Corneal Biomechanics for Ocular Hypertension, Primary Open-Angle Glaucoma, and Amyloidotic Glaucoma: A Comparative Study by Corvis ST

Nisa Silva; André Ferreira; Pedro Manuel Baptista; Ana Figueiredo; Rita Reis; Isabel Sampaio; João Beirão; Riccardo Vinciguerra; Pedro Menéres; Maria João Menéres

doi:10.2147/OPTH.S350029

Corneal Biomechanics for Ocular Hypertension, Primary Open-Angle Glaucoma, and Amyloidotic Glaucoma: A Comparative Study by Corvis ST

Clin Ophthalmol. 2022 Jan 8:16:71-83. doi: 10.2147/OPTH.S350029. eCollection 2022.

Authors

Nisa Silva¹, André Ferreira^{1

2}, Pedro Manuel Baptista¹, Ana Figueiredo¹, Rita Reis¹, Isabel Sampaio¹, João Beirão^{1

3}, Riccardo Vinciguerra^{4

5}, Pedro Menéres^{1

3}, Maria João Menéres^{1

3}

Affiliations

¹ Ophthalmology Department, Centro Hospitalar Universitário do Porto, Porto, 4099-001, Portugal.
² Unit of Anatomy, Department of Biomedicine, Faculty of Medicine of University of Porto, Porto, 4200-319, Portugal.
³ Department of Ophthalmology, Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto, 4050-313, Portugal.
⁴ Ophthalmology Department, Humanitas San Pio X Hospital, Milan, Italy.
⁵ The School of Engineering, University of Liverpool, Liverpool, UK.

Abstract

Background: To evaluate biomechanical parameters of the cornea provided by Corvis ST in patients with ocular hypertension, primary open-angle glaucoma, and amyloidotic glaucoma and to compare with healthy controls.

Methods: This was a cross-sectional study of patients with ocular hypertension, primary open-angle glaucoma, and amyloidotic glaucoma that underwent Corvis ST imaging. Primary outcome was the comparison of corneal biomechanical parameters between study groups after adjusting for age, gender, Goldmann intraocular pressure (GAT-IOP), and prostaglandin analogues medication. Secondary outcome was the comparison of different IOP measurements in each group.

Results: One hundred and eighty-three eyes from 115 patients were included: 61 with primary open-angle glaucoma, 32 with amyloidotic glaucoma, 37 with ocular hypertension and 53 were healthy controls. Amyloidotic glaucoma group had smaller radius (p=0.025), lower deflection amplitude at highest concavity (p=0.019), and higher integrated radius (p=0.014) than controls. Ocular hypertension group had higher stiffness parameter at first applanation (p=0.043) than those with primary open-angle glaucoma, and higher stress-strain index (p=0.049) than those with amyloidotic glaucoma. Biomechanically corrected intraocular pressure was significantly lower than Goldmann intraocular pressure in group with primary open-angle glaucoma (p=0.005) and control group (p=0.013), and Goldmann intraocular pressure adjusted for pachymetry in group with primary open-angle glaucoma (p=0.01).

Conclusion: Eyes with amyloidotic glaucoma have more deformable corneas, while eyes with ocular hypertension have less deformable corneas. These findings may be linked to the susceptibility to glaucomatous damage and progression. There were significant differences between Goldmann applanation tonometry and biomechanically corrected intraocular ocular pressure provided by Corvis ST.

Keywords: Goldmann tonometry; amyloidosis; corneal biomechanics; glaucoma; ocular hypertension.

Grants and funding

The authors have no funding to declare.