U.S. patent application number 16/695310 was filed with the patent office on 2020-09-24 for system for neuronavigation registration and robotic trajectory guidance, robotic surgery, and related methods and devices.
The applicant listed for this patent is GLOBUS MEDICAL, INC.. Invention is credited to Christopher Angelucci, Hayden Cameron, James Cascarano, Stephen Cicchini, Neil R. Crawford, Norbert Johnson, Sanjay Joshi, Justin Larson, Spiros Mantzavinos, Ross Morris.
Application Number | 20200297357 16/695310 |
Document ID | / |
Family ID | 1000004526756 |
Filed Date | 2020-09-24 |
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United States Patent
Application |
20200297357 |
Kind Code |
A1 |
Cameron; Hayden ; et
al. |
September 24, 2020 |
SYSTEM FOR NEURONAVIGATION REGISTRATION AND ROBOTIC TRAJECTORY
GUIDANCE, ROBOTIC SURGERY, AND RELATED METHODS AND DEVICES
Abstract
A system for robotic surgery makes use of an end-effector which
has been configured so that a drill connected thereto is guided in
its trajectory and limited in its advancement into an associated
anatomical feature by a drill guide. The drill guide may be
adjusted manually to engage a corresponding surface of the drill
after its advancement by a pre-selected amount. The drill guide
likewise includes features to guide the drill during trajectories
having oblique angles relative to the surface of the anatomical
feature associated with the medical procedure.
Inventors: |
Cameron; Hayden;
(Philadelphia, PA) ; Mantzavinos; Spiros; (Nashua,
NH) ; Crawford; Neil R.; (Chandler, AZ) ;
Joshi; Sanjay; (Andover, MA) ; Johnson; Norbert;
(North Andover, MA) ; Cascarano; James;
(Cambridge, MA) ; Larson; Justin; (Somerville,
MA) ; Cicchini; Stephen; (North Wales, PA) ;
Morris; Ross; (Norristown, PA) ; Angelucci;
Christopher; (Schwenksville, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GLOBUS MEDICAL, INC. |
Audubon |
PA |
US |
|
|
Family ID: |
1000004526756 |
Appl. No.: |
16/695310 |
Filed: |
November 26, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16452737 |
Jun 26, 2019 |
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16695310 |
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16361863 |
Mar 22, 2019 |
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16452737 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 2034/2055 20160201;
A61B 90/11 20160201; A61B 2034/2072 20160201; A61B 2017/00407
20130101; A61B 90/03 20160201; A61B 17/1695 20130101; A61B 34/20
20160201; A61B 17/162 20130101; A61B 34/30 20160201; A61B 90/08
20160201; A61B 90/14 20160201; A61B 2090/0807 20160201; A61B
17/1739 20130101; A61B 2034/2051 20160201; A61B 2090/034
20160201 |
International
Class: |
A61B 17/16 20060101
A61B017/16; A61B 34/30 20060101 A61B034/30; A61B 17/17 20060101
A61B017/17; A61B 34/20 20060101 A61B034/20; A61B 90/14 20060101
A61B090/14; A61B 90/00 20060101 A61B090/00; A61B 90/11 20060101
A61B090/11 |
Claims
1. A surgical robot system for surgery on an anatomical feature of
a patient, the system comprising: a surgical robot; a robot arm
connected to the surgical robot; an end-effector connected to the
robot arm and orientable to oppose the anatomical feature so as to
be in operative proximity thereto; a processor circuit; a surgical
tool comprising a drill selectively connectible to the
end-effector; a memory accessible by the processor circuit and
comprising machine readable instructions configured, in response to
user input, to determine a drill target and an associated drill
trajectory, the instructions further configured, when executed, to
cause the end-effector to move to a position corresponding to a
determined target and a determined drill trajectory to permit
advancement of the drill toward the target; a drill guide having
proximal and distal ends, the drill guide releaseably connected to
the end-effector at the distal end and to the drill at the proximal
end, wherein the drill guide is configured to stop the advancement
of the drill at a pre-selected drill depth associated with the
determined target and is further configured to guide the drill
along the determined drill trajectory during the advancement of the
drill; wherein the drill includes a chuck having a distal surface
and a rotatable, elongated drill bit extending distally from the
distal surface of the chuck and terminating in a drill tip capable
of engaging the anatomical feature, the drill bit having a first
predetermined length corresponding to the distance between the
distal surface of the chuck and the drill tip; wherein the drill
guide includes a guide shaft having proximal and distal guide shaft
ends, openings at the proximal and distal guide shaft ends,
respectively, and a bore extending between the openings and sized
to slideably receive the drill bit therethrough, the guide shaft
having associated therewith a second, predetermined length; wherein
the drill guide further includes a depth stop having proximal and
distal depth stop ends, the depth stop mounted to the proximal end
of the guide shaft and selectively slidable longitudinally to vary
the second predetermined length to be shorter than the first
predetermined length of the drill bit, so that the drill bit when
received in the guide shaft may be advanced beyond the distal end
of the guide shaft by a preselected amount; wherein the depth stop
has a surface for engaging the distal surface of the chuck of the
drill, whereby the depth to which the drill tip is advanceable by
the drill is limited by an amount corresponding to the position of
the depth stop.
2. The system of claim 1, wherein the drill guide comprises a depth
indicator having indicia corresponding to graduated depths of
advancement of the drill bit associated with the drill guide.
3. The system of claim 2, wherein the depth stop comprises a
longitudinal stem slideably received within the bore of the guide
shaft; wherein the guide shaft has portions forming a window sized
and located to reveal the longitudinal stem received in the guide
shaft; wherein the indicia associated with the graduated depths are
located on at least one of the stem and the portions adjacent the
window to indicate the predetermined drill depth.
4. The system of claim 3, wherein the indicia comprise a pointer
and a numerical value scale moveable relative to each other, the
pointer disposed on one of the stem and the portions adjacent the
window, and the numerical value scale disposed on the other of the
stem and the portions adjacent the window.
5. The system of claim 1, wherein the drill guide comprises an
engagement mechanism to set the depth stop at one of a plurality of
selectable, longitudinal positions corresponding to a desired drill
depth.
6. The system of claim 5, wherein the engagement mechanism
comprises a ratchet assembly engageable at one of the plurality of
longitudinally spaced locations between the proximal and distal
ends of the depth stop.
7. The system of claim 5, wherein the drill guide comprises a
spring-biased trigger actuatable to disengage the engagement
mechanism from a first one of the longitudinal positions and set
the engagement mechanism at a second one of the longitudinal
positions, the second longitudinal position corresponding to the
desired drill depth.
8. The system of claim 7, wherein the trigger comprises a trigger
lock operatively connected to the trigger to inhibit the actuation
of the trigger and thereby inadvertent disengagement of the
engagement mechanism.
9. The system of claim 5, wherein the drill guide comprises a
handle operatively connected to the engagement mechanism to
manually set the depth stop at the selective one of the
longitudinal positions.
10. The system of claim 1, wherein the guide shaft has at least one
bushing disposed within the bore and sized to receive the outer
longitudinal surface of the drill bit slideably and rotatably
therein.
11. The system of claim 10, wherein the guide shaft comprises upper
and lower bushings disposed at longitudinally-spaced locations
within the bore.
12. The system of claim 10, wherein the bushing has an internal
diameter sized to engage the longitudinal surface of the distal end
of the drill bit with a force opposing lateral displacement of the
drill bit within the guide shaft to reduce deviation of the drill
bit from the determined drill trajectory.
13. A method of guiding a drill during robot-assisted surgery on an
anatomical feature of a patient, the method comprising the steps
of: determining, by computer processing, a drill target and an
associated drill trajectory and effectuating movement of an
end-effector to a position corresponding to the determined target
and the determined drill trajectory; manually setting a depth stop
connected to the end-effector to one of a plurality of selectable
positions corresponding to a desired depth of advancement of the
drill relative to the anatomical feature, whereby the drill is
limited from penetrating the anatomical feature beyond the desired
depth.
14. The method of claim 13, wherein the step of setting the depth
stop comprises: displacing the depth stop relative to visually
perceptible indicia, the indicia corresponded to graduated depths
of advancement of the drill; and securing the depth stop at a
desire position corresponding to a selected one of the graduated
depths.
15. The method of claim 14, wherein the steps of displacing and
securing the depth stop comprise: actuating a spring-biased trigger
to disengage the depth stop from a first position; longitudinally
sliding the depth stop relative to the visually perceptible indicia
to a second position, the second position corresponding to the
desired position of the depth stop; and releasing the trigger to
re-engage the depth stop at the desired position.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 16/452,737, filed Jun. 26, 2019, which is a
continuation-in-part of U.S. patent application Ser. No.
16/361,863, filed on Mar. 22, 2019, the entire contents of each of
which are hereby incorporated herein by reference for all
purposes.
FIELD
[0002] The present disclosure relates to medical devices and
systems, and more particularly, systems for neuronavigation
registration and robotic trajectory guidance, robotic surgery, and
related methods and devices.
BACKGROUND
[0003] Position recognition systems for robot assisted surgeries
are used to determine the position of and track a particular object
in 3-dimensions (3D). In robot assisted surgeries, for example,
certain objects, such as surgical instruments, need to be tracked
with a high degree of precision as the instrument is being
positioned and moved by a robot or by a physician, for example.
[0004] Position recognition systems may use passive and/or active
sensors or markers for registering and tracking the positions of
the objects. Using these sensors, the system may geometrically
resolve the 3-dimensional position of the sensors based on
information from or with respect to one or more cameras, signals,
or sensors, etc. These surgical systems can therefore utilize
position feedback to precisely guide movement of robotic arms and
tools relative to a patients' surgical site. Thus, there is a need
for a system that efficiently and accurately provide
neuronavigation registration and robotic trajectory guidance in a
surgical environment.
[0005] End-effectors used in robotic surgery may be limited to use
in only certain procedures, or may suffer from other drawbacks or
disadvantages.
SUMMARY
[0006] According to some implementations, a surgical robot system
is configured for surgery on an anatomical feature of a patient,
and includes a surgical robot, a robot arm connected to such
surgical robot, and an end-effector connected to the robot arm. The
end-effector has a surgical tool selectively connected to it, and
the robot system includes a memory accessible by a suitable
processor circuit which processes machine-readable instructions.
Among the instructions which are executable by the system are ones
which, in response to user input, determine a drill target and an
associated drill trajectory. The instructions also may be executed
to cause the end-effector to move to a position corresponding to
such determined target and determined drill trajectory. Once
positioned in this manner, the system and corresponding
instructions will permit advancement of the aforementioned drill
toward the determined target.
[0007] In certain implementations, the system includes a drill
guide which is connectible between the end-effector and the drill.
The drill guide is configured to stop advancement of the drill at a
pre-selected drill depth associated with the determined target, and
is further configured to guide the drill along the determined drill
trajectory during advancement of the drill. As such, the drill
guide provides further assurance against over-penetration or
over-engagement of the anatomical feature being operated upon and
likewise assists in guiding the trajectory of the drill, including
when such trajectory is oblique to the anatomical feature.
