The Prediction Of Change In Corneal Refractive Power After Pterygium Excision With Conjunctival Autograft
Published 2026 - 44th Congress of the ESCRS
Reference: PP23.03 | Type: Poster | DOI: 10.82333/wtvv-4t09
Authors: Dr Gyeongsoo Lim* 1 , Prof. Dr Moon Sun Jung 1
1Department of Ophthalmology,Chungbuk National University Hospital, Chungbuk National University College of Medicine,Cheongju,Korea, Republic Of
Purpose
To assess the relationship between the size of pterygium and change in corneal refractive power (ΔK) after pterygium surgery. The time to postoperative stabilization of corneal refractive power was also evaluated.
Setting
Department of Ophthalmology, Chungbuk National University Hospital,Chungbuk National University College of Medicine, Cheongju, Republic of Korea.
Methods
Seventy two eyes underwent primary pterygium excision with conjunctival autograft. Corneal refractive power was measured using auto-keratometer (AR7100, Topcon, Japan) and corneal topography (Pentacam, Oculus, Germany) preoperatively and at 1 and 3 months postoperatively. Parameters of pterygium size including extension, width and area ratio were measured from anterior segment photographs using FIJI software (ImageJ distribution; NIH, USA) after calibration to a 12.00 mm horizontal white-to-white diameter preoperatively. Correlation between parameters and ΔK were analyzed. Linear regression analysis was performed to derive the formula to predict changes of mean keratometry.
Results
Mean keratometry (Km) measured preoperatively and at 1 and 3 months postoperatively were as follows: with auto-keratometer, 42.85±1.66 diopter (D), 43.60±1.47D and 43.58±1.69D with corneal topography, 42.02± 1.93D, 43.97±1.65D and 43.93±1.66D. The Km was significantly increased at each 1 and 3 months after surgery (p<0.001), but there were no difference between 1 and 3 months after surgery. Among parameters of pterygium size, the area ratio of pterygium showed the best correlation with mean ΔK (Pearson correlation coefficient r=0.70, p<0.01). We could predict mean ΔK with the area ratio of pterygium by formula “Mean ΔK = 0.171 x area ratio(%) – 0.402” (linear regression, R2=0.49, p<0.01).
Conclusions
The corneal refractive power stabilized 1 month after pterygium excision. The area ratio of pterygium is a useful predictor of postoperative ΔK and may assist intraocular lens power selection in combined cataract and pterygium surgery.