Suture needle abstract
An endoscopic suture needle and related surgical endoscopic suturing
devices are to be used in conjunction with an endoscope. The invention
relates to suturing of internal body tissue as part of a surgical
procedure which may be diagnostic, therapeutic or both. In accordance
with the present invention, there is provided an endoscopic surgery
system comprising a temperature biased suture needle, a needle grasping
device, and an elongated catheter or other delivery tube, a endoscopic
surgery system configured for use in conjunction with a flexible
or rigid endoscope insertion member.
Suture needle claims
What is claimed:
1. An endoscopic surgical assembly comprising: a tubular member;
an elongate needle-grasping device slidably disposed at least partially
within a tubular member; a suture needle with at least a portion
of a needle being made of a temperature biased shape memory alloy;
and a temperature control system operable for selectively heating
or cooling a needle; wherein a temperature-biased needle may be
selectively transformed between a malleable and a rigid state for
use during surgery with an endoscope.
2. The endoscopic surgical assembly of claim 1 wherein a tubular
member is configured for insertion into the working channel of an
endoscope.
3. The endoscopic surgical assembly of claim 2 wherein a tubular
member includes one or more longitudinally disposed channels extending
at least partway along the wall of a tubular member.
4. The endoscopic surgical assembly of claim 3 wherein a proximal
inlet of a channel is operatively coupled with an injection port,
for injecting fluid.
5. The endoscopic surgical assembly of claim 4 wherein said injection
port is configured for coupling with an injection syringe.
6. The endoscopic surgical assembly of claim 3 wherein a distal
outlet of a channel is proximate a distal end of the tubular member.
7. The endoscopic surgical assembly claim 2 wherein the distal
end of the tubular member comprises a metal ring.
8. The endoscopic surgical assembly of claim 1 wherein the elongate
needle-grasping device includes a channel configured for directing
fluid to the needle.
9. The endoscopic surgical assembly of claim 1 wherein a temperature
control system is an electric system.
10. The endoscopic surgical assembly of claim 9 wherein the temperature
control system is coupled with the needle-grasping device.
11. The endoscopic surgical assembly in claim 9 wherein the temperature
control system is coupled with the tubular member.
12. The endoscopic surgical assembly of claim 11 wherein a tubular
member includes a metal collar positioned at a distal end thereof,
the collar being operatively coupled with a temperature control
system.
13. The endoscopic surgical assembly of claim 12 wherein the temperature
control system is comprised of at least one wire extending longitudinally
at least partially along a wall of the tubular member and operably
coupled with the metal collar.
14. The endoscopic surgical assembly of claim 1 wherein a needle-grasping
device includes a flexible or rigid elongated shaft, a handle mechanism,
and a jaw assembly with jaws.
15. The needle endoscopic surgical assembly of claim 14 wherein
a jaw of the jaw assembly is configured with a ridged internally
facing surface fashioned for grasping a suture needle.
16. The endoscopic surgical assembly of claim 14 wherein a elongated
shaft includes one or more push-pull wires, the wires at least one
of extending longitudinally through the shaft, or being incorporated
within a shaft.
17. The endoscopic surgical assembly of claim 14 wherein a push-pull
wire is operatively connected with the jaw assembly distally, and
with the handle mechanism proximally.
18. The endoscopic surgical assembly of claim 14 wherein the needle
grasping device includes a handle assembly, a handle assembly having
opposing scissor finger rings, operatively coupled with corresponding
leverage-joints that are, in turn, operatively coupled with at least
one push pull wire, a push-pull wire being operatively coupled with
jaws of a jaw assembly.
19. The endoscopic surgical assembly of claim 18 wherein separation
of the opposing scissor finger rings causes separation of a leverage-joints
and relaxation of the push-pull wire, causing a jaws to open.
20. The endoscopic surgical assembly of claim 19 wherein the approximation
of the opposing scissor finger rings causes approximation of a leverage-joints,
and applies a strong pull on the push-pull wire, bringing about
tight closure of the jaws.
21. The endoscopic surgical assembly of claim 14 whereby the jaws
are constructed with broader proximal and narrower distal ends.
22. The endoscopic surgical assembly of claim 14 whereby an inner
surface of the jaws is configured with at least one of teeth or
ridges.
23. An endoscopic suture needle, wherein a needle is comprised,
at least partially, of a temperature biased shape memory alloy.
24. The suture needle of claim 23 wherein the needle is comprised
of a shape memory alloy of nickel and titanium.
25. The suture needle of claim 23 wherein the needle is comprised
of a special ratio of Ni to Ti whereby a needle assumes a malleable
state when chilled, and a rigid state when heated.
26. The suture needle of claim 23 wherein a Ni to Ti ratio is such
that the transition temperature from malleable to rigid is between
30.degree. C. (.+-.3.degree.) and 39.degree. C. (.+-.3.degree.).
27. The suture needle of claim 23 wherein a Ni to Ti ratio is such
that the rigid start temperature (A.sub.s) is in the range of 30.degree.
C. and its rigid finish temperature (A.sub.f) is in the range of
39.degree. C.
28. The suture of claim 23 wherein the cross sectional configuration
of a portion of the suture needle is circular.
29. The suture needle of claim 23 wherein the cross sectional configuration
of a portion of the suture needle is rectangular.
30. The suture needle of claim 25 wherein the needle assumes its
rigid state at a temperature proximate body temperature.
31. The suture needle suture of claim 25 wherein the needle assumes
its rigid state at a temperature above body temperature.
32. The suture needle of claim 23 wherein said needle is coupled
at its proximal end with a suture thread.