[0008] The drill guide includes a guide shaft with a bore extending
longitudinally therethrough and having proximal and distal openings
to the bore. The guide shaft and the corresponding bore are sized
to slideably receive a drill bit of the drill therethrough, such
drill bit having an associated drill tip and being operatively
connected to advancement and rotating mechanisms of the drill at a
proximal location by a suitable chuck. The drill guide includes a
depth stop which is mounted to the proximal end of the guide shaft
and selectively slideable longitudinally to vary the length of the
guide shaft relative to the predetermined length of the drill bit
received in the drill. The drill stop has a surface located and
otherwise disposed to engage the distal surface of the chuck of the
drill. As such, engagement between the chuck and the depth stop
limits the depth to which the drill tip is advanceable by an amount
corresponding to the position of the depth stop.
[0009] In certain implementations, the drill guide makes use of a
depth indicator having indicia corresponding to graduated depths of
advancement of the drill bit associated with the drill guide during
the operative procedures contemplated by the surgical robot system.
The depth stop may be formed so as to include a longitudinal stem,
this stem being slideably received within the bore of the guide
shaft. The guide shaft, in turn, has a window formed therein which
is sized and located to reveal the longitudinal stem of the depth
stop when it is received in the guide shaft. With such an
arrangement, the aforementioned indicia associated with the
graduated depth may be located either on the longitudinal stem
visible through the window or on portions adjacent to the window,
and such indicia are movable relative to a pointer or other
indicator relative to which the graduated depth scale moves. In
this manner, the desired depth limit may be manually selected by
visually perceiving the numerical value of the graduated depths
aligned with the associated pointer or indicator.
[0010] In still other aspects of the disclosed implementations, the
drill guide has an engagement mechanism to set the depth stop at
one of a plurality of selectable, longitudinal positions
corresponding to the desired drill depth. One suitable engagement
mechanism may include a ratchet assembly engageable at one of a
plurality of longitudinally spaced locations between the proximal
and distal ends of the depth stop. In one suitable implementation,
the ratchet assembly includes a ratchet that may be disengaged and
engaged by actuation or release, respectively, of a spring-biased
trigger. Such trigger may have a trigger lock operatively
associated therewith so that once the ratchet of the ratchet
assembly has engaged the depth stop at a selected longitudinal
position, such trigger lock inhibits inadvertent actuation of the
trigger which would cause disengagement of the ratchet and
potential longitudinal movement of the depth stop. The drill guide
may include a handle operatively connected to the engagement
mechanism so as to manually set the depth stop at the selected one
of the longitudinal positions.
[0011] In still other implementations, the guide shaft has at least
one bushing, and such bushing may be sized to engage the
longitudinal surface at the distal end of the drill bit in such a
manner so as to exert a force on such distal drill bit end to
oppose lateral displacement of the drill bit within the guide
shaft. Such opposing force may be sufficient to reduce deviation of
the drill bit from the determined drill trajectory, especially when
such trajectory is at an oblique angle to the anatomical feature
being engaged.
[0012] The above-described system and its various features may be
associated with a variety of related procedures or processes,
collectively referred to herein as methods. One such method
involves guiding a drill during robot-assisted surgery on an
anatomical feature of a patient, such method including the
determination by suitable computer means of a drill target and an
associated drill trajectory. Thereafter, the end-effector is caused
to move, such as by means of a computer, to a position
corresponding to the determined target and the determined drill
trajectory. At any other point prior to drill advancement during
operations, the depth stop connected to the end-effector may be
manually set at one of a plurality of selectable positions
corresponding to a desired depth of advancement of the drill
relative to the anatomical feature. In this manner, the drill is
limited from penetrating the anatomical feature beyond the desired
depth set manually by the depth stop.
[0013] In another possible method hereunder, the depth stop is
displaced relative to visually perceptible indicia corresponding to
graduated depths of advancement of the drill associated with the
system. Once a suitable location of the depth stop is determined by
visual perception, the depth stop may be secured at a position
corresponding to one of the graduated depths indicated on the
indicia. The steps of displacing and securing the depth stop may
involve actuating a spring-biased trigger to disengage the depth
stop from a first position, longitudinally sliding the depth stop
relative to the visually perceptible indicia to a second position
corresponding to the desired position of the depth stop, and then
releasing the trigger to re-engage the depth stop at the desired
position.
[0014] Other methods and related devices and systems, and
corresponding methods and computer program products according to
embodiments will be or become apparent to one with skill in the art
upon review of the following drawings and detailed description. It
is intended that all such devices and systems, and corresponding
methods and computer program products be included within this
description, be within the scope of the present disclosure, and be
protected by the accompanying claims. Moreover, it is intended that
all embodiments disclosed herein can be implemented separately or
combined in any way and/or combination.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings, which are included to provide a
further understanding of the disclosure and are incorporated in a
constitute a part of this application, illustrate certain
non-limiting embodiments of inventive concepts. In the
drawings:
[0016] FIG. 1A is an overhead view of an arrangement for locations
of a robotic system, patient, surgeon, and other medical personnel
during a surgical procedure, according to some embodiments;
[0017] FIG. 1B is an overhead view of an alternate arrangement for
locations of a robotic system, patient, surgeon, and other medical
personnel during a cranial surgical procedure, according to some
embodiments;
[0018] FIG. 2 illustrates a robotic system including positioning of
the surgical robot and a camera relative to the patient according
to some embodiments;
[0019] FIG. 3 is a flowchart diagram illustrating
computer-implemented operations for determining a position and
orientation of an anatomical feature of a patient with respect to a
robot arm of a surgical robot, according to some embodiments;
[0020] FIG. 4 is a diagram illustrating processing of data for
determining a position and orientation of an anatomical feature of
a patient with respect to a robot arm of a surgical robot,
according to some embodiments;
[0021] FIGS. 5A-5C illustrate a system for registering an
anatomical feature of a patient using a computerized tomography
(CT) localizer, a frame reference array (FRA), and a dynamic
reference base (DRB), according to some embodiments;
[0022] FIGS. 6A and 6B illustrate a system for registering an
anatomical feature of a patient using fluoroscopy (fluoro) imaging,
according to some embodiments;
[0023] FIG. 7 illustrates a system for registering an anatomical
feature of a patient using an intraoperative CT fixture (ICT) and a
DRB, according to some embodiments;
[0024] FIGS. 8A and 8B illustrate systems for registering an
anatomical feature of a patient using a DRB and an X-ray cone beam
imaging device, according to some embodiments;
[0025] FIG. 9 illustrates a system for registering an anatomical
feature of a patient using a navigated probe and fiducials for
point-to-point mapping of the anatomical feature, according to some
embodiments;
[0026] FIG. 10 illustrates a two-dimensional visualization of an
adjustment range for a centerpoint-arc mechanism, according to some
embodiments;
[0027] FIG. 11 illustrates a two-dimensional visualization of
virtual point rotation mechanism, according to some
embodiments;
[0028] FIG. 12 is an isometric view of one possible implementation
of an end-effector according to the present disclosure;
[0029] FIG. 13 is an isometric view of another possible
implementation of an end-effector of the present disclosure;
[0030] FIG. 14 is a partial cutaway, isometric view of still
another possible implementation of an end-effector according to the
present disclosure;
[0031] FIG. 15 is a bottom angle isometric view of yet another
possible implementation of an end-effector according to the present
disclosure;
[0032] FIG. 16 is an isometric view of one possible tool stop for
use with an end-effector according to the present disclosure;
[0033] FIGS. 17 and 18 are top plan views of one possible
implementation of a tool insert locking mechanism of an
end-effector according to the present disclosure;
[0034] FIGS. 19 and 20 are top plan views of the tool stop of FIG.
16, showing open and closed positions, respectively;
[0035] FIG. 21 is a side, elevational view of another
implementation of the robot system disclosed herein, including an
end-effector and associated drill guide;
[0036] FIG. 22 is a close-up, side-elevational view of the drill
guide of FIG. 21;
[0037] FIG. 23 is a front elevational view of the drill guide of
FIGS. 21-22;
[0038] FIG. 24 is a cross sectional view of the drill guide of
FIGS. 21-23 taken along the line of A-A of FIG. 23; and
[0039] FIG. 25 is an exploded, side-elevational view of the drill
guide of FIGS. 21-24.
DETAILED DESCRIPTION
[0040] It is to be understood that the present disclosure is not
limited in its application to the details of construction and the
arrangement of components set forth in the description herein or
illustrated in the drawings. The teachings of the present
disclosure may be used and practiced in other embodiments and
practiced or carried out in various ways. Also, it is to be
understood that the phraseology and terminology used herein is for
the purpose of description and should not be regarded as limiting.
The use of "including," "comprising," or "having" and variations
thereof herein is meant to encompass the items listed thereafter
and equivalents thereof as well as additional items. Unless
specified or limited otherwise, the terms "mounted," "connected,"
"supported," and "coupled" and variations thereof are used broadly
and encompass both direct and indirect mountings, connections,
supports, and couplings. Further, "connected" and "coupled" are not
restricted to physical or mechanical connections or couplings.
[0041] The following discussion is presented to enable a person
skilled in the art to make and use embodiments of the present
disclosure. Various modifications to the illustrated embodiments
will be readily apparent to those skilled in the art, and the
principles herein can be applied to other embodiments and
applications without departing from embodiments of the present
disclosure. Thus, the embodiments are not intended to be limited to
embodiments shown, but are to be accorded the widest scope
consistent with the principles and features disclosed herein. The
following detailed description is to be read with reference to the
figures, in which like elements in different figures have like
reference numerals. The figures, which are not necessarily to
scale, depict selected embodiments and are not intended to limit
the scope of the embodiments. Skilled artisans will recognize the
examples provided herein have many useful alternatives and fall
within the scope of the embodiments.
[0042] According to some other embodiments, systems for
neuronavigation registration and robotic trajectory guidance, and
related methods and devices are disclosed. In some embodiments, a
first image having an anatomical feature of a patient, a
registration fixture that is fixed with respect to the anatomical
feature of the patient, and a first plurality of fiducial markers
that are fixed with respect to the registration fixture is
analyzed, and a position is determined for each fiducial marker of
the first plurality of fiducial markers. Next, based on the
determined positions of the first plurality of fiducial markers, a
position and orientation of the registration fixture with respect
to the anatomical feature is determined. A data frame comprising a
second plurality of tracking markers that are fixed with respect to
the registration fixture is also analyzed, and a position is
determined for each tracking marker of the second plurality of
tracking markers. Based on the determined positions of the second
plurality of tracking markers, a position and orientation of the
registration fixture with respect to a robot arm of a surgical
robot is determined. Based on the determined position and
orientation of the registration fixture with respect to the
anatomical feature and the determined position and orientation of
the registration fixture with respect to the robot arm, a position
and orientation of the anatomical feature with respect to the robot
arm is determined, which allows the robot arm to be controlled
based on the determined position and orientation of the anatomical
feature with respect to the robot arm.
