Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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POSTMORTEM RECONSTITUTION OF CIRCULATION
BACKGROUND OF THE INVENTION
I. Field of the Invention
This invention relates to the reconstitution of vascular circulation in a
cadaver as a
mechanism for study of the vascular function, research and teaching of
surgical procedures
and general medical training. In addition, this invention aids in the
development and
evaluation of new medical devices using techniques for reconstituting the
vascular flow of a
fluid simulating blood in a fresh (as opposed to an embalmed) cadaver.
2. Description of the Related Art
Training physicians and other medical care personnel and surgical associates
for
performing specific surgeries requires an appropriate model system. It is
highly desirable for
medical trainees to be able to practice and hone their skills on a model
system, rather than on
a live person in need of a particular treatment. Similarly, both the
development of and new
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medical devices benefit from testing on a model system. Verification of
physical and operating
parameters of the device, development of surgical procedures for implantation
of the device
and training of medical care personnel to learn how to place and use these
devices in a body
are materially improved if there is a close model of the in vivo human system
available for
these activities. Indeed, there is the potential for a great deal of harm to a
patient if the
physician has not had the appropriate training or a particular device has not
been
appropriately evaluated and its performance characteristics verified. This is
especially true
for physicians and devices related to the endovascular system.
As the field of endovascular intervention steadily increases, there is an
increasing need
to train physicians and other surgical associates to perform new surgical
techniques and to use
new interventive devices. The new surgical techniques and new devices require
training and
practice on the part of the physicians and other surgical associates. In fact,
the process of
development of such new devices themselves is enhanced and facilitated with
the ability to
place prototypes into an "in vivo" environment, first to refine the physical
parameters of the
device and then to predict efficacy and utility before they are used on a live
patient. All of
these needs require an appropriate model system for replicating the
implantation and device
function prior to the implantation in a human.
To date, the only models available for this purpose involve either plastic
models
perfused with water and built to imitate the human vascular tree, or live
animal models. For
example, U.S. Patent No. 5,632,623 discloses a mock circulation system having
a plurality
of channels formed within a housing to represent the arteries, veins and
organs of a human
circulatory system. The 5,632,623 system uses an artificial ventricle such as
the type which
are implanted in experimental animals including humans. Unfortunately, plastic
models like
the 5,632,623 model, do not have the same feel as human tissues or the same
strength. Thus,
testing devices on plastic model systems often does not recreate the
situations found in human
beings.
Animal models also have significant disadvantages. A major disadvantage is
that the
animals often differ significantly from humans in terms of their vascular
anatomy as well as
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in the size of their vessels. Thus, training and testing on animal systems
does not closely
simulate the situations a medical associate or a medical device would
encounter in a human
body.
Life-like human models are more appropriate than plastic or animal models for
practice and training purposes and could also accelerate the testing of new
devices. While
various systems using fresh human cadavers have been described previously,
these systems
are designed to embalm a body, not to reestablish circulation in isolated and
discrete circuits
of the body. For example, U.S. Patent No. 2,369,694, U.S. Patent No.
2,388,337, U.S.
Patent No. 2,401,849 and U.S. Patent No. 2,462,617 all describe methods and
pumps for
preparing a cadaver for a burial which includes forcing the liquid embalming
fluid into a body.
They do not establish any type of circulation throughout the body, and in
particular they do
not isolate or re-establish any specific circulatory circuit.
Other systems for use on human organs are designed to preserve the human
organs
for eventual transplantation. For example, U.S. Patent No. 5,066,578 describes
the perfusion
of human organs such as liver, kidney, pancreas, spleen, brain, embryo,
testicles, ovaries, lung
or heart-lung complex with a specific physiological preservation solution.
Unlike the instant
invention, this method involves the practice of isolating and perfusing organs
separate and
away from the natural circulatory environment of the human body. Such approach
specifically
does not use the human body's own circulatory circuits for reconstituting or
emulating
circulation. U.S. Patent No. 4,666,425 (reexamination certificate issued Feb
25, 1992 in
which all 20 claims were canceled) describes the use of a device to supply a
discorped head
with oxygenated blood and nutrients. Similar to the 5,066,578 patent, the
methods described
in the 4,666,425 patent distinctly do not use the human body's own circulatory
circuits to
maintain the circulation.
SUMMARY OF THE INVENTION
The inventive method provides a model system which can be used to isolate
specific
naturally occurring vascular circuits for both teaching and device development
and evaluation
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purposes. The method has been designed to overcome the prior art problems of
the plastic
and non-human animal models by reconstituting circulation in the major vessels
of a fresh,
non-embalmed, non-heart-beating human cadaver.