33. The suture needle of claim 24 wherein the needle includes cavity
placed into a proximal end of the needle, and the needle is coupled
with a biocompatible glue.
34. A minimally invasive endoscopic suturing assembly comprising:
a tubular member; an elongate needle-grasping device slidably disposed
at least partially within a tubular member; a suturing needle wherein
at least a portion of a needle is made of a temperature biased shape
memory alloy; and a temperature control system operable for selectively
heating and cooling a needle.
35. A minimally invasive surgical method for suturing comprising:
(a) providing a medical treatment assembly including: an endoscope
insertion member; a tubular member; an elongate needle-grasping
device slidably disposed at least partially within a tubular member;
a suturing needle wherein at least a portion of a needle is configured
of a temperature biased shape memory alloy; and a temperature control
system operable for selectively heating and cooling a needle; (b)
inserting a distal end portion of a endoscope insertion member into
a patient; (c) inserting a tubular member in the endoscopic insertion
member with the needle being grasped by the needle grasping device;
(d) after visualizing target tissue in need of a suturing operation,
ejecting said needle grasping device and needle, with the needle
in a malleable state; (e) positioning a suture needle proximate
the target tissue; (f) selectively heating a suture needle by utilizing
a temperature control system, thereby transforming a needle to an
arcuate, rigid state; (g) manipulating a needle through target tissue
with the needle grasping device to perform a suturing operation;
(h) applying cold liquid to the needle, thereby transforming said
needle to a malleable state in preparation for withdrawal of a needle
through the endoscope insertion member.
36. The surgical method of claim 35 wherein selective heating of
the suture needle occurs via electricity conducted through a needle
grasping device.
37. The surgical method of claim 36 wherein selective heating via
electricity of a suture needle is performed by means of a metal
collar positioned proximate the suture needle.
38. The surgical method of claim 35 wherein a grasping device is
configured with a jaw assembly for grasping a suture needle.
39. The surgical method of claim 38 wherein a jaw assembly is configured
to engage a proximally located shaped end of a suture needle.
40. The surgical method of claim 39 wherein a proximally located
shaped end of the suture needle is one of a triangular, round or
rectangular cross section.
41. The surgical method of claim 35 wherein selectively heating
of a suture needle to transform it into its rigid state occurs at
a temperature proximate body temperature.
42. The surgical method of claim 35 wherein selectively heating
of a suture needle to transform it into its rigid state occurs at
a temperature above body temperature.
43. The surgical method of claim 35 wherein the shape memory material
may be transformed to its rigid state by heated fluid.
44. The surgical method of claim 35 wherein the shape memory material
may be cooled below the malleable state by cooled liquid.
45. The surgical method of claim 35 wherein the needle is selectively
heated by holding the needle with a heated needle-grasping device.
46. The surgical method of claim 35 wherein the needle is selectively
heated by holding the needle proximate to a heated element.
Suture needle description
[0001] This application claims the benefit of the priority of U.S.
Provisional Application Ser. No. 60/549275 filed on Mar. 2 2004
entitled "Temperature Biased Suture Needle," which application
is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a surgical instrument assembly
for use in suturing inside internal body cavities of a patient,
and more specifically to an instrument assembly for use in conjunction
with a flexible or rigid endoscope to suture tissue within the body.
This invention has particular applicability for suturing in conjunction
with an endoscope inside internal body cavities of a patient, for
example, inside the abdomen by gaining access through an existing
orifice.
BACKGROUND OF THE INVENTION
[0003] In a conventional abdominal surgical procedure, one or more
incisions are created in the abdominal wall in order to enter the
abdominal cavity. Surgical procedures to remove diseased tissue
or organs are currently performed via open or laparoscopic surgery.
In addition to major abdominal operations such as colon resection,
gall bladder removal, and stomach resections, surgery for morbid
obesity (bariatric surgery) is being performed with greater and
greater frequency due to the increasing prevalence of morbid obesity
and its complications.
[0004] The high incidence of obesity its related medical problems
have reached epidemic proportions in the United States affecting
more than 30% of the adult population and accounting for nearly
300000 deaths annually. Bariatric procedures most commonly performed
include vertical banded gastroplasty, gastric banding, and Roux-en-Y
gastric bypass (RNYGB). Morbidity and mortality resulting from these
operations is relatively high.
[0005] These complex and invasive surgical procedures require general
anesthesia, surgical incisions, lengthy periods of time in the hospital,
significant use of medication for management of postoperative pain
and lengthy periods of convalescence. Surgical procedures to treat
morbidly obese patients have a high incidence of complications and
thus limit the number of patients who can benefit from these procedures.
Surgery for morbid obesity is currently performed through a large
abdominal incision. The operation entails exclusion of a large portion
of stomach, and a bypass procedure of the small intestine. Oftentimes
the patient has had prior surgery causing adhesions, which bind
the intestines together. In that case the surgeon must first dissect
these adhesions and free the bowel in order to reach the operative
site.
[0006] While laparoscopic surgery, which is a less invasive procedure,
has become the standard of surgical care for numerous disease processes,
complications from laparoscopic bariatric surgery are comparable
to those resulting from open procedures. The surgery is technically
more difficult and takes two to three hours longer than the open
operation. Consequently longer anesthesia time is required, increasing
patient morbidity. In order to perform gastric bypass surgery laparoscopically,
the abdomen requires distention with air, which impinges on the
patient's lungs thereby decreasing breathing capacity.
[0007] Providing an option for surgery that may be performed through
an existing orifice via the flexible endoscope would offer a less
invasive approach. Because flexible endoscopic procedures are classically
performed under conscious sedation and do not require an incision
to enter the body, they are naturally less invasive. Consequently,
morbidity and mortality would be reduced, convalescence time and
hospital stay would be shortened, post-operative pain virtually
eliminated and cost savings provided.
