U.S. patent application number 13/427232 was filed with the patent office on 2013-09-26 for fluid management catheter and methods of using same.
This patent application is currently assigned to CODMAN & SHURTLEFF, INC.. The applicant listed for this patent is ALAN J. DEXTRADEUR, DANIEL McCUSKER. Invention is credited to ALAN J. DEXTRADEUR, DANIEL McCUSKER.
Application Number | 20130253266 13/427232 |
Document ID | / |
Family ID | 47915568 |
Filed Date | 2013-09-26 |
United States Patent
Application |
20130253266 |
Kind Code |
A1 |
DEXTRADEUR; ALAN J. ; et
al. |
September 26, 2013 |
FLUID MANAGEMENT CATHETER AND METHODS OF USING SAME
Abstract
A catheter and method for managing fluid in a patient, the
catheter having an elongated shaft with a distal end and a proximal
end. The shaft defines at least one lumen extending substantially
therethrough, the shaft further defining a plurality of drainage
holes along a distal portion of the shaft, with the drainage holes
in fluid communication with the lumen. The catheter further has a
substantially transparent tip portion attached to the distal end of
the shaft with an outer distal leading surface that is
substantially rounded to assist insertion through tissue.
Inventors: |
DEXTRADEUR; ALAN J.;
(FRANKLIN, MA) ; McCUSKER; DANIEL; (Bridgewater,
MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DEXTRADEUR; ALAN J.
McCUSKER; DANIEL |
FRANKLIN
Bridgewater |
MA
MA |
US
US |
|
|
Assignee: |
CODMAN & SHURTLEFF,
INC.
RAYNHAM
MA
|
Family ID: |
47915568 |
Appl. No.: |
13/427232 |
Filed: |
March 22, 2012 |
Current U.S.
Class: |
600/104 ; 604/43;
604/540 |
Current CPC
Class: |
A61N 5/0603 20130101;
A61M 25/0069 20130101; A61M 2027/004 20130101; A61M 2210/0693
20130101; A61B 1/313 20130101; A61B 2018/00446 20130101; A61M
27/006 20130101; A61M 25/0068 20130101; A61B 2018/00982 20130101;
A61N 2005/0612 20130101; A61B 2018/1807 20130101; A61B 2018/2261
20130101; A61M 25/007 20130101; A61B 1/00165 20130101; A61B 1/015
20130101; A61B 18/24 20130101; A61N 5/0601 20130101; A61B 2218/002
20130101; A61M 27/00 20130101; A61B 2018/2005 20130101 |
Class at
Publication: |
600/104 ;
604/540; 604/43 |
International
Class: |
A61M 27/00 20060101
A61M027/00; A61B 1/00 20060101 A61B001/00; A61M 3/02 20060101
A61M003/02 |
Claims
1. A fluid management catheter, comprising: an elongated shaft
having a distal end and a proximal end, the shaft defining at least
one lumen extending substantially therethrough, the shaft further
defining a plurality of drainage holes along a distal portion of
the shaft, the drainage holes being in fluid communication with the
lumen; and a substantially transparent tip portion attached to the
distal end of the shaft and having an outer distal leading surface
that is substantially rounded to assist insertion through
tissue.
2. The catheter of claim 1 wherein the tip portion defines at least
one opening in fluid communication with one of (i) the shaft lumen
and (ii) an irrigation lumen.
3. The catheter of claim 2 wherein the at least one opening is
substantially arcuate.
4. The catheter of claim 1 further including at least one
substantially transparent insert disposed along the distal portion
of the shaft.
5. The catheter of claim 4 wherein the shaft carries an optical
conduit in optical communication with the at least one insert.
6. A fluid management catheter suitable for implantation into a
ventricle in a brain of a patient, comprising: an elongated shaft
having a distal end and a proximal end, the shaft defining at least
one lumen extending substantially therethrough, the shaft further
defining a plurality of drainage holes along a distal portion of
the shaft, the drainage holes being in fluid communication with the
lumen; and a substantially transparent tip portion attached to the
distal end of the shaft and having an outer distal leading surface
that is substantially rounded to assist blunt dissection through
tissue.
