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Updated: Feb 12, 2026

Synthesis of Soft Polysiloxane-urea Elastomers for Intraocular Lens Application
Published on: March 8, 2019
Influence of soft contact lens material on corneal warpage: prevalence and time to resolution
Youssef Rayess1, Nicolas Arej2, Youssef Abdel Massih2
1Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon.
Objective:
Corneal warpage represents a reversible distortion of the corneal surface induced by soft contact lens (SCL) wear. The aim of the study is to assess the influence of SCL materials, age, wearing duration, cylindrical refraction, and spherical equivalence on the prevalence and time to resolution of corneal warpage.
Methods:
This is an interventional prospective study in which SCL wearers volunteered to remove their SCLs and underwent, on each visit, a corrected distance visual acuity and anterior and posterior segment evaluation, along with keratometry measurement and corneal topography. Visits were scheduled 30 minutes after SCL removal, on day 4, day 7, and then weekly after SCL removal until warpage resolution.
Results:
A total of 17 volunteers (34 eyes) were included, with 9 (18 eyes) in the hydrogel SCL group and 8 (16 eyes) in the silicone hydrogel SCL group. The difference in warpage prevalence between the hydrogel group (28%, 5 eyes) and silicone hydrogel group (31%, 5 eyes) was not statistically significant (p > 0.90). Duration necessary for warpage resolution ranged from 7 to 21 days with no statistically significant difference between the 2 groups (p = 0.12).
Conclusions:
Both types of SCL had similar corneal warpage prevalence and time to resolution, with slightly longer mean time to resolution with silicone hydrogel. All eyes had resolution of warpage by 3 weeks. It seems more cautious to wait longer than the usual 1-week interval before performing refractive surgery, especially in patients wearing SCL for long periods and regardless of the type of material.
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