A medical device for endoscopic access of a body cavity and a method of percutaneously placing inner and outer access sheaths of the device into the body cavity. The medical device includes inner and outer access sheaths and a dilator which is inserted into the outer sheath and has a shoulder or a shoulder...http://www.google.es/patents/US5112308?utm_source=gb-gplus-sharePatente US5112308 - Medical device for and a method of endoscopic surgery
Medical device for and a method of endoscopic surgery
