Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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SURGICAL DEFLECTOR TOOL
FIELD OF THE INVENTION
The present invention relates to the field of surgical apparatus and
more specifically, to a surgical apparatus for deflecting a tissue retraction
means.
BACKGROUND OF THE INVENTION
Cardiac surgery generally requires an incision through the patient's
skin, underlying muscle and tissue, and often a retraction of the patient's
ribcage in
order to access the patient's underlying coronary organs. Traditional cardiac
surgery
has been commonly performed through a midline sternotomy incision, where the
patient's sternum is incised and the ribcage retracted to obtain access to the
patient's
heart and major blood vessels. More recently, in minimally invasive
procedures,
smaller parasternal incisions (mini-sternotomy) or intercostal thoracotomy
approaches have also been employed. In thoracotomy approaches, two adjacent
ribs
are spread apart at times even removing a length of rib to improve access into
the
patient's thorax and to the patient's heart. In these approaches, a chest
retractor is
used to spread apart the patient's skin and thoracic bone structure to
maintain an
incised opening, or surgical window, onto the underlying cardiac tissue.
Chest retractors exist in many sizes and shapes and have been present
since the dawn of cardiac surgery. Most known chest retractors have an
elongate
rack bar and two retracting arms, namely a fixed retracting arm and a movable
retracting arm. Both arms typically extend in a direction normal to the rack
bar.
The movable arm can be displaced along the rack bar, and relative to the fixed
arm,
by using a crank to activate a pinion mechanism which engages teeth on the
rack bar.
Two blades are generally provided, usually disposed below the retractor arm
and
extending into the surgical incision, to interface with the patient's skin or
thoracic
bone structure. These two blades apply the retraction that creates the
surgical
window by the relative movement, and an ensuing spacing apart, of the two
retractor
arms. In addition, chest retractors may also serve as a substantially stable
surgical
platform for engaging surgical apparatus used during the course of the
surgical
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intervention. Through this engagement with the chest retractor, the surgical
apparatus may be set in a substantially stable position or orientation
relative to
cardiac tissue implicated in the surgical intervention. Cardiac tissue
includes
pericardium, epicardium, myocardium, endocardium, tissue of the septal wall,
aorta
tissue, vena cava tissue, cardiac valves, heart muscle, the coronary arteries
and
veins, the pleurae, the thymus, and other like anatomical tissue.
One type of cardiac surgery known as coronary artery bypass graft
(CABG) surgery has been traditionally performed with the support of a cardio-
pulmonary machine, whereby the patient's blood is oxygenated outside the body
through extracorporeal circulation (ECC). This allows the surgeon to perform
surgical procedures on a perfectly still heart while the patient's life
support is
maintained by cardio-pulmonary assistance. During traditional CABG surgery,
the
surgeon or assistant may manually or otherwise manipulate the arrested heart
into a
position and orientation that yields the best access to a target artery
requiring a
bypass graft. The great majority of CABG surgeries (approximately 70%) are
triple
vessel bypass surgeries; that is, at least one bypass graft is performed on
each of the
anterior, inferior and posterior artery beds of the patient's heart.
Recently, in an aim to render CABG surgery less invasive to the
patient, beating heart CABG surgery is being developed whereby ECC, one of the
most invasive aspects of cardiac surgery, is eliminated and coronary artery
revascularization is performed directly on the beating heart. One of the
challenges
in performing beating heart CABG surgery lies in positioning and orienting the
beating heart in order to obtain access to the inferior and posterior artery
beds, while
aiming to minimize physiologically undesirable effects such as hemodynamic
instability, arrhythmia, or a precipitous drop in arterial pressure, any of
which may
occur as a result of such beating heart manipulations. Furthermore, a surgical
device
placed directly in contact with the beating heart which enables manipulations
of the
beating heart or which restrains its movement or positioning may impose loads
and
constraints on the beating heart. This may impede the normal beating function
of the
heart and induce the onset of the physiologically undesirable effects
described
above. In traditional CABG surgery, the heart is arrested and therefore heart
manipulations are well tolerated.
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During CABG surgery or beating heart CABG surgery, the
pericardium, namely a substantially thin membranous tissue forming a sac in
which
the heart and the commencement of the major blood vessels connecting with the
heart are contained, is generally incised and unraveled to expose at least a
portion of
the heart surface which is to receive the bypass graft. The pericardium
tissue, unlike
the heart, is not beating and it may be separated from the heart surface
except in
certain locations where it is anatomically attached to the heart. Thus, it is
surgically
possible in CABG surgery, to position and orient the heart through retraction
of the
pericardium tissue to obtain access to the inferior and posterior coronary
artery beds.
In beating heart CABG, heart manipulations achieved through retraction of the
pericardium tissue tend to reduce the likelihood of inducing trauma to the
beating
heart, tend to not distort the heart's chambers that may compromise blood
ejection
capacity, and tend to minimize the physiologically undesirable effects
mentioned
above, since direct contact with the beating heart is avoided. One such
beating heart
manipulation consists of "verticalizing" the heart in order to gain access to
the
posterior artery bed. In this maneuver, the pericardium is engaged close to
the base
of the heart with one or more tissue retraction means (preferably 1 to 1.5
inches
away from the pericardial reflection) and the apex of the heart is rotated
outward
from the retracted chest cavity through the tensile loads applied to the
engaged
pericardium. The longitudinal axis of the beating heart thereby assumes
substantially vertical orientation (with the patient lying in a supine
position on the
operating table).
Pericardial retraction may be achieved through a variety of tissue
retraction means. Sutures such as traction or stay sutures have been generally
employed in cardiac surgery and are one such means of achieving pericardial
traction. Sutures generally consist of a tissue piercing member such as a
relatively
sharp needle and a length of wire-like filament such as a suture line
integrally
attached to the blunt end of said needle. In the application of pericardial
traction
sutures, the needle pierces the pericardium tissue, a certain length of suture
line is
then threaded through the pierced pericardium tissue, and the resultant two
ends of
the suture line (i.e. the length between the pierced tissue and the free end
of the
suture line and the length between the pierced tissue and the needle-bearing
end of
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the suture line) are then simultaneously pulled to impart the retraction load
on the
pericardium tissue and consequently displace the beating heart which is
anatomically
attached to said pericardium tissue.
In order to "verticalize" a beating with pericardial traction sutures, a
number of such sutures must be inserted through and engaged with the
pericardium
tissue preferably along its pericardial reflection in order to get the desired
lifting of
the apex and consequently a good exposure to the posterior coronary bed. For
example, one traction suture may be placed between the superior and inferior
pulmonary vein, a second one below the inferior pulmonary vein, a third one
midway
between the apex of the heart and the inferior pulmonary vein, and a fourth
one
towards the diaphragmatic face near the inferior vena cava. Pericardium
retraction
loads are subsequently applied to each of these traction sutures
independently. The
resultant lengths of suture line must then be secured to a stable surgical
platform
such as a chest retractor to maintain the desired retraction load on the
pericardium
tissue. Standard surgical clamps may be used to secure the two resultant
lengths of
suture line relative to the chest retractor through a variety of methods.
Alternatively,
a tissue retraction means consisting of a suture line with an associated
anchoring
means may also be used to apply and maintain the pericardial traction loads,
and also
the resultant heart position and orientation relative to the chest retractor.
Such types
of tissue retraction means are described more fully in co-pending Canadian
patent
application Serial No. 2,242,295 filed on August 10, 1998 in the names of
Paolitto et
al. and entitled "Surgical Instruments for Tissue Retraction", for which a
corresponding PCT application Serial No. PCT/CA99/ 00740 has been filed on
August 10, 1999 in the names of Paolitto et al. and entitled "Surgical Suture
and
Associated Anchoring Mechanism for Tissue Retraction". In both these methods
of
applying pericardial retraction, the engagement of the pericardium tissue is
achieved
through piercing of said pericardium tissue.
Alternatively, another type of tissue retraction means may consist of
engaging the pericardium tissue with a negative pressure suction force. The
suction
force may be applied through a flexible suction port. A retraction load may be
imposed by pulling on the flexible tubular conduits which communicate the
negative
pressure to the said suction port from a negative pressure source. The said
retraction
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load is maintained by securing a part of this negative pressure apparatus,
most
commonly the flexible tubular conduit, relative to a stable surgical platform
such as
a chest retractor. Such types of negative pressure tissue retraction means are
described more fully in co-pending Canadian patent application Serial No.
2,242,766
filed on August 17, 1998 in the names of Paolitto et al. and entitled
"Pericardium
Retraction Device for Positioning a Beating Heart", for which a corresponding
PCT
application Serial No. PCT/CA99/00757 has been filed on August 17, 1999 in the
names of Paolitto et al. and entitled "Pericardium Retraction Device for
Positioning
a Beating Heart." In yet other types of tissue retraction means, the
pericardium
tissue may be engaged by tissue-grasping or tissue-clamping members which
grasp
or clamp at least a portion of said pericardium tissue.
To maintain the position and orientation of the beating heart achieved
through pericardial traction, the tissue retraction means is secured at its
anchoring
location to a suitable substantially stable surgical platform such as a chest
retractor.
As will be illustrated and described more fully below, once the pericardial
retraction
load is secured, a vector may be defined originating from the point of
engagement of
the tissue retraction means with the pericardium tissue and generally directed
along
the tissue retraction means towards a point of anchoring on a suitable
surgical
platform.
Often times within a retracted chest cavity, the projected distance
between a deployed tissue retraction means and the heart surface may be small
and
restrictive for certain types of surgical interventions. This is more often
the case
when the patient's ribcage is retracted a minimum amount, when the patient's
heart
is enlarged due to disease, or when the pericardium tissue is engaged with a
tissue
retraction means in a deep location close to the pericardial reflection. For
instance,
in a beating heart revascularization of a posterior coronary artery, with the
patient's
heart verticalized through pericardial retraction, the projected distance
between the
pericardial traction sutures and the posterior heart surface may be small or
restrictive
that it may hinder not only the deployment of coronary stabilizers that
immobilize
the portion of beating heart around the posterior target artery, but may also
compromise the quality of the posterior artery bypass graft.
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In another type of cardiac surgery such as mural valve surgery,
surgical access to the diseased mitral valve is mostly achieved through a
surgical
incision of the left atrium. To attempt to achieve optimal exposure, the heart
is
elevated out of the chest and rotated, allowing the apex to drop posteriorly
while
elevating the right side of the heart. This maneuver tends to bring the
posterior
mitral valve leaflet toward the right side of the patient in a plane which
tends to face
the surgeon, often permitting better visualization of the mitral valve and
subvalvular
structures. Following the median sternotomy, the pericardium is opened
slightly to
the right of the midline and the right side of the pericardium is sutured
under tension
to the chest wall or secured under tension to a point on a stable surgical
platform in
the nature of a chest retractor. This helps to provide the elevation of the
right side of
the heart. The pericardial edges on the left side of the incision are usually
not
suspended. After bicaval cannulation, the superior vena cava is usually
mobilized by
incising the pericardium above it. A tourniquet is often placed on the
inferior vena
cava and traction is applied in a general direction toward the patient's feet.
This
tourniquet may also be secured to the chest retractor. This procedure further
helps to
elevate the right side of the patient's heart. The left atrium is incised
parallel to the
intra-atrial groove. This incision is usually extended below the superior vena
cava
and a considerable distance below the inferior vena cava.
At times during cardiac surgery, the patient's heart surface or cardiac
tissue is constrained by, or in close vicinity to, the patient's pleura and
lungs.
Access to the surgical intervention site on the patient's heart surface may
have to be
obtained by assistant-hand-held retractors deployed to displace the pleura and
lungs.
It is therefore an object of the invention to provide a surgical deflector
tool attempting to alleviate or eliminate the above-mentioned drawbacks.
It is a further object of the invention to provide a surgical deflector
tool which tends to improve surgical access and visibility to a given body
organ or
body tissue where a surgical intervention is intended to take place, such as a
coronary organ, cardiac tissue and the like.
