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

Silva, N; Ferreira, André; Baptista, Pedro Manuel; Figueiredo, Américo; Reis, Rita; Sampaio, Isabel; Beirão, João Melo; Vinciguerra, Riccardo; Menéres, Pedro; MJ, Menéres

doi:10.2147/opth.s350029

Cited by 14 publications

(15 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some reported corneas of POAG were less deformable compared to controls, 17 , 29 whereas others reported that no biomechanical differences were found between the two groups. 30 , 31 The possible reasons for this disagreement could be due to the influences of antiglaucoma medications on corneal biomechanics, differences in sample size and variables used for adjustment. When NTG and HTG were analyzed separately and compared with controls ( Table 2 ), DA, AT1 and HC time showed similar changes in the two glaucoma groups.…”

Section: Discussionmentioning

confidence: 99%

Association Between Ocular Biomechanics Measured With Corvis ST and Glaucoma Severity in Patients With Untreated Primary Open Angle Glaucoma

Chen

Sun

2022

Trans. Vis. Sci. Tech.

View full text Add to dashboard Cite

Purpose To compare the ocular biomechanical differences between normal controls and patients with untreated primary open angle glaucoma, including normal-tension glaucoma (NTG) and high-tension glaucoma (HTG), and to investigate the association between ocular biomechanics and glaucoma severity in each group. Methods One hundred fifty-three eyes of 153 subjects, including 51 controls, 47 NTG, and 55 HTG cases, were enrolled in this cross-sectional study. Each participant underwent biomechanical measurements by using the Corneal Visualization Scheimpflug Technology. Glaucoma severity was evaluated by mean deviation (MD), pattern standard deviation (PSD), ganglion cell complex (GCC), and retinal nerve fiber layer (RNFL) thickness. Results Deformation amplitude ( P = 0.001) significantly increased, whereas first applanation time ( P < 0.0001), highest concavity time ( P = 0.001), stiffness parameter at first applanation ( P = 0.009), and time of whole eye movement (WEM, P = 0.008) decreased significantly in NTG eyes compared with controls. Besides, NTG had the highest first applanation velocity than controls ( P < 0.0001) and HTG ( P = 0.044). Shorter time of WEM was independently correlated with worse MD ( P = 0.02) and higher values of PSD ( P = 0.03) in NTG. Axial length was positively related to PSD ( P = 0.02) and negatively related to GCC ( P < 0.0001) and RNFL ( P < 0.0001) thickness in HTG. Conclusions NTG corneas are more deformable than healthy ones and HTG. Time of WEM, which relates to orbital compliance, is significantly associated with glaucomatous visual field defect in NTG, whereas axial length is correlated with glaucoma severity in HTG. Translational Relevance Ocular biomechanics may partly account for the differences of pathogenic mechanisms between NTG and HTG.

show abstract

Section: Discussionmentioning

confidence: 99%

Association Between Ocular Biomechanics Measured With Corvis ST and Glaucoma Severity in Patients With Untreated Primary Open Angle Glaucoma

Chen

Sun

2022

Trans. Vis. Sci. Tech.

View full text Add to dashboard Cite

show abstract

“…Eighteen of the 31 articles used ORA to investigate differences in corneal biomechanical parameters between glaucoma patients and normal controls, 10,14,[24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] while 15 used CST. 11,16,36,37,[40][41][42][43][44][45][46][47][48][49][50] The procedure of the literature search and the reasons for exclusion are shown in Fig. 1.…”

Section: Characteristics Of the Studies Included In The Meta-analysismentioning

confidence: 99%

“…[11][12][13] Otherwise, several studies have suggested that patients with ocular hypertension (OHT) but no glaucomatous changes showed less deformable corneas. 9,10,[14][15][16] These corneal biomechanical differences indicate that the appearance and progression of glaucoma could be associated with specific corneal biomechanical DOI: 10.1097/IJG.0000000000002170 changes, 17,18 which may offer a novel perspective on glaucoma pathology.…”

mentioning

confidence: 99%

Corneal Biomechanics in Primary Open Angle Glaucoma and Ocular Hypertension: A Systematic Review and Meta-analysis

