U.S. patent application number 11/368491 was filed with the patent office on 2006-09-14 for tissue removal apparatus.
This patent application is currently assigned to Baylis Medical Company Inc.. Invention is credited to Laura Conquergood, Mark Leung, Caitlyn Paget.
Application Number | 20060206128 11/368491 |
Document ID | / |
Family ID | 36952920 |
Filed Date | 2006-09-14 |
United States Patent
Application |
20060206128 |
Kind Code |
A1 |
Conquergood; Laura ; et
al. |
September 14, 2006 |
Tissue removal apparatus
Abstract
A method and apparatus are disclosed for removal of materials
from a body. The apparatus comprises an elongate member defining a
lumen and comprising a distal end defining an aperture and a
proximal end. The apparatus further comprises a shaft having at
least one outwardly extending projection for conveying tissue
through the lumen of the elongate member. The shaft is rotatably
disposed within the lumen. The shaft has a proximal end and a
distal end, and the distal end of the shaft is recessed proximally
relative to the aperture of the elongate member when the shaft is
fully disposed within the lumen of the elongate member.
Inventors: |
Conquergood; Laura;
(Mississauga, CA) ; Leung; Mark; (Toronto, CA)
; Paget; Caitlyn; (Toronto, CA) |
Correspondence
Address: |
DIMOCK STRATTON LLP
20 QUEEN STREET WEST SUITE 3202, BOX 102
TORONTO
ON
M5H 3R3
CA
|
Assignee: |
Baylis Medical Company Inc.
Saint Laurent
CA
|
Family ID: |
36952920 |
Appl. No.: |
11/368491 |
Filed: |
March 7, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11128342 |
May 13, 2005 |
|
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11368491 |
Mar 7, 2006 |
|
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60594109 |
Mar 11, 2005 |
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Current U.S.
Class: |
606/180 |
Current CPC
Class: |
A61B 2017/00261
20130101; A61B 17/320758 20130101; A61B 17/32002 20130101; A61B
17/320016 20130101; A61B 2018/0044 20130101; A61B 90/06 20160201;
A61B 2090/032 20160201; A61B 2090/065 20160201; A61B 18/148
20130101; A61B 2017/320775 20130101; A61B 2017/00685 20130101 |
Class at
Publication: |
606/180 |
International
Class: |
A61B 17/32 20060101
A61B017/32 |
Claims
1. An apparatus for removal of materials from a body, the apparatus
comprising: an elongate member defining a lumen and comprising a
distal end defining an aperture, said elongate member further
comprising a proximal end; and a tissue removal member comprising a
shaft having at least one outwardly extending projection for
conveying tissue through said lumen, said shaft being rotatably
disposed within said lumen, said shaft having a proximal end and a
distal end, the distal end of the shaft being recessed proximally
relative to said aperture when said shaft is fully disposed within
said lumen.
2. The apparatus of claim 1, wherein said elongate member is
bent.
3. The apparatus of claim 1, wherein said aperture has a radial
dimension and a longitudinal dimension.
4. The apparatus of claim 1 further comprising a motorized source
of rotational energy operatively connected to the shaft.
5. The apparatus of claim 4, further comprising a handpiece
operatively connected to said shaft.
6. The apparatus of claim 5, further comprising a motorized source
of rotational energy operatively connected to said tissue removal
member, wherein said handpiece comprises means for engaging and
disengaging said motorized source of rotational energy.
7. The apparatus of claim 1, wherein said shaft includes a
plurality of outwardly extending projections.
8. The apparatus of claim 7, wherein said outwardly extending
projections form at least one helix.
9. The apparatus of claim 1, wherein said shaft is an auger.
10. The apparatus of claim 1, further comprising a receptacle
operatively connected to the elongate member for receiving the
tissue removed from the body, said elongate member defining at
least one opening for transferring material from said elongate
member to said receptacle.
11. The apparatus of claim 10, wherein said receptacle is
detachable from said elongate member.
12. The apparatus of claim 10, wherein said receptacle is at least
partially pervious to light.
13. The apparatus of claim 10, wherein said receptacle is
transparent.
14. The apparatus of claim 1, wherein said elongate member is at
least partially pervious to light.
15. The apparatus of claim 1, wherein said shaft comprises a
substantially lubricious coating.
16. The apparatus of claim 1, wherein said aperture defined by the
distal end of the elongate member is defined in a plane that is
substantially perpendicular to the longitudinal axis of said
elongate member.
17. The apparatus of claim 1, further comprising an annular
component disposed around said shaft at a proximal portion
thereof.
18. A kit comprising: a motor; a handpiece structured to house said
motor; an elongate member defining a lumen and comprising a
proximal end and an open distal end, said proximal end structured
to be operatively connected to said handpiece; an auger sized to be
rotatably disposed within said lumen, the auger comprising a
proximal end and a distal end, the auger proximal end operable to
be operatively connected to said motor; a control disposed on said
handpiece for engaging and disengaging said motor; and a
receptacle; wherein the distal end of the auger is recessed
proximally from the distal end of the elongate member when the
auger is fully disposed within the elongate member.
19. The kit of claim 18, further comprising mean for sealing the
receptacle.
20. The kit of claim 19, wherein said means for sealing the
receptacle comprises a cap.
Description
TECHNICAL FIELD
[0001] This application claims priority from and is a
continuation-in-part of co-pending U.S. patent application Ser. No.
11/128,342, filed May 13, 2005. In addition, this application
claims the benefit of: U.S. provisional application No. 60/594,109
filed Mar. 11, 2005. The aforementioned applications are all herein
incorporated by reference.
[0002] The invention relates to devices for removal of material
from a patient's body. More particularly, the invention relates to
such devices that are minimally invasive.
BACKGROUND OF THE ART
[0003] A number of medical conditions exist that may require a
sample of tissue to be removed from a patient's body. U.S. Pat. No.
6,673,023 B2 (granted on Jan. 6, 2004), as well as U.S. patent
application Ser. No. 10/093,765 (filed on Mar. 8, 2002), Ser. No.
10/093,774 (filed on Mar. 8, 2002), Ser. No. 10/667,768 (filed on
Sept. 22, 2003), and Ser. No. 11/134,569 (filed on May 20, 2005),
all to Pflueger, describe a device and methods for removal of
tissue from a body. The device generally includes a handpiece
coupled to a tissue removal member having a cannula and a rotable
element with helical threading. In all the embodiments shown, the
rotable element extends beyond the distal tip of the cannula, and
the apparatus is designed to draw tissue into the cannula upon
rotation of the rotable element. The rotable element, however, may
pose the threat of damage to body tissue that it contacts, in that
it may penetrate, screw in to, or puncture such tissue. Thus there
exists a need for minimally invasive devices for removing tissue
from a patient's body that overcome some or all of the deficiencies
of the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] In order that the invention may be readily understood,
embodiments of the invention are illustrated by way of examples in
the accompanying drawings, in which:
[0005] FIG. 1A is a perspective view of one embodiment of the
device of the invention.
[0006] FIG. 1B is a side-view of one embodiment of the device of
the invention.
[0007] FIG. 1C is a top-view of one embodiment of the device of the
invention.
[0008] FIGS. 2A-D are perspective views of several embodiments of
the distal portion of the elongate member.
[0009] FIG. 3 is a sectional view of the distal portion of one
embodiment of the apparatus.
[0010] FIGS. 4A-E are perspective views of several embodiments of
the slits of the apparatus.
[0011] FIG. 5 is a sectional view of one embodiment of the
apparatus.
[0012] FIG. 6 is a sectional view of one embodiment of one portion
of the apparatus.
