- Vienna '18
- ESCRS Player
- On Demand
- ESCRS iLearn
- ESCRS YO's
First Author: J.Kim SOUTH KOREA
Co Author(s): H. Han D. Lee
Back to previous
To investigate the effect of pterygium size on the change of corneal topography and corneal Higher-Order Aberrations(HOAs) before and after excision.
Department of Ophthalmology, Ilsan Paik hospital, Inje University, Goyang, Korea
Fifty eyes of 46 patients who had underwent pterygium excision were divided into two groups by size and area of the pterygium (small pterygium group: size ?2.0mm or area ?7.0mm2, large pterygium group: size >2.0mm or area >7.0 mm2). We measured the size of the pterygium by performing the preoperative slit lamp examination and measured the area of the pterygium by using the Image J program. Corneal topographic images using Orbscan II(Bausch & Lomb, Berlin, Germany) and Corneal HOAs using wavefront aberrometer (KR-1W®, Hartmann-Shack aberrometer, Topcon inc., Japan) were evaluated before surgery and also monitored its change after excision at postoperative 1week, 1month and 3months.
Small pterygium group was comprised of 13eyes and 37eyes were included to large pterygium group. There were no statistically significant differences in BCVA between two groups before and 3months after excision. Preoperative simulated keratometry astigmatism, 3-mm irregularity and 5-mm irregularity of large pterygium group were statistically significantly high compared with those of small pterygium group (P<0.001, P<0.001 and P=0.001, respectively). In terms of the effect of pterygium excision, small pterygium group showed no difference in simulated keratometry astigmatism before and after excision. In large pterygium group, simulated keratometry astigmatism was statistically significantly decreased 1week, 1month and 3months after surgery (P=0.015, P=0.005 and P=0.002, respectively). Preoperative corneal HOAs values of large pterygium group were significantly higher than those of small pterygium group (4-mm optical zone Total: P<0.001; trefoil: P<0.001; coma: P=0.048, 6-mm optical zone Total: P<0.001; trefoil: P<0.001; coma: P=0.036) but values of spherical aberration were not different. In small pterygium group, Root Mean Square(RMS) values of corneal HOAs before and after excision was not different. In large pterygium group, RMS values of corneal total HOAs, trefoil, coma and Point Spread Function(PSF) in the 4-mm & 6-mm zone were statistically significantly decreased 1week, 1month and 3months after surgery respectively(P<0.05).
In case of concurrent pterygium and cataract, precedent pterygium excision before cataract surgery may be useful to improve visual quality and select precise IOL power especially in eyes with pterygium of larger than 2.0mm in size or 7.0 mm2 in area.