U.S. patent application number 12/894111 was filed with the patent office on 2012-03-29 for multi-lumen ventricular drainage catheter.
This patent application is currently assigned to CODMAN & SHURTLEFF, INC. Invention is credited to Emilie Neukom, Stephen F. Wilson.
Application Number | 20120078159 12/894111 |
Document ID | / |
Family ID | 44785513 |
Filed Date | 2012-03-29 |
United States Patent
Application |
20120078159 |
Kind Code |
A1 |
Wilson; Stephen F. ; et
al. |
March 29, 2012 |
MULTI-LUMEN VENTRICULAR DRAINAGE CATHETER
Abstract
A shunt includes a housing having an inlet, an outlet and a flow
control mechanism disposed within the housing. A ventricular
catheter is connected to the inlet of the housing. The catheter has
a longitudinal length, a proximal end, a distal end, and an inner
lumen extending therethrough. The inner lumen of the catheter
includes at least two lumens at the distal end and has only one
lumen at the proximal end. The catheter has one slit and aperture
corresponding to each of the at least two lumens located at the
distal end of the catheter.
Inventors: |
Wilson; Stephen F.; (North
Easton, MA) ; Neukom; Emilie; (Zug, CH) |
Assignee: |
CODMAN & SHURTLEFF, INC
Raynham
MA
|
Family ID: |
44785513 |
Appl. No.: |
12/894111 |
Filed: |
September 29, 2010 |
Current U.S.
Class: |
604/9 ;
604/523 |
Current CPC
Class: |
A61M 2210/0693 20130101;
A61M 27/006 20130101; A61M 25/007 20130101; A61M 25/0071 20130101;
A61M 2205/04 20130101 |
Class at
Publication: |
604/9 ;
604/523 |
International
Class: |
A61M 1/00 20060101
A61M001/00; A61M 25/00 20060101 A61M025/00 |
Claims
1. A shunt comprising: a housing having an inlet, an outlet and a
flow control mechanism disposed therein; a catheter connected to
the inlet of the housing, the catheter having a longitudinal
length, a proximal end, a distal end, and an inner lumen extending
therethrough, the inner lumen of the catheter being comprised of at
least two lumens at the distal end and being comprised of only one
lumen at the proximal end, the catheter having an aperture adjacent
to the distal end corresponding to each of the at least two
lumens.
2. The shunt according to claim 1, wherein each aperture has an
enlarged opening at the distal end and transitions from the
enlarged opening to a tapering slit at the proximal end of the
aperture.
3. The shunt according to claim 2, wherein a portion of each
aperture between the enlarged opening and the tapering slit is a
slit of constant thickness.
4. The shunt according to claim 3, wherein the enlarged opening of
each aperture has a smooth concave inner surface.
5. The shunt according to claim 1, wherein the enlarged opening of
each aperture has a smooth concave inner surface.
6. The shunt according to claim 1, wherein the inner lumen of the
catheter being comprised of at least three lumens at the distal
end.
7. The shunt according to claim 6, wherein the inner lumen of the
catheter being comprised of at least four lumens at the distal
end.
8. The shunt according to claim 1, wherein the catheter has only
one aperture adjacent to the distal end corresponding to each of
the at least two lumens.
9. A shunt comprising: a housing having an inlet, an outlet and a
flow control mechanism disposed therein; a catheter connected to
the inlet of the housing, the catheter having a longitudinal
length, a proximal end, a distal end, and an inner lumen extending
therethrough, the inner lumen of the catheter having an aperture
that has an enlarged opening at the distal end and transitions from
the enlarged opening to a tapering slit at the proximal end of the
aperture.
10. The shunt according to claim 9, wherein a portion of each
aperture between the enlarged opening and the tapering slit is a
slit of constant thickness.
11. The shunt according to claim 9, wherein the enlarged opening of
each aperture has a smooth concave inner surface.
12. The shunt according to claim 9, wherein the enlarged opening of
each aperture has a smooth concave inner surface.
13. The shunt according to claim 9, wherein the inner lumen of the
catheter being comprised of at least three lumens at the distal
end.
14. The shunt according to claim 13, wherein the inner lumen of the
catheter being comprised of at least four lumens at the distal
end.
15. The shunt according to claim 9, wherein catheter has only one
aperture adjacent to the distal end thereof
16. The shunt according to claim 9, wherein catheter has at least
two apertures adjacent to the distal end thereof
17. A ventricular catheter comprising: the ventricular catheter
having a longitudinal length, a proximal end, a distal end, and an
inner lumen extending therethrough, the inner lumen of the catheter
being comprised of at least two lumens at the distal end and being
comprised of only one lumen at the proximal end, the catheter
having only one aperture adjacent to the distal end corresponding
to each of the at least two lumens.
