Abstract
Purpose :
To determine whether an association between functional and structural tests of the tear film can be found and to describe if a significant difference between preoperative and postoperative parameters is present.
Methods :
We studied 34 eyes of 17 patients undergoing LASIK surgery. OCT tear film (TF) analysis consisted of structural parameters such as tear meniscus height, depth, and area (RTVue-100 Fourier-domain OCT) and functional tests such as Schirmer, Non-Invasive Tear Breakup Time (NIBUT) (Keratograph 5M), and Ocular Surface Discomfort Index (OSDI). Measurements were performed before and 1 month after the procedure. Wilcoxon test was used to compare basal vs postoperative structural and functional TF parameters. Correlation analysis and linear regression were also implemented to model the association between these variables. A p-value of less than .05 was considered of statistical significance.
Results :
No significant changes between basal and postoperative measurements were observed in the structural and functional TF variables. The analysis yielded a negative correlation (Rho= -0.349, p= 0.043) between basal tear meniscus height and basal NIBUT. A negative correlation between basal tear meniscus height and 1-month postoperative NIBUT (Rho= -0.409, p=.016) and 1-month postoperative Schirmer test (Rho= -0.360, p= .036) was observed. The linear regression model yielded no significant correlation. Change (delta) in basal vs 1-month postoperative NIBUT was associated with age and spherical equivalent (β=.547, p=.028, and β=-.522, p=.016).
Conclusions :
Our analysis did not demonstrate a significant difference between basal vs 1-month measurements in neither structural or functional tests. However, results suggest that Dry Eye Disease can manifest with normal structural TF parameters while yielding altered results in the functional evaluation. More studies are needed in order to determine the presence of significant differences in basal vs longer-term measurements.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.