SODIUM HYALURONATE EYEDROPS ENHANCE TEAR FILM STABILITY

Sodium hyaluronate eyedrops can relieve various dry eye symptoms by pr olonging the stability of the precorneal tear film. To determine the m ost effective concentration of sodium hyaluronate, we studied the conc entration-dependent effects of sodium hyaluronate eyedrops on the prec orneal tear film breakup time (BUT) in 12 volunteers. These subjects h ad a BUT of 10 seconds or less and a low tear volume determined with t he phenol red thread test. They received four different concentrations of sodium hyaluronate eyedrops (0, 0.05, 0.1 and 0.3%). BUT was measu red noninvasively using a non-contact specular microscope before the s odium hyaluronate eyedrop instillation and again after 5, 15, 30, 60, 120 and 180 minutes. The tear film stability period was prolonged sign ificantly with 0.1% and 0.3% eyedrops at all measurement times (P<0.05 ), while the eyes treated with 0% and 0.05% eyedrops showed no signifi cant prolongation of tear film stability at any measurement times. The findings of this study confirm that sodium hyaluronate at a concentra tion of at least 0.1% is required to delay the breakup of the precorne al tear film.