U.S. patent application number 13/442020 was filed with the patent office on 2013-10-10 for surgical instrument with nerve detection feature.
The applicant listed for this patent is William D. Dannaher, Timothy G. Dietz, Donna L. Korvick, Ashvani K. Madan, Amy L. Marcotte. Invention is credited to William D. Dannaher, Timothy G. Dietz, Donna L. Korvick, Ashvani K. Madan, Amy L. Marcotte.
Application Number | 20130267874 13/442020 |
Document ID | / |
Family ID | 48096340 |
Filed Date | 2013-10-10 |
United States Patent
Application |
20130267874 |
Kind Code |
A1 |
Marcotte; Amy L. ; et
al. |
October 10, 2013 |
SURGICAL INSTRUMENT WITH NERVE DETECTION FEATURE
Abstract
A surgical apparatus comprises an instrument body, an end
effector, and a control module. The end effector is in
communication with the handle assembly. The end effector is
operable for use in a surgical procedure. The control module is in
communication with the end effector. The end effector with the
control module is able to deliver surgical energy as well as nerve
excitation energy to a surgical site. A surgeon may detect
stimulation of nervous tissue by visually observing the tissue
twitch, and may adjust surgical technique accordingly. A sensor may
be used to detect excitation of nervous tissue based on excitation
caused by the nerve excitation energy.
Inventors: |
Marcotte; Amy L.; (Mason,
OH) ; Dietz; Timothy G.; (Terrace Park, OH) ;
Korvick; Donna L.; (Maineville, OH) ; Madan; Ashvani
K.; (Mason, OH) ; Dannaher; William D.;
(Suzhou, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Marcotte; Amy L.
Dietz; Timothy G.
Korvick; Donna L.
Madan; Ashvani K.
Dannaher; William D. |
Mason
Terrace Park
Maineville
Mason
Suzhou |
OH
OH
OH
OH |
US
US
US
US
CN |
|
|
Family ID: |
48096340 |
Appl. No.: |
13/442020 |
Filed: |
April 9, 2012 |
Current U.S.
Class: |
601/2 ;
606/41 |
Current CPC
Class: |
A61B 2017/320093
20170801; A61B 2017/320094 20170801; A61B 2017/320095 20170801;
A61B 2017/320097 20170801; A61B 5/4893 20130101; A61B 18/1445
20130101; A61B 2017/00026 20130101; A61B 2018/00791 20130101; A61B
2017/00106 20130101 |
Class at
Publication: |
601/2 ;
606/41 |
International
Class: |
A61N 7/00 20060101
A61N007/00; A61B 18/18 20060101 A61B018/18 |
Claims
1. An apparatus comprising: (a) an instrument body; (b) an end
effector in communication with the instrument body, wherein the end
effector is operable to perform a surgical operation at a surgical
site, wherein the end effector is further operable to deliver nerve
excitation energy to tissue at the surgical site; and (c) a control
module in communication with the end effector, wherein the control
module is operable to drive the end effector to deliver surgical
energy to the surgical site, wherein the control module is further
operable to drive the end effector to deliver nerve excitation
energy to the surgical site.
2. The apparatus of claim 1, further comprising a sensor in
communication with the control module, wherein the sensor is
configured to detect excitation of nervous tissue based on
excitation caused by the nerve excitation energy.
3. The apparatus of claim 2, wherein the sensor is positioned on a
distal end of the end effector.
4. The apparatus of claim 2, wherein the sensor comprises an
impedance sensor.
5. The apparatus of claim 2, wherein the sensor comprises a
plurality of current sensing electrodes.
6. The apparatus of claim 2, wherein the end effector comprises a
blade and a clamp arm.
7. The apparatus of claim 6, wherein the sensor is positioned on
the clamp arm.
8. The apparatus of claim 6, wherein the blade is configured to
deliver energy operable to excite nervous tissue.
9. The apparatus of claim 2, further comprising an indicator in
communication with the sensor, wherein the indicator is configured
convey whether the sensor detects a biological response to the
nerve excitation energy.
10. The apparatus of claim 9, wherein the indicator comprises a
visual indicator.
11. The apparatus of claim 9, wherein the indicator comprises an
audio indicator.
12. The apparatus of claim 1, further comprising a transducer
configured to convert electrical power into ultrasonic vibration
energy, wherein the surgical energy comprises the ultrasonic
vibration energy.
13. The apparatus of claim 12, wherein the control module is
operable to drive the transducer with pulses of electrical power to
create the ultrasonic vibration energy.
14. The apparatus of claim 13, wherein the control module is
further operable to deliver the nerve excitation energy between the
pulses of electrical power used to create the ultrasonic vibration
energy.
15. The apparatus of claim 1, wherein the nerve excitation energy
comprises pulsatile electrical current.
16. An apparatus comprising: (a) an instrument body; (b) an end
effector in communication with the instrument body, wherein the end
effector comprises an ultrasonic blade operable to deliver
ultrasonic energy to tissue at a surgical site; and (c) a control
module in communication with the end effector, wherein the control
module is operable to selectively activate the ultrasonic blade to
deliver ultrasonic energy to tissue at a surgical site, wherein the
control module is further operable to activate the end effector to
deliver nerve excitation energy through the end effector to tissue
at the surgical site.
17. The apparatus of claim 16, wherein the end effector further
comprises a clamp arm operable to selectively pivot toward and away
from the ultrasonic blade.
18. The apparatus of claim 17, wherein the control module is
operable to deliver nerve excitation energy through the clamp arm
to tissue at the surgical site.
19. The apparatus of claim 16, wherein the nerve excitation energy
comprises AC electrical current.
20. A method of detecting nervous tissue during a surgical
procedure with a surgical instrument having an end effector, the
method comprising: (a) positioning the end effector at a surgical
site in the body of a patient; (b) activating the end effector to
perform a surgical function on tissue at the surgical site; (c)
activating the end effector to excite nervous tissue at or near the
surgical site; and (d) detecting the excitation of nervous tissue.
Description
BACKGROUND
[0001] In some settings, endoscopic surgical instruments may be
preferred over traditional open surgical devices since a smaller
incision may reduce the post-operative recovery time and
complications. Consequently, some endoscopic surgical instruments
may be suitable for placement of a distal end effector at a desired
surgical site through a cannula of a trocar. These distal end
effectors may engage tissue in a number of ways to achieve a
diagnostic or therapeutic effect (e.g., endocutter, grasper,
cutter, stapler, clip applier, access device, drug/gene therapy
delivery device, and energy delivery device using ultrasound, RF,
laser, etc.). Endoscopic surgical instruments may include a shaft
between the end effector and a handle portion, which is manipulated
by the clinician. Such a shaft may enable insertion to a desired
depth and rotation about the longitudinal axis of the shaft,
thereby facilitating positioning of the end effector within the
patient.
[0002] Examples of endoscopic surgical instruments include those
disclosed in U.S. Pat. Pub. No. 2006/0079874, entitled "Tissue Pad
for Use with an Ultrasonic Surgical Instrument," published Apr. 13,
2006, the disclosure of which is incorporated by reference herein;
U.S. Pat. Pub. No. 2007/0191713, entitled "Ultrasonic Device for
Cutting and Coagulating," published Aug. 16, 2007, the disclosure
of which is incorporated by reference herein; U.S. Pat. Pub. No.
2007/0282333, entitled "Ultrasonic Waveguide and Blade," published
Dec. 6, 2007, the disclosure of which is incorporated by reference
herein; U.S. Pat. Pub. No. 2008/0200940, entitled "Ultrasonic
Device for Cutting and Coagulating," published Aug. 21, 2008, the
disclosure of which is incorporated by reference herein; U.S. Pat.
Pub. No. 2011/0015660, entitled "Rotating Transducer Mount for
Ultrasonic Surgical Instruments," published Jan. 20, 2011, the
disclosure of which is incorporated by reference herein; U.S. Pat.
No. 6,500,176, entitled "Electrosurgical Systems and Techniques for
Sealing Tissue," issued Dec. 31, 2002, the disclosure of which is
incorporated by reference herein; and U.S. Pat. Pub. No.
