Abstract
Purpose:
To assess the ability of two different treatments techniques to manage tear film disruption that results from exposure to a low relative humidity (RH).
Methods:
Two environmental conditions (40%RH/210C and 5%RH /210C) were created using a controlled environmental chamber. At 5% RH,Rohto Dry Eye Relief drop was instilled in two different modalities, Protection and Relief. At protection visit, Rohto drop was instilled before the exposure, while in relief technique, subjects were exposed to low RH for 15 minutes, and then the Rohto drop was instilled. Rohto was selected for its novel formulation as it contains a biopolymer of hyaluronic acid and tamarind seed polysaccharide. Evaporation rate, lipid layer thickness (LLT), noninvasive tear breaks up time (NITBUT), osmolarity and ocular comfort were assessed in normal and dry environmental conditions with the use of Rohto in two different treatment modalities.
Results:
All tear film parameters (except Osmolarity, p=0.055) were adversely affected by the exposure to low RH (p<0.05). The use of Rohto drops in both techniques resulted in improvement in LLT, NITBUT and ocular comfort during exposure to 5%RH (p<0.05).Tear evaporation was significantly improved in protection technique (p=0.008) but not in the relief method (p=0.09) in compare to 5%.
Conclusions:
Protection and relief techniques were shown to be effective. Using Rohto eye drops before exposure to dry environment (Protection) was superior to relief for tear evaporation. Therefore, for maximum effect, it is recommended to use Rohto prior to exposure to desiccating environment such as this found in aircraft. The present study demonstrates that using CEC has the potential to provide researchers with a readily available method to evaluate rapidly the efficiency of tear supplementation. By using the CEC, tear film parameters that are typical to those with dry eye patients could be simulated easily in the laboratory environment. This new method allows further evaluation of tear film parameters and dry eye treatment protocols in labs before try it on dry eye patients.