| 摘要 |
This invention is a surgical device. In particular, it is a catheter suitable for accessing a tissue target within the body, typically a target which is accessible through the vascular system. Central to the invention is the use of at least pair of wound or counterwound reinforcing members situated within the wall of the catheter body in such a way to achieve a catheter having an exceptionally thin wall, excellent kink-resistance, and controlled stiffness. The catheter assembly desirably is constructed of: (a) an inner, polymeric, lubricious liner, (b) a first, helically wound coil extending over at least the more distal portions of the inner liner but preferably for most of the length of the catheter, (c) a second, helically wound coil exterior to the first coil, located at least on the more proximal portion of the assembly but preferably for most of the length of the catheter, preferably wound in a direction opposite to the first coil, (d) optionally, one or more helically wound coils placed on the proximal and mid-section of the assembly, and (e) one or more polymeric layers variously exterior to the second coil and interior to the first coil. Preferably, the coils are wound from metallic ribbons or wireshaving a relatively constant pitch of from 10 DEG -15 DEG of the central catheter axis. Further polymeric layers may also be placed between the outer polymeric covering and various and the helically wound coils. The outer polymeric covering may be composed of a series of different polymeric compositions to provide suitably differing flexibilities along the length of the assembly. The catheter assembly is quite easy to produce. The helically wound coils may be bound to the assembly via the use of radio-opaque bands or coils and may be continuously wound from a single member. The distal-most portion of the catheter assembly is very flexible but highly kink resistant. Optionally, the invention includes a catheter in which only the more distal catheter section incorporates multiple coil stiffener members.
|
