Devices and methods for removing obstructive material, from an intravascular site
A neurovascular catheter having an atraumatic navigational tip is disclosed. The catheter includes an elongate flexible tubular body, a distal zone of the tubular body comprising: a tubular inner liner; a helical coil surrounding the inner liner and having a distal end, a tubular jacket surrounding the helical coil, and extending distally beyond the helical coil distal end to terminate in a catheter distal face, and a tubular radiopaque marker embedded in the tubular jacket. The catheter distal face comprises a first section that resides on a first plane which crosses a longitudinal axis of the tubular body at a first angle within the range of from about 35 degrees to about 55 degrees, and a second section that resides on a second plane which crosses the longitudinal axis of the tubular body at a second angle within the range from about 55 degrees to about 90 degrees.
1. A neurovascular catheter having an atraumatic navigational tip, comprising:
an elongate flexible tubular body, having a proximal end, a distal end and a side wall defining a central lumen, a distal zone of the tubular body comprising:
a tubular inner liner,
a helical coil surrounding the inner liner and having a distal end,
a tubular jacket surrounding the helical coil, and extending distally beyond the helical coil distal end to terminate in a catheter distal face,
a tubular radiopaque marker embedded in the tubular jacket in between the distal end of the coil and the distal face,
a first side of the side wall and a second side of the side wall, the first side being opposite the second side, the first side and the second side being generally parallel to a longitudinal axis of the tubular body,
wherein the catheter distal face comprises:
a first section extending from the first side of the side wall and forming a first angle within a range of from about 55 degrees to about 65 degrees relative to the longitudinal axis of the tubular body, and
a second section extending from the second side wall and forming a second angle within a range from about 75 degrees to about 90 degrees relative to the longitudinal axis of the tubular body.
2. A neurovascular catheter as in claim 1 , wherein the marker comprises a marker distal face that forms a third angle within the range of from about 55 degrees to about 65 degrees relative to the longitudinal axis of the tubular body.
3. A neurovascular catheter as in claim 2 , wherein the distal face defines a leading edge of the tubular body which extends distally of a trailing edge of the tubular body, the leading edge and trailing edge spaced about 180 degrees apart from each other around the longitudinal axis.
4. A neurovascular catheter as in claim 3 , wherein an advance segment of the tubular body extends distally beyond the marker.
5. A neurovascular catheter as in claim 4 , wherein the advance segment has an axial length within the range of from about 0.1 mm to about 5 mm on the leading edge of the tubular body.
6. A neurovascular catheter as in claim 3 , wherein an axial length of the marker on the leading edge of the tubular body is at least about 20% longer than the axial length of the marker on the trailing edge of the tubular body.
7. A neurovascular catheter as in claim 6 , wherein the axial length of the marker on the leading edge of the tubular body is within the range of from about 1 mm to about 5 mm.
8. A neurovascular catheter as in claim 3 , wherein the marker comprises at least one axial slit.
9. A neurovascular catheter as in claim 3 , wherein the tubular liner is formed by dip coating a removable mandrel.
10. A neurovascular catheter as in claim 9 , wherein the tubular liner comprises PTFE.
11. A neurovascular catheter as in claim 3 , further comprising a tie layer between the inner liner and the helical coil.
12. A neurovascular catheter as in claim 11 , wherein the tie layer has a wall thickness of no more than about 0.005 inches.
13. A neurovascular catheter as in claim 12 , wherein the tie layer extends along at least a most distal 20 cm of the tubular body.
14. A neurovascular catheter as in claim 3 , wherein the coil comprises Nitinol.
15. A neurovascular catheter as in claim 14 , wherein the Nitinol comprises an Austenite state at body temperature.
16. A neurovascular catheter as in claim 3 , further comprising a tension support for increasing a tension resistance in the distal zone.
17. A neurovascular catheter as in claim 16 , wherein the tension support comprises an axially extending filament.
18. A neurovascular catheter as in claim 17 , wherein the axially extending filament is carried between the inner liner and the helical coil.
19. A neurovascular catheter as in claim 17 , wherein the axially extending filament increases a tensile strength of the tubular body to at least about 2 pounds.
20. A neurovascular catheter as in claim 1 , wherein the tubular jacket is formed from at least five discrete axially adjacent tubular segments.
21. A neurovascular catheter as in claim 20 , wherein the tubular jacket is formed from at least nine discrete axially adjacent tubular segments.
22. A neurovascular catheter as in claim 20 , wherein a difference in durometer between a proximal one of the tubular segments and a distal one of the tubular segments is at least about 20D.
23. A neurovascular catheter as in claim 22 , wherein the difference in durometer between a proximal one of the tubular segments and a distal one of the tubular segments is at least about 30D.