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BRIEF SUMMARY OF THE INVENTION
The invention provides a surgical deflector tool comprising a
deflection member adapted for connection to a surgical platform, said
deflection
member, in use, being adapted to deflect at least a portion of a tissue
retraction
means when said tissue retraction means is simultaneously engaged with a body
tissue and with said surgical platform.
For instance, the tissue retraction means may be deflected from an
initial, non-deflected position prior to its engagement with said deflection
member,
to a second deflected position after engagement with said deflection member.
When
said body tissue is anatomically attached to a body organ, the deflection of
the tissue
retraction means relative to its initial position with respect to said organ,
and prior to
its engagement with said deflection member, is advantageously in a direction
substantially away from the surface of said body organ.
During a cardiac surgery, such a surgical deflector tool advantageously
provides a deflection member that is adapted to displace at least a portion of
a
deployed tissue retraction means engaged with the pericardium tissue
anatomically
attached to the heart, away from the portion of the heart surface that is
situated in the
general vicinity of where a surgical intervention is intended to take place.
Consequently, the surgical access and surgeon's vision tends to be improved at
the
site of the intended surgical intervention.
During cardiac surgery, the pericardium tissue is generally incised
along the anterior surface of the heart and generally along the heart's major
axis. In
certain instances, the tissue retraction means engages the pericardium tissue
at a
location close to the pericardial incision (and in the vicinity of the
anchoring point
of tissue retraction means to the chest retractor). As such, a deployed
surgical
deflector tool may be in contact with and deflect a portion of the pericardium
tissue
that is engaged with said tissue retraction means.
As described above, heart verticalization may be achieved through
beating heart manipulations that are substantially well tolerated by the
patient. In
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certain instances, such manipulations performed in conjunction with the
deployment
of a surgical deflector tool, tends to improve the likelihood of achieving
complete
coronary artery revascularization on the beating heart. Complete
revascularization is
considered by most to be the gold standard in revascularization surgery, which
till
date has been mostly achieved through traditional CABG.
In another example of cardiac surgery affecting the mitral valve, the
surgical deflector tool may be used to displace or deflect at least a portion
of a
pericardium retraction suture used to position or orient the patient's heart
within the
retracted chest cavity. At times, the surgical deflector tool may be in
contact with
and displace or deflect a portion of the retracted pericardium tissue which,
at some
location is engaged with at least one pericardium retraction suture. Said
deflections
or displacements are in a direction away from the heart's surface tissue
thereby
tending to improve surgical access to the diseased mitral valve.
In another example of cardiac surgery, the surgical deflector tool of the
invention is advantageously adapted to displace at least a portion of the
pleura and
lungs, or other like anatomic tissue, in a direction generally away from the
patient's
heart surface where a surgical intervention is intended to take place. At
times, the
pleura may be engaged with a tissue retraction means which is simultaneously
secured to a chest retractor. As such, the surgical deflector tool may also be
deployed to displace a lung through the deflection of a tissue retraction
means that is
in turn engaged with said pleura tissue. Alternatively, the surgical deflector
tool
may also be deployed to displace a lung through the contact with and
deflection of
the said pleura which is engaged at some location with a tissue retraction
means, and
said tissue retracting means is simultaneously anchored to a chest retractor.
Similar
advantages with other types of surgery, either cardiac or non-cardiac, may
also be
provided with the surgical deflector tool of the present invention.
In cardiac surgeries where the heart has been positioned or oriented
through retraction of the pericardium tissue anatomically attached to said
heart, the
surgical deflector tool tends to improve surgical access to a target portion
of the said
heart where a surgical intervention is intended to take place, by deflecting
at least a
portion of the pericardium tissue which is engaged at some location with a
tissue
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retraction means, or at least a portion of the tissue retraction means engaged
with
pericardium tissue, away from said target portion of said heart. As such, in
CABG
surgeries, the surgical deflector tool tends to improve the efficacy and
quality of
bypass grafts performed on an inferior or posterior coronary artery of a
patient's
heart by tending to enhance the surgeon's visibility and surgical access to
the target
artery. The deflector advantageously maintains at least a portion of the
pericardium
tissue which is engaged at some location with a tissue retraction means, or at
least a
portion of a tissue retraction means engaged with the pericardium tissue, away
from
the target portion of the patient's heart where the surgical intervention will
take
place.
In the various examples, the tissue retraction means may be a surgical
suture, a negative pressure suction line, a grasping member, a clamping
member, or
other like tissue retraction member. The surgical platform is preferably a
chest
retractor such as a sternum retractor.
Preferably, the surgical deflector tool further comprises an elongated
connection member cooperating with said deflection member and adapted for
connection to said surgical platform.
The connection member enables the deflection member to be placed in
a given desired position or orientation with respect to the surgical platform.
In a
variant, the position and orientation may be selected from among a plurality
of
possibilities.
The connection member advantageously comprises a first end portion
connected to said deflection portion, and a second end portion, adapted for
connection to said surgical platform.
This first example of connection member tends to be relatively simple,
reliable and cost effective.
The connection member may be telescopic.
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This example provides a connection member that is collapsible or
extendible to a variable length, before or during a surgical intervention. As
such, this
example tends to offer compact deployment, flexibility in the surgical set-up,
and
ease of in-process re-adjustments, if required.
In another example, the connection member is flexible and lockable so
that its configuration may be easily modified to enable requisite placement of
the
deflection member in various positions and/or orientations within the surgical
workspace at which point the desired configuration may be locked during a
surgical
intervention.
The connection member may slidingly engage with said surgical
platform. The connection member may slidingly engage with said deflection
member.
These two examples provide variability in setting the position of the
deflection member
relative to the surgical platform.
The said deflection member may be pivotingly connected to said
connection member.
This type of joint between the deflection member and connection
member advantageously provides the surgeon with the ability to place the
deflection
member in an optimum orientation with respect to the surgical platform given a
specific patient anatomy. In a variant, the orientation of deflection member
may be
selected from among a plurality of possibilities.
The surgical deflector tool of the invention preferably comprises an
adjustment mechanism adapted to set said deflector member in a plurality of
locations and/or orientations (angular settings) with respect to said surgical
platform.
The adjustment mechanism enables the surgeon or assistant to easily
and quickly position or orient the deflection member at the beginning of a
surgical
intervention and /or at any time during or after such intervention. This
allows a
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surgeon to easily customize a surgical set-up and/or modify said set-up during
the
course of a surgery. Moreover, this allows the surgeon to easily vary the
amount of
deflection imposed by the surgical deflector tool on the engaged tissue
retraction
means during the course of a surgery without having to disengage deflection
means
from said surgical platform and/or without having to disengage tissue
retraction
means from said body tissue.
The connection member advantageously comprises a securing
mechanism, capable of being fixed in a plurality of locations to said surgical
platform.
The securing mechanism is advantageously adapted for sliding engagement
with said surgical platform.
In various examples, the connection member is flexible and /or
substantially arcuate. It is advantageously adapted to be slidingly engaged
with said
surgical platform. It is advantageously pivotingly connectable to said
surgical
platform.
Depending on the type of surgery to be performed, the patient's
specific anatomy, the surgeon's distinct work preferences, and other related
parameters, the ability to place the connection member in as many positions,
orientations, or locations relative to the surgical platform offers advantages
in being
able to optimize the surgical approach during a surgical intervention.
In a preferred example, the deflection member is substantially
elongated. An elongated profile enables the simultaneous deflection of a
plurality of
tissue retraction means.
In another example, the surgical deflector tool comprises two securing
mechanisms, said deflection member comprising a deflection member spanning at
least the distance between said two securing mechanisms, said deflection
member
rigidly engaged to at least one said securing mechanism. The deflection member
may
be pivotingly engaged to one securing mechanism and slidingly engaged to the
other
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securing mechanism, or it may also be rotatingly engaged with both securing
mechanisms, said deflection member capable of being fixed in a plurality of
angular
orientations relative to said securing mechanisms by action of said adjustment
mechanism.
In a further example, the surgical deflector tool comprises a plurality
of securing mechanisms each having a flexible portion, said deflection member
comprising a deflection member, said deflection member spanning at least the
distance between each of the securing mechanisms in the said plurality, said
deflection member rigidly engaged to at least one securing mechanism and
slidingly
engaged to the remainder of securing mechanisms in the plurality, said
deflection
member capable of being fixed in a plurality of lengths spanning between any
two
adjacent securing mechanisms by action of said adjustment mechanism.
The invention also provides a surgical deflector tool comprising a
deflection member and a securing mechanism, for deflecting at least a portion
of a
tissue retraction means, said tissue retraction means simultaneously engaged
with a
body tissue anatomically attached to a body organ and with a substantially
stable
surgical platform, said securing mechanism slidingly engaged with said
surgical
platform, said securing mechanism capable of being fixed in a plurality of
locations
to said surgical platform, said deflection member engaged with said tissue
retraction
means, said deflection member serving to deflect at least a portion of said
tissue
retraction means in a direction substantially away from the surface of said
organ
relative to its initial position with respect to said organ prior to
engagement of said
deflection member with said tissue retraction means.
In a variant, the surgical deflector tool further comprises an adjustment
mechanism, said deflection member slidingly engaged with said securing
mechanism, said deflection member capable of being fixed in a plurality of
locations
to said securing mechanism by action of said adjustment mechanism.
The invention also provides a surgical deflector tool comprising a
deflection member and two securing mechanisms, for deflecting at least a
portion of
a tissue retraction means, said tissue retraction means simultaneously engaged
with a
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body tissue anatomically attached to a body organ and with a substantially
stable
surgical platform, said securing mechanisms slidingly engaged with said
surgical
platform, said securing mechanisms capable of being fixed in a plurality of
locations
to said surgical platform, said deflection member engaged with said tissue
retraction
means, said deflection member serving to deflect at least a portion of said
tissue
retraction means in a direction substantially away from the surface of said
organ
relative to its initial position with respect to said organ prior to
engagement of said
deflection member with said tissue retraction means, said deflection member
spanning at least the distance between said two securing mechanisms, said
deflection
member rigidly engaged to at least one said securing mechanism.
The deflection member may be pivotingly engaged to one securing
mechanism and slidingly engaged to the other securing mechanism.
The tool preferably further comprises an adjustment mechanism, said
deflection member rotatingly engaged with said securing mechanism, said
deflection
member capable of being fixed in a plurality of angular orientations relative
to said
securing mechanism by action of said adjustment mechanism.
The invention also provides a surgical deflector tool comprising a
deflection member, an adjustment mechanism and two securing mechanisms, for
deflecting at least a portion of a tissue retraction means, said tissue
retraction means
simultaneously engaged with a body tissue anatomically attached to a body
organ
and with a substantially stable surgical platform, said securing mechanisms
slidingly
engaged with said surgical platform, said securing mechanisms capable of being
fixed in a plurality of locations to said surgical platform, said deflection
member
engaged with said tissue retraction means, said deflection member serving to
deflect
at least a portion of said tissue retraction means in a direction
substantially away
from the surface of said organ relative to its initial position with respect
to said
organ prior to engagement of said deflection member with said tissue
retraction
means, said deflection member spanning at least the distance between said two
securing mechanisms, said deflection member rotatingly engaged with both
securing
mechanisms, said deflection member capable of being fixed in a plurality of
angular
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orientations relative to said securing mechanisms by action of said adjustment
mechanism.
The invention further provides a surgical deflector tool comprising a
deflection member, an adjustment mechanism and a plurality of securing
mechanisms, for deflecting at least a portion of a tissue retraction means,
said tissue
retraction means simultaneously engaged with a body tissue anatomically
attached to
a body organ and with a substantially stable surgical platform, said securing
mechanisms slidingly engaged with said surgical platform, said securing
mechanisms
capable of being fixed in a plurality of locations to said surgical platform,
said
securing mechanism having a flexible portion, said deflection member engaged
with
said tissue retraction means, said deflector serving to deflect at least a
portion of
said tissue retraction means in a direction substantially away from the
surface of said
organ relative to its initial position with respect to said organ prior to
engagement of
said deflection member with said tissue retraction means, said deflection
member
spanning at least the distance between each of the securing mechanisms in the
said
plurality, said deflection member rigidly engaged to at least one securing
mechanism
and slidingly engaged to the remainder of securing mechanisms in the
plurality, said
deflection member capable of being fixed in a plurality of lengths spanning
between
any two adjacent securing mechanisms by action of said adjustment mechanism.
