U.S. patent application number 15/451583 was filed with the patent office on 2017-09-21 for introducer sheaths for endoscopes and related methods.
The applicant listed for this patent is CooperSurgical, Inc.. Invention is credited to Rosemary Michelle Garofalo, Thomas William Winegar.
Application Number | 20170265892 15/451583 |
Document ID | / |
Family ID | 59855483 |
Filed Date | 2017-09-21 |
United States Patent
Application |
20170265892 |
Kind Code |
A1 |
Winegar; Thomas William ; et
al. |
September 21, 2017 |
Introducer Sheaths for Endoscopes and Related Methods
Abstract
A sheath for inserting a cannula of an endoscope into a cavity
of a patient is described herein. The sheath comprises an
introducer, a support channel and a pull-tab. The introducer has an
open end being sized and shaped to accept a tip of the cannula and
a tip end adapted to be deflected in an outward direction by the
tip of the cannula passing into the introducer. The support channel
is adapted to receive a shaft of the cannula and guide the tip of
the cannula into the introducer; and the pull provides a finger
hold for a user to grasp the sheath. In some aspects, the
introducer includes a plurality of extending segments having a
normally closed position defining a conical exterior shape of the
introducer, with the plurality of tapered segments adapted to be
separated by the tip of the cannula passing through the
introducer.
Inventors: |
Winegar; Thomas William;
(Trumbull, CT) ; Garofalo; Rosemary Michelle;
(North Haven, CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CooperSurgical, Inc. |
Trumbull |
CT |
US |
|
|
Family ID: |
59855483 |
Appl. No.: |
15/451583 |
Filed: |
March 7, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62309121 |
Mar 16, 2016 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 25/0668 20130101;
A61B 17/3415 20130101; A61B 2017/345 20130101; A61M 2025/0687
20130101; A61B 17/3421 20130101; A61B 17/4241 20130101; A61B
1/00154 20130101; A61B 1/00085 20130101; A61B 1/303 20130101; A61B
17/3439 20130101; A61B 17/0218 20130101; A61B 2017/3454
20130101 |
International
Class: |
A61B 17/34 20060101
A61B017/34; A61B 1/00 20060101 A61B001/00; A61M 25/06 20060101
A61M025/06 |
Claims
1. A method of inserting a cannula of an endoscope into an internal
space of a patient, the method comprising: placing the cannula of
the endoscope within a support channel of a sheath, proximal to a
collapsed introducer at the insertion end of the sheath; advancing
the cannula and sheath through a cavity of a patient until the
collapsed introducer is inserted into an internal space of a
patient, the introducer at least partially dilating the internal
space; advancing the cannula along the support channel and through
the introducer; advancing the cannula within the support channel to
a desired distance within a cavity; and removing the cannula and
sheath from the patient.
2. The method of claim 1 wherein advancing the cannula through the
introducer expands the introducer and further dilates the internal
space.
3. The method of claim 1, further including, advancing an inner
sleeve of the sheath along the support channel and into the
introducer, the advancing of the inner sleeve expanding the
introducer and further dilating the internal space to enable the
advancing of the cannula through the introducer and into the
cavity.
4-10. (canceled)
11. A method of inserting a cannula of an endoscope into a cavity
of a patient, the method comprising: mounting a coiled sheath on a
distal end of the cannula of the endoscope; advancing the cannula
and coiled sheath through a cavity of the patient until a distal
end of the coiled sheath is inserted into an internal space of a
patient, the distal end of the coiled sheath partially dilating the
cavity; and removing the cannula and coiled sheath from the
patient.
12-14. (canceled)
15. A sheath for facilitating insertion of a cannula of an
endoscope into an internal space of a patient, the sheath
comprising: a support member adapted to receive a shaft of the
cannula; and an introducer positioned at a distal end of the
sheath, the introducer having a tip end and an open end at a distal
end of the introducer, the open end being sized and shaped to
accept a tip of the cannula, the tip end adapted to be deflected in
an outward direction.
16. The sheath of claim 15, wherein the introducer is biased in a
normally closed position.
17. The sheath of claim 15, wherein the introducer is biased in a
normally deflected position, and the tip end adapted to be
deflected inwardly prior to insertion of the sheath.
18. The sheath of claim 15, wherein the tip end is adapted to be
deflected in the outward direction by the tip of the cannula when
the tip of the cannula is inserted into the introducer.
19. The sheath of claim 15, wherein the support member comprises an
outer sleeve and an inner sleeve, the inner sleeve being in
slidably disposed in the outer sleeve, and wherein the tip end of
the introducer is adapted to be deflected in the outward direction
by the inner sleeve when a distal end of the inner sleeve is
inserted into the introducer.
20. The sheath of claim 15, further including a pull-tab extending
from the sheath, the pull-tab providing a finger hold for a user to
grasp the sheath.
21. The sheath of claim 15, wherein the support member defines a
support channel and includes a retention clasp adapted to
removeably secure the shaft of the cannula to the support
channel.