[0043] Advantages of this and other embodiments include the ability
to combine neuronavigation and robotic trajectory alignment into
one system, with support for a wide variety of different
registration hardware and methods. For example, as will be
described in detail below, embodiments may support both
computerized tomography (CT) and fluoroscopy (fluoro) registration
techniques, and may utilize frame-based and/or frameless surgical
arrangements. Moreover, in many embodiments, if an initial (e.g.
preoperative) registration is compromised due to movement of a
registration fixture, registration of the registration fixture (and
of the anatomical feature by extension) can be re-established
intraoperatively without suspending surgery and re-capturing
preoperative images.
[0044] Referring now to the drawings, FIG. 1A illustrates a
surgical robot system 100 in accordance with an embodiment.
Surgical robot system 100 may include, for example, a surgical
robot 102, one or more robot arms 104, a base 106, a display 110,
an end-effector 112, for example, including a guide tube 114, and
one or more tracking markers 118. The robot arm 104 may be movable
along and/or about an axis relative to the base 106, responsive to
input from a user, commands received from a processing device, or
other methods. The surgical robot system 100 may include a patient
tracking device 116 also including one or more tracking markers
118, which is adapted to be secured directly to the patient 210
(e.g., to a bone of the patient 210). As will be discussed in
greater detail below, the tracking markers 118 may be secured to or
may be part of a stereotactic frame that is fixed with respect to
an anatomical feature of the patient 210. The stereotactic frame
may also be secured to a fixture to prevent movement of the patient
210 during surgery.
[0045] According to an alternative embodiment, FIG. 1B is an
overhead view of an alternate arrangement for locations of a
robotic system 100, patient 210, surgeon 120, and other medical
personnel during a cranial surgical procedure. During a cranial
procedure, for example, the robot 102 may be positioned behind the
head 128 of the patient 210. The robot arm 104 of the robot 102 has
an end-effector 112 that may hold a surgical instrument 108 during
the procedure. In this example, a stereotactic frame 134 is fixed
with respect to the patient's head 128, and the patient 210 and/or
stereotactic frame 134 may also be secured to a patient base 211 to
prevent movement of the patient's head 128 with respect to the
patient base 211. In addition, the patient 210, the stereotactic
frame 134 and/or or the patient base 211 may be secured to the
robot base 106, such as via an auxiliary arm 107, to prevent
relative movement of the patient 210 with respect to components of
the robot 102 during surgery. Different devices may be positioned
with respect to the patient's head 128 and/or patient base 211 as
desired to facilitate the procedure, such as an intra-operative CT
device 130, an anesthesiology station 132, a scrub station 136, a
neuro-modulation station 138, and/or one or more remote pendants
140 for controlling the robot 102 and/or other devices or systems
during the procedure.
[0046] The surgical robot system 100 in the examples of FIGS. 1A
and/or 1B may also use a sensor, such as a camera 200, for example,
positioned on a camera stand 202. The camera stand 202 can have any
suitable configuration to move, orient, and support the camera 200
in a desired position. The camera 200 may include any suitable
camera or cameras, such as one or more cameras (e.g., bifocal or
stereophotogrammetric cameras), able to identify, for example,
active or passive tracking markers 118 (shown as part of patient
tracking device 116 in FIG. 2) in a given measurement volume
viewable from the perspective of the camera 200. In this example,
the camera 200 may scan the given measurement volume and detect the
light that comes from the tracking markers 118 in order to identify
and determine the position of the tracking markers 118 in
three-dimensions. For example, active tracking markers 118 may
include infrared-emitting markers that are activated by an
electrical signal (e.g., infrared light emitting diodes (LEDs)),
and/or passive tracking markers 118 may include retro-reflective
markers that reflect infrared or other light (e.g., they reflect
incoming IR radiation into the direction of the incoming light),
for example, emitted by illuminators on the camera 200 or other
suitable sensor or other device.
[0047] In many surgical procedures, one or more targets of surgical
interest, such as targets within the brain for example, are
localized to an external reference frame. For example, stereotactic
neurosurgery may use an externally mounted stereotactic frame that
facilitates patient localization and implant insertion via a frame
mounted arc. Neuronavigation is used to register, e.g., map,
targets within the brain based on pre-operative or intraoperative
imaging. Using this pre-operative or intraoperative imaging, links
and associations can be made between the imaging and the actual
anatomical structures in a surgical environment, and these links
and associations can be utilized by robotic trajectory systems
during surgery.
[0048] According to some embodiments, various software and hardware
elements may be combined to create a system that can be used to
plan, register, place and verify the location of an instrument or
implant in the brain. These systems may integrate a surgical robot,
such as the surgical robot 102 of FIGS. 1A and/or 1B, and may
employ a surgical navigation system and planning software to
program and control the surgical robot. In addition or
alternatively, the surgical robot 102 may be remotely controlled,
such as by nonsterile personnel.
[0049] The robot 102 may be positioned near or next to patient 210,
and it will be appreciated that the robot 102 can be positioned at
any suitable location near the patient 210 depending on the area of
the patient 210 undergoing the operation. The camera 200 may be
separated from the surgical robot system 100 and positioned near or
next to patient 210 as well, in any suitable position that allows
the camera 200 to have a direct visual line of sight to the
surgical field 208. In the configuration shown, the surgeon 120 may
be positioned across from the robot 102, but is still able to
manipulate the end-effector 112 and the display 110. A surgical
assistant 126 may be positioned across from the surgeon 120 again
with access to both the end-effector 112 and the display 110. If
desired, the locations of the surgeon 120 and the assistant 126 may
be reversed. The traditional areas for the anesthesiologist 122 and
the nurse or scrub tech 124 may remain unimpeded by the locations
of the robot 102 and camera 200.
[0050] With respect to the other components of the robot 102, the
display 110 can be attached to the surgical robot 102 and in other
embodiments, the display 110 can be detached from surgical robot
102, either within a surgical room with the surgical robot 102, or
in a remote location. The end-effector 112 may be coupled to the
robot arm 104 and controlled by at least one motor. In some
embodiments, end-effector 112 can comprise a guide tube 114, which
is able to receive and orient a surgical instrument 108 used to
perform surgery on the patient 210. As used herein, the term
"end-effector" is used interchangeably with the terms
"end-effectuator" and "effectuator element." Although generally
shown with a guide tube 114, it will be appreciated that the
end-effector 112 may be replaced with any suitable instrumentation
suitable for use in surgery. In some embodiments, end-effector 112
can comprise any known structure for effecting the movement of the
surgical instrument 108 in a desired manner.
[0051] The surgical robot 102 is able to control the translation
and orientation of the end-effector 112. The robot 102 is able to
move end-effector 112 along x-, y-, and z-axes, for example. The
end-effector 112 can be configured for selective rotation about one
or more of the x-, y-, and z-axis such that one or more of the
Euler Angles (e.g., roll, pitch, and/or yaw) associated with
end-effector 112 can be selectively controlled. In some
embodiments, selective control of the translation and orientation
of end-effector 112 can permit performance of medical procedures
with significantly improved accuracy compared to conventional
robots that use, for example, a six degree of freedom robot arm
comprising only rotational axes. For example, the surgical robot
system 100 may be used to operate on patient 210, and robot arm 104
can be positioned above the body of patient 210, with end-effector
112 selectively angled relative to the z-axis toward the body of
patient 210.
[0052] In some embodiments, the position of the surgical instrument
108 can be dynamically updated so that surgical robot 102 can be
aware of the location of the surgical instrument 108 at all times
during the procedure. Consequently, in some embodiments, surgical
robot 102 can move the surgical instrument 108 to the desired
position quickly without any further assistance from a physician
(unless the physician so desires). In some further embodiments,
surgical robot 102 can be configured to correct the path of the
surgical instrument 108 if the surgical instrument 108 strays from
the selected, preplanned trajectory. In some embodiments, surgical
robot 102 can be configured to permit stoppage, modification,
and/or manual control of the movement of end-effector 112 and/or
the surgical instrument 108. Thus, in use, in some embodiments, a
physician or other user can operate the system 100, and has the
option to stop, modify, or manually control the autonomous movement
of end-effector 112 and/or the surgical instrument 108. Further
details of surgical robot system 100 including the control and
movement of a surgical instrument 108 by surgical robot 102 can be
found in co-pending U.S. Patent Publication No. 2013/0345718, which
is incorporated herein by reference in its entirety.
[0053] As will be described in greater detail below, the surgical
robot system 100 can comprise one or more tracking markers
configured to track the movement of robot arm 104, end-effector
112, patient 210, and/or the surgical instrument 108 in three
dimensions. In some embodiments, a plurality of tracking markers
can be mounted (or otherwise secured) thereon to an outer surface
of the robot 102, such as, for example and without limitation, on
base 106 of robot 102, on robot arm 104, and/or on the end-effector
112. In some embodiments, such as the embodiment of FIG. 3 below,
for example, one or more tracking markers can be mounted or
otherwise secured to the end-effector 112. One or more tracking
markers can further be mounted (or otherwise secured) to the
patient 210. In some embodiments, the plurality of tracking markers
can be positioned on the patient 210 spaced apart from the surgical
field 208 to reduce the likelihood of being obscured by the
surgeon, surgical tools, or other parts of the robot 102. Further,
one or more tracking markers can be further mounted (or otherwise
secured) to the surgical instruments 108 (e.g., a screw driver,
dilator, implant inserter, or the like). Thus, the tracking markers
enable each of the marked objects (e.g., the end-effector 112, the
patient 210, and the surgical instruments 108) to be tracked by the
surgical robot system 100. In some embodiments, system 100 can use
tracking information collected from each of the marked objects to
calculate the orientation and location, for example, of the
end-effector 112, the surgical instrument 108 (e.g., positioned in
the tube 114 of the end-effector 112), and the relative position of
the patient 210. Further details of surgical robot system 100
including the control, movement and tracking of surgical robot 102
and of a surgical instrument 108 can be found in U.S. Patent
Publication No. 2016/0242849, which is incorporated herein by
reference in its entirety.
[0054] In some embodiments, pre-operative imaging may be used to
identify the anatomy to be targeted in the procedure. If desired by
the surgeon the planning package will allow for the definition of a
reformatted coordinate system. This reformatted coordinate system
will have coordinate axes anchored to specific anatomical
landmarks, such as the anterior commissure (AC) and posterior
commissure (PC) for neurosurgery procedures. In some embodiments,
multiple pre-operative exam images (e.g., CT or magnetic resonance
(MR) images) may be co-registered such that it is possible to
transform coordinates of any given point on the anatomy to the
corresponding point on all other pre-operative exam images.