2011/0087218, entitled "Surgical Instrument Comprising First and
Second Drive Systems Actuatable by a Common Trigger Mechanism,"
published Apr. 14, 2011, the disclosure of which is incorporated by
reference herein. Additionally, such surgical tools may include a
cordless transducer such as that disclosed in U.S. Pat. Pub. No.
2009/0143797, entitled "Cordless Hand-held Ultrasonic Cautery
Cutting Device," published Jun. 4, 2009, the disclosure of which is
incorporated by reference herein. In addition, the surgical
instruments may be used, or adapted for use, in robotic-assisted
surgery settings such as that disclosed in U.S. Pat. No. 6,783,524,
entitled "Robotic Surgical Tool with Ultrasound Cauterizing and
Cutting Instrument," issued Aug. 31, 2004, the disclosure of which
is incorporated by reference herein.
[0003] While a variety of surgical instruments have been made and
used, it is believed that no one prior to the inventor(s) has made
or used an invention as described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] While the specification concludes with claims which
particularly point out and distinctly claim the invention, it is
believed the present invention will be better understood from the
following description of certain examples taken in conjunction with
the accompanying drawings, in which like reference numerals
identify the same elements and in which:
[0005] FIG. 1 depicts a block diagram view of an exemplary surgical
instrument;
[0006] FIG. 2 depicts a perspective view of an exemplary ultrasonic
surgical instrument;
[0007] FIG. 3 depicts a block diagram view of an exemplary surgical
instrument with a sensor;
[0008] FIG. 4 depicts a side view of an end effector of an
exemplary surgical instrument with a sensor in accordance with the
block diagram of FIG. 3;
[0009] FIG. 5A depicts a side view of the end effector of FIG. 4
approaching tissue;
[0010] FIG. 5B depicts a side view of the end effector of FIG. 4
clamped on tissue and exciting nervous tissue; and
[0011] FIG. 6 depicts a flowchart view of an exemplary method of
using a surgical instrument having the end effector of FIG. 4.
[0012] The drawings are not intended to be limiting in any way, and
it is contemplated that various embodiments of the invention may be
carried out in a variety of other ways, including those not
necessarily depicted in the drawings. The accompanying drawings
incorporated in and forming a part of the specification illustrate
several aspects of the present invention, and together with the
description serve to explain the principles of the invention; it
being understood, however, that this invention is not limited to
the precise arrangements shown.
DETAILED DESCRIPTION
[0013] The following description of certain examples of the
invention should not be used to limit the scope of the present
invention. Other examples, features, aspects, embodiments, and
advantages of the invention will become apparent to those skilled
in the art from the following description, which is by way of
illustration, one of the best modes contemplated for carrying out
the invention. As will be realized, the invention is capable of
other different and obvious aspects, all without departing from the
invention. For example, while various. Accordingly, the drawings
and descriptions should be regarded as illustrative in nature and
not restrictive.
[0014] It is further understood that any one or more of the
teachings, expressions, embodiments, examples, etc. described
herein may be combined with any one or more of the other teachings,
expressions, embodiments, examples, etc. that are described herein.
The following-described teachings, expressions, embodiments,
examples, etc. should therefore not be viewed in isolation relative
to each other. Various suitable ways in which the teachings herein
may be combined will be readily apparent to those of ordinary skill
in the art in view of the teachings herein. Such modifications and
variations are intended to be included within the scope of the
claims.
[0015] I. Overview of Exemplary Surgical Instrument
[0016] FIG. 1 shows components of an exemplary medical device
and/or surgical instrument (10) in diagrammatic block form. As
shown, medical device (10) comprises a control module (12), a power
source (14), and an end effector (16). Merely exemplary power
sources (14) may include NiMH batteries, Li-ion batteries (e.g.,
prismatic cell type lithium ion batteries, etc.), Ni-Cad batteries,
or any other type of power source as may be apparent to one of
ordinary skill in the art in light of the teachings herein. Control
module (12) may comprise a microprocessor, an application specific
integrated circuit (ASIC), memory, a printed circuit board (PCB), a
storage device (such as a solid state drive or hard disk),
firmware, software, or any other suitable control module components
as will be apparent to one of ordinary skill in the art in light of
the teachings herein. Control module (12) and power source (14) are
coupled by an electrical connection (22), such as a cable and/or
traces in a circuit board, etc., to transfer power from power
source (14) to control module (12). Alternatively, power source
(14) may be selectively coupled to control module (12). This allows
power source (14) to be detached and removed from medical device
(10), which may further allow power source (14) to be readily
recharged or reclaimed for resterilization and reuse. In addition
or in the alternative, control module (12) may be removed for
servicing, testing, replacement, or any other purpose as will be
apparent to one of ordinary skill in the art in view of the
teachings herein. Control module (12) may also be operable to
provide pulsing energy through use of power source (14) as will be
discussed further below.
[0017] End effector (16) is coupled to control module (12) by
another electrical connection (22). End effector (16) is configured
to perform a desired function of medical device (10). By way of
example only, such function may include cauterizing tissue,
ablating tissue, severing tissue, ultrasonically vibrating,
stapling tissue, or any other desired task for medical device (10).
End effector (16) may thus include an active feature such as an
ultrasonic blade, a pair of clamping jaws, a sharp knife, a staple
driving assembly, a monopolar RF electrode, a pair of bipolar RF
electrodes, a thermal heating element, and/or various other
components. End effector (16) may also be removable from medical
device (10) for servicing, testing, replacement, or any other
purpose as will be apparent to one of ordinary skill in the art in
view of the teachings herein. In some versions, end effector (16)
is modular such that medical device (10) may be used with different
kinds of end effectors (e.g., as taught in U.S. Provisional
Application Ser. No. 61/410,603, etc.). Various other
configurations of end effector (16) may be provided for a variety
of different functions depending upon the purpose of medical device
(10) as will be apparent to those of ordinary skill in the art in
view of the teachings herein. Similarly, other types of components
of a medical device (10) that may receive power from power source
(14) will be apparent to those of ordinary skill in the art in view
of the teachings herein.
[0018] Medical device (10) of the present example includes a
trigger (18) and a sensor (20), though it should be understood that
such components are merely optional. Trigger (18) is coupled to
control module (12) and power source (14) by electrical connection
(22). Trigger (18) may be configured to selectively provide power
from power source (14) to end effector (16) (and/or to some other
component of medical device (10)) to activate medical device (10)
when performing a procedure. Sensor (20) is also coupled to control
module (12) by an electrical connection (22) and may be configured
to provide a variety of information to control module (12) during a
procedure. By way of example only, such configurations may include
sensing a temperature at end effector (16) or determining the
oscillation rate of end effector (16). Data from sensor (20) may be
processed by control module (12) to effect the delivery of power to
end effector (16) (e.g., in a feedback loop, etc.). Various other
configurations of sensor (20) may be provided depending upon the
purpose of medical device (10) as will be apparent to those of
ordinary skill in the art in view of the teachings herein. Of
course, as with other components described herein, medical device
(10) may have more than one sensor (20), or sensor (20) may simply
be omitted if desired. Further detail regarding sensor (20) and
variations thereof will be discussed below.
[0019] II. Exemplary Ultrasonic Surgical Instrument
[0020] FIG. 2 shows a surgical system (11), which includes an
exemplary ultrasonic version (50) of instrument (10) described
above. When ultrasonic components of instrument (50) are inactive,
tissue can be readily gripped and manipulated, as desired, without
tissue cutting. When the ultrasonic components are activated,
instrument (50) permits tissue to be gripped by end effector (80)
for coupling with the ultrasonic energy to effect tissue
coagulation, with application of increased pressure efficiently
effecting tissue cutting and coagulation. If desired, ultrasonic
energy can be applied to tissue without use of the clamping
mechanism of end effector (80) by appropriate manipulation of the
ultrasonic blade (82).
