scholarly journals Comparison of the Icare ic100 rebound tonometer and the Goldmann applanation tonometer in 1000 eyes

2020 ◽  
Author(s):  
Arjun Gopal Subramaniam ◽  
Penelope Allen ◽  
Tze'Yo Toh
2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Mahmoud Rateb ◽  
Mahmoud Abdel-Radi ◽  
Zeiad Eldaly ◽  
Mohamed Nagy Elmohamady ◽  
Asaad Noor El Din

Purpose. To evaluate the different IOP readings by Goldmann applanation tonometer (GAT), ICare rebound tonometer, and Tono-Pen in keratoconus patients after MyoRing implantation. To assess the influence of central corneal thickness (CCT) and thinnest corneal location (TCL) on IOP measurements by different tonometers. Setting. Prospective observational study was conducted in two private centers in Egypt from February 2015 to November 2016. Methods. Seventeen eyes of 10 patients suffering from keratoconus and who underwent MyoRing implantation were recruited. All subjects underwent GAT, ICare, and Tono-Pen IOP measurements in random order. Central corneal thickness and thinnest corneal location were assessed by Pentacam. Difference in mean in IOP readings was assessed by T-test. Correlation between each pair of devices was evaluated by Pearson correlation coefficient. The Bland–Altman analysis was used to assess intertonometer agreement. Results. Seventeen eyes (10 patients) were evaluated. The mean IOP reading was 13.9 ± 3.68, 12.41 ± 2.87, and 14.29 ± 1.31 mmHg in GAT, ICare, and Tono-Pen group, respectively. There was a significant difference between IOP readings by GAT/ICare and Tono-Pen/ICare (p value: 0.032 and 0.002, respectively) with no significant difference between GAT/Tono-Pen (p value: 0.554). Mean difference in IOP measurements between GAT/ICare was 1.49 ± 2.61 mmHg, Tono-Pen/ICare was 1.89 ± 2.15 mmHg, and GAT/Tono-Pen was −0.39 ± 2.59 mmHg. There was no significant correlation between the difference in IOP readings among any pair of devices and CCC or TCL. The Bland–Altman analysis showed a reasonable agreement between any pair of tonometers.


2019 ◽  
Vol 28 (2) ◽  
pp. 172-177 ◽  
Author(s):  
Shunsuke Nakakura ◽  
Etsuko Mori ◽  
Yuki Fujio ◽  
Yasuko Fujisawa ◽  
Kanae Matsuya ◽  
...  

2020 ◽  
pp. 112067212092138
Author(s):  
Katri Stoor ◽  
Elina Karvonen ◽  
Pasi Ohtonen ◽  
M Johanna Liinamaa ◽  
Ville Saarela

Purpose The aim of this study was to compare the measurements of intraocular pressure by two tonometers, the Icare rebound tonometer and the Goldmann applanation tonometer, in a randomised screening study. The influence of refraction and central corneal thickness on the measurements was also evaluated. Methods Intraocular pressure was measured with rebound tonometer and Goldmann applanation tonometer in 1266 participants; refraction and central corneal thickness were also determined. One randomised eye of each participant was selected for this report’s analysis. A Bland–Altman plot was used to compare the values obtained with the two devices. Results The correlation between rebound tonometer and Goldmann applanation tonometer was good: the intraclass correlation coefficient (r) between the two methods was 0.735 ( p < 0.001). The mean difference (rebound tonometer–Goldmann applanation tonometer) was 0.11 ± 2.3 mmHg. The difference was not statistically significant (95% confidence interval: 0.11 to 0.13, p = 0.09). With increasing central corneal thickness, not only did intraocular pressure values with both devices increase, but the difference between them also increased. Refraction (spherical equivalent) did not influence intraocular pressure or the rebound tonometer–Goldmann applanation tonometer difference. However, high astigmatism (≥2D) exerted an influence on intraocular pressure values taken with Goldmann applanation tonometer. Conclusion Measurements with rebound tonometer and Goldmann applanation tonometer are relatively uniform although rebound tonometer slightly overestimated intraocular pressure. Both rebound tonometer and Goldmann applanation tonometer and the difference between these devices were affected by central corneal thickness but not by refraction. Higher astigmatism affected Goldmann applanation tonometer more than rebound tonometer. It is concluded that rebound tonometer is a reliable method for measuring intraocular pressure in a population-based screening study.