22. The sheath of claim 15, wherein the sheath is constructed from
a lubricious material or coated in a lubricious material.
23. The sheath of claim 15, wherein the introducer has a length
between 127 mm to 304.8 mm
24. The sheath of claim 15, wherein the introducer has an exterior
diameter of 2 mm to 30 mm.
25. The sheath of claim 15, wherein the introducer defines a
tapered or conical exterior surface.
26. The sheath of claim 15, wherein the introducer includes: a ring
that at least partially defines the open end; and a plurality of
segments extending from the ring to the tip end, the plurality of
tapered segments having a normally closed position defining a
conical exterior shape of the introducer, the plurality of tapered
segments adapted to be separated in a radial direction by the tip
of the cannula when the tip of the cannula is passes through the
introducer.
27. The sheath of claim 26, wherein each of the plurality of
tapered segments defines a triangular shape.
28. The sheath of claim 27, wherein each of the plurality of
tapered segments defines outside edges, the outsides edges of each
of the plurality of tapered segments positioned adjacent to the
outside edge of an adjacent tapered segment in the normally closed
position, and the outsides edges of each of the plurality of
tapered segments adapted to be separated by the tip of the cannula
when the tip of the cannula is passes through the introducer.
29. The sheath of claim 15, wherein the support member is a support
tube constructed from a coiled segment, the introducer includes:
the coiled segment extending from the support tube to the tip end
in an overlapping spiral, the coiled segment having a nominal
position defining a conical exterior shape of the introducer.
30. The sheath of claim 12, wherein the support member includes one
or more depth markings located on the support channel to identify
how far the cannula tip has been inserted into an internal space
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Patent
Application No. 62/309,121, filed on Mar. 16, 2016, the entire
contents of which is incorporated herein by reference.
FIELD
[0002] The present invention relates to a sheath for aiding
insertion of an endoscope, such as a hysteroscope, cystoscope,
ureteroscope, or laparoscope into a cavity, such as a uterus,
urinary bladder, ureters or abdominal cavity of a patient.
BACKGROUND
[0003] Hysteroscopy, or direct vision of the inside of the uterus,
has been shown to improve diagnostic accuracy. However, patients
often find the insertion and removal of the hysteroscopy apparatus
and, subsequently, the endoscopic apparatus into the patient's
uterine cavity uncomfortable. Typical hysteroscopy devices have a
distal tip end sized to facilitate insertion of the tip end through
the patient's cervix and into the uterus.
SUMMARY
[0004] Certain aspects of the invention relate to a sheath for
inserting a cannula of a hysteroscope through a cervix and into the
uterus of a patient. The present invention can also relate to
passing tools, such as an endoscope, laparoscope, or others into an
anatomical space. The present invention further relates to passing
tools when such passage may otherwise be difficult, such as into a
urinary bladder through a constriction such as structure or
sphincter. The sheath includes an introducer positioned at a distal
end of the sheath. The introducer has a tip end and an open end at
a distal end of the introducer. The open end is sized and shaped to
accept a tip of the cannula. The sheath includes a support channel
adapted to receive a shaft of the cannula and guide the tip of the
cannula into the introducer.
[0005] In some examples, the introducer is biased in a normally
closed position.
[0006] In some examples, the introducer is biased in a normally
deflected-open position, and the tip end adapted to be defected
inwardly prior to insertion of the sheath.
[0007] In some examples, the tip end is adapted to be deflected in
the outward direction by the tip of the cannula when the tip of the
cannula is inserted into the introducer.
[0008] In some examples, the support member includes an outer
sleeve and an inner sleeve, the inner sleeve being slidably
disposed in the outer sleeve, and the tip end of the introducer is
adapted to be deflected in the outward direction by the inner
sleeve when a distal end of the inner sleeve is inserted into the
introducer.
[0009] In some examples, a pull-tab extending from a proximal end
of the sheath provides a finger hold for a user to grasp the
sheath.
[0010] In some examples, the support channel includes a retention
clasp adapted to removeably secure the shaft of the cannula to the
support channel.
[0011] In some examples, the sheath is constructed from a
lubricious material or coated in a lubricious material.
[0012] In some examples, the sheath has an overall length of 127 mm
to 304.8 mm.
[0013] In some examples, the introducer has a length of 15 mm to 70
mm (e.g., about 30 mm). In some examples, introducer has an
exterior diameter of 2 mm to 30 mm (e.g., about 7.8 mm).
[0014] In some examples, the introducer defines a tapered or
conical exterior surface.
[0015] In some examples, the introducer includes a ring at the open
end, and a plurality of segments that extend from the ring to the
tip end. The plurality of tapered segments have a normally closed
position that define a conical exterior shape of the introducer,
and the plurality of tapered segments are adapted to be separated
in a radial direction by the tip of the cannula passing through the
introducer. When separated, the segments enable the cannula to pass
through the introducer.
