjunctivitis is a hypersensitivity reaction of the conjunctiva to allergens such as pollen, house dust mites and animal dander. Itching is the leading symptom, with redness, watering and lid swelling alongside it. Avoiding the trigger, cold compresses and appropriate eye drops keep symptoms under control.
Dry eye develops when the tear film is either too scarce or of poor quality, leaving the ocular surface unprotected. It causes stinging, grittiness, burning and, paradoxically, watering. Treatment combines artificial tears, eyelid care and, in selected patients, punctal plugs that keep tears on the surface for longer.
Pterygium is a triangular, fleshy growth that spreads from the conjunctiva onto the cornea, often called surfer's eye. Long-term ultraviolet exposure is the main cause. Small quiet lesions are simply monitored, while progressive or vision-affecting ones are removed and covered with a conjunctival autograft taken from the patient's own eye.
The ocular surface is a single working unit made up of the cornea, the conjunctiva covering the white of the eye and the inner lids, the eyelid margin, and the tear film that coats them all. These parts work together: every blink spreads tears across the surface, the glands in the lid margin produce the oily layer that stops those tears evaporating, and the cornea and conjunctiva are protected beneath that thin film.
That interdependence is the key to understanding ocular surface disease. When one link fails, the others are affected, which is why a patient who comes complaining of dryness often has the real problem at the lid margin, and a patient who comes complaining of itching often has underlying dryness. It is the reason I assess the whole surface at the examination rather than the symptomatic part alone.
Ayşe Dolar Bilge MD, FEBOphth.
Ophthalmologist, Oculoplastic Surgery
English
