Helen Gao: Today, I am presenting our work on bench testing the characteristics of medical adhesives for stone fragment removal. Retained fragments following laser lithotripsy may grow or act as nidi for future stone formation. Aggregation agents have been used to entrap post-lithotripsy fragments for subsequent basket removal, potentially improving stone-free rates. In this study, we evaluated the physical chemical properties of two aggregation agents, MediNik Hydrogel and TISSEEL Sealant. Adhesives were prepared per manufacturer guidelines. To determine tensile strength, a one-centimeter segment of each material was grasped between two NGage baskets. One basket was attached to a force sensor and pulled until the material ruptured. This was performed in quadruplicate. Adhesiveness was defined as the force required to dislodge an embedded 3.0 x 6.0 millimeter calcium oxalate stone from within each material. This was performed in quadruplicate.

Transparency was measured using a lux meter. Solubility was determined by immersing pre-weighed samples of each agent in containers of 37 degrees Celsius saline. The containers were placed on a shaker platform for 48 hours, filtered through a 210 micro-mesh, and any residual agent was weighed in triplicate. MediNik and TISSEEL showed no significant difference in tensile strength. TISSEEL had significantly greater adhesive strength than MediNik. MediNik was more transparent than TISSEEL. MediNik was also more soluble than TISSEEL. In conclusion, TISSEEL had greater adhesive strength than MediNik. MediNik and TISSEEL had similar innate tensile strength. MediNik provided better transparency and solubility. Thank you.