U.S. patent application number 15/202287 was filed with the patent office on 2016-10-27 for device for placing a vascular implant.
The applicant listed for this patent is Claude MIALHE. Invention is credited to Claude MIALHE.
Application Number | 20160310304 15/202287 |
Document ID | / |
Family ID | 33042045 |
Filed Date | 2016-10-27 |
United States Patent
Application |
20160310304 |
Kind Code |
A1 |
MIALHE; Claude |
October 27, 2016 |
DEVICE FOR PLACING A VASCULAR IMPLANT
Abstract
Provided is an implant placement device that includes an
envelope that contains an implant with a first auto-expandable
element expandable in a radial direction, a nose at a distal end of
the envelope, a sheath that confines a portion of the implant
therein and restricts expansion of a second auto-expandable element
of the implant, and a plunger. The sheath moves within the envelope
in a longitudinal direction perpendicular to the radial direction
and the plunger moves in the longitudinal direction within the
sheath with the implant positioned between an end of the plunger
and the nose, to discharge the implant from the device at a desired
position. The sheath slides in the longitudinal direction towards
the nose to bring the first auto-expandable element in contact with
an interior of the plurality of slots, thereby opening the
nose.
Inventors: |
MIALHE; Claude; (83300
Draguignan, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MIALHE; Claude |
83300 Draguignan |
|
FR |
|
|
Family ID: |
33042045 |
Appl. No.: |
15/202287 |
Filed: |
July 5, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10553007 |
Aug 7, 2006 |
9398916 |
|
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PCT/FR04/50118 |
Mar 22, 2004 |
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15202287 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 2017/1205 20130101;
A61B 2017/00575 20130101; A61B 17/12172 20130101; A61B 17/3468
20130101; A61B 17/0057 20130101; A61B 2017/00623 20130101; A61F
2/95 20130101; A61B 2017/00867 20130101; A61F 2002/9665 20130101;
A61B 17/12109 20130101; A61F 2/962 20130101; A61F 2/966 20130101;
A61B 17/3415 20130101; A61B 2017/00606 20130101; A61B 17/3439
20130101; A61B 2017/00592 20130101 |
International
Class: |
A61F 2/966 20060101
A61F002/966; A61B 17/12 20060101 A61B017/12 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 4, 2003 |
FR |
0350096 |
Claims
1. An implant placement device comprising: an envelope configured
to contain an implant, which includes a first auto-expandable
element, which is expandable in a radial direction; a nose
positioned at a distal end of the envelope having a plurality of
slots configured to divide the nose into a plurality of outwardly
opening segments; a sheath configured to confine a portion of the
implant therein and to restrict expansion of a second
auto-expandable element of the implant, wherein the sheath is
configured to move within the envelope in a longitudinal direction
perpendicular to the radial direction; and a plunger configured to
move in the longitudinal direction within the sheath with the
implant positioned between an end of the plunger and the nose, to
discharge the implant from the device at a desired position,
wherein the sheath is configured to slide in the longitudinal
direction towards the nose to bring the first auto-expandable
element in contact with an interior of the plurality of slots,
thereby opening the nose.
2. The device of claim 1, further comprising: a central residual
passage in the nose, which includes a shape memory that closes the
nose as a default position.
3. The device of claim 1, further comprising: a first grip
configured to move the envelope; and a second grip configured to
move to the sheath, wherein moving the second grip slides the
sheath within the envelope.
4. The device of claim 3, wherein the second grip is configured to
move in the longitudinal direction towards the first grip to expose
a front end of the first auto-expandable element of the
implant.
5. The device of claim 4, wherein the second grip is configured to
move the sheath away from the distal end of the envelope.
6. The device of claim 4, further comprising: a removable spacer
situated between said the first grip and the second grip to
maintain a space between the first grip and the second grip.
7. The device of claim 3, wherein the second grip is located closer
to a third grip than the first grip, wherein the third grip is
configured to move the plunger.
8. The device of claim 1, wherein the plunger is configured to
exert a second force against a rear end of the second
auto-expandable element, to discharge the implant.
9. The device of claim 1, wherein the implant further comprises a
hollow intermediate section.
10. The device of claim 9, wherein the implant is configured to be
maintained in the envelope with the first auto-expandable element
positioned closer to the nose than the hollow intermediate section,
with the intermediate section positioned closer to the nose than
the second auto-expandable element.
