U.S. patent application number 14/055249 was filed with the patent office on 2014-04-24 for self-coiling stylet needle device.
This patent application is currently assigned to Cook Medical Technologies LLC. The applicant listed for this patent is Cook Medical Technologies LLC. Invention is credited to Michael S. Clancy, Nathaniel A. Irwin, Ronan Leahy, Darach McGrath, Ciaran Toomey.
Application Number | 20140114255 14/055249 |
Document ID | / |
Family ID | 49514051 |
Filed Date | 2014-04-24 |
United States Patent
Application |
20140114255 |
Kind Code |
A1 |
Irwin; Nathaniel A. ; et
al. |
April 24, 2014 |
SELF-COILING STYLET NEEDLE DEVICE
Abstract
A medical device includes an elongate single-wire memory-metal
body with a complete length that includes a proximal stylet length,
an intermediate self-coiling stylet length, and a distal stylet
length that is generally straight and non-self-coiling. The moment
of force of the self-coiling stylet length is less than the moment
of force of the medical endoscopy needle that is resistant to the
stylet's self-coiling force. The device may further include being
incorporated into an endoscopy needle system where the single-wire
stylet body is disposed through a lumen of a medical endoscopy
needle.
Inventors: |
Irwin; Nathaniel A.;
(Bloomington, IN) ; Clancy; Michael S.; (Limerick,
IE) ; McGrath; Darach; (Co. Tipperary, IE) ;
Toomey; Ciaran; (Co. Cork, IE) ; Leahy; Ronan;
(Co Limerick, IE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Cook Medical Technologies LLC |
Bloomington |
IN |
US |
|
|
Assignee: |
Cook Medical Technologies
LLC
Bloomington
IN
|
Family ID: |
49514051 |
Appl. No.: |
14/055249 |
Filed: |
October 16, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61716002 |
Oct 19, 2012 |
|
|
|
Current U.S.
Class: |
604/164.06 ;
604/164.01; 604/530 |
Current CPC
Class: |
A61B 17/3478 20130101;
A61B 10/0233 20130101; A61M 25/0102 20130101; A61B 10/04 20130101;
A61B 2010/045 20130101 |
Class at
Publication: |
604/164.06 ;
604/164.01; 604/530 |
International
Class: |
A61M 25/01 20060101
A61M025/01 |
Claims
1. A medical endoscopy needle system with stylet, the stylet
comprising: a medical endoscopy needle; and an elongate single-wire
memory-metal body with a complete length that includes a proximal
stylet length, an intermediate self-coiling stylet length, and a
distal stylet length that is generally straight and
non-self-coiling; where the moment of force of the self-coiling
stylet length is less than a moment of force inherent to the
medical endoscopy needle that is resistant to the stylet's
self-coiling force.
2. The system of claim 1, where the stylet is disposed through a
longitudinal lumen of the medical endoscopy needle, and the
self-coiling stylet length disposes the stylet to coil itself upon
removal from the lumen.
3. The system of claim 1, where the stylet comprises a rounded
generally atraumatic distal end tip.
4. The system of claim 1, where the memory metal comprises an alloy
selected from nickel-titanium, nickel-titanium-cobalt,
nickel-titanium-chromium, nickel-titanium-niobium,
nickel-titanium-hafnium, nickel-titanium-palladium,
nickel-titanium-platinum, nickel-titanium-iron, nickel-titanium
plus rare earth elements, iron-manganese-silicon, iron-platinum,
iron-nickel, iron-nickel-cobalt,
iron-nickel-cobalt-aluminum-tin-tantalum, and any combination
thereof.
5. The system of claim 1, where the self-coiling length forms one
or more coils having an outer diameter of about 7 cm to about 20
cm.
6. The system of claim 1, where the generally straight distal
length is no more than about 10% of the complete length.
7. The system of claim 1, where the self-coiling intermediate
length comprises up to about 95% of the complete length.
8. The system of claim 1, comprising a stylet with a complete
length of about 180 cm, a generally straight distal length of about
2 cm to about 20 cm, and a generally straight proximal length of
about 5 cm to about 14 cm.
9. The system of claim 1, where the stylet comprises a
tissue-piercing distal end tip.
10. The system of claim 9, where the distal end tip is a sharp,
beveled tip.
11. The system of claim 1, where the proximal length includes a
proximal end shaped to form a loop including at least one portion
that is generally perpendicular to a longitudinal axis of the
stylet.
