United States Patent [19]
`Dinh et al.
`
`US006074381A
`[11] Patent Number:
`[45] Date of Patent:
`
`6,074,381
`Jun. 13, 2000
`
`[54] CYLINDRICAL ROLLER STENT CRIMPER
`APPARATUS WITH RADLATION SHIELD
`
`[75] Inventors: Minh Q. Dinh, Union City; Todd H.
`Turnlund, Sunnyvale; Thomas H.
`Campbell, Redwood City, all of Calif.
`[73] Assignee: IsoStent, Inc., Belmont, Calif.
`
`[21] Appl. No.: 09/177,668
`[22] Filed:
`Oct. 22, 1998
`[51] Int. Cl." ............................. A61B 17/00; A61F 11/00
`[52] U.S. Cl. .................................. 606/1; 606/198; 29/235
`[58] Field of Search ................................ 606/1, 108, 198,
`606/191, 194; 53/204, 209, 211, 213, 214;
`29/235
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`5,437,083 8/1995 Williams et al. .
`5,836,952 11/1998 Davis et al. .
`
`Primary Examiner—Michael Buiz
`Assistant Examiner—William Lewis
`Attorney, Agent, or Firm—Beyer Weaver & Thomas
`[57]
`ABSTRACT
`A stent loading apparatus for loading a deformable stent
`onto a deployment device. The stent loading apparatus
`includes an elastic member defining a passage therein
`formed for longitudinal receipt of the deformable stent in an
`uncrimped condition. A first member includes a first com
`pression region; and a second member includes a second
`compression region positioned substantially adjacent the
`first compression region at a first position. At this first
`position, the elastic member and the deformable stent in the
`uncrimped condition may be received between the opposed
`first and second compression regions. The first compression
`region and the second compression region are further con
`figured to provide rolling support and compression of the
`elastic member during relative movement between the first
`position and a second position for rolling radial compression
`of the deformable stent onto the deployment device.
`
`55 Claims, 12 Drawing Sheets
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`
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`Page 1 of 25
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`EDWARDS LIFESCIENCES EX. 1225
`Edwards Lifesciences v. Boston Scientific Scimed
`U.S. Patent No. 6,915,560
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`U.S. Patent
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`Jun. 13, 2000
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`Sheet 1 of 12
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`6,074,381
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`Jun. 13, 2000
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`U.S. Patent
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`Jun. 13, 2000
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`Sheet 6 of 12
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`U.S. Patent
`U.S. Patent
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`Jun. 13, 2000
`Jun. 13, 2000
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`Sheet 8 of 12
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`Page 9 of 25
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`Page 9 of 25
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`U.S. Patent
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`Jun. 13, 2000
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`Sheet 9 of 12
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`U.S. Patent
`U.S. Patent
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`Jun. 13, 2000
`Jun. 13, 2000
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`Sheet 10 of 12
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`Jun. 13, 2000
`Jun. 13, 2000
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`Sheet 11 of 12
`Sheet 11 of 12
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`6,074,381
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`U.S. Patent
`U.S. Patent
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`6,074,381
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`1
`CYLINDRICAL ROLLER STENT CRIMPER
`APPARATUS WITH RADLATION SHIELD
`TECHNICAL FIELD
`The present invention relates, generally, to intravascular
`stents and, more particularly, to stent crimping apparatus
`with radiation shields for radioactive stents.
`BACKGROUND ART
`Percutaneous Transluminal Angioplasty (PTA) is a medi
`cal procedure for widening a stenosis or constriction of a
`bodily passage. The most common application is to widen
`the passage of a blood vessel, such as an artery, which has
`been constricted by the build-up of cholesterol fats or
`atherosclerotic plaque. When this medical procedure is
`applied to a coronary artery, it is referred to as Percutaneous
`Transluminal Coronary Angioplasty (PTCA).
