Correlation in a Change in Aqueou Tear Evaporation With a Change in Relative Humidity and the Impact

Purpoe To etablih cientific relationhip between relative humidity (RH) and aqueou tear evaporation to elucidate poible ignificance of thi relationhip in normal and aqueou tear deficiency patient. Deign Propective experimental laboratory tudy. Method Ocular urface evaporation wa determined uing evaporometry and calculated for two range of RH, 25% to 35%, and 35% to 45% in a randomized clinical patient population. Reult Average evaporative rate in the higher humidity range wa between 0.029 ± 0.009 through 0.043 ± 0.016 μl/cm2/min. At lower humidity, range wa between 0.044 ± 0.013 through 0.058 ± 0.018 μl/cm2/min. Difference in the correponding evaporative rate were tatitically ignificant (between P < .003 through P < .043) for each analyi. Concluion A decreae of 10% RH reulted in an average difference of between 28.33% to 59.42% increae in evaporation. The increae in evaporation at lower humidity ha ignificant clinical implication for patient with aqueou deficient dry eye, and poibly thoe undergoing laer-aited in itu keratomileui (LAIK).