System and methods for shunting fluid
Systems and methods are provided herein that generally involve shunting fluid, e.g., shunting cerebrospinal fluid in the treatment of hydrocephalus. Self-cleaning catheters are provided which include split tips configured such that pulsatile flow of fluid in a cavity in which the catheter is inserted can cause the tips to strike one another and thereby clear obstructions. Catheters with built-in flow indicators are also provided. Exemplary flow indicators include projections that extend radially inward from the interior surface of the catheter and which include imageable portions (e.g., portions which are visible under magnetic resonance imaging (MRI)). Movement of the flow indicators caused by fluid flowing through the catheter can be detected using MRI, thereby providing a reliable indication as to whether the catheter is partially or completely blocked. Systems and methods for flushing a shunt system are also disclosed herein, as are various systems and methods for opening auxiliary fluid pathways through a shunt system.
1. A catheter, comprising:
a main body defining a fluid lumen therein;
an end portion extending from a distal end of the main body, the end portion having:
a distal segment that includes a primary hole through which fluid external to the catheter can enter the fluid lumen; and
a proximal segment that includes an auxiliary hole and a recess formed in an exterior surface of the proximal segment, wherein the auxiliary hole is initially blocked by a membrane and configured to be forced open to allow fluid external to the catheter to enter the fluid lumen through the auxiliary hole; and
a stiffening sleeve disposed over the proximal segment and seated in the recess, the stiffening sleeve having an opening that is aligned with the auxiliary hole.
2. The catheter of claim 1 , wherein the stiffening sleeve is seated in the recess such that the stiffening sleeve and the main body define a continuous smooth outer surface.
3. The catheter of claim 1 , wherein the end portion includes a bullet-tip plug that seals a terminal distal end of the end portion.
4. The catheter of claim 1 , wherein the membrane is disposed over an exterior surface of the catheter.
5. The catheter of claim 1 , wherein the membrane is stretched across the auxiliary hole and attached to the catheter under tension.
6. The catheter of claim 1 , wherein the membrane is thermally welded to the catheter.
7. The catheter of claim 1 , wherein the membrane is coupled to the catheter using one or more O-rings disposed around the membrane and the catheter.
8. The catheter of claim 1 , wherein the proximal segment includes a plurality of auxiliary holes, each having a membrane stretched in a different direction.
9. The catheter of claim 1 , wherein the stiffening sleeve is disposed over the membrane.
10. The catheter of claim 1 , wherein the membrane comprises radiopaque material.
11. The catheter of claim 10 , wherein the radiopaque material is printed on the membrane.
12. The catheter of claim 10 , wherein the radiopaque material comprises a thin ribbon.
13. The catheter of claim 10 , wherein the radiopaque material is held in place by the stiffening sleeve.
14. The catheter of claim 10 , wherein the radiopaque material comprises a wire extending longitudinally across the auxiliary port.
15. The catheter of claim 14 , wherein the wire is looped back and forth multiple times over the auxiliary port.
16. The catheter of claim 1 , further comprising an antenna that resonates when excited with RF energy, the antenna being disposed over the membrane and configured to bend or break when the auxiliary hole is forced open.
17. The catheter of claim 1 , wherein the distal segment includes a plurality of primary holes spaced along a length of the distal segment and about a circumference of the distal segment.
18. The catheter of claim 1 , further comprising a flusher in fluid communication with the catheter, the flusher being configured to emit a pulse of fluid to force the auxiliary hole open.
19. A catheter, comprising:
a tubular body that defines a fluid lumen;
a primary hole through which fluid external to the catheter can enter the fluid lumen;
an auxiliary hole that is initially blocked and configured to be forced open to allow fluid external to the catheter to enter the fluid lumen through the auxiliary hole;
a recess formed in an exterior surface of the body, the recess surrounding a raised portion of the body in which the auxiliary hole is formed; and
a stiffening sleeve disposed within the recess, the stiffening sleeve having an opening in which the raised portion is received.
20. A catheter, comprising:
a proximal segment that defines a fluid lumen therethrough;
a first intermediate segment disposed at a distal end of the proximal segment, the first intermediate segment having an auxiliary hole that is initially blocked by a membrane and configured to be forced open to allow fluid external to the catheter to enter the fluid lumen through the auxiliary hole, the first intermediate segment further having a recess in which a stiffening sleeve is disposed, the stiffening sleeve having an opening that is aligned with the auxiliary hole;
a second intermediate segment disposed at a distal end of the first intermediate segment, the second intermediate segment having a plurality of primary holes through which fluid external to the catheter can enter the fluid lumen; and
a distal segment disposed at a distal end of the second intermediate segment, the distal segment comprising a bullet-tip plug that seals a terminal distal end of the catheter.