scholarly journals Repeatability of corneal biomechanics waveform signal parameters derived from Ocular Response Analyzer in children

Author(s):  
Kin Wan ◽  
Sin Wan Cheung ◽  
James Stuart Wolffsohn ◽  
Pauline Cho
2019 ◽  
Author(s):  
Dan Fu ◽  
Meiyan Li ◽  
Michael C. Knorz ◽  
Shengsheng Wei ◽  
Jianmin Shang ◽  
...  

Abstract Background: To compare intraocular pressure (IOP) measurements by a dynamic Scheimpflug analyzer (Corvis ST), a non-contact tonometer, and the ocular response analyzer following hyperopic small-incision lenticule extraction (SMILE).Methods: Thirteen patients underwent hyperopic SMILE in one eye each were prospectively enrolled. IOP and corneal biomechanical parameters were measured preoperatively and 1 week, 1 month, and 3 months after surgery with a non-contact tonometer (IOPNCT), Corvis ST (biomechanical corrected IOP, bIOP), and the ocular response analyzer (Goldmann-correlated intraocular pressure [IOPg], cornea compensated IOP [IOPcc]). A linear mixed model was used to compare IOP and biomechanical values among the methods at each time point.Results: IOPNCT, IOPg, and IOPcc dropped significantly after surgery, with the amplitude being 3.15±0.48 mmHg, 5.49±0.94 mmHg, and 4.34±0.97 mmHg, respectively, at the last visit. IOPNCT decreased by 0.11±0.06 mmHg per µm of removed central corneal thickness. bIOP did not change significantly after surgery. Before surgery, no difference was found among the measurements (P> 0.05). After surgery, IOPNCT and bIOP were higher than IOPg and IOPcc. bIOP is independent of cornea thickness at the last visit, while correlated significantly with corneal biomechanics as other three IOP values did.Conclusion: bIOP (biomechanical corrected IOP as measured with the Corvis ST) seems to be an accurate parameter to measure IOP after hyperopic SMILE.


2019 ◽  
Vol 32 (3) ◽  
pp. 1149
Author(s):  
OmniaA Attia ◽  
HassanG Farahat ◽  
KhalidE. S. Ahmed

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Kunliang Qiu ◽  
Xuehui Lu ◽  
Riping Zhang ◽  
Geng Wang ◽  
Mingzhi Zhang

Purpose. To determine the corneal biomechanical properties by using the Ocular Response Analyzer™and to investigate potential factors associated with the corneal biomechanics in healthy myopic subjects.Methods. 135 eyes from 135 healthy myopic subjects were included in this cross-sectional observational study. Cornea hysteresis (CH), corneal resistance factor (CRF), cornea-compensated intraocular pressure (IOPcc), and Goldmann-correlated intraocular pressure (IOPg) were determined with the Reichert Ocular Response Analyzer (ORA). Univariate and multivariate regression analyses were performed to investigate factors associated with corneal biomechanics.Results. The mean CH and CRF were9.82±1.34 mmHg and9.64±1.57 mmHg, respectively. In univariate regression analysis, CH was significantly correlated with axial length, refraction, central corneal thickness (CCT), and IOPg (r=-0.27, 0.23, 0.45, and 0.21, resp.; all withp≤0.015), but not with corneal curvature or age; CRF was significantly correlated with CCT and IOPg (r=0.52and 0.70, resp.; all withp<0.001), but not with axial length/refraction, corneal curvature, or age. In multivariate regression analysis, axial length, IOPcc, and CCT were found to be independently associated with CH, while CCT and IOPg were associated with CRF.Conclusions. Both CH and CRF were positively correlated with CCT. Lower CH but not CRF was associated with increasing degree of myopia. Evaluation of corneal biomechanical properties should take CCT and myopic status into consideration.


2017 ◽  
Vol 38 (2) ◽  
pp. 451-457 ◽  
Author(s):  
Betul Seher Uysal ◽  
Necati Duru ◽  
Umut Ozen ◽  
Mucella Arikan Yorgun ◽  
Emine Akcay ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document