12. The system of claim 11, where the loop is configured for use as
a proximal stylet handle and is disposed at a distance from a
stylet distal end such that the distal stylet end aligns with a
distal needle end when the loop contacts a proximal end of the
needle.
13. The system of claim 1, where the intermediate self-coiling
stylet length, when unconstrained, forms a plurality of coils as a
spiral wherein each coil has substantially the same outer
diameter.
14. The system of claim 1, where the intermediate self-coiling
stylet length, when unconstrained, forms a plurality of coils as a
spiral wherein each coil has a smaller outer diameter than a more
proximal adjacent coil, and the coil diameters decrease likelihood
of tangling or binding of the unconstrained stylet length.
15. The system of claim 1, where at least one coil of the
intermediate self-coiling stylet length, when unconstrained, forms
at least one coil shaped as a generally circular, generally
elliptical, generally oval, or generally obround shape.
16. The system of claim 15, where a coil immediately adjacent to
the at least one coil is disposed at a slight pitch relative
thereto, includes a different coil diameter in at least one
dimension, or any combination thereof.
17. A stylet comprising: an elongate single-wire memory-metal body
with a complete length that includes a proximal stylet length, an
intermediate self-coiling stylet length, and a distal stylet length
that is generally straight and non-self-coiling; where the
intermediate self-coiling stylet length comprises no more than 95%
of the complete length and, when unconstrained, defaults by a
memory-metal-imposed moment of force to form at least one coil with
an outer diameter of about 7 cm to about 20 cm.
18. The stylet of claim 17, where a distal end tip of the distal
stylet length is configured with a sharp beveled end.
19. The stylet of claim 17, where at least one coil of the
intermediate self-coiling stylet length, when unconstrained, forms
at least one coil shaped as a generally circular, generally
elliptical, generally oval, or generally obround shape.
20. The stylet of claim 17, where the memory metal comprises an
alloy selected from nickel-titanium, nickel-titanium-cobalt,
nickel-titanium-chromium, nickel-titanium-niobium,
nickel-titanium-hafnium, nickel-titanium-palladium,
nickel-titanium-platinum, nickel-titanium-iron, nickel-titanium
plus rare earth elements, iron-manganese-silicon, iron-platinum,
iron-nickel, iron-nickel-cobalt,
iron-nickel-cobalt-aluminum-tin-tantalum, and any combination
thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a non-provisional application which
claims priority to U.S. provisional application Ser. No.
61/716,002, filed Oct. 19, 2012, which is incorporated by reference
herein in its entirety.
TECHNICAL FIELD
[0002] Embodiments disclosed herein generally relate to a medical
endoscopic needle and stylet system. More particularly, the
disclosed embodiments relate to a self-coiling stylet.
BACKGROUND
[0003] Fine needle aspiration (FNA) and fine needle biopsy are
diagnostic biopsy procedures used to obtain a sample from a target
site in a patient body. A fine needle (e.g., 19-gauge to 25-gauge)
is directed to a target site, and suction is applied to the
proximal end of a lumen of the needle to aspirate cells through its
distal end. The procedure typically is far less invasive than other
biopsy techniques, whether performed percutaneously (e.g., to
sample a suspected breast tumor or subcutaneous lesion) or
endoscopically (e.g., to sample a suspected cholangiocarcinoma via
a duodenoscope). Moreover, advances in endoscopic ultrasound (EUS)
technology have helped physicians and patients by providing
enhanced ability of a physician to visualize a biopsy needle to
obtain a sample of material from a target site without requiring an
open incision or use of large-bore needles and/or percutaneous
trocars.
[0004] In order to provide desirable pushability and trackability
for these small-bore sample-collection needles, and to prevent
inadvertent (e.g., early and/or late) collection of tissue in one
or more distal needle openings, a stylet is typically provided
through the length of the needle lumen. After the distal end
opening(s) of the needle is/are directed to a target location via a
medical endoscope such as a duodenoscope or other
minimally-invasive endoscope device, the stylet is withdrawn and a
syringe or other modality is attached to the proximal needle end
for generating vacuum through the needle lumen to facilitate sample
collection by drawing sample material into the distal end
opening(s) of the needle. Stylet-management may pose challenges
during such procedures.
