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Description  |
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FIELD OF THE INVENTION
The present invention relates to retractors used in surgery, and more
specifically, to an inflatable retractor by which an internal organ or
other internal body part may be retracted during endoscopic surgery.
BACKGROUND OF THE INVENTION
The field of endoscopic surgery has been advancing rapidly in recent years.
In this form of surgery, procedures are performed inside the body of a
patient using instruments inserted through small incisions or ports in the
body. The surgery is performed with the aid of an endoscope, which is a
thin, tube-like instrument featuring a light source, viewing lenses,
and/or various other attachments such as irrigators, scissors, snares,
brushes or forceps. Endoscopes may be flexible or rigid, and normally
utilize optic fibers to transmit light to the internal cavity. The surgery
is normally viewed by the surgeon through an ocular. Lenses are placed
near the distal tip of the endoscope and the image thereon is transmitted
via optic fibers or other lens systems to the ocular or viewer. Other
types of endoscopes utilize optic fibers to transmit electronic signals
representing the internal image from the distal lens to a video monitor
which is viewed by the surgeon.
This form of surgery allows internal visualization of the body structure
without the necessity of excessive dissection of tissue. Typical
endoscopes are in the 5 to 12 mm diameter range and thus require only very
small incisions for insertion into the body.
Endoscopic surgery has developed rapidly because of the numerous benefits
arising in favor of the patient. Since there is only a small incision to
permit the entrance of the endoscope and other endosurgical devices,
endoscopic surgery results in less trauma to the patient's body and faster
patient recovery. For the benefits of endoscopic surgery to arise,
however, all aspects of the surgery, such as the initial examination,
retraction of internal organs, and the surgical procedure itself, must be
capable of being performed through small endoscopic incisions or ports.
The obvious difficulty associated with endoscopic surgery is inadequate
visualization of the internal structure required to properly complete the
surgical procedure. Endoscopic surgery is thus difficult in areas which
are typically difficult to reach, such as the gallbladder. In the surgical
removal of the gallbladder, also known as cholecystectomy, the tissue and
organs surrounding the gallbladder are examined using an endoscope and
retracted in order to properly expose the organ which is to be removed.
Currently, endoscopic procedures in the abdominal cavity, otherwise known
as laparoscopy, often require retraction. Specifically, endoscopic
procedures involving the gallbladder entail retracting the liver, which
rests directly above the gallbladder. In an open surgery procedure,
retraction such as this is relatively easy, as the surgery involves the
exposure of the entire abdominal cavity. In order to obtain the benefits
of endoscopic surgery, however, a form of retraction which can be
accomplished through endoscopic ports is necessary.
In an endoscopic procedure involving the gallbladder or other abdominal
organ, retraction is currently accomplished by inflating the peritoneal
cavity with carbon dioxide. This method of retraction requires a small
endoscopic port for the introduction of the gas source. The gas is
introduced into the body through a trocar, and a state of pneumoperitoneum
occurs. The gas inflates the peritoneal cavity so as to cause the skin and
muscles to separate from and rise above various organs and tissue,
creating the exposure necessary to accomplish the endoscopic surgery.
Several problems are associated with pneumoperitoneal retraction however.
First of all, exposure of the organs remains adequate only while the
required pneumoperitoneal state remains. Since endoscopic surgery normally
requires the introduction of at least the endoscope, and more often
several other endoscopic instruments, several endoscopic ports will most
likely be created in the patient's body. Each of these ports, which
normally use a cannula to keep them open for access, in effect create an
exhaust port for the gas. The risk that insufflation pressure may be lost
increases the risk that the endoscopic procedure may go awry as adequate
exposure for the endoscope is eliminated.
Further, there are many complications which are associated with persistent
pneumoperitoneum during an endoscopic procedure. Acute cardiovascular
collapse secondary to over-distension of the abdomen, vasovagal reflex
activation, cardiac arrhythmia, pneumothorax, subcutaneous emphysema,
alteration of large vein venous return, retinal hemorrhage, blindness,
carbon dioxide embolism, and general patient discomfort have all been
associated with persistent pneumoperitoneum.
In addition, pneumoperitoneal retraction is effective in retracting only
the muscles and tissue from above the organs. The organs themselves are
not, to a great extent, retracted from each other.
Lastly, current mechanical retractors are often made of stainless steel or
other metals. Use of metal retractors in the presence of other endoscopic
surgical tools may result in inadvertent electrical or laser injury.
Additionally, such retractors can cause inadvertent tearing, slicing,
puncture or other mechanical injury to the internal tissues and organs.