[0055] As used herein, registration is the process of determining
the coordinate transformations from one coordinate system to
another. For example, in the co-registration of preoperative
images, co-registering a CT scan to an MR scan means that it is
possible to transform the coordinates of an anatomical point from
the CT scan to the corresponding anatomical location in the MR
scan. It may also be advantageous to register at least one exam
image coordinate system to the coordinate system of a common
registration fixture, such as a dynamic reference base (DRB), which
may allow the camera 200 to keep track of the position of the
patient in the camera space in real-time so that any intraoperative
movement of an anatomical point on the patient in the room can be
detected by the robot system 100 and accounted for by compensatory
movement of the surgical robot 102.
[0056] FIG. 3 is a flowchart diagram illustrating
computer-implemented operations 300 for determining a position and
orientation of an anatomical feature of a patient with respect to a
robot arm of a surgical robot, according to some embodiments. The
operations 300 may include receiving a first image volume, such as
a CT scan, from a preoperative image capture device at a first time
(Block 302). The first image volume includes an anatomical feature
of a patient and at least a portion of a registration fixture that
is fixed with respect to the anatomical feature of the patient. The
registration fixture includes a first plurality of fiducial markers
that are fixed with respect to the registration fixture. The
operations 300 further include determining, for each fiducial
marker of the first plurality of fiducial markers, a position of
the fiducial marker relative to the first image volume (Block 304).
The operations 300 further include, determining, based on the
determined positions of the first plurality of fiducial markers,
positions of an array of tracking markers on the registration
fixture (fiducial registration array or FRA) with respect to the
anatomical feature (Block 306).
[0057] The operations 300 may further include receiving a tracking
data frame from an intraoperative tracking device comprising a
plurality of tracking cameras at a second time that is later than
the first time (Block 308). The tracking frame includes positions
of a plurality of tracking markers that are fixed with respect to
the registration fixture (FRA) and a plurality of tracking markers
that are fixed with respect to the robot. The operations 300
further include determining, for based on the positions of tracking
markers of the registration fixture, a position and orientation of
the anatomical feature with respect to the tracking cameras (Block
310). The operations 300 further include determining, based on the
determined positions of the plurality of tracking markers on the
robot, a position and orientation of the robot arm of a surgical
robot with respect to the tracking cameras (Block 312).
[0058] The operations 300 further include determining, based on the
determined position and orientation of the anatomical feature with
respect to the tracking cameras and the determined position and
orientation of the robot arm with respect to the tracking cameras,
a position and orientation of the anatomical feature with respect
to the robot arm (Block 314). The operations 300 further include
controlling movement of the robot arm with respect to the
anatomical feature, e.g., along and/or rotationally about one or
more defined axis, based on the determined position and orientation
of the anatomical feature with respect to the robot arm (Block
316).
[0059] FIG. 4 is a diagram illustrating a data flow 400 for a
multiple coordinate transformation system, to enable determining a
position and orientation of an anatomical feature of a patient with
respect to a robot arm of a surgical robot, according to some
embodiments. In this example, data from a plurality of exam image
spaces 402, based on a plurality of exam images, may be transformed
and combined into a common exam image space 404. The data from the
common exam image space 404 and data from a verification image
space 406, based on a verification image, may be transformed and
combined into a registration image space 408. Data from the
registration image space 408 may be transformed into patient
fiducial coordinates 410, which is transformed into coordinates for
a DRB 412. A tracking camera 414 may detect movement of the DRB 412
(represented by DRB 412') and may also detect a location of a probe
tracker 416 to track coordinates of the DRB 412 over time. A
robotic arm tracker 418 determines coordinates for the robot arm
based on transformation data from a Robotics Planning System (RPS)
space 420 or similar modeling system, and/or transformation data
from the tracking camera 414.
[0060] It should be understood that these and other features may be
used and combined in different ways to achieve registration of
image space, i.e., coordinates from image volume, into tracking
space, i.e., coordinates for use by the surgical robot in
real-time. As will be discussed in detail below, these features may
include fiducial-based registration such as stereotactic frames
with CT localizer, preoperative CT or MRI registered using
intraoperative fluoroscopy, calibrated scanner registration where
any acquired scan's coordinates are pre-calibrated relative to the
tracking space, and/or surface registration using a tracked probe,
for example.
[0061] In one example, FIGS. 5A-5C illustrate a system 500 for
registering an anatomical feature of a patient. In this example,
the stereotactic frame base 530 is fixed to an anatomical feature
528 of patient, e.g., the patient's head. As shown by FIG. 5A, the
stereotactic frame base 530 may be affixed to the patient's head
528 prior to registration using pins clamping the skull or other
method. The stereotactic frame base 530 may act as both a fixation
platform, for holding the patient's head 528 in a fixed position,
and registration and tracking platform, for alternatingly holding
the CT localizer 536 or the FRA fixture 534. The CT localizer 536
includes a plurality of fiducial markers 532 (e.g., N-pattern
radio-opaque rods or other fiducials), which are automatically
detected in the image space using image processing. Due to the
precise attachment mechanism of the CT localizer 536 to the base
530, these fiducial markers 532 are in known space relative to the
stereotactic frame base 530. A 3D CT scan of the patient with CT
localizer 536 attached is taken, with an image volume that includes
both the patient's head 528 and the fiducial markers 532 of the CT
localizer 536. This registration image can be taken
intraoperatively or preoperatively, either in the operating room or
in radiology, for example. The captured 3D image dataset is stored
to computer memory.
[0062] As shown by FIG. 5B, after the registration image is
captured, the CT localizer 536 is removed from the stereotactic
frame base 530 and the frame reference array fixture 534 is
attached to the stereotactic frame base 530. The stereotactic frame
base 530 remains fixed to the patient's head 528, however, and is
used to secure the patient during surgery, and serves as the
attachment point of a frame reference array fixture 534. The frame
reference array fixture 534 includes a frame reference array (FRA),
which is a rigid array of three or more tracked markers 539, which
may be the primary reference for optical tracking. By positioning
the tracked markers 539 of the FRA in a fixed, known location and
orientation relative to the stereotactic frame base 530, the
position and orientation of the patient's head 528 may be tracked
in real time. Mount points on the FRA fixture 534 and stereotactic
frame base 530 may be designed such that the FRA fixture 534
attaches reproducibly to the stereotactic frame base 530 with
minimal (i.e., submillimetric) variability. These mount points on
the stereotactic frame base 530 can be the same mount points used
by the CT localizer 536, which is removed after the scan has been
taken. An auxiliary arm (such as auxiliary arm 107 of FIG. 1B, for
example) or other attachment mechanism can also be used to securely
affix the patient to the robot base to ensure that the robot base
is not allowed to move relative to the patient.
[0063] As shown by FIG. 5C, a dynamic reference base (DRB) 540 may
also be attached to the stereotactic frame base 530. The DRB 540 in
this example includes a rigid array of three or more tracked
markers 542. In this example, the DRB 540 and/or other tracked
markers may be attached to the stereotactic frame base 530 and/or
to directly to the patient's head 528 using auxiliary mounting arms
541, pins, or other attachment mechanisms. Unlike the FRA fixture
534, which mounts in only one way for unambiguous localization of
the stereotactic frame base 530, the DRB 540 in general may be
attached as needed for allowing unhindered surgical and equipment
access. Once the DRB 540 and FRA fixture 534 are attached,
registration, which was initially related to the tracking markers
539 of the FRA, can be optionally transferred or related to the
tracking markers 542 of the DRB 540. For example, if any part of
the FRA fixture 534 blocks surgical access, the surgeon may remove
the FRA fixture 534 and navigate using only the DRB 540. However,
if the FRA fixture 534 is not in the way of the surgery, the
surgeon could opt to navigate from the FRA markers 539, without
using a DRB 540, or may navigate using both the FRA markers 539 and
the DRB 540. In this example, the FRA fixture 534 and/or DRB 540
uses optical markers, the tracked positions of which are in known
locations relative to the stereotactic frame base 530, similar to
the CT localizer 536, but it should be understood that many other
additional and/or alternative techniques may be used.
[0064] FIGS. 6A and 6B illustrate a system 600 for registering an
anatomical feature of a patient using fluoroscopy (fluoro) imaging,
according to some embodiments. In this embodiment, image space is
registered to tracking space using multiple intraoperative
fluoroscopy (fluoro) images taken using a tracked registration
fixture 644. The anatomical feature of the patient (e.g., the
patient's head 628) is positioned and rigidly affixed in a clamping
apparatus 643 in a static position for the remainder of the
procedure. The clamping apparatus 643 for rigid patient fixation
can be a three-pin fixation system such as a Mayfield clamp, a
stereotactic frame base attached to the surgical table, or another
fixation method, as desired. The clamping apparatus 643 may also
function as a support structure for a patient tracking array or DRB
640 as well. The DRB may be attached to the clamping apparatus
using auxiliary mounting arms 641 or other means.
[0065] Once the patient is positioned, the fluoro fixture 644 is
attached the fluoro unit's x-ray collecting image intensifier (not
shown) and secured by tightening clamping feet 632. The fluoro
fixture 644 contains fiducial markers (e.g., metal spheres laid out
across two planes in this example, not shown) that are visible on
2D fluoro images captured by the fluoro image capture device and
can be used to calculate the location of the x-ray source relative
to the image intensifier, which is typically about 1 meter away
contralateral to the patient, using a standard pinhole camera
model. Detection of the metal spheres in the fluoro image captured
by the fluoro image capture device also enables the software to
de-warp the fluoro image (i.e., to remove pincushion and
s-distortion). Additionally, the fluoro fixture 644 contains 3 or
more tracking markers 646 for determining the location and
orientation of the fluoro fixture 644 in tracking space. In some
embodiments, software can project vectors through a CT image
volume, based on a previously captured CT image, to generate
synthetic images based on contrast levels in the CT image that
appear similar to the actual fluoro images (i.e., digitally
reconstructed radiographs (DRRs)). By iterating through theoretical
positions of the fluoro beam until the DRRs match the actual fluoro
shots, a match can be found between fluoro image and DRR in two or
more perspectives, and based on this match, the location of the
patient's head 628 relative to the x-ray source and detector is
calculated. Because the tracking markers 646 on the fluoro fixture
644 track the position of the image intensifier and the position of
the x-ray source relative to the image intensifier is calculated
from metal fiducials on the fluoro fixture 644 projected on 2D
images, the position of the x-ray source and detector in tracking
space are known and the system is able to achieve image-to-tracking
registration.
[0066] As shown by FIGS. 6A and 6B, two or more shots are taken of
the head 628 of the patient by the fluoro image capture device from
two different perspectives while tracking the array markers 642 of
the DRB 640, which is fixed to the registration fixture 630 via a
mounting arm 641, and tracking markers 646 on the fluoro fixture
644. Based on the tracking data and fluoro data, an algorithm
computes the location of the head 628 or other anatomical feature
relative to the tracking space for the procedure. Through
image-to-tracking registration, the location of any tracked tool in
the image volume space can be calculated.