[0008] Yet, such procedures are currently limited to examinations
that include biopsy and polypectomy within the lumen of the gastrointestinal
tract. One of the significant reasons for this limitation is the
lack of the ability, with current surgery assemblies and techniques,
to perform suturing and/or stapling through the narrow working channel
of the flexible endoscope.
[0009] Although there appear to be no commercial devices on the
market that enable suturing through the working channel of the flexible
endoscope, U.S. Pat. No. 5037433 to Wilk et al. describes an endoscopic
suturing device that comprises an endoscope and a needle having
a mechanical spring bias construction tending to bend the needle
into an arcuate configuration. The needle is disposed in a straightened
configuration while inside the endoscope. The surgical instrument
further comprises an ejector device in the form of an elongate flexible
rod member slidably disposed inside the inner tubular member proximally
of the needle for ejecting a needle, which mechanically assumes
an arcuate configuration subsequent to its ejection.
[0010] Based on the disclosure and drawings of the '433 patent,
the mechanical spring biased or elastic tendency of the needle tends
to bend a needle in an arcuate configuration. As such, this pre-stressed
plastic or metal needle may be deformed (i.e. straightened) by mechanical
stresses on the needle being confined in a generally straight biopsy
channel of an endoscope, deforming the needle to render it generally
straight. The mechanical stresses are provided and maintained by
the walls of the biopsy channel into which the needle is inserted.
Once the needle is ejected out of the biopsy channel by a rod, the
stresses are removed, and the free needle immediately assumes its
pre-stressed arcuate configuration under the direction of its normal
elastic properties.
[0011] The device described in the '433 patent presents the various
drawbacks and problems. First, the flexible endoscope is constructed
in such a fashion as to allow only a 1 cm "stiff length"
or less to pass through its biopsy or working channel. Any embodiment
with a stiff length longer than 1 cm will not be capable of being
passed through the working channel when the endoscope is bent, and
will prevent the flexible endoscope from bending when housed inside
its working channel. Consequently, only a device that is sufficiently
malleable to bend relatively easily along with the endoscope may
be passed through its working channel. Suturing requires a rigid
needle shaped in an arcuate form. When such a needle is plunged
into the target tissue in one location, it will exit the tissue
at a second location in a predictable manner because of the needle's
arcuate configuration and stiff or rigid state. Accordingly, there
are two important requirements that a suture needle must fulfill
if it were to be used through the working channel of a flexible
endoscope. On one hand, it must be malleable enough to be passed
through the working channel of a flexible endoscope while an endoscope
is bent to its maximum capacity, while on the other hand it must
assume a rigid arcuate state in readiness for the suturing operation
upon ejection. If the spring biased needle described in the '433
patent were to be sufficiently malleable to be passed through the
working channel of an endoscope, it would surely be too malleable
to enter and exit tissue in a reliable fashion. If a needle were
to be formed from a material stiff enough to effectively and consistently
enter and exit tissue, it would surely not be malleable enough pass
through the working channel of a flexible endoscope.
[0012] A further problem that the device described in the '433
patent presents is its lack of anticipation of the difficulty presented
in grasping the suture needle with the manipulation device. Just
as in open and laparoscopic surgery, a suture needle must be grasped
firmly so as not to rotate on its axis during the plunging of a
needle into tissue. If the needle is permitted to rotate on its
own axis it will only push against the tissue but will not enter
it. Grasping a needle with jaw-closure-force being transmitted through
a short rigid shaft, as is done during open or laparoscopic surgery
is significantly different from grasping a needle with closure force
being transmitted through a long flexible shaft. The latter forces
required to close the jaws tightly are infinitely greater than in
the former case. The '433 patent does not address such an issue.
No special construction of the needle's shaft to enhance grasping
is described, and the description of the grasping device does not
anticipate any of the abovementioned difficulty.
[0013] Lastly, the '433 patent does not address the attachment
of the suturing thread to the needle. Spring biased metals do not
behave as stainless steel does. In the case of the stainless steel
suture needle, the suture thread is inserted into a cavity at the
proximal end of the needle and the metal is crimped over the thread.
In the case of a needle made of a spring biased metal, the metal
is too soft to retain the thread by mere crimping.
[0014] Therefore, it would be desirable to address the shortcomings
and drawbacks of the prior art and to specifically provide an instrument
assembly for suturing in p laces internal to a patient's body utilizing
flexible or rigid endoscopes inserted primarily, though not exclusively,
through existing body orifices.
[0015] It is further desirable to provide such an instrument assembly
for performing surgery through said endoscope, whereby an instrument
assembly may be passed through the narrow, preferably flexible working
channel of said endoscope.
[0016] It is also desirable to address suturing concerns with a
needle that is malleable enough to go through the working channel
of the endoscope without inhibiting said endoscope's bending maneuverability,
and yet, for suturing, is a rigid arcuately-shaped needle for use
during a suturing operation.
[0017] It is still further desirable to grasp a needle with an
instrument that would be deliverable through narrow, convoluted
working channel of a flexible endoscope, and yet would be capable
of grasping the needle firmly and securely.
[0018] It is desirable to provide an associated method for suturing
through an endoscope, supplementing or replacing the more invasive
surgical procedures, and reducing the complications and drawbacks
of existing open or laparoscopic surgical procedures particularly
those performed for morbid obesity.
[0019] The benefits of the present invention in addressing the
drawbacks and shortcomings of the prior art and the objectives and
needs noted above will be more readily apparent from the description
and drawings of the invention set forth herein.