7. The catheter of claim 6 wherein the tip portion defines at least
one opening in fluid communication with the shaft lumen and the
exterior of the catheter.
8. The catheter of claim 7 wherein the at least one opening is
substantially arcuate.
9. The catheter of claim 6 further including an irrigation lumen,
the tip portion defining at least one opening in fluid
communication with the irrigation lumen to direct irrigation fluid
along at least a portion of the outer distal leading surface of the
distal tip.
10. The catheter of claim 9 wherein the at least one opening is
substantially arcuate.
11. The catheter of claim 6 further including a plurality of
substantially transparent inserts disposed along the distal portion
of the shaft.
12. The catheter of claim 11 wherein the shaft carries an optical
conduit in optical communication with the inserts.
13. The catheter of claim 1 wherein the tip portion includes a wide
angle lens.
14. The catheter of claim 1 wherein the tip portion includes a
fisheye-type lens.
15. A method for managing fluid within a brain of a patient,
comprising: selecting a catheter having an elongated shaft with a
distal end and a proximal end, the shaft defining at least one
lumen extending substantially therethrough, the shaft further
defining a plurality of drainage holes along a distal portion of
the shaft, the drainage holes being in fluid communication with the
lumen, the catheter further having a substantially transparent tip
portion attached to the distal end of the shaft with an outer
distal leading surface that is substantially rounded to assist
insertion through tissue; inserting the catheter through tissue in
the brain to enter a selected ventricle; and visualizing through
the tip portion of the catheter while positioning the tip portion
within the selected ventricle.
16. The method of claim 15 wherein the tip portion defines at least
one opening in fluid communication with one of (i) the shaft lumen
and (ii) an irrigation lumen separate from the shaft lumen.
17. The method of claim 16 further including delivering fluid into
the brain through at least the opening in the tip portion.
18. The method of claim 15 further including placing a distal end
of a fiber-optic shaft into the shaft lumen of the catheter and
against the tip portion to view, indirectly and substantially
continuously through the tip portion, tissue within the selected
ventricle.
19. The method of claim 18 further including removing the
fiber-optic shaft from the catheter after the tip portion has been
positioned at a desired location.
20. The method of claim 18 wherein inserting the catheter includes
applying force to the fiber-optic shaft to assist insertion of the
distal tip through tissue.
21. The method of claim 15 further including delivering therapeutic
optical radiation through at least the tip portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a device and methods for managing
bodily fluids in a patient and more particularly to an implantable
catheter having an optically useful tip.
[0003] 2. Description of the Related Art
[0004] There are a number of conditions in patients for which it is
desirable to add or withdraw fluid. Some fluid management
conditions involve the mammalian brain. Within the cranium, gray
and white matter is suspended in cerebrospinal fluid and nourished
by blood delivered through cerebral arteries. The gray matter has
closely spaced cell bodies of neurons, such as in the cerebral
cortex, and the underlying white matter contains densely packed
axons that transmit signals to other neurons. Human brain tissue
has different densities and comprises approximately eighty percent
of the intracranial content, with blood and cerebrospinal fluid
each normally comprising approximately ten percent.
[0005] Cerebrospinal fluid is produced in several connected
chambers known as ventricles and typically is renewed four to five
times per day. Cerebrospinal fluid in a healthy human flows slowly
and continuously through the ventricles, propelled by pulsations of
the cerebral arteries. The fluid flows around the brain tissues and
the spinal column, and then through small openings into the
arachnoid membrane, which is the middle layer of the meninges
surrounding the brain parenchyma and ventricles, where the fluid is
finally reabsorbed into the bloodstream.
