OT skills guide: non-invasive tear break-up time

[@morningofheaven446]

Great knowledge

[@elamyslimi5496]

Thanks a lot for showing....

[@zaidalhabshi]

I have dry eyes and my TBUT is 3 to 4 seconds.however,using keratoscope, NITBUT is 18 to 20 seconds. why there is a big difference in the results?

[@ВоронМаусы]

most likely due to the disruption of the tear film by the fluorescein during the invasive TBUT