`Typically, a tip mounted balloon of a balloon catheter is
`advanced over a guidewire to the stenosis. Once the balloon
`catheter is properly position, the balloon is inflated to
`compress the plaque against the vessel walls and widen the
`stenosis. Problems occur, however, when the dilatation of
`the occlusion forms fissures, flaps and/or dissections which
`may ultimately cause reclosure or restenosis of the vessel.
`To maintain vessel patency and/or strengthen the area
`undergoing angioplasty or other treatment, an intravascular
`prosthesis may be employed. These devices are usually
`introduced percutaneously, transported transluminally and
`positioned at a desired location within the widened stenosis
`of the patient. One form of an intravascular prosthesis is a
`radially expandable stent device which is typically posi
`tioned at the tip of a balloon catheter and is implanted by
`expansion of the balloon when the balloon and stent device
`are at the desired location. Expansion of the balloon portion
`of the catheter can simultaneously compress plaque at that
`location and expand the stent to its proper implantation size.
`The balloon portion of the catheter is then deflated and
`withdrawn from the vessel, leaving the implanted stent as a
`permanent scaffold to reduce the chance of restenosis.
`To adequately mount an unexpanded stent onto the bal
`loon catheter for delivery into the patient, the stent is
`“crimped” or otherwise radially collapsed sufficiently to
`attach it to the balloon. One technique is to crimp the stent
`onto the balloon catheter through the use of a pair of
`modified plier-like tools which crimp down on the unex
`panded stent. The performance of these tools, however, is
`not completely satisfactory since there is still a wide diver
`gence between application force, profile and stent diameter.
`Problems arise when excessive crimping forces are applied
`to the crimp pliers which can damage the stent and/or
`balloon catheter. This is especially problemsome given the
`minute size of the stents which are typically on the order of
`about one (1) mm to four (4) mm in diameter before
`crimping. Moreover, non-uniformity of the crimping may be
`experienced as well as the inability to determine when a
`reliable and uniform crimp has been achieved.
`In other instances, the stents may be pre-crimped or
`preattached onto their associated delivery balloon at the time
`of production by the manufacturer. While these devices
`more uniformly control crimping quality, a large inventory
`of stent-bearing angioplasty catheters must be maintained to
`accommodate the variety of stent types, diameters and stent
`lengths for each balloon catheter type. Thus, maintaining
`such an inventory is not only difficult to store, but can be
`very expensive as well.
`One of the most favored crimping techniques is manual
`crimping performed by the physician in the catheter labo
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`ratory. This process enables the physician to “feel” the crimp
`to determine the crimp quality. The proper crimping of a
`stent about a balloon catheter, however, is a technique
`acquired only through practice and can be affected by a
`variety of subjective conditions. Too much or too little
`pressure may be applied and the balloon and/or stent may be
`damaged, lost, or may not otherwise perform as desired
`during the procedure. In contrast, the physician may not
`apply sufficient crimping pressure to the stent to load it onto
`the balloon. During advancement through the vessel or upon
`deployment, an insufficiently crimped stent may slip or
`rotate on the catheter during, or in the worst case scenario,
`come off the balloon catheter entirely; the result of which is
`not desirable. Moreover, when applying radioactive or
`radioisotope embedded stents, direct manual handling by
`physicians and laboratory technicians should be avoided.
`
`DISCLOSURE OF INVENTION
`Accordingly, a stent loading apparatus is provided for
`loading a deformable stent onto a deployment device. The
`stent loading apparatus includes an elastic member defining
`a passage therein formed for longitudinal receipt of the
`deformable stent in an uncrimped condition. The stent
`loading apparatus further includes a first member having a
`first compression region; and a second member having a
`second compression region positioned substantially adjacent
`the first compression region at a first position. At this
`position, the elastic member and the deformable stent in the
`uncrimped condition may be received between the opposed
`first and second compression regions. The first compression
`region and the second compression region are further con
`figured to provide rolling support and compression of the
`elastic member during relative movement between the first
`position and a second position to radially compress the
`deformable stent onto the deployment device.
