Instrument introducers and methods of using the same are provided to facilitate the introduction of a surgical instrument into a cavity or a body opening of a patient. The instrument introducers include a body portion defining a lumen therethrough, a flexible distal end portion having a distal orifice,...http://www.google.es/patents/US20070051375?utm_source=gb-gplus-sharePatente US20070051375 - Instrument introducer
