Methods and devices for protecting a passageway in a body when advancing devices through the passageway

DETAILED DESCRIPTION In accordance with the objects of the invention, a liner is provided to protect a body passageway during introduction of other devices into the passageway.
In a specific application, the methods and devices of the present invention are used to protect blood vessels, such as the internal carotid artery, during intravascular procedures.
It is understood that use of the present invention for protection of blood vessels is discussed as an example of how the present invention may be used, however, the invention may be used in any other part of the body without departing from the scope of the invention.
The liner is collapsed for introduction into the patient and advanced to a narrowed region of a blood vessel.
The liner is passed through a region of the blood vessel in the collapsed condition and an intravascular device, such as a stent or filter, is then introduced into the liner.
The liner may be used to protect vessels from any type of problem including atherosclerotic disease, perforation, aneurysm or AVM.
The liner protects the vessel as the intravascular device is passed through the region to prevent the device from dislodging plaque.
When the device is a stent, the stent is preferably expanded within the liner to trap the liner between the stent and the vessel.
The liner may be expanded by the stent or may be partially or fully expanded before introduction of the stent.
The devices and methods of the present invention are particularly useful for treating occlusive disease of the internal carotid artery.
The liner may be any suitable material and suitable materials include expanded PTFE, woven dacron, nylon, low durometer silicone, or thin-walled polyethylene.
The liner is preferably mounted to a delivery catheter and is advanced over a guidewire.
The liner may have an anchor at a proximal end which is used to open the proximal end of the liner.
The anchor may be self-expanding or balloon expandable.
Once the proximal end of the liner is opened, the liner can be designed so that blood pressure opens the liner