[0016] In some examples, the introducer includes a ring at the open
end, and a plurality of segments that extend from the ring to the
tip end. The pluralities of tapered segments have a normally open
position. The segments forming a conical exterior shape of the
introducer are adapted to be closed by a user prior to insertion,
and the plurality of tapered segments are adapted to be separated
in a radial direction based on material properties. When separated,
the segments enable the cannula to pass through the introducer.
[0017] In some examples, the conical exterior shape is formed as a
single tapered segment. The radial expansion of the single tapered
segment is enabled by material property such as the elasticity or
an elastomer.
[0018] In some examples, each of the plurality of tapered segments
defines a triangular shape. In some examples, the plurality of
tapered segments together define a frustoconical shape.
[0019] In some examples, each of the plurality of tapered segments
defines outsides edges that are positioned adjacent to the outside
edge of an adjacent tapered segment in the normally closed
position, and the outsides edges of each of the plurality of
tapered segments are adapted to be separated by the tip of the
cannula passing through the introducer.
[0020] In some examples, the support member includes one or more
depth markings located on the support channel to identify how far
the cannula tip has been inserted into an internal space.
[0021] In some examples, the introducer includes a coiled segment
extending from the support tube to the tip end in an overlapping
spiral. The coiled segment has a normally tapered portion defining
a conical exterior shape of the introducer. In some examples, the
normal position derives a cylindrical exterior shape of the
introducer. The tip end of the introducer accepts the tip of the
cannula, and the coiled segment is adapted to at least partially
uncoil when the cannula shaft is translated toward the tip end. In
some examples, the uncoiling is caused directly by the translation
of the cannula which increases the diameter of the introducer at
the tip end. The increasing diameter enables the cannula to pass
through the introducer.
[0022] Another example is a method of inserting a cannula of a
hysteroscope through a cervix and into the uterus of a patient
using a sheath. The method includes placing a cannula within a
support channel of the sheath, proximal to a collapsed introducer
at the insertion end of the sheath, and advancing the cannula and
sheath through a vaginal canal until the collapsed introducer is
inserted into a cervical canal. The introducer at least partially
dilates the cervical canal. The cannula is advanced along the
support channel and through the introducer. The advancing cannula
expands the introducer and further dilates the cervical canal. The
cannula is advanced within the support channel to a desired
distance within the uterine cavity. The cannula and sheath are then
removed from the patient.
[0023] In some examples, advancing the cannula through the
introducer expands the introducer and further dilates the internal
space.
[0024] In some examples, the method further includes advancing an
inner sheath of the cannula along the support channel and into the
introducer, the advancing of the inner sheath expanding the
introducer and further dilating the internal space to enable the
advancing of the cannula though the introducer and into the
cavity.
[0025] In some examples, the method further includes, when the
distal end of cannula reaches a desired location, securing the
proximal end of cannula within the retention clasps of the
sheath.
[0026] In some examples, the method further includes advancing the
cannula and sheath until a pull-tab of the sheath contacts the
patient anatomy or vaginal opening/introitus of the patient.
[0027] In some examples, the method further includes orienting the
cannula in a desired position, guided by feedback from the
stiffness of the introducer.
[0028] In some examples, orienting the cannula in a desired
position is enabled by the introducer adding stiffness to the
cannula.
[0029] In some examples, the method further includes performing
diagnostic procedures in the uterine cavity with the distal end of
the cannula. In some examples, the diagnostic procedures include
acquiring images of the uterine cavity with the distal end of the
cannula.
[0030] In some examples, removing the cannula and sheath from the
patient includes removing the cannula and sheath together, at the
same time, from the cervix by pulling on the cannula and a pull-tab
on the proximal end of the sheath. In other examples, removal of
the cannula and the sheath together is enabled through a reversible
attachment between the cannula and sheath. In other examples, the
reversible attachment aligns the cannula in the sheath.
[0031] In some examples, removing the cannula and sheath from the
patient includes removing the sheath from the patient while the
cannula is still inserted within the cervix or uterine cavity.
[0032] Yet another example is a method of inserting a cannula of a
hysteroscope through the cervix and into the uterus of a patient
using a coiled sheath. The method comprises mounting the coiled
sheath on a distal end of the cannula, and advancing the cannula
and coiled sheath through a vaginal canal until a distal end of the
coiled sheath is inserted into a cervical canal. The distal end of
the coiled sheath partially dilates the cervical canal. The method
also includes advancing the cannula through the coiled sheath to a
desired distance within the uterine cavity. The advancing cannula
radially expands the coiled sheath and dilates the cervix.
[0033] In some examples, the method further includes orienting the
cannula in a desired position, which is enabled by the stiffness of
the coiled sheath.
[0034] In some examples, the method further includes removing the
cannula and coiled sheath from the patient includes unwinding the
coiled sheath from the cannula.
