Tear film stability in dry eye syndrome: Time and break‐up patterns

Abstract Purpose: Comparison between traditional invasive methodologies and modern non‐invasive high‐tech methodologies for qualitative and quantitative evaluation in 3 groups of patients with dry eye disease. Methods: Cross sectional study of 111 participants recruited consecutively at the eye clinic of San Giuseppe Hospital in Milan in 3 groups: healthy ( n = 30), aqueous deficient dry eye ADDE) ( n = 32) and evaporative dry eye (EDE) ( n = 49) underwent osmolarity assessment, OSDI questionnaire, tear meniscus height measurement (TMH), Non‐invasive (NIKBUT‐first and NIKBUT‐average) and invasive (FBUT with fluorescein) tear film break up time, Meiboscore, corneal staining and Schirmer test. Results: FBUT, Schirmer test, f‐NIKBUT and a‐NIKBUT were significantly different between the three groups ( p < 0.001). FBUT and also f‐NIKBUT were lower in EDE group (4.46 ± 2.24) than other groups; In healthy and ADDE subjects, tear film break‐up time was located in the lower sector between the periphery average and the extreme. NiKBUT pattern was significantly different between the upper and lower peripheral, nasal and temporal periphery and the central temporal into the different groups ( p < 0.05). Correlation analysis showed an inverse association between age and f‐NIKBUT ( r = −0.358) between all patients. Corneal staining was more severe in ADDE patients. Conclusions: In ADDE group the f‐NIKBUT was higher, almost at normal values, compared to FBUT. In a previous study, NIKBUT was found to be higher than FBUT due to non‐installation of dyes in the eye. In healthy and EDE subjects the tear film rupture was located in the lower sector between the average periphery and the extreme, probably due to a longer exposure time than in other areas. In EDE subjects, however, f‐NIKBUT was found in the central temporal and nasal sectors in according with previous studies. Average and f‐NIKBUT were negatively related with the age and also positively related to each other. FBUT and f‐NIKBUT were related to each other differently in 3 groups of patients; they could study different aspects of the same phenomenon, further studies are ongoing. References 1. Mark D.P. Willcox, Pablo Argüeso, TFOS DEWS II Tear Film Report, Ocular Surface, 2017. 2. Michae L.A. Lemp, The Definition and Classification of Dry Eye Disease, 2007.