Impact of Hyaluronic Acid-Containing Artificial Tear Products on Reepithelialization in an In Vivo Corneal Wound Model

Purpose: To evaluate the effect of 6 commercially available hyaluronic acid (HA)-containing topical artificial tear products on corneal reepithelialization following injury, in an in vivo mouse model. Methods: Ninety-six C57Bl/6 mice (16 per treatment group; male to female ratio, 1:1 per group) were anesthetized. Epithelial debridement was performed on 1 cornea per animal, and the debrided eye was imaged. A 30L masked test solution containing 1 of 6 artificial tear products was instilled, immediately on debridement, and subsequently, every 2h, for a total of 4 administrations. At 24h post debridement, corneas were stained with fluorescein and imaged to calculate corneal healing rate (number of fluorescein-negative corneas). Results: All 6 artificial tear products used in this study permitted the initial process of corneal wound healing. However, the corneal reepithelialization rate after 24h was higher with Hydroxypropyl guar (HPG)/HA (53.33%) compared with other HA-containing artificial tear products [HA1 (12.5%), HA2 (26.67%), HA3 (31.25%), HA4 (6.25%), and HA5 (43.75%)]. The average area and percentage area of reepithelialization after 24h were also higher with HPG/HA compared with other treatment groups. Conclusions: Percentage of eyes with complete corneal reepithelialization 24h post debridement was highest with HPG/HA compared with other HA-containing artificial tear products tested. The results of this study provide additional evidence on the potential benefits of HPG/HA in the management of dry eye and its role in the rapid restoration of a healthy ocular epithelium. However, further studies are required to confirm the effects on human corneal wounds.