Biomechanically-corrected intraocular pressure compared to pressure measured with commonly used tonometers in normal subjects

Sedaghat, M. R. and Momeni-Moghaddam, H. and Yekta, A. and Elsheikh, A. and Khabazkhoob, M. and Ambrósio, Jr. and Maddah, N. and Danesh, Z. (2019) Biomechanically-corrected intraocular pressure compared to pressure measured with commonly used tonometers in normal subjects. Clinical Optometry, 11. pp. 127-133.

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Purpose: To compare the biomechanically-corrected intraocular pressure (bIOP) measured by the Corvis ST (Oculus, Wetzlar, Germany) with IOP measurements made by other commonly used tonometers; and to test the correlations between IOP measures and central corneal thickness. Methods: One randomly-selected eye from each of 94 healthy subjects was assessed. The bIOP was determined by the CorVis ST and compared with the IOP measurements made by standard Goldmann Applanation Tonometer (GAT: Haag-Streit AG, Bern, Switzerland), the Icare (Icare Finland Oy, Vantaa, Finland), and the Ocular Response Analyzer (ORA-IOPcc: Reichert, New York, USA). Corneal thickness was assessed by the Oculus Pentacam. The correlation between bIOP and the other devices and between CCT were assessed using the Pearson correlation test or Spearman’s rho test accordingly to the distribution of these values. The Bland-Altman method and intraclass correlation coefficients (ICC) were used to assess the agreement of bIOP results with IOP obtained with other techniques. The limits of agreement (LoA) were determined as the mean difference ±1.96 SD of the mean differences. In all tests, the significance level was considered to be 0.05. Results: Mean and SD of the bIOP were 16.11±1.66 mmHg. Significant differences were found between the bIOP and other IOP measurements (GAT, 3.02±2.60 mmHg, p<0.001, Icare, 1.51±2.95 mmHg, p<0.001, IOPcc, 1.09±1.96 mmHg, p<0.001). The lowest and highest mean differences in IOP were with the IOPcc and GAT, respectively. Interestingly, there were no significant differences in bIOP, GAT-IOP and ORA-IOPcc between the eyes with thin or thick corneal thicknesses, with Icare-IOP being the only exception (p<0.001). Conclusion: The Corvis bIOP has a higher correlation with the IOPcc by ORA, which are also compensated for the effects of corneal biomechanics and have less association with corneal thickness relative to the uncorrected GAT and Icare measurements. © 2019 Sedaghat et al.

Item Type: Article
Additional Information: Export Date: 16 February 2020 Correspondence Address: Momeni-Moghaddam, H.; Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Parastar 2 Str., Ahmadabad Blvd., Iran; email:
Uncontrolled Keywords: Corneal biomechanics Intraocular pressure Tonometry
Subjects: W General medicine- Health professions
Divisions: Mashhad University of Medical Sciences
Depositing User: mr lib1 lib1
Date Deposited: 27 Jun 2020 05:38
Last Modified: 27 Jun 2020 05:38

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