There is therefore a need for a device and method which provide retraction
in conjunction with endoscopic procedures which is effective in providing
adequate visualization and which is safe and has fewer side effects than
current retraction methods.
SUMMARY OF THE INVENTION
The present invention provides an apparatus and method for improved
endoscopic retraction procedures. The invention permits safe and effective
retraction of internal organs and tissue during an endoscopic procedure.
Retraction is accomplished with the present invention through the use of an
inflatable bladder or balloon inserted through an endoscopic housing. The
balloon is soft and flexible enough to avoid damage to internal organs and
tissues, yet it is sufficiently inelastic and rigid so as to provide
retraction when inflated.
In accordance with one aspect of the present invention, there is provided
an inflatable endoscopic retractor comprised of an inflatable balloon
having an anatomical configuration designed to retract structures specific
to the surgical procedure. For example, the balloon for use in an
endoscopic cholecystectomy would be configured to retract the liver, as
well as to protect the retracted liver and bowel. Analogous anatomical
balloons for use in laparoscopic surgery include configurations for the
kidney, bladder, pancreas, and other abdominal exposures.
This balloon is fabricated using an anatomical model of the human abdominal
cavity or other areas of the body. This model can be based upon MRI or CT
scan images of a particular patient, or the known internal structure of a
normal adult. Using the anatomical model, the balloon is configured to
retract and support the desired anatomical structure upon inflation.
When retraction during laparoscopic surgery is desired, the deflated
balloon is inserted into the body through an endoscopic tube or housing.
The balloon is slightly inflated to assist in its proper positioning
inside the body, and endoscopic forceps may be used to assist in
accomplishing such positioning. Once the balloon is in place, it is
inflated with air or other gas or liquid, in an amount sufficient to
retract the desired organ or other tissue and maintain and support the
organ or tissue in its retracted position. After the endoscopic procedure
is complete, the balloon is deflated and drawn through the endoscopic
housing, and the housing is removed.
In accordance with a second aspect of the present invention, there is
provided an inflatable endoscopic retractor comprised of an inflatable
balloon attached to a support rib that provides some strength and rigidity
for the retraction, without damaging the retracted tissues. This support
rib is pre-bent such that the rib forms an angle. The rib is constructed
of material which is sufficiently flexible to allow the rib to straighten
upon insertion of the rib into the endoscopic housing, yet rigid enough to
spring back into its angled position upon exiting the housing. This spring
bias or "give" in the retraction also provides a measure of safety for the
retracted tissues. The inflatable balloon, which is attached to the
support rib, can have any of a number of configurations, including, for
example, a spatula-like structure.
When retraction is desired, the retractor is inserted into the body through
an endoscopic housing or appropriate cannula. Once in position, the
balloon is inflated with air or other gas or liquid in an amount
sufficient to retract the desired organ or other tissue and maintain and
support the organ or tissue in its retracted position. When the endoscopic
procedure is complete, the balloon is deflated and withdrawn through the
housing, and the housing is removed from the patient's body. Two or more
of these inflatable retractors can be inserted into a single endoscopic
housing to achieve the desired retraction and support.
In accordance with another aspect of the present invention, there is
provided a method of retracting internal tissue and organs using a
retractor having an elongated housing capable of being inserted into the
body. This housing has two separate channels. The first channel is used to
guide the entry of the inflatable balloon and its attached support rib.
The second channel is used to guide the insertion of any of a number of
endoscopic instruments. Thus, the present invention provides a single
instrument inserted through a single endosurgical port which provides
retraction, as well as providing a channel for the insertion of a second
surgical tool.
In accordance with still another aspect of the present invention, there is
provided an inflatable endoscopic retractor comprised of an inflatable
balloon having multiple fingers or projections, with each projection
attached to an angled support rib that provides strength for the
retraction. The retractor is inserted into the body through an endoscopic
housing. Once in position, the balloon is inflated with air or other gas
or liquid in an amount sufficient to retract the desired organ or other
tissue and maintain and support the organ or tissue in its retracted
position. When the endoscopic procedure is complete, the balloon is
deflated and withdrawn through the endoscopic housing, and the housing is
removed from the patient's body.
The inflatable endoscopic retractor of the present invention significantly
reduces the risks associated with retraction, such as thermal, electrical,
or mechanical injury. In addition, it does not present the dangers
associated with continuous pneumoperitoneal retraction. The present
invention can be positioned with only initial insufflation to provide easy
insertion of the device. After insertion, retraction can be maintained
simply and safely with the inflatable balloon.
