| 摘要 |
Apparatus and methods are provided for providing access to a body lumen. The apparatus includes a tubular member including a proximal end, a distal end sized for insertion into a body lumen, and a lumen extending therebetween. A pushable stiffening member extends from the distal end of the tubular member. An expandable sheath extends along at least a portion of the stiffening member, the sheath being expandable from a contracted condition to facilitate insertion into a body lumen, and an enlarged condition wherein the sheath at least partially defines a lumen communicating with the tubular member lumen. A distal portion of the sheath is steerable, e.g., using a pull wire disposed within a lumen of the sheath or within the stiffening member. In addition or alternatively, the stiffening member may be biased to a predetermined shape to facilitate introduction.
|