SUMMARY OF THE INVENTION
[0020] The present invention is directed to a surgical endoscopic
suturing system to be used in conjunction with an endoscope. The
invention relates to suturing of internal body tissues as part of
a surgical procedure which may be diagnostic, therapeutic or both.
In accordance with the present invention, there is provided an endoscopic
surgery system comprising a temperature biased suture needle, a
needle grasping device, and an elongated catheter or other delivery
tube, a endoscopic surgery system configured for use in conjunction
with an endoscope insertion member material that may become transformed
from a malleable to a rigid state and vice versa. As such, a suture
needle is sufficiently malleable to be passed through the working
channel of the flexible endoscope. When a needle is ejected from
the working channel in readiness for suturing, it may be treated
in a particular manner to transform a needle into a rigid state,
appropriate for suturing tissue.
[0021] In one embodiment of the present invention, the suture needle
is configured of a temperature biased shape memory alloy Nitinol
(NiTi). The Nitinol alloy selected for a needle takes on a desired
arcuate shape and stiffness appropriate for suturing when heated
to a certain temperature. When cooled below a specific temperature,
it does, in turn assume a malleable state. The ability to return
to the previously defined shape when subjected to the appropriate
thermal procedure is the basis upon which the temperature biased
suture needle functions in accordance with the principles of the
present invention. Accordingly, the temperature at which the suture
needle will be in a heated state may vary. For example, in one embodiment,
the suture needle is in a heated state at a temperature proximate
body temperature. In another embodiment, the suture needle is in
a heated state at a temperature above body temperature.
[0022] The needle-grasping device manipulates the suture needle.
Pursuant to a particular feature of the present invention, the needle-grasping
device is configured to firmly grasp the suturing needle, enabling
a needle's passage through the working channel of the endoscope
insertion member, and performance of the suturing operation in a
consistent and reliable manner. Pursuant to an embodiment of the
present invention, the needle-grasping device is made of a rigid
material such as stainless steel, and is comprised of a handle mechanism,
a long flexible shaft, and a jaw assembly. According to a particular
feature of the present invention, the jaw assembly is configured
such that the inner surfaces of the grasping jaws possess a series
of ridges, specially designed to firmly grasp the suture needle
thereby preventing its rotation on its own axis during the suturing
operation. The control mechanism for opening and closing the jaw
assembly is comprised of one or more wires traversing through the
shaft of a needle grasping device, a wires being configured to transmit
mechanical compressive and tensile forces to enable alternating
opening and closing of jaws. The wire(s) are operatively connected
to a handle mechanism proximally, and to jaw assembly distally.
[0023] In one embodiment of the needle-grasping device pursuant
to the present invention, the handle mechanism comprises two finger
rings operatively coupled with two leverage joints, a leverage joints
being operatively connected with the wire that traverses the shaft
of a needle-grasping device, the distal end of a wire being coupled
with the jaw assembly. When said finger rings of the handle mechanism
are pulled apart, a leverage joints are co-jointly pulled in opposing
directions, thereby relaxing the pull on the wire. The relaxation
of the wire causes said jaws to open. When the finger rings of the
handle mechanism are approximated together thereby approximating
a leverage-joints, a strong pull is created and applied onto the
wire, causing the jaws to close tightly, thereby enabling a firm
grasp of the suture needle.
[0024] The delivery tube or tubular member is configured to house
the needle grasping device and suture needle while being passed
through the working channel of the endoscope insertion member. In
one particular embodiment of the present invention, a collar comprises
the distal end of the delivery tube, serving to protect the working
channel of the endoscope insertion member from the sharp needle
point, while enabling its exit from the flexible shaft of a delivery
tube without piercing it. A locking mechanism may be included in
the handle mechanism in order to lock said jaws in a closed position
over the needle during the suturing operation.
[0025] An additional alternative embodiment of the present invention,
wherein the temperature control system utilizes electricity for
providing heat to the suture needle, includes an electrical source
providing electrical power, such as an electrical generator. The
electrical source is operatively connected to an electrical connector
and current is passed through said electrical connector and through
an appropriate low resistance connection that is coupled to one
or both of the high resistance metal jaws of the needle-grasping
device. This delivery of power (e.g., electrical current) to a jaw
assembly causes the jaws, and subsequently the needle that is being
grasped by said jaws to become heated, thereby transforming a needle
into its austenitic state. When the suture needle requires withdrawal
at the termination of the procedure, cold water may be injected
through the designated channel in the needle-grasping device directed
to flow over a suture needle, thus rendering it malleable for withdrawal.
[0026] Alternatively, the collar that comprises the distal end
of the delivery tube may be heated to direct heat to the needle.
In another embodiment of the present invention, a delivery tube
includes insulated low resistance wires coupled to a connector.
The wires may extend along and be imbedded in the shaft of delivery
tube. An electrical source is operably connected to an electrical
connector thereby passing electrical power through said electrical
connector and down the low resistance wires. The wires are distally
connected to a high resistance metal collar. As current is transmitted
along this embodiment, the metal collar becomes hot, thus transmitting
heat to the needle thereby causing it to assume its arcuate rigid
state. Upon the need for withdrawal, cold water is injected as described.
[0027] An associated minimally invasive surgical suturing method
utilizes the above-described endoscopic surgical suturing assembly
and comprises inserting a distal end portion of the endoscope insertion
member into a patient in order to visualize the targeted tissue
for suturing. The method further comprises inserting the suture
needle grasped by needle grasping device, a needle-grasping device
being housed inside the delivery tube, into the working channel
of the endoscope insertion member. Upon visualization of target
tissue in need of a suturing, a tubular member-containing needle
grasping device and needle is ejected from the working channel of
the endoscope, while a needle is in its malleable, martensitic state.