[0021] By way of example only, surgical system (11) may be
constructed and/or operable in accordance with any suitable
teachings or combinations of teachings from any of the following:
U.S. Pat. No. 7,738,971 entitled "Post-Sterilization Programming of
Surgical Instruments," issued Jun. 15, 2010, the disclosure of
which is incorporated by reference herein; U.S. Pub. No.
2006/0079874 entitled "Tissue Pad for Use with an Ultrasonic
Surgical Instrument," published Apr. 13, 2006, the disclosure of
which is incorporated by reference herein; U.S. Pub. No.
2007/0191713 entitled "Ultrasonic Device for Cutting and
Coagulating," published Aug. 16, 2007, the disclosure of which is
incorporated by reference herein; U.S. Pub. No. 2007/0282333
entitled "Ultrasonic Waveguide and Blade," published Dec. 6, 2007,
the disclosure of which is incorporated by reference herein; U.S.
Pub. No. 2008/0200940 entitled "Ultrasonic Device for Cutting and
Coagulating," published Aug. 21, 2008, the disclosure of which is
incorporated by reference herein; U.S. Pat. Pub. No. 2009/0143797,
entitled "Cordless Hand-held Ultrasonic Cautery Cutting Device,"
published Jun. 4, 2009, the disclosure of which is incorporated by
reference herein; U.S. Pub. No. 2009/0209990 entitled "Motorized
Surgical Cutting and Fastening Instrument Having Handle Based Power
Source," published Aug. 20, 2009, the disclosure of which is
incorporated by reference herein; U.S. Pub. No. 2010/0069940
entitled "Ultrasonic Device for Fingertip Control," published Mar.
18, 2010, the disclosure of which is incorporated by reference
herein; and U.S. Pub. No. 2011/0015660, entitled "Rotating
Transducer Mount for Ultrasonic Surgical Instruments," published
Jan. 20, 2011, the disclosure of which is incorporated by reference
herein. Similarly, various ways in which medical devices may be
adapted to include a portable power source are disclosed in U.S.
Provisional Application Ser. No. 61/410,603, filed Nov. 5, 2010,
entitled "Energy-Based Surgical Instruments," the disclosure of
which is incorporated by reference herein.
[0022] Exemplary ultrasonic surgical system (11) comprises an
ultrasonic surgical instrument (50), a generator (21), and a cable
(30) operable to couple generator (21) to surgical instrument (50).
A suitable generator (21) is the GEN 300 sold by Ethicon
Endo-Surgery, Inc. of Cincinnati, Ohio. By way of example only,
generator (21) may be constructed in accordance with the teachings
of U.S. Pub. No. 2011/0087212, entitled "Surgical Generator for
Ultrasonic and Electrosurgical Devices," published Apr. 14, 2011,
the disclosure of which is incorporated by reference herein. It
should be noted that surgical instrument (50) will be described in
reference to an ultrasonic surgical instrument; however, the
technology described below may be used with a variety of surgical
instruments, including, but not limited to, endocutters, graspers,
cutters, staplers, clip appliers, access devices, drug/gene therapy
delivery devices, and energy delivery devices using ultrasound, RF,
laser, etc., and/or any combination thereof as will be apparent to
one of ordinary skill in the art in view of the teachings herein.
Moreover, while the present example will be described in reference
to a cable-connected surgical instrument (50), it should be
understood that surgical instrument (50) may be adapted for
cordless operation, such as that disclosed in U.S. Pat. Pub. No.
2009/0143797. Furthermore, surgical device (50) may also be used,
or adapted for use, in robotic-assisted surgery settings such as
that disclosed in U.S. Pat. No. 6,783,524.
[0023] Surgical instrument (50) of the present example includes a
multi-piece handle assembly (60), an elongated transmission
assembly (70), and a transducer (100). Transmission assembly (70)
is coupled to multi-piece handle assembly (60) at a proximal end of
transmission assembly (70) and extends distally from multi-piece
handle assembly (60). In the present example transmission assembly
(70) is configured to be an elongated, thin tubular assembly for
endoscopic use, but it should be understood that transmission
assembly (70) may alternatively be a short assembly, such as those
disclosed in U.S. Pat. Pub. No. 2007/0282333 and U.S. Pat. Pub. No.
2008/0200940. Transmission assembly (70) of the present example
comprises an outer sheath (72), an inner tubular actuating member
(not shown), a waveguide (not shown), and an end effector (80)
located on the distal end of transmission assembly (70). In the
present example, end effector (80) comprises a blade (82) coupled
to the waveguide, a clamp arm (84) operable to pivot at the
proximal end of transmission assembly (70), and, optionally, one or
more clamp pads (86) coupleable to clamp arm (84). It should also
be understood that clamp arm (84) and associated features may be
constructed and operable in accordance with at least some of the
teachings of U.S. Pat. No. 5,980,510, entitled "Ultrasonic Clamp
Coagulator Apparatus Having Improved Clamp Arm Pivot Mount," issued
Nov. 9, 1999, the disclosure of which is incorporated by reference
herein. It should also be understood that some versions of end
effector (80) may lack clamp arm (84). For instance, end effector
(80) may simply include blade (82). The waveguide, which is adapted
to transmit ultrasonic energy from a transducer (100) to blade
(82), may be flexible, semi-flexible, or rigid. One merely
exemplary ultrasonic transducer (100) is Model No. HP054, sold by
Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. The waveguide may
also be configured to amplify the mechanical vibrations transmitted
through the waveguide to blade (82) as is well known in the art.
The waveguide may further have features to control the gain of the
longitudinal vibration along the waveguide and features to tune the
waveguide to the resonant frequency of the system.
[0024] In the present example, the distal end of the blade (82) is
disposed near an anti-node in order to tune the acoustic assembly
to a preferred resonant frequency f.sub.o when the acoustic
assembly is not loaded by tissue. When transducer (100) is
energized, the distal end of blade (82) is configured to move
longitudinally in the range of, for example, approximately 10 to
500 microns peak-to-peak, and preferably in the range of about 20
to about 200 microns at a predetermined vibratory frequency f.sub.o
of, for example, 55.5 kHz. When transducer (100) of the present
example is activated, these mechanical oscillations are transmitted
through the waveguide to end effector (80). In the present example,
blade (82), being coupled to the waveguide, oscillates at the
ultrasonic frequency. Thus, when tissue is secured between blade
(82) and clamp arm (84), the ultrasonic oscillation of blade (82)
may simultaneously sever the tissue and denature the proteins in
adjacent tissue cells, thereby providing a coagulative effect with
relatively little thermal spread. An electrical current may also be
provided through blade (82) and clamp arm (84) to also cauterize
the tissue. While some configurations for transmission assembly
(70) and transducer (100) have been described, still other suitable
configurations for transmission assembly (70) and transducer (100)
will be apparent to one or ordinary skill in the art in view of the
teachings herein.
[0025] Multi-piece handle assembly (60) of the present example
comprises a mating housing portion (62) and a lower portion (64).
Mating housing portion (62) is configured to receive transducer
(100) at a proximal end of mating housing portion (62) and to
receive the proximal end of transmission assembly (70) at a distal
end of mating housing portion (62). An aperture is provided on the
distal end of mating housing portion (62) for insertion of various
transmission assemblies (70). A rotation knob (66) is shown in the
present example to rotate transmission assembly (70) and/or
transducer (100), but it should be understood that rotation knob
(66) is merely optional. Lower portion (64) of multi-piece handle
assembly (60) includes a trigger (68) and is configured to be
grasped by a user using a single hand. One merely exemplary
alternative configuration for lower portion (64) is depicted in
FIG. 1 of U.S. Pat. Pub. No. 2011/0015660. Toggle buttons (not
shown) may be located on a distal surface of lower portion (64) and
may be operable to activate transducer (100) at different
operational levels using generator (21). For instance, a first
toggle button may activate transducer (100) at a maximum energy
level while a second toggle button may activate transducer (100) at
a minimum, non-zero energy level. Of course, the toggle buttons may
be configured for energy levels other than a maximum and/or minimum
energy level as will be apparent to one of ordinary skill in the
art in view of the teachings herein. Moreover, the toggle buttons
may be located anywhere else on multi-piece handle assembly (60),
on transducer (100), and/or remote from surgical instrument (50),
and any number of toggle buttons may be provided. While multi-piece
handle assembly (60) has been described in reference to two
distinct portions (62, 64), it should be understood that
multi-piece handle assembly (60) may be a unitary assembly with
both portions (62, 64) combined. Multi-piece handle assembly (60)
may alternatively be divided into multiple discrete components,
such as a separate trigger portion (operable either by a user's
hand or foot) and a separate mating housing portion (62). The
trigger portion may be operable to activate transducer (100) and
may be remote from mating housing portion (62). Multi-piece handle
assembly (60) may be constructed from a durable plastic (such as
polycarbonate or a liquid crystal polymer), ceramics and/or metals
or any other suitable material as will be apparent to one of
ordinary skill in the art in view of the teachings herein. Still
other configurations for multi-piece handle assembly (60) will be
apparent to those of ordinary skill in the art in view of the
teachings herein. For instance, instrument (50) may be operated as
part of a robotic system. Other configurations for multi-piece
handle assembly (60) will also be apparent to those of ordinary
skill in the art in view of the teachings herein.
