Optimal Time for Stabilization of Anterior Corneal Keratometry after Primary Pterygium Excision Adjusted for Horizontal Invasion Length
- Author:
Seunghwan KIM
1
;
Seung Hyeun LEE
;
Kyoung Woo KIM
Author Information
- Publication Type:Original Article
- From:Korean Journal of Ophthalmology 2026;40(2):133-140
- CountryRepublic of Korea
- Language:English
-
Abstract:
Purpose:To determine the corneal stabilization timeline after pterygium excision adjusted for horizontal invasion length (HIL).
Methods:In this single-center retrospective cohort study, we analyzed 88 eyes of 80 patients with nasal or temporal primary pterygium who underwent excision and perioperative evaluation with anterior segment (AS) swept-source optical coherence tomography (SS-OCT; Anterion). Anterior simulated mean keratometry (SimKmean; 3-mm ring) and HIL were measured on AS SS-OCT. Keratometric stabilization was assessed at postoperative cutoffs of 8, 12, 16, 20, and 24 weeks using analysis of covariance (ANCOVA) with HIL as a covariate. Subgroup analysis was performed after stratifying by the median HIL (3.82 mm).
Results:Mean anterior SimKmean increased from 42.95 ± 1.79 diopters (D) preoperatively to 43.73 ± 1.53 D postoperatively (p < 0.001). Preoperative HIL correlated positively with the perioperative SimKmean change (r = 0.728, p < 0.001). While postoperative duration showed no significant unadjusted correlation with keratometric change (r = −0.133, p = 0.218), partial correlation controlling for HIL was negative (r = −0.248, p = 0.021), indicating diminishing change over time after severity adjustment. ANCOVA demonstrated significant stabilization at 16 weeks (p = 0.036). In the HIL ≥3.82 mm subgroup, SimKmean change was greater before 20 weeks than after 20 weeks (1.73 ± 1.59 D vs. 0.59 ± 0.74 D, p = 0.030), whereas no significant time-point differences were found for HIL <3.82 mm.
Conclusions:Corneal keratometric stabilization after pterygium excision depends on preoperative HIL. A minimum of 16 weeks is recommended before cataract surgery planning, with at least 20 weeks for eyes with HIL ≥3.82 mm.
