Another great publication just out in the July issue of the American Journal of Opthalmology continues the focus on patients in the workplace having to deal with dry eye disease (DED). A few weeks ago we showed workers using video display terminals (VDT) for long periods can significantly reduce Mucin 5AC leading to physiologic damage to the ocular surface. This latest pub by Fenga et al, titled “Comparison of Ocular Surface Disease Index and Tear Osmolarity as Markers of Ocular Surface Dysfunction in Video Terminal Display Workers” compared the Ocular Surface Disease Index (OSDI) questionnaire and tear osmolarity using the TearLab Osmolarity System to evaluate ocular surface alterations in VDT users. They included 64 workers and also evaluated tear film break-up time (TBUT), fluorescein corneal stain and assessed for meibomian gland dysfunction (MGD).
The study design required subjects to have at least 2 altered signs of these three signs to be classified as having ocular surface dysfunction (OSD) or not. TearLab is a point of care CLIA Waived lab device which requires only a 50 nanoliter sample of tear that provides the clinician tear osmolarity results for both eyes in less than one minute. The ROC curve (AUC) for osmolarity (from 0.71 to 0.86) showed, for all the classification variables considered, statistically significantly higher values than those obtained with OSDI (from .51 to .58). Tear osmolarity also showed correlation with staining and ocular surface dysfunction and inversely with TBUT. The found no correlation between OSDI and the parameters considered. The study conclusion is “tear osmolarity (TO) can be considered a more reliable test then OSDI when screening VDT users for possible ocular surface alterations”.
Read more here.
Authors: C. Fenga et al.