Astigmatism and visual impairment in pterygium: affected eyes in Jos, Nigeria.

One hundred and forty one pterygium-affected and 50 control eyes were examined. It was found that in most of the pterygium-affected and control eyes (85.7% and 79.4% respectively) astigmatism was with-the-rule. It was also found that overall the degree of astigmatism was higher in pterygium-affected eyes (Av. 1.56D) than in control eyes (Av. 0.92D). The degree of astigmatism was much higher in recurrent pterygium eyes when considered separately (Av. 1.81D). Visual impairment in both pterygium-affected and control eyes was in most cases due to co-existing organic diseases. In the remaining pterygium eyes without other organic diseases, the visual impairment could not be correlated with the degree of astigmatism (r = 0.547).