High-Resolution Ocular Surface Imaging: Real-Time Visualization of Tear Film Dysfunction

Recent advancements in infrared sensing technology have made it possible to visualize tear film dynamics in real time, enabling evaluation of tear film quality during blinking. A retrospective clinical evaluation was conducted to explore this by grading videos of the tear film and comparing grading data with dry eye diagnostic results using the OCULUS keratograph (K5M).

Videos were used to grade patients' tear film perturbations as compared with healthy control subjects. The grading was then correlated with the ocular surface disease index (OSDI) scores, tear film breakup time (TFBUT), tear meniscus height (TMH), corneal staining, redness, and meibography data.

Infrared imaging of the ocular surface revealed instantaneous and recurring dynamic characteristics of the tear film, allowing for the differentiation between normal and abnormal tear films. Abnormal features included a complete absence of a spreading tear film, hindered spreading of the tear film after blinking, areas of tear film instability, or a combination of the latter 2. Some of these features show a resemblance to the tear film appearance after fluorescein staining. The grading of these features correlated with TFBUT and, to a lesser extent, with TMH but did not show significant correlation with any other diagnostic data from the K5M. Furthermore, the speed of tear film spreading after blinking showed a positive correlation with TMH.

Direct visualization of the tear film across the entire palpebral aperture using infrared sensing offers a noninvasive, reproducible, and rapid method for assessing the health and quality of the tear film.