ENDOSCOPIC ULTRASOUND ABLATION NEEDLE

摘要

A radiofrequency tissue ablation device includes an elongate outer cannula having proximal and distal ends and an intermediate length therebetween where a longitudinal region of the intermediate length is configured as an ablation electrode. A cannula lumen extends longitudinally through the cannula. A stylet extends slidably through the lumen and is secured to the cannula between the ablation electrode and the cannula distal end. The ablation electrode includes a plurality of substantially parallel helical apertures disposed around and extending through a cannula circumference. The ablation electrode is configured to be circumferentially expandable such that in a first state, it is essentially cylindrical with a substantially uniform outer diameter along substantially its entire length, and in a second state, its parallel helical apertures are expanded such that the intervening portions of the cannula form an outer diameter greater than the outer diameter of cannula portions proximal and distal of the electrode.