Note: Descriptions are shown in the official language in which they were submitted.
SURGICAL ACCESS SYSTEM
TECHNICAL FIELD
[0001] The present disclosure relates generally to a surgical access system
for use with
delicate and critical tissues, as well as methods of accessing and performing
surgery using
same. The present disclosure also relates to treatment of a surgical sit.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] This application is a divisional of Canadian Patent Application No.
2,844,755,
filed October 24, 2012, which claims priority to U.S. Application No.
13/280,015 filed
October 24, 2011, U.S. Application No. 13/444,713 filed April 11,2012, U.S.
Application
No. 13/444,722 filed April 11,2012, U.S. Application No. 13/444,732 filed
April 11,2012,
and U.S. Application No. 13/474,433 filed May 17, 2012.
BACKGROUND
[0003] Diagnosis and treatment of conditions affecting the brain are among
the most
difficult and complex problems that face the medical profession. The brain is
a complex and
delicate soft multi-component tissue structure that controls bodily functions
through a
complex neural network connected to the rest of the body through the spinal
cord. The brain
and spinal cord are contained within and protected by significant bony
structures, e.g., the
skull and the spine. Given the difficulty of accessing the brain through the
hard bony
protective skull and the delicate network and complex interactions that form
the neural
communication network contained within the brain that define the human body's
ability to
carry on its functions of speech, sight, hearing, functional mobility,
reasoning, emotions,
respiration and other metabolic functions, the diagnosis and treatment of
brain disorders
presents unique challenges not encountered elsewhere in the body.
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[0004] For example, abnormalities such as intracranial cerebral hematomas
(ICH), abscesses,
glioblastomas (GB), metastases (mets) and functional diseases manifest
themselves in the
intraparenchymal subcortical space (i.e., the white matter) of the brain are
particularly
challenging to access, let alone treat. The ventricles of the brain contain
eloquent
communication structures (neural network) which are located in the subcortical
space, called
fiber tracts and fascicles. Thus, traditionally, unless the ICH, GB, and/or
mets were
considered anything but "superficial," such conditions have been considered
challenging to
access, simply because getting to the abnormality ICH, GB and/or mets are
considered just as
damaging as letting the condition take its course. Similarly, tissue
abnormalities such as
tumors, cysts and fibrous membrane growths which manifest within the
intraventricular space
of the brain are considered challenging to safely access and often inoperable,
due to their
locations within the brain.
10005] In order to assist in diagnosis and subsequent treatment of brain
disorders, clear,
accurate imaging of brain tissue through the skull is required. In recent
years significant
advances have been made in imaging technology, including stereotactic X-ray
imaging,
Computerized Axial Tomography (CAT), Computerized Tomographic Angiography
(CTA),
Position Emission Tomography (PET) and Magnetic Resonance Imaging (MRI),
Diffusion
Tensor Imaging (DTI) and Navigation systems (instrument position tracking
systems). These
imaging devices and techniques permit the surgeon to observe conditions within
the brain in a
non-invasive manner without opening the skull, as well as provide a map of
critical structures
surrounding an area of interest, including structures such as blood vessels,
membranes, tumor
margins, cranial nerves, including fiber tracts and fascicles. If an
abnormality is identified
through the use of one or more imaging modalities and/or techniques, it may be
necessary or
desirable to biopsy or remove the abnormality.
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100061 Once a course of action has been determined based upon one or more
imaging
techniques, a surgical treatment may be necessary or desired. In order to
operate surgically
on the brain, access must be obtained through the skull and delicate brain
tissue containing
blood vessels and nerves that can be adversely affected by even slight
disturbances.
Therefore, great care must be taken in operating on the brain so as not to
disturb delicate
blood vessels and nerves to prevent adverse consequences resulting from a
surgical
intervention.
100071 Traditionally, accessing abnormalities which manifest in deeper
spaces within the
brain has meant a need for a surgery that creates a highly invasive approach.
In some
instances, in order to obtain access to target tissue, a substantial portion
of the skull is
removed and entire sections of the brain are retracted to obtain access. For
example, surgical
brain retractors are used to pull apart or spread delicate brain tissue, which
can leave pressure
marks from lateral edges of the retractor. In some instances, a complication
known as
"retraction injury" may occur due to use of brain retractors. Of course, such
techniques are
not appropriate for all situations, and not all patients are able to tolerate
and recover from
such invasive techniques.
100081 It is also known to access certain portions of the brain by creating
a burr hole
craniotomy, but only limited surgical techniques may be performed through such
smaller
openings. In addition, some techniques have been developed to enter through
the nasal
passages, opening an access hole through the occipital bone to remove tumors
located, for
example, in the area of the pituitary. These approaches are referred to as
Expanded
Endonasal Approaches (EEA) and were pioneered by one of the inventors of this
disclosure.
[0009] A significant advance in brain surgery is stereotactic surgery
involving a
stereotactic frame correlated to stereotactic X-ray images to guide a
navigational system
probe or other surgical instrument through an opening formed in the skull
through brain
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tissue to a target lesion or other body. A related advance is frameless image
guidance, in
which an image of the surgical instrument is superimposed on a pre-operative
image to
demonstrate the location of the instrument to the surgeon and trajectory of
further movement
of the probe or instrument. However, once the navigational system probe is
removed,
information concerning the location of any retractors or other surgical
instruments that may
be used during procedures is unavailable.
[0010] In recent years, surgical access systems have been developed to
provide access to
previously difficult to access areas. One such prior art system is shown in
FIGS. IA-IC.
System 10 includes a retractor 20 and an introducer 40. Introducer 40 includes
a cone-shaped
distal end 42 with an opening 52 therein (best seen in FIG. IC). The cone-
shaped distal end
is configured to be a generally blunt, flat surface. With introducer 40
positioned within
retractor 10, system 10 is inserted into brain tissue, thereby pushing brain
tissue away while
providing access to an area of interest. Once system 10 is delivered to the
area of interest,
retractor 10 is rigidly fixed in position. More specifically, retractor 10 is
fixed in space with
the use of a standard or conventional neurosurgical fixation device. Once,
retractor 10 is
fixed in place, introducer 40 is then removed from retractor 10, while leaving
retractor 10 in
its fixed place, thereby creating a pathway through the brain tissue. However,
no mechanism
for providing navigational information concerning the retractor 10 with
respect to the
patient's anatomy is provided.
[0011] While access system 10 may provide a manner to access certain brain
tissue, the
blunt shaped distal end of can actually cause transient or even permanent
deformation and
trauma of delicate tissue structures which can manifest itself in temporary or
permanent
neurological deficits after surgical cytoreduction due to damage of blood
vessels, cranial
nerves, fiber tracts and fascicles. Opening 52 may cause coring of tissue,
also leading to
damage of the tissues and structures as introducer 40 is pushed through
tissue. Further, by
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rigidly fixing the placement of retractor 10, manipulation of retractor 10 is
impeded and
requires constant attention by loosening and retightening to re-position for
even micro-
movement of the retractor 10, without critical information concerning
surrounding structures
in relation to the retractor 10 available, thereby lengthening procedure time.
[0012] Another issue that needs to be addressed is visibility. Typically
when employing
an access system in a surgical procedure, it is often like operating in a
poorly lit tunnel. To
provide illumination, it is known to place a light source within the
introducer sheath, such as
an endoscope. However, when using an endoscope, the light source takes up a
significant
amount of working space within the introducer sheath, thus reducing the
functional working
area for other instruments, as well as minimizing the ability to move other
instruments within
the surgical site.
[0013] Alternatively, light must be delivered from a remote or external
location, such as a
microscope or exoscope. However, in the case of microscopes and exoscopes, the
external
light source is often blocked by the surgeon and/or instruments in the
surgical field. At a
minimum, the effectiveness is greatly diminished at the distal end of the
introducer sheath
where the actual surgical work and/or treatment is occurring, and where
effective
visualization is needed the most.
[0014] Notwithstanding the foregoing advances in imaging technology and
both frame
and frameless stereotactic image guidance techniques, there remains a need for
improved
surgical techniques and apparatus for operating on brain tissue, including
improved
navigational capabilities.
[0015] There also exists a need for improved and effective treatment
regimens and
options. Traditionally, once diseased tissue is removed, patients are treated
with a "one-size"
fits all approach which typically includes a generic and heavy chemotherapy
protocol
regimen which is delivered systemically which affects the entire body and is
designed to
CA 3010024 2018-06-28
provide a balance between enough poison to kill the cancerous cells and tissue
without killing
the healthy tissues. High doses and multiple exposures to radiation are also
typically used
and delivered by products such as the Gamma Knife and Cyber Knife. However,
such
treatment regimens are often nothing more than a series of "experiments" on
the patient in an
effort to find an effective treatment plan. Accordingly the patient must be
monitored to
ascertain the effectiveness of the generic therapeutic regimen and continuous
modification
and tweaking of the treatment regime is performed based upon the positive or
negative results
of each of the previous successes or failures while attempting to balance the
sparing of
healthy tissues and poisoning effect of the treatment process on the whole
patient. Such a
treatment regime effectively results in the patient being a guinea pig until a
treatment regime
is achieved to manage the disease or as in most cases of brain cancers the
patient dies from
the disease. Unfortunately, in the case of brain cancers, the patient often
succumbs to the
disease before an effective treatment regime is achieved. Regardless of these
heroic clinical
efforts that are very biologically caustic to the patient, rarely are any of
the current treatment
paradigm curative. In fact, since patients diagnosed with brain cancers often
do not typically
live beyond 9 ¨ 14 months after initial diagnosis of the disease, long term
clinical
implications of whole body chemo or target directed radiation therapy are
unknown in these
patients and may be detrimental if the patient lived long enough for the true
impact to be
understood.
[0016] In addition, most current therapeutic treatment regimens involve
delivering
immunotherapy or chemotherapy regimens systemically and depend on delivery
through the
bloodstream. However, the blood-brain barrier, which serves to separate
circulating blood
from the brain extracellular fluid in the central nervous system (CNS),
creates additional
challenges to delivering therapeutic agents to specific regions of the brain
through the
bloodstream. More specifically, the blood-brain barrier actually functions in
a
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neuroprotective role. Thus the blood-brain barrier actually impedes delivery
of therapeutic
agents to the brain. Therapeutic molecules that might otherwise be effective
in therapy are
typically larger molecules than the blood brain barrier sieve and for this
reason do not cross
the blood brain barrier in adequate amounts. In addition to the blood brain
barrier other
mechanisms exist within the body to filter out foreign materials and chemicals
such as the
liver and the kidneys. These filtering create additional challenges for the
delivery of
appropriate concentrations of therapeutics the intended site of treatment for
central nervous
system diseases.
[0017] To overcome the treatment issues associated with the blood brain
barrier,
mechanical opening of the blood brain barrier has been proposed, which may
complicate the
procedure. In addition, use of smaller particles (i.e., nano-particles) have
been proposed,
whereby the smaller particles are sized to pass through the blood brain
barrier, then are
attempted to be recombined to form a larger and more effective therapeutic
molecule.
However, in some instances, the smaller particles fail to recombine in
therapeutic levels.
Other means to breach the blood brain barrier include delivering chemicals
designed to
temporarily open up the blood brain barrier to allow for a period of time that
larger molecules
at therapeutic levels may pass across it. Once across the blood brain barrier,
the therapeutic
treatment must still get to the diseased tissue, resulting in poisoning
healthy tissue, as well as
diseased tissue.
[0018] Additionally, it is believed that since certain diseases of the
brain, such as cancers
and other abnormalities, often behave like a virus or bacteria in that once
they are treated, but
not eradicated by the therapeutic regimen delivered to them, they may morph
and become
resistant to the treatment that had been previously delivered to them. These
residual
unaffected abnormal cells may mutate into a strain of cells that become
resistant to the
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therapy that was delivered to them previously. In cases of functional
diseases, the
effectiveness of treatment on brain tissue may be difficult to evaluate.
[0019] Accordingly, there exists a need for effective treatment regimes
that overcomes
the challenges created by the blood brain barrier, while providing targeted
treatment to the
diseased tissue rather than healthy and diseased tissue. There also exists a
need for a method
of evaluating effectiveness of treatment.
SUMMARY
[0020] According to one aspect of the disclosure, surgical access assembly
is disclosed
that comprises an outer sheath and an obturator. The outer sheath is defined
by an open distal
end and an open proximal end and includes a hollow body portion therebetween.