[0035] A sheath for inserting a cannula of a hysteroscope through a
cervix and into the uterus of a patient is described herein. The
sheath includes an introducer to be inserted into a cervix and
subsequently pass a tip of the cannula through the introducer,
whereby the cannula deflects a portion of the introducer in an
outward direction, to aid in the introduction of the tip of the
cannula to the uterus. In some aspects, the introducer includes a
plurality of extending segments having a normally closed position
defining a conical exterior shape of the introducer, with the
plurality of tapered segments adapted to be separated by the tip of
the cannula passing through the introducer.
[0036] Embodiments can include one or more of the following
advantages. In some embodiments, the sheath allows for easier
insertion of a hysteroscope through the cervix and into a uterus of
a patient. The sheath can allow for less painful hysteroscopy
procedures because the distal end of the sheath has a smaller
profile than the tip of the hysteroscope and, therefore, passes
into the cervix more easily than the hysteroscope alone would. In
certain embodiments, the sheath provides better
steerability/maneuverability of the hysteroscope during a
hysteroscopy procedure because, for example, the sheath can
increase the overall rigidity of the effective rigidity of the
hysteroscope. In some embodiments, the sheath can be removed from
the patient while leaving the hysteroscope in the uterus and/or
cervix. This can increase the comfort of the patient during the
hysteroscopy procedure.
[0037] Other aspects, features, and advantages will be apparent
from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF DRAWINGS
[0038] FIG. 1 is an illustration of a sheath with a splittable
introducer in a normally closed position.
[0039] FIG. 2 is an illustration of the sheath of FIG. 1 with the
splittable introducer in an open position.
[0040] FIGS. 3A-3D are illustrations of a cannula being inserted
into the sheath of FIG. 1.
[0041] FIG. 3E is an illustration of the sheath of FIG. 1 aiding
insertion of a cannula into the uterus of a patient.
[0042] FIG. 4A is an illustration of a sheath with a coiled
introducer in a normally coiled position.
[0043] FIG. 4B is an enlarged view of a distal end region of the
sheath of FIG. 4A.
[0044] FIGS. 5A-5C are illustrations of a cannula being inserted
into the sheath of FIG. 4A.
[0045] FIGS. 6A and 6B are illustrations of a sheath including a
perforated body.
[0046] FIG. 7A-7C are illustrations of a sheath including a hinged
body.
[0047] FIGS. 8A-8E are illustration of a sheath having a
dual-sleeve design.
DETAILED DESCRIPTION
[0048] The present disclosure presents methods and devices to allow
ease of insertion for a cannula or other tool to cross through a
tight orifice, such as a cervix, for a procedure such as
hysteroscopy. Additionally, some of the devices discussed herein
can be mated to a flexible cannula or some other tool to provide
the cannula or tool with increased stiffness, which can improve the
user's ability to pass the cannula or tool though a tight orifice
or can improve the user's ability to move the cannula or tool
laterally or rotationally during use.
[0049] The embodiments disclosed herein describe devices and
methods that provides easier access for a tool through a small,
undilated orifice. In some embodiments, the device is a single use,
disposable, generally cylindrical shape with a small distal
opening. The distal opening is of a size to fit through a small
orifice, such as the cervix of a nulliparous woman. A tool, such as
the diagnostic cannula of a hysteroscope, can be placed down the
inner diameter of the device. Both the inner diameter and outer
diameter of the device grow with the passage of the tool,
effectively dilating the orifice. In certain embodiments, the
device has a longitudinal slit or opening that allows removal of
the device without the removal of the tool. The tool can be left in
place within the cavity and the device can slide along the long
axis of the tool to remove the device from the patient. Then the
slit or opening enables the device to move away from the long axis
of the tool thereby removing the device from the tool.
[0050] Some examples of the present design improve insertion of
hysteroscopes and similar devices through a cervix and into the
uterus by providing a sheath to be inserted into the cervix, with a
tip end that expands and dilates the cervix as a cannula of a
hysteroscope passes through the sheath and past the cervix. Some
examples of the sheath include a distal tip end of a sheath shaft
split so that the distal tip end of the sheath collapses to make
the tip smaller for insertion. Once the sheath is in the uterus, an
instrument is able to be inserted down the cannula shaft and causes
the distal tip to widen for passage. In some embodiments, the
sheath passes into the uterus with the cannula. In some
embodiments, the sheath maintains the dilation of the cervix while
the cannula passes into the uterus. The instrument could also add
rigidity to the assembly for ease of maneuverability, and the
entire assembly is capable of rotation.
[0051] Some examples of the present design use an outer sheath that
is initially inserted into the cervix as a dilator for a
nulliparous cervix. The distal end of the sheath is small and the
distal end expands open as the cannula travels down the sheath. In
some instances, the sheath is made out of a stiffer material to aid
with steering of the cannula. In certain embodiments, the sheath
can be removed from the patient without removing the cannula. In
some instances, this is be accomplished through the use of a
longitudinal slit, a clamshell or hinged design that allows the
sheath to open, or by removing a section of the sheath as through
the use of a finger-grip.