Fresh, frozen cadavers are readily available for scientific investigation. By
reconstituting, or simulating, the normal circulation patterns on these fresh
cadavers, medical
care personnel can develop, evaluate and practice specific endovascular
procedures, as well
as facilitate development and evaluation of various endovascular devices.
Using actual human
bodies offers the significant advantage of allowing the practitioner/trainee
to operate on a
model having the actual size and placement of the human vessels, as well as
provide the
realism that a plastic model necessarily lacks. Since actual human anatomy is
used, this system
provides a life-like training and testing situation.
The system of the instant invention provides at least a three-fold benefit: 1)
a superior
model system for research and development of new infra-operative techniques,
2) acceleration
of the development of medical devices, particularly those which meet the
United States Food
and Drug Administration (FDA) guidelines, and 3) a powerful teaching tool so
as to
accelerate the learning curve of physicians and other surgical associates.
Additionally, the
inventive system further advances the knowledge, understanding and techniques
associated
with reconstituting circulation in a cadaver. This can lead to new
methodologies in device
research, including vascular stents, aortic devices, catheter and other
vascular based
interventional studies.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic view of the right carotid circuit of the human
vascular system;
Figure 2 is a schematic view of a the carotid circuit and the aorta circuit of
the human
vascular system illustrating two embodiments of the inventive system;
Figure 3 is a schematic views of an abdominal aorta circuit according to the
inventive
system; and
Figure 4 is a schematic view of a leg circuit according to the inventive
system.
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DETAILED DESCRIPTION OF INVENTION
The methodology of this invention involves the use of a whole fresh human
cadaver.
The cadaver is preferably fresh, frozen, non-heart beating and non-embalmed.
The method
of re-establishing or reconstituting vascular circulation in the cadaver shows
great promise
for medical teaching, surgeon training (both in surgical technique as well as
device placement)
and in device development and evaluation. Particularly, because the tissue of
the fresh
cadaver involved simulates that of the live human, training surgeons in the
placement of such
as catheters, stents and stented grafts is particularly effective.
In the procedure of the instant invention, generally the cadaver will have the
thrombi
removed from the major vessels through the use of a purging solution, such as
Permico
solution available from the Dodge Co. In conjunction with cleaning out
thrombi, it is
preferable to add known agents which prolong the natural characteristics of
the tissue of the
cadaver to as closely to those when the cadaver was alive. The closer that the
vascular tissue
integrity and elasticity can be held to its original character, the better
will the reconstituted
system provide "in vivo" approximation. Thus, it is useful to add stabilizers
which preserve
vessel integrity including such as glycerol and aloe extract. Further, gentle
preservatives such
as dilute formulations of alcohol are advantageous. Finally, the addition of
dilute amounts
of one or more of antimicrobial drugs will further preserve the useful life of
the model. An
incision is made in as many arteries as necessary, and a chemical compound
used for
dissolving clots in cadaver arteries is infused into the arterial tree.
Usually, several arterial
sites are accessed by direct incision and the arteries are exposed surgically.
Which particular
arteries to be exposed will depend on which circuit is to be isolated and
reestablished. For
example, when isolating the aortic circuit, both carotid arteries and both
femoral arteries are
exposed. When isolating the head and neck or upper extremity circuit, both of
the axillary
arteries are exposed. Once the arterial tree has been adequately cleared of
all thrombi, it is
prepared for use depending on which portion of the arterial tree is scheduled
for investigation.
In this respect "adequately cleaned" means the cleaning out of inclusions such
as blood clots
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so as to enable a fluid flow in the selected circuit which emulates a
reconstituted circulation
of human blood in the circuit.
In the establishment of a circuit to be studied, endovascular occlusion points
are
established at the limits of the circuit to be studied. This is accomplished
by one of a variety
of means. One preferred embodiment is by means of a balloon catheter, which,
when inflated,
occludes the vein or artery but allows access by the surgeon through a
selectively openable
lumen of the catheter. It is our preference to utilize a large bore occluding
balloon catheter,
such as the Meditek OB (non-tapered) catheter available from Boston Scientific
Company.
For example, when reconstituting circulation through the abdominal aortic
circuit, access is
established by placing the balloon catheter into the descending thoracic aorta
(see, Figure 3).
Points of egress are established by selectively occluding appropriate vessels.
