Apparatus and method for treating tissue with multiple electrodes

Abstract

A probe system for volumetric tissue heating and ablation comprises a cannula having a multiple electrode component reciprocatably mounted therein. Individual electrodes within the array have spring memory so that they assume a radially outward, arcuate configuration as they are advanced distally from the cannula. Preferably, the electrodes fully evert as they are advanced from the cannula. Prior to deployment, the electrodes are constrained within a lumen of the cannula. The electrodes are maintained with a uniform circumferential spacing by confining them within an annular envelope defined by a core member within the cannula lumen, by providing electrodes having asymmetric cross-sectional geometries, and/or by nesting the electrodes closely together. Optionally, a cutting current may be applied to the electrodes as they are advanced.

Dependencies are inferred from the claim text.