18. The ventricular catheter according to claim 17, wherein each
aperture has an enlarged opening at the distal end and transitions
from the enlarged opening to a tapering slit at the proximal end of
the aperture.
19. The ventricular catheter according to claim 18, wherein a
portion of each aperture between the enlarged opening and the
tapering slit is a slit of constant thickness.
20. The ventricular catheter according to claim 17, wherein the
enlarged opening of each aperture has a smooth concave inner
surface.
21. The ventricular catheter according to claim 17, wherein the
enlarged opening of each aperture has a smooth concave inner
surface.
22. The ventricular catheter according to claim 17, wherein the
inner lumen of the catheter being comprised of at least three
lumens at the distal end.
23. The ventricular catheter according to claim 22, wherein the
inner lumen of the catheter being comprised of at least four lumens
at the distal end.
24. A ventricular catheter comprising: the ventricular catheter
having a longitudinal length, a proximal end, a distal end, and an
inner lumen extending therethrough, the catheter having an aperture
that has an enlarged opening at the distal end and transitions from
the enlarged opening to a tapering slit at the proximal end of the
aperture.
25. The ventricular catheter according to claim 24, wherein a
portion of each aperture between the enlarged opening and the
tapering slit is a slit of constant thickness.
26. The ventricular catheter according to claim 24, wherein the
enlarged opening of each aperture has a smooth concave inner
surface.
27. The ventricular catheter according to claim 24, wherein the
enlarged opening of each aperture has a smooth concave inner
surface.
28. The ventricular catheter according to claim 24, wherein the
inner lumen of the catheter being comprised of at least three
lumens at the distal end.
29. The ventricular catheter according to claim 29, wherein the
inner lumen of the catheter being comprised of at least four lumens
at the distal end.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to a shunt and a
catheter having a system for reducing the risk of blockage or
obstruction of the catheter apertures and also increases the ease
of revision surgery if the catheter is removed.
BACKGROUND OF THE INVENTION
[0002] Hydrocephalus is a neurological condition that is caused by
the abnormal accumulation of cerebrospinal fluid (CSF) within the
ventricles, or cavities, of the brain. CSF is a clear, colorless
fluid that is primarily produced by the choroid plexus and
surrounds the brain and spinal cord. CSF constantly circulates
through the ventricular system of the brain and is ultimately
absorbed into the bloodstream. CSF aids in the protection of the
brain and spinal cord. Because CSF keeps the brain and spinal cord
buoyant, it acts as a protective cushion or "shock absorber" to
prevent injuries to the central nervous system.
[0003] Hydrocephalus, which affects children and adults, arises
when the normal drainage of CSF in the brain is blocked in some
way. Such blockage can be caused by a number of factors, including,
for example, genetic predisposition, intraventricular or
intracranial hemorrhage, infections such as meningitis, head
trauma, or the like. Blockage of the flow of CSF consequently
creates an imbalance between the amount of CSF produced by the
choroid plexus and the rate at which CSF is absorbed into the
bloodstream, thereby increasing pressure on the brain, which causes
the ventricles to enlarge.
[0004] Hydrocephalus is most often treated by surgically inserting
a shunt system that diverts the flow of CSF from the ventricle to
another area of the body where the CSF can be absorbed as part of
the circulatory system. Shunt systems come in a variety of models,
and typically share similar functional components. These components
include a ventricular catheter which is introduced through a burr
hole in the skull and implanted in the patient's ventricle, a
drainage catheter that carries the CSF to its ultimate drainage
site, and optionally a flow-control mechanism, e.g., shunt valve,
that regulates the one-way flow of CSF from the ventricle to the
drainage site to maintain normal pressure within the ventricles.
The ventricular catheter typically contains multiple holes or
apertures positioned along the length of the ventricular catheter
to allow the CSF to enter into the shunt system, as shown in FIGS.
6 and 7.
[0005] Shunting is considered one of the basic neurosurgical
procedures, yet it has the highest complication rate. The most
common complication with shunting is obstruction of the system.