`In another aspect of the present invention, a stent loading
`apparatus is provided for loading a deformable stent onto a
`deployment device including a crimper body including a
`curvilinear first compression wall defining a bore portion;
`and a spindle member having a curvilinear second compres
`sion wall extending into the bore portion adjacent the first
`compression wall. The spindle member is rotatably coupled
`to the crimper body for relative rotation of the first com
`pression wall and the second compression wall between a
`first position and a second position. In the first position, the
`first compression wall and the second compression wall are
`sufficiently spaced to enable receipt of the deformable stent
`therebetween. In the second position, the opposed first and
`second compression walls are sufficiently spaced to roll and
`radially compress the stent onto the deployment device.
`In one configuration, a gear assembly is included which is
`formed to cooperate with the crimper body, the spindle
`member and the deployment device to provided for rolling
`support of the stent between the first position and the second
`position. The gear assembly preferably includes a drive gear
`coupled to the crimp roller, an internal gear coupled to the
`crimper body, and a spur gear driveably meshed between the
`drive gear and the internal gear. The spur gear is further
`coupled to the deployment device to facilitate movement of
`the stent between the first position and the second position.
`In yet another aspect of the present invention, a stent
`loading apparatus includes a roller housing having a first
`compression wall defining a longitudinally extending
`groove portion, and a crimp roller rotatably coupled to the
`roller housing. The crimp roller further includes a substan
`tially cylindrical second compression wall positioned adja
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`cent and substantially parallel to the groove portion. A drive
`mechanism is coupled between the crimp roller and the
`roller housing for relative rotation of the second compres
`sion wall and the first compression wall between a first
`position and a second position. Similar to the previous
`configuration, in the first position, the first compression wall
`and the second compression wall are sufficiently spaced to
`enable receipt of the deformable stent therebetween. In the
`second position, the opposed first and second compression
`walls are sufficiently spaced to roll and radially compress the
`stent onto the deployment device.
`Another aspect of the present invention, a stent apparatus
`is provided for use with loading onto a deployment device.
`The stent apparatus includes an uncrimped elongated stent
`having an uncrimped diameter; and a shrink tube having a
`longitudinal length longer than the stent. The shrink tube, in
`an unshrunk condition, is formed to have an unshrunk
`diameter larger than the uncrimped diameter of the stent for
`sliding receipt of the stent therein. After the shrinking
`procedure, the shrink tube is of a shrunk diameter smaller
`than the uncrimped diameter to secure the shrink tube
`longitudinally around the stent for support thereof for align
`ment and positioning of the deployment device in the
`uncrimped stent.
`One other aspect of the present invention provides a
`shielded stent crimping assembly for loading a radioactive
`stent onto a deployment device. This assembly includes a
`crimping mechanism adapted to crimp the radioactive stent
`onto the deployment device. A shielded crimper body
`defines a bore portion formed for receipt of the radioactive
`stent and the crimping mechanism therein. The crimper body
`and the crimping mechanism cooperate to substantially
`prevent the passage of radiation from the bore portion during
`crimping of the stent by the crimping mechanism.
`A method of crimping a stent in onto a deployment device
`is further provided comprising the steps of inserting the
`uncrimped stent into an elastic tube having a diameter larger
`than the diameter of the uncrimped stent; and compressing
`the elastic tube until the opposed interior walls of the elastic
`40
`tube contact the exterior walls of the uncrimped stent. The
`present inventive method further includes the step of com
`pressibly rolling the elastic tube and the uncrimped stent
`from an uncrimped condition to a crimped condition until
`the compressed stent is mounted to the deployment device.
`BRIEF DESCRIPTION OF THE DRAWING
`The assembly of the present invention has other objects
`and features of advantage which will be more readily
`apparent from the following description of the best mode of
`carrying out the invention and the appended claims, when
`taken in conjunction with the accompanying drawing, in
`which:
`FIG. 1 is an enlarged front elevation view, in cross
`section, of a first embodiment of a stent loading apparatus
`constructed in accordance with the present invention ori
`ented in a first position to enable receipt of an uncrimped
`stent and balloon catheter therein.