[0013] FIG. 7 is a cutaway view of the distal portion of one
embodiment of the distal portion of the apparatus.
[0014] FIGS. 8A-8L are illustrations of one embodiment of an
application of the method of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] With specific reference now to the drawings in detail, it is
stressed that the particulars shown are by way of example and for
purposes of illustrative discussion of certain embodiments of the
present invention only, and are presented in the cause of providing
what is believed to be the most useful and readily understood
description of the principles and conceptual aspects of the
invention. In this regard, no attempt is made to show structural
details of the invention in more detail than is necessary for a
fundamental understanding of the invention, the description taken
with the drawings making apparent to those skilled in the art how
the several forms of the invention may be embodied in practice.
[0016] Before explaining at least one embodiment of the invention
in detail, it is to be understood that the invention is not limited
in its application to the details of construction and the
arrangement of the components set forth in the following
description or illustrated in the drawings. The invention is
capable of other embodiments or of being practiced or carried out
in various ways. Also, it is to be understood that the phraseology
and terminology employed herein is for the purpose of description
and should not be regarded as limiting.
Definitions
[0017] As used herein, the term "at", for example when referring to
something being located "at" a specific location, is intended to
include any one or more of: proximate, on, near, adjacent to or
within the specific location.
[0018] As used herein, the terms "distal" and "proximal" are
defined with respect to the user. In other words, the term "distal"
refers to the part or portion further away from the user, while the
term "proximal" refers to the part or portion closer to the
user.
[0019] As used herein, the "posterior portion" of the nucleus
pulposus refers to the approximately half of the nucleus pulposus
that is closest to the dorsal side of the body, and the "anterior
portion" of the nucleus pulposus refers to the approximately half
of the nucleus pulposus that is closest to the ventral side of the
body.
[0020] As used herein, the term "shaft" refers to an elongate
element having either a closed or open distal end.
[0021] As used herein, the term "bent" refers to any deviation from
a longitudinal axis.
[0022] As used herein, the term "slot" refers to an outcutting,
slit, gap, or hole and is not limited in size or shape.
[0023] As used herein, the term "obturator" refers to any item that
substantially fills or blocks a lumen.
[0024] As used herein, the term "cannula" is defined as an elongate
device defining a lumen.
[0025] As used herein, the term "coring" refers to advancing an
elongate member defining a lumen and having an open distal end into
a tissue, wherein the advancement results in the incorporation or
gathering of at least a portion of the tissue into the lumen of the
elongate member.
[0026] As used herein, the phrase "operatively connected" is
intended to mean "coupled or connected, either directly or
indirectly, such that the connected structures are operable to
perform a desired function".
[0027] As used herein, the term "conveyance" refers to facilitation
of movement of a material from one location to another.
[0028] Finally, as used herein, the term "fully disposed" refers to
a first member being substantially fully received within a second
member such that, under normal use, it is not intended to be
inserted into the other member any further.
Device
[0029] In one broad aspect, the present invention comprises an
apparatus for removal of materials from the body of a patient. In
one specific embodiment of the method, the apparatus is used for
removal of nucleus pulposus tissue from an intervertebral disc. The
apparatus may generally comprise a tissue removal member housed at
least partially within an elongate member defining a lumen, for
example a sheath. The tissue removal member may be any device that
functions to convey tissue from the distal end of the elongate
member to a portion exterior to the patient's body. In one
embodiment, the tissue removal member is a shaft with at least one
projection extending outwardly from the shaft. The shaft may have a
plurality of projections extending outwardly therefrom. In one
embodiment, the tissue removal member is operatively connected to a
motor or other source of rotational energy which provides the
motion required to remove the tissue.
[0030] In the general embodiment shown in FIG. 1, the apparatus
comprises an elongate member 102, a handpiece 140, and a receptacle
138 for collection or visualization of tissue.
[0031] In one embodiment of the present invention, elongate member
102 comprises proximal portion 104 ending in open proximal end 106,
and distal portion 108 ending in open distal end 110. In other
embodiments, described in more detail below, proximal end 106 may
be closed and proximal portion 104 may define one or more apertures
in a lateral wall thereof. Open distal end 110 defines aperture
112. In one specific embodiment, the cross-sectional shape of
elongate member 102 is substantially circular, however alternate
embodiments are possible, wherein the shape may be ovoid, square,
or rectangular, and elongate member 102 is not limited in this
regard. The plane in which aperture 112 is defined may be
substantially perpendicular to the longitudinal axis of elongate
member 102; however distal end 110 of elongate member 102 may be
beveled or otherwise oriented, in which case the plane of aperture
112 would not necessarily be perpendicular to the longitudinal axis
of the shaft.
[0032] In one specific embodiment, elongate member 102 is sized to
be percutaneously directed to an interior tissue of the body. The
length of elongate member 102 is generally between about 15.0 and
about 25.0 cm, more specifically between about 17.0 and about 19.0
cm; however it may be otherwise sized to reach any target tissue
within the body. The diameter of elongate member 102 is generally
between about 0.5 and about 5.0 mm, more specifically between about
1.0 and about 2.0 mm, however it may be otherwise sized to fit
within the space defined by the target tissue.
[0033] In one embodiment, elongate member 102 may be bent or
curved, as shown in FIGS. 2A-2D. This may allow for easier access
to a target site. The bend or curve may be applied by the user
prior to or during the procedure, or may be applied during
manufacture. Many angles are possible depending on the nature of
the target tissue. For example, if the target tissue is the nucleus
pulposus of an intervertebral disc, the curve may be at such an
angle that the posterior portion of the nucleus pulposus may be
reached with the device while allowing for an approach that reduces
risk of damage to the spinal canal. In this example, the angle of
curvature would generally be between about 1.0 and about 5.00.
Furthermore, the curve or bend may be located at various points
along the length of the elongate member. Distal end 110 of elongate
member 102 may additionally comprise a variety of geometries such
as blunt, sharp, beveled, crown-shaped, fishhook shaped, or any
other shape that will not interfere with the proper functioning of
apparatus 100.
[0034] Elongate member 102 may be manufactured from a number of
different materials. These include, but are not limited to,
stainless steels, shape-memory materials such as nickel titanium
alloys, polyesters, polyethylenes, polyurethanes, polyimides,
nylons, copolymers thereof, and medical grade plastics. In one
specific embodiment, elongate member 102 is made from a clear,
transparent or translucent plastic or other material. This
embodiment may allow the user to visualize the contents of elongate
member 102 to ensure that it is operating properly.
[0035] In one embodiment, elongate member 102 is structured to
define at least one slot in distal portion 108. The at least one
slot 114 may function to allow more tissue to enter elongate member
102, and may allow for ease of movement through the target tissue,
while still maintaining the separation of the non-target tissues
from tissue removal member 116. Referring now to FIG. 4, slot(s)
114 may extend proximally from distal end 110 of elongate member
102. Slot(s) 114 may extend to a point on elongate member 102 that
is substantially coplanar with distal end 136 of shaft 128 when
shaft 128 is fully inserted into sheath 102. As used herein, the
term 'substantially coplanar may include any deviation from
coplanarity that would not interfere with the functioning of the
apparatus. Therefore, slot(s) 114 may extend to a point that is
either proximal or distal to distal end 136 of shaft 128. In one
embodiment, slot(s) 114 may be between about 0.5 mm and about 3 mm
in length. Referring now to FIGS. 4A-4E, slot(s) 114 may be defined
in a variety of shapes including rectangular, square, triangular,
or any other shape that would not interfere with the proper
functioning of apparatus 100. When a plurality of slots is
included, the slots may be circumferentially arranged in any manner
that will not interfere with the proper functioning apparatus 100.