[0005] Specifically, a nurse or other person assisting the
physician conducting the endoscopic sample collection must
typically use both hands to withdraw the stylet from the needle
lumen. Because the stylet may be nearly 2 meters in length and is
non-sterile after having been inside the patient, it is usually
wound up by nurse as it is withdrawn. However, the default
configuration/orientation of existing stylets is generally
straight, which is to say that their default configuration is to
lie along an uncurved line in all longitudinal planes. As such,
stylets are biased to become unwound. This can pose a sharps injury
risk due to a sharp distal tip when a stylet springs loose from a
wound-up position, and/or it can become contaminated by contacting
other non-sterile surfaces. For this reason, the nurse must often
clip or otherwise secure the wound-up stylet. In the event that the
stylet must be reintroduced into the needle, both hands of the
nurse are required to control unwinding and to feed the distal
stylet portion back into the needle lumen. If the wound-up stylet
escapes the clip or other constriction, it may contact the floor or
another contaminating surface and have to be replaced by a sterile
stylet--increasing procedure time and expense.
[0006] Thus, it may be desirable to provide a stylet configuration
that will reduce procedure time, reduce the manual manipulation
required during a stylet/needle procedure such as endoscopic sample
collection (e.g., FNA, FNB), and that will reduce other risks
associated with loss of stylet control during such a procedure.
BRIEF SUMMARY
[0007] The needs described above are met by certain embodiments of
the presently described and claimed invention. In one aspect,
embodiments disclosed herein include a medical endoscopy
sample-collection system including a single-wire memory metal
stylet disposed through a needle lumen, as well as methods for
using that system. In another aspect, embodiments disclosed herein
may include a single-wire memory metal stylet with a self-coiling
intermediate length. Additionally, in certain embodiments, a
self-coiling single-wire memory metal stylet may include particular
patterns of self-coiling that prevent tangling and enhance the ease
of manipulating the device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows a self-coiling single-wire-body stylet
embodiment;
[0009] FIG. 2 shows a self-coiling single-wire-body stylet as part
of a needle/stylet system embodiment; and
[0010] FIGS. 3A-3C show proximal end configuration embodiments of a
self-coiling single-wire-body.
DETAILED DESCRIPTION
[0011] Various embodiments are described below with reference to
the drawings, in which like elements generally are referred to by
like numerals. The relationships and function(s) of the various
elements of the embodiments may better be understood by reference
to the following detailed description. However, embodiments are not
limited to those illustrated in the drawings. It should be
understood that the drawings are not necessarily to scale, and in
certain instances details may have been omitted that are not
necessary for an understanding of embodiments disclosed herein,
such as--for example--conventional fabrication and assembly.
[0012] The invention is defined by the claims, may be embodied in
many different forms, and should not be construed as limited to the
embodiments set forth herein; rather, these embodiments are
provided so that this disclosure will be thorough and complete, and
will fully convey enabling disclosure to those skilled in the art.
As used in this specification and the claims, the singular forms
"a," "an," and "the" include plural referents unless the context
clearly dictates otherwise. The terms "proximal" and "distal" are
used herein in the common usage sense where they refer respectively
to a handle/doctor-end of a device or related object and a
tool/patient-end of a device or related object.
[0013] As used herein, the term "moment of force" refers to the
tendency of a force to coil, twist, or rotate an object and/or to
resist coiling, twisting, or rotation. Specifically, the term is
used to refer to the self-coiling force of a memory-metal stylet
along a length thereof and to refer to the resistance of a needle
to that self-coiling force along a corresponding length thereof.
The term "single-wire" refers to a structure that, along the distal
operating longitudinal length thereof, includes only a single
lengthwise wire with no other parallel, coaxial, or other wires
(e.g., differentiating it from the braided, coaxially coiled, and
other wire structures used in guidewires, catheter bodies, and
other wire-based structures).
[0014] One embodiment of a self-coiling stylet is described with
reference to FIG. 1, which shows a stylet 100. The stylet 100 is
constructed with an elongate single-wire memory-metal body with a
complete length that includes a proximal stylet length 102, an
intermediate self-coiling stylet length 104 including at least one
coiled loop--which may include a plurality of coiled loops, and a
distal stylet length 106 that is generally straight and
non-self-coiling. The distal end tip 108 is configured with a
sharp, tissue-piercing beveled geometry. In other embodiment, a
piercing tip may be conical or otherwise configured to penetrate
and/or cut into/through tissue. In still other embodiments, the tip
may be rounded and generally atraumatic, but preferred embodiments
are configured to complement the distal piercing/penetrating tip of
a needle and/or to extend beyond a needle body to form a leading
surface.