[0052] FIG. 1 is an illustration of a sheath 100 with a splittable
introducer 110 in a normally closed position. As shown in FIG. 1
the splittable introducer 110 is provided at distal end of the
sheath 100. A support channel 120 extends from the introducer 110
to a proximal end of the sheath 100. The support channel 120
includes a curved channel surface 122 formed into a rigid support
member 121 and a pull-tab 140 secured to the rigid support member
121. The support channel 120 also includes a retention clasp 130
extending above the curved channel surface 122 at the proximal end
of the sheath 100. The splittable introducer 110 includes a tip end
111 and a ring 112. The ring 112 forms an opening to the splittable
introducer 110 and the ring 112 defines an inner surface that is
joined with the curved channel surface 122 of the support channel
120.
[0053] The splittable introducer 110 includes segments that open or
separate. Continuing to refer to FIG. 1, the splittable introducer
110 defines a conical exterior shape between the ring 112 and the
tip end 111 to aid insertion of the splittable introducer 110 into
an orifice. The pull-tab 140 is positioned at the proximal end of
the sheath 100 to provide a finger-grip for manipulation of the
sheath 100. For example, the pull-tab 140 may be used to withdraw
the sheath 100 from an orifice after insertion. The pull grip 140
may be a grip region having a gripping surface, finger-holds, or a
textured surface for increasing the friction between a user's
fingers and the sheath 100. The retention clasp 130 is adapted to
secure a cannula to the support channel 120 by providing, for
example, a friction fit or deflection fit against the shaft of a
cannula placed against curved channel surface 122.
[0054] In operation, the sheath 100 helps with insertion of a
cannula into stenotic cervix, or into a tight cervix, which is
sometimes the case for a nulliparous woman (a woman who has never
given vaginal birth). Additionally, the rigid support member 121
increases the stiffness of the sheath 100 and, in some instances,
aids in guiding the cannula through the cervix and into desired
position within uterine cavity when the cannula is placed in the
curved channel surface 122.
[0055] The sheath 100 may be constructed from a lubricious
material, such as Teflon (PTFE), or plastics compounded with
fluorinated oils. Alternatively, or additionally, a lubricious
coating can be applied to the sheath. Examples of material from
which the sheath can be formed include polypropylene,
polycarbonate, or other common plastics. Examples of materials from
which the lubricious coating can be formed include hydrogels,
hydrophilic coatings, such as Baymedix, Parylene, and other surface
modification technologies.
[0056] FIG. 2 is an illustration of the sheath of FIG. 1 with the
splittable introducer 110 in an open position. The splittable
introducer 110 of the sheath 100 is formed from a plurality of
conic segments 211 extending in a tapered triangular shape from the
ring 112 to the tip end 111 of the splittable introducer 110. Each
of the conic segments 211 forms a portion of the cone shape of the
splittable introducer 110, and the plurality of conic segments 211
are normally in a closed positioned (as shown in FIG. 1) to
maintain a small diameter at the tip end 111 during insertion. The
plurality of conic segments 211 are formed by longitudinal cuts 212
in the splittable introducer, forming edges 213 that enable each
conic segment 211 to be deflected away from the central axis of the
splittable introducer 110, as shown in FIG. 2, by an object being
pushed through the interior cavity of the splittable introducer
110.
[0057] FIGS. 3A-3D are illustrations of a cannula 300 being
inserted into the sheath 100 of FIG. 1. As shown in FIGS. 3A and
3B, the cannula 300 is placed on the curved support surface 122 of
the sheath 100. The cannula 300 includes a proximal end connector
330, a shaft 320 and a distal tip 310. The distal tip 310 of the
cannula is positioned adjacent to the ring 112 of the splittable
introducer 110.
[0058] FIG. 3C shows the distal tip 310 of the cannula 300 inserted
through the splittable introducer 110 of the sheath 100 until the
distal tip 310 extends beyond the tip 310 of the splittable
introducer. FIG. 3C shows the segments 211 of the introducer 110
are split by the distal tip 310. FIG. 3C shows the distal tip 310
and the shaft 320 of the cannula 300 pushed through the splittable
introducer 110 until the proximal end of the sheath 100 is close to
the proximal end of the cannula 300. The shaft 320 of the cannula
300 is secured to the sheath 100 by the retention clasp 130.
[0059] In an exemplary operation, the cannula 300 is placed within
support channel 220 of the sheath 100, just proximal of splittable
introducer 110, as shown in FIG. 3A, with tip end 111 of the
splittable introducer 110 prepared to be inserted into a cervix of
a patient. Next, the cannula 300 and sheath 100 are advanced
through the vaginal canal until the collapsed splittable introducer
110 is inserted into a cervical canal (through most or all of
cervical canal) of the patient, with the splittable introducer 110
helping to open the cervical canal as the increasing diameter of
the splittable introducer 110 is introduced though the cervix. In
some instances, the rigid support member 121 includes depth
markings to indicate the length of the sheath 100 inserted into the
patient. Next, the cannula 300 is advanced along the support
channel 120 and through the splittable introducer 110 until the
distal tip 310 of the cannula 300 is aligned with distal tip end
111 of the splittable introducer 110. This expands the splittable
introducer 110 and thereby further dilates the cervical canal. This
configuration is shown in more detail in FIG. 3E.
