A marking device according to one embodiment of the invention comprises a handle, a cannula having a cannula distal end and slidably mounted to the handle, and a stylet having a stylet distal end and slidably mounted to the handle in the cannula. The stylet distal end is spaced proximally of the cannula...http://www.google.es/patents/US20060241411?utm_source=gb-gplus-sharePatente US20060241411 - MARKING DEVICE WITH RETRACABLE CANNULA