The
obturator is defined by a distal end and a proximal end, wherein the distal
end further
comprises a tapered distal tip member that terminates in a distal tip. The
obturator is
configured to be received within the outer sheath such that the tapered distal
tip member
protrudes from the open distal end of the outer sheath when the obturator is
in an introducing
configuration.
[0021] In one embodiment, the distal end of the outer sheath further
comprises a radiused
rim.
[0022] In one embodiment, a grip portion is secured to the open proximal
end of the outer
sheath. The outer surface of the grip portion may be textured. In one
embodiment, at least
one small opening formed through grip portion causes the texturing. In another
embodiment,
a plurality of small openings spaced equi-distantly about the grip portion
form the texturing.
[0023] In one exemplary arrangement, a locating member may extend from a
periphery
of the grip portion.
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[0024] In one exemplary arrangement, the body portion of the outer sheath
is transparent.
[0025] In one embodiment, the body portion further comprises at least one
reference
indicator that is configured to visually indicate a predetermined location on
outer sheath. A
plurality of indicators may be provided, the indicators spaced apart equi-
distance from one
another about the circumference of the body portion. In one embodiment, the
reference
indicator is a longitudinal indicator that extends from the proximal end to
the distal end. In
one embodiment, the reference indicator is printed onto one of the internal
and external
surface of the body portion with an imageable visible ink. In one embodiment,
the reference
indicator etched onto one of the internal and external surface of the body
portion. In one
embodiment, the plurality of the indicators are one of a series of spaced
apart small holes and
non-through divots.
[0026] The obturator may further comprise a body potion extending between
the distal
end and the proximal end, and further comprising a handle portion fixedly
connected to the
proximal end, wherein the handle portion further comprises a first stop member
and a grip
member. A locking member may be operatively connected to the handle portion
and an
engagement opening that is in communication with a receiving aperture that
receives the
locking member may be provded. The engagement opening is in communication with
a
channel that receives a retaining member that is configured to retain the
locking member to
the handle portion.
100271 In one exemplary embodiment, the body portion further comprises at
least one
void area.
[0028] In one embodiment, the body portion may further comprise at least
one
compensating protuberance on an outer surface of the body portion.
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[0029] The body portion may further comprise a channel segment disposed
therein, the
channel segment configured to receive a navigation member. In one arrangement,
the
channel segment terminates in depression that aligns with a proximal edge of
the tapered
distal tip member.
[0030] In one embodiment, the obturator further comprises at least one
viewing window
disposed in the tapered distal tip member, the viewing window in communication
with a
channel that is configured to receive a viewing member to permit visualization
of tissue.
[0031] In one embodiment, the surgical access assembly further comprises an
illuminating ring that operatively connects to a portion of the outer sheath,
wherein the
illuminating ring comprises a top surface, a wall member and at least one
light element
carried by the illuminating ring, wherein an access opening is formed through
the top surface
of the illuminating ring.
[0032] In one embodiment, the light element is a plurality of LED lights. A
plurality of
light elements may be provided, with the light elements being spaced equi-
distantly about the
access opening.
[0033] In one embodiment, the wall of the illuminating ring further
comprises a wall
opening that is configured to receive a locating element to selectively secure
the illuminating
ring to the outer sheath.
[0034] In one embodiment, a navigating member that operatively connects one
of the
obturator, outer sheath or light ring to a navigation system is provided. The
navigational
element is configured to indicate the location of the outer sheath or
obturator within a patient
during use. The navigation member may be one of an RFID chip, sensor,
ultrasound probe, a
plurality of reflective members, an array, or an imaging device positioned
within obturator.
CA 3010024 2018-06-28
[0035] In one embodiment, the navigational element is permanently attached
to a portion
of the outer sheath. In another embodiment, the navigational element is
impregnated or
molded into the body portion of the outer sheath.
[0036] In one embodiment, the illumination ring further comprises at least
one outwardly
extending flange member positioned on a periphery of a wall member of the
illumination
ring, and the navigational element includes at least one sensor that
operatively mounted to the
flange member. The at least one sensor is electrically connected to a circuit
board positioned
in the illumination ring.
[00371 In one embodiment, the illumination ring further comprises a
plurality of
outwardly extending flange members positioned on a periphery of a wall member
of the
illumination ring, and wherein the navigational element includes a plurality
of reflective balls
that serve as position indicators, wherein one of the reflective balls are
mounted to each
flange member.
[0038] In one embodiment, a support ring that is configured to be mounted
to the outer
sheath is provided. The navigational element is mounted to the support ring
such that when
the support ring is connected to the outer sheath, the navigation system is
configured to track
the location of the outer sheath so as to indicate the position of the outer
sheath with respect
to a patient's anatomy.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Exemplary embodiments of the present disclosure will now be
described in
greater detail with reference to the attached figures, in which:
[0040] FIGS. 1A-1C illustrate a prior art surgical access system.
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[0041] FIG. 2 is a perspective cross-sectional view of an exemplary
arrangement of a
surgical access assembly.
[0042] FIG. 3 is a perspective view of an outer sheath of the surgical
access assembly of
FIG. 2.
[0043] FIG. 4A is a side elevational view of the outer sheath of FIG. 3.
[0044] FIG. 4B is an enlarged cross-sectional view of a portion of the
distal end of the
outer sheath of FIG. 4A.
[0045] FIG. 4C is an enlarged cross-sectional view of a portion of an
alternative
embodiment of the distal end of the outer sheath of FIG. 4A.
[0046] FIG. 5 is an end view of outer sheath of FIG. 3.
[0047] FIG. 6A is an elevational view of an alternative embodiment of an
outer sheath.
[0048] FIG. 6B is an end view of the outer sheath of FIG. 6A.
[0049] FIG. 7A is a perspective view of an obturator assembly of the
surgical access
assembly of FIG. 2.
[0050] FIG. 7B is an enlarged view of an end face of the obturator assembly
taken from
area 7B of FIG. 7A.
[0051] FIG. 8A is a top view of the obturator assembly of FIG. 7A.
[0052] FIG. 8B is an enlarged view of a distal end of the obturator
assembly taken from
area 8B of FIG. 8A.
[0053] FIG. 8C is an alternative embodiment of the distal end of the
obturator assembly
taken from area 8B of FIG. 8A.
[0054] FIG. 8D is an alternative embodiment of the distal end of the
obturator assembly
taken from area 8B of FIG. 8A.
[0055] FIG. 9A is a side elevational view of the obturator assembly of FIG.
7A.
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[0056] FIG. 9B is an enlarged view of a potion of the obturator assembly
taken from area
9B of FIG. 9A.
[0057] FIG. 10 is an end view of the obturator assembly of FIG. 7A.
[0058] FIG. 11A is a perspective view of an illuminating ring that
operatively connects to
an outer sheath of the surgical access assembly.
[0059] FIG. 11B is a side view of the illuminating ring of FIG. 11A.
[0060] FIG. 11C is atop view of the illuminating ring of FIG. 11A.
[0061] FIG. 11D is a bottom plan view of the illuminating ring of FIG. 11A.
[0062] FIG. I I E is a cross-sectional view of an exemplary arrangement of
a lighting
arrangement for the illuminating of FIG. 11 A.
00631 FIG. 11F is a plan view of a circuit board for use with the
illuminating ring of
11A.
[0064] FIG. 11G is an exemplary electrical schematic for use with the
illuminating ring
of FIG. 11A.
[0065] FIG. 11H is a top plan view of an alternative arrangement of the
illuminating ring
of FIG. 11A.
[0066] FIG. 111 is a bottom plan view of the illuminating ring of FIG. 11H.
[0067] FIG. 12 illustrates the illuminating ring of FIG. 11A assembled to
an exemplary
embodiment of the outer sheath.
[0068] FIG. 13 is a flow chart illustrating a process flow using the
surgical access
assembly.
[0069] FIG. 14A-14B are images of a brain illustrating an area of interest,
taken using an
imaging modality.
[0070] FIG. 15 is an image taken of the brain shown in FIGS. 14A-14B,
illustrating
various critical structures, such as fiber tracts and fascicles of the brain.
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[0071] FIG. 16A is an alternative embodiment of an obturator with an
imaging device
operatively connected thereto.
[0072] FIG. 16B is a partially exploded view of an enlarged cross-sectional
view of the
proximal end of the obturator and post.
[0073] FIG. 16C is an alternative arrangement of a coil sensor for use with
an obturator.
[0074] FIG. 16D is an end view of the coil sensor mounted on the post of
FIG. 16C.
[0075] FIG. 17A is an elevational view of the surgical access system, while
the obturator
is being withdrawn from the outer sheath.
[0076] FIG. 17B is an elevational view of the surgical access system with
the outer
sheath in place within the brain.
[0077] FIG. 18 is a perspective view of an exemplary surgical device used
for
cytoreduction.
[0078] FIG. 19A is an elevational view of an exemplary manipulation member.
[0079] FIG. I9B is an elevational view of an alternative manipulation
member.
[0080] FIG. 19C is top view of the outer sheath operatively connected to a
first
exemplary arrangement of a holding arrangement therefore.
[0081] FIG. 19D is an elevational view of the outer sheath and holding
arrangement of
FIG. 19C.
[0082] FIG. 19E is a top view of the outer sheath operatively connected to
a second
exemplary arrangement of a holding arrangement therefore.
[0083] FIG. 19F is an elevational view of the outer sheath and holding
arrangement of
FIG. 19C.
[0084] FIG. 19G is a side elevational view of the outer sheath operatively
connected to a
third exemplary arrangement of a holding arrangement therefore and an
exoscope.
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[0085] FIG. 19H is a perspective elevational view of the outer sheath,
holding
arrangement and exoscope of FIG. 19G.
[0086] FIG. 191 is an enlarged perspective view of a top portion of the
outer sheath,
illustrating the connection of the holding arrangement to the outer sheath.
[0087] FIG. 19J is a top view of the top portion of the outer sheath,
illustrating an
alternative connection of the holding arrangement of FIGS. 19G-H.
[0088] FIG. 20 is a partial perspective view of an exemplary delivery
sleeve that may be
used with a surgical device.
[0089] FIG. 21A is an exemplary arrangement for a therapy delivery
device.
[0090] FIG. 21B is an alternative arrangement of the therapy delivery
device of FIG.
21A.
[0091] FIG. 22 is a flow chart illustrating a process flow for follow-up
therapy whereby
the surgical access assembly may be employed.
DETAILED DESCRIPTION
[0092]
100931 Described herein is surgical access assembly, various
components for use in
same, and a method of using the surgical access assembly. The components
disclosed herein
provide surgeons with an enhanced ability to minimize trauma to the patient,
while providing
efficient improved minimally invasive surgical techniques, such as, for
example, during
CA 3010024 2019-11-08
intracranial surgical techniques. The components disclosed herein may further
be used for
application of targeted and effective treatment regimens.
[0094] Referring to FIG. 2, a perspective cross-sectional view of a
surgical access
assembly 100 is shown. In one exemplary arrangement, surgical access assembly
100
comprises a hollow outer sheath 102 and a selectively removable obturator 104.
As best seen
in FIG. 2, obturator 104 is configured with a length that is longer than a
length of outer sheath
102 such that a distal end 106 of obturator 104 protrudes a predetermined
distance from a
distal end 108 outer sheath 102, as will be discussed below in greater detail.
[0095] A locking member 110 may also be provided. Locking member 100 is
configured
to operatively retain a separate navigation member 112 (shown in phantom)
within obturator
104, as will be discussed in greater detail below. A retaining member 114 may
be secured
within a portion of obturator 104 to prevent locking member 110 from being
completely
disengaged from obturator 104.
[0096] Referring now to FIGS. 3-5, outer sheath 102 will be described in
greater detail.
Outer sheath 102 is defined by distal end 108 and a proximal end 116 and
includes a
generally hollow body portion 118 and a grip portion 120. In one exemplary
arrangement,
grip portion 120 is configured as a ring, as illustrated in the drawings.
However, it is
understood that grip portion 120 need not be configured as a ring. For ease of
explanation,
grip portion 120 will be referred to hereinafter as grip ring 120. Grip ring
120 is fixedly
secured to body portion 118 at proximal end 116. In one exemplary arrangement,
body
portion 118 is constructed of a clear biocompatible material that permits
viewing of normal
tissue, abnormal tissue, as well as critical structures that are disposed
outside of body portion
118 when outer sheath 102 is disposed within such tissue. In one exemplary
arrangement,
outer sheath 102 is constructed of polycarbonate, though other biocompatible
materials may
be employed, including resins.
