Repeatability of non-invasive break-up time measures with a new automated dry eye platform in healthy eyes

Abstract

Purpose To evaluate the intrasession repeatability for non-invasive break-up time (NIBUT) and tear meniscus height (TMH) measurements provided by a new multi-diagnostic platform, and to assess the interobserver reproducibility of TMH measures. Methods Twenty-one healthy eyes of 21 patients (age, 23–65 years) were enrolled. A complete eye examination was performed in all cases with the VX120+ device (Visionix-Luneau Technologies), including an analysis with the new Dry Eye module, performing three consecutive measurements. The within-subject standard deviation (Sw) and Bland–Altman plots were used to assess intersession repeatability. Differences between examiners for TMH were also analysed. Results No statistically significant differences were found between repeated measures of NIBUT (time associated with the first break) and TMH (p > 0.05). However, significant differences were found for NIBUT50% (time associated with half of breaks of the tear film) (p < 0.05). Mean Sw was 0.9 s, 1.4 s and 0.05 mm for NIBUT, NIBUT50% and TMH, respectively. Ranges of agreement between consecutive measures were below 3.5 s and 4.5 s for NIBUT and NIBUT50%, respectively, and below 0.16 mm for TMH. Furthermore, no significant differences were found between examiners in TMH measure, with an inter-examiner range of agreement of 0.12 mm. Conclusions The new dry eye platform of the VX120+ platform evaluated provides objective automated measures of NIBUT and TMH, with acceptable level of intrasession repeatability for clinical screening purposes.