For example, elongate member 102 may include 2 slots that are
diametrically opposite each other, or substantially adjacent to
each other. In another example, elongate member 102 may include 3
slots that are equidistant from each other, or that are all
arranged on one hemisphere of the distal end of the elongate
member. In other embodiments, different arrangements and shapes of
slots may be included. Furthermore, when a plurality of slots is
included, the shape, positioning, or size of each of the slots need
not be identical.
[0036] Slot(s) 114 may be created in a number of ways. For example,
a Dremel or other rotary tool may be used to cut or sand slot 114
into elongate member 102. Alternatively, sheath 102 may be
manufactured with slots 114 included.
[0037] With respect to FIGS. 3, 5, and 7, apparatus 100 comprises
tissue removal member 116, which is structured to be disposed
within elongate member 102. Tissue removal member 116 comprises a
proximal portion ending in a proximal end, and distal portion 122
ending in distal end 124. In one embodiment, tissue removal member
116 may be coaxial with elongate member 102; however tissue removal
member 116 may be otherwise aligned. In one embodiment, the length
of tissue removal member 116 is such that the proximal portion of
tissue removal member 116 extends proximally beyond proximal end
106 of elongate member 102; however proximal ends of elongate
member 102 and tissue removal member 116 may be flush or otherwise
aligned. In a specific embodiment, distal end 124 of tissue removal
member 116 is recessed proximally from the distal end of elongate
member 102. This structure allows for distal portion 122 of tissue
removal member 116 to be substantially shrouded within elongate
member 102. This arrangement may protect surrounding tissues from
being damaged by contact with tissue removal member 116. The
distance by which tissue removal member 116 is recessed from distal
end 110 of elongate member 102 is generally between about 0.5 and
about 4.0 mm, more specifically between about 0.5 and about 2.0 mm;
however, in this embodiment, the distance may be any amount such
that tissue removal member 116 does not contact tissue until after
the tissue has already entered elongate member 102. Further details
regarding the recession of tissue removal member 116 are discussed
hereinbelow.
[0038] In one embodiment, tissue removal member 116 comprises a
shaft 128 having outwardly extending projections 126. In a more
specific embodiment, the outwardly extending projections may
comprise a helical flighting or helical element disposed at least
partially around shaft 128. This arrangement may functionally form
an auger, wherein the term auger refers to a device for moving or
displacing material or liquid by means of a rotating helical
flighting. However, any other structure that functions as an auger
may be used, such as a screw or a drill bit. In one embodiment,
outwardly extending projections 126 extend from distal portion 136
of shaft 128 and may end in proximal portion 130 of shaft 128. In a
specific embodiment, outwardly extending projections 126 may end at
a point located within receptacle 138, as described hereinbelow.
Tissue removal member 116 is not limited to having one continuous
helical projection; it may comprise a plurality of discrete
projections that are either continuous or discontinuous over the
length of the shaft, as shown in FIG. 3B. The geometry of the
outwardly extending projections may vary in the thickness of the
projections, the distance between projections, or in any other way
that does not affect the functionality of the device. In addition,
the diameter of projections 126 may be constant or may vary. In the
case of a constant diameter, projections 126 may be sized such that
tissue removal member 116 fits exactly within sheath 102, or
projections 126 may be sized such that the diameter of tissue
removal member 116 is smaller than the inner diameter of sheath
102. Furthermore, shaft 128 is not limited to one continuous shaft,
and may comprise a plurality of shaft segments as shown in FIG.
3C.
[0039] Distal end 136 of shaft 128 of tissue removal member 116 may
have many shapes, and the invention is not limited in this regard.
For example, distal end 136 may be blunt, sharp, rounded, or
otherwise shaped. Furthermore, distal portion 134 may be straight,
bent, curved, beveled, or otherwise fashioned.
[0040] In one specific embodiment, outwardly extending projections
126 may be welded to shaft 128. In another embodiment, outwardly
extending projections 126 may be integrally formed with shaft 128.
Shaft 128 can be manufactured from a number of different materials.
These include, but are not limited to, stainless steels,
shape-memory materials such as nickel titanium alloys, polyesters,
polyethylenes, polyurethanes, polyimides, nylons, copolymers
thereof, and medical grade plastics. Furthermore, any combination
of the above materials may be used to optimize the physical
properties of apparatus 100. For example, a plastic coating
disposed on a metal core may optimize flexibility and strength.
Outwardly extending projections 126 may be manufactured from a
number of different materials, including but not limited to
stainless steels, nitinol, and various plastics and polymers.
Outwardly extending projections 126 may be attached to shaft 128 by
welding, for example laser welding, or by any other suitable method
of joining two such components, such as crimping, soldering, or the
use of adhesives. Alternatively, as mentioned above, projections
126 may be integrally formed with shaft 128 during the
manufacturing process. In other words, shaft 128 and projections
126 may be manufactured or machined as one single device, such as
the case of a screw or a drill-bit.
[0041] In one specific embodiment, shaft 128 may be at least
partially coated with a substantially lubricious material. Such a
material would be one that facilitates movement of shaft 128
through elongate member 102. In addition, the inner surface of
elongate member 102 may be coated with such a material. Suitable
lubricious materials include, but are not limited to,
polytetrafluoroethylene, parylene, or tungstenite.
[0042] Tissue removal member 116 may generally be between about 6
inches and about 18 inches in length, more specifically between
about 10.0 inches and about 13.5 inches. The diameter of shaft 128
may generally be between about 0.012 inches and about 0.042 inches,
more specifically between about 0.016 inches and about 0.028
inches. The width of outwardly extending projections 126 may
generally be between about 0.003 inches and about 0.025 inches,
more specifically between about 0.005 inches and about 0.010
inches.
[0043] As previously mentioned, apparatus 100 may comprise a
receptacle for housing and/or viewing the tissue that is removed
from the body. Herein, such a receptacle may be referred to as a
collection chamber. Collection chamber 138 may be manufactured in a
variety of sizes depending on the application. In one embodiment,
collection chamber 138 may be structured to be coaxial with
elongate member 102 and tissue removal member 116. In such an
embodiment, collection chamber 138 may be located at, for example
adjacent to, proximal portion 104 of elongate member 102, wherein
proximal end 106 of elongate member 102 and distal portion 604 of
collection chamber 138 are operatively connected, for example
joined by a hub or lock 144. Hub or lock 144 may be a luer lock,
snap fit, or any other type of hub or joining mechanism that does
not interfere with the functioning of apparatus 100. In some
embodiments, proximal portion 104 of elongate member 102 may define
an opening such that tissue may exit therethrough and enter
collection chamber 138. In the embodiment shown in FIG. 6, the
opening is defined by proximal end 106 of elongate member 102. In
other embodiments, proximal portion 104 of elongate member 102 may
comprise one or more openings, for example in a lateral wall
thereof, for allowing tissue to pass therethrough into collection
chamber 138. It is to be noted that a means for tissue to exit
proximal portion 104 of elongate member 102 is not limited to
openings, and may include other means such as tubing, for example.
In such embodiments, collection chamber 138 may be structured to
receive tissue exiting proximal portion 104 of elongate member 102.