These and other objects of the present invention will become apparent
from the description of the present invention and its preferred embodiments
which
follows.
BRIEF DESCRIPTION OF THE DRAWINGS
For better understanding of the present invention and to show more
clearly how it may be carried into effect, reference will now be made by way
of
illustration and not of limitation to the accompanying drawings, which show an
apparatus according to the preferred embodiments of the present invention, and
in
which:
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Figure 1 is a perspective view illustrating a surgical deflector tool and
a surgical apparatus with which the said surgical deflector tool may be used,
according to a first embodiment of the present invention;
S Figure 2 is an enlarged perspective view of the surgical deflector tool
illustrated in Figure 1, with the verticalized beating heart removed for
clarity;
Figure 3 is an exploded view of the surgical deflector tool illustrated in
Figure 1;
Figure 4 is a perspective view illustrating a surgical deflector tool and
a surgical apparatus with which the said surgical deflector tool may be used,
according to a second embodiment of the present invention;
Figure 5 is an enlarged top view of the surgical deflector tool
illustrated in Figure 4;
Figure 6A is a section view through the surgical deflector tool
illustrated in Figure 5, illustrating said deflector tool in its non-deployed
state;
Figure 6B is a section view through the surgical deflector tool
illustrated in Figure 5, illustrating said deflector tool in its deployed
state;
Figure 7 is a top view illustrating a surgical deflector tool and a
surgical apparatus with which the said surgical deflector tool may be used,
according
to a third embodiment of the present invention;
Figure 8A is a section view through the surgical deflector tool
illustrated in Figure 7, illustrating said deflector tool in its non-deployed
state;
Figure 8B is a section view through the surgical deflector tool
illustrated in Figure 7, illustrating said deflector tool in its deployed
state;
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Figure 9A is a top view illustrating a surgical deflector tool and a
surgical apparatus with which the said surgical deflector tool may be used,
according
to a fourth embodiment of the present invention;
Figure 9B is a section view through the surgical deflector tool
illustrated in Figure 9A, illustrating a pivot-type support frame of said
surgical
deflector tool;
Figure 9C is a section view through the surgical deflector tool
illustrated in Figure 9A, illustrating a yoke-type support frame of said
surgical
deflector tool;
Figure 10A is a top view illustrating a surgical deflector tool and a
surgical apparatus with which the said surgical deflector tool may be used,
according
to a fifth embodiment of the present invention;
Figure lOB is a side elevational view through the surgical deflector
tool illustrated in Figure 10A, illustrating a louver-type deflector of said
surgical
deflector tool;
Figure lOC is a section view through the surgical deflector tool
illustrated in Figure IOB, illustrating an adjustment mechanism of said
surgical
deflector tool;
Figure 1 1A is a top view illustrating a surgical deflector tool and a
surgical apparatus with which the said surgical deflector tool may be used,
according
to a sixth embodiment of the present invention;
Figure 11B is a section view through the surgical deflector tool
illustrated in Figure 11A, illustrating a solid-flange support frame of said
surgical
deflector tool;
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Figures 11C and 11D are section views through the surgical deflector
tool illustrated in Figure 11A, illustrating sliding-flange support frames of
said
surgical deflector tool;
Figure 1 1E is a section view through the surgical deflector tool
illustrated in Figure 11A, illustrating a support frame with integral housing
for
adjustment mechanism of said surgical deflector tool;
Figure 11F is a section view through the surgical deflector tool
illustrated in Figure 11A, illustrating a housing and adjustment mechanism of
said
surgical deflector tool;
Figure 12A is a top view illustrating a variant securing mechanism in
the nature of a T-nut, according to the present invention;
Figure 12B is a section view through the variant securing mechanism
illustrated in Figure 12A;
Figure 13A is a top view illustrating a variant securing mechanism in
the nature of a modified T-bolt, according to the present invention;
Figure 13B is a section view through the variant securing mechanism
illustrated in Figure 13A;
Figure 14A is a side elevational view illustrating a variant securing
mechanism in the nature of a radially-engaging cam, according to the present
invention;
Figure 14B is a section view through the variant securing mechanism
illustrated in Figure 14A;
Figure 1 SA is a side elevational view illustrating a variant securing
mechanism in the nature of a grommet-type expansion joint, according to the
present
invention;
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Figure 15B is a section view through the variant securing mechanism
illustrated in Figure 15A;
Figure 16 is a side elevational view illustrating a variant securing
mechanism in the nature of a C-shape flange, according to the present
invention;
Figure 17 is a side elevational view illustrating a variant securing
mechanism in the nature of a retaining clip, according to the present
invention;
Figure 18A is a perspective view illustrating a surgical deflector tool
and a surgical apparatus with which the said surgical deflector tool may be
used,
according to a seventh embodiment of the present invention;
Figure 18B is a section view through the surgical deflector tool
illustrated in Figure 18A, illustrating said deflector tool in its deployed
state;
Figure 18C is an exploded view of the surgical deflector tool illustrated
in Figure 18A;
Figure 19 is a perspective view illustrating a surgical deflector tool and
a surgical apparatus with which the said surgical deflector tool may be used,
according to an eight embodiment of the present invention;
Figure 20 is a perspective view illustrating a surgical deflector
arrangement and a surgical apparatus with which the said surgical deflector
arrangement may be used, according to an ninth embodiment of the present
invention;
Figure 21 is a perspective view illustrating a variant mechanical joint
between deflection member and connection member in the nature of a pivoting
joint,
according to the present invention;
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Figure 22 is a perspective view illustrating a variant mechanical joint
between deflection member and connection member in the nature of a sliding
joint,
according to the present invention;
Figure 23 is a perspective view illustrating a variant connection
member in the nature of a collapsible and extendable telescopic arm, according
to
the present invention;
Figure 24 is a perspective view illustrating a variant connection
member in the nature of a flexible, lockable arm, according to the present
invention;
Figure 25 is a perspective view illustrating a surgical deflector tool and
a surgical apparatus with which the said surgical deflector tool may be used,
according to a thirteenth embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The features and principles of this invention can be applied, in whole
or in part, to other types of cardiac surgery or other surgery whereby a body
organ is
positioned or oriented through the retraction of a body tissue anatomically
attached
to said body organ, and the setting of a desired position or orientation of
said body
organ is achieved through the securing of the retraction load relative to a
substantially stable surgical platform. The embodiments of the present
invention
that follow will however be described and illustrated in the context of
cardiac
surgery, and more specifically, CABG surgery.
In part, the embodiments of this invention may be advantageously
applied, if desired, to the chest retractor described in copending Canadian
patent
application Serial No. 2,216,893 filed on September 30, 1997 in the names of
Cartier
and Paolitto and entitled "Sternum Retractor for Performing Bypass Surgery on
the
Beating Heart" and in copending Canadian patent application Serial No.
2,237,877
filed on June 26, 1998 in the names of Paolitto et al. and entitled "Chest
Retractor
for Performing Cardiac Surgery", for which a corresponding PCT application
Serial
No. PCT/CA99/00593 has been filed on June 25, 1999 in the names of Paolitto et
al.
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and entitled "Surgical Retractor Having Low-Friction Actuating Means and
Contoured Blade Arms", the contents of which are incorporated herein by
reference.
Alternatively, the embodiments of the invention may also be applied to other
types
of chest retractors capable of securing a surgical deflector tool according to
the
present invention in a substantially stable orientation and position relative
to the
chest retractor. Alternatively, the chest retractor may be replaced by other
substantially stable surgical platforms that may be engaged with a surgical
deflector
tool according to the present invention. Such surgical platforms would
include: a
surgical table, a surgical bridge or truss or truss member attached to a
surgical table
and spanning the patient or set adjacent to the patient, or other like
platforms.
In part, the embodiments of this invention may be advantageously
applied, if desired, to the tissue retractor described in above referenced
Canadian
patent application Serial No. 2,242,295 for which a corresponding PCT
application
Serial No. PCT/CA99/ 00740 has been filed, the contents of which are
incorporated
herein by reference.
By way of a general overview and with reference to Figure l, a surgical
apparatus with which the invention may be used is comprised of three main
components, a surgical deflector tool 100, a tissue retraction means in the
nature of a
surgical suture 10, and a chest retractor such as sternum retractor 5. The
sternum
retractor 5 is illustrated in its deployed state, thereby creating and
maintaining a
surgical window that provides the surgeon with access to the patient's cardiac
tissue.
During the course of a cardiac surgery, a surgeon needs to perform certain
tasks
within a surgical workspace. This surgical workspace is defined by an area
that
contains the perimeter of a deployed sternum retractor S and a buffer zone
therebeyond, and said area extending below to the depth of the patient's
thorax, and
above to the height above the retracted chest cavity in which the surgical
apparatus
comprising the surgical deflector tool is contained and manipulated.
The sternum retractor 5 includes four major parts: (i) an elongated rack
bar 52, (ii) a first retractor spreader arm 3 being preferably fixed to the
rack bar 52,
(iii) a second retractor spreader arm 4 being preferably movable with respect
to the
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rack bar 52, and (iv) an crank handle 6 for effecting movement of the
retractor
spreader arm 4 relative to retractor spreader arm 3.
Retractor spreader arms 3 and 4 extend in a direction substantially
transversely with regard to the rack bar 52, generally in the same direction
therefrom
and in a parallel orientation with respect to one another. The movable arm 4
can be
displaced along the rack bar 52, and relative to the other arm 3, preferably
through
the rotation of the crank handle 6 activated by the surgeon. The crank handle
6 is
operatively connected to the rack bar 52 and to the other spreader arm 4, and
is
translatable along the length of the rack bar 52. This is preferably achieved
by the
engagement of a pinion mechanism (not shown) of crank handle 6 with the rack
teeth
on rack bar 52. Two retractor blades 7 and 8 are respectively provided with
the
retractor spreader arms 3 and 4, preferably disposed below the rack bar 52
when the
sternum retractor 2 is deployed on a patient. The retractor blades 7 and 8
engage
with and serve to retract a portion of the patient's incised skin, the two
halves of the
patient's incised sternum and the patient's ribcage thereby exposing the
cardiac
tissue to be operated on through the resultant surgical window. When viewing
the
resultant surgical window from above the patient, the retractor arms 3 and 4
of the
deployed sternum retractor 5 each have a generally arcuate orientation.
The sternum retractor 5 advantageously comprises arcuate rails 70 and
80 along the top of arcuate retractor spreader arms 3 and 4, respectively. The
rails
70 and 80 configure an inverted T-slot arcuate passage 71 and 81,
respectively,
preferably centrally located within said rails, and preferably extending
throughout
the entire arcuate length of said rails. A similar linear longitudinal rail
50, may also
be configured along the top of rack bar 52. Longitudinal rail 50 is also
configured
with an inverted T-slot longitudinal passage 51, preferably extending
throughout its
entire longitudinal length. These said rails form a mounting perimeter that
can
advantageously serve to engage a surgical deflector tool 100 in a variety of
substantially stable positions and orientations within a surgical workspace.
As well,
these rails can also be utilized to engage other surgical apparatus, that may
need to
be secured along the perimeter of the sternum retractor S during cardiac
surgery. For
instance, these rails may advantageously serve to engage a positioning and
articulation mechanism utilized to place a variety of heart stabilizers during
beating
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heart bypass surgery, for instance, as described in previously mentioned
Canadian
application Serial No. 2,216,893. Alternatively, the positioning and
articulation
mechanism may also be utilized to set a cardiac tissue contacting member used
in
cardiac surgery, such as a valve tissue retractor for example. As well, these
rails can
also be utilized to engage other surgical apparatus, that may need to be
secured along
the perimeter of the sternum retractor 5 during cardiac surgery.
