Pterygium: It’s a growth of the conjunctiva, the thin membrane that covers the front of the eye, which extends over the cornea, the clear dome-like surface that covers the colored part of the eye (iris).

• Common ocular surface disorder.
• Triangular-shaped fibrous tissue growing under the conjunctiva.
• Can encroach onto the cornea.
• Most common site: nasal conjunctiva, but also seen on temporal conjunctiva.

Risk Factors:

• Exposure to dry, dusty conditions, especially in rural populations working in hot, dry, windy weather.
• Prolonged sun exposure, as UV radiation causes pterygium.
• Genetic predisposition can play a role.
• In India, prevalence ranges from 9.5% to 13%, more common in rural areas.
• More common in males due to outdoor work.

Nasal Location:

• Light passing through the cornea concentrates on the nasal conjunctiva.
• Nose shadow reduces the strength of light on the temporal conjunctiva.
• Longer eyelashes on the outside of the lid filter light falling on the temporal side.
• Natural tears flow from the temporal to the nasal side, carrying dust that irritates the nasal conjunctiva.

Causes:

• UV rays damage limbal stem cells.
• Damaged limbal stem cells activate tissue and blood vessel growth factors.
• This leads to pterygium formation with blood vessels.

Symptoms:

• Irritation.
• Excessive tearing.
• Foreign body sensation.
• Cosmetic concerns.
• Reduced vision if the cornea is encroached upon.
• Difficulty fitting contact lenses.

Types of Pterygium:

1. Progressive:

• Thick, fleshy, vascular.
• Progressively encroaches onto the cornea.

2. Atrophic:

• Thin, attenuated, poor vascularity.
• Stationary, doesn’t progress as aggressively.

Treatment:

• Surgical removal of the pterygium.
• Conjunctival auto graft placement (conjunctiva taken from the upper part of the eye).
• Medical treatment includes drops to alleviate symptoms.
• Untreated pterygium can lead to complications.