[0015] The memory metal may include an alloy selected from
nickel-titanium, nickel-titanium-cobalt, nickel-titanium-chromium,
nickel-titanium-niobium, nickel-titanium-hafnium,
nickel-titanium-palladium, nickel-titanium-platinum,
nickel-titanium-iron, nickel-titanium plus rare earth elements,
iron-manganese-silicon, iron-platinum, iron-nickel,
iron-nickel-cobalt, iron-nickel-cobalt-aluminum-tin-tantalum, and
any combination thereof. One preferred embodiment includes
superelastic nickel-titanium (nitinol) wire. The methods of
thermosetting or otherwise imposing a "memorized" shape onto
memory-metal alloys are well-known known in the art, and those of
skill in the art will be enabled by the present disclosure and
contemporary knowledge to configure stylets in keeping with the
presently claimed invention embodiments. The intermediate
self-coiling stylet length 104 may be configured to form one or
more parallel and/or spiraling/concentric loops that have a
circular, oval, elliptical, obround, and/or other rounded
geometry.
[0016] The intermediate self-coiling stylet length 104 preferably
will form the one or more loops with an outer diameter of about 7
cm to about 20 cm. This will provide for the coiled stylet easily
to be stored on the surface of one of the carts/trolleys commonly
used in endoscopy operating suites without impeding the movement of
personnel during the procedure and remaining conveniently
accessible for re-use if/as needed.
[0017] The exact dimensions and proportions of different stylet
embodiments may vary. For example, the length and outer stylet
diameter (across a transverse section of the single-wire body) will
be constructed and/or selected for compatibility with a particular
needle. A stylet being used with a 25-gauge needle will have a
different outer diameter than one for a 19-gauge or 22-gauge
needle. Common lengths will be about 160 cm to about 170 cm. The
outer diameter of the stylet 200 may range from about 0.012 inches
(about 0.3 mm) to about 0.036 inches (about 0.9 mm), for stylet
lengths ranging from about 850 mm to about 1850 mm.
[0018] One exemplary embodiment is a 170 cm long stylet having an
outer diameter of about 0.035 inches (about 0.89 mm). This sample
stylet embodiment includes an intermediate self-coiling length that
is about 154 cm. It also includes a distal straight length of about
16 cm, terminating in a sharp/penetrating beveled tip, and its
proximal length is not straight but is co-terminal with a proximal
portion of the self-coiling intermediate length. This configuration
provides for a desirable balance between the functional advantages
of the unique self-coiling design and the provision of a
non-self-coiling distal length that will behave predictably and
uniformly (in contrast, for example, with the non-uniform behavior
of a guidewire that will have at least a slight distal-end
curvature as required for its desired steerability/navigability
function). In other embodiments, a proximal length of an exemplary
stylet may be straight.
[0019] In certain preferred embodiments, a generally straight
distal stylet length is no more than about 10% of the complete
stylet length. In certain preferred embodiments, the self-coiling
intermediate length may include up to about 95% of the complete
stylet length. In some embodiments, the self-coiling length may be
about 80% to about 92% of the complete stylet length, with about 4%
to about 9% of the complete length being a substantially straight
distal length, and the remainder (if any) being a substantially
straight proximal length.
[0020] FIG. 2 shows an embodiment of a medical endoscopy needle and
stylet system 200 including a needle 250 extending from a needle
sheath 252 workably attached with a needle handle 248, and a
self-coiling stylet 201. The stylet 201 is constructed with an
elongate single-wire memory-metal body with a complete length that
includes a proximal stylet length 202 terminating in a cap 203, a
self-coiling intermediate stylet length 204, and a distal stylet
length (not shown, disposed within the needle lumen). The stylet is
shown as partially withdrawn from the lumen of the needle 250. The
self-coiling intermediate stylet length 204 is shown as forming a
generally oval spiral configuration, where each of the more
proximal loops includes an outer diameter about the same as or
slightly less than the immediately-more-distal adjacent loop. This
configuration will prevent tangling during removal of the stylet
201 from the needle lumen and/or during reintroduction of the
stylet 201 into that lumen. Although not shown, the self-coiling
intermediate stylet length 204 extends through a significant length
of the needle.