[0067] For example, in one embodiment, a first fluoro image taken
from a first fluoro perspective can be compared to a first DRR
constructed from a first perspective through a CT image volume, and
a second fluoro image taken from a second fluoro perspective can be
compared to a second DRR constructed from a second perspective
through the same CT image volume. Based on the comparisons, it may
be determined that the first DRR is substantially equivalent to the
first fluoro image with respect to the projected view of the
anatomical feature, and that the second DRR is substantially
equivalent to the second fluoro image with respect to the projected
view of the anatomical feature. Equivalency confirms that the
position and orientation of the x-ray path from emitter to
collector on the actual fluoro machine as tracked in camera space
matches the position and orientation of the x-ray path from emitter
to collector as specified when generating the DRRs in CT space, and
therefore registration of tracking space to CT space is
achieved.
[0068] FIG. 7 illustrates a system 700 for registering an
anatomical feature of a patient using an intraoperative CT fixture
(ICT) and a DRB, according to some embodiments. As shown in FIG. 7,
in one application, a fiducial-based image-to-tracking registration
can be utilized that uses an intraoperative CT fixture (ICT) 750
having a plurality of tracking markers 751 and radio-opaque
fiducial reference markers 732 to register the CT space to the
tracking space. After stabilizing the anatomical feature 728 (e.g.,
the patient's head) using clamping apparatus 730 such as a
three-pin Mayfield frame and/or stereotactic frame, the surgeon
will affix the ICT 750 to the anatomical feature 728, DRB 740, or
clamping apparatus 730, so that it is in a static position relative
to the tracking markers 742 of the DRB 740, which may be held in
place by mounting arm 741 or other rigid means. A CT scan is
captured that encompasses the fiducial reference markers 732 of the
ICT 750 while also capturing relevant anatomy of the anatomical
feature 728. Once the CT scan is loaded in the software, the system
auto-identifies (through image processing) locations of the
fiducial reference markers 732 of the ICT within the CT volume,
which are in a fixed position relative to the tracking markers of
the ICT 750, providing image-to-tracking registration. This
registration, which was initially based on the tracking markers 751
of the ICT 750, is then related to or transferred to the tracking
markers 742 of the DRB 740, and the ICT 750 may then be
removed.
[0069] FIG. 8A illustrates a system 800 for registering an
anatomical feature of a patient using a DRB and an X-ray cone beam
imaging device, according to some embodiments. An intraoperative
scanner 852, such as an X-ray machine or other scanning device, may
have a tracking array 854 with tracking markers 855, mounted
thereon for registration. Based on the fixed, known position of the
tracking array 854 on the scanning device, the system may be
calibrated to directly map (register) the tracking space to the
image space of any scan acquired by the system. Once registration
is achieved, the registration, which is initially based on the
tracking markers 855 (e.g. gantry markers) of the scanner's array
854, is related or transferred to the tracking markers 842 of a DRB
840, which may be fixed to a clamping fixture 830 holding the
patient's head 828 by a mounting arm 841 or other rigid means.
After transferring registration, the markers on the scanner are no
longer used and can be removed, deactivated or covered if desired.
Registering the tracking space to any image acquired by a scanner
in this way may avoid the need for fiducials or other reference
markers in the image space in some embodiments.
[0070] FIG. 8B illustrates an alternative system 800' that uses a
portable intraoperative scanner, referred to herein as a C-arm
scanner 853. In this example, the C-arm scanner 853 includes a
c-shaped arm 856 coupled to a movable base 858 to allow the C-arm
scanner 853 to be moved into place and removed as needed, without
interfering with other aspects of the surgery. The arm 856 is
positioned around the patient's head 828 intraoperatively, and the
arm 856 is rotated and/or translated with respect to the patient's
head 828 to capture the X-ray or other type of scan that to achieve
registration, at which point the C-arm scanner 853 may be removed
from the patient.
[0071] Another registration method for an anatomical feature of a
patient, e.g., a patient's head, may be to use a surface contour
map of the anatomical feature, according to some embodiments. A
surface contour map may be constructed using a navigated or tracked
probe, or other measuring or sensing device, such as a laser
pointer, 3D camera, etc. For example, a surgeon may drag or
sequentially touch points on the surface of the head with the
navigated probe to capture the surface across unique protrusions,
such as zygomatic bones, superciliary arches, bridge of nose,
eyebrows, etc. The system then compares the resulting surface
contours to contours detected from the CT and/or MR images, seeking
the location and orientation of contour that provides the closest
match. To account for movement of the patient and to ensure that
all contour points are taken relative to the same anatomical
feature, each contour point is related to tracking markers on a DRB
on the patient at the time it is recorded. Since the location of
the contour map is known in tracking space from the tracked probe
and tracked DRB, tracking-to-image registration is obtained once
the corresponding contour is found in image space.
[0072] FIG. 9 illustrates a system 900 for registering an
anatomical feature of a patient using a navigated or tracked probe
and fiducials for point-to-point mapping of the anatomical feature
928 (e.g., a patient's head), according to some embodiments.
Software would instruct the user to point with a tracked probe to a
series of anatomical landmark points that can be found in the CT or
MR image. When the user points to the landmark indicated by
software, the system captures a frame of tracking data with the
tracked locations of tracking markers on the probe and on the DRB.
From the tracked locations of markers on the probe, the coordinates
of the tip of the probe are calculated and related to the locations
of markers on the DRB. Once 3 or more points are found in both
spaces, tracking-to-image registration is achieved. As an
alternative to pointing to natural anatomical landmarks, fiducials
954 (i.e., fiducial markers), such as sticker fiducials or metal
fiducials, may be used. The surgeon will attach the fiducials 954
to the patient, which are constructed of material that is opaque on
imaging, for example containing metal if used with CT or Vitamin E
if used with MR. Imaging (CT or MR) will occur after placing the
fiducials 954. The surgeon or user will then manually find the
coordinates of the fiducials in the image volume, or the software
will find them automatically with image processing. After attaching
a DRB 940 with tracking markers 942 to the patient through a
mounting arm 941 connected to a clamping apparatus 930 or other
rigid means, the surgeon or user may also locate the fiducials 954
in physical space relative to the DRB 940 by touching the fiducials
954 with a tracked probe while simultaneously recording tracking
markers on the probe (not shown) and on the DRB 940. Registration
is achieved because the coordinates of the same points are known in
the image space and the tracking space.
[0073] One use for the embodiments described herein is to plan
trajectories and to control a robot to move into a desired
trajectory, after which the surgeon will place implants such as
electrodes through a guide tube held by the robot. Additional
functionalities include exporting coordinates used with existing
stereotactic frames, such as a Leksell frame, which uses five
coordinates: X, Y, Z, Ring Angle and Arc Angle. These five
coordinates are established using the target and trajectory
identified in the planning stage relative to the image space and
knowing the position and orientation of the ring and arc relative
to the stereotactic frame base or other registration fixture.
[0074] As shown in FIG. 10, stereotactic frames allow a target
location 1058 of an anatomical feature 1028 (e.g., a patient's
head) to be treated as the center of a sphere and the trajectory
can pivot about the target location 1058. The trajectory to the
target location 1058 is adjusted by the ring and arc angles of the
stereotactic frame (e.g., a Leksell frame). These coordinates may
be set manually, and the stereotactic frame may be used as a backup
or as a redundant system in case the robot fails or cannot be
tracked or registered successfully. The linear x,y,z offsets to the
center point (i.e., target location 1058) are adjusted via the
mechanisms of the frame. A cone 1060 is centered around the target
location 1058, and shows the adjustment zone that can be achieved
by modifying the ring and arc angles of the Leksell or other type
of frame. This figure illustrates that a stereotactic frame with
ring and arc adjustments is well suited for reaching a fixed target
location from a range of angles while changing the entry point into
the skull.
[0075] FIG. 11 illustrates a two-dimensional visualization of
virtual point rotation mechanism, according to some embodiments. In
this embodiment, the robotic arm is able to create a different type
of point-rotation functionality that enables a new movement mode
that is not easily achievable with a 5-axis mechanical frame, but
that may be achieved using the embodiments described herein.
Through coordinated control of the robot's axes using the
registration techniques described herein, this mode allows the user
to pivot the robot's guide tube about any fixed point in space. For
example, the robot may pivot about the entry point 1162 into the
anatomical feature 1128 (e.g., a patient's head). This entry point
pivoting is advantageous as it allows the user to make a smaller
burr hole without limiting their ability to adjust the target
location 1164 intraoperatively. The cone 1160 represents the range
of trajectories that may be reachable through a single entry hole.
Additionally, entry point pivoting is advantageous as it allows the
user to reach two different target locations 1164 and 1166 through
the same small entry burr hole. Alternately, the robot may pivot
about a target point (e.g., location 1058 shown in FIG. 10) within
the skull to reach the target location from different angles or
trajectories, as illustrated in FIG. 10. Such interior pivoting
robotically has the same advantages as a stereotactic frame as it
allows the user to approach the same target location 1058 from
multiple approaches, such as when irradiating a tumor or when
adjusting a path so that critical structures such as blood vessels
or nerves will not be crossed when reaching targets beyond them.
Unlike a stereotactic frame, which relies on fixed ring and arc
articulations to keep a target/pivot point fixed, the robot adjusts
the pivot point through controlled activation of axes and the robot
can therefore dynamically adjust its pivot point and switch as
needed between the modes illustrated in FIGS. 10 and 11.
[0076] Following the insertion of implants or instrumentation using
the robot or ring and arc fixture, these and other embodiments may
allow for implant locations to be verified using intraoperative
imaging. Placement accuracy of the instrument or implant relative
to the planned trajectory can be qualitatively and/or
quantitatively shown to the user. One option for comparing planned
to placed position is to merge a postoperative verification CT
image to any of the preoperative images. Once pre- and
post-operative images are merged and plan is shown overlaid, the
shadow of the implant on postop CT can be compared to the plan to
assess accuracy of placement. Detection of the shadow artifact on
post-op CT can be performed automatically through image processing
and the offset displayed numerically in terms of millimeters offset
at the tip and entry and angular offset along the path. This option
does not require any fiducials to be present in the verification
image since image-to-image registration is performed based on bony
anatomical contours.
[0077] A second option for comparing planned position to the final
placement would utilize intraoperative fluoro with or without an
attached fluoro fixture. Two out-of-plane fluoro images will be
taken and these fluoro images will be matched to DRRs generated
from pre-operative CT or MR as described above for registration.