The suture needle is then positioned proximate the target tissue,
and heated by utilizing the temperature control system preferably
by injecting hot water, thereby transforming a needle to its arcuate,
stiffened austenitic state in preparation for the suturing operation.
Upon transformation of a needle to its suturing state, the operator
manipulates the needle through target tissue by means of the endoscopic
insertion member and needle-grasping device, thus performing the
suturing operation. Upon completion, state of the art endoscopic
scissors are utilized to sever the suture thread. Thereafter, cold
water is injected through the channel in the delivery tube or the
needle grasping device, thereby transforming a needle to its malleable,
martensitic state in preparation for withdrawal of a needle from
the patient through the working channel of a endoscope insertion
member.
[0028] These embodiments and others are described in further detail
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] A complete understanding of the present invention may be
obtained by reference to the accompanying drawings, when considered
in conjunction with the subsequent, detailed description.
[0030] FIG. 1 is a schematic perspective view of the distal end
of the endoscopic surgical assembly in accordance with the present
invention.
[0031] FIG. 2 is a schematic perspective view of an embodiment
of a suture needle.
[0032] FIG. 3 is a schematic perspective view depicting a temperature
biased suture needle in the malleable (martensitic) state emerging
from the working channel of an endoscope.
[0033] FIG. 4 is a schematic perspective view depicting an endoscope
employing the suturing assembly approaching the tissue targeted
to be sutured.
[0034] FIG. 5 is a schematic perspective view depicting a curved
suture needle in its stiff (austenitic) state being held by the
needle-grasping device just prior to introduction into the targeted
tissue.
[0035] FIG. 6 is a schematic perspective view depicting the curved
suture needle in its stiff (austenitic) state being maneuvered by
the endoscope to enter the targeted tissue.
[0036] FIG. 7 is a schematic perspective view depicting the curved
suture needle in its stiff (austenitic) state emerging from the
tissue and being re-grasped by the needle-grasping device.
[0037] FIG. 8 is a schematic perspective view of the suture needle
in its malleable (martensitic) phase being pulled back into the
working channel of the endoscope after completing one stitch of
the suturing operation.
[0038] FIG. 9 is a schematic perspective view of a suture needle
depicting the needle shaft configured in a triangular "cutting"
shape, and the needle's proximal end shaped with ridges.
[0039] FIG. 9A is a schematic perspective end view depicting a
needle-grasping device holding a needle.
[0040] FIG. 9B is a schematic perspective end view depicting yet
another needle grasping device holding a needle.
[0041] FIG. 9C is a further schematic perspective end view depicting
a needle-grasping device holding a needle.
[0042] FIG. 10 is a schematic perspective view of the distal end
of the delivery tube and needle-grasping device, depicting a fluid
port built into the wall of the delivery tube.
[0043] FIG. 11 is a schematic perspective view of one embodiment
of the present invention assembly depicting the proximal end of
a needle-grasping device with an electrical temperature control
system.
[0044] FIG. 12 is a schematic perspective view of one embodiment
of the present invention assembly depicting perspective view of
the needle grasping device configured injection of fluid onto the
temperature biased suture needle.
[0045] FIG. 13 is a schematic perspective view of the needle grasping
device jaw assembly configured with a ridged surface disposed on
the inner aspect of each jaw.
[0046] FIG. 13A is a further schematic perspective view of the
needle grasping device jaw assembly configured with a ridged surface
disposed on the inner aspect of each jaw.
[0047] FIG. 14 is a schematic perspective view of the present invention
depicting a fluid channel configured into the shaft of a needle-grasping
device.
[0048] FIG. 15 is a schematic perspective view of another embodiment
of the invention depicting the needle-grasping device coupled to
an electrical source.
[0049] FIG. 16 is a schematic perspective view of yet another embodiment
of the invention depicting the needle-grasping device with low electrical
resistance conductive wires imbedded along its shaft.
[0050] FIG. 17 is a schematic view of an embodiment of the needle
grasping device handle assembly in the open configuration in accordance
with the present invention.
[0051] FIG. 18 is a schematic view of an embodiment of the needle
grasping device jaw assembly in the open configuration in accordance
with the present invention.
[0052] FIG. 19 is a schematic view of an embodiment of the needle
grasping device handle assembly in the closed configuration in accordance
with the present invention.
[0053] FIG. 20 is a schematic view of an embodiment of the needle
grasping device jaw assembly in the closed configuration in accordance
with the present invention.
[0054] FIG. 21 is a schematic side view of an embodiment of a grasping
jaw.
[0055] FIG. 22 is a perspective view of the jaw in FIG. 21.
[0056] FIG. 23 is a sectional side view of the jaw in FIG. 21.
[0057] For purposes of clarity and brevity, like elements and components
will bear the same designations and numbering throughout the figures.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0058] As illustrated in FIG. 1 an endoscopic surgery system or
surgical assembly comprises a temperature biased suture needle 10
a needle-grasping device 18 and an elongated catheter or other
delivery tube or tubular member 12 shown emerging from working
channel 14 of an endoscope insertion member 15. Delivery tube or
tubular member 12 is configured for insertion into the working channel
14 of endoscope insertion member 15. Needle grasping device 18 includes
a flexible or rigid elongated shaft, a handle mechanism and a jaw
assembly with jaws, and is movable within delivery tube 12 and is
configured for grasping and manipulating suture needle 10. Suture
needle 10 is shown in a straight malleable (martensitic) state 11
in dashed lines, and in a stiff, hardened, austenitic state 13.