For example,
in the abdominal aortic circuit, incisions in the left and right carotid
arteries used for flushing
are subsequently occluded, while the incisions in the left and right femoral
arteries are left
open. The incisions in the left and right femoral arteries in this case can be
cannulated for
convenience to allow better control of the fluid emerging from these vessels.
The cadaver is preferably manually infused with a perfusate, or preferably
hooked to
pump for the purpose of reconstituting circulation within the major vessels.
Generally, the
rotary head pump of a heart-lung perfusion machine is used. However, any pump
capable of
establishing circulation through various bodily access and egress points can
be used. For
example, when isolating the abdominal aortic circuit, the pump is connected to
a point of
access through the descending thoracic aorta, and to points of egress through
the femoral
vessels.
The abdominal aortic circuit is not the only circuit that can be isolated and
utilized
for the study of devices or procedures using the inventive reconstitution of
circulation system.
Examples of other circuits that can be studied using this system include, but
are not limited
to, the circulation within the major vessels of the intercostal cavity, the
coronary vessels, the
carotid vessels (see Figure 2), the central thoracic system (see, Figure 3),
and an extremity
such as an arm, or a leg (see, Figure 4). Particular legs of each of these
circuits can be
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individually selected using the method of the present invention. Particularly,
the axial,
brachial, iliac, femoral, popiteal and pulminary arteries, the vertebral,
basilar, renal and
mesenteric vessels are already of interest. Others may be isolated and
investigated as dictated
by devices or procedures of interest.
In the case of the left carotid circuit, left and right femoral arteries are
occluded in the
iliac region (see Figure 2). One of the arteries is selected for the ingress
of fluid from the
heart-lung machine and the other is selected as the ingress for the surgical
access. Depending
upon the extent of the circuit to be examined, the upper occlusion may be at
one or more of
several sites. Frequently, occlusion and access or egress points are selected
in the right and
left subclavian arteries adjacent the upper aorta. As can be seen in Figure 2,
a balloon
catheter is placed near the juncture of the right subclavian artery and the
right common
carotid artery. Through the circuit flow of the heart-lung machine, the left
carotid circuit is
isolated. Upward flow is permitted in the carotid arteries allowing
investigation of the small
distal circuits of the brain.
While discussion is focused upon the isolation of certain arterial circuits
for
investigation or surgical intervention, the invention is useful in
corresponding venous circuits.
Similar procedures for access, egress and occlusion are followed, tailored to
the circuit
chosen.
Figure 4 illustrates the occlusion, flow entry and egress and surgical access
points for
a leg circuit. Here, circulation is established via entry through the
superficial femoral artery
and egress through the posterior tibial artery and dorsalis pedus artery. This
allows isolation
and study of the leg circuitry.
There are several objectives in isolating the circuits. One is to optimize
flow to
emulate the in vivo performance. In the in vivo flow of blood in the live
system, blood flow
is in relatively high volume, and well contained within the particular systems
(i.e., doesn't
normally "leak" into extraneous cavities). It is difficult to achieve this in
the post mortem
situation because if a limited capacity to circulate the blood substitute and
such as the
capillary beds are absorptive of the blood and not able to return it through
the venous system.
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Through the use of occluding devices such as the balloon catheters, the flow
of fluid into
unwanted circuits, cavities and capillaries may be controlled, thereby
preserving the generated
fluid flow to those circuits within the cadaver which are of immediate
interest..
By reconstituting circulation through these different circuits, various
medical devices
and/or procedures utilizing such devices may be studied, developed, evaluated
and tested.
Performance of prototypes of devices being developed may be studied for the
utility and
efficacy of the device. Concurrently, the surgical procedure by which the
device is implanted
or utilized may be developed, and evaluated. The range of devices and
procedures is
extensive and will grow as the awareness of the invention and the extent of
its utility.
Currently, there is application for non-implantable and diagnostic devices
such as guiding
catheters, guide wires, therapeutic devices including those for temporary
occlusion or
reestablishment of circulation. Further, the ability to evaluate implantable
stents, graphs,
stent-graphs, occlusive materials including coils and cements and acrylics and
to develop and
train surgeons on the use of such devices in a setting very similar to that
faced in vivo will
enhance the professional development of surgeons and their teams.