[0026] Still other suitable forms that system (11) and components
thereof may take will be apparent to those of ordinary skill in the
art in view of the teachings herein.
[0027] III. Surgical Instrument with Nerve Detection Features
[0028] It will be appreciated that in some instances, it may be
desirable to either avoid or simply have knowledge of when a
surgical instrument, such as instruments (10, 50) described above,
is near nervous tissue. In other instances, it may be desirable for
a user to interact with nervous tissue. For example, during the
surgical procedure, the user may wish to ablate a portion of
nervous tissue or use information measured from nervous tissue to
determine the whether the nervous tissue is experiencing excessive
heat, etc. Intentional nerve ablation may be performed in a
procedure on a patient's epicardium to reduce the incidence of
arrhythmia, in procedures setting a nerve block to manage chronic
pain, in aesthetic procedures to able wrinkle creating nerves, etc.
Other information related to or arising from nervous tissue may be
used or otherwise desirable, as will be apparent to one of ordinary
skill in the art in view of the teachings herein.
[0029] FIG. 3 shows one exemplary version of a surgical instrument
(400) having an end effector (412) attached to a handle assembly
(410). Handle assembly (410) is in communication with a power
source and/or generator (418). Handle assembly (410) is also in
communication with a control board (416), which, in the exemplary
version, is operable to control many of the functions related to
detecting whether end effector (412) is near nervous tissue.
Surgical instrument (400) of this example may be viewed as a
variation of instruments (10, 50) described above. It will be
appreciated that while the exemplary version shows one
layout/configuration, other potential layouts and configurations
are contemplated. For example, while control board (416) is
depicted as being located outside of handle assembly (410), other
suitable locations for control board (416) may be used as would be
apparent to one of ordinary skill in the art in view of the
teachings herein. As an alternative example, control board (416)
may be integrated into handle assembly (410), into end effector
(412), into power source (418), and/or elsewhere. Similarly, it
will be appreciated that power source (418) may have different
configurations than the exemplary version shown in FIG. 3. For
example, power source (418) may be located outside of handle
assembly (410); or be contained within or integrated with handle
assembly (410). In yet other exemplary versions, power source
(418), end effector (412), and control board (416) may be
integrated together. Other suitable configurations will be apparent
to one of ordinary skill in the art in view of the teachings
herein.
[0030] A. Exemplary Nerve Stimulus
[0031] There are numerous ways to detect the presence or proximity
of nervous tissue, particularly by stimulating nerves and detecting
responses. For instance, nervous tissue may be stimulated by
applying direct or proximate pressure on the nerve, which may cause
the nerve to generate an electrical signal that can be either
observed visually by a muscular twitch or monitored electrically by
detecting evoked response potentials. Nervous tissue may also be
stimulated by applying direct or proximate electrical current,
which can be modulated to increase or decrease the response of the
nerve. Higher currents may result in increased response, but may
also tend to degrade the ability to localize the stimulated nerve
more accurately. Bipolar electrical stimulation may overcome this
by creating localized field currents and placing location
identification within the confines of the applied field. Electrical
stimulation may be provided through a single surface electrode,
multiple surface electrodes, inserted electrodes, interoperative
probes or needles used in the surgical field during surgery, and/or
in numerous other ways. Heat may also be used to stimulate nervous
tissue, since nervous tissue may provide a detectable response to
heat. For instance, heat may be applied using a probe, focused
electromagnetic energy such as a microwave, laser, or focused
ultrasound. As yet another merely illustrative example, focused
high intensity magnetic field gradients may be used to stimulate
nerves, which may enable detection of such nerves. Various examples
of how the above-described nerve stimulation/detection techniques
may be incorporated into a surgical instrument (such as instruments
(10, 50) described above, etc.) will be described in greater detail
below; while others will be apparent to those of ordinary skill in
the art in view of the teachings herein.
[0032] In the present example, power source (418) is in
communication with end effector (412) such that power source (418)
can provide AC and/or DC current to tissue through end effector
(412) to thereby stimulate the tissue, which may in some cases
include the stimulation of nervous tissue. In some versions (e.g.,
versions where direct current is provided through an ultrasonic
blade at end effector (412), etc.), a conventional surgical ground
pad may be placed under the patient to facilitate the flow of DC
electrical current by providing a return path. By way of example
only, this may be readily implemented in versions of instrument
(400) where end effector (412) includes an ultrasonic blade but no
clamping member (e.g., as taught in U.S. Pat. Pub. No.
2008/0200940, etc.), versions of instrument (400) where end
effector (412) includes a clamping member and is configured for use
in open procedures (e.g., as taught in U.S. Pat. Pub. No.
2007/0191713 and/or U.S. Pat. Pub. No. 2007/0282333, etc.), and
versions of instrument (400) where end effector (412) includes a
clamping member and is configured for use in laparoscopic
procedures (e.g., as taught in U.S. Pat. Pub. No. 2006/0079874,
etc.). Other suitable types of instruments that may incorporate the
above teachings will be apparent to those of ordinary skill in the
art in view of the teachings herein.
[0033] As another merely illustrative example, a ground pad may be
omitted and a clamping member (e.g., clamp pad (86), etc.) at end
effector (412) may provide a return path for the nerve stimulus
current. By way of example only, such functionality may be readily
incorporated into versions of instrument (400) where end effector
(412) includes a clamping member and is configured for use in open
procedures (e.g., as taught in U.S. Pat. Pub. No. 2007/0191713
and/or U.S. Pat. Pub. No. 2007/0282333, etc.) and versions of
instrument (400) where end effector (412) includes a clamping
member and is configured for use in laparoscopic procedures (e.g.,
as taught in U.S. Pat. Pub. No. 2006/0079874, etc.). Other suitable
types of instruments that may incorporate the above teachings will
be apparent to those of ordinary skill in the art in view of the
teachings herein. It should also be understood that a ground pad
may still be used under the patient even in instances where a
clamping member at end effector (412) provides an electrical return
path.
[0034] As yet another merely illustrative example, instead of
delivering a nerve stimulus current through an ultrasonic blade at
end effector (412), a clamping member (e.g., clamp pad (86), etc.)
at end effector (412) may be used to deliver a nerve stimulus
current to tissue. In some such versions, a conventional surgical
ground pad may be placed under the patient to facilitate the flow
of DC electrical current by providing a return path. As a variation
of this, an ultrasonic blade at end effector (412) may be used to
provide a return path for the nerve stimulus current, in addition
to or in lieu of using a ground pad under the patient to provide a
return path for the nerve stimulus current. As still another merely
illustrative variation, a clamping member (e.g., clamp pad (86),
etc.) at end effector (412) may include a pair of nerve stimulus
electrodes that are used to provide a nerve stimulus current to
tissue. Such electrodes may be spaced apart from each other
laterally and/or longitudinally, with a dielectric coating and/or
other insulator positioned between the electrodes. Other
configurations for providing nerve stimulus current through end
effector (412) will be apparent to those of ordinary skill in the
art in view of the teachings herein.
