The Relationship Between Tear Ferning Patterns and Non-invasive Tear Break-up Time in Normal Asian Population

PURPOSE: To investigate the relationship between tear ferning patterns (TFP) and non-invasive tear break-up time (NIBUT) in normal Asian subjects. METHODS: One hundred and forty-five adults with no ocular surface disorders were recruited. TFP and NIBUT were determined. Tears were collected using a capillary tube and allowed to air dry at room temperature for 10 min. TFP was later observed using a light microscope and classified according to Rolando's classification. Measurement for NIBUT was obtained using a Tearscope with the slit lamp magnification. RESULTS: It was found that there is no significant difference between gender in TFP (Z=−1.77, P>.05) and NIBUT (Z=−1.475, P>.05). There is also no significant difference between Malay, Chinese, Indian, and other races in TFP, (H(3)=4.85, P>.05) and NIBUT (H(3)=2.18, P>.05). However, there is a significant difference between age groups of 20–29, 30–39, 40–49,and 50–60 years old in both TFP (H(3)=28.25, P<.01) and NIBUT (H(3)=36.50, P<.001). Spearman's correlation showed there was a significant relationship between TFP and NIBUT (r=−0.55, P<.001), age and NIBUT (r=−0.50, P<.001), age and TFP (r=0.41, P<.001), McMonnies score and NIBUT (r=−0.40, P<.001), McMonnies score and TFP (r=0.31, P<.001), as well as age and McMonnies score (r=0.52, P<.001). CONCLUSION: TFP and NIBUT was age dependent but not gender and race dependent. Older subjects had higher grade of TFP and McMonnies questionnaire score but lower NIBUT value. TFP and NIBUT can be used to assess the tear film quality.