Relationship of Symptomatology with Closed Chamber Infrared Thermometry and Humidity in Dry Eyes

Purpose To evaluate the relationship of symptoms of dry eye with closed chamber infrared thermometry and humidity measurements. Methods The authors studied 54 patients (108 eyes) with dry eye disorders of different grades of clinical severity (mean age 35.75±14.37 years), 31 cases (62 eyes) with normal eyes (mean age 33.68±14.42 years), and 10 cases (20 eyes) with epidemic conjunctivitis (mean age 33.68±14.42 years). The symptoms and the clinical tests (Schirmer-1 test, fluorescein tear break up time, Lissamine green stain; closed chamber infrared thermometry and humidity) were used to establish the diagnosis of dry eyes. The closed chamber humidity difference was used to classify the groups of dry eye. Results The authors noted no temperature difference from closed to open eye position in dry eyes as compared to 0.10±0.00 °C difference in normal eyes and epidemic conjunctivitis. Four groups of cases were identified by difference in values of humidity: Group 1 = <0.9 relative humidity (RH)% to 1 RH%; Group 2 = >1 RH% to 1.5 RH%; Group 3 = >1.5 RH% to 2 RH %; and Group 4 = >2 RH%. The symptomatology was measured in the eyes using Oxford scale (0–4) and correlated with the humidity groups. The grading of symptoms with the humidity showed a statistically significant relationship (p<0.0001) in each group. The severity of the symptoms showed an increase in frequency and severity from Group 1 to Group 4, which was statistically significant (p<0.0001). The mean sum total of global symptomatology score was statistically significant (p<0.0001): 3.43±0.31 in Group 1, 4.65±0.42 in Group 2, 8.56±0.78 in Group 3, and 13.35±1.21 in Group 4. However, total symptomatology score in epidemic conjunctivitis did not show a statistically significant value (p=0.20). Conclusions The closed chamber humidity and thermometry measurements showed statistical correlation in all four groups of dry eyes to total mean symptomatology score (p<0.001) and showed an increase in value with increasing severity of symptoms. However, all individual symptoms fail to show any conclusive relationship.