Suture needle 10 is in its malleable state 11 for passage through
or manipulation inside working channel 14 of endoscope insertion
member 15 and in its hardened arcuate shape for suturing tissue.
Suture needle 10 illustrated in FIG. 1 is a temperature biased suture
needle, whereby in one particular embodiment it is made of a nickel
titanium (NiTi) alloy such as Nitinol. In the embodiment of a needle
in accordance with the present invention, the Nitinol alloy selected
for the needle 10 takes on a desired shape (arcuate) and stiffness
appropriate for suturing when heated to a certain temperature, and
becomes malleable when cooled below a specific temperature.
[0059] The term Shape Memory Alloys (SMA) is applied to that group
of metallic materials that demonstrate the ability to return to
some previously defined shape or size when subjected to a certain
strain. Although a relatively wide variety of alloys are know to
exhibit the shape memory effect, it is preferable, in accordance
with the principles of the present invention to use a specific shape
memory alloy that can return to a previously defined shape when
subjected to the appropriate thermal procedure. This material can
be plastically deformed at some relatively low temperature, while
upon exposure to a higher temperature will return to its predetermined
shape prior to the deformation. When such a temperature biased SMA
is subjected to temperatures below its transformation temperature,
it has very low yield strength and can be deformed quite easily
into any new shape. However, when the material is heated above its
transformation temperature it undergoes a change in crystal structure
that causes it to return to its original shape.
[0060] The mechanical properties of temperature biased SMAs vary
greatly over the temperature range spanning their transformation.
The martensite (malleable low temperature phase) is easily deformed
to several percent strain at quite a low stress, whereas the austenite
(stiff high temperature phase) has much higher yield and flow stresses.
Upon heating, the metal remembers its unstrained shape and reverts
to it as the material transformed to austenite.
[0061] The basis of the nickel-titanium system of alloy is the
binary, equiatomic intermetallic compound of NiTi. The intermetallic
compound is extraordinary because it has a moderate solubility range
for excess nickel or titanium, as well as most other metallic elements,
and it also exhibits ductility comparable to most ordinary alloys.
This solubility allows alloying with many of the elements to modify
the temperature transformation properties of the system. Excess
nickel, in amounts up to about 1%, is the most common alloying addition.
Excess nickel strongly depresses the transformation temperature
and increases the yield strength.
[0062] In accordance with the present invention, the needle of
the invention is made of a shape memory alloy of nickel and titanium.
The needle has a special ratio of Ni to Ti, whereby it assumes a
malleable, or martensitic, state when chilled and a rigid, or austenitic,
state when heated. In one embodiment, the Ni to Ti ratio is such
that the transition temperature from martensitic (malleable) to
austenitic (rigid) is between 30.degree. C. (.+-.3) and 39.degree.
C. (.+-.3.degree.). In a more specific embodiment, the Ni to Ti
ratio is such that the austenite (rigid) start temperature (A.sub.s)
is in the range of 30.degree. C. and its austenite (rigid) finish
temperature (A.sub.f) is in the range of 39.degree. C. In another
embodiment, the needle assumes its austenitic (rigid) state at a
temperature proximate body temperature. In still another embodiment,
the needle assumes its austenitic (rigid) state at a temperature
above body temperature.
[0063] Delivery tube 12 is shown in FIG. 1 with metal collar 16
at its distal end. Collar 16 is configured to protect the suture
needle tip during insertion of the suturing assembly through the
endoscope working channel. Metal collar 16 may also be used to transmit
heat to suture needle 10 thereby activating the austenitic arcuate
(curved) form of a suture needle 10. As discussed in detail below,
collar 16 may be coupled to a temperature control system that may
include a standard electrosurgical generator. When a generator is
coupled with the suturing assembly and activated, an electrical
current would be transmitted to collar 16 heating it, and thereby
transmitting a heat to suture needle 10. Delivery tube 12 might
also contain one or more hollow lumens or channels, at least part
way along the wall of the tubular member and configured for directing
fluid from a port located in or near the proximal handle assembly
onto to suture needle 10. Needle grasping device 18 is used to guide
suture needle 10 out of delivery tube 12 and may preferably also
be used as a source of heat for suture needle 10 to activate the
shape memory. As such, needle grasping device 18 may be coupled
to the electric temperature control system and/or have one or more
hollow lumens or channels longitudinally along its shaft or in its
shaft proximally coupled to a port in or near the handle assembly
of needle grasping device 18 and used as discussed further herein.
[0064] FIG. 2 is a schematic perspective representation of suture
needle 10 in its curved austenitic state, coupled with a suitable
suture 17. Suture needle 10 in one embodiment, is made from a temperature
biased shape memory metal, for example, Nitinol, and is configured
to include a sharp distal tip 21 for piercing tissue. In this preferred
embodiment of the present invention, Needle 10 is depicted to have
a shaped shaft with a generally triangularly shaped cross-section
with sharpened cutting angles for easy passage through tissue. The
proximal end 20 of suture needle 10 is securely attached to an appropriate
length of suture thread 17 such as biocompatible glue, for example.
[0065] FIGS. 3-8 are schematic views of an endoscope employing
the endoscopic surgical assembly of FIG. 1 showing successive steps
in a suturing operation pursuant to the invention. FIG. 3 is a schematic
perspective view of suture needle 10 delivery tube 12 with metal
collar 16 emerging from the working channel 14 of a multi-channel
endoscope insertion member 15. Targeted tissue 30 to be sutured
is shown as well. Suture needle 10 is in a generally straight configuration
and is in its malleable martensitic phase at a temperature below
the heated state as it is ejected from the distal end of the delivery
tube 12 by needle grasping device 18 housed inside delivery tube
12.