The inflatable retractor is advantageously very small, which allows its
introduction into the body through a housing placed in a small trocar
opening. The retractor is normally introduced through a single small
opening.
The inflatable retractor is much more effective in retracting organs,
especially larger ones, than insufflation. The invention allows the
surgeon or assistant to manually retract an organ to the extent necessary,
merely by manipulating the retractor, and/or the inflation pressure inside
the balloon. The inflatable retractor is easily manipulable into a variety
of angles and positions to provide exact retraction at any location. This
is in contrast to the insufflation method, where the gas indiscriminately
fills the body cavity. On the other hand, if desired, the present
retractor can be used in conjunction with insufflation as it is compatible
with that method.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a patient illustrating the general manner in
which the inflatable retractor of the present invention may be used during
an endoscopic procedure.
FIG. 2 is a side view of a first embodiment of the inflatable retractor of
the present invention with the endoscopic housing shown in cross section.
FIG. 3 is a schematic view of the first embodiment of the inflatable
retractor of the present invention, showing it positioned beneath the
liver, with the balloon deflated.
FIG. 4 is a schematic view of the first embodiment of the inflatable
retractor of the present invention similar to FIG. 3, but with the balloon
inflated and retracting the liver so as to expose the gall bladder.
FIG. 5 is a side view of a second embodiment of the inflatable retractor of
the present invention, showing the support rib in an angled position prior
to its insertion into the endoscopic housing, the deflated balloon
attached to the support rib, the inflation and deflation tube attached to
the balloon, and the endoscopic housing shown in cross section.
FIG. 6 is a side view similar to FIG. 5, but shows the support rib and the
attached deflated balloon inserted into the endoscopic housing.
FIG. 7 shows a cross-section of the inflation and deflation tube inside the
endoscopic housing taken along the line 7--7 in FIG. 6.
FIG. 8 shows a side view of the second embodiment of the inflatable
retractor of the present invention after its exit from the endoscopic
housing, showing the support rib in an angled position, the inflated
balloon attached to the support rib, and the inflation and deflation tube
attached to the balloon.
FIG. 9 is a cross-section of the balloon and its attached support rib taken
along the line 9--9 in FIG. 8, showing the balloon inflated.
FIG. 10 is a schematic view of the second embodiment of the inflatable
retractor of the present invention, with the balloon inflated and
retracting the liver.
FIG. 11 is a top plan view of an embodiment of the inflatable balloon of
the present invention, showing its tapered shape.
FIG. 12 is a top plan view of a second embodiment of the inflatable balloon
of the present invention, showing its rectangular shape.
FIG. 13 is a side view of the balloon of FIG. 12, showing its curved tip.
FIG. 14 is a top plan view of a third embodiment of the inflatable balloon
of the present invention, showing its thin rectangular shape and rounded
tip.
FIG. 15 is a side view of an embodiment of the balloon of the present
invention, showing the support rib at a 180 degree angle, and the balloon
attached to the bottom of the support rib.
FIG. 16 is a side view of an embodiment of the balloon of the present
invention, showing the support rib at a 190 degree angle, and the balloon
attached to the bottom of the support rib.
FIG. 17 is a side view of an embodiment of the balloon of the present
invention, showing the support rib at a 225 degree angle, and the balloon
attached to the bottom of the support rib.
FIG. 18 is a side view of an embodiment of the balloon of the present
invention, showing the support rib at a 225 degree angle, and the balloon
attached to the top of support rib.
FIG. 19 is a side view of a third embodiment of the inflatable retractor of
the present invention, showing an endoscopic housing having 2 separate
chambers in cross section, and the retractor having a support rib with
attached balloon inserted in the first hollow chamber.
FIG. 20 is a side view of the third embodiment of the inflatable retractor
of the present invention similar to FIG. 19, but showing the support rib
with attached balloon exiting the housing.
FIG. 21 is a cross-sectional view of the endoscopic housing taken along
line 21--21 in FIG. 19, showing the 2 adjacent chambers and the inflation
and deflation tube.
FIG. 22 is a side view of the third embodiment of the inflatable retractor
of the present invention similar to FIG. 20, but showing the balloon
inflated.
FIG. 23 is a cross-sectional view taken along the line 23--23 in FIG. 22,
showing the inflated balloon and its attached support rib.
FIG. 24 is a side view of a fourth embodiment of the present invention
showing a single balloon having multiple projections, each projection
having its own angled support rib, an inflation and deflation tube
attached to the balloon, and the endoscopic housing shown in cross
section.