[0060] Once distal tip 310 of the cannula 300 reaches a desired
depth, the proximal end of the shaft 320 of the cannula 300 is
secured within the retention clasps 130 of the sheath 100. This
helps to effectively increase the stiffness of the cannula, which,
can be advantageous for positioning the cannula within the cavity.
The cannula 300 can be further advanced within the support channel
120, as shown in FIG. 3D.
[0061] Once in position, the cannula 300 can be oriented or rotated
to a desired position, as guided by the stiffness of the
introducer. The increased stiffness acts to resist the force
applied to the cannula by the cervix, allowing motion at the
proximal end of the cannula to translate to the motion at the
distal end, as opposed to motion at the proximal end causing the
cannula to bend at the cervix rather than move the distal end.
Diagnostic procedures can then be performed, for example, acquiring
images of the uterine cavity with the distal tip 310 of the cannula
300, and finally the cannula 300 and sheath 100 are removed from
the patient. The cannula 300 and sheath 100 can be removed
together, at the same time, from the cervix by pulling on the
cannula 300 and on the pull-tab 140 of the sheath 100, or the
sheath 100 can be removed from the patient while the cannula 300 is
still inserted within the cervix and/or uterine cavity (e.g., after
advancement of the cannula to the desired position and before
diagnostic procedures, or after diagnostic procedures) by pulling
on pull-tab; then remove cannula.
[0062] FIG. 3E is an illustration of the sheath 100 of FIG. 1
aiding insertion of a cannula 300 into the uterus 382 of a patient.
FIG. 3E shows sheath 100 present in the vaginal cavity 386 of a
patient with the introducer 110 of the sheath 100 inserted into the
cervix 381 of the patient. The distal tip 310 of the cannula 300 is
shown passed through the introducer 110 and into the uterus 383 of
the patient. The conic segments 211 of the introducer 110 are in a
deflected position as a result of the distal tip 310 of the cannula
passing through the introducer 110 and the deflection of the conic
segments 211 is dilating the cervix 381 of the patient. In this
configuration, the distal tip 310 of the cannula 300 is able to
conduct typical procedures involving the uterus interior surface
383.
[0063] While one embodiment has been discussed, many alternative
designs and features exist. For example, FIGS. 4A and 4B are
illustrations of a coiled sheath 400 with a coiled introducer 410
in a nominal position. As shown in FIG. 4A, the coiled sheath 400
forms a support shaft 420 and the introducer 410. The support shaft
420 defines a hollow tube 421 or curved surface 122 from the
proximal end of the coiled sheath 400 to a distal tip end 411 of
the introducer 410. The introducer 410 is detailed in FIG. 4B and
defines a frustoconical shape in the nominal state.
[0064] The coiled sheath 400 may be a plastic sheath 430 that coils
on itself. In its nominal state the introducer may have a length of
127 mm to 304.8 mm and an outer diameter of 0.5 mm to 30 mm. As a
tool or other member passes through the ID of the introducer the
coils unwind to dilate the cervix. Appropriate materials may
include polypropylene, polystyrene, polycarbonate and other common
medical device materials. In some instances, the tapered introducer
410 of the coiled sheath 400 is formed by maintaining the coiled
sheath 400 in a helical shape and applying heat to remove stresses
in the material and enable it to maintain the helical shape.
[0065] FIGS. 5A-5C are illustrations of a cannula 300 being
inserted into the sheath of FIG. 4A. FIGS. 5A and 5B shows the
distal tip 310 of the cannula 300 positioned to be inserted in the
proximal end of the hollow tube 421 of the support shaft 420. FIG.
5C shows the distal tip 310 of the cannula 300 inserted through the
coiled sheath 400 until it is located at the distal tip end 411 of
the introducer 410. Passage of the cannula causes radial expansion
of the introducer.
[0066] In operation, the coiled sheath 400 aids insertion of a
cannula into stenotic cervix, or into a tight cervix, which is
sometimes the case for a nulliparous woman. First, the coiled
sheath 400 is mounted onto the distal end 310 of the cannula 300.
Then, the cannula 300 and coiled sheath 400 are advanced through
the vaginal canal of the patient until the distal tip end 411 of
the elongated introducer 410 of the coiled sheath 400 is inserted
into cervical canal (through all of cervical canal or just past
distal end of cervical canal) of the patient. The introducer 410
helps to open the cervical canal. In some instances, the sheath 400
is introduced to the cervix prior to the introduction of the
cannula 300 to the sheath 400. Next, the cannula 300 is advanced
through the hollow tube 421 of the coiled sheath to a desired
distance within uterine cavity, which causes the elongated
introducer 410 to radially expands the coiled sheath 400, thereby
dilating the cervix. Once in place, the cannula 300 can be oriented
or rotated to a desired position, enabled by the stiffness of the
coiled sheath, and diagnostic procedures can be performed, such as
acquiring images of the uterine cavity with the distal end 310 of
cannula 300. Finally, the cannula 300 and coiled sheath 400 are
removed from the patient. In some instances, the cannula 300 and
coiled sheath 400 are removed from the patient together. In some
instances, the coiled sheath 400 is removed from the patient prior
to the cannula. In this case, the coiled sheath 400 can be unwound
to remove the coiled sheath 400 from the cannula.
