A link between tear breakup and symptoms of ocular irritation

TitleA link between tear breakup and symptoms of ocular irritation
Publication TypeJournal Article
Year of Publication2017
AuthorsZhang, J., C. G. Begley, P. Situ, T. Simpson, and H. Liu
JournalOcular Surface
Keywordsadult, Article, blinking, contact lens, Contact lenses, controlled study, Cornea, Dry eye, Dry eye symptoms, Dry Eye Syndromes, eye discomfort, eye irritation, female, human, human experiment, Humans, Hydrophilic, hydrophilic contact lens, lacrimal fluid, male, nociceptive stimulation, normal human, Sensory response, symptomatology, Tear breakup, Tear film instability, tear flow, Tears
Abstract{Purpose We used the presence or absence of a soft contact lens (CL) as a barrier to test the hypothesis that tear breakup (TBU) presents a direct noxious stimulus to the ocular surface. Methods Ten subjects kept one eye open as long as possible, termed sustained tear exposure (STARE), for 10 consecutive trials while discomfort was monitored with and without a CL in place. The area of TBU was quantified in each frame. Discomfort was measured during and after each STARE trial and symptoms of ocular irritation were assessed before and after all testing. Results TBU increased at the end of trials to an average of 19.89% ± 17.91% and 20.58% ± 15.33% and discomfort to 9.09 ± 1.44 and 1.97 ± 2.19 in trials without and with a CL, respectively. Discomfort was significantly higher during trials without CLs (Friedman test, p < 0.005), but there was no significant difference in the area of TBU between trials (Friedman test