The clinical use of viscoelastic artificial tears and sodium chloride in dry-eye syndrome

This study was performed to test viscoelastic artificial tears (VAT) based on both subjective and clinical parameters in patients with keratoconjunctivitis sicca (KCS). Twenty-eight patients were evaluated in a randomized double-blind study. Sodium hyaluronate was used in two different concentrations (0.4%, 0.25%) and in combination with chondroitin sulfate. Each preparation was used for one week preceded by another weekly cycle using a sodium chloride solution. Before and after each cycle, clinical examinations were performed: tear film break-up time, Schirmerʹs test, lipid-layer thickness and fluorescein staining. Patients kept a record of the drop-frequency, subjective response and side effects. After the study, they were asked to give a rating of the various preparations. The severity of KCS was expressed based on a sicca score and correlated with response to viscoelastic treatment. Both the subjective and the clinical parameters revealed no statistically significant differences between the various viscoelastic agents or between the viscoelastics and the sodium chloride solutions. Severe side effects did not occur. There was a positive correlation of response to viscoelastic treatment with severe KCS (+0.36) but not with mild KCS (−0.07). The VAT seems to be indicated in severe cases of dry-eye syndrome. Sodium chloride solutions may be a useful short-term alternative to other tear formulations.