For example, distal portion 604 of collection chamber 138 may
define a hole or other opening that is aligned with open proximal
end 106 of elongate member 102, such that tissue may exit elongate
member 102 through open proximal end 106 and enter collection
chamber 138 through the hole defined by distal portion 604. In some
embodiments, tissue removal member 116 may extend through open
proximal end 106 of elongate member 102 into, and optionally
through, collection chamber 138, such that tissue may be deposited
or viewed therein. In this embodiment, hub or lock 144 may be
structured such that it does not interfere with the passage of
tissue from elongate member 102 into collection chamber 138, and
such that it allows tissue removal member 116 to extend from within
the lumen of elongate member 102, through open proximal end 106,
and into collection chamber 138. In a specific embodiment,
outwardly extending projections 126 of tissue removal member 116
may end at a position within collection chamber 138. This may help
to ensure that the tissue is deposited within collection chamber
138. Shaft 128 of tissue removal member 116 may further extend
through proximal portion 602 of collection chamber 138. In some
embodiments, collection chamber may be structured to be coupled to
handpiece 140. In these embodiments, proximal portion 602 of
collection chamber 138 may be joined to the distalmost portion of
handpiece 140 with hub or lock 146. Hub or lock 146 may be a luer
lock, snap fit, or any other hub or mechanism of joining that does
not interfere with the functioning of apparatus 100. In a further
embodiment, the collection chamber assembly may comprise a gasket
600 or any other device that would prevent tissue from exiting
proximal portion 602 of collection chamber 138. In the specific
embodiment shown in FIG. 6, distal portion 604 of collection
chamber 138 is operatively connected to elongate member 102,
proximal portion 602 of collection chamber 138 is operatively
connected to handpiece 140, and shaft 128 of tissue removal member
116 runs through collection chamber 138 and into handpiece 140. In
yet another embodiment, collection chamber 138 may be located
within handpiece 140.
[0044] In some embodiments, collection chamber 138 may be
structured to allow the user to visualize the contents of the
chamber. This may be accomplished by manufacturing collection
chamber 138 from a material that is clear, translucent,
transparent, or otherwise pervious to light. Such materials
include, but are not limited to, polycarbonate, polyvinylchloride,
and polypropylene. In another embodiment, collection chamber 138
may include means for measuring the amount of tissue that is
contained therein. The means may comprise, but are not limited to,
volume markings on the chamber, a movable indicator that may be
displaced by the tissue, or an electrically conductive marker that
may lead to auto-shutoff when a certain amount of tissue has been
removed. Furthermore, the moveable indicator may be structured such
that it can be preset by the user at a particular location, thus
facilitating the removal of a particular predetermined amount of
tissue.
[0045] In one embodiment, collection chamber 138 may be structured
to be detached from apparatus 100 while still maintaining the
tissue within collection chamber 138. This may be accomplished by
unscrewing or otherwise detaching collection chamber 138 from
handle 140 and elongate member 102, and sliding collection chamber
138 off of apparatus 100. Collection chamber 138 can then be capped
or otherwise closed or sealed with a snap-on cap, screw-cap, or any
other means of sealing or closing collection chamber 138. This
embodiment may allow for the tissue to be sent for further
analysis, for example to a pathology laboratory. Persons skilled in
the art will recognize that in some cases, tissue may stick to
shaft 128 of tissue removal member 116. In these cases, after
collection chamber 138 has been removed from apparatus 100, the
user may simply manually remove the tissue from apparatus 100, and
place it in a separate vial for collection. Alternatively, shaft
128 may be structured to be removed from handpiece 140 such that
tissue can be slid or pulled off the proximal end of shaft 128. In
one specific embodiment, a non-stick coating, such as Teflon, may
be included on the portion of the shaft that is within collection
chamber 138 to prevent tissue from sticking.
[0046] In another embodiment, collection chamber 138 may comprise a
removable collection vessel, sac, or pouch for ease of tissue
removal. This would be particularly useful in cases where
collection chamber 138 is multi-use and requires sterilization
[0047] As shown in FIG. 1, apparatus 100 may include handpiece 140.
The shape of handpiece 140 as shown in the embodiment of FIG. 1 may
allow for the user to grip and manipulate the apparatus in a number
of different ways. For example, the user may grasp handpiece 140
using an overhand "screwdriver" grip. This grip may be beneficial
for coarse movements such as insertion. In another example, the
user may employ a "pencil" grip. This grip may be beneficial for
fine or delicate movements, such as the navigation of apparatus 100
to the appropriate tissue. These techniques for gripping handpiece
140 are given as examples only, and are not meant to limit the
manner in which the user may grip the handpiece. In one embodiment,
a switch 142 may be recessed radially on handpiece 140, as shown in
FIG. 1, thereby helping to prevent apparatus 100 from being
inadvertently engaged. In another embodiment, handpiece 140 may
comprise a latch or guard to prevent switch 142 from being
inadvertently engaged.
[0048] Handpiece 140 may generally be sized to accommodate a number
of hand sizes. In a specific embodiment, handpiece 140 may be
structured to allow a user to easily grasp and manipulate the
apparatus.
[0049] The internal structure of one embodiment of handpiece 140 is
shown in FIG. 5. In such an embodiment, handpiece 140 may be
structured to house a battery 502, a motor 500, and electrical
connections 110 therebetween. In addition, switch 142 may be
located on handpiece 140, thereby rendering apparatus 100 self
contained and/or wireless. In this embodiment, handpiece 140 may
include an opening 504 for proximal end 130 of shaft 128 to enter
handpiece 140. Alternatively, in an embodiment where the shaft does
not enter handpiece 140, handpiece 140 may include an aperture for
the electrical connections joining the motor to the shaft to exit
therethrough. In one embodiment, the distalmost portion of
handpiece 140 may connected to proximal end 106 of elongate member
102. This connection may be temporary via a luer lock, a snap fit,
or any other type of anchoring, or may be permanent via the use of
adhesives. The connection may allow shaft 128 of the tissue removal
member 116 to extend therethrough. In these embodiments, handpiece
140 is preferably hollow and defines a lumen.
[0050] Handpiece 140 may be manufactured from a number of different
materials, including, but not limited to, molded plastics. In one
embodiment handpiece 140 may be formed from two pieces of molded
material that are sealed together with an adhesive or other
appropriate sealing technique. This would allow for motor 500,
battery 502, or any other desired items to be contained within the
handpiece.
[0051] In some embodiments, tissue removal member 116 may be
operatively connected to a source of motorized rotational energy,
for example a motor 500, to allow for rotation of tissue removal
member 116. Proximal end 118 of tissue removal member 116 may be
operatively connected to motor 500 by any one or more of a variety
of means for connecting, including but not limited to, flexible
tubing, a ball bearing joint, and a spring. The means for
connecting may be flexible such that tissue removal member 116 may
pivot with respect to motor 500. In one specific embodiment, motor
500 may be connected to battery 502 via standard electrical
connections 110; however motor 500 may use an alternative source of
power, such as a plug or cable for connecting directly to a power
outlet or other power supply. Switch 142 is under the control of
the user and allows current to flow from the source of power to
motor 500 when switch 142 in engaged. When switch 142 is engaged,
motor 500 may cause shaft 128 of tissue removal member 116 to
rotate, thereby rotating outwardly extending projections 126 and
conveying tissue from the distal portion 122 of tissue removal
member 116 to proximal portion 118. Motor 500 may be one of several
types of motors including, but not limited to, a direct current
motor, an alternating current motor, an air driven motor, or a
piezoelectric motor. Battery 502 may be disposable or rechargeable,
and may further be one of several types of battery including, but
not limited to, alkaline, nickel-cadmium, or lithium. Switch 142
may be one of several types of switches including, but not limited
to, a toggle, a button, a rocker, a single throw switch, or a
double throw switch. Furthermore, switch 142 may be configured such
that the user must hold the switch in the `on` position for the
motor to remain engaged.