11. The device of claim 9, wherein the hollow intermediate section
is configured to be deformed by twisting upon rotation of the
sheath around a longitudinal axis of the device.
12. The device of claim 11, wherein the device detects an angle of
rotation of the sheath in relation to the envelope.
13. An implant placement device comprising: an envelope configured
to house an implant; a plunger; a sheath configured to confine a
portion of the implant to restrict expansion of an auto-expandable
element of the implant in a first position of the device and in a
second position of the device, wherein the envelope is disposed
around the sheath; and a nose positioned at a distal end of the
envelope and having a plurality of slots configured to divide the
nose into a plurality of outwardly opening segments, wherein a
longitudinal axis of the device is perpendicular to a radial
direction of expansion of the auto-expandable element of the
implant, and wherein: when in the first position of the device, the
implant is contained within the sheath between the plunger and the
nose, when in the second position of the device, the auto
expandable element is in contact with an interior of the plurality
of outwardly opening segments and is configured to open the nose
when the envelope is slid around the sheath, and when in a third
position of the device, the implant is discharged from the sheath,
when the plunger is moved in a longitudinal direction.
14. The device of claim 13, wherein the nose includes a shape
memory that closes the nose as a default position.
15. The device of claim 13, further comprising: a first grip
configured to slide the envelope on the sheath; and the first grip
configured to move towards a second grip to expose a front end of
the auto-expandable element of the implant.
16. The device of claim 13, comprising a spacer configured to move
between a first position of the spacer and a second position of the
spacer to stop a sliding movement of the envelope around the sheath
and to enable the sliding movement of the envelope around the
sheath, respectively, and wherein the spacer is in the first
position of the spacer when in the first position of the device,
and wherein the spacer is in the second position of the spacer when
the device is either in the second position of the device or in the
third position of the device.
Description
PRIORITY
[0001] This application is a Continuation Application of U.S.
patent application Ser. No. 10/553,007, which was filed in the U.S.
Patent and Trademark Office on Aug. 7, 2006, which is a National
Phase Entry of International Application No. PCT/FRO4/50118, which
was filed on Mar. 22, 2004, and claims priority to French Patent
Application Serial No. 0350096, filed on Apr. 4, 2003, the entire
disclosure of each of which is incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a device for placing an
implant.
[0004] 2. Description of the Related Art
[0005] In general, the related art includes the use of catheters or
any other instrument for placing an implant in a vessel of the
human or animal body.
[0006] The invention may be used for placing objects in a vessel in
the form of implants of the stent type or a vascular occlusion
device as presented for example in the document WO-A-02 19 926, or
implants of the coil type.
[0007] The invention can also apply to the placing of transparietal
occlusion devices for closing an opening in a vessel. The term
implant therefore applies here in the broad sense.
[0008] The placing of implants in a vessel requires the formation
of a transparietal opening (by penetration of the various layers of
tissue) to reach the internal lumen of said vessel.
[0009] In general, a dilation instrument is used for this purpose,
comprising a tapered end part able to produce a gradual increase in
the diameter of the passage produced in the vascular wall.
[0010] In general, the first step is to introduce a needle through
the vascular wall and a guide element, generally in the form of a
guide cable the end of which is held in position in the lumen, is
positioned. The guide cable makes it possible to insert other
instruments and to guide them through the opening produced in the
vascular wall. These instruments generally comprise an introducing
element with a central tapered end part enabling the diameter of
the parietal opening to be gradually increased. This central
tapered element is surrounded by an external sheath that ultimately
comes to be introduced through the vascular wall after the central
tapered part has produced its effect. The latter can then be
withdrawn while the external sheath is held in position and used to
perform the required surgical action.
[0011] For example, it is through the residual external sheath that
it is possible to effect the placing of a vascular implant. During
these operations, the guide cable can remain in position.
[0012] The usual technique described above has many drawbacks.
[0013] First, the tapered part for gradual introduction is
implemented in an element internal to the instrument until it
arrives at the diameter of the external sheath. In this context,
the internal tapered part encumbers the internal volume of the
external sheath throughout part of the operation, which in
particular excludes any possibility of the presence of another
functional or implantable element (for example a vascular implant)
in the internal space of the external sheath, before having
finalized insertion.
