WO2003061456A3 - Electrosurgical instrument and method of use - Google Patents

Abstract

An electrosurgical medical device and method (Fig. 8A) for creating thermal welds in engaged tissue. In one embodiment, at least one jaw of the instrument defines a tissue engagement plane carrying a conductive-resistive matrix of a conductively-doped non-conductive elastomer. The engagement surface portions thus can be described as a positive temperature coefficient material that has a unique selected decreased electrical conductance at each selected increased temperature thereof over a targeted treatment range. The conductive-resistance matrix can be engineered to bracket a targeted thermal treatment range, for example about 60 °C. to 80 °C., at which tissue welding can be accomplished. In one mode of operation, the engagement plane will automatically modulate and spatially localize ohmic heating within the engaged tissue from Rf energy application-across-micron-scale portions of the engagement surface (155A). In another mode of operation, a conductive-resistive matrix can induce a 'wave' of Rf energy density to sweep across the tissue to thereby weld tissue.