[0052] In one embodiment, motor 500 may be configured to rotate
over a range of speeds rather than being limited to an `on` or
`off` position. In this embodiment, switch 142 may be configured to
permit adjustment of the speed by the user. The speed may generally
range from about 200 to about 15,000 rotations per minute (RPM).
Alternatively, the motor may include gears to adjust the torque or
speed of rotation of the shaft. In a further embodiment, motor 500
and switch 142 may be configured to allow tissue removal member 116
to rotate in an opposite direction. This may facilitate removal of
tissue from apparatus 100.
[0053] In embodiments comprising a bent sheath, as described
hereinabove, apparatus 100 may be modified to accommodate the bent
sheath. In one embodiment, helical projections 126 may be absent
over the portion of shaft 128 that is within the bend. In another
embodiment, segments of shaft 128 may be absent at regions within
the bend. In another embodiment, the diameters of the shaft or
helical projections or both the shaft and helical projections may
be reduced within the region of the bend with respect to the
diameter of the sheath. In another embodiment, the thickness of
helical projections 126 may be variable over the length of shaft
128. In another embodiment, the finish on the interior surface of
sheath 102 may be modified to reduce any friction that may occur
between sheath 102 and tissue removal member 116. In another
embodiment, the speed of rotation of the shaft may be slowed, by
using a geared motor, for example, in order to reduce any friction
that may occur between sheath 102 and tissue removal member
116.
[0054] In some embodiments, apparatus 100 may comprise an
introducer apparatus that will aid in introducing elongate member
102 into the target tissue. The introducer apparatus may include a
hollow elongate introducer or cannula and an obturator. Cannula 700
may be substantially stiff or rigid, such that it may assist in
piercing skin or other body tissues, or such that it may provide
support for apparatus 100. Obturator 801 may be structured to
cooperatively engage with cannula 700. In other words, obturator
801 may be sized to fit within the lumen of cannula 700 and may
comprise means for securing obturator 801 to cannula 700. In one
embodiment, the outer diameter of obturator 801 may be such that
when obturator 801 is fully disposed within cannula 700, obturator
801 sufficiently fills the lumen such that tissue is prevented from
entering the lumen when the introducer device is inserted into the
body. In some embodiments the distal tip of obturator 801 may be
sharp. In these embodiments, the distal tip of obturator 801 may be
conical, beveled, or more specifically, tri-beveled. The lengths of
obturator 801 and cannula 700 may vary depending on the
application. In one embodiment, cannula 700 will be sized such that
distal end 702 can reach the target tissue within the body while
the proximal end remains outside of the body. More specifically,
cannula 700 may be between about 5.5 and about 7.5 inches in
length, and obturator 801 may be between about 5.5 and about 7.5
inches in length. When the target tissue is an intervertebral disc,
cannula 700 may be about 6.4 inches in length, and obturator 801
may be about 6.6 inches in length. Obturator 801 may be slightly
longer than the cannula 700, so that distal end 810 of the
obturator may protrude from cannula 700 when fully disposed. The
lumen of cannula 700 may be sized to accommodate the diameter of
elongate member 102 and obturator 801, while remaining as small as
possible in order to limit the invasiveness of the procedure. In a
specific embodiment, the proximal regions of cannula 700 and
obturator 801 are structured to be locked together with hub or lock
808. In other words, the hub or lock comprises means for securing
cannula 700 to obturator 801.
[0055] In one embodiment, cannula 700 and obturator 801 may be made
from a stainless steel. In other embodiments, cannula 700,
obturator 801, or both may be made from other materials, such as
nickel-titanium alloys for example.
[0056] As previously mentioned, elongate member 102 may be inserted
through the lumen of cannula 700 in order to reach the target
tissue. In such an embodiment, elongate member 102 may comprise a
marking 812 on proximal portion 104, such that when distal end 110
of elongate member 102 and distal end 702 of cannula 700 are
aligned, the marking will be aligned with the proximal end of
cannula 700. The marking may take the form of a colored band, a
dot, or a notch, for example. The use of the marking is discussed
further hereinbelow.
[0057] In one embodiment, the length of cannula 700 may comprise
depth markings to aid the user in the placement of introducer
apparatus. Such markings would be spaced at specific distances
along the length of cannula 700, for example at every inch. Such
depth markings may be colored bands, notches, or dots for
example.
[0058] In one embodiment, cannula 700 includes a radiopaque marker
704 for visualizing the location of the cannula with respect to the
target tissue using x-ray fluoroscopic imaging. In such an
embodiment, radiopaque marker 704 may be located on the distal
portion of cannula 700. In another embodiment, a radiopaque marker
may be included on distal tip 810 of obturator 801. Examples of
such markers are disclosed in US patent application US2005000079318
(publication number US20050159797A1), and US2003000382836
(publication number US20040176759A1), both of which are
incorporated herein by reference.
[0059] In another embodiment, the distal portion of cannula 700 may
have one of a variety of configurations, including, but not limited
to, straight, bent, or beveled. In one specific embodiment, cannula
700 is straight, while distal portion 108 of elongate member 102 is
curved. In such an embodiment elongate member 102 may flexibly
conform to the shape of cannula 700 while disposed within the
introducer, but as it is passed through distal end 702 of cannula
100 it may reform to its curved shape.
[0060] In another embodiment, cannula 700 may include a port such
that a liquid may be delivered to the target tissue via cannula
700. Such a port may be located on the proximal region of the
cannula, and may comprise a hub for joining a supply of liquid
thereto.
[0061] As persons of skill in the art will recognize, the
introducer device described hereinabove may be used with other
devices that are structured to remove tissue from a nucleus
pulposus. The use of the introducer device is therefore not limited
to use with apparatus 100.
[0062] In a further embodiment, apparatus 100 may be operable to
deliver energy to a portion of the target tissue to further treat
the tissue. This energy may comprise radiofrequency electrical
energy, thermal energy, microwave energy, ultrasound energy, or
optical energy (e.g. laser energy). In a further embodiment,
apparatus 100 may further comprise a probe operable to deliver
energy, wherein probe refers to any element designed to deliver
energy to a tissue. In the case of a herniated intervertebral disc,
the application of radio frequency energy may cause the heating of
the tissue surrounding the probe. This may result in the shrinkage
of the nucleus pulposus tissue, which may act to further treat the
herniated disc. Examples of the use of energy to treat an
intervertebral disc are disclosed in U.S. Pat. No. 6,896,675 (filed
on 05 Mar. 2002) and US patent application US2005000128342
(publication number US20050234445A1), incorporated herein by
reference.
[0063] In another embodiment, apparatus 100 may comprise means for
measuring pressure within a patient's body. Examples of means for
measuring pressure are a pressure transducer, or a fluid filled
lumen for transmitting pressure. For example, in the case of an
intervertebral disc, there is an intrinsic pressure associated with
the nucleus pulposus tissue, and the pressure may be heightened in
the case of a diseased disc. The initial pressure, change in
pressure, or final pressure may be used to determine the amount of
tissue to be removed from the disc. In this embodiment, a pressure
sensor may be located in distal portion 108 of elongate member 102
or distal portion 134.of shaft 128, or alternatively, on a separate
instrument introduced into the target tissue. Furthermore,
electronic circuitry may be provided to cause an auto-shutoff of
apparatus 100 when a certain pressure has been reached.