Unlike some of the registration methods described above, however,
it may be less important for the fluoro images to be tracked
because the key information is where the electrode is located
relative to the anatomy in the fluoro image. The linear or slightly
curved shadow of the electrode would be found on a fluoro image,
and once the DRR corresponding to that fluoro shot is found, this
shadow can be replicated in the CT image volume as a plane or sheet
that is oriented in and out of the ray direction of the fluoro
image and DRR. That is, the system may not know how deep in or out
of the fluoro image plane the electrode lies on a given shot, but
can calculate the plane or sheet of possible locations and
represent this plane or sheet on the 3D volume. In a second fluoro
view, a different plane or sheet can be determined and overlaid on
the 3D image. Where these two planes or sheets intersect on the 3D
image is the detected path of the electrode. The system can
represent this detected path as a graphic on the 3D image volume
and allow the user to reslice the image volume to display this path
and the planned path from whatever perspective is desired, also
allowing automatic or manual calculation of the deviation from
planned to placed position of the electrode. Tracking the fluoro
fixture is unnecessary but may be done to help de-warp the fluoro
images and calculate the location of the x-ray emitter to improve
accuracy of DRR calculation, the rate of convergence when iterating
to find matching DRR and fluoro shots, and placement of
sheets/planes representing the electrode on the 3D scan.
[0078] In this and other examples, it is desirable to maintain
navigation integrity, i.e., to ensure that the registration and
tracking remain accurate throughout the procedure. Two primary
methods to establish and maintain navigation integrity include:
tracking the position of a surveillance marker relative to the
markers on the DRB, and checking landmarks within the images. In
the first method, should this position change due to, for example,
the DRB being bumped, then the system may alert the user of a
possible loss of navigation integrity. In the second method, if a
landmark check shows that the anatomy represented in the displayed
slices on screen does not match the anatomy at which the tip of the
probe points, then the surgeon will also become aware that there is
a loss of navigation integrity. In either method, if using the
registration method of CT localizer and frame reference array
(FRA), the surgeon has the option to re-attach the FRA, which
mounts in only one possible way to the frame base, and to restore
tracking-to-image registration based on the FRA tracking markers
and the stored fiducials from the CT localizer 536. This
registration can then be transferred or related to tracking markers
on a repositioned DRB. Once registration is transferred the FRA can
be removed if desired.
[0079] Referring now to FIGS. 12-18 generally, with reference to
the surgical robot system 100 shown in FIG. 1A, end-effector 112
may be equipped with components, configured, or otherwise include
features so that one end-effector may remain attached to a given
one of robot arms 104 without changing to another end-effector for
multiple different surgical procedures, such as, by way of example
only, Deep Brain Stimulation (DBS), Stereoelectroencephalography
(SEEG), or Endoscopic Navigation and Tumor Biopsy. As discussed
previously, end-effector 112 may be orientable to oppose an
anatomical feature of a patient in the manner so as to be in
operative proximity thereto, and, to be able to receive one or more
surgical tools for operations contemplated on the anatomical
feature proximate to the end-effector 112. Motion and orientation
of end-effector 112 may be accomplished through any of the
navigation, trajectory guidance, or other methodologies discussed
herein or as may be otherwise suitable for the particular
operation.
[0080] End-effector 112 is suitably configured to permit a
plurality of surgical tools 129 to be selectively connectable to
end-effector 112. Thus, for example, a stylet 113 (FIG. 13) may be
selectively attached in order to localize an incision point on an
anatomical feature of a patient, or an electrode driver 115 (FIG.
14) may be selectively attached to the same end-effector 112.
[0081] With reference to the previous discussion of robot surgical
system 100, a processor circuit, as well as memory accessible by
such processor circuit, includes various subroutines and other
machine-readable instructions configured to cause, when executed,
end-effector 112 to move, such as by GPS movement, relative to the
anatomical feature, at predetermined stages of associated surgical
operations, whether pre-operative, intra-operative or
post-operative.
[0082] End-effector 112 includes various components and features to
either prevent or permit end-effector movement depending on whether
and which tools 129, if any, are connected to end-effector 112.
Referring more particularly to FIG. 12, end-effector 112 includes a
tool-insert locking mechanism 117 located on and connected to
proximal surface 119. Tool-insert locking mechanism 117 is
configured so as to secure any selected one of a plurality of
surgical tools, such as the aforesaid stylet 113, electrode driver
115, or any other tools for different surgeries mentioned
previously or as may be contemplated by other applications of this
disclosure. The securement of the tool by tool-insert locking
mechanism 117 is such that, for any of multiple tools capable of
being secured to locking mechanism 117, each such tool is
operatively and suitably secured at the predetermined height, angle
of orientation, and rotational position relative to the anatomical
feature of the patient, such that multiple tools may be secured to
the same end-effector 112 in respective positions appropriate for
the contemplated procedure.
[0083] Another feature of the end-effector 112 is a tool stop 121
located on distal surface 123 of end-effector 112, that is, the
surface generally opposing the patient. Tool stop 121 has a stop
mechanism 125 and a sensor 127 operatively associated therewith, as
seen with reference to FIGS. 16, 19, and 20. Stop mechanism 125 is
mounted to end-effector 112 so as to be selectively movable
relative thereto between an engaged position to prevent any of the
tools from being connected to end-effector 112 and a disengaged
position which permits any of the tools 129 to be selectively
connected to end-effector 112. Sensor 127 may be located on or
within the housing of end-effector 112 at any suitable location
(FIGS. 12, 14, 16) so that sensor 127 detects whether stop
mechanism 125 is in the engaged or disengaged position. Sensor 127
may assume any form suitable for such detection, such as any type
of mechanical switch or any type of magnetic sensor, including Reed
switches, Hall Effect sensors, or other magnetic field detecting
devices. In one possible implementation, sensor 127 has two
portions, a Hall Effect sensor portion (not shown) and a magnetic
portion 131, the two portions moving relative to each other so as
to generate and detect two magnetic fields corresponding to
respective engaged and disengaged position. In the illustrated
implementation, the magnetic portion comprises two rare earth
magnets 131 which move relative to the complementary sensing
portion (not shown) mounted in the housing of end effector 112 in
operative proximity to magnets 131 to detect change in the
associated magnetic field from movement of stop mechanism 125
between engaged and disengaged positions. In this implementation
the Hall effect sensor is bipolar and can detect whether a North
pole or South pole of a magnet opposes the sensor. Magnets 131 are
configured so that the North pole of one magnet faces the path of
the sensor and the South pole of the other magnet faces the path of
the sensor. In this configuration, the sensor senses an increased
signal when it is near one magnet (for example, in disengaged
position), a decreased signal when it is near the other magnet (for
example, in engaged position), and unchanged signal when it is not
in proximity to any magnet. In this implementation, in response to
detection of stop mechanism 125 being in the disengaged position
shown in FIGS. 13 and 19, sensor 127 causes the processor of
surgical robot system 100 to execute suitable instructions to
prevent movement of end-effector 112 relative to the anatomical
feature. Such movement prevention may be appropriate for any number
of reasons, such as when a tool is connected to end-effector 112,
such tool potentially interacting with the anatomical feature of
the patient.
[0084] Another implementation of a sensor 127 for detecting engaged
or disengaged tool stop mechanism 125 could comprise a single
magnet behind the housing (not shown) and two Hall Effect sensors
located where magnets 131 are shown in the preferred embodiment. In
such a configuration, monopolar Hall Effect sensors are suitable
and would be configured so that Sensor 1 detects a signal when the
magnet is in proximity due to the locking mechanism being
disengaged, while Sensor 2 detects a signal when the same magnet is
in proximity due to the locking mechanism being engaged. Neither
sensor would detect a signal when the magnet is between positions
or out of proximity to either sensor. Although a configuration
could be conceived in which a sensor is active for engaged position
and inactive for disengaged position, a configuration with three
signals indicating engaged, disengaged, or transitional is
preferred to ensure correct behavior in case of power failure.
[0085] End-effector 112, tool stop 121, and tool-insert locking
mechanism 117 each have co-axially aligned bores or apertures such
that any selected one of the plurality of surgical tools 129 may be
received through such bores and apertures. In this implementation
end-effector has a bore 133 and tool stop 121 and tool-insert
locking mechanism 117 have respective apertures 135 and 137. Stop
mechanism 125 includes a ring 139 axially aligned with bore 133 and
aperture 135 of tool stop 121. Ring 139 is selectively, manually
rotatable in the directions indicated by arrow A (FIG. 16) so as to
move stop mechanism 125 between the engaged position and the
disengaged position.
[0086] In one possible implementation, the selective rotation of
ring 139 includes features which enable ring 139 to be locked in
either the disengaged or engaged position. So, for example, as
illustrated, a detent mechanism 141 is located on and mounted to
ring 139 in any suitable way to lock ring 139 against certain
rotational movement out of a predetermined position, in this case,
such position being when stop mechanism 125 is in the engaged
position. Although various forms of detent mechanism are
contemplated herein, one suitable arrangement has a manually
accessible head extending circumferentially outwardly from ring 139
and having a male protrusion (not shown) spring-loaded axially
inwardly to engage a corresponding female detent portion (not
shown). Detent mechanism 141, as such, is manually actuatable to
unlock ring 139 from its engaged position to permit ring 139 to be
manually rotated to cause stop mechanism 125 to move from the
engaged position (FIG. 20) to the disengaged position (FIG.
19).
[0087] Tool stop 121 includes a lever arm 143 pivotally mounted
adjacent aperture 135 of tool stop 121 so end of lever arm 143
selectively pivots in the directions indicated by arrow B (FIGS.
16, 19 and 20). Lever arm 143 is operatively connected to stop
mechanism 125, meaning it closes aperture 135 of tool stop 121 in
response to stop mechanism 125 being in the engaged position, as
shown in FIG. 20. Lever arm 143 is also operatively connected so as
to pivot back in direction of arrow B to open aperture 135 in
response to stop mechanism 125 being in the disengaged position. As
such, movement of stop mechanism 125 between engaged and disengaged
positions results in closure or opening of aperture 135,
respectively, by lever arm 143.
[0088] Lever arm 143, in this implementation, is not only pivotally
mounted adjacent aperture 135, but also pivots in parallel with a
distal plane defined at a distal-most point of distal surface 123
of end-effector 112. In this manner, any one of the surgical tools
129, which is attempted to be inserted through bore 133 and
aperture 135, is stopped from being inserted past the distal plane
in which lever arm 143 rotates to close aperture 135.
[0089] Turning now to tool-insert locking mechanism 117 (FIG. 13,
17, 18), a connector 145 is configured to meet with and secure any
one of the surgical tools 129 at their appropriate height, angle of
orientation, and rotational position relative to the anatomical
feature of the patient. In the illustrated implementation,
connector 145 comprises a rotatable flange 147 which has at least
one slot 149 formed therein to receive therethrough a corresponding
tongue 151 associated with a selected one of the plurality of tools
129. So, for example, in FIG. 14, the particular electrode driver
115 has multiple tongues, one of which tongue 151 is shown.
Rotatable flange 147, in some implementations, may comprise a
collar 153, which collar, in turn, has multiple ones of slots 149
radially spaced on a proximally oriented surface 155, as best seen
in FIG. 12. Multiple slots 147 arranged around collar 153 are sized
or otherwise configured so as to receive therethrough corresponding
ones of multiple tongues 151 associated with a selected one of the
plurality of tools 129. Therefore, as seen in FIG. 13, multiple
slots 149 and corresponding tongues 151 may be arranged to permit
securing of a selected one of the plurality of tools 129 only when
selected tool is in the correct, predetermined angle of orientation
and rotational position relative to the anatomical feature of the
patient. Similarly, with regard to the electrode driver shown in
FIG. 14, tongues 151 (one of which is shown in a cutaway of FIG.