A plurality of slit-like channels 72 and 82 are configured along the
arcuate arms 3 and 4 and cut through arcuate rails 70 and 80, respectively.
Figure 1
illustrates a plurality of such slit-like channels 72 on the retractor
spreader arm 3 and
a plurality of such slit-like channels 82 on the retractor spreader arm 4. The
slit-like
channels 72 and 82 extend downwards from the top of the rails 70 and 80 to a
depth
preferably below the entire depth of the inverted T-slot arcuate passages 71
and 81,
preferably by an amount equivalent to the width of said slit-like channel.
Similar
slit-like channels were introduced in above-mentioned Canadian patent
application
Serial No. 2,242,295 in order to provide passages for the placement of sutures
serving to retract body tissue, for example pericardium tissue. These said
slit-like
channels are configured so that a suture line or other like wire-like filament
will not
restrict or otherwise hinder the functionality of a surgical deflector tool or
a
positioning and articulation mechanism when such devices becomes engaged in
said
passages 71 and 81 of said rails 70 and 80, provided the suture line or other
wire-like
filament is placed in the deepest position within said slit-like channel.
Figure 1 illustrates an example of one possible surgical set-up whereby
the patient's heart is verticalized through pericardial retraction, prior to
possibly
performing beating heart bypass graft surgery on a posterior or inferior
coronary
artery. Coronary stabilizers that may be used to immobilize a portion of the
beating
heart surface around the target artery requiring grafting are not shown. In
this
example, four tissue retraction means in the nature of a surgical suture 10
are used to
apply pericardial traction to the patient's incised pericardium tissue
(labelled as
PCT). Once the desired pericardial retraction load is applied to each surgical
suture
10, both ends of the surgical suture are inserted into one of slit-like
channels 82 (or
72 in other surgical set-ups), and the desired retraction load is maintained
by
securing the two ends of the surgical suture 10 relative to sternum retractor
5 with
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surgical clamp 9. Alternatively, both ends of a surgical suture 10 may also be
placed
over rack bar 52 and in between two rack bar teeth (not shown), and secured
relative
to said rack bar by a surgical clamp 9. As such, the longitudinal axis of the
heart
assumes a substantially vertical orientation with the apex (labelled as APX)
of the
verticalized beating heart (labelled as VBH) resting substantially proud above
the
plane formed through the top of deployed sternum retractor rails 70 and 80. In
this
example, the patient is placed in a substantially horizontal supine position
on a
surgical table. In this example, rack bar 52 is placed towards the patient's
feet. As
illustrated, the anterior coronary arteries are most visible. The surgical
deflector
tool 100 is subsequently deployed.
As further illustrated in Figures 2 and 3, a first embodiment of a
surgical deflector tool 100 according to the present invention is comprised of
a
sheet-like deflector baffle 110 and a securing mechanism in the nature of a
cam
assembly 120. Surgical deflector tool 100 is capable of simultaneously
engaging
more than one surgical suture 10, for example as illustrated in Figure 2, two
such
surgical sutures 10. Sheet-like deflector baffle 110 is configured in an
inverted T-
shape profile. The longitudinal axis of horizontal elongate deflection member
111 of
the inverted T-shape is formed in a substantially arcuate shape of similar
curvature
to the arc of the retractor spreader arm 8 when said retractor spreader arm is
viewed
from above the surgical window. The longitudinal axis of the vertical
connection
member 112 of inverted T-shape is also bent in a substantially arcuate shape
to
conform closely to the shape and curvature of blade 8 so as to create the
minimum
obstruction within the surgical window when said deflector tool 100 is in use
and
engaged with sternum retractor 5. When the surgical deflector tool 100 is
deployed
and secured to the retractor spreader arm 4 such that cam assembly 120 is in a
location along arcuate rail 80 approximately mid way between the lateral ends
of
arcuate blade 8, at least a portion of horizontal deflection member 11 l, and
more
specifically at least a portion of its contours 114 and 115, are preferably
tucked
below blade 8 and laterally outward away from the verticalized beating heart
VBH.
When viewed from above the surgical window, at least a portion of said
deflection
member 111 would not be visible since it is hidden by blade 8 and in a
position
laterally outward beyond the retracted sternum half. This is further
illustrated in
Figure 12A with cam assembly 120 replaced by a variant securing mechanism in
the
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nature of T-nut assembly 710. In Figure 12A, only a portion of retractor arm 4
and
blade 8 is shown between break lines 801 and 802.
Cam assembly 120 is comprised of a clamping knob 130, a wave spring
washer 140, and a cam 150. The mechanical assembly of surgical deflector tool
100
consists of inserting cam shaft 152 of cam 150 through hole 116 in baffle 110
and
subsequently through hole 141 in wave spring 140. Cam shaft end 152 is then
rigidly engaged with knob 130 either through a press fit, or secured by a set
screw
(not shown), or by brazing, or by other like means. Once mechanically
assembled,
the cam 150 and knob 130 are free to rotate relative to baffle 110 and wave
spring
140.
Cam 150 is configured with two diametrically opposite ramp-like cam
surfaces 153, 154. The narrower width 156 of cam 150 allows it to be inserted
within passage 81 (or 71 or 51) when its length 157 is aligned substantially
tangent
to the longitudinal axis of said passage. Once cam 150 is inserted within said
passage, face 117 of baffle 110 rests on top of rail 80 (or 70, or SO), and
deflection
member 111 becomes engaged with and deflects one or more surgical sutures 10
that
come in contact with its contact surface 113 during use. A clockwise rotation
of
knob 130 will simultaneously rotate into engagement the ramp-like surfaces
153, 154
of cam 150 with faces 83 of arcuate passage 81. Similar faces to face 83 exist
in
longitudinal passage 51. Height 155 of cam 150 is inferior to height 84 of
passage
81 to allow free rotation of said cam within said passage 81 (71 or 51) and,
when
installed, to not interfere with surgical sutures 10 that may be placed within
slit-like
channels 82 (or 72). Clockwise rotation of knob 130 engages cam surfaces 153,
154
to faces 183 of passage 81 thereby causing wave spring 140 to be progressively
compressed and flattened thereby exerting a clamping load on baffle110 in the
vicinity of perimeter of hole 116. Once engaged, cam shaft 152 is in tension
while
baffle 110, wave spring 140 and rail 80 are in compression and clamped between
knob face 131 and a portion of ramp-like cam surfaces 153, 154.
Counterclockwise
rotation of knob 130 disengages the cam surface 153, 154 and relieves the
clamping
load. As such, surgical deflector tool 100 is slidingly engaged within passage
81 (or
71 or S 1 ) and may be repositioned in-process along the entire length of rail
80 (or 70
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or 50) without withdrawal of cam assembly 120 from within passage 81 (or 71 or
SO).
A texture may be configured on the contact surface 113 of baffle 110 to
tend to improve adherence between surgical suture 10 and said contact surface
113
when the surgical deflector tool 100 is deployed (or when applicable, between
retracted pericardium tissue PCT in the vicinity of surgical suture 10 and
said
contact surface 113). Said texture may be provided in the nature of gradual
ridges,
depressions, dimples, channels, grooves or other like features disposed on at
least a
portion of contact surface 113. This texture is schematically represented in
Figure
12A as feature 118 on a portion of contact surface 113 of baffle 110.
Alternatively,
said texture may also be comprised of a biocompatible hydrogel coating or
friction-
enhancing polymer or elastomer. If advantageous, this said texture may be
configured on the contact surfaces of other deflection members described in
other
embodiments or variant according to the present invention.
In another example of a usage of the surgical deflector tool 100
according to this first embodiment of the present invention, the surgical
deflector
tool 100 may be used without tissue retraction means. In this method of use,
the
surgical deflector tool 100 serves the purpose of deflecting or constraining
the
patient's expanding breathing lung in a position away from the patient's heart
thereby tending to improve the surgical access and surgeon visibility to the
patient's
heart during a cardiac surgical intervention and tending to avoid the need for
lung
deflation to increase surgical access. This also tends to avoid the need for
assistant-
hand-held tissue retractors in order to obtain the desired surgical access.
Figures 4 - 6 illustrate a second embodiment according to the present
invention. A surgical deflector tool 200 is comprised of a rod-like deflector
205, a
securing mechanism in the nature of a threaded clamp 230, and an adjustment
mechanism in the nature of a wedge pin assembly 250.
Rod-like deflector 205 consists of a substantially arcuate elongate
deflection member 210 and arcuate connection member 220, joined in
substantially
perpendicular end-to-side mechanical joint 215. Mechanical joint 215 is
preferably
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rigid. It may form a permanent assembly between members 210 and 220 such as
may be achieved through a weldment, a brazed joint, or other like means.
Alternatively, it may form a demountable joint such as may be achieved through
a
threaded interface, bolted assembly, riveted assembly, or other like
mechanical
joining means. The horizontal-spanning deflection member 210 is configured
with a
substantially circular cross section and radius of curvature R1. The vertical-
spanning connection member 220 is illustrated with a substantially rectangular
cross-
section and radius of curvature R2. The cross-section profile of connection
member
220 is configured with at least a flat portion along outboard substantially
cylindrical
surface 221 serving as a rolling surface suitable for engagement with wedge
pin 251.
The remaining cross-section profile of member 220 will be slightly inwardly
offset
from the mating cross-section profile of housing passage 246 through housing
240 to
create a slight clearance that allows relatively free arcuate translation of
member 220
through housing 240 when wedge pin 251 is disengaged from contact with either
outboard surface 221 or wedge surface 245 in housing 240. These said cross-
section
profiles must be such to achieve anti-rotation of cross-section of member 220
relative to cross-section of housing passage 246.
Housing 240 is configured with two passages, one in the form of a hole
to engage with threaded clamp 230, the other in the form of an arcuate housing
passage 246 to engage rod-like deflector 205. Arcuate passage 246 and wedge
surface 245 are machined out of housing 240 and preferably permanently capped
by
face plate 241. Once housing 240 and face plate 241 are assembled, wedge pin
251
is inserted through an opening in housing 240, transverse to arcuate passage
246, and
through a similar opening in face plate 241 that is in-line with opening in
housing
240. Wedge pin 251 is configured with two actuation wheels 252, 253. One
actuation wheel 252 may be integral to wedge pin 251 while the opposing
actuation
wheel 253 is engaged with wedge pin 251 only after said wedge pin is inserted
through openings in housing 240 and face plate 241. Wedge pin 251 is thereby
slidingly and rotatingly engaged with housing 240.
Flat face 280 on housing 240 rests atop of the arcuate rail 80 (or 70 or
50) when the surgical deflector tool 200 is secured relative to sternum
retractor 5.
Flat face 280 is offset towards bottom of arcuate passage 80 to create
substantially
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rectangular-sided anti-rotation island or dog 247 which is inserted between
lateral
faces of passage 80 (or 70 or 50). Anti-rotation dog 247 maintains
longitudinal axis
of connection member 220 in a substantially perpendicular orientation to
arcuate rail
80 and provides the anti-rotation feature to react the tightening torque
applied to
knob 230. Flat face 280 is offset upwards away from arcuate passage 81 to
define
face 242. Resulting thickness between face 242 and 280 defines flange 243
through
which a hole is machined to engage threaded clamp 230.
Threaded clamp 230 is comprised of a threaded knob 231, and
clamping plate 233 with integral threaded shaft 232. Threaded shaft 232 is
inserted
through hole in flange 243 and engaged with threaded knob 231 to form a
demountable mechanical assembly. Clamping plate 233 is configured with
dimensions that allow it to slide freely, together with surgical deflector
tool 200,
through passage 81 (or 71 or 51 ) when threaded knob 231 is not tightened.
Clamping plate 233 is preferably configured with a rectangular profile when
viewed
along the axis of threaded shaft 232. The narrower width of this rectangular
profile
is slightly smaller than the width of passage 80 (or 70 or 50) at its
narrowest topmost
location. The longer width of this rectangular profile is slightly longer than
the
width of passage 80 (or 70 or 50) at its widest bottommost location. This
allows the
clamping plate 233 to be inserted into passage 80 by vertically bringing into
contact
face 280 of surgical deflector tool 200 with rail 80 of sternum retractor 5
when
narrower width of said rectangular profile is aligned with width of said
passage 80.