[0066] FIG. 4 is a perspective view of suture needle 10 needle
grasping device 18 and metal collar 16 emerging from one working
channel of endoscope insertion member 15. In this figure needle-grasping
device 18 is holding suture needle 10 coupled with suture 17. The
needle is still in the malleable martensitic state because heat
has not yet been applied to suture needle 10 to activate its shape
memory.
[0067] FIG. 5 is a schematic perspective view of needle grasping
device 18 holding curved suture needle 10. Needle 10 is in its rigid,
curved, austenitic state after heat has been applied to it in order
to activate its shape memory. Suture 17 and targeted tissue 30 to
be sutured are shown as well.
[0068] FIG. 6 is a schematic perspective view of needle grasping
device 18 emerging from delivery tube 12 with metal collar 13 a
suturing assembly being employed by endoscope insertion member 15.
Needle grasping device 18 has a firm hold on curved suture needle
10 a needle being guided into target tissue 30 with the aid of
endoscope insertion member 15 and needle-grasping device 18. Suture
17 is securely attached to proximal end of suture needle 10.
[0069] FIG. 7 is a schematic perspective view of curved suture
needle 10 emerging from targeted tissue 30 and being captured by
needle grasping device 18. Suture 17 is pulled through targeted
tissue 30 as suture needle 10 is passed, thus forming a loop of
suture 17 which may be tied to approximate and secure tissue in
the desired position.
[0070] FIG. 8 is a schematic perspective view of the distal end
of suture needle 10 being pulled back into delivery tube 12 while
a suture line cutter 32 is passed through another working channel
14 of the endoscope insertion member 15. Suture cutter or scissors
32 is used to sever suture needle 10 from suture 17 after a knot
has been tied to secure tissue in preferred position. Upon grasping
of suture needle's distal tip by needle grasping device 18 cooling
of suture needle 10 may take place by injection of cold water through
a specially allocated channel in needle grasping device 18 or delivery
tube 12 to be shown further below. This cooling process transforms
suture needle 10 into its malleable or martensitic state, thus facilitating
its removal through the working channel 14 of endoscope insertion
member 15 along with excess suture 17.
[0071] FIG. 9 is a schematic perspective view of an alternative
embodiment of suture needle 10 wherein the shaft of suture needle
10a has a cross-section with a generally triangular shape, with
the three angles of the triangle being sharply formed, configured
for cutting and easy passage through the tissue. The proximal end
22 of needle 10a is flattened with a rectangular cross section,
a flattened portion's surfaces configured with a series of ridges
23 a ridges corresponding to similar ridges located in the inner
surface of the jaw assembly of needle grasping device 18 (FIG.
10) to provide a better hold of the needle by a jaws. Most particularly,
the hold that is desired is one that would not allow for suture
needle 10a to rotate on its own axis during the process of suturing
tissue.
[0072] FIGS. 9A, 9B, and 9C illustrate alternative means and embodiments
for grasping and manipulating needle 10a with needle grasping device
18. Alternatively, the proximal end of suturing needle 1 may be
constructed in a triangular, rectangular or circular cross section.
The cross-sectional configuration of a portion of the needle may
be circular, rectangular, or triangular.
[0073] FIG. 10 represents a perspective view of one embodiment
of the present invention wherein heated or cooled fluid 37 is used
to transform suturing needle 10 from an austenitic to a martensitic
state, and vice versa. A fluid port 34 is coupled to one or more
channels disposed or fashioned longitudinally along the delivery
tube 12 for directing warm fluid through a channel in tube 12 and
out its distal end for the purpose of bathing a needle and transforming
it into its hardened arcuate state. Delivery tube 12 might include
a separate channel 35 for the fluid 37 or the fluid may traverse
through the passage or channel, which extends through the delivery
tube 12 in which the needle-grasping device 18 is positioned. When
suture needle 10 requires withdrawal through working channel 14
of endoscope insertion member 15 fluid port 34 is utilized in order
to direct cooled or cold fluid to bathe suture needle 10 thereby
transforming it into its malleable state. Fluid port 34 may be coupled
with a temperature control system 36 that includes supplies of hot
38 and cold 39 fluids, or fluids of varying temperature. A syringe,
for example may be used for the purpose of injecting fluid to port
34.
[0074] FIG. 11 represents a schematic perspective view of an alternative
embodiment showing the port 34 located proximate the handle 26.
Port 34 is operably coupled with delivery tube 12 and with a temperature
control system that may include heated or cooled fluid (FIG. 10).
Warm fluid may be injected into injection port 34 and directed along
delivery tube 12 to exit at fluid port 38 at the distal end of the
tube 12 bathing the suture needle and thereby causing its transformation
into the hardened state. Alternatively, when the needle requires
withdrawal, cold water is injected rendering suture needle 10 malleable.
[0075] FIGS. 12 and 14 illustrate a schematic perspective representation
of another embodiment of the invention wherein the fluid is directed
through the needle-grasping device. Referring to FIG. 14 the needle-grasping
device includes a fluid channel 40 which extends along at least
a portion of the length of the needle-grasping device and is coupled
with injection port 34 (FIG. 12). The fluid channel 40 terminates
in an outlet 42 proximate jaw assembly 24 of the needle holding
device. In this preferred embodiment, fluid channel 40 conducts
heated or cooled fluid 37 injected into injection port 34 to fluid
outlet 42 at the distal end of needle grasping device 18 causing
the desired deformation and shaping of suture needle 10 in accordance
with the invention.