[0035] As an alternative to regular AC or DC current, pulsatile
current may be provided through end effector (412). By way of
example only, a suitable pulsatile current may have a pulse width
of approximately 0.05 to 5 milliseconds, a pulse repetition rate of
approximately 0.2 to 100 Hz, and amplitude between approximately
0.1 and 10 mA with a corresponding impedance range of less than
approximately 500 ohms to 10 kohms. It will be understood that
these parameters may be independently adjusted, based on a variety
and/or combination of factors including but not limited to the
following: the amplitude of the evoked response from the nervous
tissue, the threshold amount of current to be applied to cause an
evoked response from the nervous tissue, the latency between the
stimulus and the evoked response, the thickness of the nervous
fibers that may be stimulated, etc. The amplitude of evoked
response may depend on factors such as the number of nerve fibers
that are stimulated (e.g., the larger the nerve bundle and/or the
deeper the penetration of the stimulating current, the greater the
measured amplitude of evoked response, etc.). It should be
understood that once the applied current exceeds the threshold
amount required to cause an evoked response from the nervous
tissue, further increases in current may depolarize an increasing
region of tissue and may thus suppress the response time o the
tissue to subsequent stimulus. It should also be understood that
the latency between the stimulus and the evoked response may be
increased if the stimulating current saturates the nerve; and that
the latency may be indicative of the local environment around the
nerve (e.g., skeletonization may increase latency and/or the length
of nerve fiber traveled from the point of firing to the point of
measurement.
[0036] Of rouse, power source (418) may be operable to provide a
variety of different types and combinations of types of nerve
stimulus in a surgical procedure.
[0037] B. Exemplary Nerve Stimulus Detection
[0038] There are numerous ways to monitor responses to nervous
tissue stimuli. For instance, a sensor may be used to detect evoked
potentials generated by stimulated nerves, including spontaneous
nerve activity by sensory and somatic nerves. It should also be
understood that nerve stimulation may be monitored through
electromyography (EMG). An example of this is described in U.S.
Pub. No. 2009/0033486, entitled "System and Method for Facial Nerve
Monitoring," published Feb. 5, 2009, the disclosure of which is
incorporated by reference herein. Of course, another technique may
include visual observation of muscle twitching caused by nerve
stimulus. As another merely illustrative example, nerve conduction
may be monitored. Nerves may have a characteristic response to a
periodic stimulation. If the intervening nerves are damaged, then
this damage may be evidenced by a change in this characteristic
response. Observed changes may include amplitude, rise time, fall
time, persistence, latency, etc. As yet another merely illustrative
example, motor evoked potentials may be monitored. An example of
this is Transcranial Electric Motor Evoked Potential (TCeMEP),
where the motor cortex is stimulated transcranially, and recordings
are made from muscles in the limbs, or from the spinal cord caudal
to the surgery. Yet another merely illustrative example may include
the use of one or more mechanical sensors adjacent tissue to detect
twitching or other movement of stimulated nervous tissue. Various
examples of how monitoring techniques like those described above
may be incorporated into a surgical instrument (such as instruments
(10, 50) described above, etc.) will be described in greater detail
below; while others will be apparent to those of ordinary skill in
the art in view of the teachings herein.
[0039] It should be understood that providing an appropriate level
of AC current through nervous tissue may cause the tissue to
visibly twitch. Such twitching may be visually observable by the
surgeon by simply seeing the twitching. It may nevertheless be
desirable in some instances (e.g., where visibility of stimulated
tissue is obstructed or otherwise limited, etc.) to provide
additional sensing of reactions in nervous tissue in response to an
electrical current or other form of stimulus. To that end, end
effector (412) of surgical instrument (400) comprises a sensor
(420), indicator (422), and switch (414). Sensor (420), indicator
(422), switch (414), and end effector (412) are in communication
with each other. Sensor (420) may comprise any suitable type of
sensor. For example, sensor (420) may comprise an electrical
impedance sensor/monitor, a vibration sensor, a Doppler fiber
operable to sense acoustic changes, a pressure or torque sensor, a
heat sensor, one or more electrodes built on/into the surface of
end effector (412), or even an electrical wire operable to transmit
electrical current that can be measured, which may be operable to
detect the presence of nervous tissue. By way of example only,
sensor (420) may be configured to sense evoked response potentials
generated in nervous tissue in response to a stimulus. Such
versions may include one or more electrodes that are amplified to
enhance the signal-to-noise ratio associated with sensed evoked
response potentials. Sensor (420) may be integrally formed with end
effector (412) (e.g., integrated into an ultrasonic blade and/or
clamping member, etc.) or may be positioned on the outside of end
effector (412) as would be apparent to one of ordinary skill in the
art in view of the teachings herein.
[0040] As can also be seen in FIG. 3, indicator (422) is in
communication with end effector (412). In some versions, indicator
(422) may be positioned on or within handle assembly (410) or any
other suitable location. In the exemplary version, indicator (422)
is operable to inform the user that end effector (412) is near, or
is touching, nervous tissue. In particular, sensor (420) detects
the nervous tissue and subsequently, control board (416) triggers
indicator (422) to tell the user that nervous tissue has been
reached. In some versions, indicator (422) may include a
selectively illuminated light, a color changing light, a buzzer or
other audio sound, or a vibration generator that tactile/haptic a
physical feedback for the user through handle assembly (410). It
will be appreciated that indicator (422) may take other forms as
would be apparent to one of ordinary skill in the art in view of
the teachings herein. By way of example only, indicator (422) may
be provided as part of power source (418) in addition to or in lieu
of being incorporated into end effector (412). In some such
versions, power source (418) may also be configured to provide an
indication to the surgeon when end effector (412) is in an active
state (e.g., when an ultrasonic blade is being activated). Thus,
power source (418) may be configured to provide both an indication
of when end effector (412) is in an active state and when end
effector (412) is near or touching nervous tissue. For instance,
power source (418) may provide a continuous audible tone at one
octave to indicate activation of end effector (412) and another
audible tone at a higher or lower octave to indicate proximity to
nervous tissue. As another merely illustrative example, such
audible tones may be provided in periodically repetitive pairs.
Still other suitable ways in which power source (418) may provide
audible feedback simultaneously indicating two (or more) different
conditions will be apparent to those of ordinary skill in the art
in view of the teachings herein.
[0041] In some versions, switch (414) may be incorporated into end
effector (412). Switch (414) is operable to selectively activate or
deactivate algorithms, routines, programs, executable functions,
etc., run by control board (416) for delivering nerve stimulus AC
current to end effector (412). Alternatively, switch (414) can be
used to selectively activate, deactivate, engage, or disengage any
suitable portion of surgical instrument (400). For example, switch
(414) may control the activation of sensor (420). In other words,
it will be understood that depending on the situation, the user may
or may not need to detect the presence of nervous tissue, which can
accordingly be controlled via switch (414). While switch (414) is
in communication with end effector (412) in the present example, it
will be appreciated that switch (414) may be located on handle
assembly (410), power source (418), or a module located between
power source (418) and handle assembly (410). Other suitable
locations for switch (414) will be apparent to one of ordinary
skill in the art in view of the teachings herein. Switch (414) may
also take a variety of forms such as a toggle switch, a slider
switch, one or more buttons, or any other suitable type of switch
(414) as would be apparent to one of ordinary skill in the art. It
will further be understood that in some instances, switch (414) may
be omitted entirely such that sensor (420) and the associated
components continually detect nervous tissue.
[0042] In yet other variations, it will be appreciated that sensor
(420), switch (414), and indicator (422) may be modularly attached
to end effector (412) such that they may be moved, or used in
conjunction with a different surgical device and/or instrument. Yet
in some versions, sensor (420), switch (414), and indicator (422)
may be constructed such that they are integrally formed with end
effector (412) and/or handle assembly (410) or a shaft extending
from handle assembly (410).