`FIG. 2 is a front elevation view, in cross-section, of the
`first embodiment of the stent loading apparatus of FIG. 1
`oriented in a second position to radially compress and roll
`the stent onto the balloon catheter.
`FIG. 3 is a fragmentary top perspective view of the first
`embodiment of the stent loading apparatus of FIG. 1 illus
`trating the stent being radially compressed and rolled onto
`the balloon catheter between a first member and a second
`member.
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`FIG. 4 is a side elevation view, in cross-section, of a
`second embodiment of a stent loading apparatus of the
`present invention employing a crimp roller.
`FIGS. 5A-5C are a sequence of enlarged front elevation
`views, in cross-section, of the second embodiment of the
`stent loading apparatus taken substantially along the plane of
`the line 5–5 in FIG. 4, and illustrating the stent loading
`apparatus during crimping movement between the first posi
`tion and the second positions.
`FIGS. 6A and 6B are a sequence of side elevation views,
`in cross-section, of a third embodiment of a stent loading
`apparatus of the present invention mating with a radiation
`shield device for a radioactive stent.
`FIGS. 7A-7C are a sequence of enlarged front elevation
`views, in cross-section, of the third embodiment of the stent
`loading apparatus taken substantially along the plane of the
`line 7–7 in FIGS. 6A and 6B, and illustrating the stent
`loading apparatus during crimping movement between the
`first position and the second positions.
`FIG. 8 is an enlarged, fragmentary, side elevation view, in
`cross-section, of an elastic tube stent loading embodiment of
`FIG. 1 employing a shrink fit tube to facilitate positioning of
`the uncrimped stent onto the balloon catheter.
`FIG. 9 is a side elevation view, in cross-section, of a
`fourth embodiment of a stent loading apparatus of the
`present invention including a gear assembly.
`FIGS. 10A and 10B are a sequence of enlarged front
`elevation views, in cross-section, of the fourth embodiment
`of the stent loading apparatus taken substantially along the
`plane of the line 10—10 in FIG. 9, and illustrating the gear
`assembly during crimping movement between the first posi
`tion and the second positions.
`FIGS. 11A and 11B are a sequence of enlarged front
`elevation views, in cross-section, of the fourth embodiment
`of the stent loading apparatus taken substantially along the
`plane of the line 11—11 in FIG. 9, and illustrating the crimp
`roller engaging the stent during crimping movement
`between the first position and the second positions.
`FIG. 12 is a side elevation view, in cross-section, of a fifth
`embodiment of a stent loading apparatus of the present
`invention.
`FIGS. 13A and 13B are a sequence of enlarged front
`elevation views, in cross-section, of the fifth embodiment of
`the stent loading apparatus taken substantially along the
`plane of the line 13—13 in FIG. 12, and illustrating a gear
`assembly during crimping movement between the first posi
`tion and the second positions.
`FIGS. 14A and 14B are a sequence of enlarged front
`elevation views, in cross-section, of the fifth embodiment of
`the stent loading apparatus taken substantially along the
`plane of the line 14–14 in FIG. 12, and illustrating the
`crimp roller engaging the stent during crimping movement
`between the first position and the second positions.
`FIGS. 15A and 15B are a sequence of enlarged front
`elevation views, in cross-section., of a dual, opposed crimp
`roller embodiment of the stent loading apparatus of FIG. 12,
`taken substantially along the plane of the line 13—13 in
`FIG. 12, and illustrating a dual gear assembly during crimp
`ing movement between the first position and the second
`positions.
`FIGS. 16A and 16B are a sequence of enlarged front
`elevation views, in cross-section, of the dual, opposed crimp
`roller embodiment of stent loading apparatus of FIG. 12,
`taken substantially along the plane of the line 14–14 in
`FIG. 12, and illustrating the dual crimp rollers engaging the
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`stent during crimping movement between the first position
`and the second positions.