[0076] FIGS. 13 and 13A are perspective views of needle grasping
device jaws 24 with ridges 25 placed onto the inner surfaces of
said jaws. Ridges may be cut into various patterns with embodiments
having vertical or horizontal ridges down the inside of both jaws
(FIG. 13A). Another embodiment may be configured with diagonal ridges,
while another, with ridges cut into a checkerboard pattern (FIG.
13) or diamond pattern.
[0077] FIGS. 15 and 16 illustrate additional alternative embodiments
of the invention wherein the temperature control system is electric
in nature and utilizes electricity for providing heat to the suture
needle 10. The embodiment depicted in FIG. 15 illustrates a temperature
control system 44 that includes an electrical source 48 providing
electrical power, such as an electrical generator. Electrical source
48 is operatively connected to an electrical connector 46 and electric
current is passed through electrical connector 46 and through an
appropriate low resistance connection that is coupled to one or
both of the high resistance metal jaws of the needle grasping device
18. This delivery of power (e.g., electrical current) to jaw assembly
24 causes the jaws, and subsequently the needle that is being grasped
by said jaws to become heated, thereby transforming needle 10 into
its rigid state. When suture needle 10 requires withdrawal at the
termination of the procedure, cold water may be directed toward
the distal end of delivery tube 12 flowing over suture needle 10
rendering suture needle 10 malleable for withdrawal as discussed
above. A locking mechanism may be included in the handle mechanism
in order to lock jaws 24 in a closed position over the needle during
the suturing operation. The system might include a lock button 48
for this purpose (FIG. 15). Alternatively, collar 16 of delivery
tube 12 may be heated to direct heat to the needle. FIG. 16 illustrates
an embodiment that includes insulated low resistance wires 50 coupled
to connector 46. The wires may extend along and be imbedded in the
shaft of tubular number or delivery tube 12. An electrical source
48 may be operably connected to electrical connector 46 thereby
passing electrical power through electrical connector 46 and down
the low resistance wires 50. The wires 50 are distally connected
to high resistance metal collar 16. As current is transmitted along
this embodiment, metal collar 16 becomes hot, transmitting heat
to needle 10 and causing it to assume its arcuate rigid state.
Upon the need for withdrawal, cold water is injected as described
above.
[0078] FIG. 17 illustrates another embodiment of the needle-grasping
device in an open configuration. Push-pull wire 62 traverses through
shaft 68 or is incorporated into the shaft and is operably connected
to jaw mechanism 66 distally and leverage-joints 70 proximally.
When opposing scissor finger rings or handles 64A and 64B of the
device are pulled apart or separated, leverage-joints 70 are co-jointly
pulled in opposing directions or separated, thereby relaxing the
pull on wire 62 and moving the wire in a distal direction toward
jaws 74A, 74B causing jaws 74A and 74B to open. FIG. 18 is a detailed
illustration of jaw mechanism 66 depicting jaws 74A and 74B in an
open position. Flush port 60 (FIG. 17) is designed for introduction
of hot or cold water, which flows through a separate channel in
shaft 68 (Illustrated in FIG. 20) and bathes the temperature biased
suture needle in jaw mechanism 66. The needle-grasping device includes
a ratchet locking structure 65 to hold the scissor finger rings
together tightly to grasp the needle.
[0079] FIG. 19 illustrates the preferred embodiment of the needle
grasper in a closed configuration. Scissor finger rings 64A, 64B
are approximated, causing leverage-joints 70 to be brought together
or approximated, thereby applying a strong pull on wire 62. As a
result, jaws 74A and 74B are approximated together tightly, allowing
for a firm grasp of the suture needle. The ratchet locking structure
65 is shown locked to hold the jaws together. FIG. 20 is a detailed
schematic representation illustrating tightly closed jaws 74A and
74B. Flush channel 78 that communicates with flush-port 60 is illustrated
in FIG. 20.
[0080] FIGS. 21 and 22 depict a detailed drawing of jaws 74A and
74B. The proximal aspect of the jaws, namely leg 80 is operatively
coupled to wire 62 allowing for secure closure of the jaws. The
jaws 74A, 74B each include a leg 80 and a pivot opening 84 to receive
a pin or other pivot element for pivoting. The legs 80 are at an
angle to the toothed portion of the jaws. As the legs are spread
apart, the jaws spread apart (FIG. 18). Scissor linkages 81 are
pivotally coupled to each leg 80 at respective pivot points or pivot
pins at one end. The other ends of the scissor linkages 81 are appropriately
coupled at another pivot point 83 to cable 62. When scissor ring
fingers 64A, 64B are brought together, the cable 62 slides in a
distal direction and cable 62 is pushed or relaxed (FIG. 17). The
distance between the pivot points 83 84 is reduced and the jaws
open and when cable 62 is pulled or tensioned (FIG. 19), the jaws
close. FIG. 22 depicts one construction of the jaws. Their broader
proximal and narrower distal ends adds leverage to the grasping
force of the needle shaft. Teeth 82 situated on the inner aspect
of the jaws, depicted in even greater detail in FIG. 23 are constructed
so as to correspond with the ridges on the needle's proximal end,
thereby providing for a secure grip of a needle.
[0081] While the present invention has been illustrated by a description
of various embodiments and while these embodiments have been described
in considerable detail, it is not the intention of the applicant
to restrict or in any way limit the scope of the appended claims
to such detail. Additional advantages and modifications will readily
appear to those skilled in the art. The invention in its broader
aspects is therefore not limited to the specific details, representative
apparatus and method, and illustrative examples shown and described.
Accordingly, departures may be made from such details without departing
from the spirit or scope of applicant's general inventive concept.
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