14) have been received in radially spaced slots 149 arrayed so that
electrode driver 115 is received at the appropriate angle of
orientation and rotational position.
[0090] Rotatable flange 147 has, in this implementation, a grip 173
to facilitate manual rotation between an open and closed position
as shown in FIGS. 17 and 18, respectively. As seen in FIG. 17,
multiple sets of mating slots 149 and tongues 151 are arranged at
different angular locations, in this case, locations which may be
symmetric about a single diametric chord of a circle but otherwise
radially asymmetric, and at least one of the slots has a different
dimension or extends through a different arc length than other
slots. In this slot-tongue arrangement, and any number of
variations contemplated by this disclosure, there is only one
rotational position of the tool 129 (or adapter 155 discussed
later) to be received in tool-insert locking mechanism 117 when
rotatable flange 147 is in the open position shown in FIG. 17. In
other words, when the user of system 100 moves a selected tool 129
(or tool adapter 155) to a single appropriate rotational position,
corresponding tongues 151 may be received through slots 149. Upon
placement of tongues 151 into slots 149, tongues 151 confront a
base surface 175 within connector 145 of rotatable flange 147. Upon
receiving tongues 151 into slots 149 and having them rest on
underlying base surface 175, dimensions of tongues 151 and slots
149, especially with regard to height relative to rotatable flange
147, are selected so that when rotatable flange 147 is rotated to
the closed position, flange portions 157 are radially translated to
overlie or engage portions of tongues 151, such engagement shown in
FIG. 18 and affixing tool 129 (or adapter 155) received in
connector 145 at the desired, predetermined height, angle of
orientation, and rotational position relative to the anatomical
feature of the patient.
[0091] Tongues 151 described as being associated with tools 129 may
either be directly connected to such tools 129, and/or tongues 151
may be located on and mounted to the above-mentioned adapter 155,
such as that shown in FIGS. 12, 17 and 18, such adapter 155
configured to interconnect at least one of the plurality of
surgical tools 129 with end-effector 112. In the described
implementation, adapter 155 includes two operative portions--a tool
receiver 157 adapted to connect the selected one or more surgical
tools 129, and the second operative part being one or more tongues
151 which may, in this implementation, be mounted and connected to
the distal end of adapter 155.
[0092] Adapter 155 has an outer perimeter 159 which, in this
implementation, is sized to oppose an inner perimeter 161 of
rotatable flange 147. Adapter 155 extends between proximal and
distal ends 163, 165, respectively and has an adapter bore 167
extending between ends 163, 165. Adapter bore 167 is sized to
receive at least one of the plurality of surgical tools 129, and
similarly, the distance between proximal and distal ends 163, 165
is selected so that at least one of tools 129 is secured to
end-effector 112 at the predetermined, appropriate height for the
surgical procedure associated with such tool received in adapter
bore 167.
[0093] In one possible implementation, system 100 includes multiple
ones of adapter 155, configured to be interchangeable inserts 169
having substantially the same, predetermined outer perimeters 159
to be received within inner perimeter 161 of rotatable flange 147.
Still further in such implementation, the interchangeable inserts
169 have bores of different, respective diameters, which bores may
be selected to receive corresponding ones of the tools 129 therein.
Bores 167 may comprise cylindrical bushings having inner diameters
common to multiple surgical tools 129. One possible set of
diameters for bores 167 may be 12, 15, and 17 millimeters, suitable
for multiple robotic surgery operations, such as those identified
in this disclosure.
[0094] In the illustrated implementation, inner perimeter 161 of
rotatable flange 147 and outer perimeter 159 of adapter 155 are
circular, having central, aligned axes and corresponding radii.
Slots 149 of rotatable flange 147 extend radially outwardly from
the central axis of rotatable flange 147 in the illustrated
implementation, whereas tongues 151 of adapter 155 extend radially
outwardly from adapter 155.
[0095] In still other implementations, end-effector 112 may be
equipped with at least one illumination element 171 (FIGS. 14 and
15) orientable toward the anatomical feature to be operated upon.
Illumination element 171 may be in the form of a ring of LEDs 177
(FIG. 14) located within adapter 167, which adapter is in the form
of a bushing secured to tool locking mechanism 117. Illumination
element 171 may also be a single LED 179 mounted on the distal
surface 123 of end-effector 112. Whether in the form of LED ring
177 or a single element LED 179 mounted on distal surface of
end-effector 112, or any other variation, the spacing and location
of illumination element or elements 171 may be selected so that
tools 129 received through bore 133 of end-effector 112 do not cast
shadows or otherwise interfere with illumination from element 171
of the anatomical feature being operated upon.
[0096] The operation and associated features of end-effector 112
are readily apparent from the foregoing description. Tool stop 121
is rotatable, selectively lockable, and movable between engaged and
disengaged positions, and a sensor prevents movement of
end-effector 112 when in such disengaged position, due to the
potential presence of a tool which may not be advisably moved
during such disengaged position. Tool-insert locking mechanism 117
is likewise rotatable between open and closed positions to receive
one of a plurality of interchangeable inserts 169 and tongues 151
of such inserts, wherein selected tools 129 may be received in such
inserts 169; alternately, tongues 151 may be otherwise associated
with tools 129, such as by having tongues 151 directly connected to
such tools 129, which tongue-equipped tools likewise may be
received in corresponding slots 149 of tool-insert locking
mechanism 117. Tool-insert locking mechanism 117 may be rotated
from its open position in which tongues 151 have been received in
slots 149, to secure associated adapters 155 and/or tools 129 so
that they are at appropriate, respective heights, angles of
orientation, and rotational positions relative to the anatomical
feature of the patient.
[0097] For those implementations with multiple adapters 155, the
dimensions of such adapters 155, including bore diameters, height,
and other suitable dimensions, are selected so that a single or a
minimized number of end-effectors 112 can be used for a
multiplicity of surgical tools 129. Adapters 155, such as those in
the form of interchangeable inserts 169 or cylindrical bushings,
may facilitate connecting an expanded set of surgical tools 129 to
the end-effector 112, and thus likewise facilitate a corresponding
expanded set of associated surgical features using the same
end-effector 112.
[0098] Another possible embodiment of surgical robot system 100
shown in FIG. 1A is described below and shown with reference to
FIGS. 21-25. In this implementation, end-effector 212 is suitably
connected to a robot arm, such as that described previously with
reference to robot arm 104, and is orientable to oppose an
anatomical feature a so as to be in operative proximity thereto.
End-effector 212 may include features similar to those described
with reference to end-effector 112 of FIGS. 12-18, such as a
tool-insert locking mechanism 217 and tool stop 221, which
correspond to tool-insert locking mechanism 117 and tools stop 121
described previously. However, it will be appreciated that such
features are not required in end-effector 212 and various other
features or configurations of end-effector 212 are contemplated by
the disclosure with reference to FIGS. 19-24.
[0099] End-effector 212 has a surgical tool comprising a drill 223
selectively connectible thereto. Processing circuitry, memory, and
suitable machine-readable instructions are associated with this
implementation of surgical robot system 100 so as to determine, for
drill 223, a drill target and an associated drill trajectory
relative to anatomical feature a. Suitable instructions are
likewise provided such that, when executed, the end-effector may be
automatically moved to a position corresponding to the determined
target and determined drill trajectory. Such instructions also
permit advancement of the drill toward the target. Manual
manipulations of end effector 212 to drill locations and
trajectories are likewise contemplated.
[0100] A drill guide 225 is releasably connected between drill 223
and end-effector 212. As explained below, drill guide 225 may be
configured and otherwise includes features to stop advancement of
drill 223 at a preselected drill depth associated with the
determined target. Drill guide 225 may be further configured with
features to guide the drill along the determined drill trajectory
during the advancement of the drill.
[0101] Drill guide 225 includes a guide shaft 227 having a bore 229
extending longitudinally therethrough between proximal and distal
ends of guide shaft 227. Bore 229 is sized to slideably receive a
drill bit 231 which extends distally from a chuck 233 of drill 223.
Such drill bit 231 terminates in a drill tip 235 capable of
engaging the anatomical feature a upon a suitable amount of
advancement of drill bit 231 along the determined drill
trajectory.
[0102] Referring more particularly to FIG. 22, drill bit 231 has a
known, that is, predetermined, length A corresponding to the
distance between the distal surface 237 of chuck 233 and the end of
drill tip 235. Guide shaft 227, in turn, has a known, that is,
predetermined, second length B. Drill guide 225 includes a depth
stop 239 having respective proximal and distal depth stop ends.
Depth stop 239 is mounted so that its distal depth stop end is
selectively and slideably received at the proximal end of guide
shaft 227. As such, depth stop 239, when slid relative to guide
shaft 227, varies the second length B of guide shaft 227. In
particular, movement of depth stop 239 varies the predetermined
length B of guide shaft 227 among a plurality or set of length
values corresponding to amounts by which drill tip 235 extends
beyond distal end of guide shaft 227, such amounts thus
corresponding to available drill depths. As such selected lengths B
are less than the known, predetermined length A of drill bit 231,
and thereby permit the distal end of drill bit 231 and its drill
tip 235 to extend distally from the distal end of guide shaft 227
by selected lengths corresponding to desired depths of engagement
of the anatomical feature. In the disclosed implementation, depth
stop 239 has surface 241 oriented and located to engage a distal
surface 237 of chuck 233 of drill 223. Accordingly, the depth to
which drill tip 235 is advanceable by drill 223 is limited by an
amount corresponding to the position of depth stop 239.
[0103] In one possible implementation, drill guide 225 includes a
visually perceptible depth indicator 251 operatively associated
with depth stop 239. By way of example, depth stop 239 has a
longitudinal stem 245 having indicia 243 disposed thereon, so that
slideable movement of depth stop 239 slides longitudinal stem 245
and the indicia 243. Guide shaft 227, in turn, has portions forming
a window 247 sized and located to reveal at least a portion of
longitudinal stem 245 bearing indicia 243. The portions adjacent to
window 247 have one or more structures or indicia thereon to form a
pointer 249. Indicia 243, in this case, includes a graduated,
numerical value scale associated with available depths of
penetration of anatomical feature a, the pointer and numerical
value scale being moveable relative to each other, in this case by
sliding longitudinal stem 245 of depth stop 239 relative to window
247 of guide shaft 227.
[0104] It will be appreciated that the above-described relative
arrangement of pointer 249 and graduated depths of advancement
appearing as numerical values in indicia 243 may be disposed in
alternative configurations, such as having the pointer on the
slideable longitudinal stem 245 and the graduated depths of
advancement disposed longitudinally along portions of window 247.
Still further variations are possible.
