Performance of huvitz HNT7000 non contact tonometer in measuring intraocular pressure

The aim of this study was to assess the performance of the Huvitz HNT7000 Non-contact Tonometer (NCT) in obtaining intraocular pressure (IOP) measurements for an objective clinical assessment of the normal intraocular pressure. The right eyes of 30 healthy subjects aged between 20–25 (23±1.46) years, with normal intraocular pressure (IOP) were assessed with both Huvitz HNT7000 Non-contact Tonometer (NCT) and Goldmann Applanation Tonometer (GAT). Three measurements were obtained with each tonometer respectively, and the averaged intraocular pressure (IOP) readings were recorded for the study. Bland-Altman analysis showed that the mean difference of measurements by two tonometers was 1.80mmHg with an agreement of 77.8%. The Shapiro-Wilk statistics indicated that the assumption of normality in Huvitz HNT7000 NCT was not violated; F_max was 1.322, demonstrating homogeneity of variances; but there is a violation in the assumption of spherecity (p = 0.038). However, based on Greenhouse-Geisser's correction in One-Way Repeated Measures ANOVA, there is no significant difference indicated in the three measurements taken by Huvitz HNT7000 NCT (p = 0.222). Therefore, there is a good repeatability of Huvitz HNT7000 NCT in obtaining intraocular pressure measurement. In conclusion, the Huvitz HNT7000 NCT demonstrates a good performance for the objective clinical assessment of intraocular pressure (IOP).