Validation of a New Software Application for Tear Breakup Measurement

Abstract

[Abstract]: Significance: Tear film instability has been recognized as one key mechanism on dry eye disease. There is a need for new instruments, methods, or protocols to improve the repeatability and reproducibility of the tear film stability to facilitate its clinical evaluation use as a rapid and reliable primary diagnostic test. Purpose: The present pilot study aimed to validate a method to automatically measure the tear film breakup time (BUT). Methods: A total of 264 videos of BUT were randomly selected among the clinical history of subjects attending the optometry clinic. Videos were stored in a backup server through a secure file transfer protocol and analyzed by three different examiners: two masked observers (subjective evaluation) and a third investigator using the automatic software application (objective evaluation). Subjective evaluation was conducted only once on an online software designed for this protocol where videos were presented in random masked order. Automatic evaluation based on color and texture analysis was performed by (1) automatic localization of sequences of interest in the video, (2) extraction of the region of interest within each frame, and (3) automatic BUT measurement from evolution curves in the region of interest as time elapsed from the beginning of the sequence of interest until the curve exceeds a threshold. Results: Substantial correlation was observed among the examiners (intraclass correlation coefficient, 0.752). There was a statistical difference between observer 1 and 2 evaluations (t test, P < .001), whereas data provided by the software showed no significant differences from those of the observers (t test, P ≥ .26). Similar results to the whole data set analysis were obtained when the sample was reassessed only considering mean BUT values ≤15 seconds. Conclusions: The present pilot study showed acceptable clinical results for the software application designed to objectively measure the BUT.