FIG. 25 is an end view of the multiple projections of the inflatable
balloon taken along the line 25--25 in FIG. 24.
FIG. 26 is a schematic view of the fourth embodiment of the present
invention, showing the multiple projections being used to retract the
liver and expose the gall bladder.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown a schematic view of a patient
undergoing an endoscopic cholecystectomy, illustrating only one example in
which the inflatable retractor 5 of the present invention might be
utilized during endoscopic surgery. A small endosurgical port A is shown,
through which an endoscope 10 is inserted. This allows the surgeon to view
the internal tissues and organs in the surgical area. Other surgical
devices (not shown) may be inserted through a similar surgical port C in
order to perform the desired procedure.
The retractor 5 of the present invention is inserted through a small
opening or port D made in the patient's body. A pair of endosurgical
forceps may be inserted through another surgical port B to aid in the
positioning of the endoscopic inflatable retractor 5.
As illustrated, the inflatable retractor is used to constrain and retract
the liver to permit the endosurgical removal of the gallbladder. It should
be noted, however, that the principles of the present invention are not
limited to any particular surgical procedure but may be applied to a wide
variety of procedures and applications, including open surgery.
Referring now to FIGS. 2-4, there is shown one embodiment of the endoscopic
inflatable retractor 5 of the present invention. FIG. 2 illustrates the
retractor 5 within a housing 15 suitable for use in endoscopic procedures.
The length of the housing 15 is primarily dependent upon the type of
procedure in which the retractor is to be used.
The housing 15 has a proximal or control end 20, and a distal or insertion
end 25. The housing 15 is preferably made of a material, such as stainless
steel, which will remain free from degradation, is easily sterilized, and
is biocompatible. The shape of the distal end 25 is chosen to aid in
preventing the puncture or other injury to internal organs and tissue when
the housing 15 is being manipulated inside the patient's body. The
proximal end 20 remains outside the patient's body during the procedure.
In addition to the cannula-like housing shown in FIGS. 2-4, the present
invention is also compatible with standard trocar-induced cannulas
frequently utilized in endoscopic surgery. Such cannulas provide a port
into the patient's body and a short tube for the insertion of endoscopic
instruments. Thus, the principles of the present invention are not to be
limited to any particular housing, cannula, or method of insertion into
the patient's body.
Still referring to FIG. 2, the inflatable retractor 5 consists of an long,
inflatable balloon 40 with an anatomical configuration designed to retract
structures specific to the surgical procedure. The balloon 40 is comprised
of a soft, flexible material which preferably does not absorb liquid and
is easily sterilized, such as rubber, vinyl, polyethylene, or other
polymeric material.
The balloon 40 of the inflatable retractor 5 is fabricated based upon MRI
or CT scan three-dimensional images of the area involved in the surgery.
An anatomical model of the internal structure to be retracted is
constructed based upon these three-dimensional images. This model is used
to construct a premolded, prevulcanized, or prefabricated
three-dimensional balloon 40 to conform to that anatomical model. In this
way, the retractors 5 can be fabricated to fit a variety of anatomical
configurations, and the surgeon can choose the retractor 5 which best fits
his needs during the endoscopic procedure.
Alternatively, the retractor 5 can be configured based upon MRI or CT scan
three-dimensional images of the anatomical structure of a particular
patient. An anatomical model of the internal structure of the patient is
constructed based upon the three-dimensional images. Using the model, the
three-dimensional balloon 40 is fabricated to conform to the internal
structures to be retracted. In this manner, a custom designed retractor
can be manufactured for use with a particular patient.
Referring again to FIG. 2, there is shown a small-diameter hollow tube 30
made of non-collapsible, flexible material which is connected to the
inflatable balloon 40 at the balloon's proximal end 41. This hollow tube
30 permits the entry and exit of gas or liquid to and from the inflatable
balloon 40. The proximal end of the tube 45 connects to an inflation and
venting device (not shown). This device can be any of a variety of
devices, including, for example, a bulb-type or piston-type syringe, a gas
cartridge, or a fluid pump.
Operation of the Retractor
The operation of the inflatable endoscopic retractor as used in a
cholecystectomy procedure will now be explained, as illustrated in FIGS. 3
and 4. The body is first prepared by introducing a state of
pneumoperitoneum to aid in the placement of the inflatable retractor 5.