During procedures performed on the cadaver, fluoroscopy can be used to
visualize
the flow through the specific circuit isolated. Likewise, ultrasound may be
utilized to evaluate
flow parameters and patterns of the chosen fluid. Such observation tools as
fluoroscopy and
ultrasound allows continual monitoring of the positioning of the surgical
instrumentation, a
device and the fluid flow as it is moved through the vascular system. A dye or
other visual
enhancer may be added to the fluid to aid in this visualization. In the case
of a dye is
conveniently red to simulate blood. Alternatives to the described fluid are
heterogolus blood
which imparts certain of the properties of blood, and fluids including micro
particles or
reflectors for sensing by ultrasound. A particular use of such a particle
containing fluid is in
the training, research and development of ultrasound equipment. Similar use
may be made
for other tracking instrumentation including angiography, angioscopy,
computerized
tomography and scintography, and magnetic resonance.
In some surgeries, a heater or a cooler or both may be included to simulate
normal or
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various other body temperatures, or to enhance the performance of the fluid
chosen for
circulation.
Example 1: Reconstitution of Abdominal Aorta Circulation
The lower thoracic, abdominal aorta and iliac arteries can be isolated for
study. For
work on this portion of the arterial tree and its major branches, which
include the mesenteric
and renal vessels, an arterial to arterial circulation is created (see Figures
2 and 3).
In order to begin to recreate circulation in these areas, the right 14 and
left femoral
16 arteries are dissected and exposed. First, incisions 15 and 17 are made
into the cadaver,
indicated generally by the letter C, at the approximate location of the
femoral arteries 14 and
16. These incisions 15 and 17 are then separated so that the physician or
other worker can
dissect down to the artery itself. These incisions 15 and 17 are made to
ensure that there will
be enough room to work on and around the femoral arteries 14 and 16 even after
the
placement of a cannula within the arteries 14 and 16. To keep excess fluid
from leaking out
of the system, the femoral arteries 14 and 16 can be tied off as they are
being exposed and
dissected.
In addition to exposing both the right 14 and left 16 femoral arteries, the
right 10 and
left 12 carotid arteries are also exposed in a similar manner. The appropriate
incisions in the
neck 11 and 13 are made by utilizing the standard anatomical landmarks, here
at the location
of the right 10 and left 12 carotid arteries. Only a small portion of the
carotid arteries 10 and
12 need be dissected out as they are used, in this example, for flushing
purposes only.
The purpose of the flushing process is to remove the thrombi and excess blood
from
the system, in order to reconstitute the function of the selected circuit,
here the abdominal
aorta. In this example, an MKI Portaboy (not shown) was used. However, any
device
capable of pumping fluid into a system such as this can be used. The Portaboy
is normally
used for embalming. However, by replacing the embalming fluid with the
described solution,
the pump may be used to flush out the circuits of remaining fluid (including
blood). In this
example, a solution comprising 2 gallons of sterile water and 32 oz. of
Permaco was used, but
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those skilled in the art recognize that alternatives may be used so long as it
does not degrade
the body tissue and materially affect its "live" character.
Incisions 11 and 13 are made in both the right 10 and left 12 carotid arteries
and in
both the right 14 and left 16 femoral arteries. These incisions I1 and 13 are
made at
approximately the same positions on opposite sides. The incisions are selected
as a function
of the examination; i.e., the device or modality to be examined. The benefit
to be gained from
the invention is to examine the surgical device or conduct the diagnosis or
surgery in an
environment simulating as closely as possible that in a live human. Therefore,
the access to
the selected circuit is set to provide the same theater, both as to location
and the simulation
of the hematological environment. It is to be remembered that the present
invention may be
used not only in the surgical context, but also in the hematological context,
as by investigating
such as the clotting effect of a device and the device's effect on blood flow.
Thus, it is
important to make sure that the incision within the arteries (or other
vessels) are located such
that there is still plenty of room to work on the vessel after, for example, a
cannula (not
shown) is in place.
Flushing is begun by placing the outflow tube of the Portaboy within the
incision in
one of the vessels and turning on the Portaboy. Fluid from the Portaboy is set
to flow at
pressure from about 20 to about 50 cm of water. It is unusual to use pressures
higher than
50 cm on a Portaboy due to concern with causing damage to the circuit being
flushed. Fluid
passes from the Portaboy through the several circuits to the egress and is
collected. It is usual
to flush out all of the large arteries and veins. In this example, an outflow
tube (not shown)
is placed within the right carotid artery 10 first, allowing fluid to flow
from the right carotid
artery 10 and out through the incision 13 in the left carotid artery 12 as
well as the incisions
15 and 17 of the right 14 and left 16 femoral arteries. Fluid flow is
indicated generally by the
arrows in the Figures. The fluid that is expelled from these vessels is
suctioned off so that
clots and fluid around the vessels does not pool and inhibit later
examinations. The outflow
tube from the Portaboy may also be placed within one of several of the other
dissected vessels
such as the incision 13 in the left carotid artery 12, the incision 15 in the
right femoral artery
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14 and the incision 17 in the left femoral artery 16 to ensure that all of the
vessels are cleared
of clots and excess blood.
