Diagnosing DED is challenging, mainly because of the discordance between signs and symptoms: patients can have severe symptoms, yet show no sign of ocular surface damage; others have advanced damage to the ocular surface, yet report no symptoms, as their ocular surface is so damaged, they can no longer feel anything.
Figure 1. Application of fluorescein to a patient’s cornea.
Historically, there has been a lack of correlation between patients’ irritative ocular symptoms (e.g., as determined by questionnaires) and the results of commonly performed tests such as corneal fluorescein staining (CFS, Figure 1) or the tear film break up time (TFBUT). We will explore why, and learn how this is changing for the better.