With face 280 in contact with top face of rail 80, a rotation of threaded knob
231
may at first rotate threaded shaft 232 until clamping plate 233 is rotated
into contact
with the sides of passage 80 thereby providing an anti-rotation feature
allowing the
further rotation of knob 231 to apply a clamping load across flange 243 and
rail 80.
At this point, surgical deflector tool 200 is secured relative to sternum
retractor 5.
Other variants for a securing mechanism in the nature of a threaded clamp are
possible and will be described more fully below.
Figure 6A illustrates surgical deflector tool 200 secured to sternum
retractor 5, with its deflection member 210 in slight contact with a tissue
retraction
means in the nature of surgical suture 10, but prior to the deployment of the
surgical
deflector tool 200. This is referred to as the initial, non-deployed
configuration of
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said deflector tool. The tensile retraction load exerted on the PCT by the
surgical
suture 10 is secured relative to sternum retractor 5 by surgical clamp 9 (not
shown in
Figures 6A - 6B) at a suitable anchoring point (labeled AP). As such, said
suture 10
is in tension by virtue of its simultaneous engagement with retracted
pericardium
tissue PCT and said sternum retractor. To deploy surgical deflector tool 200,
the
surgeon applies a manual push load at proximal end 222 of arcuate connection
member 220, thereby causing a clockwise arcuate translation of said member 220
through passage 246 of housing 240. As a result, deflection member 210 will
apply
a deflection load to at least one surgical suture 10. As deflection member 210
tries
to deflect surgical suture 10, the tissue retraction load which the said
surgical suture
is already applying to the PCT will tend to resist said deflection and want to
rotate in
an opposing counterclockwise rotation member 220 through housing 240 when the
said surgeon-applied load is sufficiently decreased or removed. As such, when
the
surgeon releases proximal end 222, there will be a slight counterclockwise
rotation
of member 220 thereby entraining wedge pin 251 to substantially roll along
outboard
surface 221 of arcuate member 220 and become wedged between housing face 245
and said surface 221. This wedging action stops the counterclockwise arcuate
translation of said member 220 through said housing 240. Consequently, the
position of rod-like deflection member 210 is set relative to housing 240 and
sternum
retractor 5, thereby also deflecting surgical suture 10 the desired amount.
Clockwise
and counterclockwise directions are defined relative to Figure 6A - 6B.
During the course of a surgical intervention, if it is desired to increase
the deflection on surgical suture 10 and extend arcuate rod 210 deeper into
chest
cavity and laterally outward below the patient's ribcage and away from VBH, a
manual push load is re-applied to proximal end 222 to overcome the resistance
load
exerted by surgical suture 10 on deflection member 210. By this action, wedge
pin
251 is un-wedged as it rolls over contact surface 221 allowing clockwise
arcuate
translation of member 220 relative to housing 240. Once the desired position
is
obtained, releasing proximal end 222 will cause a very slight counterclockwise
arcuate translation of member 220 through housing passage 246 thereby re-
engaging
wedge pin 251 and re-securing the position of the deployed surgical deflector
tool.
During the surgical intervention, if it is desired to decrease the deflection
on the
surgical suture 10, actuation wheel 252 or 253 may be rotated by the surgeon,
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thereby un-wedging pin 251 between contact surfaces 245 and 221, and allowing
the
arcuate member 220 to be retracted through passage 246 of housing 240 in a
counterclockwise direction. The surgical deflector tool 200 is capable of
providing
in-process readjustments to the deflection amount on the surgical sutures 10
that are
engaged with said tool 200.
Figure 6B illustrates a deployed surgical deflector tool 200 secured to
sternum retractor 5, with its deflection member 210 engaged with at least one
surgical suture 10 and having deflected said suture 10 from its initial non-
deflected
position illustrated in Figure 6A. This will be referred to as a deployed
configuration of said surgical deflector tool.
Referring to Figure 6A, Px depicts a target point on the verticalized
beating heart VBH, in the general vicinity of where a surgical intervention is
intended to take place. Distance D1 is a laterally projected distance between
the
target point Px and a surgical suture 10 applying pericardial traction. V 1 is
a vector
emanating from the engagement point (labelled as EP) of the tissue retraction
means
on the pericardium tissue, in this example the piercing point of suture 10
through
PCT. Vector V 1 is directed along surgical suture 10 in a direction generally
towards
the anchoring point AP of said suture on chest retractor 5. 01 is an angle in
the
plane containing V 1 and Px, between vector V 1 and the heart surface profile
HSP
that is seen in said plane containing V 1 and Px.
Often times in a retracted chest cavity, the laterally projected distance
D1 may be small and restrictive for certain types of surgical interventions.
For
instance, in a beating heart revascularization of a posterior coronary artery,
this
distance D 1 may be small or restrictive that it may hinder not only the
deployment of
a coronary stabilizer that serves to immobilize the portion of beating heart
around
the said posterior target artery in the vicinity of point Px, but it may also
compromise the quality of the posterior artery bypass graft. The intended
benefit
that may be obtained by deploying a surgical deflector tool 200 is illustrated
in
Figure 6B. This intended benefit also applies to other embodiments according
to the
present invention.
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With the deployment of surgical deflector tool 200, vector V 1 is
redirected to become vector V2. Laterally projected distance D1 is increased
to D2
as at least a portion of the surgical suture 10 engaged with the pericardium
tissue is
moved laterally away from the heart surface profile HSP at location of target
point
Px. Angle 01 also increases to 82 as vector V 1 is redirected to assume a more
perpendicular orientation, V2, relative to the heart surface profile HSP. The
increase
in distance D 1 to D2 tends to improve surgical access and surgeon's vision at
the site
of an intended surgical intervention in the vicinity of point Px. It also
tends to
facilitate the deployment of a coronary stabilizer and the posterior artery
bypass
grafting procedure. The surgical field in the vicinity of Px is thereby
increased.
Depending on the magnitude of surgical suture deflection desired, the
deployment of surgical deflector tool 200 may also assist in further
verticalizing the
apex APX of the heart, or cause a substantially clockwise rotation of the
verticalized
beating heart VBH tending to improve access to Px. This clockwise rotation is
in
reference to the Figures 6A and 6B.
In broad terms, a surgical procedure for a set-up and deployment of a
surgical deflector tool 200 utilized in a beating heart CABG surgery, and
relating to
the present invention consists of:
(a) performing a full or partial midline sternotomy incision;
(b) cauterizing of any bleeding vessels subsequent to the sternotomy incision;
(c) if an internal thoracic artery (ITA) will be used as a bypass conduit,
retracting
the two halves of the patient's incised sternum with a surgical retractor
suitable
for exposing the ITA and the surgical harvesting thereof;
(d) retrieving the surgical retractor used for ITA harvesting, and inserting
blades 7
and 8 of sternum retractor 5 along the sternotomy incision;
(e) retracting the patient's ribcage to expose the internal thoracic cavity,
mediastinal space, and pericardium tissue PCT;
(f) incising the pericardium sac to expose at least a portion of the patient's
beating
heart containing the target coronary artery in need of a bypass graft;
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(g) engaging tissue retraction means with a portion of the patient's incised
pericardium tissue, as for example by piercing the pericardium tissue PCT with
needle 11 of surgical suture 10 at point EP;
(h) applying tensile traction loads to the surgical suture 10 to position or
orient the
patient's beating heart through the retraction of pericardium tissue
anatomically
attached to said beating heart;
(i) to perform bypass grafts on the inferior or posterior coronary artery
beds,
preferably placing the beating heart in a verticalized position with the
longitudinal axis of the heart assuming a substantially vertical orientation
through the rotation of the apex of the heart relative to the base of the
heart
outwardly through the retracted ribcage;
(j) maintaining the pericardial retraction loads, and in part the position and
orientation of the beating heart, by securing surgical suture 10 to a
substantially
stable surgical platform such as sternum retractor 5;
(k) securing surgical deflector tool 200 relative to the sternum retractor S
at a
location along one of the perimeter rails 70, 80, or 50 such that the
subsequent
deployment of said deflector tool 200 will result in the engagement of
deflection member 210 with at least one surgical suture 10 and subsequently
the
deflection of said surgical suture 10;
(1) deploying the surgical deflector tool 200 by applying a manual push load
to the
proximal end 222 of arcuate connection member 220 resulting in an arcuate
translation of said member 220 through housing 240 and a simultaneous
movement of deflection member 210 which causes the deflection of surgical
suture 10;
(m) within the enlarged surgical field created by the deflection of surgical
sutures
10, deploying a coronary stabilizer to immobilize a portion of the beating
heart
in vicinity of Px;
(n) performing arteriotomy, anastomosis, and other surgical interventions on
the
target coronary artery;
(o) verifying the quality of the bypass graft by Doppler ultrasonography, or
other
like means, and redoing the bypass graft if not satisfied with the flow
quality
through the said bypass graft;
(p) disengaging the coronary stabilizer, or other like means, from the surface
of the
beating heart after the completion of the bypass graft;
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(q) retrieving surgical deflector tool 200 from its deployed configuration to
its non-
deployed configuration;
(r) disengaging securing mechanism of surgical deflector tool 200, and
retrieving
said tool 200 from sternum retractor 5;
(s) disengaging tissue retraction means from pericardium tissue thereby
removing
the pericardial traction loads;
(t) delicately easing the beating heart back to into its substantially
horizontal
anatomic position within the retracted chest cavity;
(u) if desired, re-wrapping the incised pericardium tissue over patient's
heart and
securing said halves of incised pericardium to each other through the
placement
of surgical sutures;
(v) installing chest drainage tubes;
(w) closing retractor arms 3 and 4 and retrieving sternum retractor 5;
(x) closing the full or partial midline sternotomy incision.
The surgical procedure defined above, in broad terms also applies to
the other embodiments of a surgical deflector tool according to the present
invention,
with the exception of specific references to the constituent components of
surgical
deflector tool 200.
Figures 7, 8A and 8B illustrate a third embodiment according to the
present invention. A surgical deflector tool 300 is comprised of a rod-like
deflector
305, a securing mechanism in the nature of a threaded clamp 330, and an
adjustment
mechanism in the nature of a ratchet mechanism 350. Threaded clamp 330 is
similar
to threaded clamp 230 in the second embodiment.
Rod-like deflector 305 consists of a substantially arcuate elongate
deflection member 310 and an arcuate connection member 320, preferably rigidly
attached to said deflection member at its mid-span location. Rod-like
deflector 305
is similar to rod-like deflector 205 except for outboard surface 221 of the
second
embodiment which is replaced by a toothed surface 321. Housing 340 is also
similar
to housing 240 of the second embodiment except for the provisions to receive
an
adjustment mechanism in the nature of a ratchet mechanism 350 instead of the
wedge
pin assembly 250 of the second embodiment. Ratchet mechanism 350 prevents the
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counterclockwise arcuate translation of connection member 320 through housing
passage 346 unless the surgeon depresses lever 353 of pawl 357. Depressing
lever
353 rotates pawl 357 out of engagement with the teeth on toothed surface 321
of
connection member 320, thereby allowing the free arcuate translation of member
320
S through housing 340. When deploying the surgical deflector tool 300, the
surgeon
applies a manual push load on the proximal end 322 of arcuate member 320. This
manual push load causes the pawl 357 to rotate slightly as it disengages one
tooth
and engages the next tooth on toothed surface 321 of connection member 320.
The
counterclockwise rotation of pawl 357 is reacted in part by the spring preload
imposed on it by spring element 351. Spring element 351 is attached to housing
340
through two mechanical fasteners or pins 352. Spring element 351 keeps the
pawl
357 in contact with the toothed surface 321 and only allows clockwise arcuate
translation of connection member 320 through housing 340 unless the action of
the
spring loaded pawl is manually overriden by depressing lever 353 at which
point the
connection member 320 is free to rotate in either a clockwise or
counterclockwise
arcuate translation.