[0014] Another drawback of current inserters is that there remains
a dimension transition zone between the internal tapered element
and the external wall of the external sheath: this creates a
discontinuity in diameter, which may be detrimental to the
continuity of the insertion movement and damage the internal wall
of the vessels.
[0015] The aforementioned document WO-A-02 19 926 concerns a
vascular occlusion device comprising two expandable members for
fixing thereof by abutment on two portions of the wall of the
vessel. It furthermore comprises an intermediate part deformable in
torsion to a degree adjustable according to the relative positions
of the two expandable members so as to create a maximum stricture
zone defining a degree of occlusion. This document also presents a
method of use as well as an appliance for placing this occlusion
device.
[0016] The dilation instruments currently known prove to be
unsuitable for techniques of the type described in WO-A-02 19 926
in particular because they exclude the presence of a functional
element in the internal space thereof before the end of insertion
in the vessel.
[0017] From the document US-A1-2002 0042622, a medical device for
interventions of the anastomosis type is known. This device
comprises a trocar serving to transfix the wall of a vessel. This
trocar, with a tapered and openable end, does however have a highly
limited function according to this prior art since it serves only
for perforation.
[0018] A device for delivering a vascular occlusion plug is known
from the document U.S. Pat. No. 5,320,639. The device comprises a
channel in which the plug is inserted, which is placed in contact
with a lateral opening in the wall of a vessel. The channel may
have a tapered and openable end. This device is intended for a
specific use of occlusion through the outside of a vascular
vessel.
SUMMARY OF THE INVENTION
[0019] The present invention has been made to address at least the
above problems and/or disadvantages and to provide at least the
advantages described below.
[0020] The present invention remedies the drawbacks of the devices
known up to the present time. Thus it enables gradual insertion, an
increase in the diameter of the parietal opening and a centering in
a vessel by means of a single external member that also
participates in the release of the implant.
[0021] The present invention does not require the encumbering of
the internal space of the device since there is no tapered central
part to withdraw.
[0022] The internal space of the device is therefore kept free, for
the integration in particular, from the start, of an implant in the
device. It is thus possible, for example, to offer for sale an
instrument fully equipped with the implant to place.
[0023] It furthermore proves possible to perform several operations
in the vessel during the same surgery: by forming a shape-memory
system, the invention can provide a first insertion, and be closed
again in order to reach another vascular section and to be
re-employed therein.
[0024] The invention characteristically comprises a casing with a
dilation device fulfilling both a dilation function and a function
of holding the implant directly applied at least partially to the
internal wall thereof. In this way a compact assembly is produced
(fewer superimposed sheaths) facilitating placing while being
guidable by a conventional central guide of the guide cable
type.
[0025] The casing therefore also serves as a centering member
inside the vessel. A free space is moreover preserved at the center
of the assembly, for example for the passage of an expansion
balloon.
[0026] It should also be noted that the implant is fully protected
during the placing movements. When an expandable member is
released, the tapered nose of the casing ensures the
progressiveness of the release, preventing any "jump" effect
normally encountered through the abrupt variation in the diameter
of a stent when it is expelled from the housing thereof.
[0027] Other aims and advantages will emerge during the following
description of a preferred embodiment of the invention, which
however is not limitative.
[0028] The present invention concerns a device for placing a
vascular implant, comprising:
[0029] a device for dilating a vessel with an outer casing and a
tapered end part for insertion into the vessel, said end part
consisting of a nose formed at the distal end of the outer casing
and the dilating device, comprising means for opening the nose with
at least two longitudinal slots dividing the nose into several
deployable segments in order to open the nose,
[0030] an implant placed in the outer casing, characterized by the
fact that
[0031] the implant comprises an expandable member bearing on the
inner wall of the outer casing,
[0032] it has means for the translational movement of the implant
relative to the outer casing so that the expandable body bears on
the inner wall of the nose so as to deploy the segments
thereof.
