EC Ophthalmology

Research Article Volume 15 Issue 2 - 2024

Assessment of the Biomechanical Properties of the Cornea and Biomechanically Corrected Intraocular Pressure Under Different Levels of Intraocular Pressure in Healthy Individuals and Primary Open-Angle Glaucoma Patients

Marcelo Macedo1*, Remo Susanna Jr1, Wilma Lelis Barboza1, Renato Ambrósio Jr2 and Marcelo Hatanaka1

1Department of Ophthalmology, University of São Paulo, São Paulo, Brazil
2Department of Ophthalmology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil

*Corresponding Author: Marcelo Macedo, Department of Ophthalmology, University of São Paulo, São Paulo, Brazil.
Received: December 07, 2023; Published: January 19, 2024




Purpose: The study sought to analyze the intraocular pressure (IOP) dynamics as documented by the Corvis ST (CST), delving into the range of IOP fluctuations triggered by the water drink test (WDT) and juxtaposing these findings directly with Goldmann applanation tonometry (GAT) measurements. Simultaneously, the research aimed to probe into the corneal biomechanical characteristics portrayed by the CST amidst these varying IOP scenarios.

Methods: In a longitudinal, prospective study, IOP and corneal biomechanics were evaluated. Utilizing the CST, IOP dynamics induced by the WDT were juxtaposed with GAT measurements to discern the biomechanical disparities amidst varying IOP levels.

Results: 59 participants aged between 43 and 86 (59,97 ± 11,17) were evaluated. A consistent increase in IOP post-WDT was evident across all participants (p < 0.0001). There was no statistically significant difference between the baseline and peak measurements obtained with different IOP measurement techniques. Biomechanical parameters, specifically V1 (Applanation 1 velocity), V2 (Applanation 2 velocity), DA (Deflection amplitude) and SP-A1 (Stiffness parameter at first applanation), exhibited significant alterations post-WDT (p < 0.0001), especially when contrasting healthy individuals with primary open-angle glaucoma (POAG) patients. The measurements from CST bore a strong correlation with the GAT readings across both groups.

Conclusion: Our research accentuates the intricate interplay between corneal biomechanics and IOP. Notable shifts in corneal biomechanics, especially in parameters like V1, V2, DA and SP-A1, were observed in response to IOP variations induced by WDT, suggesting the corneal biomechanical structure's sensitivity to even transient IOP changes.

 Keywords: Corneal Biomechanics; Intraocular Pressure; Goldmann Applanation Tonometry; Scheimpflug Dynamic Analyzer; Primary Open-Angle Glaucoma; Water Drink Test

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Marcelo Macedo., et al. "Assessment of the Biomechanical Properties of the Cornea and Biomechanically Corrected Intraocular Pressure Under Different Levels of Intraocular Pressure in Healthy Individuals and Primary Open-Angle Glaucoma Patients." EC Ophthalmology 15.2 (2024): 01-11.

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