Figures 9A - 9C illustrate a fourth embodiment according to the
present invention. A surgical deflector tool 400 is comprised of an arcuate
elongate
deflection member 410, a securing mechanism in the nature of two threaded
clamps
430, a first connection member in the nature of a yoke support frame 420, and
a
second connection member in the nature of a pivot support frame 440. Threaded
clamp 430 is similar to threaded clamp 230 in the second embodiment.
Variations of
threaded clamps which may apply this embodiment, or to some or all of the
embodiments according to the present invention, are illustrated and described
more
fully below.
The two threaded clamps 430 are slidingly engaged within rails 80, 70
or 50 of sternum retractor 5. The two threaded clamps 430 are rotatingly
engaged
with their respective support frames 420 or 440. Once the desired position for
the
support frames 420 and 440 along the said rails is determined, the threaded
clamps
430 are secured to the sternum retractor 5. The distance between both support
frames 420 and 440 is variable depending on the surgical set-up and the number
of
tissue retraction means, for example surgical suture 10, to be engaged and
deflected.
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Deflection member 410 is preferably formed in an arcuate shape of similar
curvature
to the arcuate spreader arms 3 and 4 when viewed from the top of the surgical
window. The outboard surface 411 of member 410 is configured with a number of
ridges or depressions which tend to improve adherence with tissue retraction
means
when said tissue retraction means is deflected by the deployment of surgical
deflector tool 400. The ridges or depressions are preferably oriented such
that their
longitudinal axes are substantially parallel to the centerline defining
arcuate
curvature of member 410. Alternatively, outboard surface 411 may be configured
with a texture to tend to improve adherence with said tissue retraction means.
Hole 441 in the proximal end of pivot support frame 440 rotatingly
engages threaded clamp 430. The distal end of pivot support frame 440
pivotingly
engages one end of deflection member 410. Threaded hole 444 in support frame
440
is engaged by a screw 414 after said screw 414 is inserted through hole 413 in
member 410. Screw 414 acts as an axis of rotation, or pivot axis, for
deflection
member 410 when it pivots about the support frame 440. The other end of
deflector
member 410 is slidingly engaged in support frame yoke 427 configured at the
distal
end of support frame 420. A spring member 423 is housed in hole 424 in distal
end
of support frame 420, and energizes detent member 422. Detent member 422 will
engage dimple 412 in deflection member 410 when said member 410 is inserted
into
yoke 427. The spring load exerted by detent member 422 on dimple 412 must be
sufficient to keep deflection member 410 engaged within yoke 427 when the
surgical
deflector tool 400 is deployed and the deflecting load is applied to tissue
retraction
means. Alternatively, the detent member 422 may also be replaced by a pull-out
pin
or key, and dimple 412 replaced by a hole or keyway, respectively.
Support frame 440 is preferably configured with a generally arcuate
shape in the vertical direction as illustrated in Figure 9B, in order to clear
the profile
of blade 8 when support frame 440 is engaged with, and secured to, sternum
retractor
5 through rail 80. Similarly, support frame 420 is preferably configured with
a
generally arcuate shape in the vertical direction as illustrated in Figure 9C,
in order
to clear the profile of blade 7 when support frame 420 is engaged with, and
secured
to, sternum retractor 5 through rail 70. Surgical deflector tool 400 is
illustrated in
Figure 9A with both support frames 420 and 440 engaged in rail 80 through
threaded
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clamps 430. Alternatively, it may be deployed with both said support frames
engaged in rail 70, or rail 50. Alternatively, it may be deployed with one
said
support frame engaged in a different rail than the other cooperating support
frame.
Pivot support frame 440 facilitates this since the deflection member 410 may
assume
a variety of angular orientations relative to pivot support frame 440 in order
to
engage yoke 427 of support frame 420 at its free end when both support frames
are
not on a common rail. The pivoting action of deflection member 410 may also
allow
it to engage a tissue retraction means and progressively deflect it as it
pivots about
screw 414 and finally comes to engage its free end with yoke 427.
As illustrated in Figure 9A, deflection member 410 is engaged at each
of its free ends with a connection member or support frame. As such, the
engaged
tissue retraction means lie, in use, between said connection members.
Alternatively,
the yoke support frame 420 may engage deflection member 410 in any one of its
dimple 412 locations, for instance dimple location 415. As such, a portion of
the
deflection member 410 lies between the two said connection members, while a
portion may lie cantilevered beyond the yoke support frame 420 but still able
to
deflect a surgical suture 10, if so engaged, over this said cantilevered
portion.
Figures 10A - l OC illustrate a fifth embodiment according to the
present invention. A surgical deflector tool 500 is comprised of a louver-type
deflector 510, a securing mechanisms in the nature of two threaded clamps 530,
two
support frames 520 and 540, and an adjustment mechanism in the nature of
threaded
member 590. Threaded clamp 530 is similar to threaded clamp 430 in the fourth
embodiment. Support frames 520 and 540 engage sternum retractor 5 in a similar
fashion and provide similar functionality as support frames 420 and 440 in the
fourth
embodiment except for differences at their distal ends where they engage
louver-type
deflector 510.
Louver-type deflector 510 is configured as a flat plate of thickness T
and width W. A width W to thickness T ratio of approximately 4 to 7 is
generally
preferred. Two cylindrical extensions extend laterally beyond the length of
louver
S 10 in opposing directions. One cylindrical extension is comprised of a
shoulder
51 S and a shaft member 516 which becomes rotatingly engaged with boss 521 on
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support frame 520. The other cylindrical extension is comprised of a shoulder
511, a
shaft member 512 which becomes rotatingly engaged with boss 541 on support
frame
540, and a thread 513 for engagement with threaded member 590. The centerline
of
both said cylindrical extensions are coincident to each other and define the
pivot axis
of louver-type deflector 510. This pivot axis is preferably offset a distance
of O.ST -
1T in board from the width of said louvre-type deflector 510.
Boss 541 is pivotingly engaged to support frame 540 through pivot
joint 549 (schematically represented as a trapped disc within a cylindrical
bore
arrangement) and similarly boss 521 is pivotingly engaged to support frame 520
through pivot joint 529. This allows the centerlines of hole 542 and
centerline of
hole 522 to pivot freely about their support frames 540, 520 and always become
aligned relative to each other in order to engage shaft 512 and shaft 516
regardless of
the position of support frames 520 and 540 along rail 80, 70, or 50, or any
rail
combination thereof. For instance, frame 540 may be engaged in rail 80 while
cooperating frame 520 is engaged in rail 50, or frame 540 is engaged in rail
50 and
frame 520 is engaged in rail 70, or with spreader arms 3, 4 sufficiently close
together, frame 540 may be engaged in rail 70 and frame 520 is engaged in rail
80.
With reference to Figure IOB, the louver-type deflector 510 is
illustrated in its non-deployed configuration or state (drawn in solid line)
and a
deployed configuration or state (drawn in dashed line). In its non-deployed
configuration, deflector 510 is in slight contact with surgical suture 10
which
assumes an initial non-deflected vector direction V 1 when engaged
simultaneously
with PCT and sternum retractor S. In a deployed configuration, deflector 510
is
engaged with surgical suture 10 which assumes its deflected vector direction
V2.
After the pericardial traction sutures 10 have been secured to the
sternum retractor in a manner as described above, the surgical deflector tool
500 is
engaged and secured in place along rail 80, for example, through threaded
clamps
530. At this point, louver-type deflector 510 is in its non-deployed
configuration or
state. To achieve the deflection of surgical suture 10, from a vector V 1 to
vector V2
orientation, louver-type deflector 510 is rotated by the surgeon (clockwise
with
reference to Figure 10B) until the desired surgical suture 10 deflection is
achieved.
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At this point, threaded member 590 is tightened thereby clamping the lateral
faces of
boss 541 between shoulder 511 and lateral face of threaded member 590. This
secures the louver-type deflector in a desired angular orientation about its
pivot axis.
In-process readjustments may be made by the surgeon by loosening threaded
member
590, readjusting the angular orientation of louver-type deflector 510 about
its pivot
axis, and re-tightening said threaded member 590. As such, deflector 510 may
be set
in a continuously variable range of angular orientations. Alternatively, other
types
of adjustment mechanisms may be used in place of threaded member 590. For
instance, a ratchet mechanism consisting of a pawl housed in boss 541 that
engages
with teeth added to outer surface of shaft 512 may also be used, or other like
adjustment mechanisms.
Figures 11A - 11F illustrate a sixth embodiment according to the
present invention. A surgical deflector tool 600 is comprised of a deflection
member
in the nature of a continuous strip or band-type deflector 610, a securing
mechanisms
in the nature of a plurality of threaded clamps 630 (four illustrated), a
plurality of
connection members or support frames 640, 650, 660, 670, and an adjustment
mechanism in the nature of a worm-gear assembly 690. Threaded clamp 630 is
similar to threaded clamp 430 in the fourth embodiment. Support frames 640,
650,
660, and 670 engage sternum retractor S in a similar fashion as support frames
420
or 440 in the fourth embodiment.
Continuous band-type deflector 610 is intended to simultaneously
engage and deflect all surgical sutures 10 that may be deployed and secured
around
the perimeter of sternum retractor 5. Deflector 610 is rigidly engaged to
flange 641
of support frame 640 by either a welded joint or a mechanically fastened joint
or
other like means. Deflector 610 is preferably a sheet metal strip configured
with a
rectangular cross-section. The thickness of said deflector is considerably
narrower
than its cross-sectional height. This provides flexibility along the length of
the
deflector and substantial rigidity along the height of the deflector.
The band-type deflector 610 is free to slide through rectangular
opening 652 in flange 651 of support frame 650, free to slide through
rectangular
opening 662 in flange 661 of support frame 660.
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Support frame 670 is configured with a housing 671 that contains
worm-gear assembly 690 rotatingly engaged within cylindrical opening 673. Band-
type deflector 610 is not free to slide through rectangular opening 672 of
housing
671, but may translate through said rectangular opening 672 by virtue of a
rotation
of knob 680 which rotates helical worm 682 thereby entraining serrations 611
and
the said translation of deflector 610.
Each support frame has a substantially flexible portion 649, 659, 669,
and 679 along its arcuate vertical length. With the threaded clamps 630
securing the
position of their respective support frames 640, 650, 660, and 670 on the
rails 80, 70,
and 50 of sternum retractor 5, rotating knob 680 in one direction causes the
length of
band-type deflector 610 between flange 641 and housing 671 to increase. The
flexible portions 649, 659, 669, and 679 will consequently flex in a direction
laterally away from the patient's beating heart (or the center of the
retracted chest
opening), thereby also tending to increase the amount of deflection
simultaneously
exerted on the plurality of surgical sutures 10 that may be deployed and
secured
along the perimeter of sternum retractor 5. During the flexing of support
frames 650
and 660, the deflector 610 slides through the openings 652 and 662 of said
support
frames 650 and 660.
Figures 12 - 17 illustrate a variety of different securing mechanism.
Figures 12A-12B illustrate a securing mechanism in the nature of a T-nut
assembly
710 comprising T-nut 712 and co-operating bolt 711. In this embodiment, the T-
nut
712 is installed into arcuate passage 81 (or 71 or 51). Then, contact surface
113 of
baffle 110 is brought into contact with one or more tissue retraction means.
The
tissue retraction means is deflected until a hole in said baffle is aligned
with
threaded hole in T-nut 712. Bolt 711 is then engaged with co-operating T-nut
712
and baffle secured in place by the resulting clamping force between the said T-
nut
712 and bolt 711. Baffle 110 may also be configured with more than one hole in
its
connection member 112 to provide variability in the secured position of the
deflecting contact portion 113 relative to the said sternum retractor.
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Figures 13A-13B illustrate a securing mechanism in the nature of a
modified T-bolt assembly 720 comprising T-bolt 722 and co-operating nut 721.
