Occlusion device and method of use
A device for protecting cerebral vessels or brain tissue during treatment of a carotid vessel includes a catheter having a distal portion, a proximal portion and a lumen extending therebetween, the catheter including first and second expandable areas for vessel occlusion provided over the length of the catheter. The device further includes an elongate stretching member insertable longitudinally through the lumen of the catheter, the elongate stretching member being configured for stretching at least a portion of the catheter and causing the first and second expandable areas to transition from an expanded state to a collapsed state, and wherein the elongate stretching member is retracted proximally relative to the catheter causes the first and second expandable areas to transition from the collapsed state to a radially, or laterally expanded state.
1. A method for treating a defect in bifurcated vasculature having a common blood vessel and at least first and second branch blood vessels, said method comprising the steps of:
A) providing or obtaining a system that comprises;
i) an elongate, flexible catheter having a proximal expandable area, a distal expandable area, an elongate member receiving lumen, and a treatment device outlet opening, said proximal expandable area being self-expandable from an elongated radially collapsed configuration to a large diameter expanded configuration, said distal expandable area being self- expandable from an elongated radially collapsed configuration to a large diameter expanded configuration; and
ii) an elongate member having a guidewire lumen extending longitudinally therethrough, said elongate member being is a) insertable into the elongate member receiving lumen, b) advanceable to a distal position whereby it engages a portion of the elongate flexible catheter and causes both the proximal and distal expandable areas to assume elongated radially collapsed configurations and thereafter c) retractable to a proximal position whereby it disengages from the portion of the elongate flexible catheter and allows both the proximal and distal expandable areas to assume non-elongated radially expanded configurations;
advancing the catheter over a guidewire which extends through the guidewire lumen of the elongate member, while maintaining the elongate member in the distal position to maintain the proximal and distal expandable areas in their elongated radially collapsed configurations;
B) with the elongate member advanced to a position where it causes both the proximal and distal expandable areas to be in their elongated and radially collapsed configurations, advancing the catheter over the guidewire which extends through the guidewire lumen of the elongate member to a position where the proximal expandable area is in the lumen of the common blood vessel and the distal expandable area is in the lumen of the first branch blood vessel, with the second branch blood vessel emanating from a location between the proximal and distal expandable areas;
C) retracting the elongate member to the proximal position a position whereby it allows both the proximal and distal expandable areas to assume non-elongated radially expanded configurations such that the proximal expandable area contacts the common blood vessel wall and the distal expandable area contacts the first branch blood vessel wall;
D) advancing a treatment device through the elongate member receiving lumen, out of the treatment device outlet opening and into the lumen of the second branch blood vessel; and
E) using the treatment device to perform or facilitate performance of a treatment of a defect in the second branch blood vessel.
2. A method according to claim 1 wherein the treatment device comprises a guidewire that is used to facilitate advancement of another treatment apparatus into the lumen of the second branch blood vessel for treatment of the defect.
3. A method according to claim 1 wherein blood flow through the common blood vessel is normally in an antegrade direction that runs from the proximal expandable region toward the distal expandable region and wherein the proximal expandable region is constructed to occlude blood flow in the antegrade direction, thereby resulting in retrograde backflow of blood in the common blood vessel and second branch vessel toward the proximal expandable area.
4. A method according to claim 3 wherein an opening is formed in the catheter such that the retrograde backflow of blood and any matter contained therein will enter the opening in the catheter and may be aspirated through that opening into a lumen of the catheter.
5. A method according to claim 4 further comprising the step of aspirating blood and any matter contained therein through the opening and into the elongate member receiving lumen of the catheter.
6. A method according to claim 4 wherein at least a distal aspect of the proximal expandable area is blood-permeable and said opening in the catheter is formed within the proximal expandable area so that blood may flow in the retrograde direction through the distal aspect of the proximal expandable area and into the opening in the catheter.
7. A method according to claim 4 further comprising the step of delivering radiographic contrast media into the blood vessels and obtaining an image of the blood vessels.
8. A method according to claim 1 wherein: the treatment device outlet opening is located within the proximal expandable area; the proximal expandable area, when in its expanded configuration, has at least one opening though which the treatment device is passable; and Step D comprises advancing the treatment device through the elongate member receiving lumen, out of the treatment device outlet opening, through an opening in the proximal expandable area and into the lumen of the second branch blood vessel.
9. A method according to claim 1 wherein at least a distal portion of the proximal expandable area is formed of a mesh which, when the proximal expandable area is in its expanded configuration, has a plurality of openings therein and wherein the treatment device is advanced through an opening in that mesh.
10. A method according to claim 1 wherein the common blood vessel is the Common Carotid Artery, the first branch blood vessel is the External Carotid Artery and the second branch blood vessel is the Internal Carotid Artery.