1. US20090306656 - Therapy apparatus for thermal sclerosing of body tissue

The application arrangement according to the invention for applying a high frequency current for thermal sclerosing of body tissue, includes:

• • an electrode needle 1 having an electrically conducting shaft 3,
  • at least one insulating casing body 7 which surrounds the electrically conducting shaft 3 and which is displaceable relative to the shaft 3 and which has a distal end from which the shaft 3 can be extended, and
  • at least one trocar 5 having a portion intended to be introduced into body tissue, a portion 11 intended to remain outside the body tissue, and a lumen 13 which extends through both portions and through which the shaft 3 of the electrode needle 1 is to be passed through the trocar 5.

The application arrangement according to the invention is distinguished in that the portion of the trocar 5 intended to be introduced into body tissue is electrically insulating and, in particular when the electrode needle or shaft 3 is passed through the lumen, forms the casing body 7 for the shaft 3 of the electrode needle 1.

The trocar 5 performs two functions. On the one hand it performs the conventional tasks of a trocar 5, more specifically for example permitting accurately targeted feed of drugs or removal of tissue and the introduction of electrode needles 1 without having to make a fresh puncture each time. On the other hand the part of the trocar 5 which is in the body serves as an insulating casing body 7 displaceable relative to the shaft 3 of the electrode needle 1 for adjusting the length of the active region of the shaft 3, that is to say that region which projects out of the insulating casing body 7 and is in electrically conductive contact with the body tissue when the electrode needle 1 is inserted into the body.