The
parallelogram shape of the modified T-bolt 722 allows the deflector baffle 110
to
become engaged with and secured relative to rail 80 (or 70 or SO) through a
clockwise rotation of nut 721 without having to first slide bolt 722 into
arcuate
passage 81 (or 71 or 51). When bolt 722 is aligned lengthwise with arcuate
rail 80
(orientation 723), it may be inserted into arcuate passage 81. A clockwise
rotation
of nut 721 will cause bolt 722 to rotate clockwise up until its short faces
are in
substantial contact with the lateral faces of arcuate passage 81 (orientation
724). As
a result, a portion of parallelogram shaped top face of T-bolt 722 comes into
contact
with faces 83 of rail 80. A further rotation of nut 721 will clamp deflector
baffle
110 between nut 721 and top of rail 80.
Figures 14A-14B illustrate a securing mechanism in the nature of a
radial engaging cam 730 comprising a radial engaging cam 733, a shaft 735, a
wave
spring washer 732 and a securing knob 731. Radial engaging cam 730 is
rotatingly
engaged with deflector baffle 110 to form an intergral mechanical assembly.
The
deflector baffle 110 is secured relative to sternum retractor 5 within arcuate
passage
81 when knob 731 is rotated thereby radially engaging the two opposing cam
surfaces 734 with the lateral walls 899 defining arcuate passage 81 (or 71 or
51).
The clamping load on baffle 110 is provided by compressing wave spring 732.
Figures 15A-15B illustrate a securing mechanism in the nature of a
grommet-type expansion joint 740 comprising a bolt 741, an elastic annular
washer
742, and a clamping plate 744. Prior to installation, clamping plate 744 is in
substantial contact with elastic washer 742. Once the grommet-type expansion
joint
740 is inserted into arcuate rail 80 (or 70 or SO) a rotation of bolt 741
produces an
axial compression of washer 742 and a simultaneous radial expansion of washer
742.
This radial expansion produces the engagement between washer 742 and the
lateral
walls of arcuate passage 81 (or 71 or 51). The friction between clamping plate
744
and elastic washer 742 keeps said plate 744 from rotating relative to said
washer 742
when knob 741 is tightened.
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Figure 16 illustrates a securing mechanism in the nature of a C-shaped
flange 750 comprising a bolt 754, two extensions 753 and 752, and a joining
section
751. Deflector connection member 112 is engaged with rail 80 of sternum
retractor
through a clockwise rotating motion that brings into contact extension 752
with
S underside surface 83 in arcuate passage 81. Bolt 754 is subsequently
tightened to
prevent a reverse counterclockwise rotating motion and disengagement of said
connection member and consequently the surgical deflector tool.
Figure 17 illustrates a securing mechanism in the nature of a retention
clip 760. Deflector baffle 770 is inserted into arcuate passage 81 (or 71 or S
1 )
through the engagement of anti-rotation block 772 extending from flat surface
771.
Retention clip 760 is then installed such that its surfaces 761 and 762
simultaneously
contact the bottom surface of retractor arm 4 and the top surface 771 of
baffle 770.
Figures 18A - 18C illustrate a seventh embodiment according to the
present invention. Surgical deflector tool 800 is comprised of an elongate rod-
like
deflection member 801, an arcuate connection member 810 and a securing
mechanism 860. Deflection member 801 is preferably configured with an arcuate
shape similar in shape to that of the arcuate shape of retractor spreader arm
4.
Deflection member 801 is comprised of a free end 802 and a joined end 803 that
is
preferably rigidly connected to distal joined end 813 of connection member
810,
such as through a press fit interface, a weldment, a brazed joint, a
mechanical
fastener joint, or any other like rigid connection joint. As such, when
joined,
connection member 810 and deflection member 801 form an integral assembly that
is
substantially L-shaped (as opposed to the second embodiment where said
deflection
and connection members form an integral assembly that is substantially
inverted T-
shaped). For ease of manufacturing, connection member 810 is preferably an
arcuate
sector of a metal ring or metal annulus. The cross-section through connection
member 810, generated by a cut normal to the arcuate shape, is rectangular in
shape.
Securing mechanism 860 forms a demountable mechanical assembly
and is comprised of a slotted articulation cylinder 830, two opposing co-
operating
jaws 820, 840, a housing sleeve 850, and a securing knob 870. A longitudinal
axis
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861 helps define the securing mechanism 860 and its components, along with the
longitudinal direction through said components.
Articulation cylinder 830 is defined by a centerline axis 832 (seen in
end view in Figure 18B). A transverse arcuate slot 831 is disposed
substantially
along a diameter of said cylinder. As such, two opposing cylindrical contact
surfaces 833, 834 and two opposing arcuate internal contact surfaces 835, 836
are
created. In use, slot 831 will engage a portion of connection member 810. A
mechanical load applied across contact surfaces 833, 834 will deform slot 831
in a
manner that a compressive force will be transmitted to the engaged portion of
connection member 810 within slot 831 through arcuate contact surfaces 835,
836.
Jaws 820, 840 are substantially cylindrical in shape along their
longitudinal axes. A longitudinal slot is contained within said cylindrical
shape to
create two opposing C-shaped jaws. The C-shape in each of said jaws is defined
by
a face 826 or 846, a beam 825 or 845, and a socket 824 or 844. Sockets 824,
844 are
defined by substantially cylindrical contact surfaces. Lower jaw 820 is
configured
with a spring member 823 that is energized when a mechanical load is applied
generally along the longitudinal axis of said jaw 820. When said jaws 820, 840
are
assembled, spring member 823 of jaw 820 mates with face 846 of jaw 840 and
entrains opposing sockets 824, 844 to move towards one another in a
longitudinal
direction. A central opening is created between assembled jaws 820, 840 able
to
receive articulation cylinder 830. Said opening is defined laterally by
opposing
beams 825, 845 and longitudinally by opposing sockets 824, 844. Sleeve 850 is
inserted over assembled jaws 820, 840 in a manner that external thread 843 is
inserted through hole 852 and extends beyond top of said sleeve. As such, said
thread 843 may be engaged with internal thread 871 in knob 870.
Sleeve 850 is configured with two diametrically-opposite,
longitudinally-elongate windows 851. Sleeve 850 may be rotated such that said
windows 851 become aligned with said central opening created within assembled
jaws 820, 840. Windows 851 are at least as wide as lateral width defined
between
beam portions 825, 845 of assembled opposing jaws 820, 840. Said lateral width
is
preferably only slightly wider than width of articulation cylinder 830. As
such,
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articulation cylinder 830 may be inserted through one of said windows with its
centerline axis 832 oriented substantially perpendicular to longitudinal axis
861.
After insertion, contact surface 834 is in contact with socket 824, and
contact surface
833 is in contact with opposing socket 844. As such, cylinder 830 and jaws
820, 840
co-operate to allow contact surfaces 833, 834 to rotate freely between sockets
824,
844 when knob 870 is not tightened. The proximal free end 814 of connection
member 810 can be inserted into slot 831 when said slot is visible through
window
851.
Lower jaw 820 is configured with a seat 821 and waist diameter 822
that extend below base 853 of sleeve 850 when securing mechanism is assembled.
Seat 821 and waist diameter 822 thereby allow securing mechanism 860 (and
consequently deflector tool 800) to be slidingly engaged with any of passages
81, 71,
or 51 and positioned at any location along along rails 80, 70, or 50 of
sternum
retractor 5. At any such given position along said rails, waist diameter 822
also
allows securing mechanism 860 (and consequently deflector tool 800) to rotate
freely
about its longitudinal axis 861, prior to tightening knob 870.
Alternatively, lower jaw 820 may be configured with an anti-rotation
feature at location of waist diameter 822, for instance two substantially
parallel and
opposing flats spaced apart a distance slightly inferior to the lateral width
of passage
81, 71, or 51. Said flats will mate with lateral faces of said passage to
restrict or
prevent the free rotation of securing mechanism 860 (and of deflector tool
800)
relative to sternum retractor 5. Said flats, however, allow the free
translation of
securing mechanism 860 along said rail 80, 70, or 50 when knob 870 is not
tightened.
When engaged along a rail 80, 70, or 50 of sternum retractor S,
longitudinal axis 861 of securing mechanism is substantially perpendicular to
the top
of said retractor rail in which securing mechanism 860 is engaged.
In use, connection member 810 is slidingly engaged with articulation
cylinder 830, and when securing knob 870 is not tightened, said member 810 is
free
to arcuately translate through said cylinder 830. This said arcuate
translation is
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represented schematically in Figure 18B as arrow 811. Any portion of
connection
member 810 may be engaged within slot 831, thereby providing a continuous
range
of arcuate settings (between proximal free end 814 and joined distal end 813)
that
connection member 810 may assume relative to securing mechanism 860. This also
sets the general position of deflection member 801 relative to the sternum
retractor
5, and also relative to the engaged anatomic tissue intended to be deflected.
In use, when securing knob 870 is not tightened, articulation cylinder
830 is free to rotate about its centerline 832 within the assembled securing
mechanism 860. As such, when connection member 810 is engaged within slot 831
of cylinder 830, connection member 810 is also pivotingly engaged with respect
to
securing mechanism 860 and able to pivot about centerline 832 as cylinder 830
rotates within co-operating, opposed jaws 820, 840. A continuous range of
pivot or
angular settings is offered. This said pivoting of connection member 810 is
represented schematically in Figure 18B as arrow 812. Said range of angular
settings is generally limited by the longitudinal width of window 851, or by
the
circumferential gap between assembled sockets 824 and 844. As a result, at any
given arcuate setting of connection member 810 relative to securing mechanism
860,
said member 810 may be further set or additionally adjusted in a desired
angular
setting relative to securing mechanism 860. The available range of angular
settings
allows the surgeon to set the general orientation of connection member 810 and
deflection member 801 relative to sternum retractor S, and also relative to
the
engaged anatomic tissue intended to be deflected.
When deflector tool 800 is in its non-deployed configuration, distal
joined end 813 of connection member 810 is in the vicinity of window 851, and
deflection member 801 is in the vicinity of engaged rail 80, 70, or 50. In
use, when
deflector tool 800 is in its deployed configuration, proximal free end 814 of
connection member 810 is in the vicinity of window 851, and deflection member
801
is in the vicinity of free end 85 of blade 8, or 7. To deploy said tool 800,
the
surgeon applies a manual load to free end 814 to produce an arcuate
translation and
achieve a desired arcuate setting, or applies a moment (about centerline 832)
to
connection member 810 to orient said connection member and set the desired
angular
setting, or applies a combination of said manual load and said moment. In
deploying
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deflector tool 800, the surgeon first brings into contact deflection member
801 with
at least one tissue retraction means and subsequently deflects said retraction
means
or anatomic tissue in a manner already described according to the present
invention.
When knob 870 tightened, the two opposing jaws 820, 840 co-operate
to clamp articulation cylinder 830 across its opposing contact surfaces 834,
833. A
compressive load is applied to the portion of connection member 810 engaged
within
slot 831 of said cylinder 830. As a result, (i) the arcuate translation of
connection
member 810 through securing mechanism 860 is locked and said connection member
810 is no longer slidingly free, (ii) the rotation of cylinder 830, and
pivoting of
connection member 810 about securing mechanism 860, is locked or fixed, and
(iii)
the location of deflector tool 800 along engaged rail 80, 70, or SO is locked
or fixed.
Securing mechanism 860 allows in-process readjustments to the
surgical set-up of deflector tool 800. Loosening knob 870 will allow the
surgeon to
reposition securing mechanism 860 along engaged rail 80, 70, or 50, or
reposition
connection member 810 through articulation cylinder 830, or reorient said
connection member relative to securing mechanism 860, without disengaging
deflector tool 800 from sternum retractor 5.
Figure 19 illustrates an eighth embodiment according to the present
invention. Surgical deflector tool 900 is comprised of an elongate rod-like
deflection member 901, two arcuate connection members 910, 920, and two
securing
mechanisms 930, 940. Deflection member 901 is preferably configured with an
arcuate shape and is preferably rigidly connected to each of connection
members 910
and 920. As such, when joined, connection members 910, 920 and deflection
member 901 form an integral assembly that is substantially U-shaped.