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100971 In one exemplary configuration, an imaging mechanism may be
incorporated into
outer sheath 102 that would permit visualization of tumors, vessels, fiber
tracks, fascicles and
even healthy tissue, in real-time. Indeed, as will be explained in further
detail below, the
imaging mechanism will enable physiological functional imaging to provide
information
about the characteristics of the cortical fiber tracks to be visible, thereby
enabling a user to
separate and park such fibers on either side of outer sheath 102 rather than
cutting, stretching
and potentially damaging such fibers while gaining access to a desired
location within the
brain. Further, as will be explained in further detail below, the imaging
mechanism may also
enable the surgeon to have real-time information about the fiber tract and
fascicle location,
after placement of outer sheath 104, and during abnormality resection
procedure
therethrough. In addition to white matter tract imaging, mapping of the
characteristics of the
cerebral blood flow may be obtained.
100981 In one exemplary embodiment, the imaging mechanism may be an
ultrasound
probe incorporated into outer sheath 102. For example, outer sheath 102 may be
provided
with one or more channels within the wall that defines outer sheath 102 that
are configured
with one or more small diameter ultrasound probes. In another arrangement, a
single
ultrasound probe that is configured to be received within outer sheath 102 may
be provided.
In yet another embodiment, a low field MRI probe may be selectively placed in
outer sheath
102 to provide enhanced imaging. In yet another embodiment a low field MRI
imaging coil
may be molded into or bonded into outer sheath 102. In still another exemplary
arrangement,
the probe may be an optical coherent tomography (OCT) imaging or spectroscopy.
[0099] In another exemplary arrangement, as will be explained in further
detail below,
outer sheath 102 may also be (or alternatively be) provided navigational
capabilities that
permit a user to "read" the location of outer shaft 102 after placement at an
area of interest, as
well as update the location of outer sheath 102 during a procedure. In one
exemplary
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arrangement, an RFID chip or sensor that is configured to be tracked by a
navigation system,
may be incorporated into outer sheath 102. For example, an RFID chip or sensor
may be
permanently attached to outer sheath 102, for example, by impregnating or
molding the RFID
chip or sensor therein. In other exemplary arrangements, a temporary sensor or
chip may be
incorporated into or attached to outer sheath 102. For example, outer sheath
102 may be
provided with one or more channels within the wall that defines outer sheath
102. An RFID
chip and/or sensor may be positioned within the channels. Alternatively, the
RFID chip
and/or sensor may be positioned within grip ring 120.
[00100] In yet another alternative arrangement, and RFID chip or sensor may be
mounted
to the grip ring 120. Further, in yet another arrangement, reflective balls
may be mounted on
a distal facing surface (best seen in FIG. 3) of grip ring 120 (similar to
what is described
below in connection with FIGS. 11H-1). Reflective balls act as image guidance
position
indicators, such as an array of reflectors of the type use in connection with
optical image
guidance systems. The infrared reflector balls used with such a system are
mounted in a
customary triangular configuration calibrated to identify the outer sheath to
the
image/navigational guidance system.
[00101] Distal
end 108 of outer sheath 102 may be configured with a tapered portion 130
that extends towards a center axis A-A of outer sheath 102 to a distal edge
132 that surrounds
an opening 134 in distal end 108 of outer sheath 102. Tapered portion 130
serves to ease the
transition between outer sheath 102 and a distal tip potion 172, without drag,
trauma or
coring of tissue from a diameter that defines a body portion 168 of obturator
104 to a
diameter that defines body portion 118 of outer sheath 102. In one exemplary
configuration,
distal end 108 may be configured with a radius or other configuration so as to
create a
smooth/atraumatic transition of the brain tissue when surgical access assembly
100 is inserted
into the brain.
18
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õ
[00102] For
example, as best seen in FIG. 4B, distal edge 132 is configured so as to be
non-sharpened and radiused. In one exemplary arrangement, distal edge 132 is
configured as
a 0.3 mm diameter radiused rim. Tapered portion 130 and radiused distal tip
132 cooperates
with obturator 104 to atraumatically move tissue, as well as various
structures within the
brain, including white matter, away from outer sheath 102 without cutting
tissue or such
structures. Indeed, unlike prior art devices that include either a blunt tip
distal end or a
tapered leading edge such as that shown in FIG. 1C, radiused distal tip 132
cooperates with
tapered portion 130 and obturator 104 to prevent bruising and damage to
various tissue.
More specifically, this configuration facilitates entry of outer sheath 102
into delicate tissue,
but without cutting such delicate tissue. Insertion of surgical access
assembly 100 will be
explained in further detail below.
[00103] Body portion 118 may further be provided with a plurality of spaced
apart
indicators 136. Indicators 136 generally extend about the circumference of
body portion 118
and each may further incorporate a secondary indicator 138 that visually
illustrates a
predetermined location on body portion 118, as shown in FIG. 3. While FIG. 3
illustrates
four indicators 136, it is understood that body portion 118 may be provided in
a variety of
lengths and that any number of indicators 136 may be provided. Body portion
118 may also
be provided with a longitudinal indicator 140. More specifically, as best seen
in FIG. 4A,
longitudinal indicator 140 extends from proximal end 116 to distal end 108.
Indicators 136,
138 and 140 may be printed onto either an internal or external surface of body
portion 118
with an imaging visible ink such as, for example ink containing fluro-
deoxyglucose (FDG),
Technicium 99, Gadolinium, titanium dust, barium sulfate, a combination of the
above or
other suitable imaging material. Indicators 136 and 138 provide a reference
point for the
operator of system 100, as structures may be visible through body portion 118.
Indicator 136,
138 and 140 may also be configured to be visible under MRI, CT, PET, or any
other suitable
19
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imaging modality to enable easy identification of areas of interest. In one
alternative
embodiment, indicators 136, 138 and/or 140 may be etched or printed onto body
portion 118,
either on the internal or external surface of body portion 118.
100104] Details of grip ring 120 are best seen in FIG. 5. Grip ring 120 is
generally
configured as a flange member 142 defined by an outer periphery 144 and an
inner opening
146. Inner opening 146 may be sized to generally correspond to the diameter of
a lumen 148
defined by body portion 118. Outer periphery 144 is sized to have a diameter
that is larger
than lumen 148 of body portion 26. Flange member 142 may further be provided
with one or
more small openings 150 that are disposed therein. In one exemplary
arrangement, a
plurality of small openings 150 are provided that are spaced generally equi-
distantly about
inner opening 146. Small openings 150 will be described in further detail
below. Outer
periphery 144 may further be provided with a textured surface 152 to provide
for ease of
gripping outer sheath 102. For example, in one exemplary arrangement, textured
surface 152
comprises a plurality of alternating ridges 154 and grooves 156. However, it
is understood
that other textured surfaces may be employed.
1001051 Disposed on a proximal end surface 158 of flange member 142, an
alignment
feature 160 may be employed. Alignment feature 160 is used to indicate the
location of
longitudinal indicator 140 when outer sheath 102 is positioned within the
brain. Alignment
feature 160 will be discussed below in greater detail.
1001061 An alternative embodiment of outer sheath 202 is shown in FIGS. 6A-6B.
Outer
sheath 202 is similar to outer sheath 102 in that it is defined by a distal
end 208, a proximal
end 216 and a body portion 218. A distal edge 232 is generally configured to
be similar as
distal tip 132. A grip ring 220 is fixedly secured to body portion 218.
1001071 Grip ring 220 also includes a textured surface 252. Grip ring 220
further includes
a locating member 262. Locating member 262 is configured to operatively
connect an
CA 3010024 2018-06-28
illumination ring (best seen in FIG. 11A) 300 to outer sheath 102. As may be
seen, in one
exemplary configuration, locating member 262 extends outwardly from outer
periphery 244
of grip ring 220. Locating member 262 may also serve as an alignment feature
for indicating
the location of longitudinal indicator 240. Alternatively, a separate
alignment feature 260
may be provided. For example, in FIG. 6B, alignment feature 260 is positioned
adjacent
locating member 262.
1001081 Body portion 218 may also be provided with indicators 34, 36, and 38
to assist in
locating outer sheath 202 in operation. However, in another alternative
arrangement, body
portion 218 may be provided with indicators 264 that produce a signal void or
minimal
artifact under certain imaging modalities. In one specific arrangement,
indicators 264 may be
configured as small holes that are spaced apart at predetermined distances, as
shown in FIG.
6A. In yet another alternative arrangement, indicators 264 may be configured
as non-through
divots. In still a further alternative arrangement, indicators 264 may be
configured as a
longitudinal groove (not shown) on either the internal or external surface of
body portion
218.
1001091 Referring to FIGS. 7-10, obturator 104 will now be described.
Obturator 104 is
defined by distal end 106, a proximal end 166, a body portion 168 and a handle
portion 170.
Distal end 106 is configured with a generally conical shaped distal tip
portion 172 that tapers
to a tip member 174 to provide atraumatic dilation of tissue. In one exemplary
arrangement,
tip portion 172 tapers toward a closed tip member 174 so as to prevent coring
of tissue as
obturator 104 is inserted into the brain.
[00110] There are a number of variables that play the selection of the angle a
that defines
the taper of tip portion 172. These variables include the size of an outer
diameter D1 of
obturator 104, the desired length that distal tip portion 172 extends from
body portion 168,
and the desired offset for a distal tip of navigation member 112 and tip
member 174. More
21
CA 3010024 2018-06-28
specifically, it is contemplated that surgical access assembly 100 will be
provided as part of a
kit that may include multiple sized outer sheaths 102 and obturators 104, to
provide the
surgeon with a choice of different diameter sizes and lengths so as to provide
flexibility for
accessing areas of interest within the brain. However, to insure that the
distal tip 174 is
determinable regardless of which size diameter DI of obturator 104 is used,
taper angle a
may be selectively adjusted. For embodiments that utilize navigation member
112 that
positions a distal end thereof at a set position within obturator 104 (as will
be explained in
further detail below), to maintain an identical offset length between the
distal end of
navigation member 112 and distal tip 174 in different diameter D1 sized
obturators 104, taper
angle a will need to be increased, as diameter DI increases.
100111] For example, if diameter DI of obturator 104 is 13.5mm, an exemplary
angle a
may be 45.5 to provide effective atraumatic dilation, as well as a
determinable distal tip 174
location. However, if diameter DI of obturator 104 is 15.5mm, an exemplary
angle a' may
be 52.8 .
[00112] As best
seen in FIG. 8B, distal tip 174 is configured to be radiused such that tip
member 174 is rounded, and neither blunt, nor sharp. More specifically, tip
member 174 is
configured so as not to have any flat portions which during insertion can
stretch or even tear
the delicate tissues such as the vessels, fiber tracts and fascicles found in
the brain. Further,
because tip member 174 is closed, damage of such delicate tissues and
fascicles are also
avoided. In one exemplary embodiment, tip member 174 is configured with a 0.5
mm radius.
As will be explained in further detail below, the configuration of tip member
174 is designed
to gently displace and move the tissue into which it is inserted; i.e.,
atraumatically dilate the
tissue to allow for introduction in to an intra-fascilar and para-fascilar
manner, as opposed to
cutting tissue as surgical access assembly 100 is inserted into the tissue.
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[00113] Handle portion 170 is positioned at proximal end 166 of obturator
104. As best
seen in FIGS. 7B, 8A and 9A, handle portion 170 comprises a stop member 176
and a grip
member 178. Stop member 176 is positioned distally of grip member 178 and, as
best seen in
FIG. 8A, is configured to have a width W1 that is greater than a diameter D1
of body portion
168, as well as a diameter D2 of outer sheath 102 (shown in FIG. 4A). Grip
member 178 is
configured with a width W2 that is greater than the width W1 of stop member
176, thereby
providing a step-like configuration. Stop member 176 further defines an
engagement surface
177 that is axially spaced from a distal surface 179 of grip member 178.
[00114] In one exemplary arrangement, handle portion 170 is configured with a
generally
planar surface 180, as best seen in FIGs. 7A-7B and FIG. 10. Planar surface
180 is
configured with a receiving aperture 182 that is configured to receive locking
member 110.
In one exemplary arrangement, receiving aperture 182 is threaded. As best seen
in FIGS. 2,
7B, and 8A, disposed within receiving aperture 182 is an engagement opening
184.
