VARIABLE DIAMETER SHEATH APPARATUS FOR USE IN BODY PASSAGES

摘要

A tubular sheath for insertion into a body passage through a reduced diameter access port and expansion to a diameter exceeding that of the access port after introduction into the passage. The sheath is fabricated of an elastomeric material and, when stretched, reduces to an outside diameter significantly less than that of the inside diameter of the body passage. An elongated stylet is extended through the sheath and engaged with the distal portion adjacent the open end thereof to stretch the sheath as it is inserted into a body passage. The elastomeric construction enables an oversized object received within the expanded end portion to be drawn through portions of the sheath of a nominal diameter less than the object.