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What is Progressive pterygium causes: and explain in detail?
Ans: c (Astigmatism) Ref: AK Khurana, 4th ed, p. 81Corneal astigmatism may occur in pterygium due to fibrosis in regressive stage.Pterygium:* Wing shaped fold of conjunctiva encroaching cornea from either side within the palpebral fissure* Degeneration & hyperplastic condition of conjunctiva* May be unilateral or bilateral, usually starts nasally (triangular fold of conjunctiva)* Symptoms-usually asymptomatic- Visual disturbance due to corneal astigmatism]- Diplopia* Psuedopterygium- Due to chemical bums* Treatment-Surgical excisionRecurrent recalcitrant pterygium - Surgical excision + lamellar keratectomy+lamellar keratoplasty