Bioadhesives for intraocular use

Background/Purpose: A safe, effective adhesive could be useful in the manag ement of retinal holes or tears and selected complicated retinal detachment s, as well as for attaching a small electronic device (retinal prosthesis) to the retina. In this study, we examined nine commercially available compo unds for their suitability as intraocular adhesives. Methods: The following materials were studied: commercial fibrin sealant, a utologous fibrin, Cell-Tak, three photocurable glues, and three different p olyethylene glycol hydrogels. An electronic strain gauge measured the adher ence forces between different glues and the retina. The stability of hydrog els at body temperature and the impermeability of the hydrogel adhesive to dextran blue were examined. Long-term biocompatibility testing of the most promising glues in terms of adhesive force, consistency, and short-term saf ety (hydrogels) were done in rabbits. Funduscopy, electroretinogram, and hi stology of the retina were performed. Results: Hydrogels had 2 to 39 times more adhesive force (measured in mN) t han the other glues tested. They liquefied at body temperature after 3 days to a few months. Hydrogels were impermeable to dextran blue. One type of h ydrogel proved to be nontoxic to the retina. Conclusions: Hydrogels proved to be superior for intraocular use in terms o f consistency, adhesiveness, stability, impermeability, and safety.