In order to ensure that all of the flushing fluid and thrombi are cleaned out
through
specific vessels, one or more of the dissected vessels can be selectively
occluded. For
example, by placing the outflow tube from the Portaboy in the incision 15 in
the right femoral
artery 14 and occluding the left femoral artery 16, all of the flushing fluid
from the Portaboy
is forced out through the incisions 11 and 13 in the right 10 and left 12
carotid arteries.
Similarly, by placing the outflow tube from the Portaboy into the incision 11
of the right
carotid artery 10 and occluding the left carotid artery 12, flushing fluid is
forced out through
the incisions 15 and 17 of the right 14 and left 16 femoral arteries.
Flushing of the vessels continues until the fluid that is passing out through
the vessels
is clear. Clear fluid indicates that all of the clots and excess blood from
the system have been
removed. This is normally accomplished by one continuous flush.
At this point, an arteriogram can be done to ensure that the vessels are
completely
cleared out. Hypaque, a diatrizoate solution, or any other radiopaque medium
can be
perfused into the vessels to allow visualization during the radiography. By
visually following
the radiopaque medium through the vessels, the clearance of the vessels can be
determined.
After the system is flushed out in this manner, the incisions 11 and 13 of the
carotid
arteries 10 and 12 are occluded, and the sternum (S) is opened up in order to
cannulate the
descending thoracic aorta 20. This is done in a manner similar to the
dissection and
cannulation of the carotid 10 and 12 and femoral 14 and 16 arteries. An
incision 19 is made
at the chest, spread open, and dissected down to the aorta 18. With the
descending thoracic
aorta 20 cannulated, the right 14 and left 16 femoral arteries cannulated, and
the right 10 and
left 12 carotid arteries occluded, the abdominal aorta 23 circulation is
isolated.
A large bore balloon tipped catheter 50 such as the Meditek OB catheter
available
from Boston Scientific Co., mentioned previously, is positioned an incision 21
in the
descending thoracic aorta 20 and the balloon 50 is expanded to occlude the
artery 20 at this
level. Any fluid may then be infused through this large bore catheter 50. Two
outflow
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catheters (not shown) are placed in incisions 15 and 17 of the femoral
arteries 14 and 16 and
the circulation is established with inflow through the incision 21 in the
thoracic aorta 20 and
outflow through the incisions 15 and 17 in the femoral arteries 14 and 16
simulating normal
human circulation. This allows work on the descending thoracic aorta 20,
abdominal aorta
23, right 60 and left 62 iliac arteries, the common femorals and all their
branches including
the renal and visceral vessels (not shown).
As mentioned previously, variety of solutions may be used for the
reconstitution of
circulation, depending upon the particular examination to be performed, such
as the device
or the flow of the fluid. However, commonly used solutions include, but are
not limited to
ringer's lactate, Hespan, and saline. Likewise, traditional volume replicate
solutions,
radiographic, sonographic, centagaphic contrast media may be employed, as well
as
crystalloids and colloids to enhance the observation of properties to be
examined. One reason
for the use of ringer's lactate is that it is inexpensive. In addition, red
dye can be added to
simulate the appearance of blood.
While the same pump used for flushing the vessels, a separate pump might be
employed if desired to reconstitute the circulation of fluid in the selected
circuit. The pump
will be operated intermittently or continuously depending upon the procedure
and properties
to be examined. For example, during fluoroscopy the pump will operate
continuously so that
flow can be visualized. In such example, a standard rotary head pump normally
used during
cardiopulmonary bypass for heart surgery is used. However, any pump that will
achieve the
same result can be used. The pump used in this example has a reservoir so that
additional
fluid or markers such as micro bubbles or reflectors may be added. A heater, a
cooler, or
both may be included in the circuit to simulate normal or other body
temperature. This
system allows adequate perfusion of the lower thoracic, and abdominal aorta
and iliac arteries
and its major branches for instrumentation and placement of such as
angioplasty catheters,
stents, and stented grafts.
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Example 2: Reconstitution of Carotid Artery Circulation
For reconstruction of blood circulation of the carotid arteries and intra
cerebral
vasculature, an alternative embodiment of the invention may be used as
illustrated in Figures
2 and 3. In this embodiment, axillary arteries 64 and 66 and one carotid
artery (10 or 12) are
dissected and exposed. These vessels are then flushed out similarly to the
procedure
described in Example 1.