`BEST MODE OF CARRYING OUT THE
`INVENTION
`While the present invention will be described with refer
`ence to a few specific embodiments, the description is
`illustrative of the invention and is not to be construed as
`limiting the invention. Various modifications to the present
`invention can be made to the preferred embodiments by
`those skilled in the art without departing from the true spirit
`and scope of the invention as defined by the appended
`claims. It will be noted here that for a better understanding,
`like components are designated by like reference numerals
`throughout the various figures.
`Attention is now directed to FIGS. 1–3, where a stent
`loading apparatus, generally designated 20, is provided for
`crimping and mounting a deformable stent 21 onto a deploy
`ment device 22 (only a portion of which is illustrated). The
`stent loading apparatus 20 includes an elastomeric or elastic
`member 23 defining a passage 25 therein formed for longi
`tudinal receipt of the deformable stent 21 in an uncrimped
`condition (FIG. 1). The stent loading apparatus 20 further
`includes a first member 26 having a first compression region
`27, and a second member 28 having a second compression
`25
`region 30 positioned substantially adjacent the first com
`pression region 27 at a first position (FIG. 1). In this
`arrangement, the elastic member 23 and the deformable stent
`21 in the uncrimped condition may be received between the
`first compression region 27 and opposite second compres
`sion region 30. These opposed compression regions 27 and
`30 are further configured to provide rolling support and
`compression of the elastic member 23 during relative move
`ment between the first position and a second position (FIGS.
`2 and 3) to radially compress the deformable stent 21 onto
`the deployment device 22.
`Accordingly, a stent loading apparatus is provided for
`crimping an uncrimped stent onto a deployment device, such
`as a balloon catheter, which employs an elastic member to
`facilitate radial compression and rolling support of the stent
`until it is properly mounted to the balloon in a crimped
`condition. This elastic tube, in combination with the com
`pressive rolling action, exerts a uniform distribution of
`opposed and compressive radial forces along the stent. Such
`uniformity of the crimp in the longitudinal direction assures
`maintenance of the stent on the deployment device, as well
`as facilitate proper expansion of the stent during deploy
`ment.
`In the preferred form, the elastic member 23 is provided
`by an elastic tube which is sufficiently radially flexible so
`that it may be compressed against the outer walls of the
`uncrimped stent 21. Moreover, the elastic tube must be
`capable of compressively gripping the stent when sufficient
`rolling pressure is applied to the exterior walls 31, 31' of the
`elastic tube 23 to cause a rolling motion of the stent about
`its longitudinal axis 32. Such materials (rubbers,
`thermoplastics, and thermosets) include silicon, natural
`rubber, polyurethane, polyethylene, nylon, poly propylene,
`polyester, or the like.
`The passage interior diameter of the elastic tube 23 is
`preferably sufficiently large to enable uninterfered insertion
`of the uncrimped stent 21 therein when the elastic tube is in
`a relaxed, uncompressed condition. Thus, the diameter of the
`tube passage 25 is preferably in the range of about 1% to
`about 200% larger than the outer diameter of the uncrimped
`stent. More preferably, the passage diameter is about 60%
`larger than the uncrimped stent diameter.
`
`35
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`6
`As viewed in FIGS. 1 and 2, the radial thickness of the
`elastic tube 23 is significantly greater than the radial thick
`ness of the stent by about a 10:1 ratio. This dimensional
`difference, together with the nature of the elastic material,
`facilitates protection of the stent during the compressive
`rolling action. The elastic tube 23 is also preferably longer
`than the uncrimped stent and balloon combination
`(hereinafter, the “stent assembly 33”) so that the compres
`sive rolling movement can be more uniformly distributed
`longitudinally therealong. However, it will be understood
`that the tube length may be shorter than the stent assembly
`33 without departing from the true spirit and nature of the
`present invention.
`The compressive rolling forces urged upon the opposed
`exterior walls 31, 31' of the elastic tube 23 (FIGS. 2 and 3)
`may be applied by any first member and second member
`structure capable of generating the appropriate opposed
`compressive rolling forces. For example, the compressive
`rolling forces could be applied by a physician’s index finger
`and thumb rolling back and forth in a reciprocating manner.