[0043] C. Exemplary Surgical Instrument with Dual Function Blade
and Sensing Clamp Arm
[0044] FIG. 4 shows one exemplary version of a surgical instrument
(500) having a shaft (502) leading to an end effector (512). End
effector (512) comprises a blade (579) and clamp arm (584) operable
to clamp tissue to deliver RF energy, ultrasonic vibration energy,
or any other suitable type of surgical/therapeutic energy. Power
source (518) is operable to drive blade (579) to deliver such
surgical/therapeutic energy to tissue. It will be appreciated that
in addition to surgical/therapeutic energy used for cutting,
cauterizing, etc., blade (579) is operable to deliver electrical
energy (e.g., DC/AC/pulsatile current) capable of stimulating nerve
cells, fibers, and/or tissue. By delivering such energy, nervous
tissue near end effector (512) may become excited, resulting in a
variety of actions as described above. For example, nervous tissue
may twitch, experience a change in impedance, may experience a
change in electrical activity, exhibit an evoked potential or other
response, etc. Other perceivable changes to nervous tissue may
occur as would be apparent to one of ordinary skill in the art in
view of the teachings herein. It should be understood that clamp
arm (584) is shown merely as an illustrative example. The teachings
herein may be readily applied to variations of end effector (512)
that lack a clam arm (584). For instance, the teachings herein may
be readily applied to versions of end effector (512) that just have
blade (579).
[0045] It will be understood that energy delivered through blade
(579) for cutting or other surgical/therapeutic purposes may be
distinguished from energy for stimulating/exciting nervous tissue
in a variety of ways. For example, energy for cutting may have a
different phase in comparison to energy for excitation. In other
versions, energy for cutting may be delivered in a particular
series of pulses while energy for nerve stimulus may be delivered
between the pulses of the cutting energy. In yet other versions,
energy for cutting and excitation may be multiplexed during
delivery. In versions where surgical instrument (500) is an
ultrasonic surgical instrument and blade (579) is an ultrasonic
blade, the energy for cutting is a mechanical oscillation movement
while the energy for excitation is electrical current. It will be
appreciated that other ways of distinguishing energy for cutting
and energy for excitation will be apparent to one of ordinary skill
in the art in view of the teachings herein.
[0046] As with sensor (42) described above, sensor (520) is
operable to detect changes associated with excited nervous tissue
and is integrated into clamp arm (584). Surgical instrument (500)
also comprises a pad (580) in communication with clamp arm (584)
operable to prevent direct communication of energy from blade (579)
to clamp arm (584). As a result, it will be appreciated that energy
detected by sensor (520) is a result of excitation of nervous
tissue rather than by a direct transfer of energy from blade (579)
to clamp arm (584). Furthermore, in some versions, sensor (520) may
be tuned or configured to avoid false positives in response to
surgical and/or therapeutic activations of blade (579). In addition
or in the alternative, a control logic/algorithm in communication
with sensor (520) may be configured to distinguish between
excitations caused by surgical/therapeutic activations of blade
(579) and excitations caused by a nerve stimulus current. In
versions where clamp arm (584) is omitted, sensor (520) may be
incorporated into blade (579) and/or some other part of surgical
instruments (500) in numerous ways that will be apparent to those
of ordinary skill in the art in view of the teachings herein.
[0047] In the exemplary version, sensor (520) is shaped like a
blunt crescent. Sensor (520) is positioned on clamp arm (584) at or
around the distal tip of clamp arm (584) such that sensor (520)
protrudes past clamp arm (584). Thus, when blade (579) and clamp
arm (584) clamp around tissue, sensor (520) protrudes into or
around surrounding tissue. It will be understood that sensor (520)
may have any suitable shape. For example, in some versions, sensor
(520) may cover clamp arm (584) entirely. In yet other exemplary
versions, sensor (520) may comprise multiple sensors (520) spaced
apart along clamp arm (584). Other suitable variations will be
apparent to one of ordinary skill in the art in view of the
teachings herein.
[0048] It will be appreciated that in some versions, sensor (520)
may require electrical energy to function properly. Such energy may
be delivered in some instances based on the opening and closing of
clamp arm (584) in relation to blade (579). A joint (513) that
joins clamp arm (584) and blade (579) may be integrated with a
joint switch (515) such that once clamp arm (584) opens and reaches
a certain angle in relation to blade (579), joint switch (515)
triggers delivery of power to sensor (520) such that sensor (520)
can then detect excited nervous tissue. In some versions, joint
(513) may comprise a feedback mechanism, such as a detent, such
that the user receives haptic feedback that clamp arm (584) has
opened widely enough to trigger operation of sensor (520). The
haptic feedback may include a click or vibration pulse, or any
other suitable feedback. In some instances, rather than haptic
feedback, surgical instrument (500) may illuminate a light such as
an LED or output an audible cue. In yet other variations, no
feedback may be provided at all, and sensor (520) may simply be
activated without informing the user. In some instances, the actual
activation of sensor may be delayed slightly for a duration of
approximately 2 seconds. It will be appreciated that any suitable
delay may be incorporated between the triggering of joint switch
(515) and operation of sensor (520) to provide the user sufficient
notice that sensor (520) will be activated. Additionally, in some
versions, turning off sensor (520) may be achieved by closing clamp
arm (584) and blade (579) past a certain angle or simply by opening
clamp arm (584) in relation to blade (579) a second time in such a
way that triggers joint switch (515) a second time. As sensor (520)
turns off, surgical instrument (500) may provide the user with
feedback (mechanical, visual, and/or audio, etc.) to inform the
user that sensor (520) has been turned off.
[0049] As discussed above, sensor (520) may be operable to detect
excited nervous tissue. As a result, as blade (579) provides
excitation of nervous tissue, sensor (520) then detects those
excitations allowing a user to determine whether to avoid or
otherwise respond to the presence/proximity of such nervous tissue.
Sensor (520) is also in communication with an indicator (522) such
that indicator (522) is activated when sensor (520) detects nervous
tissue. A user will thus be able to monitor indicator (522) as the
user uses surgical instrument (500) to determine whether nervous
tissue is nearby or has come into contact with clamp arm (584). As
with other components, indicator (522) is merely optional. For
instance, a surgeon may simply rely on visual observation of tissue
twitching to detect excitation of nervous tissue. In other
versions, the user may use an endoscope to view any twitching of
nervous tissue. Other suitable imaging or visual aids may be used
as would be apparent to one of ordinary skill in the art in view of
the teachings herein.
[0050] FIGS. 5A-5B show an exemplary use of surgical instrument
(500) as applied to tissue (590). In the illustrated version,
surgical instrument (500) is configured to deliver ultrasonic
energy to tissue (590) via end effector (512). However, it will be
appreciated that surgical instrument (500) may be selected to
perform any suitable surgical procedure for which it may be
desirable to determine the proximity of nervous tissue. FIG. 5A
shows surgical instrument (500) as it approaches tissue (590) to
cut. Clamp arm (584) is open in relation to ultrasonic blade (579).
FIG. 5B shows clamp arm (584) closed toward blade (579) with tissue
(590) clamped between clamp arm (584) and blade (579). Pad (580) is
positioned between clamp arm (584) and tissue. Additionally, in
FIG. 5B, ultrasonic cutting energy is transmitted to tissue (590)
via blade (579), thereby cutting tissue (590). At or around the
same time, electrical current is transmitted through blade (579) to
stimulate/excite nervous tissue. As can be seen in the exemplary
version, excitation of nerves near tissue (590) that has been cut
by surgical instrument (500) may result in either twitching or
otherwise measurable excitation of nervous tissue. Sensor (520) is
able to detect such nervous tissue excitation. Once sensor (520)
detects excited nervous tissue (592), sensor (520) then triggers
indicator (522), which may comprise a visual or audio signal to
alert the user to know that nervous tissue is nearby. Thereafter,
the user may react accordingly.
