Pterygium

**Definition:** An abnormal triangular fold of membrane in the interpalpebral fissure, extending from the conjunctiva to the cornea, being immovably united to the cornea at its apex, firmly attached to the sclera throughout its middle portion, and merged with the conjunctiva at its base. (Dorland, 27th ed)

**Tree numbers:** - C11.187.781

**Synonyms:** - Pterygium Of Conjunctiva And Cornea