TITLE : Sealing penetrating eye injuries with photoactivated bonding PRINCIPAL INVESTIGATOR : Irene

Platform presentation at 2011 ATACCC Conference, Fort Lauderdale FL, August 15-18,2011 Sealing Penetrating Eye Injuries Using Photoactivated Bonding A.J. Johnson, E.E. Verter, T. Gisel, P. Yang, R.W. Redmond, I.E. Kochevar Objective: To rapidly seal irregular-shaped penetrating wounds in cornea and sclera with lessscarring, better visual outcomes and reduced OR time requirement. Background: Closure of penetrating eye wounds with sutures is a time-consuming procedurethat produces scarring and consequent poor visual outcome. We have developed a tissue repairtechnology (PTB) that bonds tissue surfaces together using a dye and green light. Light-activationof the dye cross-links proteins to bridge the tissue surfaces thus producing a water-tight seal.PTB has been used successfully in a clinical study for superficial wound closure and in preclinicalstudies for reattachment of peripheral nerves, blood vessel anastomosis and tendon repair. In thisstudy,PTB was used to seal human amniotic membrane (HAM) over penetrating cornea wounds. Methods: A HAM patch (13-mm diameter) was stained on the stromal side with Rose Bengal(RB) and placed over a V-shaped incision in de-epithelialized central cornea. A 4-mm opaquedisc was placed over the incision before green light treatment (532 nm KTP laser). The strengthof the seal was measured by infusing saline into the anterior chamber and measuring thepressure that produced leakage(IOPL). Results: Sealing HAM over cornea wounds in rabbit eyes produced IOPL significantly higherthan the normal IOP. Bonding with 0.1% RB and 150 J/cm at 532 nm produced an IOPL of 448mm ± 212 mm Hg in vivo. Bonding ex vivo eyes showed that the IOPL increased with increasingfluence (50-150 J/cm; 3.3 to 10 min); the IOPL attained over this range was 95 to 261 mm Hg.HAM sutured over the wound produced an IOPL of 20 mm Hg. A small temperature increase wasobserved, from room temperature to 36°C, during ex vivo bonding. Equivalent IOPL was producedfor bonding basement membrane or stromal HAM surfaces to the cornea surface. Conclusions: These results indicate that PTB may be a useful clinical approach for rapidsutureless sealing of penetrating eye injuries.