[0051] In some instances, sensor (520) may affect delivery of
ultrasonic energy to blade (579) when sensor (520) detects
excitation of nervous tissue (592). For instance, sensor (520) may
be coupled with a logic in communication with the transducer
activation circuit, and may at least temporarily cut electrical
power to the transducer when sensor (520) detects excitation of
nervous tissue (592), thereby rendering blade (579) inactive before
blade (579) cuts the nervous tissue (592). In some such versions,
the system may require the surgeon to reposition the end effector
then release and re-actuate a trigger button or lever in order to
re-activate the ultrasonic transducer. Similarly, before blade
(579) is activated with ultrasonic energy (e.g., at the beginning
of a surgical procedure), a control logic may drive the nerve
stimulus feature and check feedback from sensor (520), and prevent
blade (579) from being activated unless sensor (520) fails to
indicate the presence/proximity of nervous tissue. In addition or
in the alternative, the system may provide a surgeon override
feature enabling the surgeon to selectively continue activation of
the ultrasonic transducer despite the proximity of blade (579) to
nervous tissue. In addition or in the alternative to affecting
activation of the ultrasonic transducer, sensor (520) may trigger
delivery of a therapeutic substance or other type of substance via
the end effector of surgical instrument (500) when sensor (520)
detects excitation of nervous tissue (592). Either or both of these
functionalities, among others that will be apparent to those of
ordinary skill in the art in view of the teachings herein, may be
provided in addition to or in lieu of triggering indicator
(522).
[0052] It should also be understood that responses triggered by
sensor (520) may vary based on the level of nervous tissue
excitation detected by sensor (520). For instance, a small degree
of excitation detected by sensor (520) may simply result in
triggering of indicator (522) to warn the surgeon that they are
starting to approach nervous tissue; while a large degree of
excitation detected by sensor (520) may result in at least
temporary cutoff of electrical power to the ultrasonic
transducer.
[0053] Similarly, indicator (522) may itself react differently
based on levels of nervous tissue excitation detected by sensor
(520) (e.g., flashing a yellow light and/or providing relatively
infrequent audible tone pulses in response to a small degree of
excitation; and flashing a red light and/or providing relatively
rapid audible tone pulses in response to a large degree of
excitation). Indicator (522) may also produce an audible signal to
indicate surgical instrument (500) is in an "on" state and a
further audible signal to indicate proximity of nervous tissue. For
instance, indicator (522) may produce different tones such as a
lower pitch tone indicating an "on" state and a higher pitch tone
indicating contact with nervous tissue. As another merely
illustrative example, indicator (522) may produce pulsed tones with
a frequency indicative of proximity to nervous tissue. For
instance, indicator (522) may produce periodic tones with a low
frequency providing relatively long delay between the tones when
nervous tissue is not in significant proximity to end effector
(512); with an increasing frequency providing progressively shorter
delay between the tones when end effector (512) approaches nervous
tissue.
[0054] In some instances, surgical instrument (500) may be used to
establish a nerve tissue map by the user. For example, sensor (520)
may be operable to detect nervous tissue that is excited by
surgical instrument (500), and a map may be generated based on
feedback from sensor (520) and/or based on feedback from other
instrument (500) components (e.g., accelerometers, etc.). In
addition to nervous tissue detection, surgical instrument (500) may
be operable to determine the spatial location of surgical
instrument (500) such that detection of nervous tissue by sensor
(520) may be associated with a spatial location. As the user
detects nervous tissue by sensor (520) along several points in
space, a map of the nervous tissue may be formed such that the user
may more accurately be able to manipulate surgical instrument (500)
in relation to such nervous tissue indicated by the nervous tissue
map.
[0055] In some instances, surgical instrument (500) may produce
heat that transfers to tissue, including nervous tissue, during
normal use of surgical instrument (500). It may be desirable to
determine if nervous tissue or nearby tissue conducts such heat.
Sensor (520) may thus be operable to detect transferred heat
directly through thermal detection or may be operable to detect
changes in electrical properties of nervous tissue affected by heat
(e.g., nervous tissue might exhibit a higher signal to noise
alteration of evoked potential in response to heat). In some
instances, once a certain threshold of heat has been detected,
surgical instrument (500) may then notify the user.
[0056] FIG. 6 shows an exemplary method (600) of using surgical
instrument (500). As an initial step (610), the user may activate
surgical instrument (500). In some cases, surgical device may be
automatically activated as soon as power is supplied to the power
source of surgical instrument (500), and in other versions, the
user may select when to turn on surgical instrument (500). At or
around the time where surgical instrument (500) is turned on by the
user, user may insert surgical instrument (500) into the surgical
site to be used in the surgical procedure.
[0057] Step (620) involves operating the surgical instrument (500).
In the case of an ultrasonic surgical instrument (500), surgical
instrument (500) may deliver ultrasonic vibrations through blade
(579) to the surgical site. Such vibrations may be produced by
pulsing electrical power to a transducer of surgical instrument
(500). In some versions, an activation pulse is delivered to the
transducer with a frequency ranging from one pulse every 10
milliseconds to one pulse every 100 milliseconds. Of course, any
other suitable pulse frequency may be used as will be apparent to
those of ordinary skill in the art in view of the teachings herein.
These activation pulses cause peizeoelectric elements in the
transducer to convert the electrical power into mechanical
oscillatory/vibrational power, resulting in ultrasonic oscillations
that are communicated along an acoustic waveguide to the ultrasonic
blade (579). Between the electrical activation pulses delivered to
the transducer to produce ultrasonic vibrations, surgical
instrument (500) also delivers electrical current for the detection
of nervous tissue. Such stimulus current may also be delivered
through the transducer, waveguide, and blade (579), without
compromising the acoustic performance of these components. For
instance, the parameters of the nerve stimulus electrical current
may be selected to not excite the piezoelectric elements in the
transducer. Some versions of surgical instrument (500) may be
operable to deliver nerve stimulus electrical current at the same
time as transducer activation pulses. For instance, the electrical
path for the nerve stimulus electrical current may be completely
separate and isolated relative to the electrical path for
activation of the transducer. Other variations for providing
electrical current for nervous tissue detection and ultrasonic
transducer activation will be apparent to one of ordinary skill in
the art in view of the teachings herein.
[0058] In some instances, during the step (620) of operating
surgical instrument (500), ultrasonic vibrations provided by
surgical instrument (500) may be used to provide pressure to
nervous tissue, thereby resulting in detectable changes to nervous
tissue as the nervous tissue is excited, which allows the user to
locate the nervous tissue. For example, an amplitude modulated
resonant excitation signal may be produced by an ultrasonic
transducer of surgical instrument (500) to excite nervous tissue.
As another merely illustrative example, a frequency modulated
resonant signal or a pulse width modulated resonant frequency may
be produced that alternates in the time domain with the resonant
frequency. In yet other instances, end effector (512) of surgical
instrument (500) may be shaped such that during usage of surgical
instrument in step (620), cavitational pressure may be generated
around nervous tissue that excites or otherwise produces a
measureable change in nervous tissue. In yet other versions, a
separate acoustic driver could be used in step (620) during use of
surgical instrument (500), which may be operable to create an
acoustic wave in nervous tissue, thereby exciting it in a
measurable manner.
[0059] The user in step (630) simply observes the site to determine
whether excitation of nervous tissue has occurred. It will be
appreciated that at least in some instances, nervous tissue will
twitch and/or become visibly excited in a manner proportional to
the closeness and strength of the energy being delivered to the
nervous tissue. Energy for detecting nervous tissue may be
continually delivered by returning to step (620), which thereby
allows a user to continually monitor whether nervous tissue is
nearby or otherwise in danger of being harmed. In some instances,
the user may survey a surgical area by using surgical instrument
(500) prior to activating blade (579) for surgical and/or
therapeutic purposes. By doing so, the user can observe nervous
tissue response and determine what areas of a surgical site contain
nervous tissue before cutting tissue. The surgeon may still
nevertheless wish to continue the stimulus and monitoring
throughout the surgical procedure, even if the surgeon had
performed a stimulus survey of the surgical site before activating
blade (579) for surgical and/or therapeutic purposes.