Engagement opening 184 is in communication with a channel 186 (seen in phantom
in FIGS.
8A and 9A) that extends at least partially thorough handle portion 170. After
locking
member 110 is at least partially engaged within receiving aperture 182,
retaining member 114
(FIG. 2) is positioned within channel 186. Because engagement opening 184
opens into
receiving aperture 182, a portion of retaining member 114 extends across a
portion of
receiving aperture 182 such that locking member 110 is prevented from being
entirely
withdrawn from receiving aperture 182. For example, locking member 110 is
illustrated as
having threads that cooperate with corresponding internal threads in receiving
aperture 182.
Retaining member 114 is positioned within channel 186 so as to extend above
the threads of
locking member 110 such as locking member 110 is being removed from receiving
aperture
182, threads come into contact retaining member 114, thereby preventing
complete removal
of locking member 110 from handle portion 170.
23
CA 3010024 2018-06-28
õ -
[00115] An access opening 188 is formed through proximal end 166. Access
opening 188
extends through handle portion 170. In one exemplary arrangement, access
opening 188 may
be provided with an inwardly extending chamfer 189 that tapers toward access
opening 188.
Chamfer 189 provides a self-directing feature for inserting navigation member
112 into
access opening 188. Access opening 188 is in communication with a first
channel segment
191 that extends through handle portion 170 and into body portion 168.
[00116] As seen in FIG. 8D, obturator 104 may further be configured to receive
a viewing
member 167 operatively connected thereto. More specifically, conical tip
portion 172 may
be configured with one or more viewing windows 169 that are oriented to be
flush with the
surface of conical tip portion 172. Viewing windows 169 are in communication
with a
viewing member channel 171 that may selectively receive a viewing member such
as, for
example, a fiber optic cable or an ultrasound probe. The viewing member may be
in addition
to the use of navigation member, or in place thereof. The viewing member
permits the
surgeon to observe, in real-time (i.e., during insertion), surrounding tissue
and eloquent tissue
structures so as to minimize trauma during insertion.
[00117] Body portion 168 extends between distal end 106 and proximal end 166.
Body
portion 168 includes one or more elongated void areas 190. Void areas 190
serve to reduce
weight of obturator 104, thereby making obturator 104 easier to manipulate
during surgical
procedures. Void areas 190 also facilitate sterilization of obturator 104 by
moisture retention
within body portion 168 of obturator 104. Further, void areas 190 also provide
venting,
thereby preventing a vacuum from being generated as obturator 104 is being
withdrawn from
outer sheath 102 during operation.
[00118] Void areas 190 are separated by web portions 192 that extend axially
through a
portion of the length of body portion 168. Disposed on web portions 192 of
body portion 168
are one or more indicators 194. Indicators 194 may include spaced apart hash
marks
24
CA 3010024 2018-06-28
(designated as 194A) that cooperate with an imaging modality to provide
information, in real-
time, concerning the location of obturator 104 relative to various tissue,
critical structures,
and fascicles within the brain, while obturator 104 is positioned within
tissue. Indicators 194
also assist with providing information to regarding the relative positions
between obturator
104 and outer sheath 102. Indicators 194 produce a signal void or minimal
artifact under
certain imaging modalities.
[00119] Body portion 168 may further include one or more cross webs 196. Cross
webs
196 are oriented transverse to web portions 192 and connect web portions 192
together. In
one exemplary arrangement, body portion 168 includes at least one cross web
196 that
operatively defines the outer diameter D2 of body portion 168. Diameter D2 is
sized to fit
within lumen 148 of outer sheath 102 such that obturator 104 and outer sheath
102 may be
selectively slid relative to one another. However, diameter D2 is also sized
to minimize or
even eliminate any gaps between an inner surface of outer sheath 102 and an
outer surface of
obturator 104. In the exemplary arrangement shown in FIG. 7-9, three cross
webs 196A,
196B and 196C are provided. A first cross web 196A is connected to distal tip
portion 172,
while second cross web I96B is spaced proximally from first cross web 196A and
separated
by a void area 193. Third cross web 196C is separated from second cross web
196B by void
areas 192 and is positioned distal from first stop member 176 of handle
portion 170. Cross
webs 196 serve to provide for structural integrity of obturator 104, as well
as improved
rigidity.
[00120] In one exemplary arrangement, one or more of cross webs 196 may
further be
provided with an annular compensating protuberance 197 to accommodate for
slight
manufacturing variations of the diameter of lumen 148 of outer sheath 102. For
example, as
it is contemplated that outer sheath 102 may be a component that is molded
from a resin, a
process which may produce such slight manufacturing variations.
Compensating
CA 3010024 2018-06-28
protuburance 197 extends slightly radially outwardly from an outer surface of
obturator 104
and cooperates with lumen 148 of outer sheath 102 to create a friction fit
between the outer
surface of obturator 104 and lumen 148, due to the slight flexibility of the
resin of outer
sheath 102. Use of compensating protuberance 197 thereby reducing the need for
maintaining a high dimensional tolerance of outer sheath 102 in production.
[00121] In one embodiment, cross web 196B is provided with a second channel
segment
198 (shown in phantom) that extends there through. Second channel segment 198
is axially
aligned with first channel segment 191 and is configured to selectively
receive navigation
member 112. In one exemplary arrangement, disposed in first cross web 196A is
an inwardly
extending depression 199, as best seen in FIG. 9B. Depression 199 is
configured in such a
manner so as to align a distal tip of navigation member 112 with distal end
108 of outer
sheath 102, when outer sheath 102 is assembled to obturator 104.
[00122] Referring
to FIGS. 11A-11F, details of an optional illuminating ring 300 will now
be described. Illuminating ring 300 is generally defined by a top surface
portion 302, a wall
member 304. A circuit board 306 may also be provided. Top surface 302 includes
at least
one access opening 308 therethrough that is configured to receive one or more
surgical
instruments, as will be described below in further detail. Additional small
openings 309 may
be provided in top surface 302. One or more of small openings 309 are
configured to be
aligned with small openings 150 disposed on flange member 142. Wall member 304
extends
from top surface 302 so as to create an open cavity 310 within illuminating
ring 300. An
outer surface of wall member 304 may be textured (not shown), similar to grip
ring 120.
[00123] One or more light elements 312 that are supported by a portion of
illuminating
ring 300. In one embodiment, shown in FIG. 11E, lights 312 are fixedly mounted
to top
surface 304 so as to face inwardly toward open cavity 310, adjacent access
opening 308.
Each light 312 is electrically connected to a remote power source (not shown)
by wires 314.
26
CA 3010024 2018-06-28
In one exemplary arrangement, wires 314 may be retained within channels formed
in top
surface 302 around access opening 308.
[00124] In an alternative arrangement (FIG. 11F), lights 312 may be
incorporated in a
circuit board 306. Circuit board 306 is configured with an access opening 316
that may be
aligned with access opening 308 formed in top surface 302. Further, circuit
board 306 is also
sized to be positioned within open cavity 310, and fixed thereto. In other
words, in one
arrangement, circuit board 306 is sized to have an outer diameter that is
smaller than an inner
diameter defined by wall member 304. A wall opening 318 may be formed through
a portion
of either top surface 302 or wall member 304 to provide access for wires 320
to electrically
connect circuit board 306 to a power source. An example of wall opening 318
may be seen
in FIGS. 11B, 11D, and 11F. Circuit board 306 may be configured such that
there is a
constant output of light when illuminating ring 300 is turned on so that there
is a steady state.
[00125] An exemplary circuit design 321 is depicted in FIG. 11G for circuit
board 306. In
the exemplary configuration, circuit design 321 is configured to prevent
flickering of lights
312 and/or prevent operation of less than all of the lights 312 during use of
illuminating ring
300. More specifically, circuit design 321 is configured such that if one
light 312 burns out,
or if batteries that supply power to circuit get low, illuminating ring 300
will simply shut off
and a replacement battery pack (not shown) may be used.
[00126] In one exemplary arrangement, lights 312 are LED lights, although
other light
devices may be utilized. LED lights do not contribute significantly to the
weight of surgical
access assembly 100, and also dissipates a non-clinical significant amount of
heat. Moreover,
LED lights can emit different combinations of colors/frequencies of light that
may be
incorporated to illuminating ring 300, to provide improved visualization of
fluorescing dyes
which allow for the differentiation of tissues.
27
CA 3010024 2018-06-28
[00127] Use of LED lights also allow for an endoscope to be used with surgical
access
assembly 100, but without an accompanying fiber-optic light source. This
arrangement
significantly reduces a required overall outside diameter of the endoscope,
which improves
the working space within lumen 148 of outer sheath 102. More specifically,
lumen 148 of
outer sheath 102 has more available working space, thereby providing increased
simultaneous
use of multiple instrumentation, as well as improved visualization. Further,
because
traditional endoscope devices must be attached to a supporting structure that
is fixed to an
introducer cannula, the weight of such an assembly tends to pull on the
introducer cannula, in
one direction. This action can compromise the placement of the introducer
cannula during
the procedure and/or cause trauma to brain tissue. Thus, by incorporating
illuminating ring
300 to outer sheath, such potential disadvantages may be avoided.
[00128] While
illuminating ring 300 may be secured to grip ring 120 of outer sheath 102
in any suitable manner, in one exemplary arrangement, illuminating ring 300 is
provided with
a selective locking arrangement to selectively fix illuminating ring 300 to
grip ring 120. In
one exemplary arrangement, wall member 304 is provided with a locking channel
322, best
seen in FIG. 11B. Locking channel 322 comprises wall opening 318 and that
opens into a
first channel segment 324, and a second channel segment 326 that is in
communication with
first channel segment 324. Wall opening 318 extends from a bottom surface 328
of wall
member 304. Second channel segment 326 is spaced upwardly from bottom surface
328 of
wall member 304 and is oriented at an angle from first channel segment 324. In
one
exemplary arrangement, second channel segment 326 is oriented 90 from first
channel
segment 324.
[00129] Locking channel 322 cooperates with locating member 262 to selectively
secure
illuminating ring 300 to grip ring 120. More specifically, illuminating ring
300 is pushed
down over grip ring 120 with locating member 262 entering wall opening 318. As
28
CA 3010024 2018-06-28
illuminating ring 300 is pushed downwardly, locating member 262 travels
through first
channel segment 324. Once locating member 262 contacts a terminal end 330 of
first channel
segment 324, illuminating ring 300 is rotated relative to outer sheath 102
such that locating
member 262 moves into second channel segment 326, thereby selectively locking
illuminating ring 300 to outer sheath 102, as shown in FIG. 12. Once
connected, illuminating
ring 300 thereby provides a hands-free light source to illuminate lumen 148 of
outer sheath
102.
[00130] In one exemplary arrangement, certain segments of outer sheath 102 may
be
frosted so as to reflect light to increase visualization within outer sheath
102. For example,
tapered portion 130 may be frosted. Similarly, the top of grip ring 120 may
also be frosted.
[00131] Referring to FIGS. 11H-1, an alternative arrangement of
illuminating ring 350 is
shown. Illuminating ring 350 is similar to illuminating ring 300 and common
elements, such
as top surface 302, wall member 304, access opening 308, open cavity 310,
small openings
309, and wall opening 318, are also shown in FIGS. 11H-I. The embodiment shown
in FIGS.
11H-I further includes outwardly extending flange members 352. In one
arrangement, flange
members 352 are integrally formed with the outer periphery of illuminating
ring 350. While
the depicted embodiment includes three flange members 352 spaced equi-
distantly about a
periphery of a wall member of illuminating ring 300, it is understood that any
number of
flange members 352 may be provided. Further, flange members 352 may be
arranged about
the periphery in any arrangement.
[00132] Flange members 352 support sensors 354 (see FIG. 111) or reflective
balls that
serve as position indicators. More specifically, sensors 354 arc configurable
to cooperate
with a navigation system (to be explained in further detail below), to
indicate the location of
outer sheath 102 after insertion into an area of interest, once illuminating
ring 300 is
connected to outer sheath 102. In one arrangement, sensors 354 may be molded
into or
29
CA 3010024 2018-06-28
bonded onto flange members 352. In another arrangement, sensors 354 may be
temporarily
attached to flange members 352. For example, flange members 352 may each
include a
groove into which a sensor may be positioned, and a retaining ring may be
secured over each
sensor 354 to temporarily secure sensor to flange member 352.