Liu

Zhou

et al. 2022

Journal of Glaucoma

View full text Add to dashboard Cite

Précis: Normal tension glaucoma patients had softer corneas than normal controls, whereas high-tension glaucoma and ocular hypertension patients had stiffer corneas.Purpose: To comprehensively identify the corneal biomechanical differences of patients with primary open angle glaucoma (POAG) and ocular hypertension (OHT) using the Ocular Response Analyzer or the Corvis ST. Methods:The electronic databases PubMed, Embase, and Web of Science were comprehensively searched for studies comparing corneal biomechanical differences between POAG and OHT patients with normal controls by Ocular Response Analyzer or Corvis ST. The weighted mean differences and 95% confidence intervals (CIs) were calculated. Subgroup analyses were performed according to the subtypes of POAG, including high-tension glaucoma (HTG) and normal tension glaucoma (NTG).Results: Thirty-one case-control studies were ultimately included, with 2462 POAG patients, 345 OHT patients, and 3281 normal controls. The corneal hysteresis (CH), corneal resistance factor (CRF), and highest concavity time (HC-t) were all lower in POAG patients than in normal controls. The CH, time at the second applanation (A2t), HC-t, highest concavity radius (HC-R), and deformation amplitude at the highest concavity (HC-DA) were lower in OHT patients, while the CRF, time at the first applanation (A1t), and stiffness parameter at the first applanation (SP-A1) were greater in OHT patients than in normal controls. The subgroup analyses showed that the CH, A2t, length at the second applanation (A2L), and HC-DA were lower in HTG, and the CH, CRF, A1t, and HC-t were lower in NTG patients than in normal controls. Conclusion:The corneas of NTG patients are more deformable than normal controls, whereas the corneas of HTG and OHT patients are stiffer.

show abstract

“…Thus, SSI could be suitable for the assessment of reduction in corneal stiffness in the natural progression of keratoconus and help recognize potential keratoconic eyes ( Padmanabhan et al, 2022 ; Liu et al, 2021a ). Some studies reported correlations between SSI values and IOP; therefore, SSI values may also be used for the differentiation of glaucoma types ( Ye et al, 2021 ; Silva et al, 2022 ).…”

Section: Introductionmentioning

confidence: 99%

Effect of myopia and astigmatism deepening on the corneal biomechanical parameter stress-strain index in individuals of Chinese ethnicity

Liu

Pang

Ming

et al. 2022

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

Purpose: To investigate the differences in corneal biomechanical parameter stress–strain index (SSI) among different degrees of myopic eyes in Chinese individuals and to analyze the relevant factors of the SSI.Methods: This study analyzed the right eyes of 240 participants (240 eyes) aged 18–34 years. The participants were divided into low-, moderate-, high-, and ultra-high myopia groups according to their spherical equivalent (SE), with 60 eyes included in each group. Spherical, cylinder, and SE were measured via automatically integrated optometry. Intraocular pressure (IOP) was measured using a non-contact tonometer. AL was measured using an IOLMaster device. Corneal curvature and central corneal thickness (CCT) were measured using a Pentacam. SSI and biomechanical corrected IOP (bIOP) were measured via corneal visualization Scheimpflug technology (Corvis ST). The statistical analyses included one-sample Kolmogorov–Smirnov tests and normal distribution histogram methods, Levene variance homogeneity tests, Pearson’s correlation analyses, multiple linear stepwise regression analyses, one-way ANOVA, and LSD t-tests.Results: The mean (±SD) age of the 240 participants was (24.97 ± 4.16) years. The SSI was positively correlated with spherical, cylinder, SE, CCT, IOP, and bIOP and negatively correlated with K1 and AL (r = 0.475, 0.371, 0.497, 0.169, 0.291, 0.144, −0.154, and −0.464, respectively; all p < 0.05), but were not correlated with age, K2, or Km (all p > 0.05). Multiple linear regression analysis performed with SSI as the dependent variable, and spherical, cylinder, K1, CCT, and IOP as independent variables produced the following regression equation: SSI = 0.989 + 0.017 spherical + 0.042 cylinder +0.018 IOP (R2 = 0.402, F = 31.518, p < 0.001). The SSI values in the low-, moderate-, high-, and ultra-high myopia groups were 0.945 ± 0.135, 0.940 ± 0.128, 0.874 ± 0.110, and 0.771 ± 0.104, respectively. The values decreased sequentially, and the differences between pairs were statistically significant (all p < 0.05), except for that between the low- and moderate-myopia groups (p > 0.05).Conclusion: SSI decreased with increasing myopia and astigmatism in the Chinese participants. The SSI was significantly lower in high and ultra-high myopia, especially ultra-high myopia. These findings indicate that increased corneal elasticity may be related to the pathogenesis of high and ultra-high myopia.

show abstract

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

Cited by 14 publications

References 46 publications

Association Between Ocular Biomechanics Measured With Corvis ST and Glaucoma Severity in Patients With Untreated Primary Open Angle Glaucoma

Association Between Ocular Biomechanics Measured With Corvis ST and Glaucoma Severity in Patients With Untreated Primary Open Angle Glaucoma

Corneal Biomechanics in Primary Open Angle Glaucoma and Ocular Hypertension: A Systematic Review and Meta-analysis

Effect of myopia and astigmatism deepening on the corneal biomechanical parameter stress-strain index in individuals of Chinese ethnicity

Contact Info

Product

Resources

About