[0006] Under normal conditions, bodily mechanisms compensate for a
change in fluid volume within the cranium through tissue resilience
and by adjusting the total volume of blood and cerebrospinal fluid
so that a small increase in fluid volume does not increase
intracranial pressure. Similarly, a healthy brain compensates for
an increase in intracranial pressure to minimize a corresponding
increase in intracranial volume. This volume- and
pressure-relationship can be explained in terms of cerebral
compliance, which term is intended to include herein the terms
elastance and intracranial compliance.
[0007] The brain is compliant as long as a person's auto-regulatory
mechanism can compensate for any change in volume. As soon as the
brain's auto-regulation or compensatory mechanisms fail, blood and
cerebrospinal fluid cannot be displaced, and the brain can no
longer adapt to any increase in fluid volume. A reduction in
cerebral compliance eventually will lead to an undesired increase
in intracranial pressure, also known as hydrocephalus. As more
fluid volume is added, a threshold is reached beyond which small
increases in volume lead to dramatic and unhealthy increases in
intracranial pressure.
[0008] A typical device to treat fluid conditions such as
hydrocephalus is a ventricular catheter disclosed by Watson et al.
in U.S. Pat. No. 5,738,666. In one embodiment, ventricular catheter
22 has a slit 60 in a distal tip 58. A terminal end 40 of a rigid
introducer cannula 34 is inserted through the slit 60 during final
placement of the ventricular catheter within a selected ventricle.
A Tuohy-Borst adaptor 32 is secured to the proximal end of the
introducer cannula 34. During set-up, a fiber-optic shaft 66 of an
endoscope is advanced through the adaptor 32 and the cannula 34
until a fiber-optic terminal end 28 emerges past ventricular
catheter terminal end 58 and aligns with introducer terminal end
40. Fiber-optic shaft 66 is then interlocked relative to introducer
cannula 34. The aligned tips of the fiber-optic shaft 66 and the
introducer cannula are then retracted proximally within catheter 22
during advancement through tissue until a selected ventricle is
reached.
[0009] In other words, visualization does not occur during
navigation of the Watson et al. catheter through the brain tissue
and at least some of a selected ventricle. The doctor or other user
is "blind" until the fiber-optic shaft is advanced through the slit
in the ventricular catheter. Complications which may arise during
placement of a ventricular catheter include injury to vascular
structures such as the choroid plexus, injury to neurological
structures, and improper positioning of the distal tip of the
catheter.
[0010] There are a number of brain disorders that arise from
neurotoxins or other pathogenic substances which can accumulate in
cerebrospinal fluid. For example, it has long been recognized that
aggregation of the protein amyloid-beta, which can be found in
cerebrospinal fluid, contributes to the degenerative condition
known as Alzheimer's disease. Microscopic damage to brain tissue
leads to atrophy and a general decline in brain function known as
dementia.
[0011] Delivery of a substance or certain wavelengths of optical
radiation may be beneficial for some medical conditions.
Introducing one or more compounds to treat Alzheimer's disease is
described, for example, by DiMauro et al. in U.S. Patent
Publication No. 2010/0286585. Introduction of red light through the
cribriform plate portion of a nasal cavity to treat Alzheimer's
disease is disclosed in U.S. Pat. No. 7,351,253 by DiMauro et al.
It is therefore desirable to have a simpler and more accurate
device and technique for managing bodily fluids, especially
cerebrospinal fluid.
SUMMARY OF THE INVENTION
[0012] An object of the present invention is to enable continuous
visualization during insertion of a fluid management catheter in a
patient, particularly within a fluid-filled region.
[0013] Another object of the present invention is to minimize
exposure of the distal tip of an endoscope to tissue during
placement of the catheter without impairing visualization.
[0014] This invention features a catheter having an elongated shaft
with a distal end and a proximal end. The shaft defines at least
one lumen extending substantially therethrough, the shaft further
defining a plurality of drainage holes along a distal portion of
the shaft, with the drainage holes in fluid communication with the
lumen. The catheter further has a substantially transparent tip
portion attached to the distal end of the shaft with an outer
distal leading surface that is substantially rounded to assist
insertion through tissue.