[0064] In another embodiment, apparatus 100 may comprise means for
measuring the electrical impedance within a patient's body. This
feature may be useful, for example, in ensuring the proper
placement of apparatus 100 in the target tissue. In the case of an
intervertebral disc, the impedance within the annulus fibrosis of
an intervertebral disc may be different from that within the
nucleus pulposus of the disc. Thus, by measuring the impedance
between distal end 110 of elongate member 102 and a return
electrode, for example, it may be possible to determine whether
distal end 110 of elongate member 102 is in the annulus fibrosis or
nucleus pulposus. The impedance may be measured between a variety
of elements on the apparatus, for example between elongate member
102 and a return electrode, elongate member 102 and tissue removal
member 116, tissue removal member 116 and a return electrode,
obturator 801 and a grounding pad, or between any other desired
elements of the apparatus.
[0065] In another embodiment, apparatus 100 may comprise sensing
means for indicating whether tissue removal member 116 is
contacting or engaging tissue. Such means may include, but are not
limited to, an element for measuring the torque required to turn
motor 500, an element for measuring the forces exerted on elongate
member 102, or an element for measuring the current drawn by motor
500. The sensing means may be coupled to an indicator, such as a
light or an LED, for indicating to the user that the tissue has
been engaged.
[0066] In some embodiments, apparatus 100 may comprise means for
guiding distal end 110 of elongate member 102 in a desired
direction. For example, a pull-wire may be coupled to distal end
110 of elongate member 102, and may extend proximally to a point
located outside of the patient's body. By pulling on the pull-wire,
the user may cause distal end 110 of elongate member 102 to deflect
to a location that is closer to a target site.
[0067] In yet another embodiment, apparatus 100 may comprise an
observation system for visualizing the location or operation of
apparatus 100. Such a system may include, but is not limited to, an
ultrasonic or fiber-optic visualization apparatus disposed at
distal end 110 of elongate member 102 or tissue removal member 116.
Apparatus 100 may alternatively be configured for use with an
endoscope.
[0068] In another embodiment, apparatus 100 may comprise measuring
means for measuring the temperature at a particular position on the
apparatus. Such means may include a thermocouple, thermistor, or
resistance thermometer, for example. The temperature measurement
means may be located on distal end 110 of sheath 102, or distal end
136 of shaft 128 for example.
Method
[0069] In one broad aspect, the invention comprises methods for
removal of tissue from a body, wherein the methods are a
combination of coring and conveyance. The methods described herein
may be used to remove various types of materials from a patient's
body. Examples of such materials include, but are not limited to,
tissue of an intervertebral disc (for example, the nucleus
pulposus), tumor tissue (including, but not limited to, material
from breast, colon, stomach, or liver tumors), bone tissue (for
example, bone marrow), cyst material, adipose tissue, eye material,
cartilage, or atherosclerotic material.
[0070] While the general method for removing material may
substantially comprise similar steps (i.e. coring and conveyance of
material) regardless of the material being removed, the method of
introducing the apparatus into, or removing the apparatus from, the
target site, may vary depending on the material and/or target site.
For example, in the case of bone marrow an instrument for
penetrating bone, for example a hammer or a reamer, may be used to
access the portion of the bone where the marrow is located. In the
case of tumor material, extra caution may be required to ensure
that malignant cells do not track along the removal path of the
sheath of the tissue removal member so that tumor material is not
spread within the patient's body. In such an application, it may be
useful to cauterize the removal path of the sheath so that tissue
surrounding the path is destroyed. If a cannula is used to
introduce the device and remains in place during the procedure, as
discussed herein below, the cauterization step may not be
necessary, since the sheath of the tissue removal member doesn't
contact tissue as it's removed from the patient's body.
[0071] In one embodiment, the method of the present invention may
be practiced using apparatus 100, including tissue removal member
116 disposed within elongate member 102, as described hereinabove.
Alternatively, embodiments of the method of the present invention
may be practiced using any device that provides substantially
similar functionality with respect to the steps of coring and
conveying material. The steps of one embodiment of the method may
be described generally as follows: patient preparation, insertion
of the apparatus, activation of the apparatus, removal of the
apparatus and patient recovery. In addition, a user may desire to
analyze the tissue removed during the procedure. These steps will
presently be discussed in greater detail. In order to illustrate
the steps of this embodiment, reference will be made to a specific
application of this embodiment in removal of tissue from an
intervertebral disc (shown in FIGS. 8A-8L). It should be noted that
the steps described herein are not intended to be exclusive and
further steps may be performed in conjunction with embodiments of
the method of the present invention. In addition, some of the steps
described herein may be omitted and the invention is not limited in
this regard.
[0072] The step of patient preparation may comprise acquiring
patient data in order to prepare for the procedure as well as
positioning the patient appropriately. Pertinent data to be
acquired may include, but is not limited to, a medical history of
the patient, standard diagnostic test results (e.g. blood tests),
physical function and pain assessments and medical imaging
assessments of the patient's condition. In some embodiments, the
patient may be assessed using various imaging modalities such as
MRI, X-ray, CT scan or ultrasound prior to the tissue removal
procedure. These assessments may aid in determining the appropriate
location of the target site for tissue removal as well as the
amount of tissue to be removed. Prior to commencing the procedure,
the patient may be positioned in a prone position (depending on the
target site and the material being removed) and prepared using
standard pre-surgical techniques.
[0073] Once preparations for the procedure have been completed, the
apparatus may be inserted to the target site within the patient's
body. The location and angle of insertion may depend on the target
site and the specific material being removed. For example, in the
case of an intervertebral disc, the physician may insert the
apparatus into the foraminal and pedicle zones, superior to the
articular process, below the exiting spinal nerve, 20.degree. to
40.degree. from the sagittal plane, and roughly equidistant from
the superior and inferior endplates.
[0074] In some embodiments, the placement of distal end 110 of
elongate member 102 at the target site may be aided with the use of
an introducer apparatus. Referring now to the example illustrated
in FIGS. 8A and 8B, the introducer apparatus comprises an obturator
801 disposed within a cannula 700. The introducer apparatus is
advanced either percutaneously or in an open surgical procedure
into the body of the patient and towards the target site. When the
target site has been reached, obturator 801 is withdrawn proximally
from cannula 700, leaving a distal end 702 of cannula 700 at the
target site, for example as shown in FIGS. 8C and 8D. In the
illustrated embodiment, distal end 702 of cannula 700 is positioned
at the boundary between the annulus fibrosis 804 and the nucleus
pulposus 806 (i.e. the inner wall of the intervertebral disc).
[0075] In some embodiments, cannula 700 may comprise a radiopaque
marker 704 to aid in the placement of the introducer apparatus. In
such an embodiment, radiopaque marker 704 may be included at distal
end 702 of cannula 700. In alternate embodiments, radiopaque marker
704 may be located elsewhere on cannula 700. The placement of
cannula 700 may then be performed under fluoroscopy, such that the
visibility of distal end 702 of cannula 700 may be enhanced on the
fluoroscopic image by radiopaque marker 704. Alternatively or in
addition, various sensors may be used to assist in placing the
introducer apparatus appropriately. For example, in the case of an
intervertebral disc, an impedance measurement device may be
included on distal end 702 of cannula 700. As the annulus fibrosis
of an intervertebral disc may be of different electrical impedance
than the nucleus pulposus, the user may measure the electrical
impedance at distal end 702 of cannula 700 while inserting the
cannula. When the electrical impedance measurement indicates that
distal end 702 of cannula 700 has passed through the annulus
fibrosis and is within the nucleus pulposus, the user may stop the
insertion process. In further embodiments, a contrast solution may
be injected at the target site through the lumen of cannula 700 in
order to verify proper placement. For example, if the target site
is located within an intervertebral disc, the contrast solution,
when viewed under fluoroscopy, may allow a user to visualize the
boundary between the nucleus pulposus 806 and annulus fibrosis 804.
