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.

主权项

1. A radiofrequency tissue ablation device comprising:
an elongate outer cannula including a cannula proximal end, a cannula distal end, and a cannula intermediate length between the proximal end and distal end, where a longitudinal region of the intermediate length near the distal end is configured as an ablation electrode and including a cannula lumen extending longitudinally through the length of the cannula; and an elongate stylet extending slidably through the cannula lumen and secured to the cannula between the ablation electrode and the cannula distal end; where the ablation electrode includes a plurality of substantially parallel helical apertures disposed around a circumference of the outer cannula, the apertures extending through the cannula; where the ablation electrode is circumferentially expandable such that
in a first state, when the distal cannula end is disposed at a maximum device-length distance from the proximal cannula end, the outer cannula is essentially cylindrical with a substantially uniform outer diameter along substantially its entire length; andin a second state, when the stylet and the secured cannula distal end are less than a maximum device-length distance from the proximal cannula end, the substantially parallel helical apertures of the ablation electrode are expanded and intervening portions of the cannula form an outer diameter greater than the outer diameter of cannula portions proximal of and distal of the ablation electrode.