Noninvasive Imaging of Tear Film Dynamics in Eyes With Ocular Surface Disease

Purpose: To test the validity of ocular surface assessment tools offered by a corneal topographer (Oculus Keratograph 5M). Methods: Over 9 months, 296 eyes were imaged and divided into 2 groups: ocular surface disease (OSD) group (223 eyes) with clinically diagnosed meibomian gland dysfunction or dry eye syndrome and control group (73 eyes). All eyes were imaged using the noninvasive Keratograph tear breakup time (NIKBUT), tear meniscus height (TMH), and meibography tools of the Oculus K5M. Traditional methods using fluorescein staining were used to measure tear breakup and meniscus height. Meibography images were graded using the hand tracing method and a novel blue boundary method. Results: Oculus TMH values were statistically significantly higher in the OSD group than the control group (0.4:0.3 mm, P<0.001), whereas traditional fluorescein values were higher in the control group (0.4:0.2 mm, P<0.01). Oculus NIKBUT values were not statistically significantly different between the OSD and control groups (6.7:8.2 seconds, P = 0.69), whereas fluorescein breakup time values were statistically significantly higher in the control group (6.7:5.6 seconds, p<0.05). The meibography hand tracing method showed higher sensitivity between the control group and glandular atrophy (17%:28%, p<0.05), whereas the blue boundary method showed higher reproducibility (6.9%:23.8%, p<0.001). Conclusions: The Oculus K5M can provide automated measurements of tear film dynamics and meibography images without using fluorescein or cobalt blue light. However, the automated TMH and NIKBUT were not in agreement with traditional measurements using fluorescein staining. Meibography highlights glandular architecture, which can be used to analyze glandular density and glandular atrophy.