The Effect of Pterygium on Corneal Biomechanical Properties Using Corvis ST

Authors

Tararat Hoopholerb, Thammasat University Hospital, Pathum Thani, Thailand
Kosol Kampitak, Thammasat University Hospital, Pathum Thani, Thailand AND Department of Ophthalmology, Faculty of Medicine, Thammasat University, Pathum Thani, ThailandFollow
Supinda Leeamornsiri, Thammasat University Hospital, Pathum Thani, Thailand AND Department of Ophthalmology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand
Suntaree Thitiwichienlert, Thammasat University Hospital, Pathum Thani, Thailand AND Department of Ophthalmology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand
Promporn Patarajierapun, Thammasat University Hospital, Pathum Thani, Thailand; Department of Ophthalmology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand AND Department of Ophthalmology, Chulabhorn International College of Medicine, Thammasat University, Pathum Thani, Thailand
Soyci Tiantanyatip, Thammasat University Hospital, Pathum Thani, Thailand; Department of Ophthalmology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand AND Department of Ophthalmology, Chulabhorn International College of Medicine, Thammasat University, Pathum Thani, Thailand

Abstract

Introduction: Pterygium is a growth of fibrovascular tissue that originates from the conjunctiva and extends onto the cornea. It can destroy the Bowman’s membrane layer and superficial stroma of the cornea. Therefore, pterygium may affect corneal biomechanical properties.

Objectives: To compare corneal biomechanical parameters using Corvis ST between eyes with and without pterygium in the same patient.

Methods: A prospective study was conducted on 27 participants (mean age 59.67 ± 12.06 years) with unilateral primary pterygium. Each subject underwent ocular examinations, and pterygium size was measured. Corvis ST (Oculus Optikgeräte GmbH, Wetzlar, Germany) was used to measure corneal biomechanical properties. The measurements of the eyes with pterygium and fellow eyes were compared to evaluate the effect of pterygium.

Results: In 27 cases, the data from Corvis ST showed a significant decrease in Deformation Amplitude, Deformation amplitude Ratio, Deflection amplitude and Ambrósio Relational Thickness horizontal between the eyes with pterygium and the fellow eye (p = 0.049, 0.006, 0.030 and 0.016, respectively). There was no significant difference (p > 0.05) between the two eyes in Integrated Radius, Stiffness Parameter at First Applanation, Peak Distance at Highest Concavity, Radius at Highest Concavity, and Stress-Strain Index. Significant correlation was found between the Ambrósio Relational Thickness horizontal in pterygium eyes and the horizontal size of the pterygium. (p < 0.05).

Conclusions: Primary pterygium can affect the biomechanics of the cornea as measured by Corvis ST. Thus, when using Corvis ST to diagnose various conditions, the potential impact of pterygium should be considered.

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Recommended Citation

Hoopholerb, Tararat; Kampitak, Kosol; Leeamornsiri, Supinda; Thitiwichienlert, Suntaree; Patarajierapun, Promporn; and Tiantanyatip, Soyci. 2025 The Effect of Pterygium on Corneal Biomechanical Properties Using Corvis ST. Asian Medical Journal and Alternative Medicine. 25, 3 (Dec. 2025 ), 38-42.
Available at: https://doi.org/10.70933/2773-9465.1267

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