Although obstruction or clogging may occur at any point along the
shunt system, it most frequently occurs at the ventricular end of
the shunt system. While there are several ways that the ventricular
catheter may become blocked or clogged, obstruction is typically
caused by growth of tissue, such as the choroid plexus, around the
catheter and into the apertures, as shown in FIG. 7. The apertures
of the ventricular catheter can also be obstructed by debris,
bacteria, or coagulated blood.
[0006] Some of these problems can be treated by backflushing, which
is a process that uses the CSF present in the shunt system to
remove the obstructing matter. This process can be ineffective,
however, due to the small size of the apertures of the ventricular
catheter and due to the small amount of flushing liquid available
in the shunt system. Other shunt systems have been designed to
include a mechanism for flushing the shunt system. For example,
some shunt systems include a pumping device within the system which
causes fluid in the system to flow with considerable pressure and
velocity, thereby flushing the system. As with the process of
backflushing, using a built-in mechanism to flush the shunt system
can also fail to remove the obstruction due to factors such as the
size of the apertures and the degree and extent to which the
apertures have been clogged.
[0007] Occluded ventricular catheters can also be repaired by
cauterizing the catheter to remove blocking tissue, thereby
reopening existing apertures that have become occluded.
Alternatively, new apertures can be created in the catheter. These
repairs, however, may be incapable of removing obstructions from
the ventricular catheter depending on the location of the clogged
apertures. Additionally, the extent of tissue growth into and
around the catheter can also preclude the creation of additional
apertures, for example, in situations where the tissue growth
covers a substantial portion of the ventricular catheter. Another
disadvantage of creating new apertures to repair an occluded
ventricular catheter is that this method fails to prevent or reduce
the risk of repeated obstructions.
[0008] Because attempts at flushing or repairing a blocked
ventricular catheter are often futile and ineffective, occlusion is
more often treated by replacing the catheter. Although this can be
accomplished by removing the obstructed catheter from the
ventricle, the growth of the choroid plexus and other tissues
around the catheter and into the apertures can hinder removal and
replacement of the catheter. Care must be exercised to avoid damage
to the choroid plexus, which can cause severe injury to the
patient, such as, for example, hemorrhaging. Not only do these
procedures pose a significant risk of injury to the patient, they
can also be very costly, especially when shunt obstruction is a
recurring problem.
[0009] Accordingly, there exists a need for a shunt and a
ventricular catheter that minimizes or eliminates the risk of
blockage or obstruction of the catheter apertures, that increases
the ease of revision surgery if the catheter is removed and reduces
the need for repeated repair and/or replacement.
SUMMARY OF THE INVENTION
[0010] The present invention provides a shunt that includes a
housing having an inlet, an outlet and a flow control mechanism
disposed within the housing. A ventricular catheter is connected to
the inlet of the housing. The catheter has a longitudinal length, a
proximal end, a distal end, and an inner lumen extending
therethrough. The inner lumen of the catheter includes at least two
lumens at the distal end and has only one lumen at the proximal
end. The catheter has one aperture corresponding to each of the at
least two lumens located at the distal end of the catheter.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0011] FIG. 1 is a top perspective view of the shunt and
ventricular catheter according to the present invention;
[0012] FIG. 2 is a partial perspective view, with parts broken
away, showing the interior of the ventricular catheter according to
the present invention;
[0013] FIG. 3 is a cross-sectional view taken along lines 3-3 of
FIG. 2 and looking in the direction of the arrows;
[0014] FIG. 4 is a cross-sectional view taken along lines 4-4 of
FIG. 3 and looking in the direction of the arrows;
[0015] FIG. 4A is a cross-sectional view taken along lines 4A-4A of
FIG. 3 and looking in the direction of the arrows;
[0016] FIG. 5 is a cross-sectional view taken along lines 5-5 of
FIG. 3 and looking in the direction of the arrows;
[0017] FIG. 6 is a partial top view of a prior art ventricular
catheter;
[0018] FIG. 7 is cross-sectional view taken along lines 7-7 of FIG.
6 and looking in the direction of the arrows;
[0019] FIG. 8A is a partial top view of the ventricular catheter
according to the present invention; and
[0020] FIG. 8B is a partial top view of the ventricular catheter
according to the present invention.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
[0021] Referring now to FIGS. 1-5, 8A, 8B and 9 a shunt 10 and a
ventricular catheter 12 in accordance with the present invention is
illustrated.
[0022] As illustrated in FIG. 1, shunt 10 has a housing 14, which
has an inlet 16, an outlet 18 and a flow control mechanism disposed
therein. Ventricular catheter 12 is connected to inlet 16 of the
housing. Catheter 12 has a longitudinal length, a proximal end 20,
a distal end 22, and an inner lumen 24 extending therethrough.