[0015] In a preferred embodiment, the tip portion defines at least
one opening in fluid communication with (i) the shaft lumen, (ii)
an irrigation lumen, or (iii) both the shaft lumen and the
irrigation lumen. The irrigation lumen is defined by the shaft
separately from the shaft lumen in some embodiments and, in other
embodiments, is defined by independent structure such as a
fiber-optic shaft or other optical conduit. In one embodiment, the
opening is substantially arcuate.
[0016] In some embodiments, at least one substantially transparent
insert is disposed along the distal portion of the shaft, and the
shaft carries an optical conduit in optical communication with the
at least one insert. The optical conduit is fixed in one embodiment
and is removable in another embodiment. In one embodiment, the tip
portion includes a wide angle lens such as a fisheye-type lens.
[0017] This invention may also be expressed as a method for
managing fluid within a brain of a patient by selecting a catheter
having an elongated shaft with a distal end and a proximal end, the
shaft defining at least one lumen extending substantially
therethrough, the shaft further defining a plurality of drainage
holes along a distal portion of the shaft, and the drainage holes
being in fluid communication with the lumen. The catheter further
has a substantially transparent tip portion attached to the distal
end of the shaft with an outer distal leading surface that is
substantially rounded to assist insertion through tissue. The
method further includes inserting the catheter through brain tissue
to enter a selected ventricle, and visualizing through the tip
portion of the catheter while positioning the tip portion within
the selected ventricle.
[0018] In some embodiments, the tip portion defines at least one
opening in fluid communication with one of the shaft lumen and an
irrigation lumen defined by the shaft. The method further includes
delivering fluid into the brain through at least the opening in the
tip portion.
[0019] In other embodiments, the method includes placing a distal
end of a fiber-optic shaft into the lumen of the catheter and
against the tip portion to view, indirectly and substantially
continuously through the tip portion, tissue within the selected
ventricle. In certain embodiments, the method further includes
removing the fiber-optic shaft from the catheter after the tip
portion has been positioned at a desired location. In some
embodiments, force is applied to the fiber-optic shaft to assist
insertion of the distal tip through tissue. In yet other
embodiments, therapeutic optical radiation is delivered through at
least the tip portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In what follows, preferred embodiments of the invention are
explained in more detail with reference to the drawings, in
which:
[0021] FIG. 1 is a partial cross-sectional coronal view of a
patient showing a ventricular catheter according to the present
invention being implanted within the brain according to one
embodiment of the present invention;
[0022] FIG. 2 is an enlarged side view of the distal portion of a
ventricular catheter according to another embodiment of the present
invention within a ventricle;
[0023] FIG. 3 is an enlarged side view of the distal portion of
another embodiment of a ventricular catheter according to the
present invention within a ventricle;
[0024] FIG. 3A is an enlarged end view of the distal tip of the
catheter of FIG. 3; and
[0025] FIG. 4 is a flow chart of one implantation technique
according to the present invention.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0026] This invention may be accomplished by a catheter having an
elongated shaft with a distal end and a proximal end. The shaft
defines at least one lumen extending substantially therethrough,
the shaft further defining a plurality of drainage holes along a
distal portion of the shaft, with the drainage holes in fluid
communication with the lumen. The catheter further has a
substantially transparent tip portion attached to the distal end of
the shaft with an outer distal leading surface that is
substantially rounded to assist insertion through tissue,
preferably by blunt dissection to minimize trauma to the brain
tissue.
[0027] The head of a patient P is illustrated in coronal
cross-section in FIG. 1 with a ventricular catheter 10 according to
the present invention inserted through incision I in soft tissue
and skin SN and through burr hole BH at an upper region of skull
SL. A distal portion 12 of catheter 10 is shown positioned within a
lateral ventricle V after passing through cerebral cortex CC, white
matter WM and corpus callosum CM along surgical tract ST formed by
the insertion of catheter 10.