`FIG. 3, in contrast, illustrates the first and second member
`26, 28 as two opposed plates compressing the elastic tube 23
`therebetween, and moving in opposite directions of arrows
`34, 34' to produce the necessary rolling motion in the
`direction or arrow 35. To facilitate traction, the plate sur
`faces may be coated with an elastic material (rubbers,
`thermoplastics, and thermosets), such as silicon, natural
`rubber, sand paper, etc., to roll and compressively crimp the
`stent. Additionally, to facilitate traction, the plates may be
`machined or knurled to have a textured surface to increase
`friction between the tube and plate.
`A method of crimping a stent in onto a deployment device
`is thus provided comprising the steps of inserting the
`uncrimped stent 21 into an elastic tube 23 having an inner
`diameter larger than an outer diameter of the uncrimped
`stent 21 (FIG. 1); and compressing the elastic tube 23 until
`the opposed interior walls of the elastic tube 23 contact the
`exterior walls of the uncrimped stent 21. As viewed in FIGS.
`2 and 3, the present inventive method further includes the
`step of compressively rolling the elastic tube 23 and the
`uncrimped stent 21 from an uncrimped condition to a
`crimped condition until the compressed stent 21 is mounted
`and sufficiently crimped to the deployment device 22.
`To crimp the stent, the rolling step may be performed by
`rolling the elastic tube 23 and stent assembly 33 in recip
`rocating back and forth directions, or the rolling step may be
`performed by rolling the elastic tube and the stent assembly
`in one direction.
`Referring now to FIGS. 4–5C, a second embodiment of
`the stent loading apparatus 20 of the present invention is
`illustrated for loading a deformable stent 21 onto a deploy
`ment device 22. In this embodiment, the first member 26 is
`provided a crimper body, generally designated 36, having a
`curvilinear first compression region, preferably wall 27,
`defining a bore portion 37; and a spindle member 38 having
`a curvilinear second compression region, preferably wall 30,
`extending into the bore portion 37 adjacent the first com
`pression wall 27. Collectively, these opposed first and sec
`ond compression walls define an annular gap 40 between the
`rotating components where the crimp is to be performed.
`The spindle member 38 is rotatably coupled to the crimper
`body 36 for relative rotation of the first compression wall 27
`and the second compression wall 30 between a first position
`(FIGS. 4 and 5A) and a second position (FIGS. 5B and 5C).
`In the first position, the first compression wall 27 and the
`second compression wall 30 are sufficiently configured to
`enable receipt of the deformable stent 21 therebetween in the
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`uncrimped position. In the second position, the opposed first
`and second compression walls are sufficiently configured to
`provide rolling radial compression of the stent 21 onto the
`deployment device 22.
`Accordingly, the stent 21 is caused to be radially com
`pressed and simultaneously rolled about its longitudinal axis
`during the relative rotational movement between first com
`pression wall 27 and second compression wall 30. Analo
`gous to the first embodiment, the first member is provided by
`the crimper body 36 defining the first compression wall 27,
`while the second member is provided by the spindle member
`38. During relative rotational movement between the
`crimper body 36 and the spindle member 38, the substan
`tially cylindrical first compression wall 27 rotates relative
`the cylindrical second compression wall 30 in a manner
`compressing and rotating the elastic tube 23 therebetween
`from the first position (FIGS. 4 and 5A) to the second
`position (FIGS. 5B and 5C) to compressively crimp the stent
`assembly 33.
`Briefly, while the application of the present invention is
`primarily described and illustrated in connection with the
`elastic tube embodiment, it will be appreciated that this tube
`may be excluded so that the crimping operation is performed
`directly upon the stent by the opposed first and second
`compression walls 27, 30. In this arrangement, however, the
`protective buffer provided by the elastic tube as well as the
`enhanced traction between the uncrimped stent 21 and the
`compression walls is eliminated.
