this invention relates a novel surgical device scalable to small dimensions for thermally - mediated treatments or thermoplasties of targeted tissue volumes . an exemplary embodiment is adapted for shrinking , sealing or welding tissue . the instruments and techniques utilize a thermal energy delivery means , for example an electrical energy source , to instantly vaporize a biocompatible fluid media within an electrically insulated instrument body . the altered media is characterized by a a high heat content , and a high exit velocity from the working end both of which characteristics are controlled to hydrate tissue and at the same time denature proteins to shrink , seal , weld or cause any other thermally - mediated treatment of an engaged tissue volume — while causing limited collateral thermal damage and while totally eliminating electrical current flow the engaged tissue volume . the system can further utilize a piezoelectric material that carries fluid channels to apply compressive forces to eject the gas media from the working end of allow a lesser electrical energy requirement to convert a liquid to a gas and to increase media exit pressure .