[0028] A fiber-optic shaft 20 is positioned within a lumen 16
extending through shaft 14 of catheter 10 to establish a
visualization assembly 22. Housing 30 enables force to be applied
by a surgeon or other user to fiber-optic shaft 20 as described in
more detail below. Cable 32 optically connects fiber-optic shaft 20
with an optics module during insertion of catheter 10. In some
constructions, cable 32 also delivers illuminating light during
insertion and, in other constructions, delivers therapeutic optical
radiation after insertion of catheter 10.
[0029] In this construction, fiber-optic shaft 20 also defines an
irrigation lumen as described in more detail below. One suitable
fiber-optic shaft with irrigation lumen is the NeuroPEN endoscope
available from Medtronic PS Medical. Handle 30 has a luer-lock port
34 to which a syringe 40, with plunger 42, can be mated to deliver
injection fluid IF such as a saline solution for irrigation or a
mixture including one or more compounds for therapeutic
purposes.
[0030] FIG. 2 illustrates one construction of a ventricular
catheter 10a according to the present invention with a distal
portion 12a positioned within a ventricle V and having
substantially optically transparent inserts 50, 52, 54, 56, 58, 60,
62 and 64 as well as fluid management openings 51, 53, 55, 57, 59
and 61. One advantage of the illustrated configuration of
alternating inserts and openings is that optical radiation can be
directed over a large volume while still enabling withdrawal or
delivery of fluid over a significant amount of the distal portion
12a.
[0031] In this construction, the inserts 50, 52 . . . 64 and distal
tip 18a are formed of a medical grade PMMA (polymethyl
methacrylate) such as FDA-approved Polycast PMMA, preferably with a
low roughness value. To further minimize growth of cells or
accumulation of substances on the PMMA substrates, the PMMA
preferably is exposed to a gas plasma of a fluorinated carbon or
otherwise treated in a manner similar to ophthalmic lenses. In some
constructions, heparin surface modifications reduce adherent cells
and debris. The catheter shaft 10 is formed of a silicone elastomer
in one construction and is formed of other flexible, medical-grade
polymers in other constructions. One or more antimicrobial agents
may be coated onto the shaft 10 or incorporated into the shaft
material during manufacture.
[0032] The pattern of projected optical radiation through distal
tip 18a and the inserts 50, 52 . . . 64 is pre-determined by the
curvature of the inner and outer surfaces of those elements. A
plano-convex or bi-convex lens will converge or focus optical
radiation, especially if the radiation is substantially collimated
such as produced by a laser. A plano-concave or bi-concave lens
will diverge or spread imaging and illumination over a larger area.
Optical radiation is shown diverging through the inserts and the
distal tip in FIG. 2 into the cerebral spinal fluid within
ventricle V. In some constructions, the distal tip is configured to
magnify images viewed through it, or provide a wide angle view such
as a fisheye-type expanded view. A wide angle lens such as a
fisheye-type lens is desirable to increase the field of view for a
user while minimizing distortion. Different types of lenses can be
utilized according to the present invention for inserts 50 . . . 64
and distal tip 18a such as lenses disclosed for ophthalmic implants
by Grendahl and Isaacson et al. in U.S. Pat. Nos. 4,759,762 and
5,152,788, respectively, and for catheters by Farr et al. in
5,782,825. A rounded, substantially bullet-shaped outer surface is
preferred for the distal tip to facilitate blunt dissection of
tissue as the catheter is advanced through brain tissue. A distal
tip according to the present invention provides an effective
viewing lens larger than the inner diameter of the catheter and,
therefore, larger than is possible for any endoscope insertable
through the catheter.
[0033] The inserts and distal tip are secured to the shaft of the
catheter with a biocompatible adhesive, an ultrasonic welding
technique, or other suitable procedure. In some constructions, the
distal tip has a proximally extending lead or post which mates with
the inner diameter of the shaft 10a. In some constructions with at
least one substantially transparent insert disposed along the
distal portion of the shaft, an optical conduit is carried by the
shaft in optical communication with the at least one insert. The
optical conduit is fixed in one construction and is removable in
another construction.