[001331 In another exemplary arrangement, sensor 354 may be powered through
circuit
board 306. More specifically, sensors 354 may be electrically connected to
circuit board 306.
Additional wires electrically connect circuit board 306 to a power source to
provide power
not only to lights carried by illuminating ring 350, but also to sensors 354.
[00134] In yet another alternative arrangement, a support ring (not shown)
that may be
selectively mounted to grip ring 120 of outer sheath 102 may also be provided.
The support
ring is configured to extends at least partially around outer sheath 102 and a
navigational
element, such as an RFID chip or sensor may be secured thereto. Similar to the
illuminating
ring 350, when the support ring is secured to the outer sheath 102, the
location of outer sheath
102 may be "read" by the navigational system. In another arrangement, the
support ring may
be configured to support reflective elements, such as reflective balls.
Support ring may
alternative be configured to be attached to illuminating ring 300, rather than
outer sheath 102.
[00135] Operation of surgical access assembly will be described in
connection with a
process flow 400 illustrated in FIG. 13. Generally speaking, before any
surgical procedure is
decided upon, a patient will first present with symptoms or deficits requiring
evaluation.
Thus, the start of process flow 400 begins with a surgeon making a
determination 402 of the
cause of such neurological symptoms/deficits. Such a determination may be made
through
use of a variety of imaging modalities, including, but not limited to, MRI or
CT imaging.
The process then proceeds to step 404.
1001361 If the determination from step 402 finds that a brain condition is
found, such as a
tumor or hematoma, an additional determination is required. More specifically,
a location of
CA 3010024 2018-06-28
_ .
the brain condition is determined in step 404. If the imaging determines that
an area of
interest is located in the intra-axial/subcortical space, the process flow
continues to step 406.
However, if a brain condition is located in other, more easily accessible
areas of the brain, the
process flow stops.
[00137] As discussed above, any suitable imaging modality may be utilized to
determine if
a brain condition exists, and if so, where that brain condition is located.
FIGS. 14A and 14B
illustrate examples of imaging results from an MRI. More specifically, an area
of interest
500, in this case a tumor, may be seen deep in the subcoritcal space.
[00138] Once area
of interest 500 is located, at step 406 an additional imaging sequence is
employed to determine the location of eloquent structures such as vessels and
fiber tracts and
the associated fascicles so as to plan the safest access route to the area of
interest. Exemplary
arrangements for accomplishing this step include CT-Angiography and MRI with
Diffusion
Tensor Imaging (DTI) sequences. DTI allows for the determination of
directionality as
well as the magnitude of water diffusion along the communication "wiring"
pathways
called fiber tracts and fascicles. This kind of MRI imaging can provide
imaging to allow
for the estimation of potential damage to nerve fibers that connect the areas
of the brain
which can be affected by a stroke, for example, to brain regions that are
distant from it,
and can also be used to visualize white matter fibers in the brain and can map
(trace
image) subtle changes in the white matter associated with diseases such as
multiple
sclerosis and epilepsy, as well as assessing diseases where the brain's wiring
is
abnormal, such as schizophrenia, as well as tumor involvement.
[00139] Diffusion Tensor Tractography (DTT) may also be used. DTT allows for
noninvasive racking of neuronal fiber projections in a living human brain.
White matter
fiber trajectories are reconstructed throughout the brain by tracking the
direction of
fastest diffusion, which is assumed to correspond to the longitudinal axis of
the tract.
31
CA 3010024 2018-06-28
Diffusion tensor tractography provides insight into white matter integrity,
fiber
connectivity, surgical planning, and patients' prognosis. Once the imaging
information
has been analyzed, the process then proceeds to step 408.
[00140] Referring to FIG. 15, an example of DTI imaging of the brain shown in
FIGS.
14A and 14B is depicted. A map of fascicles and other vessels are illustrated
in FIG. 15,
including major vessels 502 that are shown spread around area of interest 500.
Such images
provide the surgeon with valuable information about potential avenues for
access tracts to
area of interest 500.
[00141] In step 408, a plan for the operative trajectory is developed. More
specifically,
imaging information is used to plan (either manually or with software) the
access
tract/pathway to achieve fiber tract involvement during access to the area of
interest. In
evaluating fiber tract involvement from a potential access tract/pathway,
consideration of
fiber tract importance may be based on an individual patient's occupational
and personal
needs and/or preference. Once a pathway has been planned, the process proceeds
to step 410.
[00142] In step 410, image data from the MRI/DTI and CT/CTA image sequence
obtained
during step 406 is input into an intraoperative navigation system.
Intraoperative navigation
systems may be used to provide direct visualization of area of interest 500 in
real time, as
surgical access system 100 is being positioned within the brain. The method
then proceeds to
step 412.
[00143] Once the procedure has been planned and the image data has been
uploaded to a
navigational system, step 412 requires that the appropriate sized surgical
access assembly 100
is selected. First the appropriate size of a craniotomy must be determined.
Further, the
present disclosure contemplates that different diameter and length sizes of
surgical access
assembly 100 may be employed, the size depending on the particular location of
area of
interest 500. Accordingly, step 412 requires that the surgeon select the
appropriate length
32
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and diameter of surgical access system 100 to be used, based on the physical
and location
characteristics of the area of interest 500. Once surgical access assembly 100
is selected, the
process proceeds to step 414.
[00144] In step 414, the surgeon creates the craniotomy and Dural access
incision. The
process then proceeds to step 416.
[001451 In step 416, the obturator 104 is inserted into outer sheath 102
until grip ring 120
abuts first stop member 176, as shown in, for example FIG. 2. Navigation
member 112 is
then operatively connected to obturator 104.
[00146] As discussed above, various types of navigation members 112 may be
employed
with surgical access assembly 100. In one exemplary configuration, navigation
member 112
is configured as a probe (as shown in FIG. 2). In this configuration,
navigation member 112
is inserted through access opening 188 of grip member 178 until a distal tip
417 of navigation
member 112 is deposited into depression 199 (see FIG. 9B). Depression 199 is
formed so
that distal tip 471 of navigation member 112 is positioned within the same
plane as distal tip
132 of outer sheath 102, when obturator 102 and outer sheath 104 are assembled
together as
shown in FIG. 2. Locking member 110 may be tightened to fixedly retain
navigation
member 112 within obturator 102. A portion of navigation member 112 will
extend
proximally from grip member 178 and will be operatively connected to a
navigation system
that includes a screen that visually illustrates the information obtained from
the imaging
sequences, along with the trajectory of surgical access system 100. Thus, with
the navigation
member 112 operatively connected to a navigation system, the position of
distal tip 132 of
outer sheath may be indicated, in real time, while surgical access system 100
is being
navigated within a body.
[00147] In another configuration, the software operating the navigation system
may further
be provided with an offset dimension that corresponds to a distance D3 between
distal tip 174
33
CA 3010024 2018-06-28
of obturator 104 and distal tip 132 of outer sheath. In this arrangement, a
dotted line may
appear on the navigation screen that indicates where distal tip 174 of
obturator 104 is located,
in real-time.
[00148] Navigation member 112 may further be provided with image guidance
position
indicators, such as an array of reflectors of the type use in connection with
optical image
guidance systems. The infrared reflectors used with such a system are mounted
to a handle of
a probe-like navigation member 112 in a customary triangular configuration
calibrated to
identify the tool to the image guidance system. Such imaging systems are
available, for
example Medtronic Surgical Navigation Technologies (Denver, Colo.), Stryker
(Kalamazoo,
Mich.), and Radionics (Burlington Mass.).
[00149]
Typically, the positioning of the indicators is calibrated such that the image
guidance system can project an image of the tool onto a display of images of
the patient's
brain, such as MRI images used to plan surgery. Thus, as discussed above, as
surgical access
system 100 is inserted, the surgeon can see the relative position of system
100 relative to the
structures of the brain as reflected on images, and particularly with respect
to the target
tissue.
[00150] Other guidance systems, such as magnetic or electromagnetic or radio
transmitting
systems may also be used, and the illustration of infrared reflectors and
discussion of optical
image guidance systems are exemplary only and are not intended to be limiting.
In addition,
while the exemplary method has been described in connection with superimposing
an image
of surgical access system 100 onto a pre-operative image, it is contemplated
that real-time
imaging capability may be utilized and that the image of surgical access
system 100 may then
be shown in relation to the surrounding tissue structures on a real time
image.
[00151] In another exemplary configuration, an RFID chip may be embedded in
obturator
104 that operatively communicates information to a navigation system or other
surgical
34
CA 3010024 2018-06-28
,
system about the specific attributes, such as, but not limited to, length and
diameter. This
information may be used to facilitate placement with the navigation system or
other systems
for information display or trajectory and location calculations during
placement of obturator
104.
[00152] In yet another exemplary arrangement, as shown in FIGS. 16A-16B, an
alternative
embodiment of an obturator 504 may be used, wherein the obturator 504 is
configured with a
post 512 that is configured to operatively attach a navigation array. Post 512
may be
detachably or permanently connected to grip member 578 of obturator 104. For
example, as
shown in FIG. 16A, post 512 is configured to be selectively detachable and may
be used to
capture a small coil 513 for MRI tracking of surgical access assembly 100. A
portion of post
512 may be threaded and an access opening 588 formed in a proximal face of
grip member
578 have be provided with corresponding threads (not shown) so as to affix
post 512 to
obturator 504. Other manners of selectively affixing post 512 to obturator 504
are also
contemplated, including, but not limited to, a locking member 110 arrangement
similar that
shown in FIG. 2. As also discussed, post 512 need not be selectively
detachable. Indeed, it is
contemplated that post 512 may be permanently affixed to obturator 504, in any
suitable
manner, whereby the navigation array may be secured to post 512. In yet
another alternative
arrangement, obturator 504 may be configured such that a post, which is an
element of the
array itself, may be attached.
[00153] In still
a further alternative arrangement, referring to FIGS. 16C-16D, a coil
sensor 513' may be configured to be disposed about an outer periphery of post
512. In this
arrangement, coil sensor 513' is slid or otherwise mounted to post 512 such
that when post
512 is operatively attached to obturator 504 coil sensor 513' is captured
between a portion of
grip member 578 and a proximal end portion 514. A connecting wire 516
operatively
attaches coil sensor 513' to an image position console 518.
CA 3010024 2018-06-28
[00154] Once surgical access assembly 100 is assembled and operatively
connected to a
navigational system, the process then proceeds to step 418, in which surgical
access assembly
100 is navigated to area of interest 500. In one exemplary arrangement, distal
tip 178 of
obturator 104 is directed to a furthermost outer margin of area of interest
500. More
specifically, referring to FIG. 14B, for example, surgical access assembly 100
is directed
along a trajectory T that extends through area of interest 500 to a location
501 that may be
positioned within the margins of area of interest 500 or even slightly beyond
the margin.
[00155] Due to
the tapered configuration and closed, radiused distal tip 174 of obturator
104, as well as the radiused distal tip 132 of outer sheath 102, as surgical
access assembly
100 is inserted into the brain and navigated to area of interest 500, tissue
is gently pushed to
either side of surgical access assembly 100, so as to atraumatically dilate
tissue, while
minimizing trauma to the tissue. Further, because surgical access assembly 100
is
operatively connected to navigation member 112, as surgical access assembly
100 is being
inserted into the brain tissue, navigation member 112 may cooperate with an
imaging
modality to providing real-time information concerning fiber tact in
trajectory T, thereby
allowing the surgeon to minimize fiber tract compromise or damage during
insertion of
surgical access assembly 100. Once surgical access assembly 100 is positioned
at area of
interest 500, the process proceeds to step 420.
1001561 As step 420, navigation member 112 removed from or detached from
surgical
access assembly 100. The process then proceeds to step 422.
1001571 Once navigation member 112 is removed, outer sheath 102 is then
operatively
positioned with respect to area of interest 500. More specifically, as shown
in FIG. 17A,
outer sheath 102 is decanted with respect to obturator 104 such that distal
end 108 of outer
sheath 102 is moved toward distal end 106 of obturator 104, as indicated by
arrow M. This
action is accomplished by grasping grip ring 120 with one hand while
maintaining obturator
36
CA 3010024 2018-06-28
104 stationary, such, for example, grasping grip member 178 with another hand.
Grip ring
120 may be gently rotated and/or swiveled with respect to a central axis of
obturator 104 to
enable outer sheath 102 to be moved distally with respect to obturator 104.