`Crimper body 36 is preferably composed of a rigid
`material or the like having low level radiation shielding
`properties to function as a radiation shield when radioactive
`stents are being crimped. This material is preferably pro
`vided by an acrylic, leaded acrylic, glass, leaded glass,
`polycarbonate, stainless steel and lead, or the like of suffi
`cient thickness to provide shielding properties. For example,
`for an acrylic material to shield beta radiation, the thickness
`of first compression wall is preferably about 0.2 inches to
`about 0.5 inches. Such radioactive shielding qualities will be
`described in greater detail below.
`FIGS. 4 and 5A illustrate that crimper body 36 provides
`an elongated bore portion 37 extending longitudinally into
`an interior portion of the body from a proximal end thereof.
`At the distal end of crimper body 36 is a substantially
`cylindrical bearing port 41 extending into and communicat
`ing with bore portion 37. In this configuration, the second
`member 28 is provided by a crimp roller 28 of spindle
`member 38 which extends through port 41 and into bore
`portion 37, to position the second compression wall 30 of the
`crimp roller adjacent and opposed the first compression wall
`27.
`The diameter of bearing port 41 is sized and dimensioned
`for rotational receipt of a bearing portion 42 of spindle
`member 38 therein to rotatably couple the spindle member
`to the crimper body. This rotational coupling about the
`respective longitudinal axis is preferably an interference fit
`(i.e., sufficiently tight to substantially reduce substantial
`lateral movement, while sufficiently loose to enable relative
`rotational motion about the longitudinal axis). Alongitudinal
`axis of port 41 is substantially parallel to a longitudinal axis
`43 of the bore portion 37 so that upon rotational motion of
`the spindle member 38 the crimper body 36, the gap distance
`between the second compression wall 30 and the first
`compression wall 27 radially therealong remains substan
`tially constant for a cylindrical crimp roller. Moreover, a
`substantially uniform radial compressive rolling force is
`urged upon the stent 21 longitudinally therealong as the stent
`rolls between the first and second positions.
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`At a distal end of spindle member 38 is a crimper knob 45
`extending outside of crimper body 36 to provide manual
`access for rotative manipulation of the crimp roller 28
`relative the first compression wall 27. The diameter of knob
`45 is preferably greater than that of bearing port 41 so that
`a lip portion 46 of knob 45 functions as a stop to limit the
`depth of insertion of the crimp roller 28 into bore portion 37.
`The crimper knob 45 is preferably rigidly coupled to crimp
`roller 28 such that the rotation of the knob produces a 1:1
`ratio rotation of the crimp roller. It will be appreciated, of
`course, that a gear assembly or the like could be provided
`therebetween to alter the rotation ratio without departing
`from the true spirit and nature of the present invention.
`Moreover, the relative rotation motion between the spindle
`member and the crimper body may be driven by any
`conventional means as well.
`As best viewed in FIGS. 5A-5C, rotation of the spindle
`member 38 (in the direction of arrow 47 in these examples)
`causes the uncrimped stent assembly to be rollingly radially
`compressed or pinched between first compression wall 27
`and the opposed second compression wall 30. As the crimp
`roller 28 is rotated from the first position (FIG. 5A) to, the
`second positions of FIGS. 5B or 5C, for example, the stent
`assembly is caused to move in the annular gap 40 formed
`between the crimper body and the rotate spindle member in
`the direction of arrow 47, as well. Hence, not only is stent
`device properly uniformly compressed, at a substantially
`predetermined pressure between the first compression wall
`and the second compression wall, but the same is caused to
`be supportively rolled therebetween about its longitudinal
`axis for a uniformly distributed crimp as well.
`In this arrangement, access to the annular gap 40 of stent
`loading apparatus 20 is provided through an annular opening
`formed between the proximal end of crimp roller 28 and the
`proximal end of crimper body 36. In the first position (FIG.
`5A), the first compression wall 27 of crimper body 36 and
`the second compression wall 30 of crimp roller 28 cooperate
`to form an insertion cavity 48 therebetween sufficiently
`sized to enable longitudinal sliding insertion of the stent
`assembly 33 and/or the elastic tube 2