The endoscopic housing 15 is inserted into an endosurgical port D in the
patient's body. An endoscope (not shown) may also be inserted into the
body to aid in visualizing the internal structures and to ensure the
proper positioning of the inflatable retractor 5. A pair of forceps 6
suitable for use in endoscopic surgery may be inserted into a different
endosurgical port B to aid in the positioning of the retractor 5.
As illustrated in FIG. 3, the balloon of the inflatable retractor 40 is
inserted into the proximal end of the endoscopic housing 20 and pushed
through using the inflation/deflation tube 30 until it emerges from the
distal end of the housing 25 into the patient's body. The balloon 40 may
be slightly inflated to aid in its maneuvering. As the balloon 40 emerges
from the distal end of the housing 25, it can be positioned by either
continuing to push the slightly inflated balloon 40 through the housing
25, or by inserting a pair of forceps 6 through a second endosurgical port
B in the patient's body. The forceps are used to grasp the distal end of
the inflatable balloon 41 and pull the balloon 40 through the endoscopic
housing 15 and into the desired position.
Referring now to FIG. 4, once the inflatable balloon 40 is in the desired
position, gas or liquid is introduced into the balloon 40 through the
hollow tube 30. As the balloon 40 inflates, it lifts and supports the
liver so as to expose the gallbladder. At this time, the retraction, as
necessary for procedures involving the gallbladder, will be sufficient,
and the condition of pneumoperitoneum may be allowed to lapse. If desired,
some insufflation may still be used along with the retractor of the
present invention to provide additional working space within the abdominal
cavity. The procedure involving the gallbladder may then be successfully
completed.
After the procedure has been completed, the balloon 40 is deflated by
allowing the gas or liquid to exit the balloon 40 through the hollow tube
30. The deflated balloon 40 is then removed from the body by pulling the
tube 30 away from the proximal end of the housing 20, thus drawing the
balloon 40 through the housing 15 and out of the patient's body. The
housing 15 itself may then be removed and the endosurgical port D sutured
closed.
Retractor With Support Rib
Referring now to FIGS. 5-9, there is shown an alternative preferred
embodiment of the retractor 49 of the present invention. The inflatable
balloon 50 is attached to a support rib 55, which is bent at an angle as
illustrated in FIG. 5. The balloon 50 and the support rib 55 may be joined
during the molding of the balloon 50, such that the balloon 50 is molded
around the support rib 55. The rib 55 may also be joined to the outside
surface of the balloon 50 using an adhesive. Others means of joining the
balloon 50 and support rib 55 will be readily apparent to one of ordinary
skill in the art.
The support rib 55 may have various configurations in order to provide
varying degrees of control and manipulation during retraction. For
example, in cross-section, the rib 55 may be circular, square, or
rectangular in shape. In addition, the rib may have various length and
width dimensions in order to vary the degree of rigidity of the retractor.
The rib 55 is preferably made of material such as spring steel, which is
flexible enough to allow the angled rib 55 to straighten upon insertion of
the rib 55 into an endoscopic housing 65 (FIG. 6) yet rigid enough to
spring back into its bent position and manipulate and support the desired
internal organ upon exit from the housing 65 (FIG. 8). The angle of the
rib 55 may be fixed, or it may be adjustable. This adjustability would at
the time of use, allow the surgeon to manually or mechanically adjust the
degree of the angle as well as the direction of the angle outside the
patient's body prior to insertion of the retractor, after viewing the area
to be retracted with an endoscope. This allows the surgeon to adjust the
retractor to fit his needs during the procedure.
The inflatable balloon 50 is attached to the support rib 55 and to a hollow
tube 70 used to inflate and deflate the balloon, as well as to push the
retractor 49 through the distal end of the housing 65 and position the
retractor 49 inside the patient's body. As shown in FIG. 7, the hollow
tube 70 fits within the endoscopic housing 65, and has a space 71 through
which gas or liquid passes during inflation or deflation of the balloon.
As shown in FIG. 8, the hollow tube 70 also assists in both supporting and
positioning the inflatable balloon 50 inside the body.
The operation of the inflatable retractor as used in a cholecystectomy will
now be explained with reference to FIG. 10. The endoscopic housing 65 is
inserted into an endosurgical port D in the patient's body. The balloon 50
and its attached support rib 55 are inserted into the proximal end of the
housing 66 and pushed through the distal end of the housing 67 and into
the desired position using the hollow tube 70 attached to the balloon 50.
Once the inflatable retractor 49 is in the desired position beneath the
liver, as shown in FIG. 10, air or other gas or liquid is introduced into
the balloon 50 through the hollow tub | | |
