Assessment of Tear Break-Up Time in Eyes with Encroached Pterygium

Abstract

Pterygium is a frequent disease of the ocular surface characterised by the proliferation of fibrovascular tissue from the bulbar conjunctiva over the limbus to the corneal surface. In addition to affecting look of the eye and vision, pterygium may also disturb the tear film and lead to ocular surface pain and dry eye symptoms. Tear break-up time (TBUT) is an important clinical parameter for evaluation of tear film stability. The present study measured tear break-up time in encroached pterygium patients and compared the data with the patients without pterygium. The study included 100 subjects; 50 cases with encroached pterygium and 50 controls. The stability of the tear-film was evaluated using the fluorescein tear break-up time test. The data were analysed using SPSS version 25.0. Independent-samples t-test was used to compare TBUT between pterygium and control groups. P-value <0.05 was considered statistically significant. Participants were 20–62 years old, mean age was 33 ± 10.42 years. The mean TBUT was decreased in study subjects with encroached pterygium compared to controls (15.00 ± 5.32 seconds vs 25.56 ± 8.12 seconds). Unstable tear film (TBUT ≤ 10 seconds as assessed in this study) was detected in 32% of eyes with encroached pterygium compared to 10% in the control group. The pterygium group was composed of 64% males and 36% females. An independent-samples t-test revealed a statistically significant drop in TBUT in patients with encroached pterygium compared to controls (p < 0.05). Eyes with encroached pterygium had significantly lower tear-film stability than control eyes. The data imply that pterygium may be related with tear film malfunction and greater sensitivity to dry eye symptoms. Increased awareness of pterygium, careful evaluation of the ocular surface and use of lubricating eye drops where clinically warranted may help to enhance ocular comfort in the affected persons