[0105] In still further possible implementation, drill guide 225
makes use of an engagement mechanism 253 which sets depth stop 239
at one of the available, selectable, longitudinal positions
corresponding to the desired or predetermined drill depth.
Engagement mechanism 253 may include a ratchet assembly 255 which
has features, such as mating teeth 257 as shown, to engage and set
depth stop 239 at one of the longitudinally spaced locations
between the proximal and distal ends of depth stop 239. In the
ratchet assembly 255 shown, teeth 257 are longitudinally disposed
along a suitable outer surface of longitudinal stem 245, and a
ratchet 259 with a confronting surface feature, such as one or more
mating teeth 257, is located to oppose teeth 257 disposed on stem
245 and is spring-biased to selectively engage stem 245.
[0106] Ratchet 259 and corresponding ratchet assembly 255 may be
operated by a spring-biased trigger 261. In the illustrated
embodiment, trigger 261 is manually pulled against a spring-biasing
force to disengage engagement mechanism 253 from a first one of the
longitudinal positions to which it had been previously set. During
such disengagement, depth stop 239 is operated to slide
longitudinal stem 245 relative to guide shaft 227 to a selected or
desired drill depth as indicated by pointer 249 relative to the
scale of indicia 243. After movement of depth stop 239 to the
desired longitudinal position, spring-biased trigger 261 may be
released, allowing the spring-biased force to set engagement
mechanism 253 at a second one of the available longitudinal
positions, the second longitudinal position corresponding to the
desired drill depth.
[0107] Once a desired drill depth has been set by the ratchet
assembly or other features of engagement mechanism 253, such
setting may be locked or secured against inadvertent movement by a
trigger lock 263 which is operatively connected to trigger 261,
meaning, when engaged, trigger lock 263 holds ratchet 259 engaged
with corresponding teeth 257 of depth stop. In the illustrated
implementation, trigger lock 263 may be in the form of a locking
ring 265, which may be threadibly or otherwise engaged to act as a
stop against disengagement of mating teeth 257 of ratchet 259, or
more generally, to prevent radially outward movement of ratchet 259
relative to the longitudinal axis of depth stop 239.
[0108] Actuation of engagement mechanism 253, including, for
example, engagement and disengagement of depth stop 239, may be
facilitated by providing drill guide 225 with a handle 267. Handle
267 may be pulled radially outwardly from the longitudinal axis of
drill guide 225 and, by virtue of connection to engagement
mechanism 253, such outward pulling of handle 267 overcomes
longitudinally inward spring-biasing force and disengages
engagement mechanism 253 from depth stop 239. Conversely, release
of handle 267 after desired sliding of depth stop 239 relative to
guide shaft 227 operates to set drill guide 225 at a desired drill
depth.
[0109] In addition to limiting penetration of drill 223 to a
desired drill depth, drill guide 225 may include features to reduce
deviation of drill bit 231 from the determined drill trajectory
.beta. (FIG. 21). In one suitable implementation, such trajectory
guiding features comprise at least one bushing 269 disposed within
bore 229. Bushing or bushings 269 are sized to receive outer
longitudinal surface 273 of drill bit 231 slideably and rotatably
therethrough. Accordingly, bushing 269 has an internal diameter
sized to not only moveably engage longitudinal surface 273, but to
thereby exert a force shown having the direction of arrow F
opposing lateral displacement of drill bit 231 within guide shaft
227 (FIG. 22). In one possible implementation, one bushing 269 is
located within guide shaft 227 toward distal end thereof and
thereby engages drill bit 231 closer to where drill tip 235 engages
anatomical feature a. Such distal locations of drill bit 231 often
experience greater lateral displacement forces by virtue of their
proximity to anatomical feature a to be engaged, especially in the
event the drill trajectory is at an oblique angle.
[0110] In the illustrated embodiment, a second bushing 269 is
disposed at a proximal location along guide shaft 227 and thereby
may generate a countervailing force opposing lateral displacement
at the proximal end of drill bit 231, such as would result from a
cantilevering of drill bit 231 upon oblique engagement of
anatomical feature a.
[0111] From the foregoing description, operations and related
methods of robot surgical system 100 and its drill guide 225 will
be readily appreciated. For example, in one method of operation,
drill 223 may be guided during robot-assisted surgery, including
any of the surgeries described herein on anatomical feature a of a
patient. A drill target and an associated drill trajectory are
determined, such as by computer processing. End-effector 212 is
manually or automatically moved to a position corresponding to the
determined target and the determined drill trajectory. After or
before such movement of end-effector 212, depth stop 239 may be
mechanically or manually set to one of a plurality of selectable
positions corresponding to the desired depth of advancement of the
drill associated with the contemplated surgery on the anatomical
feature. In this way, drill 223 is limited from penetrating the
anatomical feature beyond the selected, desired depth.
[0112] In one possible method, the displacement of the depth stop
is done with the aid of visually perceptible indicia corresponding
to graduated depths of advancement of the drill and, upon such
visual perception of the desired depth, the depth stop is secured
at such desired position. To set the depth stop, a spring-biased
trigger 261 is disengaged relative to depth stop 239 from a first
position, depth stop 239 is then longitudinally slid relative to
visually perceptible indicia 243 to a second position, such second
position corresponding to the desired position of the depth stop
and the desired depth of drilling on anatomical feature a. Once the
desired depth has been selected by movement of depth stop 239,
trigger 261 is released to re-engage depth stop 239 at the desired
position. Thereafter, trigger lock 263 may be further engaged to
avoid inadvertent disengagement and potential movement of depth
stop 239 and thereby avoid over drilling.
[0113] In the above-description of various embodiments of present
inventive concepts, it is to be understood that the terminology
used herein is for the purpose of describing particular embodiments
only and is not intended to be limiting of present inventive
concepts. Unless otherwise defined, all terms (including technical
and scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which present
inventive concepts belong. It will be further understood that
terms, such as those defined in commonly used dictionaries, should
be interpreted as having a meaning that is consistent with their
meaning in the context of this specification and the relevant art
and will not be interpreted in an idealized or overly formal sense
unless expressly so defined herein.
[0114] When an element is referred to as being "connected",
"coupled", "responsive", or variants thereof to another element, it
can be directly connected, coupled, or responsive to the other
element or intervening elements may be present. In contrast, when
an element is referred to as being "directly connected", "directly
coupled", "directly responsive", or variants thereof to another
element, there are no intervening elements present. Like numbers
refer to like elements throughout. Furthermore, "coupled",
"connected", "responsive", or variants thereof as used herein may
include wirelessly coupled, connected, or responsive. As used
herein, the singular forms "a", "an" and "the" are intended to
include the plural forms as well, unless the context clearly
indicates otherwise. Well-known functions or constructions may not
be described in detail for brevity and/or clarity. The term
"and/or" includes any and all combinations of one or more of the
associated listed items.
[0115] It will be understood that although the terms first, second,
third, etc. may be used herein to describe various
elements/operations, these elements/operations should not be
limited by these terms. These terms are only used to distinguish
one element/operation from another element/operation. Thus a first
element/operation in some embodiments could be termed a second
element/operation in other embodiments without departing from the
teachings of present inventive concepts. The same reference
numerals or the same reference designators denote the same or
similar elements throughout the specification.
[0116] As used herein, the terms "comprise", "comprising",
"comprises", "include", "including", "includes", "have", "has",
"having", or variants thereof are open-ended, and include one or
more stated features, integers, elements, steps, components or
functions but does not preclude the presence or addition of one or
more other features, integers, elements, steps, components,
functions or groups thereof. Furthermore, as used herein, the
common abbreviation "e.g.", which derives from the Latin phrase
"exempli gratia," may be used to introduce or specify a general
example or examples of a previously mentioned item, and is not
intended to be limiting of such item. The common abbreviation
"i.e.", which derives from the Latin phrase "id est," may be used
to specify a particular item from a more general recitation.
[0117] Example embodiments are described herein with reference to
block diagrams and/or flowchart illustrations of
computer-implemented methods, apparatus (systems and/or devices)
and/or computer program products. It is understood that a block of
the block diagrams and/or flowchart illustrations, and combinations
of blocks in the block diagrams and/or flowchart illustrations, can
be implemented by computer program instructions that are performed
by one or more computer circuits. These computer program
instructions may be provided to a processor circuit of a general
purpose computer circuit, special purpose computer circuit, and/or
other programmable data processing circuit to produce a machine,
such that the instructions, which execute via the processor of the
computer and/or other programmable data processing apparatus,
transform and control transistors, values stored in memory
locations, and other hardware components within such circuitry to
implement the functions/acts specified in the block diagrams and/or
flowchart block or blocks, and thereby create means (functionality)
and/or structure for implementing the functions/acts specified in
the block diagrams and/or flowchart block(s).
[0118] These computer program instructions may also be stored in a
tangible computer-readable medium that can direct a computer or
other programmable data processing apparatus to function in a
particular manner, such that the instructions stored in the
computer-readable medium produce an article of manufacture
including instructions which implement the functions/acts specified
in the block diagrams and/or flowchart block or blocks.
Accordingly, embodiments of present inventive concepts may be
embodied in hardware and/or in software (including firmware,
resident software, micro-code, etc.) that runs on a processor such
as a digital signal processor, which may collectively be referred
to as "circuitry," "a module" or variants thereof.
[0119] It should also be noted that in some alternate
implementations, the functions/acts noted in the blocks may occur
out of the order noted in the flowcharts. For example, two blocks
shown in succession may in fact be executed substantially
concurrently or the blocks may sometimes be executed in the reverse
order, depending upon the functionality/acts involved. Moreover,
the functionality of a given block of the flowcharts and/or block
diagrams may be separated into multiple blocks and/or the
functionality of two or more blocks of the flowcharts and/or block
diagrams may be at least partially integrated. Finally, other
blocks may be added/inserted between the blocks that are
illustrated, and/or blocks/operations may be omitted without
departing from the scope of inventive concepts. Moreover, although
some of the diagrams include arrows on communication paths to show
a primary direction of communication, it is to be understood that
communication may occur in the opposite direction to the depicted
arrows.
[0120] Although several embodiments of inventive concepts have been
disclosed in the foregoing specification, it is understood that
many modifications and other embodiments of inventive concepts will
come to mind to which inventive concepts pertain, having the
benefit of teachings presented in the foregoing description and
associated drawings. It is thus understood that inventive concepts
are not limited to the specific embodiments disclosed hereinabove,
and that many modifications and other embodiments are intended to
be included within the scope of the appended claims. It is further
envisioned that features from one embodiment may be combined or
used with the features from a different embodiment(s) described
herein. Moreover, although specific terms are employed herein, as
well as in the claims which follow, they are used only in a generic
and descriptive sense, and not for the purposes of limiting the
described inventive concepts, nor the claims which follow. The
entire disclosure of each patent and patent publication cited
herein is incorporated by reference herein in its entirety, as if
each such patent or publication were individually incorporated by
reference herein. Various features and/or potential advantages of
inventive concepts are set forth in the following claims.
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