First stop
member 176 aids in gripping and manipulating outer sheath 102, in that a gap
423 (see FIG.
2) is created between end surface 158 and a distal end surface of grip member
178. Outer
sheath 102 is decanted until grip ring 120 aligns with indicator 194A (see
FIG. 7A).
Indicator 194A is spaced from first stop member 176 a distance that generally
corresponds to
the length of distal tip portion 172 of obturator 104. Accordingly, when grip
ring 120 is
aligned with indicator 194A, distal end 108 of outer sheath 102 is aligned tip
member 174 of
obturator 104. Moreover, outer sheath 102 is positioned within area of
interest 500. The
process then proceeds to step 424.
[00158] In step
424, once outer sheath 102 is appropriately positioned, obturator 104 is
then removed from outer sheath 102, as shown in FIG. 17B. More specifically,
outer sheath
102 is maintained to be relatively stationary at area of interest 500, and
obturator 104 is
moved in a proximal direction until fully removed from outer sheath 102. This
action results
in outer sheath 102 forming a pathway to area of interest 500; a pathway that
not only
circumvents the need to cross the blood brain barrier for the delivery of
therapy, but also
provides direct access to the area of interest within the patient.
[00159] In other embodiments, rather than provide obturator 104 with
navigation member
112, or in addition to providing obturator 104 with navigation member 112, as
discussed
above, outer sheath 102 may be provided with and RFID chip or sensor. With
this
configuration, the RFID chip or sensor of outer sheath 102 cooperates with the
navigation
system thereby making outer sheath 102 visible to the user on the navigation
system,
independent of obturator 104. Thus, once obturator 104 is removed from outer
sheath 102,
37
CA 3010024 2018-06-28
the location within the patient of outer sheath 102 will still be visible to
the navigation
system.
[00160] More specifically, the navigation system works with the additional
images taken
during the imaging sequence in step 406. The images taken in step 406 are
uploaded into the
intraoperative navigation system, as indicated in step 410. The RFID chip
and/or sensors are
configured to be read by the navigation system and place an image of outer
cannula 102,
thereby allowing the surgeon to direct visualize the location of outer cannula
102, while
positioned within the patient.
[00161] Once
outer cannula 102 is positioned at the area of interest 500 and obturator 104
is removed, one of the illuminating rings 300,350 may be attached to outer
sheath 102.
1001621 In one exemplary arrangement, rather than employing an RFID chip
and/or sensor
in outer sheath 102, illuminating ring 350 may be provided with sensors or
reflective balls, as
described above in connection with FIGS. With
this type of configuration, once
obturator 104 and outer sheath 102 have been delivered to area of interest 500
and obturator
104 is removed from outer sheath 102, illuminating ring 350 is operatively
connected to outer
sheath 102. Because illuminating ring 350 includes a navigational element,
such as sensors
and/or reflective balls, once illuminating ring 350 is connected to outer
sheath 102, the
navigation system will be able to "read" where outer sheath 102 is located in
the body. In
other words, an image of outer sheath 102 will be able to be projected onto
the static images
uploaded into the navigational system.
[00163] Once
outer sheath 102 is placed in its desired location, the process then proceeds
to step 426.
[001641 In step
426, outer sheath 102 is then secured in place so as to prevent cranial
pressure or general manipulation of instruments passing in and out of the
sheath 102 from
pushing or dislocating outer sheath 102 out of the brain tissue. In one
exemplary
38
CA 3010024 2018-06-28
arrangement, a securing member may be utilized with small openings 150 on grip
ring 120 to
temporarily secure outer sheath 102. For instances where illuminating ring 300
is used with
surgical access assembly 100, small openings 309 in illuminating ring 300
align with small
openings 150 of grip ring. Accordingly, securing members may also be utilized
with small
openings 309. However, the securing member may be secured so as to permit a
limited
degree of movement, as will be discussed below, so as to result in a floating
system that
permits selective repositioning. Suitable securing members include, but are
not limited to,
bridle sutures, flexible bands with retaining hooks, or even repositionable
retractor arms.
Additional alternative securing arrangements are disclosed below in paragraphs
[0139-0151].
Once outer sheath 102 is secured, the process then proceeds to step 428.
1001651 In step 428, debulking area of interest 500 may be conducted.
Traditionally, a
patient is given medication, such as, for example, Mannitol, before an
intracranial operation
to reduce intracranial pressure (ICP) of the brain prior to the surgery.
Indeed, ICP is often
experienced by patients due to the natural response of the craniotiomy and/or
the present of
an abnormality within the brain. The present inventors have found that it may
be
advantageous to omit or minimize the use of medication for reducing ICP. More
specifically,
by not reducing ICP, because the brain tends to occupy the available space
within the skull,
after obturator 104 is removed from outer sheath 102, the target tissue may
have a tendency
to flow into, and present itself into the open distal end 108 of outer sheath
102, due to the
cranial pressure. Area of interest 500 may actually move into outer sheath 102
on its own,
thereby assisting in the delivery and minimizing manipulation required of
outer sheath 102
during the process.
1001661 It is contemplated that a wide range of surgical devices may be
inserted into outer
sheath 102 to remove tissue abnormalities. In one exemplary arrangement, it is
contemplated
that outer sheath 102 may have an inner diameter up to approximately 20 mm, to
allow
39
CA 3010024 2018-06-28
multiple instruments, such as graspers, dissectors, scissors, cautery and
suction instruments to
be inserted through outer sheath 102 to perform surgery.
1001671 One exemplary surgical device that may be used is the NICO MYRIAD
manufactured and distributed by Nico Corporation of Indianapolis, Indiana.
Referring to
FIG. 18, an exemplary surgical cutting device 640 is shown, such as that
disclosed in co-
pending, and co-owned with the assignee of the present application, U.S.
Patent Appl. Serial
No. 12/389,447.
Surgical
cutting device 640 includes a handpiece 642 and a cutting element that
includes an outer
cannula 644 and an inner cannula (not shown). In one exemplary configuration,
handpiece
642 is configured with a generally cylindrical shape. Handpiece 642 may be
sized and
shaped to be grasped with a single hand. Handpiece 642 also includes a lower
housing 650
comprising a proximal section 646 and a distal section 648. A front housing
section 655
may be connected to a cam housing positioned in distal section 648. An upper
housing 652 is
also provided. The cutting element is mounted to upper housing 652 and may be
fluidly
connected to a tissue collector 658. In one exemplary arrangement, tissue
collector 658 may
be operatively connected directly to upper housing 652. Alternatively, tissue
collector 658
may be remotely connected to the cutting element by appropriate tubing. A
vacuum line (not
shown) may be connected to a proximal end of tissue collector 658 to direct
tissue into the
cutting element, as well as to deliver severed tissue to tissue collector 658.
A rotation dial
660 for selectively rotating the outer cannula 644 with respect to handpiece
642 is also
mounted to upper housing 652, to provide controlled cutting action.
1001681 Use of surgical device 640 is advantageous in that space is limited to
effectuate
tissue debulking, such that use of traditional surgical scissors may be
challenging, especially
when other instruments are inserted into outer sheath 102 simultaneously.
Moreover,
fibrosity of a tumor may present challenges for the use traditional suction
debulking devices.
CA 3010024 2019-11-08
Traditional graspers operate by tearing tissue of interest. However, the
tearing action may
become problematic if vessels or fascicles are too close to the tissue being
torn in that such
vessels or fascicles may also be torn.
[001691 In step 428, as area of interest 500 is cytoreductively debulked, it
may become
necessary to reposition or move outer sheath 102. If repositioning is
necessary, the process
moves to step 432. To that end, in one exemplary arrangement, manipulation
members may
be provided. Examples of manipulation members 700 and 700' are illustrated in
FIGS. 19A-
19B. Manipulation member 700 comprises a handle member 702 that supports an
armature
704, and a hook element 706 that extends from armature 704. Hook element 706
is sized to
fit within small openings 150 and 309 disposed within grip ring 120 and
illuminating ring
300, respectively. In operation, hook element 706 is engaged with a small
opening 150/309
and handle member 702 is used to gently push or pull outer sheath 102. Because
outer sheath
102 is only loosely secured, outer sheath 102 may be selectively moved
slightly for improved
visualization or to access tissue. After outer sheath 102 has been
repositioned, or if
repositioning of outer sheath 102 is not necessary, the process moves to step
434, and
cytoreduction of area of interest 500 continues.
[00170] In an alternative arrangement, manipulation member 700' may be secured
to a
flexible holder member 710. Manipulation member 700' comprises an armature 712
that
carries a hook element 714 and an engagement portion 716. Engagement portion
716
operatively engages holder member 710 so as to fixedly secure manipulation
member 700' to
holder member 710, thereby freeing a surgeon's hand, once outer sheath 102 is
positioned. It
is understood that multiple manipulation members 700/700' may be utilized to
permit a
surgeon to selectively push or pull outer sheath 102.
1001711 Referring to FIGS. 19C-19F, other alternative arrangements for
holding outer
sheath 102 during a procedure are shown. More specifically, FIGS. 19C-19D
illustrate a
41
CA 3010024 2018-06-28
holding arrangement 720 that may be used with a Greenberg retractor assembly.
Holding
arrangement 720 comprises body portion 722, an engagement barrel 724, and a
retaining
member 726.
1001721 Body portion 722 may be configured as a relatively thin shaft. In one
exemplary
arrangement, body portion 722 includes at least two bend points 728a and 728b
that are
separated by a section of shaft 730. Bend point 728a is positioned proximal of
a distal end of
body portion 722, defining a retaining section 732. Bend point 728b is
positioned proximal
of shaft section 730. Bend point 728b and a proximal end 734 cooperate to
define a proximal
shaft section 736. Bend points 728a and 728b serve to axially space retaining
section 732
from proximal section 734. In one arrangement, as shown in FIG. 19D, shaft
section 730 is
disposed at an approximately 45 angle. In another exemplary arrangement (not
shown),
shaft section 730 may be oriented at an approximately 900 angle. It is also
contemplated that
shaft section 730 may be deposed at other angles. In some exemplary
arrangements, bend
points 728a, 728b may be eliminated such that retaining section 732 and
proximal section
736 are arranged along a common axis. Retaining section 732, shaft section 730
and
proximal section 736 may be integrally formed together, or constructed as
separate elements
that are connected together.
[001731 Retaining section 732 terminates at its distal end 738 in retaining
member 726.
As best seen in FIG. 19C, retaining member 726 is configured as a shepherd's
hook that is
configured to curve back toward retaining section 732, but defining a gap 740
between an end
742 of retaining member 726 and retaining section 732. Retaining member 726
may be
integrally formed with retaining section 732, or formed as a separate
component that connects
with retaining section 732. Retaining member 726 is configured similar to a
spring clip such
that retaining member 726 snaps partially around outer sheath 102.
42
CA 3010024 2018-06-28
1001741 Mounted on proximal section 736 is engagement barrel 724. Engagement
barrel
724 is configured for selectively rotation about proximal section 736. In one
exemplary
arrangement, on either end of engagement barrel 724, stop members 744 are
disposed. In
operation, engagement barrel 724 is positioned within Greenberg adapter and
clamped
thereto. Stop members 744 serve to prevent engagement barrel 724 from being
unintentionally extracted from the Greenberg adapter. However, due to the
configuration of
engagement barrel 724 and placement of stop members 744, engagement barrel 724
is
permitted to move a predetermined amount in a linear fashion. Moreover,
because
engagement barrel 724 is configured to selectively rotate about proximal
section 736, outer
sheath 102 may be selectively pivoted along the Y direction to a desired
position. Further,
because retaining member 726 is configured as a shepherd's hook with the gap
740, outer
sheath 102 may be pivoted in the X direction. Thus holding arrangement 720
allows for
selective positioning of outer sheath 102.
1001751 An alternative holding arrangement 750 is shown in FIGS. 19E-19F.
Holding
arrangement 750 is configured to be used with a Sugita adapter (not shown).
Holding
arrangement 750 is similar to holding arrangement 720 comprises body portion
752, an
engagement barrel 754, and a retaining member 756.
100176] Body portion 752 may be configured as a relatively thin shaft and may
include
one or more bend points 758a-758b. Like holding arrangement 720, bend points
758a, 758b
serve to axially offset a retaining section 762 from a proximal section 764. A
shaft section
760 is positioned between bend points 758a, 758b.
1001771 Retaining section 762 terminates at its distal end 768 in retaining
member 756.