A large bore balloon tipped catheter 50 may then be placed in the incision 21
made
in the descending thoracic aorta 20 , as in Example 1 however, in this
embodiment, it is
directed toward the head, indicated generally as H. An outflow catheter (not
shown) is
placed in the incisions 65 and 67 made in both axillary arteries 64 and 66 and
in the incision
11 or 13 of one carotid artery 10 or 12. Inflow of the selected perfusate,
with such
inclusions, markers and the like, is then established through the incision 21
of the thoracic
aorta 20 with outflow, indicated generally by the arrows, through the
incisions 65 and 67
made in axillary arteries 64 and 66 and the incision 11 or 13 of one carotid
artery 10 or 12.
Again, similar to Example 1, this generates a reconstruction of circulation in
this circuit
simulating normal blood flow in the human. Catheters (not shown) may be passed
through
the incisions 11 or 13 of the carotid arteries 10 or 12 or the incisions 65
and 67 in the axillary
arteries 64 or 66 for instrumentation of the extra cranial and intra cranial
vasculature for
similar purposes of testing and training. Upward flow in a carotid artery
permits antegrade
net flow in the small, distal vessels of the brain. Cranial flow is less
structured than such as
the intercostal cavity in that flow is supplied to the brain through chosen
arteries and allowed
to flow generally through the brain. Thus, there is no formal point of egress
for the fluid.
Example 3: Reconstitution of Leg or Arm Circulation
An alternative method of the instant invention may be used in reconstruction
of
circulation in an arm or a leg (see, Figure 4). For example, by establishing
inflow through the
femoral artery 14 and outflow through the distal tibial vessels 32, 34 and 36,
the inventive
reconstructed circulation system creates a model to allow instrumentation of
the lower
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extremity vessels for the development and evaluation of devices, diagnostic or
surgical
techniques.
To reconstitute circulation in the right leg, for example, the posterior
tibial artery 36
and dorsalis pedus artery 38 are exposed, dissected, and flushed out in a
manner similar to
exposure and flushing of the femoral 14 and 16 or carotid 10 and 12 arteries.
Once these
arteries are cleared of clots and excess fluid, reconstruction of circulation
through the right
leg R and its associated vessels may be initiated. In the practice of the
invention, inflow of
the selected perfusate is established through an incision 69 in the
superficial femoral artery
68 and outflow through incisions 37 and 39 in the posterior tibial artery 36
and the dorsalis
pedus artery 38, respectively. As with the other embodiments described above,
the natural
opacity of the vessels obscures flow of the fluid in the arteries in the leg
necessitating the use
of such as fluoroscopy or ultrasound for visualization of each of the vessels
and their
associated branches and movement of devices and instruments during
examination.
Similarly, inflow can be established through the axillary artery 64 or 66 with
outflow
through the radial and ulnar arteries (not shown) to allow instrumentation of
the upper
extremity vessels.
The following table lists the body elements and descriptions as used herein
and
in the drawings attached hereto:
ELEMENTS LIST
Number Description
C Cadaver
S Sternum
10 right carotid artery
11 Incision in the right carotid artery
12 Left carotid artery
13 Incision in the left carotid artery
14 Right femoral artery
15 Incision in the right femoral artery
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16 Left femoral artery
17 Incision in the left femoral artery
18 Aorta
19 Incision in the sternum/chest
20 Descending thoracic aorta
21 Incision in the descending thoracic aorta
22 Occlusion points
23 Abdominal aorta
30 Gut
32 Anterior tibial artery
34 Peroneal artery
36 Posterior tibial artery
37 Incision in the posterior tibial artery
38 Pedus dorsalis
39 Incision in the pedus dorsalis
40 Visceral branches
50 Balloon catheter
52 Anterior communicating artery
54 Posterior communicating artery
56 Right subclavian artery
58 Left subclavian artery
60 Right iliac artery
62 Left iliac artery
64 Right axillary artery
65 Incision in the right axillary artery
66 Left axillary artery
67 Incision in the left axillary artery
68 Superficial femoral artery
5001311 -15- MERI/Reconst.pat
CA 02299964 2000-03-06
The foregoing disclosure and description of the invention are illustrative and
explanatory
thereof, and various changes in the details of the illustrated apparatus and
construction and
method of operation may be made without departing from the spirit of the
invention.
50013/1 -16- MERI/Reconstpat