[0067] While the coiled sheath 400 has been described as having a
tapered introducer 410, in some instances the introducer 410 is
cylindrical.
[0068] While the sheath 100 and 400 have been described as being
used to facilitate the entrance of hysteroscopy into cavities, they
could alternatively be used as introducers for facilitating the
insertion of other medical devices, such as cardiac catheters,
laparoscopes, and cystoscopes into small openings, such as
strictures or sphincters. In some instances, the introducer 110 has
a cylindrical shape. In some instances, the introducer 110 has a
shape suitable for entry into a small opening and subsequently
dilating the small opening by expanding the outer diameter of the
introducer 110.
[0069] While the sheath 100 has been described as being removed
from the patient while the cannula 300 is still inserted within the
cervix 381 and/or uterine cavity 383 by translating the sheath 100
along the cannula 300, other features that allow the introducer 110
to be separated from the cannula 300 and removed from the patient
separately from the cannula 300 can alternatively or additionally
be used. In some embodiments, for example, the sheath is provided
with a perforated slit that extends along the length of the sheath.
While the sheath 100 has been described as having a support channel
120, in some embodiments the sheath 100 includes a tubular body
adapted to accept the cannula 300. FIGS. 6A and 6B are
illustrations of a sheath 600 including a perforated support tube
620 (including longitudinal perforations 690 visible along a top
portion of the support tube 620). FIG. 6A is a perspective view
illustration of the sheath 600 and FIG. 6B is an enlarged
perspective view illustration of the introducer 610 of the sheath
600 showing the introducer 610 in a deflected position. The support
tube 620 allows the cannula 300 to pass though the sheath 600 and
into the introducer 610. In some embodiments, the sheath 600 can be
separated from the cannula 300 (internal, not shown) by breaking
the perforations 690 (shown as direction arrows 691) along the
support tube 620. Because the perforations 690 intersect the cuts
612 in the introducer 610 forming the segments 611, the entire body
of the introducer 600 can be split by the separating along
perforations 690. With the perforations 690 broken, the sheath 600
can be removed from the cannula (not shown).
[0070] In an alternate embodiment, the sheath 600 has a
longitudinal cut or split along the length of the sheath (e.g.,
along the location of perforations 690). In this alternate
embodiment, the sheath 100 is constructed from a material
sufficiently pliable to enable the sheath 600 to be removed from a
cannula 300 by separating the sheath 600 along the split enough to
pass the shaft 320 of the cannula 300 through the split.
[0071] While the sheath 100 has been described as having a one-part
construction, in some embodiments the sheath 100 includes two or
more parts coupled together to form the sheath 100. In certain
embodiments, the sheath has a two-part clamshell/hinged design
enabling separation of the sheath 100 about a hinge. FIG. 7A-7C are
illustrations of a sheath 700 including a hinged support tube 720
having a hinge 770 running longitudinally along the support 720.
FIG. 7A is a perspective view illustration of the sheath 700 and
FIGS. 7B and 7C are cross-section views of the sheath 700 showing
the cannula 300 in the hinged support tube 720. FIG. 7B shows a top
half 721a of the sheath 700 is, for example, hinged to a bottom
half 721b of the sheath 700 by a hinge 770 that extends along the
length of the sheath 700. The hinge 770 intersects the cuts 712 in
the introducer 711 forming the segments 711, thereby enabling the
top half 721a and bottom half 721b of the body of the sheath 700 to
rotate about the hinge 700. Separating the top half 721a from the
bottom half 721b (as indicated by arrows 723a,b) enables the
removal or insertion (as indicated by arrows 728) of the cannula
300 to the sheath 700.
[0072] While the sheath 100 has been described as a disposable
sheath, in some embodiments the sheath is reusable.
[0073] While the sheath 100 has been shown as including a retention
clasp 130 at the proximal end of the support channel 120, the
retention clasp 130 can alternatively be integrated with the
support channel 120 between the introducer 110 and the proximal end
of the sheath 100. In some embodiments, the retention clasp 130 is
a strap or elastic member placed across the cannula 300 after the
cannula is placed in the support channel 120. While the sheath 100
has been described as having a retention clasp 130, the sheath
could alternatively include no such retention clasp.
[0074] While the introducer 110 of the sheath 100 has been shown as
having triangular segments 211, different shapes can alternatively
be used. For example, the segments may be rectangular with
overlapping edges 213 in the relaxed state.
[0075] In some embodiments, the segments 211 of the introducer 100
are constructed from a pliable material. In some embodiments, the
cuts 212 between the segments 211 are filled with a mesh or
flexible material. In some embodiments, the segments 211 are
removeably coupled prior to use and are separated (e.g., along cuts
212) by the distal tip 310 of the cannula 300.