[0033] This device may be presented in advantageous but
non-limitative variants indicated below:
[0034] the translation means comprise an inner sheath mounted so as
to slide in the outer casing and pushing the expandable member,
[0035] the implant comprises a second hollow expandable member and
a hollow intermediate part deformable in torsion,
[0036] the second expandable member bears on the inner wall of the
inner sheath,
[0037] the inner sheath is mounted slidably and rotatably in the
outer casing,
[0038] it comprises a gripping handle secured to the outer
casing,
[0039] it comprises a gripping handle secured to the inner
sheath,
[0040] the gripping handle of the inner sheath is situated at the
rear of the gripping handle and the outer casing and comprises a
removable spacer interposed between said handles so as to maintain
the spacing thereof,
[0041] the deployable segments are joined at isolated points along
the slots in the closed position of the nose,
[0042] it comprises one isolated join per slot between the
segments,
[0043] the nose comprises a residual central passage,
[0044] the nose has a shape memory so as to be closed by default
when the opening means are inactive,
[0045] it comprises a pusher mounted slidably in the inner sheath
and able to bear on the free end of the second expandable
member,
[0046] it comprises a gripping handle secured to the pusher
situated at the rear of a gripping handle secured to the inner
sheath and comprises a removable spacer interposed between said
handles in order to maintain separation thereof,
[0047] it comprises means for adjusting the angular position of the
inner sheath,
[0048] it comprises a central channel along the axis of the outer
casing for passage of a guide cable.
BRIEF DESCRIPTION OF DRAWINGS
[0049] The above and other aspects, features, and advantages of
certain embodiments of the present invention will become more
apparent from the following detailed description when taken in
conjunction with the accompanying drawings, in which:
[0050] FIG. 1 is a general side view of a placing device according
to the invention.
[0051] FIG. 2 is a view in section thereof.
[0052] FIG. 3 illustrates an example embodiment of a guide
cable.
[0053] FIG. 5 is a side view of an outer casing and FIG. 4 is a
front view thereof.
[0054] FIG. 6 illustrates a possible but non-limitative
configuration of an implantable device for vascular occlusion.
[0055] FIGS. 7 and 8 illustrate respectively side and front views
of a spacer that can be used in the placing device of the
invention.
[0056] FIG. 9 is a side view of an inner sheath that can be used
according to the invention, and FIG. 10 is a side view of a
pusher.
[0057] FIGS. 11 to 18 illustrate chronologically various phases of
use of the device according to the invention for placing an
implant.
[0058] In this context, FIG. 11 is a partial view in section of the
dilation device equipped with an implant.
[0059] FIG. 12 shows a step of modifying the configuration of the
instrument with removal of a spacer.
[0060] FIG. 13 shows a partial side view of the invention showing
an example embodiment of a tapered nose on the outer casing.
[0061] FIG. 14 shows the relative movement of various members of
the device of the invention for the opening of the nose.
[0062] FIG. 15 shows another phase of functioning of the placing
device according to the invention.
[0063] FIG. 16 is a detail view thereof.
[0064] FIG. 17 shows a last phase of use of the instrument with
removal of a second spacer.
[0065] FIG. 18 is a detail view thereof.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0066] Various embodiments of the present invention are described
in detail with reference to the accompanying drawings. The same or
similar components may be designated by the same or similar
reference numerals. Detailed descriptions of constructions or
processes known in the art may be omitted to avoid obscuring the
subject matter of the present invention.
[0067] The term dilation means, in the context of the invention,
both:
[0068] the dilation of a narrowed area by a solid instrument of
gradually increasing size. The tapered end makes it possible to
effect a channel-type broadening by forcing the gradual separation
of the walls or by extension of the separation of the tissues over
the penetration area. The profile of the dilator also enables the
instrument to be self-centered. This type of profile limits the
risk of lesion of the internal wall of the vessels, often covered
with calcified patches, use for "therapeutic" dilation as effected
by the inflation of a balloon with endoprosthesis. The pressure
exerted on the walls makes it possible to fracture the calcified
patches and to hope for an increase in caliber that persists after
deflation of the balloon. An incomplete result is supplemented by
the placing of an endoprosthesis.
[0069] The document WO-A 02 19 926 presents a special vascular
occlusion device comprising two expandable end members and an
intermediate part deformable under torsion by modification of the
relative angular positions of the two expandable end members.
[0070] In the following description, the use of the device
according to the invention for placing of the vascular occlusion
device indicated in the above document is described. This being the
case, this example of use is purely indicative and could not be
considered to be a limitation of the application of the present
invention. In particular, the device may have an implant of other
types, in particular with a single member expandable over the width
thereof The expandable member may be self-expandable or expandable
by balloon.
[0071] FIGS. 1 and 2 present in side view and cross-section a
placing device according to the invention. This device 21 comprises
in the front part thereof a device 1 for dilating a vessel.