Author(s):  
Santanu Das ◽  
Nayana Nagesh ◽  
Kiran Kumar L ◽  
Sundeep Shetty

ABSTRACT: AIM-To compare the intraocular pressure (IOP) measured by Non-Contact tonometer (NCT), Rebound tonometer (RBT) and Goldmann Applanation tonometer (GAT) and their correlation with central corneal thickness (CCT), true IOP and corneal curvature. Reliability of each tonometer. METHODS-500 random patients aged 18 years and above were taken up for the study. Patients with anterior and posterior segment pathologies like corneal ulcer, leukoma, staphyloma, corneal lacerations, ectatic corneal conditions, corneal dystrophies, oedema, perforations, acute angle closure glaucoma, retinal detachments, vitreous haemorrhage and unwilling patients were excluded from the study. IOP was recorded using NCT, RBT and GAT after assessing the patient's visual acuity. Following IOP measurement, central corneal thickness (CCT) of each patient was measured using pachymetry. Kvalues were measured using an autorefractometer. All the data were collected and tabulated for statistical analysis to obtain results. RESULTS: The mean CCT in males was 0.5350 mm and in females 0.5340 mm respectively. The mean IOP measured by NCT is 16.43 mm hg whereas the mean IOP measured by GAT is 15.43 mm hg. IOP measured by NCT is significantly higher than the IOP measured by GAT (p<0.001). When NCT and RBT are compared NCT values are significantly higher than that of RBT(p<0.001). Although the mean RBT IOP 15.83 mm hg is higher than the mean GAT IOP of 15.42 mm hg the values are not statistically significant. When correlated with CCT all the tonometers showed significant correlation with GAT showing the strongest correlation. NCT overestimates IOP in normal, thin and thicker corneas when compared to GAT and are statistically significant. RBT also overestimates in the normal and thick corneas when compared to GAT but their values are much closer to GAT values in thinner corneas. The IOP measured by all the 3 tonometers correlated with corrected IOP with NCT showing the best correlation followed by GAT. There was no significant correlation between K and IOP in our study. CONCLUSION-From the present study we can conclude that IOP measured by NCT and RBT is higher than GAT. NCT values are significantly higher than GAT values in thin and normal corneas whereas it overestimates more in thicker corneas. RBT values are significantly higher than that of GAT in normal and thick corneas. All the tonometers show significant correlation with CCT with GAT showing the strongest correlation. So, it is always advisable to measure the corrected IOP for each patient after considering the CCT. Keywords- Non-contact tonometer; Goldmann applanation tonometer; central corneal thickness; intraocular pressure; Rebound tonometer, true IOP, Corneal curvature.  


2011 ◽  
Vol 70 (3) ◽  
Author(s):  
N. Rampersad ◽  
K. P. Mashige ◽  
S. Jhetam

The purpose of this study was to compare the intraocular pressure (IOP) values measured with the Tono-Pachymeter NT530P (Tonopachy™) and the iCare® rebound tonometer (iCare®) with those obtained by the Goldmann applanation tonometer (GAT). The right eyes of 105 subjects aged 18 to 82 years (mean age = 29.27 ± 14.67 years) were assessed with the three tonometers. Central corneal thickness (CCT) was measured first using the Tonopachy™ and then IOP was measured by Tonopachy™, iCare® and GAT. The data was analyzed with descriptive statistics, paired  t-test, correlation and regression analysis. The Bland-Altman method of analysis was used to evaluate agreements between the sets of data from the three devices. The CCT values ranged from 440 µm to 606 µm (mean= 518.49 ± 33.01 µm). There was little or no correlation between CCT and IOP for any of the instruments used in this study (r = 0.29 for Tonopachy™, r = 0.22 for iCare®, r = 0.17 for GAT). The mean IOP measured with the Tonopachy™ was 14.31 ± 3.57 mmHg (range 8.7 mmHg to 31 mmHg) and 16.64 ± 4.38 mmHg (range 8 mmHg to 32 mmHg) using the iCare®. The mean IOP measured with the GAT was 14.79 ± 3.09 mmHg (range 8.7 mmHg to 29.7 mmHg). Using the Bland-Altman method, the upper and lower limits of agreement between the Tonopachy™ and GAT, iCare® and GAT, iCare® and Tonopachy™ were 5.1 mmHg and –4.2 mmHg, 8.6 mmHg and –4.9 mmHg, 7.5 mmHg and –2.8 mmHg respectively. In 79.1% of the eyes studied, the mean IOP difference between Tonopachy™ and GAT was less than 3 mmHg and in 20.9% of the eyes, the difference was greater than 3 mmHg. However, mean IOP differences of greater than 3 mmHg were obtained by iCare® in comparison with GAT (40%) and Tonopachy™ (34.3%) respectively. Findings of this study suggest that the Tonopachy™ yielded IOP readings that were consistent with those of GAT values while iCare® yielded higher IOP values compared to both GAT and Tonopachy™. (S Afr Optom 2011 70(3) 109-116)


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