In addition, other substances may be injected through cannula 700
to the target site. The substance may be injected through an
injection port or hub coupled to cannula 700. For example, it may
be desirable to inject a fluid, including but not limited to an
antibiotic, an anesthetic or an analgesic substance, prior to
removing tissue from the target site.
[0076] Once cannula 700 is properly placed and any injections have
been completed, elongate member 102 may be inserted through the
lumen of cannula 700. For example, and referring now to FIGS. 8E
and 8F, elongate member 102 and tissue removal member 116 may be
advanced through the lumen of cannula 700, such that distal end 110
of elongate member 102 is located distal to distal end 702 of
cannula 700.
[0077] The device having been inserted to the target site, the
procedure may proceed by activating the tissue removal member in
order to remove tissue. This step of activating the device may
generally include engaging the motor to rotate the device and
advancing the device, including elongate member 102, through the
target site to core and convey a desired amount of material away
from the target site. More specifically, in one embodiment, the
user may advance distal end 110 of elongate member 102 into the
target site, engage motor 500, usually via switch 142, and while
motor 500 is engaged, advance apparatus 100 distally through the
target site. When apparatus 100 has been advanced a particular
distance, to be determined by the user depending on the size of the
target site and/or the amount of material to be removed, motor 500
may be disengaged, and elongate member 102 may be withdrawn
proximally through the target site. In the case of a curved
elongate member, as shown in FIG. 2, elongate member 102 may be
repositioned by rotating elongate member 102 about its longitudinal
axis, without requiring removal and re-insertion of elongate member
102 into the patient's body. Motor 500 may then be re-engaged, and
elongate member 102 may be advanced into a second region of the
target site. The activation step of the tissue removal procedure
may be repeated until the desired volume of tissue has been
removed. At this point, apparatus 100 may be removed from the body,
as discussed further below. It should be noted that, in some
embodiments, only one pass of elongate member 102 may be required
in order to remove the desired amount of tissue.
[0078] Without being restricted to a specific theory of operation,
a proposed mechanism of action of apparatus 100, in one embodiment
of the present invention, will be presently described. In
operation, tissue removal member 116 remains substantially static
or stationary with respect to the longitudinal axis of elongate
member 102. In other words, tissue removal member 116 does not move
`in and out` with respect to elongate member 102. Apparatus 100 is
advanced through the target site to core the material to be
removed. As apparatus 100 is advanced, material enters elongate
member 102 through aperture 112 and is forced proximally into
elongate member 102 by the advancement of apparatus 100. In other
words, material is substantially gathered into the lumen of
elongate member 102. As used herein, the term "substantially
gathered" may refer to a sample or portion of tissue that is still
connected with tissue outside of the lumen of elongate member 102,
or may alternatively refer to tissue that has been detached from
tissue outside of the lumen. At a certain location within elongate
member 102, the material contacts tissue removal member 116, which
functions to convey the material proximally from distal portion 108
of elongate member 102, to, for example, the exterior of the
patient's body. Tissue removal member 116 may function by a variety
of mechanisms. In one embodiment, tissue removal member 116 is
coupled to motor 500. Upon engagement of motor 500, tissue removal
member 116 rotates about its longitudinal axis. Outwardly extending
projections 126, described hereinabove, will engage the tissue
within elongate member 102, and convey the tissue toward proximal
end 120 of tissue removal member 116. In one specific embodiment,
proximal portion 118 of tissue removal member 116 is operatively
connected to collection chamber 138 as described hereinabove. In
this embodiment, the tissue may be conveyed from distal portion 108
of elongate member 102 and be deposited within chamber 138. As
described hereinabove, tissue removal member 116 is recessed from
distal tip 110 of elongate member 102; therefore the material does
not contact tissue removal member 116 until after the material has
entered the lumen of elongate member 102. This functions to protect
any non-target tissue from tissue removal member 116. For example,
in the case of an intervertebral disc, as shown in FIGS. 8I to 8L,
apparatus 100 is advanced through the soft tissue of nucleus
pulposus 806 to effect removal of the tissue as described above. As
apparatus 100 is advanced, it may eventually contact annulus
fibrosis 804, the integrity of which is essential to the health of
the disc. Due to the more rigid structure of the annulus fibrosis,
it may be prevented from being cored into elongate member 102, and
therefore, due to the fact that tissue removal member 116 is
recessed from distal tip 110, the annulus fibrosis will not contact
tissue removal member 116. Thus, the annulus fibrosis may be
protected from the high speed motion and projections of tissue
removal member 116.
[0079] In some embodiments, for example as shown in FIGS. 8G to 8L,
a clip 802, sliding depth marker, or other marking mechanism may be
used to indicate the location of distal end 110 of elongate member
102 within the patient's body. For example, in the case of an
intervertebral disc, the user may position distal end 110 of
elongate member 102 at the boundary of annulus fibrosis 804 and
nucleus pulposus 806, as described above with respect to the
positioning step. As shown in FIGS. 8G and 8H, the user may then
advance elongate member 102 distally through nucleus pulposus 806,
without activating tissue removal member 116, until distal end 110
of elongate member 102 contacts annulus fibrosis 804 on the
anterior side or portion of the disc. This point of contact may be
referred to the as the "anterior annulus inner wall" of the
intervertebral disc. The boundary between nucleus pulposus 806 and
annulus fibrosis 804 may be located by tactile sensation, as the
annulus fibrosis 804 is generally stiffer than the nucleus pulposus
806, or by using a contrast solution and performing the method
under fluoroscopy, as described hereinabove. The user may place
marker or clip 802 on the distalmost portion of elongate member 102
that is proximal to the proximal end of cannula 700, as shown in
FIG. 8G. Referring now to FIGS. 8I and 8J, the user may then
retract distal end 110 of elongate member 102 proximally to distal
end 702 of cannula 700. In one embodiment, proximal portion 104 of
elongate member 102 may comprise a marking 812 located such that
when the marking is aligned with the proximal end of cannula 700,
it indicates that the distal ends of cannula 700 and elongate
member 102 are aligned. Thus, when elongate member 102 is withdrawn
proximally through the disc, the user will know to stop retracting
elongate member 102 when marking 812 is aligned with the proximal
end of cannula 700. The user may then engage tissue removal member
116, and begin the coring and conveyance procedure. As shown in
FIGS. 8K and 8L, the user may stop advancing apparatus 100 through
the disc as marker or clip 802 approaches the proximal end of
cannula 700. The user may then withdraw apparatus 100 by realigning
the marking with the proximal end of cannula 700, and repeat the
coring and conveying step. The use of marker or clip 802 may help
to ensure that distal end 110 of elongate member 102 does not
contact annulus fibrosis 804. This may be especially advantageous
in the case of a severely damaged disc that may be severely
affected by damage to annulus fibrosis 804.
[0080] Termination of the procedure may be decided by a user, which
decision may be facilitated in one or more ways by the apparatus
being used. For example, the procedure may be terminated once a
sufficient amount of tissue has been removed. In the case of an
intervertebral disc, the amount of tissue to be removed may be up
to 3.0 grams, more specifically, between 0.05 and 1.5 grams.