Opposite the dilation device 1, the placing device 21 comprises a
part allowing manipulation by the practitioner. In particular,
handles 6, 7 and 12 are formed for gripping. The handle 12 may
integrate or receive various accessories such as a valve 22
preserving the fluid tightness of the instrument and a coupling 23
for connection of additional tubes.
[0072] The various elements constituting the dilation device 1 and
the placing device 21 according to the invention are described
below more precisely in the embodiment illustrated.
[0073] In this context, FIG. 3 shows the formation of a guide cable
11 (also referred to as a guide wire) that can be placed and
preserved in the central part of the device 1 and of the placing
device 21 throughout the phases of use of the invention.
[0074] FIGS. 4 and 5 show an outer casing 2 able to implement the
main body and to delimit an inner working space. The outer casing
comprises a distal end formed by a nose 14 with a tapered shape
configured to enable insertion in the vessel through the wall
thereof.
[0075] During use, the nose 14 is first of all in the default
closed position so as to constitute the tapered insertion profile.
When the nose 14 is sufficiently inserted in the vessel, opening
means are present to open the nose 14.
[0076] An example embodiment of these opening means is presented
below. Thus, in the context of FIGS. 4 and 5, the nose 14 is
equipped with a plurality of slots 16a, 16b, 16c, 16d implementing
a partitioning of the nose 14 into several segments 15a, 15b, 15c,
15d. The segments 15a, 15b, 15c, 15d thus have a relative freedom
of movement enabling the nose 14 to be opened in a movement
substantially corresponding to that of the petals of a flower.
[0077] The number of slots 16a, 16b, 16c, 16d and the length
thereof in the longitudinal direction of the device 1 are not
limited to the example illustrated.
[0078] Advantageously, the segments 15a, 15b, 15c, 15d of the nose
14 have a shape memory in order to regain the closed idle position
thereof when the opening means are no longer active. It is thus
possible to open and close the nose 14 on several occasions,
according to the requirements of the practitioner.
[0079] It is possible to provide other means for closing the nose
14, in the form of an active closure system for example by slipping
a wire into the various segments 15a, 15b, 15c, 15d between the end
of the nose 14 and a peripheral handle: the tension of the wire
closes the nose 14 and release may also serve for opening the nose
14.
[0080] At the opposite end of the outer casing 2, a handle 6 is
present for gripping by the operator. It should be noted that the
outer casing 2 delimits an inner space enabling, for example,
insertion of a vascular occlusion device 10 presented in FIG. 10
and comprising two expandable members 24, 25 as well as a flexible
intermediate part 26 deformable under torsion.
[0081] Docket: 2160-15 CON
[0082] The device 1 and the placing device 21 also comprise an
inner sheath 3 able to be mounted slidably in the internal space of
the outer casing 2. Just like the outer casing 2, the inner sheath
3 may consist of a substantially cylindrical portion with a
circular cross-section. The distal end of the inner sheath is left
free while the other end comprises a handle 7 for gripping by the
practitioner.
[0083] The invention also comprises a pusher 4 visible in FIG. 10
in a preferred embodiment in which it has a central channel 27
producing a residual passage in the core of the device as well as a
handle 12 receiving, in the case depicted, an end valve 22 and a
coupling 23 for ancillary connections. The pusher 4 is mounted
slidably in the internal space of the inner sheath 3.
[0084] Through this assembly, the configuration illustrated in
FIGS. 1 and 2 is arrived at. The handles 6, 7 and 12 are kept
separated by means of spacers 8, 9 formed removably so as to be
able to be successively removed during the surgery.
[0085] The guide cable 11 is here positioned in the residual
central channel 27 of the pusher 4 and its proximal end is
associated with a sleeve also allowing manipulation.
[0086] In the example illustrated, the opening of the nose 14 takes
place as follows. From a closed position, appearing for example in
FIG. 11, the practitioner removes the first spacer 8 so as to
enable the outer casing 2 to be withdrawn relative to the inner
sheath 3 until the handles 6, 7 are put in abutment. During this
withdrawal movement, the distal end of the inner sheath 3 exerts an
abutment on the internal wall of the outer casing 2 via an
expandable member 24 of the implant 10. This abutment causes the
deployment of the segments 15a, 15b, 15c, 15d of the nose 14 as is
clear from FIG. 14.
