Healing of perforating rat corneal incisions closed with photodynamic laser-activated tissue glue

Background and Objectives: Laser-activated photodynamic biologic tissue glues may be useful for closing incisions in ophthalmology. We report on the use of two such preparations to close perforating corneal incisions in living rats. Study Design/Materials and Methods: A previously described preparation containing a covalent albuminchlorin e6 (ce6) conjugate (bovine serum albumin (BSA) - ce6), and a novel mixture of albumin and Janus Green (BSA/JG), both activated with a 665-nm diode laser were used to glue mouse skin ex vivo. The optimized glues were then used to seal incisions in rat corneas and results were compared to control incisions. Rats were sacrificed at day 1, 7, and 14 and eyes tested for leaking pressure and examined histopathologically. Results: One day after treatment eyes closed with BSA - ce6 had a leaking pressure (in mmHg) of 357 compared to 193 for control incisions (P<0.01); closure with BSA/JG gave a leaking pressure of 430 (P<0.05 compared to BSA - ce6, and P<0.001 compared to control). Histological examination showed eyes sealed with BSA/JG have less inflammation present than untreated eyes at 7 days. Conclusions: These data demonstrate that photodynamic laser activated tissue glues can be used to effectively seal corneal incisions in living animals without thermal damage or undue inflammation.