A method for extracting a tissue sample includes altering the pressure inside the lumen of a cannula to facilitate extraction of a tissue sample from the cannula. One aspect of the invention includes a biopsy apparatus comprising a valve for controlling the pressure inside the lumen of the cannula. In...http://www.google.co.uk/patents/US20060173377?utm_source=gb-gplus-sharePatent US20060173377 - Quick cycle biopsy system
