A tissue acquisition system includes electrodes that are energized by a radio frequency (RF) energy source. Retractable electrodes are energized and extended from a cannula and the cannula is advanced in the tissue to position the cannula near the target tissue site in a patient. The retractable electrodes...http://www.google.co.uk/patents/US6517498?utm_source=gb-gplus-sharePatent US6517498 - Apparatus and method for tissue capture
