Abstract: Apparatus and methods are provided for placing an introducer sheath into a subcutaneous tissue region, such as a prostate, e.g., to facilitate insertion of a cryogenic probe. In one embodiment, a dilation apparatus is provided that includes an introducer sheath containing a dilator that, in turn, contains a stylet. A pointed tip of the stylet is inserted into a patient's skin and the dilator is advanced over the inserted stylet to dilate surrounding tissue. The introducer sheath is then advanced over the dilator through the tissue to provide access to a target tissue region, such as the prostate. The stylet and dilator are removed from the introducer sheath, leaving the introducer sheath in place. A cryogenic probe may be inserted into the introducer sheath, and may be coupled to a cryosurgical system, e.g., to ablate or otherwise treat the target tissue region.

Abstract: An improved electrode for use in medical procedures requiring tissue removal. At least one gear shaped element is provided and mounted onto a distal tip region of a wire loop electrode. The gear shaped element distributes current at a tissue/electrode interface and enables the electrode to cut through substantial quantities of tissue while simultaneously creating a substantial rim of coagulation within an area of cut tissue.