Several methods may be used to determine when the appropriate
amount of tissue has been removed from the body. In one embodiment,
collection chamber 138 is at least partially pervious to light and
comprises volume markings for determining the amount of tissue held
within chamber 138. By visualizing the markings and/or the contents
of collection chamber 138, the user may decide when the desired
amount of tissue has been removed. Alternatively, collection
chamber 138 may comprise a sensing means for automatically
indicating when a desired amount of tissue has been removed. For
example, collection chamber 138 may be fitted with a sensor,
including but not limited to a pressure, optical or chemical
sensor, such that the sensor may provide an indication to the user
once a desired amount of tissue has been collected. The sensor may
be movable so that the user can adjust for the desired amount of
tissue for a given procedure. In one embodiment, tissue may be
collected and, once the amount of tissue collected is such that the
tissue contacts the sensor, the sensor may provide an indication,
for example, a visible or audible indication, that the desired
amount of tissue has been removed.
[0081] In another embodiment, a pressure monitoring device may be
coupled to apparatus 100. By monitoring the change in pressure at
the target site, the user may determine when the desired amount of
tissue has been removed. Alternatively, the pressure monitoring
device may be operable to provide an indication to the user when
the pressure has changed by a pre-determined amount. The indication
may take the form of, for example, a visible or audible indication
and may indicate to the user that the desired amount of tissue has
been removed. These embodiments are meant to be exemplary only, and
are not intended to limit the methods for determining when the
appropriate amount of tissue has been removed.
[0082] Once the procedure has been terminated, the tissue removal
member, as well as other components of the apparatus being used,
may be removed from the patient's body. The step of removing these
components may include, in some embodiments, removing elongate
member 102 from cannula 700, injecting a substance through cannula
700 and removing cannula 700 from the patient's body. For example,
it may be beneficial to inject a fluid, including but not limited
to an antibiotic fluid, into the target site to prevent the
possibility of infection.
[0083] In some embodiments, apparatus 100 may be maneuvered by the
user during, for example, the positioning, advancing, and removing
steps, by grasping handpiece 140 in one or more of a variety of
grips, as described hereinabove, and manipulating handpiece 140 to
control the position of elongate member 102 and tissue removal
member 116 at the target site.
[0084] The entire treatment procedure described herein may be
repeated at a different site, if necessary. Following completion of
all such procedures, the patient should be allowed to recover. In
addition, the user may collect material removed from the patient
during the procedure in order to allow for further analysis.
Collecting material from the tissue removal member may be
accomplished in several ways. For example, material may be removed
from tissue removal member 116 manually by scraping, tweezing or
otherwise grasping and removing the material. Alternatively, if
material has been collected within collection chamber 138, then
chamber 138 may be removed from apparatus 100, sealed and/or capped
and sent for analysis. In addition, as described further below,
motor 500 may be run at high speeds in order to convey material up
to collection chamber 138 prior to removal of chamber 138.
Furthermore, motor 500 may be operable to run in reverse, such that
material may be conveyed to distal portion 122 of tissue removal
member 116 which may allow for easier removal of material from
apparatus 100, for example.
[0085] In another embodiment, apparatus 100 may be used to
introduce material into a patient's body. For example, in the case
of an intervertebral disc, it may be desired to add artificial (for
example, synthetic) or natural (for example, xenobiotic) material
or tissue, such as collagen or cement, into the intervertebral
disc. In this embodiment, the material may be housed in receptacle
138, and motor 500 may be run in the reverse direction from that
used in the tissue removal process. In this embodiment, tissue
removal member 116 may be referred to as a motorized device. The
motorized device may engage the material housed in the receptacle,
and convey it distally through the lumen of elongate element 102
and deposit it in the body. In one specific embodiment, tissue may
be removed from the patient's body, and then material may be
introduced into the patient's body. In this embodiment, after the
tissue has been removed from the body as described above, apparatus
100 may be removed from the body and introducer apparatus, and the
receptacle housing the tissue may be replaced with a receptacle
housing the material to be introduced. Device 100 may then be
re-introduced into the patient's body, as described hereinabove,
and the motor may be run in reverse to convey the material into the
body. Device 100 may be advanced and withdrawn within the target
tissue in order to disperse the material. In another embodiment,
material may be introduced to the target site prior to removal of
tissue from the patient's body. In yet another embodiment, material
other than tissue, referred to herein as a "second material", such
as previously introduced cements or pharmaceutical compounds, may
be removed from the target site. This may be done either before or
after the introduction of material, and before or after a step of
removing tissue.
[0086] Some embodiments of the method aspect of the present
invention may comprise one or more further steps. For example, in
one embodiment, the method may comprise a step of delivering energy
to the target site before, during, or after removal of material. In
this embodiment, apparatus 100 may include a probe or other device
capable of delivering energy, as described hereinabove. The method
may thus include placement of the probe at the target site, and
activation of the probe to deliver energy. The user may advance or
otherwise move the probe within the tissue, or may keep the probe
stationary. Further details regarding such an embodiment may be
found in co-pending US Patent Application 20050234445 (published on
20 Oct. 2005), incorporated herein by reference.
[0087] In another embodiment, a second device may be separately
introduced into the patient's body. This device may be used to aid
in the collection of material. For example, as elongate member 102
and tissue removal member 116 are being operated at the target
site, the secondary device may be used to push tissue towards
elongate member 102.
[0088] In yet another embodiment, the method further comprises a
step of disposing of apparatus 100 after use. This may be
beneficial as single-use devices avoid several problems associated
with reusable devices, including those associated with bacterial
infections, viruses, and prions.
[0089] In some embodiments, the method may comprise one or more
steps of variably adjusting the speed (i.e. rotations per
minute--RPM) of motor 500. In such embodiments, motor 500 is
capable of rotating at various speeds, and the speed of motor 500
may be adjusted by the user. For example, the user may adjust the
speed by using a control element such as a dial, lever, knob, or
any other control element coupled to motor 500. In one such
embodiment, a user may adjust the motor to run at a high speed as
the user begins the tissue removal procedure, wherein a high speed
may be desirable to assist in rapidly removing material. Towards
the end of the procedure, however, the user may reduce the speed to
ensure that an excess of tissue is not removed. Furthermore, when
the procedure is completed and apparatus 100 has been removed from
the patient's body, the user may desire to rotate tissue removal
member 116 at a high speed to remove any tissue remaining in
elongate member 102 or on tissue removal member 116.
[0090] In another embodiment, the longitudinal motion of apparatus
100 may be automated. In such an embodiment, the advancement of
apparatus 100 into and through the target site would be automatic,
rather than as a result of force applied by the user.
[0091] As mentioned above, this embodiment of the method of the
present invention is not intended to be limited to use within an
intervertebral disc. Other tissues and/or materials may be removed
from a patient's body using the steps described above. Embodiments
of the present invention thus provide for a minimally invasive
apparatus that may be used to remove material, for example tissue
from a patient's body, while minimizing blood loss and trauma to
the patient.
[0092] The embodiments of the invention described above are
intended to be exemplary only. The scope of the invention is
therefore intended to be limited solely by the scope of the
appended claims.
[0093] It is appreciated that certain features of the invention,
which are, for clarity, described in the context of separate
embodiments, may also be provided in combination in a single
embodiment. Conversely, various features of the invention, which
are, for brevity, described in the context of a single embodiment,
may also be provided separately or in any suitable
sub-combination.
[0094] Although the invention has been described in conjunction
with specific embodiments thereof, it is evident that many
alternatives, modifications and variations will be apparent to
those skilled in the art. Accordingly, it is intended to embrace
all such alternatives, modifications and variations that fall
within the spirit and broad scope of the appended claims. All
publications, patents and patent applications mentioned in this
specification are herein incorporated in their entirety by
reference into the specification, to the same extent as if each
individual publication, patent or patent application was
specifically and individually indicated to be incorporated herein
by reference. In addition, citation or identification of any
reference in this application shall not be construed as an
admission that such reference is available as prior art to the
present invention.
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