Inner lumen 24 is a single lumen at proximal end 20 of the catheter
and is comprised of two or more lumens 24.sup.1, 24.sup.11,
24.sup.111, 24.sup.1111, etc. at the distal end 22 of catheter 12.
Catheter 12 is preferably made of silicone. In addition, catheter
12 can be impregnated with antimicrobial antibiotics, such as the
CODMAN.RTM. BACTISEAL.RTM. catheter, which is commercially sold by
Codman & Shurtleff, Inc. of Raynham, Mass.
[0023] Ventricular catheter 12 has only one aperture 26 at distal
end 22 of catheter 12 corresponding to each of the lumens 24.sup.1,
24.sup.111, 24.sup.1111, etc. There are preferably between 2 and
7lumens, with only three and four lumens being shown in the drawing
Figures for the sake of brevity. Of course, one skilled in the art
would readily know how to make the ventricular catheter of the
present invention with multiple lumens based on the present
disclosure. Each tapering slit 30 receives cerebrospinal fluid
(CSF) when in use. Each aperture 26 has an enlarged opening 28 at
the distal end and transitions from the enlarged opening to a
tapering slit 30 at the proximal end of the aperture. In some
examples of the present invention, for each aperture 26, a portion
32 between the enlarged opening 28 and the tapering slit 30 is a
slit 32 of constant thickness. Likewise, in other examples of the
present invention, for each aperture 26, there may be no portion 32
between the enlarged opening 28 and the tapering slit 30. In
addition, as illustrated in FIG. 9, for each aperture 26, a slit 42
of constant thickness can be disposed between the enlarged opening
28 and the proximal end of the aperture with no tapering slit being
utilized. The entire aperture, from the enlarged opening 28 to the
proximal end of tapering slit 30 is in fluid communication with its
respective lumen 24.sup.1, 24.sup.111, 24.sup.1111, etc. The
enlarged opening 28 of each aperture has a smooth concave inner
surface 34, similar to a spoon shape.
[0024] The use of multiple lumens 24.sup.1, 24.sup.111,
24.sup.1111, etc. in accordance with the present invention help
prevent complete occlusion of ventricular catheter 12. In the
present invention, ventricular catheter 12 can only be completely
occluded if all the lumens become blocked. In addition, because the
transition from multiple lumens to a single lumen 24 occurs from
about 0.5 to about 3.0 centimeters from the distal end of the
ventricular catheter, any ingrowth of choroid plexus or ependymal
tissue must extend beyond this junction to cause complete occlusion
and interconnection of tissue from multiple apertures, which is
unlikely to happen because of the length the tissue has to grow.
The only other way that the choroid plexus or ependymal tissue
would cause a complete occlusion is for the tissue to block each of
the multiple lumens 24 beyond the slit 30, or to occlude the entire
slit 30 and the aperture 26.
[0025] The slit lumen geometry is preferably tapered or purposely
shaped to provide resistance to fluid flow through the slit that
corresponds to the size of the pathway provided by the slit. The
size of the slit opening distributes the pressure gradient over a
larger distance and surface area than conventional ventricular
catheters. Diffusing the pressure gradient diminishes the
attractive fluid forces and diminishes areas of high fluid flow,
thereby lessens the propensity for tissue ingrowth.
[0026] Referring now to FIGS. 8A and 8B of the present invention,
tissue ingrowth 36 is illustrated. As can be seen, tissue ingrowth
into aperture 26 will not interconnect with tissue ingrowth from
another lumen. Thus, should the ventricular catheter 12 need to be
removed, catheter 12 will be pulled back out and tissue ingrowth 36
can be removed from the lumen at the wider end of the taper or at
the enlarged opening 28, as illustrated in FIG. 8B. In contrast, in
the prior art, tissue ingrowth 36 can be rather difficult to
remover from the ventricular catheter should the ventricular
catheter 12 need to be removed, as discussed above.
[0027] Referring now to FIGS. 2 and 3, ventricular catheter 12, has
a blunt distal end 38 to permit the catheter to be introduced into
the brain without damaging brain tissue. In addition, an inner
concave surface 40 is sized to receive a stylet for use in
introducing the catheter.
[0028] It will be understood that the foregoing is only
illustrative of the principles of the invention, and that various
modifications can be made by those skilled in the art without
departing from the scope and spirit of the invention. All
references cited herein are expressly incorporated by reference in
their entirety.
* * * * *