As best seen in FIG. 19E, retaining member 756 is configured as a shepherd's
hook that is
configured to curve back toward retaining section 762, but defining a gap 770
between an end
772 of retaining member 756 and retaining section 762. Retaining member 756
may be
43
CA 3010024 2018-06-28
integrally formed with retaining section 762, or formed as a separate
component that connects
with retaining section 762. Retaining member 756 is configured similar to a
spring clip such
that retaining member 756 snaps partially around outer sheath 102.
[00178] Mounted on proximal section 764 is engagement barrel 754. Engagement
barrel
754 is configured for selectively rotation about proximal section 764. A
mounting member
774 is fixedly secured to engagement barrel 754. Mounting member 774 is
configured to be
received within a Sugita clamp mechanism. In one exemplary arrangement, on a
distal end of
engagement barrel 754, a stop member 776 is disposed. In operation, engagement
barrel 754
is positioned within the Sugita adapter and clamped thereto. Stop member 776
serves to
prevent engagement barrel 754 from being unintentionally extracted from the
Sugita adapter.
However, due to the configuration of engagement barrel 754 and placement of
the stop
member 776, engagement barrel 754 is permitted to move a predetermined amount
in a linear
fashion. Moreover, because engagement barrel 754 is configured to selectively
rotate about
proximal section 764, outer sheath 102 may be selectively pivoted along the Y
direction to a
desired position. Further, because retaining member 756 is configured as a
shepherd's hook
with the gap 770, outer sheath 102 may be pivoted in the X direction. Thus
holding
arrangement 750 allows for selective positioning of outer sheath 102.
[00179] Yet another alternative arrangement of a holding arrangement 780 is
shown in
FIGS. 19G-19J. Holding arrangement 780 is configured to maintain longitudinal
alignment
of an exoscope 782 and outer sheath 102. In this arrangement, light is
provided to outer
sheath 102 (and hence to the surgical site/area of interest) via exoscope
(Karl Storz
Endoscopy, Germany) 782. Thus, while exoscope 782 is spaced apart from outer
sheath 102,
an effective visual line of sight and maintenance of projection of light to
the bottom of outer
sheath 102 may be achieved.
44
CA 3010024 2018-06-28
[00180] Holding arrangement 780 is provided with an alignment tool 784.
Alignment tool
784 is configured with an outwardly extending arc portion 786. More
specifically, outwardly
extending arc portion 786 arcs away from a longitudinal axis LA that passes
through a
longitudinal space between exoscope 782 and outer sheath 102, when exoscope
782 and outer
sheath 102 are aligned. In this manner, arc portion 786 cooperates with
exoscope 782 and
outer sheath 102 to define a working space between exoscope 782 and outer
sheath 102. This
arrangement permits a user to be able to pass instruments in and out of outer
sheath 102, as
well as the area of interest.
[00181] In one exemplary arrangement, arc portion 786 is defined by a pair of
wire-like
members 786a, 786b (best seen in FIG. 19H). Members 786a, 786b are configured
to be
substantially rigid so as to maintain the position of outer sheath 102 with
respect to exoscope
782.
[00182] In addition to arc portion 786, alignment tool 784 further includes
a exoscope
attachment harness 788 and an outer sheath attachment arrangement 790.
Exoscope
attachment harness 788, best seen in FIG. 19H, is comprised of a retaining
mechanism 792
attached to a reinforcement section 794. Reinforcement section 794 extends
upwardly in the
same direction as longitudinal axis LA from members 786a, 786b. Retaining
mechanism 792
is configured to at least partially extend around an outer periphery of
exoscope 782 in a snap-
fit or clamping arrangement. In one exemplary arrangement, retaining mechanism
792 is
integrally formed with reinforcement section 794. Similarly reinforcement
section 794 may
also be integrally formed with arc portion 786. A bend point 795 joins arch
portion 786 with
reinforcement section 794.
[00183] As best seen in FIG. 191, outer sheath attachment arrangement 790
includes
connector members 796a, 796b that are configured to be received within
openings formed in
grip ring 120, sufficiently spaced apart such that alignment tool 784 may
maintain a desired
CA 3010024 2018-06-28
position. In one exemplary arrangement, connector members are pins that are
joined to
members 786a, 786b by bend points 797a, 797b. With this arrangement, outer
sheath 102
may be selectively pivoted about longitudinal axis LA, thereby allowing some
degree of
flexibility in positioning outer sheath 102 at the area of interest.
[00184] Referring to FIG. 19J, an alternative arrangement for connecting arc
portion 786
to outer sheath 102 is shown. In this arrangement, an end of one of the
members 786a is
configured as a shepard's hook 798, similar to that shown in the arrangements
of FIGS. 19C
and 19E. As explained above, this arrangement allows the outer sheath 102 to
be pivoted in
the X direction, thereby permitting selective positioning of outer sheath 102.
[00185] Outer
sheath 102 is configured such that multiple instruments may be inserted
simultaneously therewithin, thereby increasing the speed and safety of
surgical procedures.
In one exemplary arrangement, an endoscope may be partially inserted and held
to one side
of outer sheath 102, to provide an image of area of interest 500 to a monitor,
while a surgical
instrument, such as surgical instrument 640 is also inserted within outer
sheath 102.
Illuminating ring 300 may also be used, with the endoscope and the surgical
instrument being
inserted through access opening 308 that aligns with opening 146 of grip ring
120. Because
illuminating ring 300 provides the necessary light tor outer sheath 102, a
relatively small
diameter endoscope may be use, thereby increasing the available space within
outer sheath
102 for other surgical instruments. In another exemplary configuration, the
surgeon may
have both a surgical instrument and a cautery instrument simultaneously
inserted into outer
sheath 102, thereby permitting the surgeon to cauterized vessels that are
encountered during
the procedure.
[00186] In another exemplary arrangement, during the procedure, fluorescing
dye may be
introduced into the patient, either before surgery or during the surgery. One
such dye is
Gliolan (5-Aminolevulinic Acid), however other suitable dyes may also be used.
The
46
CA 3010024 2018-06-28
fluorescing dye may be introduced by any suitable methods, including, but not
limited to,
injecting the patient with the dye, providing the dye orally to the patient
prior to surgery, or
even injecting the dye in situ through outer sheath 102. In one exemplary
arrangement, the
dye is configured to bond to proteins of abnormal cells such that the cells
are visually
distinguishable from healthy cells. With this visual indication of healthy vs.
abnormal tissue,
the surgical instrument may be more efficiently used to resect abnormal
tissue. In other
embodiments, light delivered through outer sheath 102 has a predetermined
wavelength that
is configured to interact with the dye to illuminate or fluoresce abnormal
tissue. For
example, illumination cap 300 may be provided with LED lights of a preselected
wavelength
that operatively interacts with a preselected dye to illuminate abnormal
tissue and assist with
differentiating healthy tissue from diseased tissue.
[00187] In another exemplary configuration, a light probe or fiber optic
bundle (not
shown) may be inserted into outer sheath 102 to assist with differentiation
between healthy
tissue and abnormal tissue. In one arrangement, the probe/bundle is simply
inserted into
outer sheath 102 as a separate element, along with a surgical device. The
probe/bundle is
operatively connected to a console such that the reflected light is delivered
to the console. A
sensor in the console (i.e., the sensor is remotely located from the point of
detection, receives
the reflected light to trigger a signal to the user based on predetermined
parameters. In other
words, the natural florescence of the tissue is then reflected back to the
console to inform the
user whether or not the tissue is diseased or abnormal.
[00188] In another exemplary configuration, the surgical device may be further
provided
with a delivery sleeve 800 that mounts to surgical device 640, and example of
which may be
found in FIG. 20. Various embodiments of delivery sleeve 800 may be found in
co-pending,
and co-owned with the assignee of the present application, U.S. Patent Appl.
Serial No U.S.
Patent Appl. Serial No. 13/269,339 .
47
CA 3010024 2019-11-08
As may be seen in FIG. 20, delivery sleeve 800 generally includes at least two
lumens, a first lumen 802 which is configured to receive outer cannula 644 of
surgical device
640, and a second lumen 804 which is configured to receive an optical device,
such as a light
probe or a fiber optic bundle (not shown). Use of this arrangement permits use
of additional
surgical tools/instruments within outer sheath 102. More specifically, as the
optical device is
supported within the delivery sleeve 800, which, in turn, is connected to the
surgical device,
the surgeon can simultaneously differentiate between abnormal and healthy
tissue, and resect
tissue, all with by just holding the surgical device 640. As a result, the
surgeon may also
choose to utilize a separate cautery device within outer sheath 102 to permit
cauterization of
any vessels during the resection, in real time, and without requiring removal
of the surgical
device 640.
[00189] Because outer sheath 102 may be directly positioned at area of
interest 500 in such
a manner as to avoid unnecessary damage to critical structures, and because
surgical device
640 may be placed directly at the sight of area of interest, utilizing
surgical access system 100
provides the ability to resect most of an area of interest 500, such a tumor.
As one of
ordinary skill in the art can appreciate, the more that a tumor is resected
and removed, the
less therapy is required for treatment. In other words, the more diseased
tissue there is
resected, the less diseased tissue there is to destroy.
[00190] Once a cytoreductive resection of area of interest 500 has been
completed, the
process then proceeds to step 436. In step 436 a decision is made to either
remove outer
sheath 102 or to leave outer sheath 102 in position. More specifically, for
some therapy
applications, removal of outer sheath 102 may be more effective than leaving
outer sheath in
place to deliver the therapy. If the decision is made to remove outer sheath
102, after
removal of outer sheath 102, the process 400 proceeds to step 438.
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[00191] As one of
ordinary skill in the art may appreciate, the natural elasticity of brain
tissue will maintain access or a corridor to area of interest 500 for period
of time. In step
438, while the corridor is still intact after removal of outer sheath 102, in
one exemplary
arrangement, a delivery device may be inserted into the corridor to deliver
irrigation to the
surgical site. In some instances, a syringe may be inserted into the corridor
to deliver an
irrigating fluid, such as saline directly to the surgical site. In
another exemplary
configuration, a drainage catheter (which is configured with a plurality of
small openings at
its distal end) is delivered into the corridor such that the distal end of the
catheter is placed at
or adjacent the surgical site. Irrigating fluid is then introduced into the
proximal end (such, as
for example, by operatively attaching a syringe barrel to the proximal end),
to deliver the
irrigating fluid to the surgical site. The irrigating fluid flushes out debris
and assists in the
brain tissue's natural tendency to close back in on itself. Once the surgical
site has been
irrigated, it may also be desirable to deliver certain therapies directly to
the surgical site,
thereby avoiding therapy delivery and uptake issues traditionally encountered
by systemic
approaches.. For example, certain therapies that may be provided in liquid
form may be
directly injected through the corridor, just prior to the tissue closing back
in on itself.
Because the corridor is closing, the therapy will be held in place at the
surgical site, thereby
increasing its effectiveness at the site and surrounding tissue.
[001921 In some therapy methodologies, outer sheath 102 may be necessary to
aid in the
delivery and/or placement of such therapy, as will be explained in further
detail below.
Accordingly, if the decision in step 436 is made to keep outer sheath 102 in
place after
completion of cytoreduction, the process 400 proceeds to step 442.
1001931 In step
442, area of interest/surgical site 500 is irrigated to again remove any
debris from the area. Irrigation may be performed in the same manner as
discussed in step
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438, except through outer sheath 102. Once irrigation is complete, the process
proceeds to
step 444.
[00194] In step
444 a therapy is delivered to area of interest 500. In one exemplary
configuration, intraoperative radiotherapy (IORT) may be employed, so as to
deliver therapy
directly to area of interest 500 through outer sheath 102. In one exemplary
configuration, an
implantable therapy may be applied to area of interest 500. Example of an
implantable
therapy include: bioabsorbable radiation pellets, wafers or mesh, such as, for
example, those
manufactured by Nano-Rad LLC. Other examples include, but are not limited to,
titanium
capsules or seeds with radiation contents, bioabsorbable gels or foams that
contain
radioactive, chemotherapy or immunotherapy agents.
1001951 In another exemplary configuration, a balloon catheter may be used to
perform
brachytherapy following the removal of diseased tissue at area of interest
500. For example,
a balloon catheter may be inserted through outer sheath 102 and delivered to
area of interest,
and then the balloon catheter may be inserted with a predetermined amount of
radioactive
solution followed by the delivery of radiation to the surrounding tissues. A
commercially
available catheter that may be used includes the GliaSite balloon catheter,
with an lotrex
radioactive solution. Use of a balloon catheter may provide a more targeted
delivery of liquid
radiation, thereby reducing impact on brain tissues surrounding the diseased
tissue.
