Original Article
Corneal Biomechanical Parameters and Asymmetric Visual Field Damage in Patients with Untreated Normal Tension Glaucoma Bai‑Bing Li1, Yu Cai1, Ying‑Zi Pan1, Mei Li1, Rong‑Hua Qiao2, Yuan Fang1, Tian Tian1 1
Department of Ophthalmology, Peking University First Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing 100034, China 2 Department of Ophthalmology, Beijing Tsinghua Changgung Hospital, Beijing 102218, China
Abstract Background: High intraocular pressure (IOP) and low central corneal thickness (CCT) are important validated risk factors for glaucoma, and some studies also have suggested that eyes with more deformable corneas may be in higher risk of the development and worsening of glaucoma. In the present study, we aimed to evaluate the association between corneal biomechanical parameters and asymmetric visual field (VF) damage using a Corvis‑ST device in patients with untreated normal tension glaucoma (NTG). Methods: In this observational, cross‑sectional study, 44 newly diagnosed NTG patients were enrolled. Of these, 31 had asymmetric VF damage, which was defined as a 5‑point difference between the eyes according to the Advanced Glaucoma Intervention Study scoring system. Corneal biomechanical parameters were obtained using a Corvis‑ST device, such as time from start until the first and second applanation is reached (time A1 and time A2, respectively), cord length of the first and second applanation (length A1 and length A2, respectively), corneal speed during the first and second applanation (velocity A1 and velocity A2, respectively), time from start until highest concavity is reached (time HC), maximum amplitude at the apex of highest concavity (def ampl HC), distance between the two peaks at highest concavity (peak dist HC), and central concave curvature at its highest concavity (radius HC). Results: Time A1 (7.19 ± 0.28 vs. 7.37 ± 0.41 ms, P = 0.010), length A1 (1.73 [1.70–1.76] vs. 1.78 [1.76–1.79] mm, P = 0.007), length A2 (1.58 [1.46–1.70] vs. 1.84 [1.76–1.92] mm, P
Corneal Biomechanical Parameters and Asymmetric Visual Field Damage in Patients with Untreated Normal Tension Glaucoma Bai‑Bing Li1, Yu Cai1, Ying‑Zi Pan1, Mei Li1, Rong‑Hua Qiao2, Yuan Fang1, Tian Tian1 1
Department of Ophthalmology, Peking University First Hospital, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing 100034, China 2 Department of Ophthalmology, Beijing Tsinghua Changgung Hospital, Beijing 102218, China
Abstract Background: High intraocular pressure (IOP) and low central corneal thickness (CCT) are important validated risk factors for glaucoma, and some studies also have suggested that eyes with more deformable corneas may be in higher risk of the development and worsening of glaucoma. In the present study, we aimed to evaluate the association between corneal biomechanical parameters and asymmetric visual field (VF) damage using a Corvis‑ST device in patients with untreated normal tension glaucoma (NTG). Methods: In this observational, cross‑sectional study, 44 newly diagnosed NTG patients were enrolled. Of these, 31 had asymmetric VF damage, which was defined as a 5‑point difference between the eyes according to the Advanced Glaucoma Intervention Study scoring system. Corneal biomechanical parameters were obtained using a Corvis‑ST device, such as time from start until the first and second applanation is reached (time A1 and time A2, respectively), cord length of the first and second applanation (length A1 and length A2, respectively), corneal speed during the first and second applanation (velocity A1 and velocity A2, respectively), time from start until highest concavity is reached (time HC), maximum amplitude at the apex of highest concavity (def ampl HC), distance between the two peaks at highest concavity (peak dist HC), and central concave curvature at its highest concavity (radius HC). Results: Time A1 (7.19 ± 0.28 vs. 7.37 ± 0.41 ms, P = 0.010), length A1 (1.73 [1.70–1.76] vs. 1.78 [1.76–1.79] mm, P = 0.007), length A2 (1.58 [1.46–1.70] vs. 1.84 [1.76–1.92] mm, P
