摘要 |
An apparatus for forming and enlarging percutaneous penetrations comprises an elongate dilation tube which receives an elongate expansion member in an axial lumen thereof. The dilation tube is radially expandable from a small diameter configuration to a larger diameter configuration. The dilation tube is percutaneously introduced to a desired target site within a patient's body and thereafter radially expanded by axial insertion of the expansion member through the axial lumen of the tube. The tube prevents the application of axial forces on the surrounding tissue as the expansion member is introduced. The expansion member may include a separate outer sleeve member which remains in place to maintain the enlarged access channel. Optionally, an inflatable balloon at the distal end of the dilation tube may be provided to enhance retention of the device and sealing of the penetration. |