[00196] In another exemplary arrangement, an electron beam driven X-ray source
may be
provided. One such exemplary configuration is the Zeiss INTRABEAM . The
electrons are
generated and accelerated in a main unit and travel via an electron beam drift
tube which is
surrounded by a conical applicator sheath such that its tip lies at an
epicenter of an applicator
sphere to provide a point source of low energy X-rays at the tip. With this
configuration, a nearly
isotropic field of low energy is emitted.
CA 3010024 2018-06-28
[00197] In
operation, the applicator sheath is inserted through outer sheath 102 and into
the
surgical cavity at area of interest 500. An intraoperative ultrasound may be
performed to
determine the distance of the applicator surface to the skin, to avoid
significant skin doses. The
applicator sheath may be secured into place by the surgeon using subcutaneous
sutures around the
neck of the sphere, similar to that described above in connection with outer
sheath 102.
[00198] In another exemplary arrangement, a photodynamic therapy may be used,
whereby a predetermined chemical composition may provided to the patient and
the chemical
composition may be selectively activated by a predetermine wavelength, thereby
achieving a
therapeutic reaction. For example, in one exemplary configuration,
illuminating ring 300
may be turned on to achieve the therapeutic reaction. In another exemplary
configuration, a
light source, such as, for example, a fiber optic bundle, may be directed
through outer sheath
102, either directly through outer sheath 102 or through delivery sleeve 800.
[00199] In yet another exemplary configuration, external beam high frequency
ultrasound
or interstitial high frequency ultrasound may also be delivered through outer
sheath and
directly to area of interest 500.
[00200] In yet a further exemplary configuration, as shown in FIGS. 21A-21B,
an
implantable delivery device 900/900' may be provided. Implantable delivery
device
900/900' includes a neck portion 902 that is connected to a body portion
904/904'. Both
neck portion 902 and body portion 904/904' may be constructed of a relatively
soft and
flexible material. Body portion 904/904' defines a reservoir for holding a
therapeutic agent
therein. A proximal end 905 of neck portion 902 is largely closed, with access
to an interior
of implantable delivery device 900/900' being providing by a luer port 906.
More
specifically, therapy agents are introduced into delivery device 900/900'
through luer port
906. A sealing flange 908 may further be provided, that operatively connects
to neck portion
902 to assist in holding implantable delivery device 900/900' in place within
the brain.
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[00201] In the arrangement shown in FIG. 21A, body portion 904 may be provided
with at
least one small opening 910. In one exemplary arrangement, a plurality of
small openings
910 are provided, and such openings may be spaced equi-distance from one
another about the
periphery of body portion 904. Small openings 910 are configured to permit the
therapy
agent that is introduced through luer port 906 to weep out of the reservoir
formed by body
portion 904 at a controlled rate to increase effectiveness. Alternatively,
body portion 900
may be configured as a permeable membrane that permits slow and controlled
passage of
therapy from the reservoir to the brain tissue 1000.
[00202] In an alternative arrangement shown in FIG. 21B, body portion 904' may
be
provided with flexible finger-like projections 912. In one
exemplary configuration,
projections 912 are spaced equi-distance from one another about the periphery
of body
portion 904'. Projections 912 extend outwardly from an outer periphery of body
portion 904'
and may be formed with channels that provide communication between the
reservoir and
small openings 914 configured at distal tips 916 of projections 912. Openings
914 are
configured to permit the therapy agent that is introduced through luer port
906 to weep out of
the reservoir. Projections 914 assist in frictionally retaining delivery
device 900' at a target
site.
[00203] Referring back to process 400, if delivery device 900/900' is
employed, delivery
device 900/900' is inserted at area of interest 500 through outer sheath 102.
Once positioned,
outer sheath 102 is removed, and sealing flange 908 is operatively connected
to neck portion
902 such that luer port 906 is accessible. Sealing flange 908 is configured to
extend over the
periphery of the surgical access opening that was formed through the skull
1002, thereby
providing protection for the exposed brain tissue 1000. The therapeutic agent
may be
supplied to the reservoir formed by body portion 904/904' either before
delivery device
900/900' is positioned at area of interest 500, or after sealing flange 908 is
in place. Sealing
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flange 908, as well as body portion 904/904' and neck portion 902 may be
configured with
flexible material to allow for sealing against the dura and bone of the brain.
[00204] In yet another alternative arrangement involving delivery device
900/900', a
transfer material may be delivered through outer sheath 102, similar to a foam
that is
configured to conform to the cytoreducted area of interest 500. The foam will
allow
continuous contact with the therapy agent that weeps through body portion
904/904' to
provide a controlled dosage of therapy to area of interest 500.
[00205] After surgery and therapy on the target tissue is complete, the
process proceeds to
step 446. In this step, the instruments used for surgery and/or therapy are
removed from
outer sheath 102. As the target tissue is removed, brain tissue will naturally
fill the void
formed by removing area of interest 500 so that healthy brain tissue
underlying the now
removed target tissue is adjacent the end of outer sheath 102. Outer sheath
102 is then gently
removed and the brain tissue will naturally fill and reclaim the space
formerly occupied by
the abnormality and outer cannula 102, aided by the irrigation of area of
interest 500.
Moreover, as the brain tissue reclaims the space formerly occupied by the
abnormality and
outer cannula 102, implanted therapies, such as, for example, bioabsorbable
radiation pellets,
wafers or mesh, will be held in place at area of interest 500 to provide
effective treatment, all
delivered and unencumbered by the limitations normally encountered attempting
to cross the
blood brain barrier. While this process may take several minutes, it is
relatively atraumatic.
Once outer sheath 102 has been removed, the process continues to step 448,
whereby the
dura, skull and scalp are then closed in a known manner and the process ends.
In the
exemplary cases whereby a treatment device may be implanted, full reclaiming
of the space
is delayed due to the implant until implant is explanted or absorbed.
[00206] Because
the location of the area of interest will vary from patient to patient, in one
exemplary arrangement, it is contemplated that surgical access system 100 will
be provided
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as part of a kit. More specifically, it is contemplated that a set of multiple
obturators 104 may
be provided that have different lengths and/or diameters. The set may be
provided in a
container that is configured be sterilized, with obturators 104 secured
therein. It is also
contemplated that a set of manipulation tools 700/700' may also be provided
with the kit, and
that manipulation tools 700/700' may be positioned within the container for
selective
sterilization. Outer sheath 102 may be provided with the kit, in various
lengths and diameters
that correspond to the lengths and diameters of obturators 104 provided in the
kit. However,
in one exemplary arrangement, outer sheaths 104 are provided separately as
single use
devices, in sterilized pouches.
100207] While the above-described system provides the advantage of creating
direct access
to an area of interest, including an area of interest in the subcortical
space, thereby permitting
debulking of the area of interest to reduce the biological load of the
abnormal tissue, as well
as delivery of therapy in-situ (without the encumbrance and limitations
encountered with
systemic therapy delivery), for certain diseases, additional subsequent
therapy may be
warranted for increased therapeutic benefits.
1002081 More specifically, to be able to define an effective subsequent
treatment therapy
cocktail that will be effective on newly evolved strain of cells and tissue or
disease that
"morphs", the abnormal tissue at the area of interest requires imaging to
define the area of
interest, needs to be accessed, requires interrogation (sampling with or
without a
cytoreductive debulking of the area) to determine an appropriate therapeutic
cocktail for the
newly evolved cells and tissue. This process may be required to be repeated at
a specific time
or at a variety of time intervals for the live of the patient to assure the
appropriate
management or cure of the disease.
1002091 In the case of functional diseases of the brain such as a
Alzheimer's, Parkinson's,
epilepsy, bi-polar, depression, etc., the cells and affected tissues may not
change or morph
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after the initial treatment but it may be useful to subsequently, image,
access, interrogate the
tissue (sample or debulk) the same or another area of interest after the
initial delivery of a
therapy to determine the effectiveness of the previous application to
determine the response
of the tissues to the treatment regimen to determine the need for subsequent
treatment
regimens and the nature of the therapeutic treatment required for the
subsequent therapy.
[00210] Referring to FIG. 22, a process flow 1200 illustrating an
additional method of
treatment is disclosed to address a second stage treatment regime. Process
flow 1200 begins
a predetermined time period 1202 after an initial resection and treatment
process flow 400 (as
shown in FIG. 13) has been completed. The need, if any, for process flow 1200
and the
predetermined time period 1202 will depend on the effectiveness of the initial
treatment and
the nature of the disease being treated disease state- morphing, as well as
the form of therapy
that is originally applied. The process then proceeds to step 1204.
[00211] In step 1204, the area of interest 500 is re-imaged to determine
the effects of
therapy on area of interest 500. In other words, step 402 of process 400 is
repeated. Such
imaging includes, but is not limited to, MR! or CT imaging. The process then
proceeds to
step 1206.
[00212] In step 1206, a determination is made as to whether any disease is
visible after
employing the imaging step 1204. For certain diseases, if no visible disease
is detected 1208,
the process 1200 stops. For certain low-grade gliomas, for example, no more
intervention
may be required. For other diseases, i.e., fast growing tumors such as
gliomas, if external
imaging modalities fails to detect any visible disease, based on the patient
history including
prior disease pathology, it may be warranted to employ an in-situ imaging
technique in step
1210. Some examples of such techniques include, but are not limited to
spectroscopy, MR',
ultrasound, florescence. If, after completion of step 1210, no visible sign of
disease are
CA 3010024 2018-06-28
evident, the process stops. However, if after steps 1206 and 1210, the imaging
step reveals
visual evidence of disease, the process proceeds to step 1212.
[00213] In step 1212, many of the steps of the process flow 400 set forth in
FIG. 13 is
repeated. More specifically, steps 406-426 of process flow 400 are repeated to
create access
to area of interest 500. Next the process proceeds to step 1214.
[00214] In step
1214, area of interest 500 is interrogated (via additional cyto-reduction or
just sampled /biopsy), similar to steps 428-434 in FIG. 13. Indeed, after the
initial treatment
process, the disease may have mutated such that the disease may be of a
slightly different
variant of the diseased tissue that was originally treated. As such, use of
the same therapeutic
cocktail in in-situ may no longer be effective. Accordingly, step 1214
involves interrogating
the area of interest 500 to gather and determine the necessary information
regarding the
tissue make up of the area of interest 500. Next, the process proceeds to step
1216.
[00215] In step 1216, tissue from area of interest 500 is analyzed to
determine the
appropriate and effective therapy to treat area of interest 500. In other
words, evaluation of
differentiating cells from area of interest 500 may be utilized to provide the
most effective
treatment for the disease. In some instances, immunotherapy may be utilized,
whereby tissue
samples taken from area of interest 500 are used to determine and subsequently
formulate a
therapy of personalized medicine to the specific disease mutation identified
and analyzed in
step 1216. One exemplary, non-limiting type of such immunotherapy is taught
and disclosed
in co-pending U.S. application serial no. 13/352,069.
Once an appropriate therapy is determined, the
process proceeds to step 1218, whereby the therapy is applied to area of
interest.
[00216] The therapy may be applied in any suitable manner. For example, in
some
instances, it may be necessary to remove the outer sheath to deliver the
therapy, such as that
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taught in steps 438-440 in FIG. 13. In other situations, the outer sheath may
remain in place
and the chosen therapy may be delivered in a manner similar to steps 442-446
in FIG. 13.
(002171 Once therapy has been appropriately delivered, the process then
proceeds to step
1220 whereby the surgical access is closed in a manner similar to that which
has been
previously described above in connection with step 448 in FIG. 13. However, it
is
understood that the process flow 1200 may be repeated as needed until the
patient is deemed
disease free or the disease is managed to a point whereby it is not life
threatening.
1002181 It will be appreciated that the surgical access system and methods
described herein
have broad applications. The foregoing embodiments were chosen and described
in order to
illustrate principles of the methods and apparatuses as well as some practical
applications.
The preceding description enables others skilled in the art to utilize methods
and apparatuses
in various embodiments and with various modifications as are suited to the
particular use
contemplated. In accordance with the provisions of the patent statutes, the
principles and
modes of operation of this disclosure have been explained and illustrated in
exemplary
embodiments.
100219)
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