[0076] While the introducer 110 and the support channel 120 have
been shown as a single-piece, in some embodiments, the introducer
110 and support channel 120 are separate parts joined together to
form the sheath 100.
[0077] While the pull-tab 140 has been shown as being located at
the most proximal point of the sheath, the pull-tab 140 can
alternatively extend from a portion of the proximal end of the
sheath 100 that is distally spaced from the most proximal end
surface of the sheath.
[0078] While the pull-tab 140 has been described as being
positioned adjacent the vagina of a patient as the cannula 300 is
being inserted into the patient, in certain embodiments, the sheath
may have a length such that the proximal end of the sheath from
which the pull-tab 140 extends, may be located outside of the
patient during the insertion procedure.
[0079] While the sheath 100 has been described as having a pull-tab
140, the sheath could alternatively include no such pull-tab.
[0080] While the segments 211 of the introducer 110 have been
described as having a normally closed configuration, the segments
211 could alternatively have a normally open position. In the
normally open configuration, the segments 211 of the introducer 110
may be closed by a user's hand, for example, immediately prior to
insertion of the introducer 110. In some instances, the biased-open
segments 311 at least partially dilate the opening prior to
insertion of the cannula 300 by removing the force holding the
biased-open segments 311 in a closed position.
[0081] Referring now to FIGS. 1-3E, some examples of the present
design use the sheath 100 as a dilator that is expandable after
insertion. Once inserted into a patient, there could be a ratchet
or tab design that allows manual splitting to expand the sheath 100
within the cervix. FIGS. 8A-8E are illustrations of a sheath 800
having a dual-sheath design. The sheath 800 enables a user to
manually deflect the segments 811 of the introducer 810 prior to
the introduction of the cannula 300.
[0082] FIG. 8A shows a sheath 800 including an outer sleeve 821, an
inner sleeve 822, and an introducer 810. The outer sleeve 821
includes an outer pull-tab 841 at the proximal end of the outer
sleeve 821, and the inner sleeve 822 includes an inner pull-tab 842
at the proximal end of the inner sleeve 822. The inner sleeve 822
includes an inner ring 823 positioned to be inserted into an outer
ring 812 of the introducer 810. The inner sleeve 822 is positioned
to align with the outer sleeve 821 and slideably coupled, such that
translation of the inner sleeve 821 towards the introducer 811
(arrow 899 of FIG. 8B) engages the inner ring 823 with the segments
811 of the introducer. The inner ring 832 is sized to accept the
distal tip 310 of the cannula 300. FIG. 8B shows the inner sleeve
822 translated towards the introducer 810. As shown, in more detail
in FIG. 8E, the segments 811 of the introducer 810 are deflected
outward by the introducer 810 of the inner ring 823 into the
introducer 810.
[0083] FIG. 8C shows the proximal end of the sheath 800. The outer
sleeve 821 includes a retention feature 831 removeably securing the
inner sleeve 832 in a slidable configuration with the outer sleeve
821. The inner sleeve 822 includes a clasp 832 for removeably
securing the shaft 310 of the cannula 300 in the inner sleeve. FIG.
8D shows the underside of the proximal end of the sheath 800. The
inner sleeve 822 includes ratchet features 852 positioned to engage
with a pawl 851 on the outer sleeve 821. In operation, a user
grasps the pull-tabs 841, 842 and applies a force to squeeze the
pull-tabs 841, 842 together, thereby translating the inner sleeve
822 towards the outer sleeve 821 (as indicated by arrow 899).
Distal translation of the inner sleeve 822 engages the pawl 851
with the ratchet features 852, thereby preventing reverse (e.g.,
proximal) motion of the inner sleeve 822 when the user removes the
force. As shown in FIG. 8E, translation of the inner sleeve 822
towards the introducer 810 engages the inner ring 832 with the
segments 811 of the introducer 810, thereby deflecting the segments
811 in an outward direction.
[0084] In operation, the introducer 810 is inserted into the cavity
of a patient and the user translates the inner sleeve 822 towards
the introducer 810, thereby deflecting the segments 811 and
dilating the cavity of the patient. The ratchet features 852
maintain the deflection of the segments 811 by securing the
position of the inner sleeve 822. A cannula 300 is inserted though
the inner ring 832, through the introducer 810, and into the cavity
of the patient. The clasp 832 secures the cannula 300 to the sheath
800. To remove the sheath 800 from the patient, in some instances,
the cannula 300 is detached from the clasp 832 and the sheath 800
is removed from the patient while the cannula 300 remains inside.
In some instances, the sheath 800 and cannula 300 are removed
together, for example by the user pulling on the outer pull-tab 841
with the cannula 300 secured by the clash 832. In some instances,
the cannula 300 is detached from the clasp 832 and removed from the
patient, prior to subsequent removal of the sheath 800 from the
patient.
* * * * *