Patent ID: 6030379
Filing Date: 2000-02-29
Classification: A61B,A61N

Abstract:
A system for ablating body tissue comprisingan ablation electrode having a thermal mass, the ablation electrode having a tissue contact region for contacting a tissue surface, the ablation electrode adapted to be connected to a source of radio frequency energy to conduct radio frequency energy for transmission by the ablation electrode into the tissue surface contacting the tissue contact region, the ablation electrode including an interior well in the tissue contact region,a tissue temperature sensing assembly carried within the interior well comprising a temperature sensor, a cap enclosing the temperature sensor, the cap being made of a thermal conductive material, which is in thermal conductive contact with the temperature sensor, the thermal conductive material having a thermal conductivity that is at least 1.0 W/m K, and an insulating barrier made of thermal insulating material in the interior well to substantially thermally isolate the cap from the thermal mass of the ablation electrode, the cap having a distal end,a mechanism attached to the cap to selectively move the cap in the interior well to locate the distal end of the cap beyond the tissue contact region of the ablation electrode and into thermal conductive contact with tissue at different distances beneath the tissue surface, the thermal conductive material of the cap reaching thermal equilibrium with tissue temperature conditions without dissipation by the termal mass of the ablation electrode, anda controller coupled to the mechanism and to the temperature sensor to control movement of the cap in the interior well based, at least in part, upon tissue temperature conditions sensed by the temperature sensor within the cap.