[0021] Other tangle-prevention features may include that the
self-coiling intermediate length is thermoset or otherwise imposed
with a shape configured to prevent tangling such as, for example,
one or more of a helical construction with a slight pitch imparted
to each of the coils, slightly-decreasing or increasing diameters
and/or curvatures of each successive coil, and slightly differing
shapes of the coils. Stated differently, a coil immediately
adjacent to at least a first coil may be disposed at a slight pitch
relative thereto, include a different coil diameter in at least one
dimension, or any combination thereof effective to prevent--or at
least minimize the risk of--tangling. As shown in FIG. 2, the
moment of force of the stylet 201 is less than the moment of force
of the needle 250, such that the self-coiling length of the stylet
within the needle lumen does not deflect or impose any curvature
upon the needle. Specifically, those of skill in the art will
appreciate that the needle 250 inherently has a moment of force
resisting curvature; this is overcome to varying degrees during use
(e.g., navigating the needle through an endoscope working channel),
but is--in the presently preferred embodiments--greater than the
"pro-curvature/self-curving"moment of force of the stylet 201.
Thus, as illustrated, the stylet 201 is disposed through a
longitudinal lumen of the medical endoscopy needle 250, and the
self-coiling stylet length 204 disposes the stylet to coil itself
upon removal from the lumen by a person operating the needle system
or assisting therewith.
[0022] The unique self-coiling feature presents several advantages
for the present embodiments over existing stylets. For example, it
helps reduce procedure time and activity level, because the nurse
or other person who removes the stylet from the needle does not
have to manually wind up, then hold, tangle, and/or clip the stylet
to prevent it from whipping around, falling to the floor, or
otherwise moving in a manner that will allow contamination and/or
make it more difficult and time-consuming to reintroduce the stylet
to the needle if needed. The presently disclosed configuration also
reduces complexity and procedure time if the stylet needs
reintroduced into the needle lumen (e.g., for the needle to be
repositioned without inadvertent sample collection). In contrast
with existing designs that require the handler to manually
detangle, unclip, or otherwise unencumber the stylet and utilize
both hands to feed the stylet back into the needle lumen, the
present embodiments allow one-handed reintroduction into the needle
with less time and less risk of the stylet flopping around and/or
contacting surfaces that it should not.
[0023] FIGS. 3A-3C illustrate configurations for the proximal end
terminus of a stylet according to the present embodiments. FIG. 3A
shows a configuration currently in use, with a proximal end region
of a stylet 301 including a polymer stylet cap 369. The stylet cap
369 provides a broad proximal terminus for the stylet 301 that
provides a handle for withdrawing the stylet 301 and prevents the
proximal end of the stylet 301 from traveling into the needle
lumen. This and other proximal-end structures may be used with
self-coiling stylets of the present disclosure.
[0024] For example, as shown in FIG. 3B, a proximal stylet end
structure 379 may be constructed as a loop including at least one
portion that is generally perpendicular to the longitudinal axis of
a stylet 301 and generally coplanar with an immediately adjacent
stylet length. This proximal loop 379 may be configured as a
handle. In one preferred embodiment, the loop 379 is disposed at a
distance from a stylet distal end such that the generally
perpendicular transition of the loop 379 to the rest of the stylet
301 will align with the proximal end of a needle (not shown) when
the distal stylet end aligns desirably relative to the needle's
distal end.
[0025] Another example, shown in FIG. 3C, is a proximal stylet end
structure 389 be constructed as a loop including at least one
portion that is generally perpendicular to the longitudinal axis of
a stylet 301, where the loop portion generally lies along a plane
that is not coplanar with an immediately adjacent stylet length,
and which plane may be perpendicular/transverse relative to the
immediately adjacent stylet length. This proximal loop 389 may be
configured as a handle. In one preferred embodiment, the loop
handle 389 is disposed at a distance from a stylet distal end such
that the generally perpendicular transition of the loop 389 to the
rest of the stylet 301 will align with the proximal end of a needle
(not shown) when the distal stylet end aligns desirably relative to
the needle's distal end.
[0026] Those of skill in the art will appreciate that embodiments
not expressly illustrated herein may be practiced within the scope
of the claims, including that features described herein for
different embodiments may be combined with each other and/or with
currently-known or future-developed technologies while remaining
within the scope of the claims. Although specific terms are
employed herein, they are used in a generic and descriptive sense
only and not for purposes of limitation unless specifically defined
by context, usage, or other explicit designation. It is therefore
intended that the foregoing detailed description be regarded as
illustrative rather than limiting. And, it should be understood
that the following claims, including all equivalents, are intended
to define the spirit and scope of this invention. Furthermore, the
advantages described above are not necessarily the only advantages
of the invention, and it is not necessarily expected that all of
the described advantages will be achieved with every
embodiment.
* * * * *