Securing mechanisms 930, 940 are schematically represented by a
housing 931, 941 and a securing member 932, 942. In this eight embodiment,
connection member 910, 920 are rigidly connected to housing 931, 941 of
securing
mechanisms 930, 940 (even when securing members 932, 942 are not actuated). As
such, securing mechanisms 930, 940 are comprised of similar components as
those
described, for instance, in the variants illustrated in Figures 13, 14, 15.
When
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securing members 932, 942 are not actuated, deflector tool 900 is free to
slide along
engaged rail 80, 70, or 50 of sternum retractor 5.
Prior to deploying deflector tool 900, the pericardium tissue PCT is
first engaged by a tissue retraction means such as surgical suture 10, said
suture is
then inserted in slit-like channel 82, and subsequently secured to a part of
the
sternum retractor 5. Said suture is usually secured under tension and
preferably
applies at least a slight retraction load on engaged PCT. The deflector tool
900 is
then deployed in a manner that deflection member 901 is brought into contact
with
and subsequently deflects at least one surgical suture 10 or a portion of
retracted
pericardium tissue PCT. The imposed deflection on surgical suture 10 or
pericardium tissue PCT is maintained by engaging securing mechanisms 930, 940
in
rail 80 (or 70, or SO) and actuating their respective securing members 932,
942. The
position of deflector tool 900 along rail 80 (or 70, or 50) may be readjusted
by
releasing securing members 932, 942 and sliding said tool 900 along said rail.
Deflection member 901 is comprised of a deflector portion which spans between
connection points 903, 904, but may also span beyond said connection points to
reach free end points 905, 906. Deflection member 901 is preferably configured
with a plurality of traction channels, slots, or grooves 902 along its contact
surface
907. Said traction grooves 902 may help to engage and laterally restrain a
tissue
retraction means as it is being deflected, or help promote adherence with
pericardium
tissue PCT when said tissue is in contact with contact surface 907 and being
deflected by said deflection member 901.
Alternatively, a variant deflector tool 900 may be comprised of two
securing mechanisms that permit the translation of connection members 910, 920
through said securing mechanisms, or permit translation and pivoting of said
connection members relative to said securing mechanisms. For example, these
types
of securing mechanisms may be comprised of similar components as those
described
in the embodiments illustrated in Figures 4, 7, 18, or any other suitable
securing
mechanism described herein. In addition, this variant may be comprised of a
tying
member 950 preferably connected to both connection members 910, 920. When this
variant is in its non-deployed configuration, said tying member 950 is in the
vicinity
of rail 80 (points 911, 912 are located in the vicinity of securing
mechanisms). As
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such, this offers a different method for securing tissue retraction means. In
certain
surgeries it may be advantageous to engage an anatomic tissue intended to be
deflected with a tissue retraction means, such as surgical suture 99, and
subsequently
securing said surgical suture 99 to a portion of the deflector tool prior to
its
deployment. For instance, prior to said deployment, surgical suture 99 may be
secured to tying member 950, preferably while said suture is under tension and
applies a retraction load to said anatomic tissue. The deflector tool is
subsequently
deployed by applying a manual load on proximal free ends 914, 924 of
connection
members 910, 920 which results in tying member 950 moving away from rail 80
within retracted chest cavity, and deflection member 901 deflecting suture 99
or
portion of pericardium tissue PCT engaged by said suture 99. Alternatively,
while
this variant is in its non-deployed configuration, pericardium tissue PCT may
also be
engaged, retracted, and secured to deflection member 901 by a surgical suture
199.
Tying member 950 is configured with a plurality of traction grooves 951 along
its
contact surface 952 which serve the same role as traction grooves 902 on
deflection
member 901.
Figure 20 illustrates a ninth embodiment according to the present
invention. Surgical deflector arrangement 1000 is comprised of a plurality of
surgical deflector tools 1100. Each of said surgical deflector tools 1100 is
further
comprised of deflection pad 1101, a connection member 1110, and a securing
mechanism 1160. Each of the deflector tools 1100 may be independently
positioned
and secured along either one of rails 80, 70, or 50, and is preferably
slidingly
engaged with said rails.
Deflection pad 1101 is preferably configured with a slot 1102 that is
well suited to laterally engage a tissue retraction means, such as suture 10,
during
intended deflection of said suture. Deflection pad 1101 may either engage and
deflect a surgical suture 10 (as in location B and C), or may engage and
deflect a
portion of pericardium tissue PCT, preferably in the vicinity of where. said
portion of
PCT is being retracted and engaged by a suture 10 (as in position A). As such,
deflection pad contact face 1103 is preferably configured with friction-
enhancing
surface texture like surface texture 118 described with reference to Figure
12A.
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Connection means 1110 is preferably arcuate in shape. Securing
mechanism 1160 is schematically represented by a housing 1161 and a securing
member 1162. Securing mechanism 1110 may represent any suitable securing
mechanism previously described in the embodiments or variants of the present
invention.
Figure 21 illustrates a surgical deflector tool 1200 with a variant
mechanical joint between deflection member 1201 and connection member 1210.
Elongate deflection member 1201 is rod-like in cross-section and preferably
arcuate
in shape. Connection member 1210 is configured with a socket 1203 at its
distal free
end. Said socket 1203 retains a split sphere 1204 therein. Said sphere 1204 is
configured with a through bore 1205 that is split lengthwise by slot 1206 that
also
extends radially outward to outer surface of said sphere 1204. Deflection
member
1201 is inserted in bore 1205 and is free to slide within said bore. Once
engaged
with sphere 1204, said deflection member 1201 is capable of pivoting relative
to
connection member 1210 within the spherical joint defined by socket 1203 and
sphere 1204. The position and orientation of deflection member 1201 relative
to
connection member 1210 may be locked or fixed by tightening a securing means
in
nature of screw 1202. As such, this variant defines a deflection member 1201
that is
slidingly and pivotingly engaged with a connection member 1210.
Figure 22 illustrates a surgical deflector tool 1300 with a variant
mechanical joint between deflection member 1301 and connection member 1310.
Elongate deflection member 1301 is rod-like in cross-section and preferably
arcuate
in shape and has a plurality of depressions or grooves 1302 disposed along its
length.
Connection member 1310 is configured with a fitting 1312 at its distal free
end.
Said fitting 1312 is configured with a through bore 1311. Fitting 1312 is
provided
with a slot or opening (not shown) that communicates with said through bore
1311.
A detent lever 1313 is pivotingly engaged with fitting 1312. Said lever is
configured
with a protrusion or latch (not shown) which extends within said slot or
opening in
fitting 1312 and engages with a groove 1302 contained along the portion of
deflection member 1301 engaged within bore 1311. Deflection member 1301 is
capable of translating freely through fitting 1312 when lever 1313 is
depressed by
the surgeon, thereby disengaging said latch from groove 1302. As such,
deflection
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member 1302 may be repositioned relative to connection member 1310. The
position of deflection member 1301 relative to connection member 1310 may be
locked or fixed by again releasing lever 1313 so that said latch engages
another
groove 1302. This variant defines a deflection member 1301 that is slidingly
engaged with a connection member 1310.
Figure 23 illustrates a surgical deflector tool 1400 with a variant
connection member in the nature of a collapsible and extendable telescopic arm
1410. Telescopic arm 1410 may be deployed in a substantially continuous range
of
variable connection arm lengths between its deflecting end 1413 and securing
end
1414. Telescopic arm 1410 is comprised of a plurality of progressively smaller
diameter tubular segments 1411 each capable of being retracted within the
lumen of
the adjacent larger diameter segment. Tubular segments 1411 are preferably
arcuate
in shape along their defining longitudinal axes. In its non-deployed
configuration,
telescopic arm 1410 is collapsed in length with deflecting end 1413 in close
proximity to securing end 1414. The surgeon deploys deflector tool 1400 by
extending telescopic arm 1410 in length until the deflection member 1401 is
placed
in contact with at least one tissue retraction means and the requisite
deflection of
said tissue retraction means is achieved at which point the telescopic arm is
fixed in
position. The tubular segments 1411 may be designed with sufficient sliding
friction
between adjacent segments such that said friction is sufficient to maintain
telescopic
arm in desired position to maintain desired deflection of tissue retraction
means.
Alternatively, a position-fixating knob 1412 may be disposed at the proximal
end of
telescopic arm 1410 to secure desired configuration of telescopic arm 1410.
The
concept of a telescopic arm may also be applied to deflection member 1401 so
that a
variable length deflection member may be deployed within the surgical
workspace to
best suit the patient anatomy or space available within the retracted chest
cavity.
Figure 24 illustrates a surgical deflector tool 1500 with a variant
connection member in the nature of a flexible, lockable arm 1510 having a
plurality
of interconnecting links 1511, 1512 which allow the positioning and
orientation of
deflection member 1501 in every direction within the surgical workspace until
the
desired configuration is achieved at which point the flexible arm 1510 may be
locked
into a fixed configuration by tightening a fixation knob 1513 attached to a
cable (not
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shown) running axially through the interconnecting links 1511, 1 S 12.
Interconnecting link 1511 is comprised of a ball portion or sphere joint which
fits
conformingly within a receiving portion or cylindrical tube of interconnecting
link
1512. When a tension is exerted on said cable, flexible arm 1 S 10 is locked
in a rigid
configuration. Alternatively, other tensioning means are also possible. For
instance,
an inflatable internal balloon that expands against the interior of said
interconnecting
links rendering the individual links immobile, and thereby locking the entire
arm
1510 into a fixed configuration, or other like means for securing
interconnecting
links of a flexible arm.
The proximate end 1514 of arm 1510 is attached to sternum retractor 5
through securing mechanism 1160. When fixation knob 1513 is not actuated,
flexible arm 1510 is deformable between points 1514 and 1502. As such, arm
1510
may assume not only an arcuate shape (as illustrated in Figure 24), but any
other
shape such as a spline, S-shape, or other variant shape which is most suited
for the
surgical field in which deflector tool 1500 will be deployed. The concept of a
flexible, lockable arm may also be applied to deflection member 1501 so that a
deformable deflection member may be deployed within the surgical workspace to
best suit the patient anatomy or space available within the retracted chest
cavity.
Figure 25 illustrates a surgical deflector tool 200 from the second
embodiment, engaged with a plurality of tissue retraction means in the nature
of
suction device 12. Suction device 12 is comprised of a suction port 14
(preferably
deformable) disposed at its distal free end, and a substantially flexible
hollow
conduit 13 providing a negative pressure suction force from a distal vacuum
source
to said port 14. In use, said suction device is engaged at its proximal end 15
with a
portion of passage 81, 71, or 51 of sternum retractor 5, and simultaneously
engaged
at its distal end with pericardium tissue PCT through said suction port 14.
Surgical
deflector tool 200, when deployed, serves to deflect at least a portion of
said suction
device, more specifically its conduit 13, in a similar manner as already
described in
relation to surgical suture tissue retraction means. Instead of surgical
deflector 200,
other embodiments of a surgical deflector tool already described may also be
used to
co-operate with suction device 12.
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In the embodiments of the present invention described herein, it is
intended to produce the bulk of the surgical apparatus from reusable
components,
whose assembly may be at least partially dismantled, if necessary, for ease of
sterilization. All components are manufactured in either surgical grade
stainless
steel, titanium, aluminum or any other reusable sterilizable material suitable
for
surgical use. Components that may be produced from polymeric materials are
either
reusable through specific sterilization procedures tailored to these component
materials, or must be replaced after every use or after a predetermined number
of
uses if the polymeric material properties are not suitable for sterilization
or degrade
after repeated sterilization cycles. However, any number of the said reusable
components may also be produced from disposable surgical grade plastics, if
the case
for disposable components is warranted and if the engineering and functional
intent
is maintained when the said component is produced from plastic.
The above description of the embodiments of the present invention
should not be interpreted in any limiting manner since variations and
refinements are
possible without departing from the spirit of the invention.
