ABSTRACT
AIM:To compare the non-invasive tear break-up time (NITBUT) and tear meniscus height (TMH) measurements in keratoconus patients and normal subjects, and to determine the relationship between these measurements with keratoconus disease by the Oculus Keratograph 5M (K5M).METHODS:Fifty keratoconus patients (100 eyes) and 50 healthy subjects (100 eyes) participated in the study.The age range in keratoconus group was 15-60(mean ± standard deviation=28.33±8.60) y, and in control group was 18-60(26.25±1.11) y.The measurements of NITBUT and TMH were performed using the K5M.RESULTS:The mean value of NITBUT between the keratoconus group and the control group showed no statistically significant different (P=0.58).Also, the mean of TMH between two groups was not significantly different (P=0.69).The results of correlation coefficient between the variables of the study demonstrated that there was no significant relationship between the NITBUT and TMH measurements with the two groups (keratoconus group:r=0.053, P=0.721;control group;r=-0.0501, P=0.7098).CONCLUSION:Our study shows that the presence of keratoconus has no clinically significant impact on the quality and quantity of tear film.