Abstract
Tear meniscus height (TMH) is an indirect measurement of tear film volume. This study investigated the temporal changes in the TMH during the blink interval in the morning (8-9 am) and at the end of the day (5-6 pm) in both soft contact lens (CL) and nonlens wearers (NLW). Fifty participants (25 CL; 25 NLW) were evaluated for their subjective symptoms, TMH, noninvasive break up time, and bulbar hyperemia at the am and pm visits on the same day. The TMH was measured at set intervals between 2 and 15 sec during the blink interval, using an optical coherence tomographer. The NLW group revealed no changes in a variety of symptoms during the day, whereas the CL group reported an increase in dryness (P=0.03) and grittiness (P=0.02) over the day. For both groups, the TMH and calculated tear meniscus volume revealed lower values immediately after the blink and increased progressively afterwards, mainly due to reflex tearing. The am tear meniscus volume values tended to be higher than the pm values for both groups, but this was not significant (NLW P=0.13; CL P=0.82). Noninvasive break up time deteriorated during the day for both groups but was only significant for the CL group (P=0.002), whereas bulbar hyperemia revealed no statistically significant change for either group. Reflex tearing may play a substantial role in the TMH differences observed over the blink interval. Standardization of the time when a TMH measurement is performed will be valuable in comparing tear film clinical studies.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Eye & Contact Lens: Science & Clinical Practice
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
