Comparison of proview phosphene tonometer with the goldmann applanation tonometer in myopic and non-myopic eyes

Aim: To compare intraocular pressure measurements using the Proview phosphene tonometer and Goldman applanation tonometer in myopic eyes and non-myopic eyes. Methods: Seventy two patients (132 eyes) were enrolled in the study. On the basis of refraction, the patient's eyes were classified into group 1 (non-myopic eyes) and group 2 (myopic eyes). All patients underwent Goldman applanation tonometry and self-measurement of intraocular pressure using the Proview phosphene tonometer. Linear regression analysis was performed to evaluate age, refraction, and intraocular pressure measured using the 2 tonometers. Pearson correlation was used to assess the correlation of intraocular pressure, paired samples t test was used to investigate for differences, and agreement was assessed using the Bland-Altman plots and intraclass correlation coefficient. Results: There was a moderate level of agreement between the Goldman applanation tonometer and the Proview phosphene tonometer (intraclass correlation coefficient = 0.824). The 95% confidence intervals of agreement of intraocular pressure measured by the Proview phosphene tonometer and the Goldman applanation tonometer were narrower for the myopic eyes (-4.07 to + 4.36 mm Hg) than for the non-myopic eyes (-5.90 to +4.98 mm Hg). The difference in intraocular pressure between the Goldman applanation tonometer and the Proview phosphene tonometer was not significantly associated with refraction or age. The difference in intraocular pressure measured by the 2 tonometers was not significant. Conclusions: There is moderate agreement between the Proview phosphene tonometer and the Goldman applanation tonometer. The myopic eyes showed slightly better agreement than non-myopic eyes but the difference was not statistically significant.