A tube device for forming a fistula is constructed in such a way that the tube device is composed of a metallic guide wire, a small diameter tube to which the guide wire can be inserted in its center, a medium diameter tube covering the outer periphery of the small diameter tube, a medium-large diameter...http://www.google.fr/patents/US4981482?utm_source=gb-gplus-shareBrevet US4981482 - Device for forming an inserting hole for an endoscope
Device for forming an inserting hole for an endoscope
