Abstract
Purpose :
High viscosity lubricants are characterized by a long residency time on the eye, which may require less frequent instillation to protect the ocular surface. The aim of the present study therefore was to compare the effect of artificial tears during the day combined with an artificial tear substitute gel before going to bed to the exclusive use of a high viscous gel on ocular surface parameters in patients with dry eye disease (DED).
Methods :
The study was conducted in a randomized, observer-masked, cross over design in 40 patients with moderate to severe DED. After a washout period, patients received trehalose and hyaluronic-acid based lubricant eye drops (TH-HA, Thealoz Duo® eye drops multi-dose) for use during the day combined with a trehalose, hyaluronic-acid/carbomer based gel (TH+HA/CA, Thealoz Duo® gel unidose) before going to bed, or simply TH-HA/CA only to use as needed. After one week of treatment, another washout period was scheduled and patients crossed over to the other group. Clinical standard tests for DED, such as corneal fluorescein and conjunctival lissamine green staining, measurement of break up time (BUT), Schirmer I test and the Ocular Surface Disease Index (OSDI) questionnaire were performed at the beginning and end of each study period. Instillation frequencies were recorded in a diary.
Results :
Corneal fluorescein and conjunctival lissamine green staining score significantly decreased in both groups (p<0.001 each). In addition, a significant increase in BUT with both treatment regimen was observed (p<0.001). No significant changes in Schirmer I test score or OSDI was observed. Mean instillation frequency was 3.1±2.6 drops/day when using TH-HA during the day and TH-HA/CA before going to bed, and 1.9±2.2 applications/day when only the high viscous gel was used (p=0.02).
Conclusions :
With both treatment regimes, a significant improvement in corneal fluorescein and conjunctival lissamine green staining score as well as in BUT was observed. Instillation frequency was significantly lower when using the high viscous gel alone compared to artificial tears. This might indicate a longer corneal residence time of the TH-HA/CA gel caused by the increased viscosity due to the additional carbomer component of the product.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.