AIM: To investigate the relationship between pterygium size and corneal astigmatism.

METHODS: Totally 64 patients 70 eyes with primary pterygium were included in present study. Uncorrected visual acuity, corneal curvature and the length pterygium invading the cornea was measured. The association between length pterygium invading the cornea and the corneal astigmatism was analyzed. The difference between pre- and post-operative corneal astigmatism were analyzed, as well as uncorrected visual acuity.

RESULTS: Before operation, various levels of astigmatism were found in 69 eyes. The degree of astigmatism was associated with the length pterygium invading the cornea, and regular astigmatism was the main type. The degree of astigmatism reduced 1 month post-operatively and uncorrected vision acuity improved.

CONCLUSION:Pterygium would cause regular astigmatism, and the degree of astigmatism was significantly associated with the length pterygium invading the cornea. The operation of pterygium could obviously improve corneal astigmatism and visual acuity.