[0034] Another construction of a ventricular catheter 10b is shown
in FIGS. 3 and 3A. A distal portion 12b defines at least rows 70
and 72 of openings through which fluid enters into a central shaft
lumen 16b and is withdrawn proximally. A distal tip 18b defines
arcuate openings 74 and 76 through which irrigation fluid or
therapeutic fluid can be directed. Having at least one opening in
the distal tip 18b also enables cerebrospinal fluid or other bodily
fluid to be selectively withdrawn from the distal-most region of
catheter 10b, together with or independently of optical radiation
being directed through tip 18b, according to physician preference.
In this construction, distal portion 12b carries a radiographic
marker 78 formed of a radiopaque material such as tantalum.
Alternatively, a radiopaque material may be incorporated into the
transparent material of one or more inserts shown in FIG. 2 and/or
the transparent material of distal tips 10a, 10b.
[0035] One procedure according to the present invention for fluid
management within a brain of a patient is represented by the flow
chart of FIG. 4. A shaft of an endoscopic device is inserted, step
80, into a lumen of a ventricular catheter according to the present
invention to establish a visualization assembly. This assembly is
established inside an operating room in one procedure and is
established outside of the operating room in other procedures. The
visualization assembly, referred to as the catheter in step 82, is
advanced through brain tissue until a selected ventricle is
reached. Step 84, shown in phantom, represents optional irrigation
of at least a portion of the outer surface of the distal tip, such
as for the ventricular catheter illustrated in FIGS. 3 and 3A.
Irrigating through the distal tip flushes debris from the line of
sight of the endoscope. Irrigation can also be utilized to maintain
a positive pressure within the catheter to reduce ingress of
cellular debris.
[0036] It is a realization of the present invention that enabling
viewing through an optically transparent tip of a ventricular
catheter when a selected ventricle is reached is likely to minimize
damage to sensitive tissue during placement of the ventricular
catheter, step 86. The viewing may be considered as indirect
visualization through the optically transparent distal tip, which
protects the endoscope shaft from direct contact with brain tissue
during placement of the catheter. As noted above, complications
which may arise during conventional placement of a ventricular
catheter include injury to vascular structures such as the choroid
plexus, injury to neurological structures, and improper positioning
of the distal tip of the catheter.
[0037] Advancing the catheter through brain tissue, step 82, and
positioning the catheter in a ventricle, step 86, preferably
utilizes the endoscope shaft as a stylet. The distal tip of the
catheter acts as a stop, that is, prevents axial translation of the
endoscope shaft relative to the catheter, so that force applied to
the endoscope shaft is directly transmitted to the distal tip to
advance the catheter, preferably via blunt dissection of brain
tissue.
[0038] Once the distal portion of the catheter is in a desired
position the endoscope shaft is removed, step 88, and fluid is
added and/or removed, step 90, according to surgeon preference and
desired modality of treatment. In some techniques, therapeutic
optical radiation is delivered through at least the distal tip.
Utilizing a catheter having longitudinal inserts such as catheter
10a, FIG. 2, enables therapeutic optical radiation to be delivered
through inserts 50, . . . 64 over a large volume of fluid.
[0039] Thus, while there have been shown, described, and pointed
out fundamental novel features of the invention as applied to
preferred embodiments thereof, it will be understood that various
omissions, substitutions, and changes in the form and details of
the devices illustrated, and in their operation, may be made by
those skilled in the art without departing from the spirit and
scope of the invention. For example, it is expressly intended that
all combinations of those elements and/or steps that perform
substantially the same function, in substantially the same way, to
achieve the same results be within the scope of the invention.
Substitutions of elements from one described embodiment to another
are also fully intended and contemplated. It is also to be
understood that the drawings are not necessarily drawn to scale,
but that they are merely conceptual in nature. It is the intention,
therefore, to be limited only as indicated by the scope of the
claims appended hereto.
[0040] Every issued patent, pending patent application,
publication, journal article, book or any other reference cited
herein is each incorporated by reference in their entirety.
* * * * *