Abstract
Purpose :
Emerging literature points to a link between ocular surface disorders and air pollution. However, the severity of these disorders may depend on the duration of exposure and concentration and types of air pollutants, i.e. the mixture of airborne particulate matter (PM) and gases. This research examines the viability, size and composition of PM harvested from the ocular surface of Miami veterans in two different environments (home and eye clinic) and their association with dry eye symptoms and signs.
Methods :
PM was harvested using Schirmer strips from individuals while they were at home and in the eye clinic approximately 3 days apart. Strips were analyzed using scanning electron microscopy (SEM) and the energy dispersive spectroscopy (EDS) tool for particle types (organic versus inorganic) and elemental composition. The stability of particles was evaluated using paired t test methodologies. Correlations between detected particles and environmental and clinic metrics were assessed using correlation coefficients.
Results :
Mean age of the 12 patients was 56.33 ± 11.72 years, 93% were male, and 53% self-identified as white. A higher area of organic and inorganic particles were detected from Schirmer strips collected in the clinic than home but the difference was not statistically significant (total area of particles: home 2940.56±4016.51, clinic 7615.20±1895, p=0.48). A similar trend appeared with respect to aluminum, gold, calcium, chloride and silica in the clinic vs home environment. Total area of particles found on the ocular surface significantly correlated with indoor temperature (rho=-0.53, p=0.06) and with several dry eye signs: tear osmolarity (rho= -0.60, p=0.02), inflammation (rho=0.53, p=0.04) and TBUT (rho=0.56, p=0.03).
Conclusions :
Particles could be detected from Schirmer strips and quantified by sub-type. Higher particle area detected on Schirmer strips correlated with inflammation detected on the ocular surface.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.