[0060] During step (630), it will be understood that energy for
exciting and subsequently detecting nervous tissue may be
transmitted through blade (579) or through clamp arm (584)
separately. In other versions, energy for exciting and detecting
nervous tissue may be transmitted through both blade (579) and
clamp arm (584) simultaneously. In yet other versions, energy for
detecting nervous tissue may be transmitted through blade (579)
while clamp arm (584) is omitted entirely. Other suitable
variations will be apparent to one of ordinary skill in the art in
view of the teachings herein.
[0061] While the exemplary version contemplates the user visually
monitoring nervous tissue twitch, it will be appreciated that in
some versions, an indicator may be used to signal the proximity of
nervous tissue. Such an indicator may be constructed as discussed
with respect to indicator (522) shown in FIGS. 5A-5B. It will
further be contemplated that such an indicator may be operable to
indicate the closeness of nervous tissue, by, for example,
producing a brighter visual indicator or louder audio indicator as
surgical instrument (500) moves closer to nervous tissue.
[0062] In some versions, it will be appreciated that surgical
instrument (500) may be used in a patient having other medical
devices including implants, fasteners, or other instruments at or
near the surgical site. In those situations, it may be desirable to
gauge proximity of surgical instrument (500) to such items. It will
be appreciated that in some instances, such items may be metallic,
plastic, or any other material providing a change in the electrical
properties of the surrounding tissue. Accordingly, the electrical
stimulus and sensing mechanisms of surgical instrument (500) may
detect the proximity of those items. Other suitable uses for
surgical instrument (500) will be apparent to one of ordinary skill
in the art.
[0063] While examples above related to surgical instrument (10) in
the form of an ultrasonic surgical instrument, it should be
understood that the teachings herein may be readily applied to
various types of electrosurgical instruments, including but not
limited to those taught in U.S. Pat. No. 6,500,176 entitled
"Electrosurgical Systems and Techniques for Sealing Tissue," issued
Dec. 31, 2002, the disclosure of which is incorporated by reference
herein; U.S. Pat. No. 7,112,201 entitled "Electrosurgical
Instrument and Method of Use," issued Sep. 26, 2006, the disclosure
of which is incorporated by reference herein; U.S. Pat. No.
7,125,409, entitled "Electrosurgical Working End for Controlled
Energy Delivery," issued Oct. 24, 2006, the disclosure of which is
incorporated by reference herein; U.S. Pat. No. 7,169,146 entitled
"Electrosurgical Probe and Method of Use," issued Jan. 30, 2007,
the disclosure of which is incorporated by reference herein; U.S.
Pat. No. 7,186,253, entitled "Electrosurgical Jaw Structure for
Controlled Energy Delivery," issued Mar. 6, 2007, the disclosure of
which is incorporated by reference herein; U.S. Pat. No. 7,189,233,
entitled "Electrosurgical Instrument," issued Mar. 13, 2007, the
disclosure of which is incorporated by reference herein; U.S. Pat.
No. 7,220,951, entitled "Surgical Sealing Surfaces and Methods of
Use," issued May 22, 2007, the disclosure of which is incorporated
by reference herein; U.S. Pat. No. 7,309,849, entitled "Polymer
Compositions Exhibiting a PTC Property and Methods of Fabrication,"
issued Dec. 18, 2007, the disclosure of which is incorporated by
reference herein; U.S. Pat. No. 7,311,709, entitled
"Electrosurgical Instrument and Method of Use," issued Dec. 25,
2007, the disclosure of which is incorporated by reference herein;
U.S. Pat. No. 7,354,440, entitled "Electrosurgical Instrument and
Method of Use," issued Apr. 8, 2008, the disclosure of which is
incorporated by reference herein; U.S. Pat. No. 7,381,209, entitled
"Electrosurgical Instrument," issued Jun. 3, 2008, the disclosure
of which is incorporated by reference herein; U.S. Pub. No.
2011/0087218, entitled "Surgical Instrument Comprising First and
Second Drive Systems Actuatable by a Common Trigger Mechanism,"
published Apr. 14, 2011, the disclosure of which is incorporated by
reference herein; and U.S. patent application Ser. No. 13/151,181,
entitled "Motor Driven Electrosurgical Device with Mechanical and
Electrical Feedback," filed Jun. 2, 2011, the disclosure of which
is incorporated by reference herein.
[0064] Furthermore, the teachings herein may be readily applied to
various types of electrically powered cutting and stapling
instruments, including but not limited to those taught in U.S. Pat.
No. 7,416,101 entitled "Motor-Driven Surgical Cutting and Fastening
Instrument with Loading Force Feedback," issued Aug. 26, 2008, the
disclosure of which is incorporated by reference herein; U.S. Pub.
No. 2009/0209979, entitled "Motorized Cutting and Fastening
Instrument Having Control Circuit for Optimizing Battery Usage,"
published Aug. 20, 2009; and U.S. patent application Ser. No.
13/151,181, entitled "Motor Driven Electrosurgical Device with
Mechanical and Electrical Feedback," filed Jun. 2, 2011, the
disclosure of which is incorporated by reference herein. Still
other suitable types of devices to which the teachings herein may
be applied will be apparent to those of ordinary skill in the
art.
[0065] It should be appreciated that any patent, publication, or
other disclosure material, in whole or in part, that is said to be
incorporated by reference herein is incorporated herein only to the
extent that the incorporated material does not conflict with
existing definitions, statements, or other disclosure material set
forth in this disclosure. As such, and to the extent necessary, the
disclosure as explicitly set forth herein supersedes any
conflicting material incorporated herein by reference. Any
material, or portion thereof, that is said to be incorporated by
reference herein, but which conflicts with existing definitions,
statements, or other disclosure material set forth herein will only
be incorporated to the extent that no conflict arises between that
incorporated material and the existing disclosure material.
[0066] Versions of the present invention have application in
conventional endoscopic and open surgical instrumentation as well
as application in robotic-assisted surgery. An exemplary
robotic-assist surgery system is disclosed in U.S. Pat. No.
6,783,524, entitled "Robotic Surgical Tool with Ultrasound
Cauterizing and Cutting Instrument," published Aug. 31, 2004, the
disclosure of which is incorporated by reference herein.
[0067] Versions of the devices disclosed herein can be designed to
be disposed of after a single use, or they can be designed to be
used multiple times. Versions may, in either or both cases, be
reconditioned for reuse after at least one use. Reconditioning may
include any combination of the steps of disassembly of the device,
followed by cleaning or replacement of particular pieces, and
subsequent reassembly. In particular, versions of the device may be
disassembled, and any number of the particular pieces or parts of
the device may be selectively replaced or removed in any
combination. Upon cleaning and/or replacement of particular parts,
versions of the device may be reassembled for subsequent use either
at a reconditioning facility, or by a surgical team immediately
prior to a surgical procedure. Those skilled in the art will
appreciate that reconditioning of a device may utilize a variety of
techniques for disassembly, cleaning/replacement, and reassembly.
Use of such techniques, and the resulting reconditioned device, are
all within the scope of the present application.
[0068] By way of example only, versions described herein may be
processed before surgery. First, a new or used instrument may be
obtained and if necessary cleaned. The instrument may then be
sterilized. In one sterilization technique, the instrument is
placed in a closed and sealed container, such as a plastic or TYVEK
bag. The container and instrument may then be placed in a field of
radiation that can penetrate the container, such as gamma
radiation, x-rays, or high-energy electrons. The radiation may kill
bacteria on the instrument and in the container. The sterilized
instrument may then be stored in the sterile container. The sealed
container may keep the instrument sterile until it is opened in a
surgical facility. A device may also be sterilized using any other
technique known in the art, including but not limited to beta or
gamma radiation, ethylene oxide, or steam.
[0069] Having shown and described various versions of the present
invention, further adaptations of the methods and systems described
herein may be accomplished by appropriate modifications by one of
ordinary skill in the art without departing from the scope of the
present invention. Several of such potential modifications have
been mentioned, and others will be apparent to those skilled in the
art. For instance, the examples, versions, geometrics, materials,
dimensions, ratios, steps, and the like discussed above are
illustrative and are not required. Accordingly, the scope of the
present invention should be considered in terms of the following
claims and is understood not to be limited to the details of
structure and operation shown and described in the specification
and drawings.
* * * * *