J Korean Ophthalmol Soc.  1996 Oct;37(10):1614-1619.

Comparison of Refractive Change Measured by Corneal Topography between before and after Pterygium Excision

• Hong JW
• Lee TS

Abstract

Pterygium is known to cause corneal curvature changes by tractional effect on cornea. We measured central corneal curvature changes induced by pterygium and also evaluated topographic changes at the site of pterygium by difference map of corneal topography (Eyesys 2000, USA). Bedsides recurrent pterygium, we assessed keratomeric readings at central cornea(Sim K) and pterygium site in 20 cases of pterygium operated with bare sclera technique. Before operation, keratometric reading at 3mm central cornea(Sim K) was 43.71 +/- 1.12D in horizontal meridian, 44.94 +/- 1.41 D in vertical meridian and that of pterygium site was 40.92 +/- 3.28D. In the other hand, 4 weeks after pterygium excision. Sim K was 44.40 +/- 0.83D in horizantal meridian, 45.23 +/- 0.78D in vertical meridian and K reading of pterygium site was 44.45 +/- 1.51D. These results show that mean keratomeric changes of a pterygium site are greater than changes of mean Sim K(3.17 +/- 3.16D)0.61 +/- 0.43D). In conclusion, pterygium induced corneal astigmatism seems to be resulted from the peripheral flattening rather than the pterygium changes of central corneal curvature.

Keyword

Astigmatism; Keratometric reading; Pterygium; Topography

MeSH Terms

Astigmatism
Cornea
Corneal Topography*
Hand
Pterygium*
Reading
Sclera
Traction