[0087] According to one possibility, isolated joins 17 are present
over the length of the slots 16a, 16b, 16c, 16d so as to preserve
an adjusted cohesion between the various segments 15a, 15b, 15c,
15d during the insertion phase. These joins 17 are nevertheless
designed so as to not to interfere with the deployment of the nose
14 and to make it possible to detach the various segments 15a, 15b,
15c, 15d through the abutment exerted by the inner sheath 3 when
the outer casing 2 is withdrawn.
[0088] Spot welds may serve as joins 17.
[0089] An example embodiment of a device for placing implants is
described more precisely below, in the non-limitative case of the
placing of vascular occlusion implants as shown in FIG. 6.
[0090] In this context, the implant 10 is positioned in the
internal space of the outer casing 2 before the start of the
operation. More precisely, the distal expandable member 24 is held
by the internal wall of the outer casing 2. At the rear, another
expandable member 25 is held in position against the internal wall
of the inner sheath 3. Advantageously, the rear end of the
expandable member 24 is put in abutment on the front end of the
inner sheath 3. In parallel, the rear end of the expandable member
25 is put in abutment against the distal end of the pusher 4. This
configuration is shown clearly in FIG. 11.
[0091] First, the practitioner inserts the nose 14 through the
vascular wall until it arrives at the required implantation. At
this stage, the spacer 8 is removed, which enables the practitioner
to withdraw the outer casing 2 relative to the inner sheath 3, by
means of the handle 6. This movement is illustrated in FIG. 12. It
gives rise to an abutment of the expandable member 24 and inner
sheath 3 on the internal wall of the outer casing 2 able to deploy
the nose 14 by separation of the various segments 15a, 15b, 15c,
15d. This situation is shown in FIG. 14, where the expansion of the
expandable member 24 once released can be noted.
[0092] At this level, the other expandable member 25 is also held
inside the inner sheath 3.
[0093] For an application to vascular occlusion, it is then
possible to effect a rotation of the inner sheath 3 so as to modify
the relative angular positions of the expandable members 24, 25. To
this end, the practitioner uses the handle 7 to modify the angular
position thereof. Naturally, in this application, it is necessary
for the inner sheath 3 to have a possibility of rotational movement
on the longitudinal axis of the device. Furthermore, it is
advantageous to provide means for adjusting the angular position of
the inner sheath 3, for example in the form of a reference 19
situated on the handle 7 opposite a plurality of graduations 20
formed on the external surface of the pusher 4 at a point visible
to the user. He can thus adjust the torsion imposed on the
intermediate part 26 in order to adjust the degree of occlusion,
which may also produce an adjustment of the length of the implant
10 by effecting a greater or lesser number of turns. This
possibility is illustrated by the double arrow in FIG. 16.
[0094] By removal of the spacer 9, the assembly consisting of the
outer casing 2 and the inner sheath 3 is withdrawn by a rearward
translation movement exerted at the handle 6 in order to move it
closer to the handle 12 as far as abutment.
[0095] At this stage, the abutment exerted by the pusher 4 on the
rear end of the expandable member 25 produces the release of said
expandable member 25 from the internal wall of the inner sheath 3.
This release causes the expansion of the member 25 for placing
thereof on the vascular wall. In this way the situation illustrated
in detail in FIG. 18 is arrived at, where the nose 14 is retracted
with respect to the inner sheath 3, the latter itself being
retracted with respect to the pusher 4. Naturally, here, the
relative retraction positions are accentuated for good
comprehension.
[0096] The guide cable 11 can be withdrawn or could have been
withdrawn previously. It will be noted that the nose 14 comprises a
residual central passage 14 visible in front view in FIG. 4 to
enable the cable 11 to be inserted and removed.
[0097] The spacers 8 and 9 here consist of the elements having an
annular cross-section in a lunar crescent of more than 180.degree..
The remaining opening makes it possible to act on the elasticity of
the material of the spacer in order to achieve removal thereof. An
example of a shape of the spacers 8, 9 is present in the case of
the spacer 8 in FIGS. 7 and 8. Naturally, another configuration is
possible with other means enabling the spacer to be removed.
[0098] The main constituents of the invention are, by way of
example, made from polyurethane or polyethylene.
[0099] While the present invention has been shown and described
with reference to certain embodiments thereof, it will be
understood by those skilled in the art that various changes in form
and detail may be made therein without departing from the spirit
and scope of the invention as defined by the appended claims.
* * * * *